Commit 0081e802 authored by Mark Brown's avatar Mark Brown Committed by Richard Purdie
Browse files

leds: Add WM8350 LED driver 



The voltage and current regulators on the WM8350 AudioPlus PMIC can be
used in concert to provide a power efficient LED driver.  This driver
implements support for this within the standard LED class.

Platform initialisation code should configure the LED hardware in the
init callback provided by the WM8350 core driver.  The callback should
use wm8350_isink_set_flash(), wm8350_dcdc25_set_mode() and
wm8350_dcdc_set_slot() to configure the operating parameters of the
regulators for their hardware and then then use wm8350_register_led() to
instantiate the LED driver.

This driver was originally written by Liam Girdwood, though it has been
extensively modified since then.

Signed-off-by: default avatarMark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: default avatarRichard Purdie <rpurdie@linux.intel.com>
parent 934cd3f9

drivers/leds/Kconfig

+7 −0
Original line number Diff line number Diff line
@@ -164,6 +164,13 @@ config LEDS_PCA955X 
	  LED driver chips accessed via the I2C bus.  Supported

	  devices include PCA9550, PCA9551, PCA9552, and PCA9553.



config LEDS_WM8350

	tristate "LED Support for WM8350 AudioPlus PMIC"

	depends on LEDS_CLASS && MFD_WM8350

	help

	  This option enables support for LEDs driven by the Wolfson

	  Microelectronics WM8350 AudioPlus PMIC.



config LEDS_DA903X

	tristate "LED Support for DA9030/DA9034 PMIC"

	depends on LEDS_CLASS && PMIC_DA903X

drivers/leds/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -24,6 +24,7 @@ obj-$(CONFIG_LEDS_FSG) += leds-fsg.o 
obj-$(CONFIG_LEDS_PCA955X)		+= leds-pca955x.o

obj-$(CONFIG_LEDS_DA903X)		+= leds-da903x.o

obj-$(CONFIG_LEDS_HP_DISK)		+= leds-hp-disk.o

obj-$(CONFIG_LEDS_WM8350)		+= leds-wm8350.o



# LED Triggers

obj-$(CONFIG_LEDS_TRIGGER_TIMER)	+= ledtrig-timer.o

drivers/leds/leds-wm8350.c

0 → 100644
+333 −0
Original line number Diff line number Diff line 
/*

 * LED driver for WM8350 driven LEDS.

 *

 * Copyright(C) 2007, 2008 Wolfson Microelectronics PLC.

 *

 * 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.

 *

 */



#include <linux/kernel.h>

#include <linux/init.h>

#include <linux/platform_device.h>

#include <linux/leds.h>

#include <linux/err.h>

#include <linux/mfd/wm8350/pmic.h>

#include <linux/regulator/consumer.h>



/* Microamps */

static const int isink_cur[] = {

	4,

	5,

	6,

	7,

	8,

	10,

	11,

	14,

	16,

	19,

	23,

	27,

	32,

	39,

	46,

	54,

	65,

	77,

	92,

	109,

	130,

	154,

	183,

	218,

	259,

	308,

	367,

	436,

	518,

	616,

	733,

	872,

	1037,

	1233,

	1466,

	1744,

	2073,

	2466,

	2933,

	3487,

	4147,

	4932,

	5865,

	6975,

	8294,

	9864,

	11730,

	13949,

	16589,

	19728,

	23460,

	27899,

	33178,

	39455,

	46920,

	55798,

	66355,

	78910,

	93840,

	111596,

	132710,

	157820,

	187681,

	223191

};



#define to_wm8350_led(led_cdev) \

	container_of(led_cdev, struct wm8350_led, cdev)



static void wm8350_led_enable(struct wm8350_led *led)

{

	int ret;



	if (led->enabled)

		return;



	ret = regulator_enable(led->isink);

	if (ret != 0) {

		dev_err(led->cdev.dev, "Failed to enable ISINK: %d\n", ret);

		return;

	}



	ret = regulator_enable(led->dcdc);

	if (ret != 0) {

		dev_err(led->cdev.dev, "Failed to enable DCDC: %d\n", ret);

		regulator_disable(led->isink);

		return;

	}



	led->enabled = 1;

}



static void wm8350_led_disable(struct wm8350_led *led)

{

	int ret;



	if (!led->enabled)

		return;



	ret = regulator_disable(led->dcdc);

	if (ret != 0) {

		dev_err(led->cdev.dev, "Failed to disable DCDC: %d\n", ret);

		return;

	}



	ret = regulator_disable(led->isink);

	if (ret != 0) {

		dev_err(led->cdev.dev, "Failed to disable ISINK: %d\n", ret);

		regulator_enable(led->dcdc);

		return;

	}



	led->enabled = 0;

}



static void led_work(struct work_struct *work)

{

	struct wm8350_led *led = container_of(work, struct wm8350_led, work);

	int ret;

	int uA;

	unsigned long flags;



	mutex_lock(&led->mutex);



	spin_lock_irqsave(&led->value_lock, flags);



	if (led->value == LED_OFF) {

		spin_unlock_irqrestore(&led->value_lock, flags);

		wm8350_led_disable(led);

		goto out;

	}



	/* This scales linearly into the index of valid current

	 * settings which results in a linear scaling of perceived

	 * brightness due to the non-linear current settings provided

	 * by the hardware.

