Add Nokia CBUS support

Add Nokia CBUS support
Signed-off-by: Juha Yrjola <juha.yrjola@solidboot.com>

arch/arm/Kconfig

@@ -1037,6 +1037,10 @@ source "drivers/mmc/Kconfig"
 
 source "drivers/rtc/Kconfig"
 
+if ARCH_OMAP
+source "drivers/cbus/Kconfig"
+endif
+
 endmenu
 
 source "fs/Kconfig"

drivers/Makefile

@@ -27,7 +27,7 @@ obj-$(CONFIG_FB_INTEL)          += video/intelfb/
 
 obj-y				+= serial/
 obj-$(CONFIG_PARPORT)		+= parport/
-obj-y				+= base/ block/ misc/ mfd/ net/ media/
+obj-y				+= base/ block/ misc/ mfd/ net/ media/ cbus/
 obj-$(CONFIG_NUBUS)		+= nubus/
 obj-$(CONFIG_ATM)		+= atm/
 obj-y				+= macintosh/

drivers/cbus/Kconfig

+#
+# CBUS device configuration
+#
+
+menu "CBUS support"
+
+config CBUS
+	depends on ARCH_OMAP
+	bool "CBUS support on OMAP"
+	---help---
+	  CBUS is a proprietary serial protocol by Nokia.  It is mainly
+	  used for accessing Energy Management auxiliary chips.
+
+	  If you want CBUS support, you should say Y here.
+
+config CBUS_TAHVO
+	depends on CBUS
+	bool "Support for Tahvo"
+	---help---
+	  Tahvo is a mixed signal ASIC with some system features
+
+	  If you want Tahvo support, you should say Y here.
+
+config CBUS_TAHVO_USER
+	depends on CBUS_TAHVO
+	bool "Support for Tahvo user space functions"
+	---help---
+	  If you want support for Tahvo's user space read/write etc. functions,
+	  you should say Y here.
+
+config CBUS_TAHVO_USB
+	depends on CBUS_TAHVO && USB
+	tristate "Support for Tahvo USB transceiver"
+	---help---
+	  If you want Tahvo support for USB transceiver, say Y or M here.
+
+config CBUS_TAHVO_USB_HOST_BY_DEFAULT
+	depends on CBUS_TAHVO_USB && USB_OTG
+	boolean "Device in USB host mode by default"
+	---help---
+	  Say Y here, if you want the device to enter USB host mode
+	  by default on bootup.
+
+config CBUS_RETU
+	depends on CBUS
+	bool "Support for Retu"
+	---help---
+	  Retu is a mixed signal ASIC with some system features
+
+	  If you want Retu support, you should say Y here.
+
+config CBUS_RETU_USER
+	depends on CBUS_RETU
+	bool "Support for Retu user space functions"
+	---help---
+	  If you want support for Retu's user space read/write etc. functions,
+	  you should say Y here.
+
+config CBUS_RETU_POWERBUTTON
+	depends on CBUS_RETU
+	bool "Support for Retu power button"
+	---help---
+	  The power button on Nokia 770 is connected to the Retu ASIC.
+
+	  If you want support for the Retu power button, you should say Y here.
+
+config CBUS_RETU_RTC
+	depends on CBUS_RETU && SYSFS
+	tristate "Support for Retu pseudo-RTC"
+	---help---
+	  Say Y here if you want support for the device that alleges to be an
+	  RTC in Retu. This will expose a sysfs interface for it.
+
+config CBUS_RETU_WDT
+	depends on CBUS_RETU && SYSFS
+	tristate "Support for Retu watchdog timer"
+	---help---
+	  Say Y here if you want support for the watchdog in Retu. This will
+	  expose a sysfs interface to grok it.
+
+config CBUS_RETU_HEADSET
+	depends on CBUS_RETU && SYSFS
+	tristate "Support for headset detection with Retu/Vilma"
+	---help---
+	  Say Y here if you want support detecting a headset that's connected
+	  to Retu/Vilma. Detection state and events are exposed through
+	  sysfs.
+
+endmenu

drivers/cbus/Makefile

+#
+# Makefile for CBUS.
+#
+
+obj-$(CONFIG_CBUS)		+= cbus.o
+obj-$(CONFIG_CBUS_TAHVO)	+= tahvo.o
+obj-$(CONFIG_CBUS_RETU)		+= retu.o
+obj-$(CONFIG_CBUS_TAHVO_USB)	+= tahvo-usb.o
+obj-$(CONFIG_CBUS_RETU_POWERBUTTON) += retu-pwrbutton.o
+obj-$(CONFIG_CBUS_RETU_RTC)	+= retu-rtc.o
+obj-$(CONFIG_CBUS_RETU_WDT)	+= retu-wdt.o
+obj-$(CONFIG_CBUS_TAHVO_USER)	+= tahvo-user.o
+obj-$(CONFIG_CBUS_RETU_USER)	+= retu-user.o
+obj-$(CONFIG_CBUS_RETU_HEADSET)	+= retu-headset.o

drivers/cbus/cbus.c

+/*
+ * drivers/cbus/cbus.c
+ *
+ * Support functions for CBUS serial protocol
+ *
+ * Copyright (C) 2004, 2005 Nokia Corporation
+ *
+ * Written by Juha Yrjl <juha.yrjola@nokia.com>,
+ *	      David Weinehall <david.weinehall@nokia.com>, and
+ *	      Mikko Ylinen <mikko.k.ylinen@nokia.com>
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file "COPYING" in the main directory of this
+ * archive for more details.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/spinlock.h>
+
+#include <asm/arch/gpio.h>
+#include <asm/arch/board.h>
+
+#include <asm/io.h>
+
+#include "cbus.h"
+
+struct cbus_host *cbus_host = NULL;
+
+#ifdef CONFIG_ARCH_OMAP1
+/* We use our own MPUIO functions to get closer to 1MHz bus speed */
+
+static inline void cbus_set_gpio_direction(u32 base, int mpuio, int is_input)
+{
+	u16 w;
+
+	mpuio &= 0x0f;
+	w = __raw_readw(base + OMAP_MPUIO_IO_CNTL);
+	if (is_input)
+		w |= 1 << mpuio;
+	else
+		w &= ~(1 << mpuio);
+	__raw_writew(w, base + OMAP_MPUIO_IO_CNTL);
+
+}
+
+static inline void cbus_set_gpio_dataout(u32 base, int mpuio, int enable)
+{
+	u16 w;
+
+	mpuio &= 0x0f;
+	w = __raw_readw(base + OMAP_MPUIO_OUTPUT);
+	if (enable)
+		w |= 1 << mpuio;
+	else
+		w &= ~(1 << mpuio);
+	__raw_writew(w, base + OMAP_MPUIO_OUTPUT);
+}
+
+static inline int cbus_get_gpio_datain(u32 base, int mpuio)
+{
+	mpuio &= 0x0f;
+
+	return (__raw_readw(base + OMAP_MPUIO_INPUT_LATCH) & (1 << mpuio)) != 0;
+}
+
+static void cbus_send_bit(struct cbus_host *host, u32 base, int bit,
+			  int set_to_input)
+{
+	cbus_set_gpio_dataout(base, host->dat_gpio, bit ? 1 : 0);
+	cbus_set_gpio_dataout(base, host->clk_gpio, 1);
+
+	/* The data bit is read on the rising edge of CLK */
+	if (set_to_input)
+		cbus_set_gpio_direction(base, host->dat_gpio, 1);
+
+	cbus_set_gpio_dataout(base, host->clk_gpio, 0);
+}
+
+static u8 cbus_receive_bit(struct cbus_host *host, u32 base)
+{
+	u8 ret;
+
+	cbus_set_gpio_dataout(base, host->clk_gpio, 1);
+	ret = cbus_get_gpio_datain(base, host->dat_gpio);
+	cbus_set_gpio_dataout(base, host->clk_gpio, 0);
+
+	return ret;
+}
+
+#else
+
+#define cbus_set_gpio_direction(base, gpio, is_input) omap_set_gpio_direction(gpio, is_input)
+#define cbus_set_gpio_dataout(base, gpio, enable) omap_set_gpio_dataout(gpio, enable)
+#define cbus_get_gpio_datain(base, int, gpio) omap_get_gpio_datain(gpio)
+
+static void _cbus_send_bit(struct cbus_host *host, int bit, int set_to_input)
+{
+	omap_set_gpio_dataout(host->dat_gpio, bit ? 1 : 0);
+	omap_set_gpio_dataout(host->clk_gpio, 1);
+
+	/* The data bit is read on the rising edge of CLK */
+	if (set_to_input)
+		omap_set_gpio_direction(host->dat_gpio, 1);
+
+	omap_set_gpio_dataout(host->clk_gpio, 0);
+}
+
+static u8 _cbus_receive_bit(struct cbus_host *host)
+{
+	u8 ret;
+
+	omap_set_gpio_dataout(host->clk_gpio, 1);
+	ret = omap_get_gpio_datain(host->dat_gpio);
+	omap_set_gpio_dataout(host->clk_gpio, 0);
+
+	return ret;
+}
+
+#define cbus_send_bit(host, base, bit, set_to_input) _cbus_send_bit(host, bit, set_to_input)
+#define cbus_receive_bit(host, base) _cbus_receive_bit(host)
+
+#endif
+
+static int cbus_transfer(struct cbus_host *host, int dev, int reg, int data)
+{
+	int i;
+	int is_read = 0;
+	unsigned long flags;
+	u32 base;
+
+#ifdef CONFIG_ARCH_OMAP1
+	base = (u32) io_p2v(OMAP_MPUIO_BASE);
+#else
+	base = 0;
+#endif
+
+	if (data < 0)
+		is_read = 1;
+
+	/* We don't want interrupts disturbing our transfer */
+	spin_lock_irqsave(&host->lock, flags);
+
+	/* Reset state and start of transfer, SEL stays down during transfer */
+	cbus_set_gpio_dataout(base, host->sel_gpio, 0);
+
+	/* Set the DAT pin to output */
+	cbus_set_gpio_direction(base, host->dat_gpio, 0);
+
+	/* Send the device address */
+	for (i = 3; i > 0; i--)
+		cbus_send_bit(host, base, dev & (1 << (i - 1)), 0);
+
+	/* Send the rw flag */
+	cbus_send_bit(host, base, is_read, 0);
+
+	/* Send the register address */
+	for (i = 5; i > 0; i--) {
+		int set_to_input = 0;
+
+		if (is_read && i == 1)
+			set_to_input = 1;
+
+		cbus_send_bit(host, base, reg & (1 << (i - 1)), set_to_input);
+	}
+
+	if (!is_read) {
+		for (i = 16; i > 0; i--)
+			cbus_send_bit(host, base, data & (1 << (i - 1)), 0);
+	} else {
+		cbus_set_gpio_dataout(base, host->clk_gpio, 1);
+		data = 0;
+
+		for (i = 16; i > 0; i--) {
+			u8 bit = cbus_receive_bit(host, base);
+
+			if (bit)
+				data |= 1 << (i - 1);
+		}
+	}
+
+	/* Indicate end of transfer, SEL goes up until next transfer */
+	cbus_set_gpio_dataout(base, host->sel_gpio, 1);
+	cbus_set_gpio_dataout(base, host->clk_gpio, 1);
+	cbus_set_gpio_dataout(base, host->clk_gpio, 0);
+
+	spin_unlock_irqrestore(&host->lock, flags);
+
+	return is_read ? data : 0;
+}
+
+/*
+ * Read a given register from the device
+ */
+int cbus_read_reg(struct cbus_host *host, int dev, int reg)
+{
+	return cbus_host ? cbus_transfer(host, dev, reg, -1) : -ENODEV;
+}
+
+/*
+ * Write to a given register of the device
+ */
+int cbus_write_reg(struct cbus_host *host, int dev, int reg, u16 val)
+{
+	return cbus_host ? cbus_transfer(host, dev, reg, (int)val) : -ENODEV;
+}
+
+int __init cbus_bus_init(void)
+{
+	const struct omap_cbus_config * cbus_config;
+	struct cbus_host *chost;
+	int ret;
+
+	chost = kmalloc(sizeof (*chost), GFP_KERNEL);
+	if (chost == NULL)
+		return -ENOMEM;
+
+	memset(chost, 0, sizeof (*chost));
+
+	spin_lock_init(&chost->lock);
+
+	cbus_config = omap_get_config(OMAP_TAG_CBUS, struct omap_cbus_config);
+
+	if (cbus_config == NULL) {
+		printk(KERN_ERR "cbus: Unable to retrieve config data\n");
+		return -ENODATA;
+	}
+
+	chost->clk_gpio = cbus_config->clk_gpio;
+	chost->dat_gpio = cbus_config->dat_gpio;
+	chost->sel_gpio = cbus_config->sel_gpio;
+
+#ifdef CONFIG_ARCH_OMAP1
+	if (!OMAP_GPIO_IS_MPUIO(chost->clk_gpio) ||
+	    !OMAP_GPIO_IS_MPUIO(chost->dat_gpio) ||
+	    !OMAP_GPIO_IS_MPUIO(chost->sel_gpio)) {
+		printk(KERN_ERR "cbus: Only MPUIO pins supported\n");
+		ret = -ENODEV;
+		goto exit1;
+	}
+#endif
+
+	if ((ret = omap_request_gpio(chost->clk_gpio)) < 0)
+		goto exit1;
+
+	if ((ret = omap_request_gpio(chost->dat_gpio)) < 0)
+		goto exit2;
+
+	if ((ret = omap_request_gpio(chost->sel_gpio)) < 0)
+		goto exit3;
+
+	omap_set_gpio_dataout(chost->clk_gpio, 0);
+	omap_set_gpio_dataout(chost->sel_gpio, 1);
+
+	omap_set_gpio_direction(chost->clk_gpio, 0);
+	omap_set_gpio_direction(chost->dat_gpio, 1);
+	omap_set_gpio_direction(chost->sel_gpio, 0);
+
+	omap_set_gpio_dataout(chost->clk_gpio, 1);
+	omap_set_gpio_dataout(chost->clk_gpio, 0);
+
+	cbus_host = chost;
+
+	return 0;
+exit3:
+	omap_free_gpio(chost->dat_gpio);
+exit2:
+	omap_free_gpio(chost->clk_gpio);
+exit1:
+	kfree(chost);
+	return ret;
+}
+
+subsys_initcall(cbus_bus_init);
+
+EXPORT_SYMBOL(cbus_host);
+EXPORT_SYMBOL(cbus_read_reg);
+EXPORT_SYMBOL(cbus_write_reg);
+
+MODULE_DESCRIPTION("CBUS serial protocol");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Juha Yrjl, David Weinehall, and Mikko Ylinen");

drivers/cbus/cbus.h

+/*
+ * drivers/cbus/cbus.h
+ *
+ * Copyright (C) 2004, 2005 Nokia Corporation
+ *
+ * Written by Juha Yrjölä <juha.yrjola@nokia.com> and
+ *	      David Weinehall <david.weinehall@nokia.com>
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file "COPYING" in the main directory of this
+ * archive for more details.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef __DRIVERS_CBUS_CBUS_H
+#define __DRIVERS_CBUS_CBUS_H
+
+struct cbus_host {
+	int clk_gpio, dat_gpio, sel_gpio;
+        spinlock_t lock;
+};
+
+extern struct cbus_host *cbus_host;
+
+extern int cbus_read_reg(struct cbus_host *host, int dev, int reg);
+extern int cbus_write_reg(struct cbus_host *host, int dev, int reg, u16 val);
+
+#endif /* __DRIVERS_CBUS_CBUS_H */

