Merge branch 'for-linus' of git://git.o-hand.com/linux-rpurdie-leds

* 'for-linus' of git://git.o-hand.com/linux-rpurdie-leds:
  leds: Ensure led->trigger is set earlier
  leds: Add support for Philips PCA955x I2C LED drivers
  leds: Fix sparse warnings in leds-h1940 driver
  leds: mark led_classdev.default_trigger as const
  leds: fix unsigned value overflow in atmel pwm driver
  leds: Add pca9532 platform data for Thecus N2100
  leds: Add pca9532 led driver

arch/arm/mach-iop32x/n2100.c

@@ -17,6 +17,7 @@
 #include <linux/mm.h>
 #include <linux/init.h>
 #include <linux/f75375s.h>
+#include <linux/leds-pca9532.h>
 #include <linux/delay.h>
 #include <linux/kernel.h>
 #include <linux/pci.h>
@@ -206,6 +207,53 @@ static struct f75375s_platform_data n2100_f75375s = {
 	.pwm_enable = { 0, 0 },
 };
 
+static struct pca9532_platform_data n2100_leds = {
+	.leds = {
+	{	.name = "n2100:red:satafail0",
+		.state = PCA9532_OFF,
+		.type = PCA9532_TYPE_LED,
+	},
+	{	.name = "n2100:red:satafail1",
+		.state = PCA9532_OFF,
+		.type = PCA9532_TYPE_LED,
+	},
+	{	.name = "n2100:blue:usb",
+		.state = PCA9532_OFF,
+		.type = PCA9532_TYPE_LED,
+	},
+	{ 	.type = PCA9532_TYPE_NONE },
+
+	{ 	.type = PCA9532_TYPE_NONE },
+	{ 	.type = PCA9532_TYPE_NONE },
+	{ 	.type = PCA9532_TYPE_NONE },
+	{	.name = "n2100:red:usb",
+		.state = PCA9532_OFF,
+		.type = PCA9532_TYPE_LED,
+	},
+
+	{	.type = PCA9532_TYPE_NONE }, /* power OFF gpio */
+	{	.type = PCA9532_TYPE_NONE }, /* reset gpio */
+	{	.type = PCA9532_TYPE_NONE },
+	{	.type = PCA9532_TYPE_NONE },
+
+	{	.type = PCA9532_TYPE_NONE },
+	{	.name = "n2100:orange:system",
+		.state = PCA9532_OFF,
+		.type = PCA9532_TYPE_LED,
+	},
+	{	.name = "n2100:red:system",
+		.state = PCA9532_OFF,
+		.type = PCA9532_TYPE_LED,
+	},
+	{	.name = "N2100 beeper"  ,
+		.state =  PCA9532_OFF,
+		.type = PCA9532_TYPE_N2100_BEEP,
+	},
+	},
+	.psc = { 0, 0 },
+	.pwm = { 0, 0 },
+};
+
 static struct i2c_board_info __initdata n2100_i2c_devices[] = {
 	{
 		I2C_BOARD_INFO("rs5c372b", 0x32),
@@ -214,6 +262,10 @@ static struct i2c_board_info __initdata n2100_i2c_devices[] = {
 		I2C_BOARD_INFO("f75375", 0x2e),
 		.platform_data = &n2100_f75375s,
 	},
+	{
+		I2C_BOARD_INFO("pca9532", 0x60),
+		.platform_data = &n2100_leds,
+	},
 };
 
 /*

drivers/leds/Kconfig

@@ -103,6 +103,14 @@ config LEDS_HP6XX
 	  This option enables led support for the handheld
 	  HP Jornada 620/660/680/690.
 
+config LEDS_PCA9532
+	tristate "LED driver for PCA9532 dimmer"
+	depends on LEDS_CLASS && I2C && INPUT && EXPERIMENTAL
+	help
+	  This option enables support for NXP pca9532
+	  led controller. It is generally only usefull
+	  as a platform driver
+
 config LEDS_GPIO
 	tristate "LED Support for GPIO connected LEDs"
 	depends on LEDS_CLASS && GENERIC_GPIO
@@ -147,6 +155,14 @@ config LEDS_CLEVO_MAIL
 	  To compile this driver as a module, choose M here: the
 	  module will be called leds-clevo-mail.
 