	 */

	uA = (led->max_uA_index * led->value) / LED_FULL;

	spin_unlock_irqrestore(&led->value_lock, flags);

	BUG_ON(uA >= ARRAY_SIZE(isink_cur));



	ret = regulator_set_current_limit(led->isink, isink_cur[uA],

					  isink_cur[uA]);

	if (ret != 0)

		dev_err(led->cdev.dev, "Failed to set %duA: %d\n",

			isink_cur[uA], ret);



	wm8350_led_enable(led);



out:

	mutex_unlock(&led->mutex);

}



static void wm8350_led_set(struct led_classdev *led_cdev,

			   enum led_brightness value)

{

	struct wm8350_led *led = to_wm8350_led(led_cdev);

	unsigned long flags;



	spin_lock_irqsave(&led->value_lock, flags);

	led->value = value;

	schedule_work(&led->work);

	spin_unlock_irqrestore(&led->value_lock, flags);

}



#ifdef CONFIG_PM

static int wm8350_led_suspend(struct platform_device *pdev, pm_message_t state)

{

	struct wm8350_led *led = platform_get_drvdata(pdev);



	led_classdev_suspend(&led->cdev);

	return 0;

}



static int wm8350_led_resume(struct platform_device *pdev)

{

	struct wm8350_led *led = platform_get_drvdata(pdev);



	led_classdev_resume(&led->cdev);

	return 0;

}

#else

#define wm8350_led_suspend NULL

#define wm8350_led_resume NULL

#endif



static void wm8350_led_shutdown(struct platform_device *pdev)

{

	struct wm8350_led *led = platform_get_drvdata(pdev);



	mutex_lock(&led->mutex);

	led->value = LED_OFF;

	wm8350_led_disable(led);

	mutex_unlock(&led->mutex);

}



static int wm8350_led_probe(struct platform_device *pdev)

{

	struct regulator *isink, *dcdc;

	struct wm8350_led *led;

	struct wm8350_led_platform_data *pdata = pdev->dev.platform_data;

	int ret, i;



	if (pdata == NULL) {

		dev_err(&pdev->dev, "no platform data\n");

		return -ENODEV;

	}



	if (pdata->max_uA < isink_cur[0]) {

		dev_err(&pdev->dev, "Invalid maximum current %duA\n",

			pdata->max_uA);

		return -EINVAL;

	}



	isink = regulator_get(&pdev->dev, "led_isink");

	if (IS_ERR(isink)) {

		printk(KERN_ERR "%s: cant get ISINK\n", __func__);

		return PTR_ERR(isink);

	}



	dcdc = regulator_get(&pdev->dev, "led_vcc");

	if (IS_ERR(dcdc)) {

		printk(KERN_ERR "%s: cant get DCDC\n", __func__);

		ret = PTR_ERR(dcdc);

		goto err_isink;

	}



	led = kzalloc(sizeof(*led), GFP_KERNEL);

	if (led == NULL) {

		ret = -ENOMEM;

		goto err_dcdc;

	}



	led->cdev.brightness_set = wm8350_led_set;

	led->cdev.default_trigger = pdata->default_trigger;

	led->cdev.name = pdata->name;

	led->enabled = regulator_is_enabled(isink);

	led->isink = isink;

	led->dcdc = dcdc;



	for (i = 0; i < ARRAY_SIZE(isink_cur) - 1; i++)

		if (isink_cur[i] >= pdata->max_uA)

			break;

	led->max_uA_index = i;

	if (pdata->max_uA != isink_cur[i])

		dev_warn(&pdev->dev,

			 "Maximum current %duA is not directly supported,"

			 " check platform data\n",

			 pdata->max_uA);



	spin_lock_init(&led->value_lock);

	mutex_init(&led->mutex);

	INIT_WORK(&led->work, led_work);

	led->value = LED_OFF;

	platform_set_drvdata(pdev, led);



	ret = led_classdev_register(&pdev->dev, &led->cdev);

	if (ret < 0)

		goto err_led;



	return 0;



 err_led:

	kfree(led);

 err_dcdc:

	regulator_put(dcdc);

 err_isink:

	regulator_put(isink);

	return ret;

}



static int wm8350_led_remove(struct platform_device *pdev)

{

	struct wm8350_led *led = platform_get_drvdata(pdev);



	led_classdev_unregister(&led->cdev);

	flush_scheduled_work();

	wm8350_led_disable(led);

	regulator_put(led->dcdc);

	regulator_put(led->isink);

	kfree(led);

	return 0;

}



static struct platform_driver wm8350_led_driver = {

	.driver = {

		   .name = "wm8350-led",

		   .owner = THIS_MODULE,

		   },

	.probe = wm8350_led_probe,

	.remove = wm8350_led_remove,

	.shutdown = wm8350_led_shutdown,

	.suspend = wm8350_led_suspend,

	.resume = wm8350_led_resume,

};



static int __devinit wm8350_led_init(void)