drivers/cbus/retu-headset.c

+/**
+ * Retu/Vilma headset detection
+ *
+ * Copyright (C) 2006 Nokia Corporation
+ *
+ * Written by Juha Yrjl
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file "COPYING" in the main directory of this
+ * archive for more details.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/input.h>
+#include <linux/platform_device.h>
+
+#include "retu.h"
+
+#define RETU_ADC_CHANNEL_HOOKDET	0x05
+
+#define RETU_HEADSET_KEY		KEY_PHONE
+
+#define STATE_DISABLE_DET		1
+#define STATE_ENABLE_DET		2
+
+struct retu_headset {
+	struct platform_device *pdev;
+	struct input_dev *idev;
+	unsigned bias_enabled:1;
+
+	unsigned detection_enabled:1, pressed:1;
+	int detection_state;
+	struct timer_list enable_timer, detect_timer;
+	spinlock_t lock;
+};
+
+static void retu_headset_set_bias(int enable)
+{
+	if (enable) {
+		retu_set_clear_reg_bits(RETU_REG_AUDTXR,
+					(1 << 0) | (1 << 1), 0);
+		msleep(2);
+		retu_set_clear_reg_bits(RETU_REG_AUDTXR, 1 << 3, 0);
+	} else {
+		retu_set_clear_reg_bits(RETU_REG_AUDTXR, 0,
+				    (1 << 0) | (1 << 1) | (1 << 3));
+	}
+}
+
+static void retu_headset_enable(struct retu_headset *hs)
+{
+	if (hs->bias_enabled)
+		return;
+	hs->bias_enabled = 1;
+	retu_headset_set_bias(1);
+}
+
+static void retu_headset_disable(struct retu_headset *hs)
+{
+	if (!hs->bias_enabled)
+		return;
+	hs->bias_enabled = 0;
+	retu_headset_set_bias(0);
+}
+
+static void retu_headset_det_enable(struct retu_headset *hs)
+{
+	if (hs->detection_enabled)
+		return;
+	hs->detection_enabled = 1;
+	retu_set_clear_reg_bits(RETU_REG_CC1, (1 << 10) | (1 << 8), 0);
+	retu_enable_irq(RETU_INT_HOOK);
+}
+
+static void retu_headset_det_disable(struct retu_headset *hs)
+{
+	if (!hs->detection_enabled)
+		return;
+	hs->detection_enabled = 0;
+	retu_disable_irq(RETU_INT_HOOK);
+	del_timer_sync(&hs->enable_timer);
+	del_timer_sync(&hs->detect_timer);
+	if (hs->pressed)
+		input_report_key(hs->idev, RETU_HEADSET_KEY, 0);
+	retu_set_clear_reg_bits(RETU_REG_CC1, 0, (1 << 10) | (1 << 8));
+}
+
+static ssize_t retu_headset_hookdet_show(struct device *dev,
+					 struct device_attribute *attr,
+					 char *buf)
+{
+	int val;
+
+	val = retu_read_adc(RETU_ADC_CHANNEL_HOOKDET);
+	return sprintf(buf, "%d\n", val);
+}
+
+static DEVICE_ATTR(hookdet, S_IRUGO, retu_headset_hookdet_show, NULL);
+
+static ssize_t retu_headset_enable_show(struct device *dev,
+					struct device_attribute *attr,
+					char *buf)
+{
+	struct retu_headset *hs = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%u\n", hs->bias_enabled);
+}
+
+static ssize_t retu_headset_enable_store(struct device *dev,
+					 struct device_attribute *attr,
+					 const char *buf, size_t count)
+{
+	struct retu_headset *hs = dev_get_drvdata(dev);
+	int enable;
+
+	if (sscanf(buf, "%u", &enable) != 1)
+		return -EINVAL;
+	if (enable)
+		retu_headset_enable(hs);
+	else
+	        retu_headset_disable(hs);
+	return count;
+}
+
+static DEVICE_ATTR(enable, S_IRUGO | S_IWUSR | S_IWGRP,
+		   retu_headset_enable_show, retu_headset_enable_store);
+
+static ssize_t retu_headset_enable_det_show(struct device *dev,
+					    struct device_attribute *attr,
+					    char *buf)
+{
+	struct retu_headset *hs = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%u\n", hs->detection_enabled);
+}
+
+static ssize_t retu_headset_enable_det_store(struct device *dev,
+					     struct device_attribute *attr,
+					     const char *buf, size_t count)
+{
+	struct retu_headset *hs = dev_get_drvdata(dev);
+	int enable;
+
+	if (sscanf(buf, "%u", &enable) != 1)
+		return -EINVAL;
+	if (enable)
+		retu_headset_det_enable(hs);
+	else
+	        retu_headset_det_disable(hs);
+	return count;
+}
+
+static DEVICE_ATTR(enable_det, S_IRUGO | S_IWUSR | S_IWGRP,
+		   retu_headset_enable_det_show,
+		   retu_headset_enable_det_store);
+
+static void retu_headset_hook_interrupt(unsigned long arg)
+{
+	struct retu_headset *hs = (struct retu_headset *) arg;
+	unsigned long flags;
+	int was_pressed = 0;
+
+	retu_ack_irq(RETU_INT_HOOK);
+	spin_lock_irqsave(&hs->lock, flags);
+	if (!hs->pressed) {
+		/* Headset button was just pressed down. */
+		hs->pressed = 1;
+		input_report_key(hs->idev, RETU_HEADSET_KEY, 1);
+		was_pressed = 1;
+	}
+	spin_unlock_irqrestore(&hs->lock, flags);
+	if (was_pressed)
+		dev_info(&hs->pdev->dev, "button pressed\n");
+	retu_set_clear_reg_bits(RETU_REG_CC1, 0, (1 << 10) | (1 << 8));
+	mod_timer(&hs->enable_timer, jiffies + msecs_to_jiffies(50));
+}
+
+static void retu_headset_enable_timer(unsigned long arg)
+{
+	struct retu_headset *hs = (struct retu_headset *) arg;
+
+	retu_set_clear_reg_bits(RETU_REG_CC1, (1 << 10) | (1 << 8), 0);
+	mod_timer(&hs->detect_timer, jiffies + msecs_to_jiffies(350));
+}
+
+static void retu_headset_detect_timer(unsigned long arg)
+{
+	struct retu_headset *hs = (struct retu_headset *) arg;
+	unsigned long flags;
+
+	spin_lock_irqsave(&hs->lock, flags);
+	BUG_ON(!hs->pressed);
+	input_report_key(hs->idev, RETU_HEADSET_KEY, 0);
+	hs->pressed = 0;
+	spin_unlock_irqrestore(&hs->lock, flags);
+	dev_info(&hs->pdev->dev, "button released\n");
+}
+
+static int __init retu_headset_probe(struct platform_device *pdev)
+{
+	struct retu_headset *hs;
+	int r;
+
+	hs = kzalloc(sizeof(*hs), GFP_KERNEL);
+	if (hs == NULL)
+		return -ENOMEM;
+
+	hs->pdev = pdev;
+
+	hs->idev = input_allocate_device();
+	if (hs->idev == NULL) {
+		r = -ENOMEM;
+		goto err1;
+	}
+	hs->idev->name = "retu-headset";
+	hs->idev->cdev.dev = &pdev->dev;
+	hs->idev->private = hs;
+	set_bit(EV_KEY, hs->idev->evbit);
+	set_bit(RETU_HEADSET_KEY, hs->idev->keybit);
+	r = input_register_device(hs->idev);
+	if (r < 0)
+		goto err2;
+
+	r = device_create_file(&pdev->dev, &dev_attr_hookdet);
+	if (r < 0)
+		goto err3;
+	r = device_create_file(&pdev->dev, &dev_attr_enable);
+	if (r < 0)
+		goto err4;
+	r = device_create_file(&pdev->dev, &dev_attr_enable_det);
+	if (r < 0)
+		goto err5;
+	platform_set_drvdata(pdev, hs);
+
+	spin_lock_init(&hs->lock);
+	setup_timer(&hs->enable_timer, retu_headset_enable_timer,
+		    (unsigned long) hs);
+	setup_timer(&hs->detect_timer, retu_headset_detect_timer,
+		    (unsigned long) hs);
+
+	r = retu_request_irq(RETU_INT_HOOK, retu_headset_hook_interrupt,
+			     (unsigned long) hs, "hookdet");
+	if (r != 0) {
+		dev_err(&pdev->dev, "hookdet IRQ not available\n");
+		goto err6;
+	}
+	retu_disable_irq(RETU_INT_HOOK);
+	return 0;
+err6:
+	device_remove_file(&pdev->dev, &dev_attr_enable_det);
+err5:
+	device_remove_file(&pdev->dev, &dev_attr_enable);
+err4:
+	device_remove_file(&pdev->dev, &dev_attr_hookdet);
+err3:
+	input_unregister_device(hs->idev);
+err2:
+	input_free_device(hs->idev);
+err1:
+	kfree(hs);
+	return r;
+}
+
+static int retu_headset_remove(struct platform_device *pdev)
+{
+	struct retu_headset *hs = platform_get_drvdata(pdev);
+
+	device_remove_file(&pdev->dev, &dev_attr_hookdet);
+	device_remove_file(&pdev->dev, &dev_attr_enable);
+	device_remove_file(&pdev->dev, &dev_attr_enable_det);
+	retu_headset_disable(hs);
+	retu_headset_det_disable(hs);
+	retu_free_irq(RETU_INT_HOOK);
+	input_unregister_device(hs->idev);
+	input_free_device(hs->idev);
+	return 0;
+}
+
+static int retu_headset_suspend(struct platform_device *pdev, pm_message_t mesg)
+{
+	return 0;
+}
+
+static int retu_headset_resume(struct platform_device *pdev)
+{
+	return 0;
+}
+
+
+static struct platform_driver retu_headset_driver = {
+	.probe		= retu_headset_probe,
+	.remove		= retu_headset_remove,
+	.suspend	= retu_headset_suspend,
+	.resume		= retu_headset_resume,
+	.driver		= {
+		.name	= "retu-headset",
+	},
+};
+
+static int __init retu_headset_init(void)
+{
+	int r;
+
+	printk(KERN_INFO "Retu/Vilma headset driver initializing\n");
+
+	r = platform_driver_register(&retu_headset_driver);
+	if (r < 0)
+		return r;
+
+	return 0;
+}
+
+static void __exit retu_headset_exit(void)
+{
+	platform_driver_unregister(&retu_headset_driver);
+}
+
+module_init(retu_headset_init);
+module_exit(retu_headset_exit);
+
+MODULE_DESCRIPTION("Retu/Vilma headset detection");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Juha Yrjl");

drivers/cbus/retu-pwrbutton.c

+/**
+ * drivers/cbus/retu-pwrbutton.c
+ *
+ * Driver for sending retu power button event to input-layer
+ *
+ * Copyright (C) 2004 Nokia Corporation
+ *
+ * Written by Ari Saastamoinen <ari.saastamoinen@elektrobit.com>
+ *
+ * Contact Juha Yrjl <juha.yrjola@nokia.com>
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file "COPYING" in the main directory of this
+ * archive for more details.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/input.h>
+#include <linux/timer.h>
+#include <linux/jiffies.h>
+
+#include "retu.h"
+
+#define RETU_STATUS_PWRONX	(1 << 5)
+
+#define PWRBTN_DELAY		20
+#define PWRBTN_UP		0
+#define PWRBTN_PRESSED		1
+
+static int pwrbtn_state;
+static struct input_dev *pwrbtn_dev;
+static struct timer_list pwrbtn_timer;
+
+static void retubutton_timer_func(unsigned long arg)
+{
+	int state;
+
+	if (retu_read_reg(RETU_REG_STATUS) & RETU_STATUS_PWRONX)
+		state = PWRBTN_UP;
+	else
+		state = PWRBTN_PRESSED;
+
+	if (pwrbtn_state != state) {
+		input_report_key(pwrbtn_dev, KEY_POWER, state);
+		pwrbtn_state = state;
+	}
+}
+
+/**
+ * Interrupt function is called whenever power button key is pressed
+ * or released.
+ */
+static void retubutton_irq(unsigned long arg)
+{
+	retu_ack_irq(RETU_INT_PWR);
+	mod_timer(&pwrbtn_timer, jiffies + msecs_to_jiffies(PWRBTN_DELAY));
+}
+
+/**
+ * Init function.
+ * Allocates interrupt for power button and registers itself to input layer.
+ */
+static int __init retubutton_init(void)
+{
+	int irq;
+
+	printk(KERN_INFO "Retu power button driver initialized\n");
+	irq = RETU_INT_PWR;
+
+	init_timer(&pwrbtn_timer);
+	pwrbtn_timer.function = retubutton_timer_func;
+
+	if (retu_request_irq(irq, &retubutton_irq, 0, "PwrOnX") < 0) {
+		printk(KERN_ERR "%s@%s: Cannot allocate irq\n",
+		       __FUNCTION__, __FILE__);
+		return -EBUSY;
+	}
+
+	pwrbtn_dev = input_allocate_device();
+	if (!pwrbtn_dev)
+		return -ENOMEM;
+
+	pwrbtn_dev->evbit[0] = BIT(EV_KEY);
+	pwrbtn_dev->keybit[LONG(KEY_POWER)] = BIT(KEY_POWER);
+	pwrbtn_dev->name = "retu-pwrbutton";
+
+	input_register_device(pwrbtn_dev);
+
+	return 0;
+}
+
+/**
+ * Cleanup function which is called when driver is unloaded
+ */
+static void __exit retubutton_exit(void)
+{
+	retu_free_irq(RETU_INT_PWR);
+	del_timer_sync(&pwrbtn_timer);
+	input_unregister_device(pwrbtn_dev);
+}
+
+module_init(retubutton_init);
+module_exit(retubutton_exit);
+
+MODULE_DESCRIPTION("Retu Power Button");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Ari Saastamoinen");