+config LEDS_PCA955X
+	tristate "LED Support for PCA955x I2C chips"
+	depends on LEDS_CLASS && I2C
+	help
+	  This option enables support for LEDs connected to PCA955x
+	  LED driver chips accessed via the I2C bus.  Supported
+	  devices include PCA9550, PCA9551, PCA9552, and PCA9553.
+
 comment "LED Triggers"
 
 config LEDS_TRIGGERS

drivers/leds/Makefile

@@ -16,11 +16,13 @@ obj-$(CONFIG_LEDS_WRAP)			+= leds-wrap.o
 obj-$(CONFIG_LEDS_H1940)		+= leds-h1940.o
 obj-$(CONFIG_LEDS_COBALT_QUBE)		+= leds-cobalt-qube.o
 obj-$(CONFIG_LEDS_COBALT_RAQ)		+= leds-cobalt-raq.o
+obj-$(CONFIG_LEDS_PCA9532)		+= leds-pca9532.o
 obj-$(CONFIG_LEDS_GPIO)			+= leds-gpio.o
 obj-$(CONFIG_LEDS_CM_X270)              += leds-cm-x270.o
 obj-$(CONFIG_LEDS_CLEVO_MAIL)		+= leds-clevo-mail.o
 obj-$(CONFIG_LEDS_HP6XX)		+= leds-hp6xx.o
 obj-$(CONFIG_LEDS_FSG)			+= leds-fsg.o
+obj-$(CONFIG_LEDS_PCA955X)		+= leds-pca955x.o
 
 # LED Triggers
 obj-$(CONFIG_LEDS_TRIGGER_TIMER)	+= ledtrig-timer.o

drivers/leds/led-triggers.c

@@ -111,16 +111,17 @@ void led_trigger_set(struct led_classdev *led_cdev, struct led_trigger *trigger)
 			flags);
 		if (led_cdev->trigger->deactivate)
 			led_cdev->trigger->deactivate(led_cdev);
+		led_cdev->trigger = NULL;
 		led_set_brightness(led_cdev, LED_OFF);
 	}
 	if (trigger) {
 		write_lock_irqsave(&trigger->leddev_list_lock, flags);
 		list_add_tail(&led_cdev->trig_list, &trigger->led_cdevs);
 		write_unlock_irqrestore(&trigger->leddev_list_lock, flags);
+		led_cdev->trigger = trigger;
 		if (trigger->activate)
 			trigger->activate(led_cdev);
 	}
-	led_cdev->trigger = trigger;
 }
 EXPORT_SYMBOL_GPL(led_trigger_set);
 

drivers/leds/leds-atmel-pwm.c

@@ -37,7 +37,7 @@ static int __init pwmled_probe(struct platform_device *pdev)
 {
 	const struct gpio_led_platform_data	*pdata;
 	struct pwmled				*leds;
-	unsigned				i;
+	int					i;
 	int					status;
 
 	pdata = pdev->dev.platform_data;

drivers/leds/leds-h1940.c

@@ -23,7 +23,8 @@
 /*
  * Green led.
  */
-void h1940_greenled_set(struct led_classdev *led_dev, enum led_brightness value)
+static void h1940_greenled_set(struct led_classdev *led_dev,
+			       enum led_brightness value)
 {
 	switch (value) {
 	case LED_HALF:
@@ -52,7 +53,8 @@ static struct led_classdev h1940_greenled = {
 /*
  * Red led.
  */
-void h1940_redled_set(struct led_classdev *led_dev, enum led_brightness value)
+static void h1940_redled_set(struct led_classdev *led_dev,
+			     enum led_brightness value)
 {
 	switch (value) {
 	case LED_HALF:
@@ -82,7 +84,8 @@ static struct led_classdev h1940_redled = {
  * Blue led.
  * (it can only be blue flashing led)
  */
-void h1940_blueled_set(struct led_classdev *led_dev, enum led_brightness value)
+static void h1940_blueled_set(struct led_classdev *led_dev,
+			      enum led_brightness value)
 {
 	if (value) {
 		/* flashing Blue */

