drivers/leds/leds-ns2.c - linux - Git at Google

 /*
  * leds-ns2.c - Driver for the Network Space v2 (and parents) dual-GPIO LED
  *
  * Copyright (C) 2010 LaCie
  *
  * Author: Simon Guinot <sguinot@lacie.com>
  *
  * Based on leds-gpio.c by Raphael Assenat <raph@8d.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/kernel.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <linux/gpio.h>
 #include <linux/leds.h>
 #include <linux/module.h>
 #include <linux/platform_data/leds-kirkwood-ns2.h>
 #include <linux/of.h>
 #include <linux/of_gpio.h>

 /*
  * The Network Space v2 dual-GPIO LED is wired to a CPLD and can blink in
  * relation with the SATA activity. This capability is exposed through the
  * "sata" sysfs attribute.
  *
  * The following array detail the different LED registers and the combination
  * of their possible values:
  *
  *  cmd_led   |  slow_led  | /SATA active | LED state
  *            |            |              |
  *     1      |     0      |      x       |  off
  *     -      |     1      |      x       |  on
  *     0      |     0      |      1       |  on
  *     0      |     0      |      0       |  blink (rate 300ms)
  */

 enum ns2_led_modes {
 	NS_V2_LED_OFF,
 	NS_V2_LED_ON,
 	NS_V2_LED_SATA,
 };

 struct ns2_led_mode_value {
 	enum ns2_led_modes	mode;
 	int			cmd_level;
 	int			slow_level;
 };

 static struct ns2_led_mode_value ns2_led_modval[] = {
 	{ NS_V2_LED_OFF	, 1, 0 },
 	{ NS_V2_LED_ON	, 0, 1 },
 	{ NS_V2_LED_ON	, 1, 1 },
 	{ NS_V2_LED_SATA, 0, 0 },
 };

 struct ns2_led_data {
 	struct led_classdev	cdev;
 	unsigned		cmd;
 	unsigned		slow;
 	unsigned char		sata; /* True when SATA mode active. */
 	rwlock_t		rw_lock; /* Lock GPIOs. */
 };

 static int ns2_led_get_mode(struct ns2_led_data *led_dat,
 			    enum ns2_led_modes *mode)
 {
 	int i;
 	int ret = -EINVAL;
 	int cmd_level;
 	int slow_level;

 	read_lock_irq(&led_dat->rw_lock);

 	cmd_level = gpio_get_value(led_dat->cmd);
 	slow_level = gpio_get_value(led_dat->slow);

 	for (i = 0; i < ARRAY_SIZE(ns2_led_modval); i++) {
 		if (cmd_level == ns2_led_modval[i].cmd_level &&
 		    slow_level == ns2_led_modval[i].slow_level) {
 			*mode = ns2_led_modval[i].mode;
 			ret = 0;
 			break;
 		}
 	}

 	read_unlock_irq(&led_dat->rw_lock);

 	return ret;
 }

 static void ns2_led_set_mode(struct ns2_led_data *led_dat,
 			     enum ns2_led_modes mode)
 {
 	int i;
 	unsigned long flags;

 	write_lock_irqsave(&led_dat->rw_lock, flags);

 	for (i = 0; i < ARRAY_SIZE(ns2_led_modval); i++) {
 		if (mode == ns2_led_modval[i].mode) {
 			gpio_set_value(led_dat->cmd,
 				       ns2_led_modval[i].cmd_level);
 			gpio_set_value(led_dat->slow,
 				       ns2_led_modval[i].slow_level);
 		}
 	}

 	write_unlock_irqrestore(&led_dat->rw_lock, flags);
 }

 static void ns2_led_set(struct led_classdev *led_cdev,
 			enum led_brightness value)
 {
 	struct ns2_led_data *led_dat =
 		container_of(led_cdev, struct ns2_led_data, cdev);
 	enum ns2_led_modes mode;