drivers/cbus/retu-rtc.c

+/**
+ * drivers/cbus/retu-rtc.c
+ *
+ * Support for Retu RTC
+ *
+ * Copyright (C) 2004, 2005 Nokia Corporation
+ *
+ * Written by Paul Mundt <paul.mundt@nokia.com> and
+ *            Igor Stoppa <igor.stoppa@nokia.com>
+ *
+ * The Retu RTC is essentially a partial read-only RTC that gives us Retu's
+ * idea of what time actually is. It's left as a userspace excercise to map
+ * this back to time in the real world and ensure that calibration settings
+ * are sane to compensate for any horrible drift (on account of not being able
+ * to set the clock to anything).
+ *
+ * Days are semi-writeable. Namely, Retu will only track 255 days for us
+ * consecutively, after which the counter is explicitly stuck at 255 until
+ * someone comes along and clears it with a write. In the event that no one
+ * comes along and clears it, we no longer have any idea what day it is.
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file "COPYING" in the main directory of this
+ * archive for more details.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/completion.h>
+#include <linux/platform_device.h>
+#include <linux/mutex.h>
+#include <linux/workqueue.h>
+
+#include "cbus.h"
+#include "retu.h"
+
+static struct mutex retu_rtc_mutex;
+static u16 retu_rtc_alarm_expired;
+static u16 retu_rtc_reset_occurred;
+
+static DECLARE_COMPLETION(retu_rtc_exited);
+static DECLARE_COMPLETION(retu_rtc_sync);
+
+static void retu_rtc_barrier(void);
+
+static void retu_rtc_device_release(struct device *dev)
+{
+	complete(&retu_rtc_exited);
+}
+
+static ssize_t retu_rtc_time_show(struct device *dev, struct device_attribute *attr,
+				  char *buf)
+{
+	u16 dsr, hmr, dsr2;
+
+	mutex_lock(&retu_rtc_mutex);
+
+	do {
+		u16 dummy;
+
+		/*
+		 * Not being in_interrupt() for a retu rtc IRQ, we need to
+		 * read twice for consistency..
+		 */
+		dummy	= retu_read_reg(RETU_REG_RTCDSR);
+		dsr	= retu_read_reg(RETU_REG_RTCDSR);
+
+		dummy	= retu_read_reg(RETU_REG_RTCHMR);
+		hmr	= retu_read_reg(RETU_REG_RTCHMR);
+
+		dummy	= retu_read_reg(RETU_REG_RTCDSR);
+		dsr2	= retu_read_reg(RETU_REG_RTCDSR);
+	} while ((dsr != dsr2));
+
+	mutex_unlock(&retu_rtc_mutex);
+
+	/*
+	 * Format a 32-bit date-string for userspace
+	 *
+	 * days | hours | minutes | seconds
+	 *
+	 * 8 bits for each.
+	 *
+	 * This mostly sucks because days and seconds are tracked in RTCDSR
+	 * while hours and minutes are tracked in RTCHMR. And yes, there
+	 * really are no words that can describe an 8 bit day register (or
+	 * rather, none that will be reprinted here).
+	 */
+	return sprintf(buf, "0x%08x\n", (((dsr >> 8) & 0xff) << 24) |
+				        (((hmr >> 8) & 0x1f) << 16) |
+					 ((hmr & 0x3f) << 8) | (dsr & 0x3f));
+}
+
+static ssize_t retu_rtc_time_store(struct device *dev, struct device_attribute *attr,
+				   const char *buf, size_t count)
+{
+	mutex_lock(&retu_rtc_mutex);
+	/*
+	 * Writing anything to the day counter forces it to 0
+	 * The seconds counter would be cleared by resetting the minutes counter,
+	 * however this won't happen, since we are using the hh:mm counters as
+	 * a set of free running counters and the day counter as a multiple
+	 * overflow holder.
+	 */
+
+	/* Reset day counter, but keep Temperature Shutdown state */
+	retu_write_reg(RETU_REG_RTCDSR,
+		       retu_read_reg(RETU_REG_RTCDSR) & (1 << 6));
+
+	mutex_unlock(&retu_rtc_mutex);
+
+	return count;
+}
+
+static DEVICE_ATTR(time, S_IRUGO | S_IWUSR, retu_rtc_time_show,
+		   retu_rtc_time_store);
+
+
+static ssize_t retu_rtc_reset_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	/*
+	 * Returns the status of the rtc
+	 *
+	 * 0: no reset has occurred or the status has been cleared
+	 * 1: a reset has occurred
+	 *
+	 * RTC needs to be reset only when both main battery
+	 * _AND_ backup battery are discharged
+	 */
+	return sprintf(buf, "%u\n", retu_rtc_reset_occurred);
+}
+
+static void retu_rtc_do_reset(void)
+{
+	u16 ccr1;
+
+	ccr1 = retu_read_reg(RETU_REG_CC1);
+	/* RTC in reset */
+	retu_write_reg(RETU_REG_CC1, ccr1 | 0x0001);
+	/* RTC in normal operating mode */
+	retu_write_reg(RETU_REG_CC1, ccr1 & ~0x0001);
+
+	retu_rtc_barrier();
+	/* Disable alarm and RTC WD */
+	retu_write_reg(RETU_REG_RTCHMAR, 0x7f3f);
+	/* Set Calibration register to default value */
+	retu_write_reg(RETU_REG_RTCCALR, 0x00c0);
+
+	retu_rtc_alarm_expired = 0;
+	retu_rtc_reset_occurred = 1;
+}
+
+static ssize_t retu_rtc_reset_store(struct device *dev, struct device_attribute *attr,
+				    const char *buf, size_t count)
+{
+	unsigned choice;
+
+	if(sscanf(buf, "%u", &choice) != 1)
+		return count;
+	mutex_lock(&retu_rtc_mutex);
+	if (choice == 0)
+		retu_rtc_reset_occurred = 0;
+	else if (choice == 1)
+		retu_rtc_do_reset();
+	mutex_unlock(&retu_rtc_mutex);
+	return count;
+}
+
+static DEVICE_ATTR(reset, S_IRUGO | S_IWUSR, retu_rtc_reset_show,
+		   retu_rtc_reset_store);
+
+static ssize_t retu_rtc_alarm_show(struct device *dev, struct device_attribute *attr,
+				   char *buf)
+{
+	u16 chmar;
+	ssize_t retval;
+
+	mutex_lock(&retu_rtc_mutex);
+	/*
+	 * Format a 16-bit date-string for userspace
+	 *
+	 * hours | minutes
+	 * 8 bits for each.
+	 */
+	chmar = retu_read_reg(RETU_REG_RTCHMAR);
+	/* No shifting needed, only masking unrelated bits */
+	retval = sprintf(buf, "0x%04x\n", chmar & 0x1f3f);
+	mutex_unlock(&retu_rtc_mutex);
+
+	return retval;
+}
+
+static ssize_t retu_rtc_alarm_store(struct device *dev, struct device_attribute *attr,
+				    const char *buf, size_t count)
+{
+	u16 chmar;
+	unsigned alrm;
+	unsigned hours;
+	unsigned minutes;
+
+	mutex_lock(&retu_rtc_mutex);
+
+	if(sscanf(buf, "%x", &alrm) != 1)
+		return count;
+	hours = (alrm >> 8) & 0x001f;
+	minutes = (alrm >> 0) & 0x003f;
+	if ((hours < 24 && minutes < 60) || (hours == 24 && minutes == 60)) {
+		/*
+		 * OK, the time format for the alarm is valid (including the
+		 * disabling values)
+		 */
+		/* Keeps the RTC watchdog status */
+		chmar = retu_read_reg(RETU_REG_RTCHMAR) & 0x6000;
+		chmar |= alrm & 0x1f3f;	/* Stores the requested alarm */
+		retu_rtc_barrier();
+		retu_write_reg(RETU_REG_RTCHMAR, chmar);
+		/* If the alarm is being disabled */
+		if (hours == 24 && minutes == 60) {
+			/* disable the interrupt */
+			retu_disable_irq(RETU_INT_RTCA);
+			retu_rtc_alarm_expired = 0;
+		} else
+			/* enable the interrupt */
+			retu_enable_irq(RETU_INT_RTCA);
+	}
+	mutex_unlock(&retu_rtc_mutex);
+
+	return count;
+}
+
+static DEVICE_ATTR(alarm, S_IRUGO | S_IWUSR, retu_rtc_alarm_show,
+		   retu_rtc_alarm_store);
+
+static ssize_t retu_rtc_alarm_expired_show(struct device *dev, struct device_attribute *attr,
+					   char *buf)
+{
+	ssize_t retval;
+
+	retval = sprintf(buf, "%u\n", retu_rtc_alarm_expired);
+
+	return retval;
+}
+
+static ssize_t retu_rtc_alarm_expired_store(struct device *dev, struct device_attribute *attr,
+					    const char *buf, size_t count)
+{
+	retu_rtc_alarm_expired = 0;
+
+	return count;
+}
+
+static DEVICE_ATTR(alarm_expired, S_IRUGO | S_IWUSR, retu_rtc_alarm_expired_show,
+		   retu_rtc_alarm_expired_store);
+
+
+static ssize_t retu_rtc_cal_show(struct device *dev, struct device_attribute *attr,
+				 char *buf)
+{
+	u16 rtccalr1;
+
+	mutex_lock(&retu_rtc_mutex);
+	rtccalr1 = retu_read_reg(RETU_REG_RTCCALR);
+	mutex_unlock(&retu_rtc_mutex);
+
+	/*
+	 * Shows the status of the Calibration Register.
+	 *
+	 * Default, after power loss: 0x0000
+	 * Default, for R&D: 0x00C0
+	 * Default, for factory: 0x00??
+	 *
+	 */
+	return sprintf(buf, "0x%04x\n", rtccalr1 & 0x00ff);
+}
+
+static ssize_t retu_rtc_cal_store(struct device *dev, struct device_attribute *attr,
+				  const char *buf, size_t count)
+{
+	unsigned calibration_value;
+
+	if (sscanf(buf, "%x", &calibration_value) != 1)
+		return count;
+
+	mutex_lock(&retu_rtc_mutex);
+	retu_rtc_barrier();
+	retu_write_reg(RETU_REG_RTCCALR, calibration_value & 0x00ff);
+	mutex_unlock(&retu_rtc_mutex);
+
+	return count;
+}
+
+static DEVICE_ATTR(cal, S_IRUGO | S_IWUSR, retu_rtc_cal_show,
+		   retu_rtc_cal_store);
+
+static struct device_driver retu_rtc_driver;
+
+static void retu_rtca_disable(void)
+{
+	retu_disable_irq(RETU_INT_RTCA);
+	retu_rtc_alarm_expired = 1;
+	retu_rtc_barrier();
+	retu_write_reg(RETU_REG_RTCHMAR, (24 << 8) | 60);
+}
+
+static void retu_rtca_expired(struct work_struct *unused)
+{
+	retu_rtca_disable();
+	sysfs_notify(&retu_rtc_driver.kobj, NULL, "alarm_expired");
+}
+
+DECLARE_WORK(retu_rtca_work, retu_rtca_expired);
+
+/*
+ * RTCHMR RTCHMAR RTCCAL must be accessed within 0.9 s since the seconds
+ * interrupt has been signaled in the IDR register
+ */
+static void retu_rtcs_interrupt(unsigned long unused)
+{
+	retu_ack_irq(RETU_INT_RTCS);
+	complete(&retu_rtc_sync);
+}
+
+static void retu_rtca_interrupt(unsigned long unused)
+{
+	retu_ack_irq(RETU_INT_RTCA);
+	schedule_work(&retu_rtca_work);
+}
+
+static int retu_rtc_init_irq(void)
+{
+	int ret;
+
+	ret = retu_request_irq(RETU_INT_RTCS, retu_rtcs_interrupt, 0, "RTCS");
+	if (ret != 0)
+		return ret;
+	/*
+	 * We will take care of enabling and disabling the interrupt
+	 * elsewhere, so leave it off by default..
+	 */
+	retu_disable_irq(RETU_INT_RTCS);
+
+	ret = retu_request_irq(RETU_INT_RTCA, retu_rtca_interrupt, 0, "RTCA");
+	if (ret != 0) {
+		retu_free_irq(RETU_INT_RTCS);
+		return ret;
+	}
+	retu_disable_irq(RETU_INT_RTCA);
+
+	return 0;
+}
+
+
+static int __devinit retu_rtc_probe(struct device *dev)
+{
+	int r;
+
+	retu_rtc_alarm_expired = retu_read_reg(RETU_REG_IDR) &
+					       (0x1 << RETU_INT_RTCA);
+
+	if ((r = retu_rtc_init_irq()) != 0)
+		return r;
+
+	mutex_init(&retu_rtc_mutex);
+
+	/* If the calibration register is zero, we've probably lost
+	 * power */
+	if (retu_read_reg(RETU_REG_RTCCALR) & 0x00ff)
+		retu_rtc_reset_occurred = 0;
+	else
+		retu_rtc_do_reset();
+
+	if ((r = device_create_file(dev, &dev_attr_time)) != 0)
+		return r;
+	else if ((r = device_create_file(dev, &dev_attr_reset)) != 0)
+		goto err_unregister_time;
+	else if ((r = device_create_file(dev, &dev_attr_alarm)) != 0)
+		goto err_unregister_reset;
+	else if ((r = device_create_file(dev, &dev_attr_alarm_expired)) != 0)
+		goto err_unregister_alarm;
+	else if ((r = device_create_file(dev, &dev_attr_cal)) != 0)
+		goto err_unregister_alarm_expired;
+	else
+		return r;
+
+err_unregister_alarm_expired:
+	device_remove_file(dev, &dev_attr_alarm_expired);
+err_unregister_alarm:
+	device_remove_file(dev, &dev_attr_alarm);
+err_unregister_reset:
+	device_remove_file(dev, &dev_attr_reset);
+err_unregister_time:
+	device_remove_file(dev, &dev_attr_time);
+	return r;
+}
+
+static int __devexit retu_rtc_remove(struct device *dev)
+{
+	retu_disable_irq(RETU_INT_RTCS);
+	retu_free_irq(RETU_INT_RTCS);
+	retu_free_irq(RETU_INT_RTCA);
+	device_remove_file(dev, &dev_attr_cal);
+	device_remove_file(dev, &dev_attr_alarm_expired);
+	device_remove_file(dev, &dev_attr_alarm);
+	device_remove_file(dev, &dev_attr_reset);
+	device_remove_file(dev, &dev_attr_time);
+	return 0;
+}
+
+static struct device_driver retu_rtc_driver = {
+	.name		= "retu-rtc",
+	.bus		= &platform_bus_type,
+	.probe		= retu_rtc_probe,
+	.remove		= __devexit_p(retu_rtc_remove),
+};
+
+static struct platform_device retu_rtc_device = {
+	.name		= "retu-rtc",
+	.id		= -1,
+	.dev		= {
+		.release	= retu_rtc_device_release,
+	},
+};
+
+/* This function provides syncronization with the RTCS interrupt handler */
+static void retu_rtc_barrier(void)
+{
+	init_completion(&retu_rtc_sync);
+	retu_ack_irq(RETU_INT_RTCS);
+	retu_enable_irq(RETU_INT_RTCS);
+	wait_for_completion(&retu_rtc_sync);
+	retu_disable_irq(RETU_INT_RTCS);
+}
+
+static int __init retu_rtc_init(void)
+{
+	int ret;
+
+	init_completion(&retu_rtc_exited);
+
+	if ((ret = driver_register(&retu_rtc_driver)) != 0)
+		return ret;
+
+	if ((ret = platform_device_register(&retu_rtc_device)) != 0)
+		goto err_unregister_driver;
+
+	return 0;
+
+err_unregister_driver:
+	driver_unregister(&retu_rtc_driver);
+	return ret;
+}
+
+static void __exit retu_rtc_exit(void)
+{
+	platform_device_unregister(&retu_rtc_device);
+	driver_unregister(&retu_rtc_driver);
+
+	wait_for_completion(&retu_rtc_exited);
+}
+
+module_init(retu_rtc_init);
+module_exit(retu_rtc_exit);
+
+MODULE_DESCRIPTION("Retu RTC");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Paul Mundt and Igor Stoppa");