drivers/leds/leds-pca9532.c

+/*
+ * pca9532.c - 16-bit Led dimmer
+ *
+ * Copyright (C) 2008 Riku Voipio <riku.voipio@movial.fi>
+ *
+ * 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; version 2 of the License.
+ *
+ * Datasheet: http://www.nxp.com/acrobat/datasheets/PCA9532_3.pdf
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/leds.h>
+#include <linux/input.h>
+#include <linux/mutex.h>
+#include <linux/leds-pca9532.h>
+
+static const unsigned short normal_i2c[] = { /*0x60,*/ I2C_CLIENT_END};
+I2C_CLIENT_INSMOD_1(pca9532);
+
+#define PCA9532_REG_PSC(i) (0x2+(i)*2)
+#define PCA9532_REG_PWM(i) (0x3+(i)*2)
+#define PCA9532_REG_LS0  0x6
+#define LED_REG(led) ((led>>2)+PCA9532_REG_LS0)
+#define LED_NUM(led) (led & 0x3)
+
+#define ldev_to_led(c)       container_of(c, struct pca9532_led, ldev)
+
+struct pca9532_data {
+	struct i2c_client *client;
+	struct pca9532_led leds[16];
+	struct mutex update_lock;
+	struct input_dev    *idev;
+	u8 pwm[2];
+	u8 psc[2];
+};
+
+static int pca9532_probe(struct i2c_client *client,
+	const struct i2c_device_id *id);
+static int pca9532_remove(struct i2c_client *client);
+
+static const struct i2c_device_id pca9532_id[] = {
+	{ "pca9532", 0 },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(i2c, pca9532_id);
+
+static struct i2c_driver pca9532_driver = {
+	.driver = {
+		.name   = "pca9532",
+	},
+	.probe  = pca9532_probe,
+	.remove = pca9532_remove,
+	.id_table = pca9532_id,
+};
+
+/* We have two pwm/blinkers, but 16 possible leds to drive. Additionaly,
+ * the clever Thecus people are using one pwm to drive the beeper. So,
+ * as a compromise we average one pwm to the values requested by all
+ * leds that are not ON/OFF.
+ * */
+static int pca9532_setpwm(struct i2c_client *client, int pwm, int blink,
+	enum led_brightness value)
+{
+	int a = 0, b = 0, i = 0;
+	struct pca9532_data *data = i2c_get_clientdata(client);
+	for (i = 0; i < 16; i++) {
+		if (data->leds[i].type == PCA9532_TYPE_LED &&
+			data->leds[i].state == PCA9532_PWM0+pwm) {
+				a++;
+				b += data->leds[i].ldev.brightness;
+		}
+	}
+	if (a == 0) {
+		dev_err(&client->dev,
+		"fear of division by zero %d/%d, wanted %d\n",
+			b, a, value);
+		return -EINVAL;
+	}
+	b = b/a;
+	if (b > 0xFF)
+		return -EINVAL;
+	mutex_lock(&data->update_lock);
+	data->pwm[pwm] = b;
+	i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(pwm),
+		data->pwm[pwm]);
+	data->psc[pwm] = blink;
+	i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(pwm),
+		data->psc[pwm]);
+	mutex_unlock(&data->update_lock);
+	return 0;
+}
+
+/* Set LED routing */
+static void pca9532_setled(struct pca9532_led *led)
+{
+	struct i2c_client *client = led->client;
+	struct pca9532_data *data = i2c_get_clientdata(client);
+	char reg;
+
+	mutex_lock(&data->update_lock);
+	reg = i2c_smbus_read_byte_data(client, LED_REG(led->id));
+	/* zero led bits */
+	reg = reg & ~(0x3<<LED_NUM(led->id)*2);
+	/* set the new value */
+	reg = reg | (led->state << LED_NUM(led->id)*2);
+	i2c_smbus_write_byte_data(client, LED_REG(led->id), reg);
+	mutex_unlock(&data->update_lock);
+}
+
+static void pca9532_set_brightness(struct led_classdev *led_cdev,
+	enum led_brightness value)
+{
+	int err = 0;
+	struct pca9532_led *led = ldev_to_led(led_cdev);
+
+	if (value == LED_OFF)
+		led->state = PCA9532_OFF;
+	else if (value == LED_FULL)
+		led->state = PCA9532_ON;
+	else {
+		led->state = PCA9532_PWM0; /* Thecus: hardcode one pwm */
+		err = pca9532_setpwm(led->client, 0, 0, value);
+		if (err)
+			return; /* XXX: led api doesn't allow error code? */
+	}
+	pca9532_setled(led);
+}
+
+static int pca9532_set_blink(struct led_classdev *led_cdev,
+	unsigned long *delay_on, unsigned long *delay_off)
+{
+	struct pca9532_led *led = ldev_to_led(led_cdev);
+	struct i2c_client *client = led->client;
+	int psc;
+
+	if (*delay_on == 0 && *delay_off == 0) {
+	/* led subsystem ask us for a blink rate */
+		*delay_on  = 1000;
+		*delay_off = 1000;
+	}
+	if (*delay_on != *delay_off || *delay_on > 1690 || *delay_on < 6)
+		return -EINVAL;
+
+	/* Thecus specific: only use PSC/PWM 0 */
+	psc = (*delay_on * 152-1)/1000;
+	return pca9532_setpwm(client, 0, psc, led_cdev->brightness);
+}
+
+int pca9532_event(struct input_dev *dev, unsigned int type, unsigned int code,
+	int value)
+{
+	struct pca9532_data *data = input_get_drvdata(dev);
+
+	if (type != EV_SND && (code != SND_BELL || code != SND_TONE))