 	if (value == LED_OFF)
 		mode = NS_V2_LED_OFF;
 	else if (led_dat->sata)
 		mode = NS_V2_LED_SATA;
 	else
 		mode = NS_V2_LED_ON;

 	ns2_led_set_mode(led_dat, mode);
 }

 static ssize_t ns2_led_sata_store(struct device *dev,
 				  struct device_attribute *attr,
 				  const char *buff, size_t count)
 {
 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
 	struct ns2_led_data *led_dat =
 		container_of(led_cdev, struct ns2_led_data, cdev);
 	int ret;
 	unsigned long enable;
 	enum ns2_led_modes mode;

 	ret = kstrtoul(buff, 10, &enable);
 	if (ret < 0)
 		return ret;

 	enable = !!enable;

 	if (led_dat->sata == enable)
 		return count;

 	ret = ns2_led_get_mode(led_dat, &mode);
 	if (ret < 0)
 		return ret;

 	if (enable && mode == NS_V2_LED_ON)
 		ns2_led_set_mode(led_dat, NS_V2_LED_SATA);
 	if (!enable && mode == NS_V2_LED_SATA)
 		ns2_led_set_mode(led_dat, NS_V2_LED_ON);

 	led_dat->sata = enable;

 	return count;
 }

 static ssize_t ns2_led_sata_show(struct device *dev,
 				 struct device_attribute *attr, char *buf)
 {
 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
 	struct ns2_led_data *led_dat =
 		container_of(led_cdev, struct ns2_led_data, cdev);

 	return sprintf(buf, "%d\n", led_dat->sata);
 }

 static DEVICE_ATTR(sata, 0644, ns2_led_sata_show, ns2_led_sata_store);

 static struct attribute *ns2_led_attrs[] = {
 	&dev_attr_sata.attr,
 	NULL
 };
 ATTRIBUTE_GROUPS(ns2_led);

 static int
 create_ns2_led(struct platform_device *pdev, struct ns2_led_data *led_dat,
 	       const struct ns2_led *template)
 {
 	int ret;
 	enum ns2_led_modes mode;

 	ret = devm_gpio_request_one(&pdev->dev, template->cmd,
 			gpio_get_value(template->cmd) ?
 			GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW,
 			template->name);
 	if (ret) {
 		dev_err(&pdev->dev, "%s: failed to setup command GPIO\n",
 			template->name);
 		return ret;
 	}

 	ret = devm_gpio_request_one(&pdev->dev, template->slow,
 			gpio_get_value(template->slow) ?
 			GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW,
 			template->name);
 	if (ret) {
 		dev_err(&pdev->dev, "%s: failed to setup slow GPIO\n",
 			template->name);
 		return ret;
 	}

 	rwlock_init(&led_dat->rw_lock);

 	led_dat->cdev.name = template->name;
 	led_dat->cdev.default_trigger = template->default_trigger;
 	led_dat->cdev.blink_set = NULL;
 	led_dat->cdev.brightness_set = ns2_led_set;
 	led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME;
 	led_dat->cdev.groups = ns2_led_groups;
 	led_dat->cmd = template->cmd;
 	led_dat->slow = template->slow;

 	ret = ns2_led_get_mode(led_dat, &mode);
 	if (ret < 0)
 		return ret;

 	/* Set LED initial state. */
 	led_dat->sata = (mode == NS_V2_LED_SATA) ? 1 : 0;
 	led_dat->cdev.brightness =
 		(mode == NS_V2_LED_OFF) ? LED_OFF : LED_FULL;

 	ret = led_classdev_register(&pdev->dev, &led_dat->cdev);
 	if (ret < 0)
 		return ret;

 	return 0;
 }

 static void delete_ns2_led(struct ns2_led_data *led_dat)
 {
 	led_classdev_unregister(&led_dat->cdev);
 }

