I2C: LP5521: Introduce lp5521 LED driver

Introduce n810's lp5521 LED driver.

Signed-off-by: Mathias Nyman <mathias.nyman@nokia.com

Updated to new style i2c driver and to build on current
linux-omap head.
Signed-off-by: Felipe Balbi <felipe.balbi@nokia.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/mach-omap2/board-n800.c

@@ -664,6 +664,10 @@ static struct i2c_board_info __initdata n800_i2c_board_info_2[] = {
 		I2C_BOARD_INFO("tsl2563", 0x29),
 		.type		= "tsl2563",
 	},
+	{
+		I2C_BOARD_INFO("lp5521", 0x32),
+		.type		= "lp5521",
+	},
 };
 
 void __init nokia_n800_common_init(void)

drivers/i2c/chips/Kconfig

@@ -212,6 +212,13 @@ config SENSORS_TSL2563
          This driver can also be built as a module.  If so, the module
          will be called tsl2563.
 
+config LP5521
+	tristate "LP5521 LED driver chip"
+	depends on I2C
+	help
+	  If you say yes here you get support for the National Semiconductor
+	  LP5521 LED driver.
+
 config MENELAUS
 	bool "TWL92330/Menelaus PM chip"
 	depends on I2C=y && ARCH_OMAP24XX

drivers/i2c/chips/Makefile

@@ -30,6 +30,7 @@ obj-$(CONFIG_TWL4030_POWEROFF)	+= twl4030-poweroff.o
 obj-$(CONFIG_TWL4030_PWRBUTTON)	+= twl4030-pwrbutton.o
 obj-$(CONFIG_TWL4030_MADC)	+= twl4030-madc.o
 obj-$(CONFIG_RTC_X1205_I2C)	+= x1205.o
+obj-$(CONFIG_LP5521)		+= lp5521.o
 