+		return -1;
+
+	/* XXX: allow different kind of beeps with psc/pwm modifications */
+	if (value > 1 && value < 32767)
+		data->pwm[1] = 127;
+	else
+		data->pwm[1] = 0;
+
+	dev_info(&dev->dev, "setting beep to %d \n", data->pwm[1]);
+	mutex_lock(&data->update_lock);
+	i2c_smbus_write_byte_data(data->client, PCA9532_REG_PWM(1),
+		data->pwm[1]);
+	mutex_unlock(&data->update_lock);
+
+	return 0;
+}
+
+static int pca9532_configure(struct i2c_client *client,
+	struct pca9532_data *data, struct pca9532_platform_data *pdata)
+{
+	int i, err = 0;
+
+	for (i = 0; i < 2; i++)	{
+		data->pwm[i] = pdata->pwm[i];
+		data->psc[i] = pdata->psc[i];
+		i2c_smbus_write_byte_data(client, PCA9532_REG_PWM(i),
+			data->pwm[i]);
+		i2c_smbus_write_byte_data(client, PCA9532_REG_PSC(i),
+			data->psc[i]);
+	}
+
+	for (i = 0; i < 16; i++) {
+		struct pca9532_led *led = &data->leds[i];
+		struct pca9532_led *pled = &pdata->leds[i];
+		led->client = client;
+		led->id = i;
+		led->type = pled->type;
+		switch (led->type) {
+		case PCA9532_TYPE_NONE:
+			break;
+		case PCA9532_TYPE_LED:
+			led->state = pled->state;
+			led->name =  pled->name;
+			led->ldev.name = led->name;
+			led->ldev.brightness = LED_OFF;
+			led->ldev.brightness_set = pca9532_set_brightness;
+			led->ldev.blink_set = pca9532_set_blink;
+			if (led_classdev_register(&client->dev,
+				&led->ldev) < 0)	{
+				dev_err(&client->dev,
+					"couldn't register LED %s\n",
+					led->name);
+				goto exit;
+			}
+			pca9532_setled(led);
+			break;
+		case PCA9532_TYPE_N2100_BEEP:
+			BUG_ON(data->idev);
+			led->state = PCA9532_PWM1;
+			pca9532_setled(led);
+			data->idev = input_allocate_device();
+			if (data->idev == NULL) {
+				err = -ENOMEM;
+				goto exit;
+			}
+			data->idev->name = pled->name;
+			data->idev->phys = "i2c/pca9532";
+			data->idev->id.bustype = BUS_HOST;
+			data->idev->id.vendor  = 0x001f;
+			data->idev->id.product = 0x0001;
+			data->idev->id.version = 0x0100;
+			data->idev->evbit[0] = BIT_MASK(EV_SND);
+			data->idev->sndbit[0] = BIT_MASK(SND_BELL) |
+						BIT_MASK(SND_TONE);
+			data->idev->event = pca9532_event;
+			input_set_drvdata(data->idev, data);
+			err = input_register_device(data->idev);
+			if (err) {
+				input_free_device(data->idev);
+				data->idev = NULL;
+				goto exit;
+			}
+			break;
+		}
+	}
+	return 0;
+
+exit:
+	if (i > 0)
+		for (i = i - 1; i >= 0; i--)
+			switch (data->leds[i].type) {
+			case PCA9532_TYPE_NONE:
+				break;
+			case PCA9532_TYPE_LED:
+				led_classdev_unregister(&data->leds[i].ldev);
+				break;
+			case PCA9532_TYPE_N2100_BEEP:
+				if (data->idev != NULL) {
+					input_unregister_device(data->idev);
+					input_free_device(data->idev);
+					data->idev = NULL;
+				}
+				break;
+			}
+
+	return err;
+
+}
+
+static int pca9532_probe(struct i2c_client *client,
+	const struct i2c_device_id *id)
+{
+	struct pca9532_data *data = i2c_get_clientdata(client);
+	struct pca9532_platform_data *pca9532_pdata = client->dev.platform_data;
+
+	if (!i2c_check_functionality(client->adapter,
+		I2C_FUNC_SMBUS_BYTE_DATA))
+		return -EIO;
+
+	data = kzalloc(sizeof(struct pca9532_data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	dev_info(&client->dev, "setting platform data\n");
+	i2c_set_clientdata(client, data);
+	data->client = client;
+	mutex_init(&data->update_lock);
+
+	if (pca9532_pdata == NULL)
+		return -EIO;
+
+	pca9532_configure(client, data, pca9532_pdata);
+	return 0;
+
+}
+
+static int pca9532_remove(struct i2c_client *client)
+{
+	struct pca9532_data *data = i2c_get_clientdata(client);
+	int i;
+	for (i = 0; i < 16; i++)
+		switch (data->leds[i].type) {
+		case PCA9532_TYPE_NONE:
+			break;
+		case PCA9532_TYPE_LED:
+			led_classdev_unregister(&data->leds[i].ldev);
+			break;
+		case PCA9532_TYPE_N2100_BEEP:
+			if (data->idev != NULL) {
+				input_unregister_device(data->idev);
+				input_free_device(data->idev);
+				data->idev = NULL;
+			}
+			break;
+		}
+
+	kfree(data);
+	i2c_set_clientdata(client, NULL);
+	return 0;
+}
+
+static int __init pca9532_init(void)
+{
+	return i2c_add_driver(&pca9532_driver);
+}
+
+static void __exit pca9532_exit(void)
+{
+	i2c_del_driver(&pca9532_driver);
+}
+
+MODULE_AUTHOR("Riku Voipio <riku.voipio@movial.fi>");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("PCA 9532 LED dimmer");
+
+module_init(pca9532_init);
+module_exit(pca9532_exit);
+

