Input: add matrix keypad driver for Cirrus EP93xx

This is a keyboard driver for the Cirrus Logic EP93xx keypad matrix
peripheral. This driver is based on the pxa27x_keypad driver.

[dtor@mail.ru: Plug in input_dev->keycode so keymap can be changed
		from userspace.]
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

arch/arm/mach-ep93xx/include/mach/ep93xx_keypad.h

+/*
+ * arch/arm/mach-ep93xx/include/mach/ep93xx_keypad.h
+ */
+
+#ifndef __ASM_ARCH_EP93XX_KEYPAD_H
+#define __ASM_ARCH_EP93XX_KEYPAD_H
+
+#define MAX_MATRIX_KEY_ROWS		(8)
+#define MAX_MATRIX_KEY_COLS		(8)
+
+/* flags for the ep93xx_keypad driver */
+#define EP93XX_KEYPAD_DISABLE_3_KEY	(1<<0)	/* disable 3-key reset */
+#define EP93XX_KEYPAD_DIAG_MODE		(1<<1)	/* diagnostic mode */
+#define EP93XX_KEYPAD_BACK_DRIVE	(1<<2)	/* back driving mode */
+#define EP93XX_KEYPAD_TEST_MODE		(1<<3)	/* scan only column 0 */
+#define EP93XX_KEYPAD_KDIV		(1<<4)	/* 1/4 clock or 1/16 clock */
+#define EP93XX_KEYPAD_AUTOREPEAT	(1<<5)	/* enable key autorepeat */
+
+/**
+ * struct ep93xx_keypad_platform_data - platform specific device structure
+ * @matrix_key_rows:		number of rows in the keypad matrix
+ * @matrix_key_cols:		number of columns in the keypad matrix
+ * @matrix_key_map:		array of keycodes defining the keypad matrix
+ * @matrix_key_map_size:	ARRAY_SIZE(matrix_key_map)
+ * @debounce:			debounce start count; terminal count is 0xff
+ * @prescale:			row/column counter pre-scaler load value
+ * @flags:			see above
+ */
+struct ep93xx_keypad_platform_data {
+	unsigned int	matrix_key_rows;
+	unsigned int	matrix_key_cols;
+	unsigned int	*matrix_key_map;
+	int		matrix_key_map_size;
+	unsigned int	debounce;
+	unsigned int	prescale;
+	unsigned int	flags;
+};
+
+/* macro for creating the matrix_key_map table */
+#define KEY(row, col, val)	(((row) << 28) | ((col) << 24) | (val))
+
+#endif	/* __ASM_ARCH_EP93XX_KEYPAD_H */

drivers/input/keyboard/Kconfig

@@ -332,4 +332,14 @@ config KEYBOARD_SH_KEYSC
 
 	  To compile this driver as a module, choose M here: the
 	  module will be called sh_keysc.
++
+config KEYBOARD_EP93XX
+	tristate "EP93xx Matrix Keypad support"
+	depends on ARCH_EP93XX
+	help
+	  Say Y here to enable the matrix keypad on the Cirrus EP93XX.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called ep93xx_keypad.
+
 endif

drivers/input/keyboard/Makefile

@@ -28,3 +28,4 @@ obj-$(CONFIG_KEYBOARD_HP7XX)		+= jornada720_kbd.o
 obj-$(CONFIG_KEYBOARD_MAPLE)		+= maple_keyb.o
 obj-$(CONFIG_KEYBOARD_BFIN)		+= bf54x-keys.o
 obj-$(CONFIG_KEYBOARD_SH_KEYSC)		+= sh_keysc.o
+obj-$(CONFIG_KEYBOARD_EP93XX)		+= ep93xx_keypad.o