drivers/cbus/retu-user.c

+/**
+ * drivers/cbus/retu-user.c
+ *
+ * Retu user space interface functions
+ *
+ * Copyright (C) 2004, 2005 Nokia Corporation
+ *
+ * Written by Mikko Ylinen <mikko.k.ylinen@nokia.com>
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file "COPYING" in the main directory of this
+ * archive for more details.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>
+#include <linux/poll.h>
+#include <linux/list.h>
+#include <linux/spinlock.h>
+#include <linux/mutex.h>
+
+#include <asm/uaccess.h>
+
+#include "retu.h"
+
+#include "user_retu_tahvo.h"
+
+/* Maximum size of IRQ node buffer/pool */
+#define RETU_MAX_IRQ_BUF_LEN	16
+
+#define PFX			"retu-user: "
+
+/* Bitmap for marking the interrupt sources as having the handlers */
+static u32 retu_irq_bits;
+
+/* For allowing only one user process to subscribe to the retu interrupts */
+static struct file *retu_irq_subscr = NULL;
+
+/* For poll and IRQ passing */
+struct retu_irq {
+	u32 id;
+	struct list_head node;
+};
+
+static spinlock_t retu_irqs_lock;
+static struct retu_irq *retu_irq_block;
+static LIST_HEAD(retu_irqs);
+static LIST_HEAD(retu_irqs_reserve);
+
+/* Wait queue - used when user wants to read the device */
+DECLARE_WAIT_QUEUE_HEAD(retu_user_waitqueue);
+
+/* Semaphore to protect irq subscription sequence */
+static struct mutex retu_mutex;
+
+/* This array specifies RETU register types (read/write/toggle) */
+static const u8 retu_access_bits[] = {
+	1,
+	4,
+	3,
+	3,
+	1,
+	3,
+	3,
+	0,
+	3,
+	3,
+	3,
+	3,
+	3,
+	3,
+	3,
+	4,
+	4,
+	3,
+	0,
+	0,
+	0,
+	0,
+	1,
+	3,
+	3,
+	3,
+	3,
+	3,
+	3,
+	3,
+	3,
+	3
+};
+
+/*
+ * The handler for all RETU interrupts.
+ *
+ * arg is the interrupt source in RETU.
+ */
+static void retu_user_irq_handler(unsigned long arg)
+{
+	struct retu_irq *irq;
+
+	retu_ack_irq(arg);
+
+	spin_lock(&retu_irqs_lock);
+	if (list_empty(&retu_irqs_reserve)) {
+		spin_unlock(&retu_irqs_lock);
+		return;
+	}
+	irq = list_entry((&retu_irqs_reserve)->next, struct retu_irq, node);
+	irq->id = arg;
+	list_move_tail(&irq->node, &retu_irqs);
+	spin_unlock(&retu_irqs_lock);
+
+	/* wake up waiting thread */
+	wake_up(&retu_user_waitqueue);
+}
+
+/*
+ * This routine sets up the interrupt handler and marks an interrupt source
+ * in RETU as a candidate for signal delivery to the user process.
+ */
+static int retu_user_subscribe_to_irq(int id, struct file *filp)
+{
+	int ret;
+
+	mutex_lock(&retu_mutex);
+	if ((retu_irq_subscr != NULL) && (retu_irq_subscr != filp)) {
+		mutex_unlock(&retu_mutex);
+		return -EBUSY;
+	}
+	/* Store the file pointer of the first user process registering IRQs */
+	retu_irq_subscr = filp;
+	mutex_unlock(&retu_mutex);
+
+	if (retu_irq_bits & (1 << id))
+		return 0;
+
+	ret = retu_request_irq(id, retu_user_irq_handler, id, "");
+	if (ret < 0)
+		return ret;
+
+	/* Mark that this interrupt has a handler */
+	retu_irq_bits |= 1 << id;
+
+	return 0;
+}
+
+/*
+ * Unregisters all RETU interrupt handlers.
+ */
+static void retu_unreg_irq_handlers(void)
+{
+	int id;
+
+	if (!retu_irq_bits)
+		return;
+
+	for (id = 0; id < MAX_RETU_IRQ_HANDLERS; id++)
+		if (retu_irq_bits & (1 << id))
+			retu_free_irq(id);
+
+	retu_irq_bits = 0;
+}
+
+/*
+ * Write to RETU register.
+ * Returns 0 upon success, a negative error value otherwise.
+ */
+static int retu_user_write_with_mask(u32 field, u16 value)
+{
+	u32 mask;
+	u32 reg;
+	u_short tmp;
+	unsigned long flags;
+
+	mask = MASK(field);
+	reg = REG(field);
+
+	/* Detect bad mask and reg */
+	if (mask == 0 || reg > RETU_REG_MAX ||
+	    retu_access_bits[reg] == READ_ONLY) {
+		printk(KERN_ERR PFX "invalid arguments (reg=%#x, mask=%#x)\n",
+		       reg, mask);
+		return -EINVAL;
+	}
+
+	/* Justify value according to mask */
+	while (!(mask & 1)) {
+		value = value << 1;
+		mask = mask >> 1;
+	}
+
+	spin_lock_irqsave(&retu_lock, flags);
+	if (retu_access_bits[reg] == TOGGLE) {
+		/* No need to detect previous content of register */
+		tmp = 0;
+	} else {
+		/* Read current value of register */
+		tmp = retu_read_reg(reg);
+	}
+
+	/* Generate new value */
+	tmp = (tmp & ~MASK(field)) | (value & MASK(field));
+	/* Write data to RETU */
+	retu_write_reg(reg, tmp);
+	spin_unlock_irqrestore(&retu_lock, flags);
+
+	return 0;
+}
+
+/*
+ * Read RETU register.
+ */
+static u32 retu_user_read_with_mask(u32 field)
+{
+	u_short value;
+	u32 mask, reg;
+
+	mask = MASK(field);
+	reg = REG(field);
+
+	/* Detect bad mask and reg */
+	if (mask == 0 || reg > RETU_REG_MAX) {
+		printk(KERN_ERR PFX "invalid arguments (reg=%#x, mask=%#x)\n",
+		       reg, mask);
+		return -EINVAL;
+	}
+
+	/* Read the register */
+	value = retu_read_reg(reg) & mask;
+
+	/* Right justify value */
+	while (!(mask & 1)) {
+		value = value >> 1;
+		mask = mask >> 1;
+	}
+
+	return value;
+}
+
+/*
+ * Close device
+ */
+static int retu_close(struct inode *inode, struct file *filp)
+{
+	/* Unregister all interrupts that have been registered */
+	if (retu_irq_subscr == filp) {
+		retu_unreg_irq_handlers();
+		retu_irq_subscr = NULL;
+	}
+
+	return 0;
+}
+
+/*
+ * Device control (ioctl)
+ */
+static int retu_ioctl(struct inode *inode, struct file *filp,
+		      unsigned int cmd, unsigned long arg)
+{
+	struct retu_tahvo_write_parms par;
+	int ret;
+
+	switch (cmd) {
+	case URT_IOCT_IRQ_SUBSCR:
+		return retu_user_subscribe_to_irq(arg, filp);
+	case RETU_IOCH_READ:
+		return retu_user_read_with_mask(arg);
+	case RETU_IOCX_WRITE:
+		ret = copy_from_user(&par, (void __user *) arg, sizeof(par));
+		if (ret)
+			printk(KERN_ERR "copy_from_user failed: %d\n", ret);
+		par.result = retu_user_write_with_mask(par.field, par.value);
+		ret = copy_to_user((void __user *) arg, &par, sizeof(par));
+		if (ret)
+			printk(KERN_ERR "copy_to_user failed: %d\n", ret);
+		break;
+	case RETU_IOCH_ADC_READ:
+		return retu_read_adc(arg);
+	default:
+		return -ENOIOCTLCMD;
+	}
+	return 0;
+}
+
+/*
+ * Read from device
+ */
+static ssize_t retu_read(struct file *filp, char *buf, size_t count,
+			 loff_t * offp)
+{
+	struct retu_irq *irq;
+
+	u32 nr, i;
+
+	/* read not permitted if neither filp nor anyone has registered IRQs */
+	if (retu_irq_subscr != filp)
+		return -EPERM;
+
+	if ((count < sizeof(u32)) || ((count % sizeof(u32)) != 0))
+		return -EINVAL;
+
+	nr = count / sizeof(u32);
+
+	for (i = 0; i < nr; i++) {
+		unsigned long flags;
+		u32 irq_id;
+		int ret;
+
+		ret = wait_event_interruptible(retu_user_waitqueue,
+					       !list_empty(&retu_irqs));
+		if (ret < 0)
+			return ret;
+
+		spin_lock_irqsave(&retu_irqs_lock, flags);
+		irq = list_entry((&retu_irqs)->next, struct retu_irq, node);
+		irq_id = irq->id;
+		list_move(&irq->node, &retu_irqs_reserve);
+		spin_unlock_irqrestore(&retu_irqs_lock, flags);
+
+		ret = copy_to_user(buf + i * sizeof(irq_id), &irq_id,
+				   sizeof(irq_id));
+		if (ret)
+			printk(KERN_ERR "copy_to_user failed: %d\n", ret);
+	}
+
+	return count;
+}
+
+/*
+ * Poll method
+ */
+static unsigned retu_poll(struct file *filp, struct poll_table_struct *pt)
+{
+	if (!list_empty(&retu_irqs))
+		return POLLIN;
+
+	poll_wait(filp, &retu_user_waitqueue, pt);
+
+	if (!list_empty(&retu_irqs))
+		return POLLIN;
+	else
+		return 0;
+}
+
+static struct file_operations retu_user_fileops = {
+	.owner = THIS_MODULE,
+	.ioctl = retu_ioctl,
+	.read = retu_read,
+	.release = retu_close,
+	.poll = retu_poll
+};
+
+static struct miscdevice retu_device = {
+	.minor = MISC_DYNAMIC_MINOR,
+	.name = "retu",
+	.fops = &retu_user_fileops
+};
+
+/*
+ * Initialization
+ *
+ * @return 0 if successful, error value otherwise.
+ */
+int retu_user_init(void)
+{
+	struct retu_irq *irq;
+	int res, i;
+
+	irq = kmalloc(sizeof(*irq) * RETU_MAX_IRQ_BUF_LEN, GFP_KERNEL);
+	if (irq == NULL) {
+		printk(KERN_ERR PFX "kmalloc failed\n");
+		return -ENOMEM;
+	}
+	memset(irq, 0, sizeof(*irq) * RETU_MAX_IRQ_BUF_LEN);
+	for (i = 0; i < RETU_MAX_IRQ_BUF_LEN; i++)
+		list_add(&irq[i].node, &retu_irqs_reserve);
+
+	retu_irq_block = irq;
+
+	spin_lock_init(&retu_irqs_lock);
+	mutex_init(&retu_mutex);
+
+	/* Request a misc device */
+	res = misc_register(&retu_device);
+	if (res < 0) {
+		printk(KERN_ERR PFX "unable to register misc device for %s\n",
+		       retu_device.name);
+		kfree(irq);
+		return res;
+	}
+
+	return 0;
+}
+
+/*
+ * Cleanup.
+ */
+void retu_user_cleanup(void)
+{
+	/* Unregister our misc device */
+	misc_deregister(&retu_device);
+	/* Unregister and disable all RETU interrupts used by this module */
+	retu_unreg_irq_handlers();
+	kfree(retu_irq_block);
+}
+
+MODULE_DESCRIPTION("Retu ASIC user space functions");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Mikko Ylinen");

drivers/cbus/retu-wdt.c

+/**
+ * drivers/cbus/retu-wdt.c
+ *
+ * Driver for Retu watchdog
+ *
+ * Copyright (C) 2004, 2005 Nokia Corporation
+ *
+ * Written by Amit Kucheria <amit.kucheria@nokia.com>
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file "COPYING" in the main directory of this
+ * archive for more details.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/init.h>
+
+#include <linux/completion.h>
+#include <linux/errno.h>
+#include <linux/moduleparam.h>
+#include <linux/platform_device.h>
+
+#include "cbus.h"
+#include "retu.h"
+
+/* Watchdog timeout in seconds */
+#define RETU_WDT_MIN_TIMER 0
+#define RETU_WDT_DEFAULT_TIMER 32
+#define RETU_WDT_MAX_TIMER 63
+
+static struct completion retu_wdt_completion;
+static DECLARE_MUTEX(retu_wdt_mutex);	/* Avoid simultaneous writes to watchdog register */
+
+static unsigned int period_val = RETU_WDT_DEFAULT_TIMER;	/* Current period of watchdog */
+static int counter_param = RETU_WDT_MAX_TIMER;
+
+static int retu_modify_counter(unsigned int new)
+{
+	int ret = 0;
+
+	if (new < RETU_WDT_MIN_TIMER || new > RETU_WDT_MAX_TIMER)
+		return -EINVAL;
+
+	down_interruptible(&retu_wdt_mutex);
+
+	period_val = new;
+	retu_write_reg(RETU_REG_WATCHDOG, (u16)period_val);
+
+	up(&retu_wdt_mutex);
+	return ret;
+}
+
+static ssize_t retu_wdt_period_show(struct device *dev, struct device_attribute *attr,
+				    char *buf)
+{
+	/* Show current max counter */
+	return sprintf(buf, "%u\n", (u16)period_val);
+}
+
+static ssize_t retu_wdt_period_store(struct device *dev, struct device_attribute *attr,
+				     const char *buf, size_t count)
+{
+	unsigned int new_period;
+	int ret;
+
+	if (sscanf(buf, "%u", &new_period) != 1) {
+		printk(KERN_ALERT "retu_wdt_period_store: Invalid input\n");
+		return -EINVAL;
+	}
+
+	ret = retu_modify_counter(new_period);
+	if (ret < 0)
+		return ret;
+
+	return strnlen(buf, count);
+}
+
+static ssize_t retu_wdt_counter_show(struct device *dev, struct device_attribute *attr,
+				     char *buf)
+{
+	u16 counter;
+
+	/* Show current value in watchdog counter */
+	counter = retu_read_reg(RETU_REG_WATCHDOG);
+
+	/* Only the 5 LSB are important */
+	return snprintf(buf, PAGE_SIZE, "%u\n", (counter & 0x3F));
+}
+
+static DEVICE_ATTR(period, S_IRUGO | S_IWUSR, retu_wdt_period_show, \
+                   retu_wdt_period_store);
+static DEVICE_ATTR(counter, S_IRUGO, retu_wdt_counter_show, NULL);
+
+static int __devinit retu_wdt_probe(struct device *dev)
+{
+	int ret;
+
+	ret = device_create_file(dev, &dev_attr_period);
+	if (ret) {
+		printk(KERN_ERR "retu_wdt_probe: Error creating sys device file: period\n");
+		return ret;
+	}
+
+	ret = device_create_file(dev, &dev_attr_counter);
+	if (ret) {
+		device_remove_file(dev, &dev_attr_period);
+		printk(KERN_ERR "retu_wdt_probe: Error creating sys device file: counter\n");
+	}
+
+	return ret;
+}
+
+static int __devexit retu_wdt_remove(struct device *dev)
+{
+	device_remove_file(dev, &dev_attr_period);
+	device_remove_file(dev, &dev_attr_counter);
+	return 0;
+}
+
+static void retu_wdt_device_release(struct device *dev)
+{
+	complete(&retu_wdt_completion);
+}
+
+static struct platform_device retu_wdt_device = {
+	.name = "retu-watchdog",
+	.id = -1,
+	.dev = {
+		.release = retu_wdt_device_release,
+	},
+};
+
+static struct device_driver retu_wdt_driver = {
+	.name = "retu-watchdog",
+	.bus = &platform_bus_type,
+	.probe = retu_wdt_probe,
+	.remove = __devexit_p(retu_wdt_remove),
+};
+
+static int __init retu_wdt_init(void)
+{
+	int ret;
+
+	init_completion(&retu_wdt_completion);
+
+	ret = driver_register(&retu_wdt_driver);
+	if (ret)
+		return ret;
+
+	ret = platform_device_register(&retu_wdt_device);
+	if (ret)
+		goto exit1;
+
+	/* passed as module parameter? */
+	ret = retu_modify_counter(counter_param);
+	if (ret == -EINVAL) {
+		ret = retu_modify_counter(RETU_WDT_DEFAULT_TIMER);
+		printk(KERN_INFO
+		       "retu_wdt_init: Intializing to default value\n");
+	}
+
+	printk(KERN_INFO "Retu watchdog driver initialized\n");
+	return ret;
+
+exit1:
+	driver_unregister(&retu_wdt_driver);
+	wait_for_completion(&retu_wdt_completion);
+
+	return ret;
+}
+
+static void __exit retu_wdt_exit(void)
+{
+	platform_device_unregister(&retu_wdt_device);
+	driver_unregister(&retu_wdt_driver);
+
+	wait_for_completion(&retu_wdt_completion);
+}
+
+module_init(retu_wdt_init);
+module_exit(retu_wdt_exit);
+module_param(counter_param, int, 0);
+
+MODULE_DESCRIPTION("Retu WatchDog");
+MODULE_AUTHOR("Amit Kucheria");
+MODULE_LICENSE("GPL");
+