drivers/leds/leds-pca955x.c

+/*
+ * Copyright 2007-2008 Extreme Engineering Solutions, Inc.
+ *
+ * Author: Nate Case <ncase@xes-inc.com>
+ *
+ * This file is subject to the terms and conditions of version 2 of
+ * the GNU General Public License.  See the file COPYING in the main
+ * directory of this archive for more details.
+ *
+ * LED driver for various PCA955x I2C LED drivers
+ *
+ * Supported devices:
+ *
+ *	Device		Description		7-bit slave address
+ *	------		-----------		-------------------
+ *	PCA9550		2-bit driver		0x60 .. 0x61
+ *	PCA9551		8-bit driver		0x60 .. 0x67
+ *	PCA9552		16-bit driver		0x60 .. 0x67
+ *	PCA9553/01	4-bit driver		0x62
+ *	PCA9553/02	4-bit driver		0x63
+ *
+ * Philips PCA955x LED driver chips follow a register map as shown below:
+ *
+ *	Control Register		Description
+ *	----------------		-----------
+ *	0x0				Input register 0
+ *					..
+ *	NUM_INPUT_REGS - 1		Last Input register X
+ *
+ *	NUM_INPUT_REGS			Frequency prescaler 0
+ *	NUM_INPUT_REGS + 1		PWM register 0
+ *	NUM_INPUT_REGS + 2		Frequency prescaler 1
+ *	NUM_INPUT_REGS + 3		PWM register 1
+ *
+ *	NUM_INPUT_REGS + 4		LED selector 0
+ *	NUM_INPUT_REGS + 4
+ *	    + NUM_LED_REGS - 1		Last LED selector
+ *
+ *  where NUM_INPUT_REGS and NUM_LED_REGS vary depending on how many
+ *  bits the chip supports.
+ */
+
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/string.h>
+#include <linux/ctype.h>
+#include <linux/leds.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/workqueue.h>
+
+/* LED select registers determine the source that drives LED outputs */
+#define PCA955X_LS_LED_ON	0x0	/* Output LOW */
+#define PCA955X_LS_LED_OFF	0x1	/* Output HI-Z */
+#define PCA955X_LS_BLINK0	0x2	/* Blink at PWM0 rate */
+#define PCA955X_LS_BLINK1	0x3	/* Blink at PWM1 rate */
+
+enum pca955x_type {
+	pca9550,
+	pca9551,
+	pca9552,
+	pca9553,
+};
+
+struct pca955x_chipdef {
+	int			bits;
+	u8			slv_addr;	/* 7-bit slave address mask */
+	int			slv_addr_shift;	/* Number of bits to ignore */
+};
+
+static struct pca955x_chipdef pca955x_chipdefs[] = {
+	[pca9550] = {
+		.bits		= 2,
+		.slv_addr	= /* 110000x */ 0x60,
+		.slv_addr_shift	= 1,
+	},
+	[pca9551] = {
+		.bits		= 8,
+		.slv_addr	= /* 1100xxx */ 0x60,
+		.slv_addr_shift	= 3,
+	},
+	[pca9552] = {
+		.bits		= 16,
+		.slv_addr	= /* 1100xxx */ 0x60,
+		.slv_addr_shift	= 3,
+	},
+	[pca9553] = {
+		.bits		= 4,
+		.slv_addr	= /* 110001x */ 0x62,
+		.slv_addr_shift	= 1,
+	},
+};
+
+static const struct i2c_device_id pca955x_id[] = {
+	{ "pca9550", pca9550 },
+	{ "pca9551", pca9551 },
+	{ "pca9552", pca9552 },
+	{ "pca9553", pca9553 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, pca955x_id);
+
+struct pca955x_led {
+	struct pca955x_chipdef	*chipdef;
+	struct i2c_client	*client;
+	struct work_struct	work;
+	spinlock_t		lock;
+	enum led_brightness	brightness;
+	struct led_classdev	led_cdev;
+	int			led_num;	/* 0 .. 15 potentially */
+	char			name[32];
+};
+
+/* 8 bits per input register */
+static inline int pca95xx_num_input_regs(int bits)
+{
+	return (bits + 7) / 8;
+}
+
+/* 4 bits per LED selector register */
+static inline int pca95xx_num_led_regs(int bits)
+{
+	return (bits + 3)  / 4;
+}
+
+/*
+ * Return an LED selector register value based on an existing one, with
+ * the appropriate 2-bit state value set for the given LED number (0-3).
+ */
+static inline u8 pca955x_ledsel(u8 oldval, int led_num, int state)
+{