 ifeq ($(CONFIG_I2C_DEBUG_CHIP),y)
 EXTRA_CFLAGS += -DDEBUG

drivers/i2c/chips/lp5521.c

+/*
+ * drivers/i2c/chips/lp5521.c
+ *
+ * Copyright (C) 2007 Nokia Corporation
+ *
+ * Written by Mathias Nyman <mathias.nyman@nokia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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/i2c.h>
+#include <linux/mutex.h>
+#include <asm/arch/gpio.h>
+
+#define LP5521_DRIVER_NAME		"lp5521"
+
+#ifdef LED_CONNECTED_WRONG
+#define LP5521_REG_R_PWM		0x04
+#define LP5521_REG_B_PWM		0x02
+#else
+#define LP5521_REG_R_PWM		0x02
+#define LP5521_REG_B_PWM		0x04
+#endif
+#define LP5521_REG_ENABLE		0x00
+#define LP5521_REG_OP_MODE		0x01
+#define LP5521_REG_G_PWM		0x03
+#define LP5521_REG_R_CNTRL		0x05
+#define LP5521_REG_G_CNTRL		0x06
+#define LP5521_REG_B_CNTRL		0x07
+#define LP5521_REG_MISC			0x08
+#define LP5521_REG_R_CHANNEL_PC		0x09
+#define LP5521_REG_G_CHANNEL_PC		0x0a
+#define LP5521_REG_B_CHANNEL_PC		0x0b
+#define LP5521_REG_STATUS		0x0c
+#define LP5521_REG_RESET		0x0d
+#define LP5521_REG_GPO			0x0e
+#define LP5521_REG_R_PROG_MEM		0x10
+#define LP5521_REG_G_PROG_MEM		0x30
+#define LP5521_REG_B_PROG_MEM		0x50
+
+#define LP5521_MODE_LOAD		"load"
+#define LP5521_MODE_RUN			"run"
+#define LP5521_MODE_DIRECT_CONTROL	"direct"
+
+#define LP5521_CURRENT_1m5		0x0f
+#define LP5521_CURRENT_3m1		0x1f
+#define LP5521_CURRENT_4m7		0x2f
+#define LP5521_CURRENT_6m3		0x3f
+#define LP5521_CURRENT_7m9		0x4f
+#define LP5521_CURRENT_9m5		0x5f
+#define LP5521_CURRENT_11m1		0x6f
+#define LP5521_CURRENT_12m7		0x7f
+#define LP5521_CURRENT_14m3		0x8f
+#define LP5521_CURRENT_15m9		0x9f
+#define LP5521_CURRENT_17m5		0xaf
+#define LP5521_CURRENT_19m1		0xbf
+#define LP5521_CURRENT_20m7		0xcf
+#define LP5521_CURRENT_22m3		0xdf
+#define LP5521_CURRENT_23m9		0xef
+#define LP5521_CURRENT_25m5		0xff
+
+#define LP5521_PROGRAM_LENGTH		32	/* in bytes */
+
+struct lp5521_chip {
+	struct mutex		lock;
+	struct i2c_client	*client;
+	char			*mode;
+	int			red;
+	int			green;
+	int			blue;
+};
+
+static int lp5521_set_mode(struct lp5521_chip *chip, char *mode);
+
+static int lp5521_write(struct i2c_client *client, u8 reg, u8 value)
+{
+	return i2c_smbus_write_byte_data(client, reg, value);
+}
+
+static int lp5521_read(struct i2c_client *client, u8 reg, u8 *buf)
+{
+	s32 ret = i2c_smbus_read_byte_data(client, reg);
+
+	if (ret < 0)
+		return -EIO;
+
+	*buf = ret;
+	return 0;
+}
+
+static int lp5521_configure(struct i2c_client *client)
+{
+	int ret = 0;
+
+	/* Enable chip and set light to logarithmic mode*/
+	ret |= lp5521_write(client, LP5521_REG_ENABLE, 0xc0);
+
+	/* setting all color pwms to direct control mode */
+	ret |= lp5521_write(client, LP5521_REG_OP_MODE, 0x3f);
+
+	/* setting current to 4.7 mA for all channels */
+	ret |= lp5521_write(client, LP5521_REG_R_CNTRL, LP5521_CURRENT_4m7);
+	ret |= lp5521_write(client, LP5521_REG_G_CNTRL, LP5521_CURRENT_4m7);
+	ret |= lp5521_write(client, LP5521_REG_B_CNTRL, LP5521_CURRENT_4m7);
+
+	/* Enable auto-powersave, set charge pump to auto, red to battery */
+	ret |= lp5521_write(client, LP5521_REG_MISC, 0x3c);
+
+	/* initialize all channels pwm to zero */
+	ret |= lp5521_write(client, LP5521_REG_R_PWM, 0);
+	ret |= lp5521_write(client, LP5521_REG_G_PWM, 0);
+	ret |= lp5521_write(client, LP5521_REG_B_PWM, 0);
+
+	/* Not much can be done about errors at this point */
+	return ret;
+}
+
+static int lp5521_load_program(struct lp5521_chip *chip, u8 *pattern)
+{
+	struct i2c_client *client = chip->client;
+	int ret = 0;
+
+	/* Enter load program mode for all led channels */