drivers/cbus/retu.c

+/**
+ * drivers/cbus/retu.c
+ *
+ * Support functions for Retu ASIC
+ *
+ * Copyright (C) 2004, 2005 Nokia Corporation
+ *
+ * Written by Juha Yrjl <juha.yrjola@nokia.com>,
+ *	      David Weinehall <david.weinehall@nokia.com>, and
+ *	      Mikko Ylinen <mikko.k.ylinen@nokia.com>
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file "COPYING" in the main directory of this
+ * archive for more details.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/device.h>
+#include <linux/miscdevice.h>
+#include <linux/poll.h>
+#include <linux/fs.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+
+#include <asm/uaccess.h>
+
+#include <asm/arch/mux.h>
+#include <asm/arch/gpio.h>
+#include <asm/arch/board.h>
+
+#include "cbus.h"
+#include "retu.h"
+
+#define RETU_ID			0x01
+#define PFX			"retu: "
+
+static int retu_initialized;
+static int retu_irq_pin;
+static int retu_is_vilma;
+
+static struct tasklet_struct retu_tasklet;
+spinlock_t retu_lock = SPIN_LOCK_UNLOCKED;
+
+static struct completion device_release;
+
+struct retu_irq_handler_desc {
+	int (*func)(unsigned long);
+	unsigned long arg;
+	char name[8];
+};
+
+static struct retu_irq_handler_desc retu_irq_handlers[MAX_RETU_IRQ_HANDLERS];
+
+/**
+ * retu_read_reg - Read a value from a register in Retu
+ * @reg: the register to read from
+ *
+ * This function returns the contents of the specified register
+ */
+int retu_read_reg(int reg)
+{
+	BUG_ON(!retu_initialized);
+	return cbus_read_reg(cbus_host, RETU_ID, reg);
+}
+
+/**
+ * retu_write_reg - Write a value to a register in Retu
+ * @reg: the register to write to
+ * @reg: the value to write to the register
+ *
+ * This function writes a value to the specified register
+ */
+void retu_write_reg(int reg, u16 val)
+{
+	BUG_ON(!retu_initialized);
+	cbus_write_reg(cbus_host, RETU_ID, reg, val);
+}
+
+void retu_set_clear_reg_bits(int reg, u16 set, u16 clear)
+{
+	unsigned long flags;
+	u16 w;
+
+	spin_lock_irqsave(&retu_lock, flags);
+	w = retu_read_reg(reg);
+	w &= ~clear;
+	w |= set;
+	retu_write_reg(reg, w);
+	spin_unlock_irqrestore(&retu_lock, flags);
+}
+
+#define ADC_MAX_CHAN_NUMBER	13
+
+int retu_read_adc(int channel)
+{
+	unsigned long flags;
+	int res;
+
+	if (channel < 0 || channel > ADC_MAX_CHAN_NUMBER)
+		return -EINVAL;
+
+	spin_lock_irqsave(&retu_lock, flags);
+	/* Select the channel and read result */
+	retu_write_reg(RETU_REG_ADCR, channel << 10);
+	res = retu_read_reg(RETU_REG_ADCR) & 0x3ff;
+	/* Unlock retu */
+	spin_unlock_irqrestore(&retu_lock, flags);
+
+	return res;
+}
+
+
+static u16 retu_disable_bogus_irqs(u16 mask)
+{
+       int i;
+
+       for (i = 0; i < MAX_RETU_IRQ_HANDLERS; i++) {
+               if (mask & (1 << i))
+                       continue;
+               if (retu_irq_handlers[i].func != NULL)
+                       continue;
+               /* an IRQ was enabled but we don't have a handler for it */
+               printk(KERN_INFO PFX "disabling bogus IRQ %d\n", i);
+               mask |= (1 << i);
+       }
+       return mask;
+}
+
+/*
+ * Disable given RETU interrupt
+ */
+void retu_disable_irq(int id)
+{
+	unsigned long flags;
+	u16 mask;
+
+	spin_lock_irqsave(&retu_lock, flags);
+	mask = retu_read_reg(RETU_REG_IMR);
+	mask |= 1 << id;
+	mask = retu_disable_bogus_irqs(mask);
+	retu_write_reg(RETU_REG_IMR, mask);
+	spin_unlock_irqrestore(&retu_lock, flags);
+}
+
+/*
+ * Enable given RETU interrupt
+ */
+void retu_enable_irq(int id)
+{
+	unsigned long flags;
+	u16 mask;
+
+	if (id == 3) {
+		printk("Enabling Retu IRQ %d\n", id);
+		dump_stack();
+	}
+	spin_lock_irqsave(&retu_lock, flags);
+	mask = retu_read_reg(RETU_REG_IMR);
+	mask &= ~(1 << id);
+	mask = retu_disable_bogus_irqs(mask);
+	retu_write_reg(RETU_REG_IMR, mask);
+	spin_unlock_irqrestore(&retu_lock, flags);
+}
+
+/*
+ * Acknowledge given RETU interrupt
+ */
+void retu_ack_irq(int id)
+{
+	retu_write_reg(RETU_REG_IDR, 1 << id);
+}
+
+/*
+ * RETU interrupt handler. Only schedules the tasklet.
+ */
+static irqreturn_t retu_irq_handler(int irq, void *dev_id)
+{
+	tasklet_schedule(&retu_tasklet);
+	return IRQ_HANDLED;
+}
+
+/*
+ * Tasklet handler
+ */
+static void retu_tasklet_handler(unsigned long data)
+{
+	struct retu_irq_handler_desc *hnd;
+	u16 id;
+	u16 im;
+	int i;
+
+	for (;;) {
+		id = retu_read_reg(RETU_REG_IDR);
+		im = ~retu_read_reg(RETU_REG_IMR);
+		id &= im;
+
+		if (!id)
+			break;
+
+		for (i = 0; id != 0; i++, id >>= 1) {
+			if (!(id & 1))
+				continue;
+			hnd = &retu_irq_handlers[i];
+			if (hnd->func == NULL) {
+                               /* Spurious retu interrupt - disable and ack it */
+				printk(KERN_INFO "Spurious Retu interrupt "
+						 "(id %d)\n", i);
+				retu_disable_irq(i);
+				retu_ack_irq(i);
+				continue;
+			}
+			hnd->func(hnd->arg);
+			/*
+			 * Don't acknowledge the interrupt here
+			 * It must be done explicitly
+			 */
+		}
+	}
+}
+
+/*
+ * Register the handler for a given RETU interrupt source.
+ */
+int retu_request_irq(int id, void *irq_handler, unsigned long arg, char *name)
+{
+	struct retu_irq_handler_desc *hnd;
+
+	if (irq_handler == NULL || id >= MAX_RETU_IRQ_HANDLERS ||
+	    name == NULL) {
+		printk(KERN_ERR PFX "Invalid arguments to %s\n",
+		       __FUNCTION__);
+		return -EINVAL;
+	}
+	hnd = &retu_irq_handlers[id];
+	if (hnd->func != NULL) {
+		printk(KERN_ERR PFX "IRQ %d already reserved\n", id);
+		return -EBUSY;
+	}
+	printk(KERN_INFO PFX "Registering interrupt %d for device %s\n",
+	       id, name);
+	hnd->func = irq_handler;
+	hnd->arg = arg;
+	strlcpy(hnd->name, name, sizeof(hnd->name));
+
+	retu_ack_irq(id);
+	retu_enable_irq(id);
+
+	return 0;
+}
+
+/*
+ * Unregister the handler for a given RETU interrupt source.
+ */
+void retu_free_irq(int id)
+{
+	struct retu_irq_handler_desc *hnd;
+
+	if (id >= MAX_RETU_IRQ_HANDLERS) {
+		printk(KERN_ERR PFX "Invalid argument to %s\n",
+		       __FUNCTION__);
+		return;
+	}
+	hnd = &retu_irq_handlers[id];
+	if (hnd->func == NULL) {
+		printk(KERN_ERR PFX "IRQ %d already freed\n", id);
+		return;
+	}
+
+	retu_disable_irq(id);
+	hnd->func = NULL;
+}
+
+/**
+ * retu_power_off - Shut down power to system
+ *
+ * This function puts the system in power off state
+ */
+static void retu_power_off(void)
+{
+	/* Ignore power button state */
+	retu_write_reg(RETU_REG_CC1, retu_read_reg(RETU_REG_CC1) | 2);
+	/* Expire watchdog immediately */
+	retu_write_reg(RETU_REG_WATCHDOG, 0);
+	/* Wait for poweroff*/
+	for (;;);
+}
+
+/**
+ * retu_probe - Probe for Retu ASIC
+ * @dev: the Retu device
+ *
+ * Probe for the Retu ASIC and allocate memory
+ * for its device-struct if found
+ */
+static int __devinit retu_probe(struct device *dev)
+{
+	const struct omap_em_asic_bb5_config * em_asic_config;
+	int rev, ret;
+
+	/* Prepare tasklet */
+	tasklet_init(&retu_tasklet, retu_tasklet_handler, 0);
+
+	em_asic_config = omap_get_config(OMAP_TAG_EM_ASIC_BB5,
+					 struct omap_em_asic_bb5_config);
+	if (em_asic_config == NULL) {
+		printk(KERN_ERR PFX "Unable to retrieve config data\n");
+		return -ENODATA;
+	}
+
+	retu_irq_pin = em_asic_config->retu_irq_gpio;
+
+	if ((ret = omap_request_gpio(retu_irq_pin)) < 0) {
+		printk(KERN_ERR PFX "Unable to reserve IRQ GPIO\n");
+		return ret;
+	}
+
+	/* Set the pin as input */
+	omap_set_gpio_direction(retu_irq_pin, 1);
+
+	/* Rising edge triggers the IRQ */
+	set_irq_type(OMAP_GPIO_IRQ(retu_irq_pin), IRQT_RISING);
+
+	retu_initialized = 1;
+
+	rev = retu_read_reg(RETU_REG_ASICR) & 0xff;
+	if (rev & (1 << 7))
+		retu_is_vilma = 1;
+
+	printk(KERN_INFO "%s v%d.%d found\n", retu_is_vilma ? "Vilma" : "Retu",
+	       (rev >> 4) & 0x07, rev & 0x0f);
+
+	/* Mask all RETU interrupts */
+	retu_write_reg(RETU_REG_IMR, 0xffff);
+
+	ret = request_irq(OMAP_GPIO_IRQ(retu_irq_pin), retu_irq_handler, 0,
+			  "retu", 0);
+	if (ret < 0) {
+		printk(KERN_ERR PFX "Unable to register IRQ handler\n");
+		omap_free_gpio(retu_irq_pin);
+		return ret;
+	}
+	set_irq_wake(OMAP_GPIO_IRQ(retu_irq_pin), 1);
+
+	/* Register power off function */
+	pm_power_off = retu_power_off;
+
+#ifdef CONFIG_CBUS_RETU_USER
+	/* Initialize user-space interface */
+	if (retu_user_init() < 0) {
+		printk(KERN_ERR "Unable to initialize driver\n");
+		free_irq(OMAP_GPIO_IRQ(retu_irq_pin), 0);
+		omap_free_gpio(retu_irq_pin);
+		return ret;
+	}
+#endif
+
+	return 0;
+}
+
+static int retu_remove(struct device *dev)
+{
+#ifdef CONFIG_CBUS_RETU_USER
+	retu_user_cleanup();
+#endif
+	/* Mask all RETU interrupts */
+	retu_write_reg(RETU_REG_IMR, 0xffff);
+	free_irq(OMAP_GPIO_IRQ(retu_irq_pin), 0);
+	omap_free_gpio(retu_irq_pin);
+	tasklet_kill(&retu_tasklet);
+
+	return 0;
+}
+
+static void retu_device_release(struct device *dev)
+{
+	complete(&device_release);
+}
+
+static struct device_driver retu_driver = {
+	.name		= "retu",
+	.bus		= &platform_bus_type,
+	.probe		= retu_probe,
+	.remove		= retu_remove,
+};
+
+static struct platform_device retu_device = {
+	.name		= "retu",
+	.id		= -1,
+	.dev = {
+		.release = retu_device_release,
+	}
+};
+
+/**
+ * retu_init - initialise Retu driver
+ *
+ * Initialise the Retu driver and return 0 if everything worked ok
+ */
+static int __init retu_init(void)
+{
+	int ret = 0;
+
+	printk(KERN_INFO "Retu/Vilma driver initialising\n");
+
+	init_completion(&device_release);
+
+	if ((ret = driver_register(&retu_driver)) < 0)
+		return ret;
+
+	if ((ret = platform_device_register(&retu_device)) < 0) {
+		driver_unregister(&retu_driver);
+		return ret;
+	}
+	return 0;
+}
+
+/*
+ * Cleanup
+ */
+static void __exit retu_exit(void)
+{
+	platform_device_unregister(&retu_device);
+	driver_unregister(&retu_driver);
+	wait_for_completion(&device_release);
+}
+
+EXPORT_SYMBOL(retu_request_irq);
+EXPORT_SYMBOL(retu_free_irq);
+EXPORT_SYMBOL(retu_enable_irq);
+EXPORT_SYMBOL(retu_disable_irq);
+EXPORT_SYMBOL(retu_ack_irq);
+EXPORT_SYMBOL(retu_read_reg);
+EXPORT_SYMBOL(retu_write_reg);
+
+subsys_initcall(retu_init);
+module_exit(retu_exit);
+
+MODULE_DESCRIPTION("Retu ASIC control");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Juha Yrjl, David Weinehall, and Mikko Ylinen");

drivers/cbus/retu.h

+/**
+ * drivers/cbus/retu.h
+ *
+ * Copyright (C) 2004, 2005 Nokia Corporation
+ *
+ * Written by Juha Yrjl <juha.yrjola@nokia.com> and
+ *	      David Weinehall <david.weinehall@nokia.com>
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file "COPYING" in the main directory of this
+ * archive for more details.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef __DRIVERS_CBUS_RETU_H
+#define __DRIVERS_CBUS_RETU_H
+
+#include <linux/types.h>
+
+/* Registers */
+#define RETU_REG_ASICR		0x00	/* ASIC ID & revision */
+#define RETU_REG_IDR		0x01	/* Interrupt ID */
+#define RETU_REG_IMR		0x02	/* Interrupt mask */
+#define RETU_REG_RTCDSR		0x03	/* RTC seconds register */
+#define RETU_REG_RTCHMR		0x04	/* RTC hours and minutes register */
+#define RETU_REG_RTCHMAR	0x05	/* RTC hours and minutes alarm and time set register */
+#define RETU_REG_RTCCALR	0x06	/* RTC calibration register */
+#define RETU_REG_ADCR		0x08	/* ADC result */
+#define RETU_REG_CC1		0x0d	/* Common control register 1 */
+#define RETU_REG_CC2		0x0e	/* Common control register 2 */
+#define RETU_REG_CTRL_CLR	0x0f	/* Regulator clear register */
+#define RETU_REG_CTRL_SET	0x10	/* Regulator set register */
+#define RETU_REG_STATUS		0x16	/* Status register */
+#define RETU_REG_WATCHDOG	0x17	/* Watchdog register */
+#define RETU_REG_AUDTXR		0x18	/* Audio Codec Tx register */
+#define RETU_REG_MAX		0x1f
+
+/* Interrupt sources */
+#define RETU_INT_PWR		0
+#define RETU_INT_CHAR		1
+#define RETU_INT_RTCS		2
+#define RETU_INT_RTCM		3
+#define RETU_INT_RTCD		4
+#define RETU_INT_RTCA		5
+#define RETU_INT_HOOK		6
+#define RETU_INT_HEAD		7
+#define RETU_INT_ADCS		8
+
+#define	MAX_RETU_IRQ_HANDLERS	16
+
+int retu_read_reg(int reg);
+void retu_write_reg(int reg, u16 val);
+void retu_set_clear_reg_bits(int reg, u16 set, u16 clear);
+int retu_read_adc(int channel);
+int retu_request_irq(int id, void *irq_handler, unsigned long arg, char *name);
+void retu_free_irq(int id);
+void retu_enable_irq(int id);
+void retu_disable_irq(int id);
+void retu_ack_irq(int id);
+
+#ifdef CONFIG_CBUS_RETU_USER
+int retu_user_init(void);
+void retu_user_cleanup(void);
+#endif
+
+extern spinlock_t retu_lock;
+
+#endif /* __DRIVERS_CBUS_RETU_H */