+	return (oldval & (~(0x3 << (led_num << 1)))) |
+		((state & 0x3) << (led_num << 1));
+}
+
+/*
+ * Write to frequency prescaler register, used to program the
+ * period of the PWM output.  period = (PSCx + 1) / 38
+ */
+static void pca955x_write_psc(struct i2c_client *client, int n, u8 val)
+{
+	struct pca955x_led *pca955x = i2c_get_clientdata(client);
+
+	i2c_smbus_write_byte_data(client,
+		pca95xx_num_input_regs(pca955x->chipdef->bits) + 2*n,
+		val);
+}
+
+/*
+ * Write to PWM register, which determines the duty cycle of the
+ * output.  LED is OFF when the count is less than the value of this
+ * register, and ON when it is greater.  If PWMx == 0, LED is always OFF.
+ *
+ * Duty cycle is (256 - PWMx) / 256
+ */
+static void pca955x_write_pwm(struct i2c_client *client, int n, u8 val)
+{
+	struct pca955x_led *pca955x = i2c_get_clientdata(client);
+
+	i2c_smbus_write_byte_data(client,
+		pca95xx_num_input_regs(pca955x->chipdef->bits) + 1 + 2*n,
+		val);
+}
+
+/*
+ * Write to LED selector register, which determines the source that
+ * drives the LED output.
+ */
+static void pca955x_write_ls(struct i2c_client *client, int n, u8 val)
+{
+	struct pca955x_led *pca955x = i2c_get_clientdata(client);
+
+	i2c_smbus_write_byte_data(client,
+		pca95xx_num_input_regs(pca955x->chipdef->bits) + 4 + n,
+		val);
+}
+
+/*
+ * Read the LED selector register, which determines the source that
+ * drives the LED output.
+ */
+static u8 pca955x_read_ls(struct i2c_client *client, int n)
+{
+	struct pca955x_led *pca955x = i2c_get_clientdata(client);
+
+	return (u8) i2c_smbus_read_byte_data(client,
+		pca95xx_num_input_regs(pca955x->chipdef->bits) + 4 + n);
+}
+
+static void pca955x_led_work(struct work_struct *work)
+{
+	struct pca955x_led *pca955x;
+	u8 ls;
+	int chip_ls;	/* which LSx to use (0-3 potentially) */
+	int ls_led;	/* which set of bits within LSx to use (0-3) */
+
+	pca955x = container_of(work, struct pca955x_led, work);
+	chip_ls = pca955x->led_num / 4;
+	ls_led = pca955x->led_num % 4;
+
+	ls = pca955x_read_ls(pca955x->client, chip_ls);
+
+	switch (pca955x->brightness) {
+	case LED_FULL:
+		ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_LED_ON);
+		break;
+	case LED_OFF:
+		ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_LED_OFF);
+		break;
+	case LED_HALF:
+		ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_BLINK0);
+		break;
+	default:
+		/*
+		 * Use PWM1 for all other values.  This has the unwanted
+		 * side effect of making all LEDs on the chip share the
+		 * same brightness level if set to a value other than
+		 * OFF, HALF, or FULL.  But, this is probably better than
+		 * just turning off for all other values.
+		 */
+		pca955x_write_pwm(pca955x->client, 1, 255-pca955x->brightness);
+		ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_BLINK1);
+		break;
+	}
+
+	pca955x_write_ls(pca955x->client, chip_ls, ls);
+}
+
+void pca955x_led_set(struct led_classdev *led_cdev, enum led_brightness value)
+{
+	struct pca955x_led *pca955x;
+
+	pca955x = container_of(led_cdev, struct pca955x_led, led_cdev);
+
+	spin_lock(&pca955x->lock);
+	pca955x->brightness = value;
+
+	/*
+	 * Must use workqueue for the actual I/O since I2C operations
+	 * can sleep.
+	 */
+	schedule_work(&pca955x->work);
+
+	spin_unlock(&pca955x->lock);
+}
+
+static int __devinit pca955x_probe(struct i2c_client *client,
+					const struct i2c_device_id *id)
+{
