[deliverable/linux.git] / drivers / hwmon / gpio-fan.c

/*
 * gpio-fan.c - Hwmon driver for fans connected to GPIO lines.
 *
 * Copyright (C) 2010 LaCie
 *
 * Author: Simon Guinot <sguinot@lacie.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/slab.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/platform_device.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/hwmon.h>
#include <linux/gpio.h>
#include <linux/gpio-fan.h>
#include <linux/of_platform.h>
#include <linux/of_gpio.h>

struct gpio_fan_data {
	struct platform_device	*pdev;
	struct device		*hwmon_dev;
	struct mutex		lock; /* lock GPIOs operations. */
	int			num_ctrl;
	unsigned		*ctrl;
	int			num_speed;
	struct gpio_fan_speed	*speed;
	int			speed_index;
#ifdef CONFIG_PM_SLEEP
	int			resume_speed;
#endif
	bool			pwm_enable;
	struct gpio_fan_alarm	*alarm;
	struct work_struct	alarm_work;
};

/*
 * Alarm GPIO.
 */

static void fan_alarm_notify(struct work_struct *ws)
{
	struct gpio_fan_data *fan_data =
		container_of(ws, struct gpio_fan_data, alarm_work);

	sysfs_notify(&fan_data->pdev->dev.kobj, NULL, "fan1_alarm");
	kobject_uevent(&fan_data->pdev->dev.kobj, KOBJ_CHANGE);
}

static irqreturn_t fan_alarm_irq_handler(int irq, void *dev_id)
{
	struct gpio_fan_data *fan_data = dev_id;

	schedule_work(&fan_data->alarm_work);

	return IRQ_NONE;
}

static ssize_t show_fan_alarm(struct device *dev,
			      struct device_attribute *attr, char *buf)
{
	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	struct gpio_fan_alarm *alarm = fan_data->alarm;
	int value = gpio_get_value(alarm->gpio);

	if (alarm->active_low)
		value = !value;

	return sprintf(buf, "%d\n", value);
}

static DEVICE_ATTR(fan1_alarm, S_IRUGO, show_fan_alarm, NULL);

static int fan_alarm_init(struct gpio_fan_data *fan_data,
			  struct gpio_fan_alarm *alarm)
{
	int err;
	int alarm_irq;
	struct platform_device *pdev = fan_data->pdev;

	fan_data->alarm = alarm;

	err = devm_gpio_request(&pdev->dev, alarm->gpio, "GPIO fan alarm");
	if (err)
		return err;

	err = gpio_direction_input(alarm->gpio);
	if (err)
		return err;

	err = device_create_file(&pdev->dev, &dev_attr_fan1_alarm);
	if (err)
		return err;

	/*
	 * If the alarm GPIO don't support interrupts, just leave
	 * without initializing the fail notification support.
	 */
	alarm_irq = gpio_to_irq(alarm->gpio);
	if (alarm_irq < 0)
		return 0;

	INIT_WORK(&fan_data->alarm_work, fan_alarm_notify);
	irq_set_irq_type(alarm_irq, IRQ_TYPE_EDGE_BOTH);
	err = devm_request_irq(&pdev->dev, alarm_irq, fan_alarm_irq_handler,
			       IRQF_SHARED, "GPIO fan alarm", fan_data);
	if (err)
		goto err_free_sysfs;

	return 0;

err_free_sysfs:
	device_remove_file(&pdev->dev, &dev_attr_fan1_alarm);
	return err;
}

static void fan_alarm_free(struct gpio_fan_data *fan_data)
{
	struct platform_device *pdev = fan_data->pdev;

	device_remove_file(&pdev->dev, &dev_attr_fan1_alarm);
}

/*
 * Control GPIOs.
 */

/* Must be called with fan_data->lock held, except during initialization. */
static void __set_fan_ctrl(struct gpio_fan_data *fan_data, int ctrl_val)
{
	int i;

	for (i = 0; i < fan_data->num_ctrl; i++)
		gpio_set_value(fan_data->ctrl[i], (ctrl_val >> i) & 1);
}

static int __get_fan_ctrl(struct gpio_fan_data *fan_data)
{
	int i;
	int ctrl_val = 0;

	for (i = 0; i < fan_data->num_ctrl; i++) {
		int value;

		value = gpio_get_value(fan_data->ctrl[i]);
		ctrl_val |= (value << i);
	}
	return ctrl_val;
}