{

	return platform_driver_register(&wm8350_led_driver);

}

module_init(wm8350_led_init);



static void wm8350_led_exit(void)

{

	platform_driver_unregister(&wm8350_led_driver);

}

module_exit(wm8350_led_exit);



MODULE_AUTHOR("Mark Brown");

MODULE_DESCRIPTION("WM8350 LED driver");

MODULE_LICENSE("GPL");

MODULE_ALIAS("platform:wm8350-led");

drivers/mfd/wm8350-core.c

+3 −0
Original line number Diff line number Diff line
@@ -1453,6 +1453,9 @@ void wm8350_device_exit(struct wm8350 *wm8350) 
{

	int i;



	for (i = 0; i < ARRAY_SIZE(wm8350->pmic.led); i++)

		platform_device_unregister(wm8350->pmic.led[i].pdev);



	for (i = 0; i < ARRAY_SIZE(wm8350->pmic.pdev); i++)

		platform_device_unregister(wm8350->pmic.pdev[i]);

drivers/regulator/wm8350-regulator.c

+91 −0
Original line number Diff line number Diff line
@@ -1412,6 +1412,97 @@ int wm8350_register_regulator(struct wm8350 *wm8350, int reg, 
}

EXPORT_SYMBOL_GPL(wm8350_register_regulator);



/**

 * wm8350_register_led - Register a WM8350 LED output

 *

 * @param wm8350 The WM8350 device to configure.

 * @param lednum LED device index to create.

 * @param dcdc The DCDC to use for the LED.

 * @param isink The ISINK to use for the LED.

 * @param pdata Configuration for the LED.

 *

 * The WM8350 supports the use of an ISINK together with a DCDC to

 * provide a power-efficient LED driver.  This function registers the

 * regulators and instantiates the platform device for a LED.  The

 * operating modes for the LED regulators must be configured using

 * wm8350_isink_set_flash(), wm8350_dcdc25_set_mode() and

 * wm8350_dcdc_set_slot() prior to calling this function.

 */

int wm8350_register_led(struct wm8350 *wm8350, int lednum, int dcdc, int isink,

			struct wm8350_led_platform_data *pdata)

{

	struct wm8350_led *led;

	struct platform_device *pdev;

	int ret;



	if (lednum > ARRAY_SIZE(wm8350->pmic.led) || lednum < 0) {

		dev_err(wm8350->dev, "Invalid LED index %d\n", lednum);

		return -ENODEV;

	}



	led = &wm8350->pmic.led[lednum];



	if (led->pdev) {

		dev_err(wm8350->dev, "LED %d already allocated\n", lednum);

		return -EINVAL;

	}



	pdev = platform_device_alloc("wm8350-led", lednum);

	if (pdev == NULL) {

		dev_err(wm8350->dev, "Failed to allocate LED %d\n", lednum);

		return -ENOMEM;

	}



	led->isink_consumer.dev = &pdev->dev;

	led->isink_consumer.supply = "led_isink";

	led->isink_init.num_consumer_supplies = 1;

	led->isink_init.consumer_supplies = &led->isink_consumer;

	led->isink_init.constraints.min_uA = 0;

	led->isink_init.constraints.max_uA = pdata->max_uA;

	led->isink_init.constraints.valid_ops_mask = REGULATOR_CHANGE_CURRENT;

	led->isink_init.constraints.valid_modes_mask = REGULATOR_MODE_NORMAL;

	ret = wm8350_register_regulator(wm8350, isink, &led->isink_init);

	if (ret != 0) {

		platform_device_put(pdev);

		return ret;

	}



	led->dcdc_consumer.dev = &pdev->dev;

	led->dcdc_consumer.supply = "led_vcc";

	led->dcdc_init.num_consumer_supplies = 1;

	led->dcdc_init.consumer_supplies = &led->dcdc_consumer;

	led->dcdc_init.constraints.valid_modes_mask = REGULATOR_MODE_NORMAL;

	ret = wm8350_register_regulator(wm8350, dcdc, &led->dcdc_init);

	if (ret != 0) {

		platform_device_put(pdev);

		return ret;

	}



	switch (isink) {

	case WM8350_ISINK_A:

		wm8350->pmic.isink_A_dcdc = dcdc;

		break;

	case WM8350_ISINK_B:

		wm8350->pmic.isink_B_dcdc = dcdc;

		break;

	}



	pdev->dev.platform_data = pdata;

	pdev->dev.parent = wm8350->dev;

	ret = platform_device_add(pdev);

	if (ret != 0) {

		dev_err(wm8350->dev, "Failed to register LED %d: %d\n",

			lednum, ret);

		platform_device_put(pdev);

		return ret;

	}



	led->pdev = pdev;



	return 0;

}

EXPORT_SYMBOL_GPL(wm8350_register_led);



static struct platform_driver wm8350_regulator_driver = {

	.probe = wm8350_regulator_probe,

	.remove = wm8350_regulator_remove,

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