 #ifdef CONFIG_OF_GPIO
 /*
  * Translate OpenFirmware node properties into platform_data.
  */
 static int
 ns2_leds_get_of_pdata(struct device *dev, struct ns2_led_platform_data *pdata)
 {
 	struct device_node *np = dev->of_node;
 	struct device_node *child;
 	struct ns2_led *leds;
 	int num_leds = 0;
 	int i = 0;

 	num_leds = of_get_child_count(np);
 	if (!num_leds)
 		return -ENODEV;

 	leds = devm_kzalloc(dev, num_leds * sizeof(struct ns2_led),
 			    GFP_KERNEL);
 	if (!leds)
 		return -ENOMEM;

 	for_each_child_of_node(np, child) {
 		const char *string;
 		int ret;

 		ret = of_get_named_gpio(child, "cmd-gpio", 0);
 		if (ret < 0)
 			return ret;
 		leds[i].cmd = ret;
 		ret = of_get_named_gpio(child, "slow-gpio", 0);
 		if (ret < 0)
 			return ret;
 		leds[i].slow = ret;
 		ret = of_property_read_string(child, "label", &string);
 		leds[i].name = (ret == 0) ? string : child->name;
 		ret = of_property_read_string(child, "linux,default-trigger",
 					      &string);
 		if (ret == 0)
 			leds[i].default_trigger = string;

 		i++;
 	}

 	pdata->leds = leds;
 	pdata->num_leds = num_leds;

 	return 0;
 }

 static const struct of_device_id of_ns2_leds_match[] = {
 	{ .compatible = "lacie,ns2-leds", },
 	{},
 };
 #endif /* CONFIG_OF_GPIO */

 struct ns2_led_priv {
 	int num_leds;
 	struct ns2_led_data leds_data[];
 };

 static inline int sizeof_ns2_led_priv(int num_leds)
 {
 	return sizeof(struct ns2_led_priv) +
 		      (sizeof(struct ns2_led_data) * num_leds);
 }

 static int ns2_led_probe(struct platform_device *pdev)
 {
 	struct ns2_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
 	struct ns2_led_priv *priv;
 	int i;
 	int ret;

 #ifdef CONFIG_OF_GPIO
 	if (!pdata) {
 		pdata = devm_kzalloc(&pdev->dev,
 				     sizeof(struct ns2_led_platform_data),
 				     GFP_KERNEL);
 		if (!pdata)
 			return -ENOMEM;

 		ret = ns2_leds_get_of_pdata(&pdev->dev, pdata);
 		if (ret)
 			return ret;
 	}
 #else
 	if (!pdata)
 		return -EINVAL;
 #endif /* CONFIG_OF_GPIO */

 	priv = devm_kzalloc(&pdev->dev,
 			    sizeof_ns2_led_priv(pdata->num_leds), GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;
 	priv->num_leds = pdata->num_leds;

 	for (i = 0; i < priv->num_leds; i++) {
 		ret = create_ns2_led(pdev, &priv->leds_data[i],
 				     &pdata->leds[i]);
 		if (ret < 0) {
 			for (i = i - 1; i >= 0; i--)
 				delete_ns2_led(&priv->leds_data[i]);
 			return ret;
 		}
 	}

 	platform_set_drvdata(pdev, priv);

 	return 0;
 }

 static int ns2_led_remove(struct platform_device *pdev)
 {
 	int i;
 	struct ns2_led_priv *priv;

 	priv = platform_get_drvdata(pdev);

 	for (i = 0; i < priv->num_leds; i++)
 		delete_ns2_led(&priv->leds_data[i]);

 	return 0;
 }

 static struct platform_driver ns2_led_driver = {
 	.probe		= ns2_led_probe,
 	.remove		= ns2_led_remove,
 	.driver		= {
 		.name		= "leds-ns2",
 		.of_match_table	= of_match_ptr(of_ns2_leds_match),
 	},
 };

 module_platform_driver(ns2_led_driver);