/* Must be called with fan_data->lock held, except during initialization. */
static void set_fan_speed(struct gpio_fan_data *fan_data, int speed_index)
{
	if (fan_data->speed_index == speed_index)
		return;

	__set_fan_ctrl(fan_data, fan_data->speed[speed_index].ctrl_val);
	fan_data->speed_index = speed_index;
}

static int get_fan_speed_index(struct gpio_fan_data *fan_data)
{
	int ctrl_val = __get_fan_ctrl(fan_data);
	int i;

	for (i = 0; i < fan_data->num_speed; i++)
		if (fan_data->speed[i].ctrl_val == ctrl_val)
			return i;

	dev_warn(&fan_data->pdev->dev,
		 "missing speed array entry for GPIO value 0x%x\n", ctrl_val);

	return -EINVAL;
}

static int rpm_to_speed_index(struct gpio_fan_data *fan_data, int rpm)
{
	struct gpio_fan_speed *speed = fan_data->speed;
	int i;

	for (i = 0; i < fan_data->num_speed; i++)
		if (speed[i].rpm >= rpm)
			return i;

	return fan_data->num_speed - 1;
}

static ssize_t show_pwm(struct device *dev,
			struct device_attribute *attr, char *buf)
{
	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	u8 pwm = fan_data->speed_index * 255 / (fan_data->num_speed - 1);

	return sprintf(buf, "%d\n", pwm);
}

static ssize_t set_pwm(struct device *dev, struct device_attribute *attr,
		       const char *buf, size_t count)
{
	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	unsigned long pwm;
	int speed_index;
	int ret = count;

	if (kstrtoul(buf, 10, &pwm) || pwm > 255)
		return -EINVAL;

	mutex_lock(&fan_data->lock);

	if (!fan_data->pwm_enable) {
		ret = -EPERM;
		goto exit_unlock;
	}

	speed_index = DIV_ROUND_UP(pwm * (fan_data->num_speed - 1), 255);
	set_fan_speed(fan_data, speed_index);

exit_unlock:
	mutex_unlock(&fan_data->lock);

	return ret;
}

static ssize_t show_pwm_enable(struct device *dev,
			       struct device_attribute *attr, char *buf)
{
	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);

	return sprintf(buf, "%d\n", fan_data->pwm_enable);
}

static ssize_t set_pwm_enable(struct device *dev, struct device_attribute *attr,
			      const char *buf, size_t count)
{
	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	unsigned long val;

	if (kstrtoul(buf, 10, &val) || val > 1)
		return -EINVAL;

	if (fan_data->pwm_enable == val)
		return count;

	mutex_lock(&fan_data->lock);

	fan_data->pwm_enable = val;

	/* Disable manual control mode: set fan at full speed. */
	if (val == 0)
		set_fan_speed(fan_data, fan_data->num_speed - 1);

	mutex_unlock(&fan_data->lock);

	return count;
}

static ssize_t show_pwm_mode(struct device *dev,
			     struct device_attribute *attr, char *buf)
{
	return sprintf(buf, "0\n");
}

static ssize_t show_rpm_min(struct device *dev,
			    struct device_attribute *attr, char *buf)
{
	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);

	return sprintf(buf, "%d\n", fan_data->speed[0].rpm);
}

static ssize_t show_rpm_max(struct device *dev,
			    struct device_attribute *attr, char *buf)
{
	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);

	return sprintf(buf, "%d\n",
		       fan_data->speed[fan_data->num_speed - 1].rpm);
}