+	struct pca955x_led *pca955x;
+	int i;
+	int err = -ENODEV;
+	struct pca955x_chipdef *chip;
+	struct i2c_adapter *adapter;
+	struct led_platform_data *pdata;
+
+	chip = &pca955x_chipdefs[id->driver_data];
+	adapter = to_i2c_adapter(client->dev.parent);
+	pdata = client->dev.platform_data;
+
+	/* Make sure the slave address / chip type combo given is possible */
+	if ((client->addr & ~((1 << chip->slv_addr_shift) - 1)) !=
+	    chip->slv_addr) {
+		dev_err(&client->dev, "invalid slave address %02x\n",
+				client->addr);
+		return -ENODEV;
+	}
+
+	printk(KERN_INFO "leds-pca955x: Using %s %d-bit LED driver at "
+			"slave address 0x%02x\n",
+			id->name, chip->bits, client->addr);
+
+	if (!i2c_check_functionality(adapter, I2C_FUNC_I2C))
+		return -EIO;
+
+	if (pdata) {
+		if (pdata->num_leds != chip->bits) {
+			dev_err(&client->dev, "board info claims %d LEDs"
+					" on a %d-bit chip\n",
+					pdata->num_leds, chip->bits);
+			return -ENODEV;
+		}
+	}
+
+	for (i = 0; i < chip->bits; i++) {
+		pca955x = kzalloc(sizeof(struct pca955x_led), GFP_KERNEL);
+		if (!pca955x) {
+			err = -ENOMEM;
+			goto exit;
+		}
+
+		pca955x->chipdef = chip;
+		pca955x->client = client;
+		pca955x->led_num = i;
+		/* Platform data can specify LED names and default triggers */
+		if (pdata) {
+			if (pdata->leds[i].name)
+				snprintf(pca955x->name, 32, "pca955x:%s",
+							pdata->leds[i].name);
+			if (pdata->leds[i].default_trigger)
+				pca955x->led_cdev.default_trigger =
+					pdata->leds[i].default_trigger;
+		} else {
+			snprintf(pca955x->name, 32, "pca955x:%d", i);
+		}
+		spin_lock_init(&pca955x->lock);
+
+		pca955x->led_cdev.name = pca955x->name;
+		pca955x->led_cdev.brightness_set =
+				pca955x_led_set;
+
+		/*
+		 * Client data is a pointer to the _first_ pca955x_led
+		 * struct
+		 */
+		if (i == 0)
+			i2c_set_clientdata(client, pca955x);
+
+		INIT_WORK(&(pca955x->work), pca955x_led_work);
+
+		led_classdev_register(&client->dev, &(pca955x->led_cdev));
+	}
+
+	/* Turn off LEDs */
+	for (i = 0; i < pca95xx_num_led_regs(chip->bits); i++)
+		pca955x_write_ls(client, i, 0x55);
+
+	/* PWM0 is used for half brightness or 50% duty cycle */
+	pca955x_write_pwm(client, 0, 255-LED_HALF);
+
+	/* PWM1 is used for variable brightness, default to OFF */
+	pca955x_write_pwm(client, 1, 0);
+
+	/* Set to fast frequency so we do not see flashing */
+	pca955x_write_psc(client, 0, 0);
+	pca955x_write_psc(client, 1, 0);
+
+	return 0;
+exit:
+	return err;
+}
+
+static int __devexit pca955x_remove(struct i2c_client *client)
+{
+	struct pca955x_led *pca955x = i2c_get_clientdata(client);
+	int leds = pca955x->chipdef->bits;
+	int i;
+
+	for (i = 0; i < leds; i++) {
+		led_classdev_unregister(&(pca955x->led_cdev));
+		cancel_work_sync(&(pca955x->work));
+		kfree(pca955x);
+		pca955x = pca955x + 1;
+	}
+
+	return 0;
+}
+
+static struct i2c_driver pca955x_driver = {
+	.driver = {
+		.name	= "leds-pca955x",
+		.owner	= THIS_MODULE,
+	},
+	.probe	= pca955x_probe,
+	.remove	= __devexit_p(pca955x_remove),
+	.id_table = pca955x_id,
+};
+
+static int __init pca955x_leds_init(void)
+{
+	return i2c_add_driver(&pca955x_driver);
+}
+
+static void __exit pca955x_leds_exit(void)
+{
+	i2c_del_driver(&pca955x_driver);
+}
+
+module_init(pca955x_leds_init);
+module_exit(pca955x_leds_exit);
+
+MODULE_AUTHOR("Nate Case <ncase@xes-inc.com>");
+MODULE_DESCRIPTION("PCA955x LED driver");
+MODULE_LICENSE("GPL v2");