drivers/input/keyboard/ep93xx_keypad.c

+/*
+ * Driver for the Cirrus EP93xx matrix keypad controller.
+ *
+ * Copyright (c) 2008 H Hartley Sweeten <hsweeten@visionengravers.com>
+ *
+ * Based on the pxa27x matrix keypad controller by Rodolfo Giometti.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * NOTE:
+ *
+ * The 3-key reset is triggered by pressing the 3 keys in
+ * Row 0, Columns 2, 4, and 7 at the same time.  This action can
+ * be disabled by setting the EP93XX_KEYPAD_DISABLE_3_KEY flag.
+ *
+ * Normal operation for the matrix does not autorepeat the key press.
+ * This action can be enabled by setting the EP93XX_KEYPAD_AUTOREPEAT
+ * flag.
+ */
+
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/input.h>
+#include <linux/clk.h>
+
+#include <mach/hardware.h>
+#include <mach/gpio.h>
+#include <mach/ep93xx_keypad.h>
+
+/*
+ * Keypad Interface Register offsets
+ */
+#define KEY_INIT		0x00	/* Key Scan Initialization register */
+#define KEY_DIAG		0x04	/* Key Scan Diagnostic register */
+#define KEY_REG			0x08	/* Key Value Capture register */
+
+/* Key Scan Initialization Register bit defines */
+#define KEY_INIT_DBNC_MASK	(0x00ff0000)
+#define KEY_INIT_DBNC_SHIFT	(16)
+#define KEY_INIT_DIS3KY		(1<<15)
+#define KEY_INIT_DIAG		(1<<14)
+#define KEY_INIT_BACK		(1<<13)
+#define KEY_INIT_T2		(1<<12)
+#define KEY_INIT_PRSCL_MASK	(0x000003ff)
+#define KEY_INIT_PRSCL_SHIFT	(0)
+
+/* Key Scan Diagnostic Register bit defines */
+#define KEY_DIAG_MASK		(0x0000003f)
+#define KEY_DIAG_SHIFT		(0)
+
+/* Key Value Capture Register bit defines */
+#define KEY_REG_K		(1<<15)
+#define KEY_REG_INT		(1<<14)
+#define KEY_REG_2KEYS		(1<<13)
+#define KEY_REG_1KEY		(1<<12)
+#define KEY_REG_KEY2_MASK	(0x00000fc0)
+#define KEY_REG_KEY2_SHIFT	(6)
+#define KEY_REG_KEY1_MASK	(0x0000003f)
+#define KEY_REG_KEY1_SHIFT	(0)
+
+#define keypad_readl(off)	__raw_readl(keypad->mmio_base + (off))
+#define keypad_writel(v, off)	__raw_writel((v), keypad->mmio_base + (off))
+
+#define MAX_MATRIX_KEY_NUM	(MAX_MATRIX_KEY_ROWS * MAX_MATRIX_KEY_COLS)
+
+struct ep93xx_keypad {
+	struct ep93xx_keypad_platform_data *pdata;
+
+	struct clk *clk;
+	struct input_dev *input_dev;
+	void __iomem *mmio_base;
+
+	int irq;
+	int enabled;
+
+	int key1;
+	int key2;
+
+	unsigned int matrix_keycodes[MAX_MATRIX_KEY_NUM];
+};
+
+static void ep93xx_keypad_build_keycode(struct ep93xx_keypad *keypad)
+{
+	struct ep93xx_keypad_platform_data *pdata = keypad->pdata;
+	struct input_dev *input_dev = keypad->input_dev;
+	int i;
+
+	for (i = 0; i < pdata->matrix_key_map_size; i++) {
+		unsigned int key = pdata->matrix_key_map[i];
+		int row = (key >> 28) & 0xf;
+		int col = (key >> 24) & 0xf;
+		int code = key & 0xffffff;
+
+		keypad->matrix_keycodes[(row << 3) + col] = code;
+		__set_bit(code, input_dev->keybit);
+	}
+}
+
+static irqreturn_t ep93xx_keypad_irq_handler(int irq, void *dev_id)
+{
+	struct ep93xx_keypad *keypad = dev_id;
+	struct input_dev *input_dev = keypad->input_dev;
+	unsigned int status = keypad_readl(KEY_REG);
+	int keycode, key1, key2;
+