+	ret |= lp5521_write(client, LP5521_REG_OP_MODE, 0x15); /* 0001 0101 */
+	if (ret)
+		return ret;
+
+	if (chip->red)
+		ret |= i2c_smbus_write_i2c_block_data(client,
+						      LP5521_REG_R_PROG_MEM,
+						      LP5521_PROGRAM_LENGTH,
+						      pattern);
+	if (chip->green)
+		ret |= i2c_smbus_write_i2c_block_data(client,
+						      LP5521_REG_G_PROG_MEM,
+						      LP5521_PROGRAM_LENGTH,
+						      pattern);
+	if (chip->blue)
+		ret |= i2c_smbus_write_i2c_block_data(client,
+						      LP5521_REG_B_PROG_MEM,
+						      LP5521_PROGRAM_LENGTH,
+						      pattern);
+
+	return ret;
+}
+
+static int lp5521_run_program(struct lp5521_chip *chip)
+{
+	struct i2c_client *client = chip->client;
+	int ret;
+	u8 mask = 0xc0;
+	u8 exec_state = 0;
+	u8 enable_reg;
+
+	ret = lp5521_read(client, LP5521_REG_ENABLE, &enable_reg);
+	if (ret)
+		goto fail;
+
+	enable_reg &= mask;
+
+	/* set all active channels exec state to countinous run*/
+	exec_state |= (chip->red   << 5);
+	exec_state |= (chip->green << 3);
+	exec_state |= (chip->blue  << 1);
+
+	enable_reg |= exec_state;
+
+	ret |= lp5521_write(client, LP5521_REG_ENABLE, enable_reg);
+
+	/* set op-mode to run for active channels, disabled for others */
+	ret |= lp5521_write(client, LP5521_REG_OP_MODE, exec_state);
+
+fail:
+	return ret;
+}
+
+/*--------------------------------------------------------------*/
+/*			Sysfs interface				*/
+/*--------------------------------------------------------------*/
+
+static ssize_t show_active_channels(struct device *dev,
+			    struct device_attribute *attr,
+			    char *buf)
+{
+	struct lp5521_chip *chip = dev_get_drvdata(dev);
+	char channels[4];
+	int pos = 0;
+
+#ifdef LED_CONNECTED_WRONG
+	if (chip->blue)
+		pos += sprintf(channels + pos, "r");
+	if (chip->green)
+		pos += sprintf(channels + pos, "g");
+	if (chip->red)
+		pos += sprintf(channels + pos, "b");
+
+#else
+	if (chip->red)
+		pos += sprintf(channels + pos, "r");
+	if (chip->green)
+		pos += sprintf(channels + pos, "g");
+	if (chip->blue)
+		pos += sprintf(channels + pos, "b");
+#endif
+
+	channels[pos] = '\0';
+
+	return sprintf(buf, "%s\n", channels);
+}
+
+static ssize_t store_active_channels(struct device *dev,
+			     struct device_attribute *attr,
+			     const char *buf, size_t len)
+{
+	struct lp5521_chip *chip = dev_get_drvdata(dev);
+
+	chip->red = 0;
+	chip->green = 0;
+	chip->blue = 0;
+
+#ifdef LED_CONNECTED_WRONG
+	if (strchr(buf, 'r') != NULL)
+		chip->blue = 1;
+	if (strchr(buf, 'b') != NULL)
+		chip->red = 1;
+#else
+	if (strchr(buf, 'r') != NULL)
+		chip->red = 1;
+	if (strchr(buf, 'b') != NULL)
+		chip->blue = 1;
+#endif
+	if (strchr(buf, 'g') != NULL)
+		chip->green = 1;
+
+	return len;
+}
+
+static ssize_t show_color(struct device *dev,
+			    struct device_attribute *attr,
+			    char *buf)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	int ret = 0;
+	u8 r, g, b;
+
+	ret |= lp5521_read(client, LP5521_REG_R_PWM, &r);
+	ret |= lp5521_read(client, LP5521_REG_G_PWM, &g);
+	ret |= lp5521_read(client, LP5521_REG_B_PWM, &b);
+
+	if (ret)
+		return ret;
+
+	return sprintf(buf, "%.2x:%.2x:%.2x\n", r, g, b);
+}
+
+static ssize_t store_color(struct device *dev,
+			     struct device_attribute *attr,
+			     const char *buf, size_t len)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct lp5521_chip *chip = i2c_get_clientdata(client);
+	int ret;
+	unsigned r, g, b;
+
+
+	ret = sscanf(buf, "%2x:%2x:%2x", &r, &g, &b);
+	if (ret != 3)
+		return  -EINVAL;
+
+	mutex_lock(&chip->lock);
+
+	ret = lp5521_write(client, LP5521_REG_R_PWM, (u8)r);