 MODULE_AUTHOR("Simon Guinot <sguinot@lacie.com>");
 MODULE_DESCRIPTION("Network Space v2 LED driver");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS("platform:leds-ns2");
	/*
	* leds-ns2.c - Driver for the Network Space v2 (and parents) dual-GPIO LED
	*
	* Copyright (C) 2010 LaCie
	*
	* Author: Simon Guinot <sguinot@lacie.com>
	*
	* Based on leds-gpio.c by Raphael Assenat <raph@8d.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/kernel.h>
	#include <linux/platform_device.h>
	#include <linux/slab.h>
	#include <linux/gpio.h>
	#include <linux/leds.h>
	#include <linux/module.h>
	#include <linux/platform_data/leds-kirkwood-ns2.h>
	#include <linux/of.h>
	#include <linux/of_gpio.h>

	/*
	* The Network Space v2 dual-GPIO LED is wired to a CPLD and can blink in
	* relation with the SATA activity. This capability is exposed through the
	* "sata" sysfs attribute.
	*
	* The following array detail the different LED registers and the combination
	* of their possible values:
	*
	* cmd_led \| slow_led \| /SATA active \| LED state
	* \| \| \|
	* 1 \| 0 \| x \| off
	* - \| 1 \| x \| on
	* 0 \| 0 \| 1 \| on
	* 0 \| 0 \| 0 \| blink (rate 300ms)
	*/

	enum ns2_led_modes {
	NS_V2_LED_OFF,
	NS_V2_LED_ON,
	NS_V2_LED_SATA,
	};

	struct ns2_led_mode_value {
	enum ns2_led_modes mode;
	int cmd_level;
	int slow_level;
	};

	static struct ns2_led_mode_value ns2_led_modval[] = {
	{ NS_V2_LED_OFF , 1, 0 },
	{ NS_V2_LED_ON , 0, 1 },
	{ NS_V2_LED_ON , 1, 1 },
	{ NS_V2_LED_SATA, 0, 0 },
	};

	struct ns2_led_data {
	struct led_classdev cdev;
	unsigned cmd;
	unsigned slow;
	unsigned char sata; /* True when SATA mode active. */
	rwlock_t rw_lock; /* Lock GPIOs. */
	};

	static int ns2_led_get_mode(struct ns2_led_data *led_dat,
	enum ns2_led_modes *mode)
	{
	int i;
	int ret = -EINVAL;
	int cmd_level;
	int slow_level;

	read_lock_irq(&led_dat->rw_lock);

	cmd_level = gpio_get_value(led_dat->cmd);
	slow_level = gpio_get_value(led_dat->slow);

	for (i = 0; i < ARRAY_SIZE(ns2_led_modval); i++) {
	if (cmd_level == ns2_led_modval[i].cmd_level &&
	slow_level == ns2_led_modval[i].slow_level) {
	*mode = ns2_led_modval[i].mode;
	ret = 0;
	break;
	}
	}

	read_unlock_irq(&led_dat->rw_lock);

	return ret;
	}

	static void ns2_led_set_mode(struct ns2_led_data *led_dat,
	enum ns2_led_modes mode)
	{
	int i;
	unsigned long flags;

	write_lock_irqsave(&led_dat->rw_lock, flags);

	for (i = 0; i < ARRAY_SIZE(ns2_led_modval); i++) {
	if (mode == ns2_led_modval[i].mode) {
	gpio_set_value(led_dat->cmd,
	ns2_led_modval[i].cmd_level);
	gpio_set_value(led_dat->slow,
	ns2_led_modval[i].slow_level);
	}
	}

	write_unlock_irqrestore(&led_dat->rw_lock, flags);
	}

	static void ns2_led_set(struct led_classdev *led_cdev,
	enum led_brightness value)
	{
	struct ns2_led_data *led_dat =
	container_of(led_cdev, struct ns2_led_data, cdev);
	enum ns2_led_modes mode;