static ssize_t show_rpm(struct device *dev,
			struct device_attribute *attr, char *buf)
{
	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);

	return sprintf(buf, "%d\n", fan_data->speed[fan_data->speed_index].rpm);
}

static ssize_t set_rpm(struct device *dev, struct device_attribute *attr,
		       const char *buf, size_t count)
{
	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	unsigned long rpm;
	int ret = count;

	if (kstrtoul(buf, 10, &rpm))
		return -EINVAL;

	mutex_lock(&fan_data->lock);

	if (!fan_data->pwm_enable) {
		ret = -EPERM;
		goto exit_unlock;
	}

	set_fan_speed(fan_data, rpm_to_speed_index(fan_data, rpm));

exit_unlock:
	mutex_unlock(&fan_data->lock);

	return ret;
}

static DEVICE_ATTR(pwm1, S_IRUGO | S_IWUSR, show_pwm, set_pwm);
static DEVICE_ATTR(pwm1_enable, S_IRUGO | S_IWUSR,
		   show_pwm_enable, set_pwm_enable);
static DEVICE_ATTR(pwm1_mode, S_IRUGO, show_pwm_mode, NULL);
static DEVICE_ATTR(fan1_min, S_IRUGO, show_rpm_min, NULL);
static DEVICE_ATTR(fan1_max, S_IRUGO, show_rpm_max, NULL);
static DEVICE_ATTR(fan1_input, S_IRUGO, show_rpm, NULL);
static DEVICE_ATTR(fan1_target, S_IRUGO | S_IWUSR, show_rpm, set_rpm);

static struct attribute *gpio_fan_ctrl_attributes[] = {
	&dev_attr_pwm1.attr,
	&dev_attr_pwm1_enable.attr,
	&dev_attr_pwm1_mode.attr,
	&dev_attr_fan1_input.attr,
	&dev_attr_fan1_target.attr,
	&dev_attr_fan1_min.attr,
	&dev_attr_fan1_max.attr,
	NULL
};

static const struct attribute_group gpio_fan_ctrl_group = {
	.attrs = gpio_fan_ctrl_attributes,
};

static int fan_ctrl_init(struct gpio_fan_data *fan_data,
			 struct gpio_fan_platform_data *pdata)
{
	struct platform_device *pdev = fan_data->pdev;
	int num_ctrl = pdata->num_ctrl;
	unsigned *ctrl = pdata->ctrl;
	int i, err;

	for (i = 0; i < num_ctrl; i++) {
		err = devm_gpio_request(&pdev->dev, ctrl[i],
					"GPIO fan control");
		if (err)
			return err;

		err = gpio_direction_output(ctrl[i], gpio_get_value(ctrl[i]));
		if (err)
			return err;
	}

	fan_data->num_ctrl = num_ctrl;
	fan_data->ctrl = ctrl;
	fan_data->num_speed = pdata->num_speed;
	fan_data->speed = pdata->speed;
	fan_data->pwm_enable = true; /* Enable manual fan speed control. */
	fan_data->speed_index = get_fan_speed_index(fan_data);
	if (fan_data->speed_index < 0)
		return -ENODEV;

	err = sysfs_create_group(&pdev->dev.kobj, &gpio_fan_ctrl_group);
	return err;
}

static void fan_ctrl_free(struct gpio_fan_data *fan_data)
{
	struct platform_device *pdev = fan_data->pdev;

	sysfs_remove_group(&pdev->dev.kobj, &gpio_fan_ctrl_group);
}

/*
 * Platform driver.
 */

static ssize_t show_name(struct device *dev,
			 struct device_attribute *attr, char *buf)
{
	return sprintf(buf, "gpio-fan\n");
}

static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);