+	ret = lp5521_write(client, LP5521_REG_G_PWM, (u8)g);
+	ret = lp5521_write(client, LP5521_REG_B_PWM, (u8)b);
+
+	mutex_unlock(&chip->lock);
+
+	return len;
+}
+
+static ssize_t store_load(struct device *dev,
+			     struct device_attribute *attr,
+			     const char *buf, size_t len)
+{
+	struct lp5521_chip *chip = dev_get_drvdata(dev);
+	int  ret, nrchars, offset = 0, i = 0;
+	char c[3];
+	unsigned cmd;
+	u8 pattern[LP5521_PROGRAM_LENGTH] = {0};
+
+	while ((offset < len - 1) && (i < LP5521_PROGRAM_LENGTH)) {
+
+		/* separate sscanfs because length is working only for %s */
+		ret = sscanf(buf + offset, "%2s%n ", c, &nrchars);
+		ret = sscanf(c, "%2x", &cmd);
+		if (ret != 1)
+			goto fail;
+		pattern[i] = (u8)cmd;
+
+		offset += nrchars;
+		i++;
+	}
+
+	/* pattern commands are always two bytes long */
+	if (i % 2)
+		goto fail;
+
+	mutex_lock(&chip->lock);
+
+	ret = lp5521_load_program(chip, pattern);
+	mutex_unlock(&chip->lock);
+
+	if (ret) {
+		dev_err(dev, "lp5521 failed loading pattern\n");
+		return ret;
+	}
+
+	return len;
+fail:
+	dev_err(dev, "lp5521 wrong pattern format\n");
+	return -EINVAL;
+}
+
+static ssize_t show_mode(struct device *dev,
+			 struct device_attribute *attr,
+			 char *buf)
+{
+	struct lp5521_chip *chip = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%s\n", chip->mode);
+}
+
+static ssize_t store_mode(struct device *dev,
+			  struct device_attribute *attr,
+			  const char *buf, size_t len)
+{
+	struct lp5521_chip *chip = dev_get_drvdata(dev);
+
+	mutex_lock(&chip->lock);
+
+	if (!strncmp(buf, "run", 3))
+		lp5521_set_mode(chip, LP5521_MODE_RUN);
+	else if (!strncmp(buf, "load", 4))
+		lp5521_set_mode(chip, LP5521_MODE_LOAD);
+	else if (!strncmp(buf, "direct", 6))
+		lp5521_set_mode(chip, LP5521_MODE_DIRECT_CONTROL);
+
+	mutex_unlock(&chip->lock);
+
+	return len;
+}
+
+static ssize_t show_current(struct device *dev,
+			    struct device_attribute *attr,
+			    char *buf)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	int ret = 0;
+	u8 r_curr, g_curr, b_curr;
+
+	ret |= lp5521_read(client, LP5521_REG_R_CNTRL, &r_curr);
+	ret |= lp5521_read(client, LP5521_REG_G_CNTRL, &g_curr);
+	ret |= lp5521_read(client, LP5521_REG_B_CNTRL, &b_curr);
+
+	if (ret)
+		return ret;
+
+	r_curr = r_curr >> 4;
+	g_curr = g_curr >> 4;
+	b_curr = b_curr >> 4;
+
+	if (r_curr == g_curr && g_curr == b_curr)
+		return sprintf(buf, "%x\n", r_curr);
+	else
+		return sprintf(buf, "%x %x %x\n", r_curr, g_curr, b_curr);
+}
+
+static ssize_t store_current(struct device *dev,
+			     struct device_attribute *attr,
+			     const char *buf, size_t len)
+{
+	struct lp5521_chip *chip = dev_get_drvdata(dev);
+	struct i2c_client *client = chip->client;
+	int ret;
+	unsigned curr;
+
+	ret = sscanf(buf, "%1x", &curr);
+	if (ret != 1)
+		return  -EINVAL;
+
+	/* current level is determined by the 4 upper bits, rest is ones */
+	curr = (curr << 4) | 0x0f;
+
+	mutex_lock(&chip->lock);
+
+	ret |= lp5521_write(client, LP5521_REG_R_CNTRL, (u8)curr);
+	ret |= lp5521_write(client, LP5521_REG_G_CNTRL, (u8)curr);
+	ret |= lp5521_write(client, LP5521_REG_B_CNTRL, (u8)curr);
+
+	mutex_unlock(&chip->lock);
+
+	return len;
+}
+
+static DEVICE_ATTR(color, S_IRUGO | S_IWUGO, show_color, store_color);
+static DEVICE_ATTR(load, S_IWUGO, NULL, store_load);
+static DEVICE_ATTR(mode, S_IRUGO | S_IWUGO, show_mode, store_mode);
+static DEVICE_ATTR(active_channels, S_IRUGO | S_IWUGO,
+		   show_active_channels, store_active_channels);
+static DEVICE_ATTR(led_current, S_IRUGO | S_IWUGO, show_current, store_current);
+
+static int lp5521_register_sysfs(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	int ret;