+	keycode = (status & KEY_REG_KEY1_MASK) >> KEY_REG_KEY1_SHIFT;
+	key1 = keypad->matrix_keycodes[keycode];
+
+	keycode = (status & KEY_REG_KEY2_MASK) >> KEY_REG_KEY2_SHIFT;
+	key2 = keypad->matrix_keycodes[keycode];
+
+	if (status & KEY_REG_2KEYS) {
+		if (keypad->key1 && key1 != keypad->key1 && key2 != keypad->key1)
+			input_report_key(input_dev, keypad->key1, 0);
+
+		if (keypad->key2 && key1 != keypad->key2 && key2 != keypad->key2)
+			input_report_key(input_dev, keypad->key2, 0);
+
+		input_report_key(input_dev, key1, 1);
+		input_report_key(input_dev, key2, 1);
+
+		keypad->key1 = key1;
+		keypad->key2 = key2;
+
+	} else if (status & KEY_REG_1KEY) {
+		if (keypad->key1 && key1 != keypad->key1)
+			input_report_key(input_dev, keypad->key1, 0);
+
+		if (keypad->key2 && key1 != keypad->key2)
+			input_report_key(input_dev, keypad->key2, 0);
+
+		input_report_key(input_dev, key1, 1);
+
+		keypad->key1 = key1;
+		keypad->key2 = 0;
+
+	} else {
+		input_report_key(input_dev, keypad->key1, 0);
+		input_report_key(input_dev, keypad->key2, 0);
+
+		keypad->key1 = keypad->key2 = 0;
+	}
+	input_sync(input_dev);
+
+	return IRQ_HANDLED;
+}
+
+static void ep93xx_keypad_config(struct ep93xx_keypad *keypad)
+{
+	struct ep93xx_keypad_platform_data *pdata = keypad->pdata;
+	unsigned int val = 0;
+
+	clk_set_rate(keypad->clk, pdata->flags & EP93XX_KEYPAD_KDIV);
+
+	if (pdata->flags & EP93XX_KEYPAD_DISABLE_3_KEY)
+		val |= KEY_INIT_DIS3KY;
+	if (pdata->flags & EP93XX_KEYPAD_DIAG_MODE)
+		val |= KEY_INIT_DIAG;
+	if (pdata->flags & EP93XX_KEYPAD_BACK_DRIVE)
+		val |= KEY_INIT_BACK;
+	if (pdata->flags & EP93XX_KEYPAD_TEST_MODE)
+		val |= KEY_INIT_T2;
+
+	val |= ((pdata->debounce << KEY_INIT_DBNC_SHIFT) & KEY_INIT_DBNC_MASK);
+
+	val |= ((pdata->prescale << KEY_INIT_PRSCL_SHIFT) & KEY_INIT_PRSCL_MASK);
+
+	keypad_writel(val, KEY_INIT);
+}
+
+static int ep93xx_keypad_open(struct input_dev *pdev)
+{
+	struct ep93xx_keypad *keypad = input_get_drvdata(pdev);
+
+	if (!keypad->enabled) {
+		ep93xx_keypad_config(keypad);
+		clk_enable(keypad->clk);
+		keypad->enabled = 1;
+	}
+
+	return 0;
+}
+
+static void ep93xx_keypad_close(struct input_dev *pdev)
+{
+	struct ep93xx_keypad *keypad = input_get_drvdata(pdev);
+
+	if (keypad->enabled) {
+		clk_disable(keypad->clk);
+		keypad->enabled = 0;
+	}
+}
+
+
+#ifdef CONFIG_PM
+/*
+ * NOTE: I don't know if this is correct, or will work on the ep93xx.
+ *
+ * None of the existing ep93xx drivers have power management support.
+ * But, this is basically what the pxa27x_keypad driver does.
+ */
+static int ep93xx_keypad_suspend(struct platform_device *pdev,
+				 pm_message_t state)
+{
+	struct ep93xx_keypad *keypad = platform_get_drvdata(pdev);
+	struct input_dev *input_dev = keypad->input_dev;
+
+	mutex_lock(&input_dev->mutex);
+
+	if (keypad->enabled) {
+		clk_disable(keypad->clk);
+		keypad->enabled = 0;
+	}
+
+	mutex_unlock(&input_dev->mutex);
+
+	if (device_may_wakeup(&pdev->dev))
+		enable_irq_wake(keypad->irq);
+
+	return 0;
+}
+
+static int ep93xx_keypad_resume(struct platform_device *pdev)
+{
+	struct ep93xx_keypad *keypad = platform_get_drvdata(pdev);