drivers/cbus/tahvo-usb.c

+/**
+ * drivers/cbus/tahvo-usb.c
+ *
+ * Tahvo USB transeiver
+ *
+ * Copyright (C) 2005-2006 Nokia Corporation
+ *
+ * Parts copied from drivers/i2c/chips/isp1301_omap.c
+ * Copyright (C) 2004 Texas Instruments
+ * Copyright (C) 2004 David Brownell
+ *
+ * Written by Juha Yrjl <juha.yrjola@nokia.com>,
+ *	      Tony Lindgren <tony@atomide.com>, and
+ *	      Timo Ters <timo.teras@nokia.com>
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file "COPYING" in the main directory of this
+ * archive for more details.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/usb/ch9.h>
+#include <linux/usb_gadget.h>
+#include <linux/usb.h>
+#include <linux/usb/otg.h>
+#include <linux/i2c.h>
+#include <linux/workqueue.h>
+#include <linux/kobject.h>
+#include <linux/clk.h>
+#include <linux/mutex.h>
+
+#include <asm/irq.h>
+#include <asm/arch/usb.h>
+
+#include "cbus.h"
+#include "tahvo.h"
+
+#define DRIVER_NAME     "tahvo-usb"
+
+#define USBR_SLAVE_CONTROL	(1 << 8)
+#define USBR_VPPVIO_SW		(1 << 7)
+#define USBR_SPEED		(1 << 6)
+#define USBR_REGOUT		(1 << 5)
+#define USBR_MASTER_SW2		(1 << 4)
+#define USBR_MASTER_SW1		(1 << 3)
+#define USBR_SLAVE_SW		(1 << 2)
+#define USBR_NSUSPEND		(1 << 1)
+#define USBR_SEMODE		(1 << 0)
+
+/* bits in OTG_CTRL_REG */
+
+/* Bits that are controlled by OMAP OTG and are read-only */
+#define OTG_CTRL_OMAP_MASK	(OTG_PULLDOWN|OTG_PULLUP|OTG_DRV_VBUS|\
+				OTG_PD_VBUS|OTG_PU_VBUS|OTG_PU_ID)
+/* Bits that are controlled by transceiver */
+#define OTG_CTRL_XCVR_MASK	(OTG_ASESSVLD|OTG_BSESSEND|\
+				OTG_BSESSVLD|OTG_VBUSVLD|OTG_ID)
+/* Bits that are controlled by system */
+#define OTG_CTRL_SYS_MASK	(OTG_A_BUSREQ|OTG_A_SETB_HNPEN|OTG_B_BUSREQ|\
+				OTG_B_HNPEN|OTG_BUSDROP)
+
+#if defined(CONFIG_USB_OHCI_HCD) && !defined(CONFIG_USB_OTG)
+#error tahvo-otg.c does not work with OCHI yet!
+#endif
+
+#define TAHVO_MODE_HOST		0
+#define TAHVO_MODE_PERIPHERAL	1
+
+#ifdef CONFIG_USB_OTG
+#define TAHVO_MODE(tu)		(tu)->tahvo_mode
+#elif defined(CONFIG_USB_GADGET_OMAP)
+#define TAHVO_MODE(tu)		TAHVO_MODE_PERIPHERAL
+#else
+#define TAHVO_MODE(tu)		TAHVO_MODE_HOST
+#endif
+
+struct tahvo_usb {
+	struct platform_device *pt_dev;
+	struct otg_transceiver otg;
+	int vbus_state;
+	struct work_struct irq_work;
+	struct mutex serialize;
+#ifdef CONFIG_USB_OTG
+	int tahvo_mode;
+#endif
+};
+static struct platform_device tahvo_usb_device;
+
+/*
+ * ---------------------------------------------------------------------------
+ * OTG related functions
+ *
+ * These shoud be separated into omap-otg.c driver module, as they are used
+ * by various transceivers. These functions are needed in the UDC-only case
+ * as well. These functions are copied from GPL isp1301_omap.c
+ * ---------------------------------------------------------------------------
+ */
+static struct platform_device *tahvo_otg_dev;
+
+static irqreturn_t omap_otg_irq(int irq, void *arg)
+{
+	struct platform_device *otg_dev = (struct platform_device *) arg;
+	struct tahvo_usb *tu = (struct tahvo_usb *) otg_dev->dev.driver_data;
+	u16 otg_irq;
+
+	otg_irq = OTG_IRQ_SRC_REG;
+	if (otg_irq & OPRT_CHG) {
+		OTG_IRQ_SRC_REG = OPRT_CHG;
+	} else if (otg_irq & B_SRP_TMROUT) {
+		OTG_IRQ_SRC_REG = B_SRP_TMROUT;
+	} else if (otg_irq & B_HNP_FAIL) {
+		OTG_IRQ_SRC_REG = B_HNP_FAIL;
+	} else if (otg_irq & A_SRP_DETECT) {
+		OTG_IRQ_SRC_REG = A_SRP_DETECT;
+	} else if (otg_irq & A_REQ_TMROUT) {
+		OTG_IRQ_SRC_REG = A_REQ_TMROUT;
+	} else if (otg_irq & A_VBUS_ERR) {
+		OTG_IRQ_SRC_REG = A_VBUS_ERR;
+	} else if (otg_irq & DRIVER_SWITCH) {
+		if ((!(OTG_CTRL_REG & OTG_DRIVER_SEL)) &&
+		   tu->otg.host && tu->otg.state == OTG_STATE_A_HOST) {
+			/* role is host */
+			usb_bus_start_enum(tu->otg.host,
+					   tu->otg.host->otg_port);
+		}
+		OTG_IRQ_SRC_REG = DRIVER_SWITCH;
+	} else
+		return IRQ_NONE;
+
+	return IRQ_HANDLED;
+
+}
+
+static int omap_otg_init(void)
+{
+
+#ifdef CONFIG_USB_OTG
+	if (!tahvo_otg_dev) {
+		printk("tahvo-usb: no tahvo_otg_dev\n");
+		return -ENODEV;
+	}
+#endif
+	OTG_SYSCON_1_REG &= ~OTG_IDLE_EN;
+	udelay(100);
+
+	/* some of these values are board-specific... */
+	OTG_SYSCON_2_REG |= OTG_EN
+		/* for B-device: */
+		| SRP_GPDATA		/* 9msec Bdev D+ pulse */
+		| SRP_GPDVBUS		/* discharge after VBUS pulse */
+		// | (3 << 24)		/* 2msec VBUS pulse */
+		/* for A-device: */
+		| (0 << 20)		/* 200ms nominal A_WAIT_VRISE timer */
+		| SRP_DPW		/* detect 167+ns SRP pulses */
+		| SRP_DATA | SRP_VBUS;	/* accept both kinds of SRP pulse */
+
+	OTG_IRQ_EN_REG = DRIVER_SWITCH | OPRT_CHG
+			| B_SRP_TMROUT | B_HNP_FAIL
+			| A_VBUS_ERR | A_SRP_DETECT | A_REQ_TMROUT;
+	OTG_SYSCON_2_REG |= OTG_EN;
+
+	return 0;
+}
+
+static int omap_otg_probe(struct device *dev)
+{
+	int ret;
+
+	tahvo_otg_dev = to_platform_device(dev);
+	ret = omap_otg_init();
+	if (ret != 0) {
+		printk(KERN_ERR "tahvo-usb: omap_otg_init failed\n");
+		return ret;
+	}
+
+	return request_irq(tahvo_otg_dev->resource[1].start,
+			   omap_otg_irq, IRQF_DISABLED, DRIVER_NAME,
+			   &tahvo_usb_device);
+}
+
+static int omap_otg_remove(struct device *dev)
+{
+	free_irq(tahvo_otg_dev->resource[1].start, &tahvo_usb_device);
+	tahvo_otg_dev = NULL;
+
+	return 0;
+}
+
+struct device_driver omap_otg_driver = {
+	.name		= "omap_otg",
+	.bus		= &platform_bus_type,
+	.probe		= omap_otg_probe,
+	.remove		= omap_otg_remove,
+};
+
+/*
+ * ---------------------------------------------------------------------------
+ * Tahvo related functions
+ * These are Nokia proprietary code, except for the OTG register settings,
+ * which are copied from isp1301.c
+ * ---------------------------------------------------------------------------
+ */
+static ssize_t vbus_state_show(struct device *device,
+			       struct device_attribute *attr, char *buf)
+{
+	struct tahvo_usb *tu = (struct tahvo_usb*) device->driver_data;
+	return sprintf(buf, "%d\n", tu->vbus_state);
+}
+static DEVICE_ATTR(vbus_state, 0444, vbus_state_show, NULL);
+
+int vbus_active = 0;
+
+#if 0
+
+static int host_suspend(struct tahvo_usb *tu)
+{
+	struct device	*dev;
+
+	if (!tu->otg.host)
+		return -ENODEV;
+
+	/* Currently ASSUMES only the OTG port matters;
+	 * other ports could be active...
+	 */
+	dev = tu->otg.host->controller;
+	return dev->driver->suspend(dev, PMSG_SUSPEND);
+}
+
+static int host_resume(struct tahvo_usb *tu)
+{
+	struct device	*dev;
+
+	if (!tu->otg.host)
+		return -ENODEV;
+
+	dev = tu->otg.host->controller;
+	return dev->driver->resume(dev);
+}
+
+#else
+
+static int host_suspend(struct tahvo_usb *tu)
+{
+	return 0;
+}
+
+static int host_resume(struct tahvo_usb *tu)
+{
+	return 0;
+}
+
+#endif
+
+static void check_vbus_state(struct tahvo_usb *tu)
+{
+	int reg, prev_state;
+
+	reg = tahvo_read_reg(TAHVO_REG_IDSR);
+	if (reg & 0x01) {
+		vbus_active = 1;
+		switch (tu->otg.state) {
+		case OTG_STATE_B_IDLE:
+			/* Enable the gadget driver */
+			if (tu->otg.gadget)
+				usb_gadget_vbus_connect(tu->otg.gadget);
+			/* Set B-session valid and not B-sessio ended to indicate
+			 * Vbus to be ok. */
+			OTG_CTRL_REG = (OTG_CTRL_REG & ~OTG_BSESSEND) | OTG_BSESSVLD;
+
+			tu->otg.state = OTG_STATE_B_PERIPHERAL;
+			break;
+		case OTG_STATE_A_IDLE:
+			/* Session is now valid assuming the USB hub is driving Vbus */
+			tu->otg.state = OTG_STATE_A_HOST;
+			host_resume(tu);
+			break;
+		default:
+			break;
+		}
+		printk("USB cable connected\n");
+	} else {
+		switch (tu->otg.state) {
+		case OTG_STATE_B_PERIPHERAL:
+			if (tu->otg.gadget)
+				usb_gadget_vbus_disconnect(tu->otg.gadget);
+			tu->otg.state = OTG_STATE_B_IDLE;
+			break;
+		case OTG_STATE_A_HOST:
+			tu->otg.state = OTG_STATE_A_IDLE;
+			break;
+		default:
+			break;
+		}
+		printk("USB cable disconnected\n");
+		vbus_active = 0;
+	}
+
+	prev_state = tu->vbus_state;
+	tu->vbus_state = reg & 0x01;
+	if (prev_state != tu->vbus_state)
+		sysfs_notify(&tu->pt_dev->dev.kobj, NULL, "vbus_state");
+}
+
+static void tahvo_usb_become_host(struct tahvo_usb *tu)
+{
+	u32 l;
+
+	/* Clear system and transceiver controlled bits
+	 * also mark the A-session is always valid */
+	omap_otg_init();
+
+	l = OTG_CTRL_REG;
+	l &= ~(OTG_CTRL_XCVR_MASK|OTG_CTRL_SYS_MASK);
+	l |= OTG_ASESSVLD;
+	OTG_CTRL_REG = l;
+
+	/* Power up the transceiver in USB host mode */
+	tahvo_write_reg(TAHVO_REG_USBR, USBR_REGOUT | USBR_NSUSPEND |
+			USBR_MASTER_SW2 | USBR_MASTER_SW1);
+	tu->otg.state = OTG_STATE_A_IDLE;
+
+	check_vbus_state(tu);
+}
+
+static void tahvo_usb_stop_host(struct tahvo_usb *tu)
+{
+	host_suspend(tu);
+	tu->otg.state = OTG_STATE_A_IDLE;
+}
+
+static void tahvo_usb_become_peripheral(struct tahvo_usb *tu)
+{
+	/* Clear system and transceiver controlled bits
+	 * and enable ID to mark peripheral mode and
+	 * BSESSEND to mark no Vbus */
+	omap_otg_init();
+	OTG_CTRL_REG = (OTG_CTRL_REG & ~(OTG_CTRL_XCVR_MASK|OTG_CTRL_SYS_MASK|OTG_BSESSVLD))
+		| OTG_ID | OTG_BSESSEND;
+
+	/* Power up transceiver and set it in USB perhiperal mode */
+	tahvo_write_reg(TAHVO_REG_USBR, USBR_SLAVE_CONTROL | USBR_REGOUT | USBR_NSUSPEND | USBR_SLAVE_SW);
+	tu->otg.state = OTG_STATE_B_IDLE;
+
+	check_vbus_state(tu);
+}
+
+static void tahvo_usb_stop_peripheral(struct tahvo_usb *tu)
+{
+	OTG_CTRL_REG = (OTG_CTRL_REG & ~OTG_BSESSVLD) | OTG_BSESSEND;
+	if (tu->otg.gadget)
+		usb_gadget_vbus_disconnect(tu->otg.gadget);
+	tu->otg.state = OTG_STATE_B_IDLE;
+
+}
+
+static void tahvo_usb_power_off(struct tahvo_usb *tu)
+{
+	u32 l;
+	int id;
+
+	/* Disable gadget controller if any */
+	if (tu->otg.gadget)
+		usb_gadget_vbus_disconnect(tu->otg.gadget);
+
+	host_suspend(tu);
+
+	/* Disable OTG and interrupts */
+	if (TAHVO_MODE(tu) == TAHVO_MODE_PERIPHERAL)
+		id = OTG_ID;
+	else
+		id = 0;
+	l = OTG_CTRL_REG;
+	l &= ~(OTG_CTRL_XCVR_MASK | OTG_CTRL_SYS_MASK | OTG_BSESSVLD);
+	l |= id | OTG_BSESSEND;
+	OTG_CTRL_REG = l;
+	OTG_IRQ_EN_REG = 0;
+
+	OTG_SYSCON_2_REG &= ~OTG_EN;
+
+	OTG_SYSCON_1_REG |= OTG_IDLE_EN;
+
+	/* Power off transceiver */
+	tahvo_write_reg(TAHVO_REG_USBR, 0);
+	tu->otg.state = OTG_STATE_UNDEFINED;
+}
+
+
+static int tahvo_usb_set_power(struct otg_transceiver *dev, unsigned mA)
+{
+	struct tahvo_usb *tu = container_of(dev, struct tahvo_usb, otg);
+
+	dev_dbg(&tu->pt_dev->dev, "set_power %d mA\n", mA);
+
+	if (dev->state == OTG_STATE_B_PERIPHERAL) {
+		/* REVISIT: Can Tahvo charge battery from VBUS? */
+	}
+	return 0;
+}
+
+static int tahvo_usb_set_suspend(struct otg_transceiver *dev, int suspend)
+{
+	struct tahvo_usb *tu = container_of(dev, struct tahvo_usb, otg);
+	u16 w;
+
+	dev_dbg(&tu->pt_dev->dev, "set_suspend\n");
+
+	w = tahvo_read_reg(TAHVO_REG_USBR);
+	if (suspend)
+		w &= ~USBR_NSUSPEND;
+	else
+		w |= USBR_NSUSPEND;
+	tahvo_write_reg(TAHVO_REG_USBR, w);
+
+	return 0;
+}
+
+static int tahvo_usb_start_srp(struct otg_transceiver *dev)
+{
+	struct tahvo_usb *tu = container_of(dev, struct tahvo_usb, otg);
+	u32 otg_ctrl;
+
+	dev_dbg(&tu->pt_dev->dev, "start_srp\n");
+
+	if (!dev || tu->otg.state != OTG_STATE_B_IDLE)
+		return -ENODEV;
+
+	otg_ctrl = OTG_CTRL_REG;
+	if (!(otg_ctrl & OTG_BSESSEND))
+		return -EINVAL;
+
+	otg_ctrl |= OTG_B_BUSREQ;
+	otg_ctrl &= ~OTG_A_BUSREQ & OTG_CTRL_SYS_MASK;
+	OTG_CTRL_REG = otg_ctrl;
+	tu->otg.state = OTG_STATE_B_SRP_INIT;
+
+	return 0;
+}
+
+static int tahvo_usb_start_hnp(struct otg_transceiver *otg)
+{
+	struct tahvo_usb *tu = container_of(otg, struct tahvo_usb, otg);
+
+	dev_dbg(&tu->pt_dev->dev, "start_hnp\n");
+#ifdef CONFIG_USB_OTG
+	/* REVISIT: Add this for OTG */
+#endif
+	return -EINVAL;
+}
+
+static int tahvo_usb_set_host(struct otg_transceiver *otg, struct usb_bus *host)
+{
+	struct tahvo_usb *tu = container_of(otg, struct tahvo_usb, otg);
+
+	dev_dbg(&tu->pt_dev->dev, "set_host %p\n", host);
+
+	if (otg == NULL)
+		return -ENODEV;
+
+#if defined(CONFIG_USB_OTG) || !defined(CONFIG_USB_GADGET_OMAP)
+
+	mutex_lock(&tu->serialize);
+
+	if (host == NULL) {
+		if (TAHVO_MODE(tu) == TAHVO_MODE_HOST)
+			tahvo_usb_power_off(tu);
+		tu->otg.host = NULL;
+		mutex_unlock(&tu->serialize);
+		return 0;
+	}
+
+	OTG_SYSCON_1_REG &= ~(OTG_IDLE_EN | HST_IDLE_EN | DEV_IDLE_EN);
+
+	if (TAHVO_MODE(tu) == TAHVO_MODE_HOST) {
+		tu->otg.host = NULL;
+		tahvo_usb_become_host(tu);
+	} else
+		host_suspend(tu);
+
+	tu->otg.host = host;
+
+	mutex_unlock(&tu->serialize);
+#else
+	/* No host mode configured, so do not allow host controlled to be set */
+	return -EINVAL;
+#endif
+
+	return 0;
+}
+
+static int tahvo_usb_set_peripheral(struct otg_transceiver *otg, struct usb_gadget *gadget)
+{
+	struct tahvo_usb *tu = container_of(otg, struct tahvo_usb, otg);
+
+	dev_dbg(&tu->pt_dev->dev, "set_peripheral %p\n", gadget);
+
+	if (!otg)
+		return -ENODEV;
+
+#if defined(CONFIG_USB_OTG) || defined(CONFIG_USB_GADGET_OMAP)
+
+	mutex_lock(&tu->serialize);
+
+	if (!gadget) {
+		if (TAHVO_MODE(tu) == TAHVO_MODE_PERIPHERAL)
+			tahvo_usb_power_off(tu);
+		tu->otg.gadget = NULL;
+		mutex_unlock(&tu->serialize);
+		return 0;
+	}
+
+	tu->otg.gadget = gadget;
+	if (TAHVO_MODE(tu) == TAHVO_MODE_PERIPHERAL)
+		tahvo_usb_become_peripheral(tu);
+
+	mutex_unlock(&tu->serialize);
+#else
+	/* No gadget mode configured, so do not allow host controlled to be set */
+	return -EINVAL;
+#endif
+
+	return 0;
+}
+
+static void tahvo_usb_irq_work(struct work_struct *work)
+{
+	struct tahvo_usb *tu = container_of(work, struct tahvo_usb, irq_work);
+
+	mutex_lock(&tu->serialize);
+	check_vbus_state(tu);
+	mutex_unlock(&tu->serialize);
+}
+
+static void tahvo_usb_vbus_interrupt(unsigned long arg)
+{
+	struct tahvo_usb *tu = (struct tahvo_usb *) arg;
+
+	tahvo_ack_irq(TAHVO_INT_VBUSON);
+	/* Seems we need this to acknowledge the interrupt */
+	tahvo_read_reg(TAHVO_REG_IDSR);
+	schedule_work(&tu->irq_work);
+}
+
+#ifdef CONFIG_USB_OTG
+static ssize_t otg_mode_show(struct device *device,
+			     struct device_attribute *attr, char *buf)
+{
+	struct tahvo_usb *tu = (struct tahvo_usb*) device->driver_data;
+	switch (tu->tahvo_mode) {
+	case TAHVO_MODE_HOST:
+		return sprintf(buf, "host\n");
+	case TAHVO_MODE_PERIPHERAL:
+		return sprintf(buf, "peripheral\n");
+	}
+	return sprintf(buf, "unknown\n");
+}
+
+static ssize_t otg_mode_store(struct device *device,
+			      struct device_attribute *attr,
+			      const char *buf, size_t count)
+{
+	struct tahvo_usb *tu = (struct tahvo_usb*) device->driver_data;
+	int r;
+
+	r = strlen(buf);
+	mutex_lock(&tu->serialize);
+	if (strncmp(buf, "host", 4) == 0) {
+		if (tu->tahvo_mode == TAHVO_MODE_PERIPHERAL)
+			tahvo_usb_stop_peripheral(tu);
+		tu->tahvo_mode = TAHVO_MODE_HOST;
+		if (tu->otg.host) {
+			printk(KERN_INFO "Selected HOST mode: host controller present.\n");
+			tahvo_usb_become_host(tu);
+		} else {
+			printk(KERN_INFO "Selected HOST mode: no host controller, powering off.\n");
+			tahvo_usb_power_off(tu);
+		}
+	} else if (strncmp(buf, "peripheral", 10) == 0) {
+		if (tu->tahvo_mode == TAHVO_MODE_HOST)
+			tahvo_usb_stop_host(tu);
+		tu->tahvo_mode = TAHVO_MODE_PERIPHERAL;
+		if (tu->otg.gadget) {
+			printk(KERN_INFO "Selected PERIPHERAL mode: gadget driver present.\n");
+			tahvo_usb_become_peripheral(tu);
+		} else {
+			printk(KERN_INFO "Selected PERIPHERAL mode: no gadget driver, powering off.\n");
+			tahvo_usb_power_off(tu);
+		}
+	} else
+		r = -EINVAL;
+
+	mutex_unlock(&tu->serialize);
+	return r;
+}
+
+static DEVICE_ATTR(otg_mode, 0644, otg_mode_show, otg_mode_store);
+#endif
+
+static int tahvo_usb_probe(struct device *dev)
+{
+	struct tahvo_usb *tu;
+	int ret;
+
+	dev_dbg(dev, "probe\n");
+
+	/* Create driver data */
+	tu = kmalloc(sizeof(*tu), GFP_KERNEL);
+	if (!tu)
+		return -ENOMEM;
+	memset(tu, 0, sizeof(*tu));
+	tu->pt_dev = container_of(dev, struct platform_device, dev);
+#ifdef CONFIG_USB_OTG
+	/* Default mode */
+#ifdef CONFIG_CBUS_TAHVO_USB_HOST_BY_DEFAULT
+	tu->tahvo_mode = TAHVO_MODE_HOST;
+#else
+	tu->tahvo_mode = TAHVO_MODE_PERIPHERAL;
+#endif
+#endif
+
+	INIT_WORK(&tu->irq_work, tahvo_usb_irq_work);
+	mutex_init(&tu->serialize);
+
+	/* Set initial state, so that we generate kevents only on
+	 * state changes */
+	tu->vbus_state = tahvo_read_reg(TAHVO_REG_IDSR) & 0x01;
+
+	/* We cannot enable interrupt until omap_udc is initialized */
+	ret = tahvo_request_irq(TAHVO_INT_VBUSON, tahvo_usb_vbus_interrupt,
+				(unsigned long) tu, "vbus_interrupt");
+	if (ret != 0) {
+		kfree(tu);
+		printk(KERN_ERR "Could not register Tahvo interrupt for VBUS\n");
+		return ret;
+	}
+
+	/* Attributes */
+	ret = device_create_file(dev, &dev_attr_vbus_state);
+#ifdef CONFIG_USB_OTG
+	ret |= device_create_file(dev, &dev_attr_otg_mode);
+#endif
+	if (ret)
+		printk(KERN_ERR "attribute creation failed: %d\n", ret);
+
+	/* Create OTG interface */
+	tahvo_usb_power_off(tu);
+	tu->otg.state = OTG_STATE_UNDEFINED;
+	tu->otg.label = DRIVER_NAME;
+	tu->otg.set_host = tahvo_usb_set_host;
+	tu->otg.set_peripheral = tahvo_usb_set_peripheral;
+	tu->otg.set_power = tahvo_usb_set_power;
+	tu->otg.set_suspend = tahvo_usb_set_suspend;
+	tu->otg.start_srp = tahvo_usb_start_srp;
+	tu->otg.start_hnp = tahvo_usb_start_hnp;
+
+	ret = otg_set_transceiver(&tu->otg);
+	if (ret < 0) {
+		printk(KERN_ERR "Cannot register USB transceiver\n");
+		kfree(tu);
+		tahvo_free_irq(TAHVO_INT_VBUSON);
+		return ret;
+	}
+
+	dev->driver_data = tu;
+
+	/* Act upon current vbus state once at startup. A vbus state irq may or
+	 * may not be generated in addition to this. */
+	schedule_work(&tu->irq_work);
+	return 0;
+}
+
+static int tahvo_usb_remove(struct device *dev)
+{
+	dev_dbg(dev, "remove\n");
+
+	tahvo_free_irq(TAHVO_INT_VBUSON);
+	flush_scheduled_work();
+	otg_set_transceiver(0);
+	device_remove_file(dev, &dev_attr_vbus_state);
+#ifdef CONFIG_USB_OTG
+	device_remove_file(dev, &dev_attr_otg_mode);
+#endif
+	return 0;
+}
+
+static struct device_driver tahvo_usb_driver = {
+	.name		= "tahvo-usb",
+	.bus		= &platform_bus_type,
+	.probe		= tahvo_usb_probe,
+	.remove		= tahvo_usb_remove,
+};
+
+static struct platform_device tahvo_usb_device = {
+	.name		= "tahvo-usb",
+	.id		= -1,
+};
+
+static int __init tahvo_usb_init(void)
+{
+	int ret = 0;
+
+	printk(KERN_INFO "Tahvo USB transceiver driver initializing\n");
+	ret = driver_register(&tahvo_usb_driver);
+	if (ret)
+		return ret;
+	ret = platform_device_register(&tahvo_usb_device);
+	if (ret < 0) {
+		driver_unregister(&tahvo_usb_driver);
+		return ret;
+	}
+	ret = driver_register(&omap_otg_driver);
+	if (ret) {
+		platform_device_unregister(&tahvo_usb_device);
+		driver_unregister(&tahvo_usb_driver);
+		return ret;
+	}
+	return 0;
+}
+
+subsys_initcall(tahvo_usb_init);
+
+static void __exit tahvo_usb_exit(void)
+{
+	driver_unregister(&omap_otg_driver);
+	platform_device_unregister(&tahvo_usb_device);
+	driver_unregister(&tahvo_usb_driver);
+}
+module_exit(tahvo_usb_exit);
+
+MODULE_DESCRIPTION("Tahvo USB OTG Transceiver Driver");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Juha Yrjl, Tony Lindgren, and Timo Ters");