+
+	ret = device_create_file(dev, &dev_attr_color);
+	if (ret)
+		goto fail1;
+	ret = device_create_file(dev, &dev_attr_load);
+	if (ret)
+		goto fail2;
+	ret = device_create_file(dev, &dev_attr_active_channels);
+	if (ret)
+		goto fail3;
+	ret = device_create_file(dev, &dev_attr_mode);
+	if (ret)
+		goto fail4;
+	ret = device_create_file(dev, &dev_attr_led_current);
+	if (ret)
+		goto fail5;
+	return 0;
+
+fail5:
+	device_remove_file(dev, &dev_attr_mode);
+fail4:
+	device_remove_file(dev, &dev_attr_active_channels);
+fail3:
+	device_remove_file(dev, &dev_attr_load);
+fail2:
+	device_remove_file(dev, &dev_attr_color);
+fail1:
+	return ret;
+}
+
+static void lp5521_unregister_sysfs(struct i2c_client *client)
+{
+	struct lp5521_chip *chip = i2c_get_clientdata(client);
+	struct device *dev = &client->dev;
+
+	device_remove_file(dev, &dev_attr_led_current);
+	device_remove_file(dev, &dev_attr_mode);
+	device_remove_file(dev, &dev_attr_active_channels);
+	device_remove_file(dev, &dev_attr_color);
+
+	if (!strcmp(chip->mode, LP5521_MODE_LOAD))
+		device_remove_file(dev, &dev_attr_load);
+}
+
+/*--------------------------------------------------------------*/
+/*			Set chip operating mode			*/
+/*--------------------------------------------------------------*/
+
+static int lp5521_set_mode(struct lp5521_chip *chip, char *mode)
+{
+	struct i2c_client *client = chip->client ;
+	int ret = 0;
+
+	/* if in that mode already do nothing, except for run */
+	if (!strcmp(mode, chip->mode) && strcmp(mode, LP5521_MODE_RUN))
+		return 0;
+
+	if (!strcmp(mode, LP5521_MODE_RUN))
+		ret = lp5521_run_program(chip);
+
+	if (!strcmp(mode, LP5521_MODE_LOAD))
+		ret |= lp5521_write(client, LP5521_REG_OP_MODE, 0x15);
+
+	if (!strcmp(mode, LP5521_MODE_DIRECT_CONTROL))
+		ret |= lp5521_write(client, LP5521_REG_OP_MODE, 0x3F);
+
+	chip->mode = mode;
+
+	return ret;
+}
+
+/*--------------------------------------------------------------*/
+/*			Probe, Attach, Remove			*/
+/*--------------------------------------------------------------*/
+static struct i2c_driver lp5521_driver;
+
+static int lp5521_probe(struct i2c_client *client)
+{
+	struct lp5521_chip *chip;
+	int ret = 0;
+
+	chip = kzalloc(sizeof(*chip), GFP_KERNEL);
+	if (!chip)
+		return -ENOMEM;
+
+	chip->client	= client;
+	strncpy(client->name, LP5521_DRIVER_NAME, I2C_NAME_SIZE);
+	i2c_set_clientdata(client, chip);
+
+	mutex_init(&chip->lock);
+
+	ret = lp5521_configure(client);
+	if (ret < 0) {
+		dev_err(&client->dev, "lp5521 error configuring chip \n");
+		goto fail1;
+	}
+
+	/* Set default values */
+	chip->mode	= LP5521_MODE_DIRECT_CONTROL;
+	chip->red	= 1;
+	chip->green	= 1;
+	chip->blue	= 1;
+
+	ret = lp5521_register_sysfs(client);
+	if (ret)
+		dev_err(&client->dev, "lp5521 registering sysfs failed \n");
+
+	return ret;
+
+fail1:
+	kfree(chip);
+	return ret;
+}
+
+static int lp5521_remove(struct i2c_client *client)
+{
+	struct lp5521_chip *chip = i2c_get_clientdata(client);
+
+	lp5521_unregister_sysfs(client);
+	kfree(chip);
+
+	return 0;
+}
+
+static struct i2c_driver lp5521_driver = {
+	.driver = {
+		.name	= LP5521_DRIVER_NAME,
+	},
+	.probe		= lp5521_probe,
+	.remove		= __exit_p(lp5521_remove),
+};
+
+static int __init lp5521_init(void)
+{
+	return i2c_add_driver(&lp5521_driver);
+}
+
+static void __exit lp5521_exit(void)
+{
+	i2c_del_driver(&lp5521_driver);
+}
+
+MODULE_AUTHOR("Mathias Nyman <mathias.nyman@nokia.com>");
+MODULE_DESCRIPTION("lp5521 LED driver");
+MODULE_LICENSE("GPL");
+
+module_init(lp5521_init);
+module_exit(lp5521_exit);