#ifdef CONFIG_OF_GPIO
/*
 * Translate OpenFirmware node properties into platform_data
 */
static int gpio_fan_get_of_pdata(struct device *dev,
			    struct gpio_fan_platform_data *pdata)
{
	struct device_node *node;
	struct gpio_fan_speed *speed;
	unsigned *ctrl;
	unsigned i;
	u32 u;
	struct property *prop;
	const __be32 *p;

	node = dev->of_node;

	/* Fill GPIO pin array */
	pdata->num_ctrl = of_gpio_count(node);
	if (!pdata->num_ctrl) {
		dev_err(dev, "gpios DT property empty / missing");
		return -ENODEV;
	}
	ctrl = devm_kzalloc(dev, pdata->num_ctrl * sizeof(unsigned),
				GFP_KERNEL);
	if (!ctrl)
		return -ENOMEM;
	for (i = 0; i < pdata->num_ctrl; i++) {
		int val;

		val = of_get_gpio(node, i);
		if (val < 0)
			return val;
		ctrl[i] = val;
	}
	pdata->ctrl = ctrl;

	/* Get number of RPM/ctrl_val pairs in speed map */
	prop = of_find_property(node, "gpio-fan,speed-map", &i);
	if (!prop) {
		dev_err(dev, "gpio-fan,speed-map DT property missing");
		return -ENODEV;
	}
	i = i / sizeof(u32);
	if (i == 0 || i & 1) {
		dev_err(dev, "gpio-fan,speed-map contains zero/odd number of entries");
		return -ENODEV;
	}
	pdata->num_speed = i / 2;

	/*
	 * Populate speed map
	 * Speed map is in the form <RPM ctrl_val RPM ctrl_val ...>
	 * this needs splitting into pairs to create gpio_fan_speed structs
	 */
	speed = devm_kzalloc(dev,
			pdata->num_speed * sizeof(struct gpio_fan_speed),
			GFP_KERNEL);
	if (!speed)
		return -ENOMEM;
	p = NULL;
	for (i = 0; i < pdata->num_speed; i++) {
		p = of_prop_next_u32(prop, p, &u);
		if (!p)
			return -ENODEV;
		speed[i].rpm = u;
		p = of_prop_next_u32(prop, p, &u);
		if (!p)
			return -ENODEV;
		speed[i].ctrl_val = u;
	}
	pdata->speed = speed;

	/* Alarm GPIO if one exists */
	if (of_gpio_named_count(node, "alarm-gpios")) {
		struct gpio_fan_alarm *alarm;
		int val;
		enum of_gpio_flags flags;

		alarm = devm_kzalloc(dev, sizeof(struct gpio_fan_alarm),
					GFP_KERNEL);
		if (!alarm)
			return -ENOMEM;

		val = of_get_named_gpio_flags(node, "alarm-gpios", 0, &flags);
		if (val < 0)
			return val;
		alarm->gpio = val;
		alarm->active_low = flags & OF_GPIO_ACTIVE_LOW;

		pdata->alarm = alarm;
	}

	return 0;
}

static struct of_device_id of_gpio_fan_match[] = {
	{ .compatible = "gpio-fan", },
	{},
};
#endif /* CONFIG_OF_GPIO */

static int gpio_fan_probe(struct platform_device *pdev)
{
	int err;
	struct gpio_fan_data *fan_data;
	struct gpio_fan_platform_data *pdata = pdev->dev.platform_data;

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

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

	fan_data = devm_kzalloc(&pdev->dev, sizeof(struct gpio_fan_data),
				GFP_KERNEL);
	if (!fan_data)
		return -ENOMEM;

	fan_data->pdev = pdev;
	platform_set_drvdata(pdev, fan_data);
	mutex_init(&fan_data->lock);

	/* Configure alarm GPIO if available. */
	if (pdata->alarm) {
		err = fan_alarm_init(fan_data, pdata->alarm);
		if (err)
			return err;
	}