drivers/cbus/tahvo-user.c

+/**
+ * drivers/cbus/tahvo-user.c
+ *
+ * Tahvo user space interface functions
+ *
+ * Copyright (C) 2004, 2005 Nokia Corporation
+ *
+ * Written by Mikko Ylinen <mikko.k.ylinen@nokia.com>
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file "COPYING" in the main directory of this
+ * archive for more details.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>
+#include <linux/poll.h>
+#include <linux/list.h>
+#include <linux/spinlock.h>
+#include <linux/mutex.h>
+
+#include <asm/uaccess.h>
+
+#include "tahvo.h"
+
+#include "user_retu_tahvo.h"
+
+/* Maximum size of IRQ node buffer/pool */
+#define TAHVO_MAX_IRQ_BUF_LEN	16
+
+#define PFX			"tahvo-user: "
+
+/* Bitmap for marking the interrupt sources as having the handlers */
+static u32 tahvo_irq_bits;
+
+/* For allowing only one user process to subscribe to the tahvo interrupts */
+static struct file *tahvo_irq_subscr = NULL;
+
+/* For poll and IRQ passing */
+struct tahvo_irq {
+	u32 id;
+	struct list_head node;
+};
+
+static spinlock_t tahvo_irqs_lock;
+static struct tahvo_irq *tahvo_irq_block;
+static LIST_HEAD(tahvo_irqs);
+static LIST_HEAD(tahvo_irqs_reserve);
+
+/* Wait queue - used when user wants to read the device */
+DECLARE_WAIT_QUEUE_HEAD(tahvo_user_waitqueue);
+
+/* Semaphore to protect irq subscription sequence */
+static struct mutex tahvo_mutex;
+
+/* This array specifies TAHVO register types (read/write/toggle) */
+static const u8 tahvo_access_bits[] = {
+	1,
+	4,
+	1,
+	3,
+	3,
+	3,
+	3,
+	3,
+	3,
+	3,
+	3,
+	3,
+	3,
+	1
+};
+
+/*
+ * The handler for all TAHVO interrupts.
+ *
+ * arg is the interrupt source in TAHVO.
+ */
+static void tahvo_user_irq_handler(unsigned long arg)
+{
+	struct tahvo_irq *irq;
+
+	/* user has to re-enable the interrupt once ready
+	 * for receiving them again */
+	tahvo_disable_irq(arg);
+	tahvo_ack_irq(arg);
+
+	spin_lock(&tahvo_irqs_lock);
+	if (list_empty(&tahvo_irqs_reserve)) {
+		spin_unlock(&tahvo_irqs_lock);
+		return;
+	}
+	irq = list_entry((&tahvo_irqs_reserve)->next, struct tahvo_irq, node);
+	irq->id = arg;
+	list_move_tail(&irq->node, &tahvo_irqs);
+	spin_unlock(&tahvo_irqs_lock);
+
+	/* wake up waiting thread */
+	wake_up(&tahvo_user_waitqueue);
+}
+
+/*
+ * This routine sets up the interrupt handler and marks an interrupt source
+ * in TAHVO as a candidate for signal delivery to the user process.
+ */
+static int tahvo_user_subscribe_to_irq(int id, struct file *filp)
+{
+	int ret;
+
+	mutex_lock(&tahvo_mutex);
+	if ((tahvo_irq_subscr != NULL) && (tahvo_irq_subscr != filp)) {
+		mutex_unlock(&tahvo_mutex);
+		return -EBUSY;
+	}
+	/* Store the file pointer of the first user process registering IRQs */
+	tahvo_irq_subscr = filp;
+	mutex_unlock(&tahvo_mutex);
+
+	if (tahvo_irq_bits & (1 << id))
+		return 0;
+
+	ret = tahvo_request_irq(id, tahvo_user_irq_handler, id, "");
+	if (ret < 0)
+		return ret;
+
+	/* Mark that this interrupt has a handler */
+	tahvo_irq_bits |= 1 << id;
+
+	return 0;
+}
+
+/*
+ * Unregister all TAHVO interrupt handlers
+ */
+static void tahvo_unreg_irq_handlers(void)
+{
+	int id;
+
+	if (!tahvo_irq_bits)
+		return;
+
+	for (id = 0; id < MAX_TAHVO_IRQ_HANDLERS; id++)
+		if (tahvo_irq_bits & (1 << id))
+			tahvo_free_irq(id);
+
+	tahvo_irq_bits = 0;
+}
+
+/*
+ * Write to TAHVO register.
+ * Returns 0 upon success, a negative error value otherwise.
+ */
+static int tahvo_user_write_with_mask(u32 field, u16 value)
+{
+	u32 mask;
+	u32 reg;
+	u_short tmp;
+	unsigned long flags;
+
+	mask = MASK(field);
+	reg = REG(field);
+
+	/* Detect bad mask and reg */
+	if (mask == 0 || reg > TAHVO_REG_MAX ||
+	    tahvo_access_bits[reg] == READ_ONLY) {
+		printk(KERN_ERR PFX "invalid arguments (reg=%#x, mask=%#x)\n",
+		       reg, mask);
+		return -EINVAL;
+	}
+
+	/* Justify value according to mask */
+	while (!(mask & 1)) {
+		value = value << 1;
+		mask = mask >> 1;
+	}
+
+	spin_lock_irqsave(&tahvo_lock, flags);
+	if (tahvo_access_bits[reg] == TOGGLE) {
+		/* No need to detect previous content of register */
+		tmp = 0;
+	} else {
+		/* Read current value of register */
+		tmp = tahvo_read_reg(reg);
+	}
+	/* Generate a new value */
+	tmp = (tmp & ~MASK(field)) | (value & MASK(field));
+	/* Write data to TAHVO */
+	tahvo_write_reg(reg, tmp);
+	spin_unlock_irqrestore(&tahvo_lock, flags);
+
+	return 0;
+}
+
+/*
+ * Read TAHVO register.
+ */
+static u32 tahvo_user_read_with_mask(u32 field)
+{
+	u_short value;
+	u32 mask, reg;
+
+	mask = MASK(field);
+	reg = REG(field);
+
+	/* Detect bad mask and reg */
+	if (mask == 0 || reg > TAHVO_REG_MAX) {
+		printk(KERN_ERR PFX "invalid arguments (reg=%#x, mask=%#x)\n",
+		       reg, mask);
+		return -EINVAL;
+	}
+
+	/* Read the register */
+	value = tahvo_read_reg(reg) & mask;
+
+	/* Right justify value */
+	while (!(mask & 1)) {
+		value = value >> 1;
+		mask = mask >> 1;
+	}
+
+	return value;
+}
+
+/*
+ * Close device
+ */
+static int tahvo_close(struct inode *inode, struct file *filp)
+{
+	/* Unregister all interrupts that have been registered */
+	if (tahvo_irq_subscr == filp) {
+		tahvo_unreg_irq_handlers();
+		tahvo_irq_subscr = NULL;
+	}
+
+	return 0;
+}
+
+/*
+ * Device control (ioctl)
+ */
+static int tahvo_ioctl(struct inode *inode, struct file *filp,
+		       unsigned int cmd, unsigned long arg)
+{
+	struct retu_tahvo_write_parms par;
+	int ret;
+
+	switch (cmd) {
+	case URT_IOCT_IRQ_SUBSCR:
+		return tahvo_user_subscribe_to_irq(arg, filp);
+	case TAHVO_IOCH_READ:
+		return tahvo_user_read_with_mask(arg);
+	case TAHVO_IOCX_WRITE:
+		ret = copy_from_user(&par, (void __user *) arg, sizeof(par));
+		if (ret)
+			printk(KERN_ERR "copy_from_user failed: %d\n", ret);
+		par.result = tahvo_user_write_with_mask(par.field, par.value);
+		ret = copy_to_user((void __user *) arg, &par, sizeof(par));
+		if (ret)
+			printk(KERN_ERR "copy_to_user failed: %d\n", ret);
+		break;
+	default:
+		return -ENOIOCTLCMD;
+	}
+	return 0;
+}
+
+/*
+ * Read from device
+ */
+static ssize_t tahvo_read(struct file *filp, char *buf, size_t count,
+			  loff_t * offp)
+{
+	struct tahvo_irq *irq;
+
+	u32 nr, i;
+
+	/* read not permitted if neither filp nor anyone has registered IRQs */
+	if (tahvo_irq_subscr != filp)
+		return -EPERM;
+
+	if ((count < sizeof(u32)) || ((count % sizeof(u32)) != 0))
+		return -EINVAL;
+
+	nr = count / sizeof(u32);
+
+	for (i = 0; i < nr; i++) {
+		unsigned long flags;
+		u32 irq_id;
+		int ret;
+
+		ret = wait_event_interruptible(tahvo_user_waitqueue,
+					       !list_empty(&tahvo_irqs));
+		if (ret < 0)
+			return ret;
+
+		spin_lock_irqsave(&tahvo_irqs_lock, flags);
+		irq = list_entry((&tahvo_irqs)->next, struct tahvo_irq, node);
+		irq_id = irq->id;
+		list_move(&irq->node, &tahvo_irqs_reserve);
+		spin_unlock_irqrestore(&tahvo_irqs_lock, flags);
+
+		ret = copy_to_user(buf + i * sizeof(irq_id), &irq_id,
+                                  sizeof(irq_id));
+		if (ret)
+			printk(KERN_ERR "copy_to_user failed: %d\n", ret);
+	}
+
+	return count;
+}
+
+/*
+ * Poll method
+ */
+static unsigned tahvo_poll(struct file *filp, struct poll_table_struct *pt)
+{
+	if (!list_empty(&tahvo_irqs))
+		return POLLIN;
+
+	poll_wait(filp, &tahvo_user_waitqueue, pt);
+
+	if (!list_empty(&tahvo_irqs))
+		return POLLIN;
+	else
+		return 0;
+}
+
+static struct file_operations tahvo_user_fileops = {
+	.owner = THIS_MODULE,
+	.ioctl = tahvo_ioctl,
+	.read = tahvo_read,
+	.release = tahvo_close,
+	.poll = tahvo_poll
+};
+
+static struct miscdevice tahvo_device = {
+	.minor = MISC_DYNAMIC_MINOR,
+	.name = "tahvo",
+	.fops = &tahvo_user_fileops
+};
+
+/*
+ * Initialization
+ *
+ * @return 0 if successful, error value otherwise.
+ */
+int tahvo_user_init(void)
+{
+	struct tahvo_irq *irq;
+	int res, i;
+
+	irq = kmalloc(sizeof(*irq) * TAHVO_MAX_IRQ_BUF_LEN, GFP_KERNEL);
+	if (irq == NULL) {
+		printk(KERN_ERR PFX "kmalloc failed\n");
+		return -ENOMEM;
+	}
+	memset(irq, 0, sizeof(*irq) * TAHVO_MAX_IRQ_BUF_LEN);
+	for (i = 0; i < TAHVO_MAX_IRQ_BUF_LEN; i++)
+		list_add(&irq[i].node, &tahvo_irqs_reserve);
+
+	tahvo_irq_block = irq;
+
+	spin_lock_init(&tahvo_irqs_lock);
+	mutex_init(&tahvo_mutex);
+
+	/* Request a misc device */
+	res = misc_register(&tahvo_device);
+	if (res < 0) {
+		printk(KERN_ERR PFX "unable to register misc device for %s\n",
+		       tahvo_device.name);
+		kfree(irq);
+		return res;
+	}
+
+	return 0;
+}
+
+/*
+ * Cleanup.
+ */
+void tahvo_user_cleanup(void)
+{
+	/* Unregister our misc device */
+	misc_deregister(&tahvo_device);
+	/* Unregister and disable all TAHVO interrupts */
+	tahvo_unreg_irq_handlers();
+	kfree(tahvo_irq_block);
+}
+
+MODULE_DESCRIPTION("Tahvo ASIC user space functions");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Mikko Ylinen");