	if (value == LED_OFF)
	mode = NS_V2_LED_OFF;
	else if (led_dat->sata)
	mode = NS_V2_LED_SATA;
	else
	mode = NS_V2_LED_ON;

	ns2_led_set_mode(led_dat, mode);
	}

	static ssize_t ns2_led_sata_store(struct device *dev,
	struct device_attribute *attr,
	const char *buff, size_t count)
	{
	struct led_classdev *led_cdev = dev_get_drvdata(dev);
	struct ns2_led_data *led_dat =
	container_of(led_cdev, struct ns2_led_data, cdev);
	int ret;
	unsigned long enable;
	enum ns2_led_modes mode;

	ret = kstrtoul(buff, 10, &enable);
	if (ret < 0)
	return ret;

	enable = !!enable;

	if (led_dat->sata == enable)
	return count;

	ret = ns2_led_get_mode(led_dat, &mode);
	if (ret < 0)
	return ret;

	if (enable && mode == NS_V2_LED_ON)
	ns2_led_set_mode(led_dat, NS_V2_LED_SATA);
	if (!enable && mode == NS_V2_LED_SATA)
	ns2_led_set_mode(led_dat, NS_V2_LED_ON);

	led_dat->sata = enable;

	return count;
	}

	static ssize_t ns2_led_sata_show(struct device *dev,
	struct device_attribute attr, char buf)
	{
	struct led_classdev *led_cdev = dev_get_drvdata(dev);
	struct ns2_led_data *led_dat =
	container_of(led_cdev, struct ns2_led_data, cdev);

	return sprintf(buf, "%d\n", led_dat->sata);
	}

	static DEVICE_ATTR(sata, 0644, ns2_led_sata_show, ns2_led_sata_store);

	static struct attribute *ns2_led_attrs[] = {
	&dev_attr_sata.attr,
	NULL
	};
	ATTRIBUTE_GROUPS(ns2_led);

	static int
	create_ns2_led(struct platform_device pdev, struct ns2_led_data led_dat,
	const struct ns2_led *template)
	{
	int ret;
	enum ns2_led_modes mode;

	ret = devm_gpio_request_one(&pdev->dev, template->cmd,
	gpio_get_value(template->cmd) ?
	GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW,
	template->name);
	if (ret) {
	dev_err(&pdev->dev, "%s: failed to setup command GPIO\n",
	template->name);
	return ret;
	}

	ret = devm_gpio_request_one(&pdev->dev, template->slow,
	gpio_get_value(template->slow) ?
	GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW,
	template->name);
	if (ret) {
	dev_err(&pdev->dev, "%s: failed to setup slow GPIO\n",
	template->name);
	return ret;
	}

	rwlock_init(&led_dat->rw_lock);

	led_dat->cdev.name = template->name;
	led_dat->cdev.default_trigger = template->default_trigger;
	led_dat->cdev.blink_set = NULL;
	led_dat->cdev.brightness_set = ns2_led_set;
	led_dat->cdev.flags \|= LED_CORE_SUSPENDRESUME;
	led_dat->cdev.groups = ns2_led_groups;
	led_dat->cmd = template->cmd;
	led_dat->slow = template->slow;

	ret = ns2_led_get_mode(led_dat, &mode);
	if (ret < 0)
	return ret;

	/* Set LED initial state. */
	led_dat->sata = (mode == NS_V2_LED_SATA) ? 1 : 0;
	led_dat->cdev.brightness =
	(mode == NS_V2_LED_OFF) ? LED_OFF : LED_FULL;

	ret = led_classdev_register(&pdev->dev, &led_dat->cdev);
	if (ret < 0)
	return ret;

	return 0;
	}

	static void delete_ns2_led(struct ns2_led_data *led_dat)
	{
	led_classdev_unregister(&led_dat->cdev);
	}