+	struct input_dev *input_dev = keypad->input_dev;
+
+	if (device_may_wakeup(&pdev->dev))
+		disable_irq_wake(keypad->irq);
+
+	mutex_lock(&input_dev->mutex);
+
+	if (input_dev->users) {
+		if (!keypad->enabled) {
+			ep93xx_keypad_config(keypad);
+			clk_enable(keypad->clk);
+			keypad->enabled = 1;
+		}
+	}
+
+	mutex_unlock(&input_dev->mutex);
+
+	return 0;
+}
+#else	/* !CONFIG_PM */
+#define ep93xx_keypad_suspend	NULL
+#define ep93xx_keypad_resume	NULL
+#endif	/* !CONFIG_PM */
+
+static int __devinit ep93xx_keypad_probe(struct platform_device *pdev)
+{
+	struct ep93xx_keypad *keypad;
+	struct ep93xx_keypad_platform_data *pdata = pdev->dev.platform_data;
+	struct input_dev *input_dev;
+	struct resource *res;
+	int irq, err, i, gpio;
+
+	if (!pdata ||
+	    !pdata->matrix_key_rows ||
+	    pdata->matrix_key_rows > MAX_MATRIX_KEY_ROWS ||
+	    !pdata->matrix_key_cols ||
+	    pdata->matrix_key_cols > MAX_MATRIX_KEY_COLS) {
+		dev_err(&pdev->dev, "invalid or missing platform data\n");
+		return -EINVAL;
+	}
+
+	keypad = kzalloc(sizeof(struct ep93xx_keypad), GFP_KERNEL);
+	if (!keypad) {
+		dev_err(&pdev->dev, "failed to allocate driver data\n");
+		return -ENOMEM;
+	}
+
+	keypad->pdata = pdata;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(&pdev->dev, "failed to get keypad irq\n");
+		err = -ENXIO;
+		goto failed_free;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(&pdev->dev, "failed to get I/O memory\n");
+		err = -ENXIO;
+		goto failed_free;
+	}
+
+	res = request_mem_region(res->start, resource_size(res), pdev->name);
+	if (!res) {
+		dev_err(&pdev->dev, "failed to request I/O memory\n");
+		err = -EBUSY;
+		goto failed_free;
+	}
+
+	keypad->mmio_base = ioremap(res->start, resource_size(res));
+	if (keypad->mmio_base == NULL) {
+		dev_err(&pdev->dev, "failed to remap I/O memory\n");
+		err = -ENXIO;
+		goto failed_free_mem;
+	}
+
+	/* Request the needed GPIO's */
+	gpio = EP93XX_GPIO_LINE_ROW0;
+	for (i = 0; i < keypad->pdata->matrix_key_rows; i++, gpio++) {
+		err = gpio_request(gpio, pdev->name);
+		if (err) {
+			dev_err(&pdev->dev, "failed to request gpio-%d\n",
+				gpio);
+			goto failed_free_rows;
+		}
+	}
+
+	gpio = EP93XX_GPIO_LINE_COL0;
+	for (i = 0; i < keypad->pdata->matrix_key_cols; i++, gpio++) {
+		err = gpio_request(gpio, pdev->name);
+		if (err) {
+			dev_err(&pdev->dev, "failed to request gpio-%d\n",
+				gpio);
+			goto failed_free_cols;
+		}
+	}
+
+	keypad->clk = clk_get(&pdev->dev, "key_clk");
+	if (IS_ERR(keypad->clk)) {
+		dev_err(&pdev->dev, "failed to get keypad clock\n");
+		err = PTR_ERR(keypad->clk);
+		goto failed_free_io;
+	}
+
+	/* Create and register the input driver */
+	input_dev = input_allocate_device();
+	if (!input_dev) {
+		dev_err(&pdev->dev, "failed to allocate input device\n");
+		err = -ENOMEM;
+		goto failed_put_clk;
+	}
+
+	keypad->input_dev = input_dev;
+
+	input_dev->name = pdev->name;
+	input_dev->id.bustype = BUS_HOST;
+	input_dev->open = ep93xx_keypad_open;
+	input_dev->close = ep93xx_keypad_close;
+	input_dev->dev.parent = &pdev->dev;