drivers/cbus/tahvo.c

+/**
+ * drivers/cbus/tahvo.c
+ *
+ * Support functions for Tahvo ASIC
+ *
+ * Copyright (C) 2004, 2005 Nokia Corporation
+ *
+ * Written by Juha Yrjl <juha.yrjola@nokia.com>,
+ *	      David Weinehall <david.weinehall@nokia.com>, and
+ *	      Mikko Ylinen <mikko.k.ylinen@nokia.com>
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file "COPYING" in the main directory of this
+ * archive for more details.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/device.h>
+#include <linux/miscdevice.h>
+#include <linux/poll.h>
+#include <linux/fs.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+
+#include <asm/uaccess.h>
+
+#include <asm/arch/mux.h>
+#include <asm/arch/gpio.h>
+#include <asm/arch/board.h>
+
+#include "cbus.h"
+#include "tahvo.h"
+
+#define TAHVO_ID		0x02
+#define PFX			"tahvo: "
+
+static int tahvo_initialized;
+static int tahvo_irq_pin;
+static int tahvo_is_betty;
+
+static struct tasklet_struct tahvo_tasklet;
+spinlock_t tahvo_lock = SPIN_LOCK_UNLOCKED;
+
+static struct completion device_release;
+
+struct tahvo_irq_handler_desc {
+	int (*func)(unsigned long);
+	unsigned long arg;
+	char name[8];
+};
+
+static struct tahvo_irq_handler_desc tahvo_irq_handlers[MAX_TAHVO_IRQ_HANDLERS];
+
+/**
+ * tahvo_read_reg - Read a value from a register in Tahvo
+ * @reg: the register to read from
+ *
+ * This function returns the contents of the specified register
+ */
+int tahvo_read_reg(int reg)
+{
+	BUG_ON(!tahvo_initialized);
+	return cbus_read_reg(cbus_host, TAHVO_ID, reg);
+}
+
+/**
+ * tahvo_write_reg - Write a value to a register in Tahvo
+ * @reg: the register to write to
+ * @reg: the value to write to the register
+ *
+ * This function writes a value to the specified register
+ */
+void tahvo_write_reg(int reg, u16 val)
+{
+	BUG_ON(!tahvo_initialized);
+	cbus_write_reg(cbus_host, TAHVO_ID, reg, val);
+}
+
+/**
+ * tahvo_set_clear_reg_bits - set and clear register bits atomically
+ * @reg: the register to write to
+ * @bits: the bits to set
+ *
+ * This function sets and clears the specified Tahvo register bits atomically
+ */
+void tahvo_set_clear_reg_bits(int reg, u16 set, u16 clear)
+{
+	unsigned long flags;
+	u16 w;
+
+	spin_lock_irqsave(&tahvo_lock, flags);
+	w = tahvo_read_reg(reg);
+	w &= ~clear;
+	w |= set;
+	tahvo_write_reg(reg, w);
+	spin_unlock_irqrestore(&tahvo_lock, flags);
+}
+
+/*
+ * Disable given TAHVO interrupt
+ */
+void tahvo_disable_irq(int id)
+{
+	unsigned long flags;
+	u16 mask;
+
+	spin_lock_irqsave(&tahvo_lock, flags);
+	mask = tahvo_read_reg(TAHVO_REG_IMR);
+	mask |= 1 << id;
+	tahvo_write_reg(TAHVO_REG_IMR, mask);
+	spin_unlock_irqrestore(&tahvo_lock, flags);
+}
+
+/*
+ * Enable given TAHVO interrupt
+ */
+void tahvo_enable_irq(int id)
+{
+	unsigned long flags;
+	u16 mask;
+
+	spin_lock_irqsave(&tahvo_lock, flags);
+	mask = tahvo_read_reg(TAHVO_REG_IMR);
+	mask &= ~(1 << id);
+	tahvo_write_reg(TAHVO_REG_IMR, mask);
+	spin_unlock_irqrestore(&tahvo_lock, flags);
+}
+
+/*
+ * Acknowledge given TAHVO interrupt
+ */
+void tahvo_ack_irq(int id)
+{
+	tahvo_write_reg(TAHVO_REG_IDR, 1 << id);
+}
+
+static int tahvo_7bit_backlight;
+
+int tahvo_get_backlight_level(void)
+{
+	int mask;
+
+	if (tahvo_7bit_backlight)
+		mask = 0x7f;
+	else
+		mask = 0x0f;
+	return tahvo_read_reg(TAHVO_REG_LEDPWMR) & mask;
+}
+
+int tahvo_get_max_backlight_level(void)
+{
+	if (tahvo_7bit_backlight)
+		return 0x7f;
+	else
+		return 0x0f;
+}
+
+void tahvo_set_backlight_level(int level)
+{
+	int max_level;
+
+	max_level = tahvo_get_max_backlight_level();
+	if (level > max_level)
+		level = max_level;
+	tahvo_write_reg(TAHVO_REG_LEDPWMR, level);
+}
+
+/*
+ * TAHVO interrupt handler. Only schedules the tasklet.
+ */
+static irqreturn_t tahvo_irq_handler(int irq, void *dev_id)
+{
+	tasklet_schedule(&tahvo_tasklet);
+	return IRQ_HANDLED;
+}
+
+/*
+ * Tasklet handler
+ */
+static void tahvo_tasklet_handler(unsigned long data)
+{
+	struct tahvo_irq_handler_desc *hnd;
+	u16 id;
+	u16 im;
+	int i;
+
+	for (;;) {
+		id = tahvo_read_reg(TAHVO_REG_IDR);
+		im = ~tahvo_read_reg(TAHVO_REG_IMR);
+		id &= im;
+
+		if (!id)
+			break;
+
+		for (i = 0; id != 0; i++, id >>= 1) {
+			if (!(id & 1))
+				continue;
+			hnd = &tahvo_irq_handlers[i];
+			if (hnd->func == NULL) {
+				/* Spurious tahvo interrupt - just ack it */
+				printk(KERN_INFO "Spurious Tahvo interrupt "
+						 "(id %d)\n", i);
+				tahvo_disable_irq(i);
+				tahvo_ack_irq(i);
+				continue;
+			}
+			hnd->func(hnd->arg);
+			/*
+			 * Don't acknowledge the interrupt here
+			 * It must be done explicitly
+			 */
+		}
+	}
+}
+
+/*
+ * Register the handler for a given TAHVO interrupt source.
+ */
+int tahvo_request_irq(int id, void *irq_handler, unsigned long arg, char *name)
+{
+	struct tahvo_irq_handler_desc *hnd;
+
+	if (irq_handler == NULL || id >= MAX_TAHVO_IRQ_HANDLERS ||
+	    name == NULL) {
+		printk(KERN_ERR PFX "Invalid arguments to %s\n",
+		       __FUNCTION__);
+		return -EINVAL;
+	}
+	hnd = &tahvo_irq_handlers[id];
+	if (hnd->func != NULL) {
+		printk(KERN_ERR PFX "IRQ %d already reserved\n", id);
+		return -EBUSY;
+	}
+	printk(KERN_INFO PFX "Registering interrupt %d for device %s\n",
+	       id, name);
+	hnd->func = irq_handler;
+	hnd->arg = arg;
+	strlcpy(hnd->name, name, sizeof(hnd->name));
+
+	tahvo_ack_irq(id);
+	tahvo_enable_irq(id);
+
+	return 0;
+}
+
+/*
+ * Unregister the handler for a given TAHVO interrupt source.
+ */
+void tahvo_free_irq(int id)
+{
+	struct tahvo_irq_handler_desc *hnd;
+
+	if (id >= MAX_TAHVO_IRQ_HANDLERS) {
+		printk(KERN_ERR PFX "Invalid argument to %s\n",
+		       __FUNCTION__);
+		return;
+	}
+	hnd = &tahvo_irq_handlers[id];
+	if (hnd->func == NULL) {
+		printk(KERN_ERR PFX "IRQ %d already freed\n", id);
+		return;
+	}
+
+	tahvo_disable_irq(id);
+	hnd->func = NULL;
+}
+
+/**
+ * tahvo_probe - Probe for Tahvo ASIC
+ * @dev: the Tahvo device
+ *
+ * Probe for the Tahvo ASIC and allocate memory
+ * for its device-struct if found
+ */
+static int __devinit tahvo_probe(struct device *dev)
+{
+	const struct omap_em_asic_bb5_config * em_asic_config;
+	int rev, id, ret;
+
+	/* Prepare tasklet */
+	tasklet_init(&tahvo_tasklet, tahvo_tasklet_handler, 0);
+
+	em_asic_config = omap_get_config(OMAP_TAG_EM_ASIC_BB5,
+					 struct omap_em_asic_bb5_config);
+	if (em_asic_config == NULL) {
+		printk(KERN_ERR PFX "Unable to retrieve config data\n");
+		return -ENODATA;
+	}
+
+	tahvo_initialized = 1;
+
+	rev = tahvo_read_reg(TAHVO_REG_ASICR);
+
+	id = (rev >> 8) & 0xff;
+	if (id == 0x03) {
+		if ((rev & 0xff) >= 0x50)
+			tahvo_7bit_backlight = 1;
+	} else if (id == 0x0b) {
+		tahvo_is_betty = 1;
+		tahvo_7bit_backlight = 1;
+	} else {
+		printk(KERN_ERR "Tahvo/Betty chip not found");
+		return -ENODEV;
+	}
+
+	printk(KERN_INFO "%s v%d.%d found\n", tahvo_is_betty ? "Betty" : "Tahvo",
+	       (rev >> 4) & 0x0f, rev & 0x0f);
+
+	tahvo_irq_pin = em_asic_config->tahvo_irq_gpio;
+
+	if ((ret = omap_request_gpio(tahvo_irq_pin)) < 0) {
+		printk(KERN_ERR PFX "Unable to reserve IRQ GPIO\n");
+		return ret;
+	}
+
+	/* Set the pin as input */
+	omap_set_gpio_direction(tahvo_irq_pin, 1);
+
+	/* Rising edge triggers the IRQ */
+	set_irq_type(OMAP_GPIO_IRQ(tahvo_irq_pin), IRQT_RISING);
+
+	/* Mask all TAHVO interrupts */
+	tahvo_write_reg(TAHVO_REG_IMR, 0xffff);
+
+	ret = request_irq(OMAP_GPIO_IRQ(tahvo_irq_pin), tahvo_irq_handler, 0,
+			  "tahvo", 0);
+	if (ret < 0) {
+		printk(KERN_ERR PFX "Unable to register IRQ handler\n");
+		omap_free_gpio(tahvo_irq_pin);
+		return ret;
+	}
+#ifdef CONFIG_CBUS_TAHVO_USER
+	/* Initialize user-space interface */
+	if (tahvo_user_init() < 0) {
+		printk(KERN_ERR "Unable to initialize driver\n");
+		free_irq(OMAP_GPIO_IRQ(tahvo_irq_pin), 0);
+		omap_free_gpio(tahvo_irq_pin);
+		return ret;
+	}
+#endif
+	return 0;
+}
+
+static int tahvo_remove(struct device *dev)
+{
+#ifdef CONFIG_CBUS_TAHVO_USER
+	tahvo_user_cleanup();
+#endif
+	/* Mask all TAHVO interrupts */
+	tahvo_write_reg(TAHVO_REG_IMR, 0xffff);
+	free_irq(OMAP_GPIO_IRQ(tahvo_irq_pin), 0);
+	omap_free_gpio(tahvo_irq_pin);
+	tasklet_kill(&tahvo_tasklet);
+
+	return 0;
+}
+
+static void tahvo_device_release(struct device *dev)
+{
+	complete(&device_release);
+}
+
+static struct device_driver tahvo_driver = {
+	.name		= "tahvo",
+	.bus		= &platform_bus_type,
+	.probe		= tahvo_probe,
+	.remove		= tahvo_remove,
+};
+
+static struct platform_device tahvo_device = {
+	.name		= "tahvo",
+	.id		= -1,
+	.dev = {
+		.release = tahvo_device_release,
+	}
+};
+
+/**
+ * tahvo_init - initialise Tahvo driver
+ *
+ * Initialise the Tahvo driver and return 0 if everything worked ok
+ */
+static int __init tahvo_init(void)
+{
+	int ret = 0;
+
+	printk(KERN_INFO "Tahvo/Betty driver initialising\n");
+
+	init_completion(&device_release);
+
+	if ((ret = driver_register(&tahvo_driver)) < 0)
+		return ret;
+
+	if ((ret = platform_device_register(&tahvo_device)) < 0) {
+		driver_unregister(&tahvo_driver);
+		return ret;
+	}
+	return 0;
+}
+
+/*
+ * Cleanup
+ */
+static void __exit tahvo_exit(void)
+{
+	platform_device_unregister(&tahvo_device);
+	driver_unregister(&tahvo_driver);
+	wait_for_completion(&device_release);
+}
+
+EXPORT_SYMBOL(tahvo_request_irq);
+EXPORT_SYMBOL(tahvo_free_irq);
+EXPORT_SYMBOL(tahvo_enable_irq);
+EXPORT_SYMBOL(tahvo_disable_irq);
+EXPORT_SYMBOL(tahvo_ack_irq);
+EXPORT_SYMBOL(tahvo_read_reg);
+EXPORT_SYMBOL(tahvo_write_reg);
+EXPORT_SYMBOL(tahvo_get_backlight_level);
+EXPORT_SYMBOL(tahvo_get_max_backlight_level);
+EXPORT_SYMBOL(tahvo_set_backlight_level);
+
+subsys_initcall(tahvo_init);
+module_exit(tahvo_exit);
+
+MODULE_DESCRIPTION("Tahvo ASIC control");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Juha Yrjl, David Weinehall, and Mikko Ylinen");

drivers/cbus/tahvo.h

+/*
+ * drivers/cbus/tahvo.h
+ *
+ * Copyright (C) 2004, 2005 Nokia Corporation
+ *
+ * Written by Juha Yrjl <juha.yrjola@nokia.com> and
+ *	      David Weinehall <david.weinehall@nokia.com>
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file "COPYING" in the main directory of this
+ * archive for more details.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef __DRIVERS_CBUS_TAHVO_H
+#define __DRIVERS_CBUS_TAHVO_H
+
+#include <linux/types.h>
+
+/* Registers */
+#define TAHVO_REG_ASICR		0x00	/* ASIC ID & revision */
+#define TAHVO_REG_IDR		0x01	/* Interrupt ID */
+#define TAHVO_REG_IDSR		0x02	/* Interrupt status */
+#define TAHVO_REG_IMR		0x03	/* Interrupt mask */
+#define TAHVO_REG_LEDPWMR	0x05	/* LED PWM */
+#define TAHVO_REG_USBR		0x06	/* USB control */
+#define TAHVO_REG_MAX		0x0d
+
+/* Interrupt sources */
+#define TAHVO_INT_VBUSON	0
+
+#define MAX_TAHVO_IRQ_HANDLERS	8
+
+int tahvo_read_reg(int reg);
+void tahvo_write_reg(int reg, u16 val);
+void tahvo_set_clear_reg_bits(int reg, u16 set, u16 clear);
+int tahvo_request_irq(int id, void *irq_handler, unsigned long arg, char *name);
+void tahvo_free_irq(int id);
+void tahvo_enable_irq(int id);
+void tahvo_disable_irq(int id);
+void tahvo_ack_irq(int id);
+int tahvo_get_backlight_level(void);
+int tahvo_get_max_backlight_level(void);
+void tahvo_set_backlight_level(int level);
+
+#ifdef CONFIG_CBUS_TAHVO_USER
+int tahvo_user_init(void);
+void tahvo_user_cleanup(void);
+#endif
+
+extern spinlock_t tahvo_lock;
+
+#endif /* __DRIVERS_CBUS_TAHVO_H */

drivers/cbus/user_retu_tahvo.h

+/**
+ * drivers/cbus/user_retu_tahvo.h
+ *
+ * Copyright (C) 2004, 2005 Nokia Corporation
+ *
+ * Written by Mikko Ylinen <mikko.k.ylinen@nokia.com>
+ *
+ * Definitions and types used by both retu-user and tahvo-user.
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file "COPYING" in the main directory of this
+ * archive for more details.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef _USER_RETU_TAHVO_H
+#define _USER_RETU_TAHVO_H
+
+/* Chip IDs */
+#define CHIP_RETU	1
+#define CHIP_TAHVO	2
+
+/* Register access type bits */
+#define READ_ONLY		1
+#define WRITE_ONLY		2
+#define READ_WRITE		3
+#define TOGGLE			4
+
+#define MASK(field)		((u16)(field & 0xFFFF))
+#define REG(field)		((u16)((field >> 16) & 0x3F))
+
+/*** IOCTL definitions. These should be kept in sync with user space **********/
+
+#define URT_IOC_MAGIC '`'
+
+/*
+ * IOCTL function naming conventions:
+ * ==================================
+ *  0 -- No argument and return value
+ *  S -- Set through a pointer
+ *  T -- Tell directly with the argument value
+ *  G -- Reply by setting through a pointer
+ *  Q -- response is on the return value
+ *  X -- S and G atomically
+ *  H -- T and Q atomically
+ */
+
+/* General */
+#define URT_IOCT_IRQ_SUBSCR		_IO(URT_IOC_MAGIC, 0)
+
+/* RETU */
+#define RETU_IOCH_READ			_IO(URT_IOC_MAGIC, 1)
+#define RETU_IOCX_WRITE			_IO(URT_IOC_MAGIC, 2)
+#define RETU_IOCH_ADC_READ		_IO(URT_IOC_MAGIC, 3)
+
+/* TAHVO */
+#define TAHVO_IOCH_READ			_IO(URT_IOC_MAGIC, 4)
+#define TAHVO_IOCX_WRITE		_IO(URT_IOC_MAGIC, 5)
+
+/* This structure is used for writing RETU/TAHVO registers */
+struct retu_tahvo_write_parms {
+    u32	field;
+    u16	value;
+    u8	result;
+};
+
+#endif