	#ifdef CONFIG_OF_GPIO
	/*
	* Translate OpenFirmware node properties into platform_data.
	*/
	static int
	ns2_leds_get_of_pdata(struct device dev, struct ns2_led_platform_data pdata)
	{
	struct device_node *np = dev->of_node;
	struct device_node *child;
	struct ns2_led *leds;
	int num_leds = 0;
	int i = 0;

	num_leds = of_get_child_count(np);
	if (!num_leds)
	return -ENODEV;

	leds = devm_kzalloc(dev, num_leds * sizeof(struct ns2_led),
	GFP_KERNEL);
	if (!leds)
	return -ENOMEM;

	for_each_child_of_node(np, child) {
	const char *string;
	int ret;

	ret = of_get_named_gpio(child, "cmd-gpio", 0);
	if (ret < 0)
	return ret;
	leds[i].cmd = ret;
	ret = of_get_named_gpio(child, "slow-gpio", 0);
	if (ret < 0)
	return ret;
	leds[i].slow = ret;
	ret = of_property_read_string(child, "label", &string);
	leds[i].name = (ret == 0) ? string : child->name;
	ret = of_property_read_string(child, "linux,default-trigger",
	&string);
	if (ret == 0)
	leds[i].default_trigger = string;

	i++;
	}

	pdata->leds = leds;
	pdata->num_leds = num_leds;

	return 0;
	}

	static const struct of_device_id of_ns2_leds_match[] = {
	{ .compatible = "lacie,ns2-leds", },
	{},
	};
	#endif /* CONFIG_OF_GPIO */

	struct ns2_led_priv {
	int num_leds;
	struct ns2_led_data leds_data[];
	};

	static inline int sizeof_ns2_led_priv(int num_leds)
	{
	return sizeof(struct ns2_led_priv) +
	(sizeof(struct ns2_led_data) * num_leds);
	}

	static int ns2_led_probe(struct platform_device *pdev)
	{
	struct ns2_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
	struct ns2_led_priv *priv;
	int i;
	int ret;

	#ifdef CONFIG_OF_GPIO
	if (!pdata) {
	pdata = devm_kzalloc(&pdev->dev,
	sizeof(struct ns2_led_platform_data),
	GFP_KERNEL);
	if (!pdata)
	return -ENOMEM;

	ret = ns2_leds_get_of_pdata(&pdev->dev, pdata);
	if (ret)
	return ret;
	}
	#else
	if (!pdata)
	return -EINVAL;
	#endif /* CONFIG_OF_GPIO */

	priv = devm_kzalloc(&pdev->dev,
	sizeof_ns2_led_priv(pdata->num_leds), GFP_KERNEL);
	if (!priv)
	return -ENOMEM;
	priv->num_leds = pdata->num_leds;

	for (i = 0; i < priv->num_leds; i++) {
	ret = create_ns2_led(pdev, &priv->leds_data[i],
	&pdata->leds[i]);
	if (ret < 0) {
	for (i = i - 1; i >= 0; i--)
	delete_ns2_led(&priv->leds_data[i]);
	return ret;
	}
	}

	platform_set_drvdata(pdev, priv);

	return 0;
	}

	static int ns2_led_remove(struct platform_device *pdev)
	{
	int i;
	struct ns2_led_priv *priv;

	priv = platform_get_drvdata(pdev);

	for (i = 0; i < priv->num_leds; i++)
	delete_ns2_led(&priv->leds_data[i]);

	return 0;
	}

	static struct platform_driver ns2_led_driver = {
	.probe = ns2_led_probe,
	.remove = ns2_led_remove,
	.driver = {
	.name = "leds-ns2",
	.of_match_table = of_match_ptr(of_ns2_leds_match),
	},
	};

	module_platform_driver(ns2_led_driver);

	MODULE_AUTHOR("Simon Guinot <sguinot@lacie.com>");
	MODULE_DESCRIPTION("Network Space v2 LED driver");
	MODULE_LICENSE("GPL");
	MODULE_ALIAS("platform:leds-ns2");