+	input_dev->keycode = keypad->matrix_keycodes;
+	input_dev->keycodesize = sizeof(keypad->matrix_keycodes[0]);
+	input_dev->keycodemax = ARRAY_SIZE(keypad->matrix_keycodes);
+
+	input_set_drvdata(input_dev, keypad);
+
+	input_dev->evbit[0] = BIT_MASK(EV_KEY);
+	if (keypad->pdata->flags & EP93XX_KEYPAD_AUTOREPEAT)
+		input_dev->evbit[0] |= BIT_MASK(EV_REP);
+
+	ep93xx_keypad_build_keycode(keypad);
+	platform_set_drvdata(pdev, keypad);
+
+	err = request_irq(irq, ep93xx_keypad_irq_handler, IRQF_DISABLED,
+				pdev->name, keypad);
+	if (err) {
+		dev_err(&pdev->dev, "failed to request IRQ\n");
+		goto failed_free_dev;
+	}
+
+	keypad->irq = irq;
+
+	/* Register the input device */
+	err = input_register_device(input_dev);
+	if (err) {
+		dev_err(&pdev->dev, "failed to register input device\n");
+		goto failed_free_irq;
+	}
+
+	device_init_wakeup(&pdev->dev, 1);
+
+	return 0;
+
+failed_free_irq:
+	free_irq(irq, pdev);
+	platform_set_drvdata(pdev, NULL);
+failed_free_dev:
+	input_free_device(input_dev);
+failed_put_clk:
+	clk_put(keypad->clk);
+failed_free_io:
+	i = keypad->pdata->matrix_key_cols - 1;
+	gpio = EP93XX_GPIO_LINE_COL0 + i;
+failed_free_cols:
+	for ( ; i >= 0; i--, gpio--)
+		gpio_free(gpio);
+	i = keypad->pdata->matrix_key_rows - 1;
+	gpio = EP93XX_GPIO_LINE_ROW0 + i;
+failed_free_rows:
+	for ( ; i >= 0; i--, gpio--)
+		gpio_free(gpio);
+	iounmap(keypad->mmio_base);
+failed_free_mem:
+	release_mem_region(res->start, resource_size(res));
+failed_free:
+	kfree(keypad);
+	return err;
+}
+
+static int __devexit ep93xx_keypad_remove(struct platform_device *pdev)
+{
+	struct ep93xx_keypad *keypad = platform_get_drvdata(pdev);
+	struct resource *res;
+	int i, gpio;
+
+	free_irq(keypad->irq, pdev);
+
+	platform_set_drvdata(pdev, NULL);
+
+	if (keypad->enabled)
+		clk_disable(keypad->clk);
+	clk_put(keypad->clk);
+
+	input_unregister_device(keypad->input_dev);
+
+	i = keypad->pdata->matrix_key_cols - 1;
+	gpio = EP93XX_GPIO_LINE_COL0 + i;
+	for ( ; i >= 0; i--, gpio--)
+		gpio_free(gpio);
+
+	i = keypad->pdata->matrix_key_rows - 1;
+	gpio = EP93XX_GPIO_LINE_ROW0 + i;
+	for ( ; i >= 0; i--, gpio--)
+		gpio_free(gpio);
+
+	iounmap(keypad->mmio_base);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	release_mem_region(res->start, resource_size(res));
+
+	kfree(keypad);
+
+	return 0;
+}
+
+static struct platform_driver ep93xx_keypad_driver = {
+	.driver		= {
+		.name	= "ep93xx-keypad",
+		.owner	= THIS_MODULE,
+	},
+	.probe		= ep93xx_keypad_probe,
+	.remove		= __devexit_p(ep93xx_keypad_remove),
+	.suspend	= ep93xx_keypad_suspend,
+	.resume		= ep93xx_keypad_resume,
+};
+
+static int __init ep93xx_keypad_init(void)
+{
+	return platform_driver_register(&ep93xx_keypad_driver);
+}
+
+static void __exit ep93xx_keypad_exit(void)
+{
+	platform_driver_unregister(&ep93xx_keypad_driver);
+}
+
+module_init(ep93xx_keypad_init);
+module_exit(ep93xx_keypad_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("H Hartley Sweeten <hsweeten@visionengravers.com>");
+MODULE_DESCRIPTION("EP93xx Matrix Keypad Controller");
+MODULE_ALIAS("platform:ep93xx-keypad");