include/linux/leds-pca9532.h

+/*
+ * pca9532.h - platform data structure for pca9532 led controller
+ *
+ * Copyright (C) 2008 Riku Voipio <riku.voipio@movial.fi>
+ *
+ * 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; version 2 of the License.
+ *
+ * Datasheet: http://www.nxp.com/acrobat/datasheets/PCA9532_3.pdf
+ *
+ */
+
+#ifndef __LINUX_PCA9532_H
+#define __LINUX_PCA9532_H
+
+#include <linux/leds.h>
+
+enum pca9532_state {
+	PCA9532_OFF  = 0x0,
+	PCA9532_ON   = 0x1,
+	PCA9532_PWM0 = 0x2,
+	PCA9532_PWM1 = 0x3
+};
+
+enum pca9532_type { PCA9532_TYPE_NONE, PCA9532_TYPE_LED,
+	PCA9532_TYPE_N2100_BEEP };
+
+struct pca9532_led {
+	u8 id;
+	struct i2c_client *client;
+	char *name;
+	struct led_classdev ldev;
+	enum pca9532_type type;
+	enum pca9532_state state;
+};
+
+struct pca9532_platform_data {
+	struct pca9532_led leds[16];
+	u8 pwm[2];
+	u8 psc[2];
+};
+
+#endif /* __LINUX_PCA9532_H */
+

include/linux/leds.h

@@ -48,7 +48,7 @@ struct led_classdev {
 
 	struct device		*dev;
 	struct list_head	 node;			/* LED Device list */
-	char			*default_trigger;	/* Trigger to use */
+	const char		*default_trigger;	/* Trigger to use */
 
 #ifdef CONFIG_LEDS_TRIGGERS
 	/* Protects the trigger data below */
@@ -118,6 +118,20 @@ extern void ledtrig_ide_activity(void);
 #define ledtrig_ide_activity() do {} while(0)
 #endif
 
+/*
+ * Generic LED platform data for describing LED names and default triggers.
+ */
+struct led_info {
+	const char	*name;
+	char		*default_trigger;
+	int		flags;
+};
+
+struct led_platform_data {
+	int		num_leds;
+	struct led_info	*leds;
+};
+
 /* For the leds-gpio driver */
 struct gpio_led {
 	const char *name;