	/* Configure control GPIOs if available. */
	if (pdata->ctrl && pdata->num_ctrl > 0) {
		if (!pdata->speed || pdata->num_speed <= 1) {
			err = -EINVAL;
			goto err_free_alarm;
		}
		err = fan_ctrl_init(fan_data, pdata);
		if (err)
			goto err_free_alarm;
	}

	err = device_create_file(&pdev->dev, &dev_attr_name);
	if (err)
		goto err_free_ctrl;

	/* Make this driver part of hwmon class. */
	fan_data->hwmon_dev = hwmon_device_register(&pdev->dev);
	if (IS_ERR(fan_data->hwmon_dev)) {
		err = PTR_ERR(fan_data->hwmon_dev);
		goto err_remove_name;
	}

	dev_info(&pdev->dev, "GPIO fan initialized\n");

	return 0;

err_remove_name:
	device_remove_file(&pdev->dev, &dev_attr_name);
err_free_ctrl:
	if (fan_data->ctrl)
		fan_ctrl_free(fan_data);
err_free_alarm:
	if (fan_data->alarm)
		fan_alarm_free(fan_data);
	return err;
}

static int gpio_fan_remove(struct platform_device *pdev)
{
	struct gpio_fan_data *fan_data = platform_get_drvdata(pdev);

	hwmon_device_unregister(fan_data->hwmon_dev);
	device_remove_file(&pdev->dev, &dev_attr_name);
	if (fan_data->alarm)
		fan_alarm_free(fan_data);
	if (fan_data->ctrl)
		fan_ctrl_free(fan_data);

	return 0;
}

#ifdef CONFIG_PM_SLEEP
static int gpio_fan_suspend(struct device *dev)
{
	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);

	if (fan_data->ctrl) {
		fan_data->resume_speed = fan_data->speed_index;
		set_fan_speed(fan_data, 0);
	}

	return 0;
}

static int gpio_fan_resume(struct device *dev)
{
	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);

	if (fan_data->ctrl)
		set_fan_speed(fan_data, fan_data->resume_speed);

	return 0;
}

static SIMPLE_DEV_PM_OPS(gpio_fan_pm, gpio_fan_suspend, gpio_fan_resume);
#define GPIO_FAN_PM	&gpio_fan_pm
#else
#define GPIO_FAN_PM	NULL
#endif

static struct platform_driver gpio_fan_driver = {
	.probe		= gpio_fan_probe,
	.remove		= gpio_fan_remove,
	.driver	= {
		.name	= "gpio-fan",
		.pm	= GPIO_FAN_PM,
#ifdef CONFIG_OF_GPIO
		.of_match_table = of_match_ptr(of_gpio_fan_match),
#endif
	},
};

module_platform_driver(gpio_fan_driver);

MODULE_AUTHOR("Simon Guinot <sguinot@lacie.com>");
MODULE_DESCRIPTION("GPIO FAN driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:gpio-fan");
Commit	Line	Data
d6fe1360 SG	1	/*
	2	* gpio-fan.c - Hwmon driver for fans connected to GPIO lines.
	3	*
	4	* Copyright (C) 2010 LaCie
	5	*
	6	* Author: Simon Guinot <sguinot@lacie.com>
	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License as published by
	10	* the Free Software Foundation; either version 2 of the License, or
	11	* (at your option) any later version.
	12	*
	13	* This program is distributed in the hope that it will be useful,
	14	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	16	* GNU General Public License for more details.
	17	*
	18	* You should have received a copy of the GNU General Public License
	19	* along with this program; if not, write to the Free Software
	20	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	21	*/
	22
	23	#include <linux/module.h>
	24	#include <linux/init.h>
	25	#include <linux/slab.h>
	26	#include <linux/interrupt.h>
	27	#include <linux/irq.h>
	28	#include <linux/platform_device.h>
	29	#include <linux/err.h>
	30	#include <linux/mutex.h>
	31	#include <linux/hwmon.h>
	32	#include <linux/gpio.h>
	33	#include <linux/gpio-fan.h>
55fb8b06 JL	34	#include <linux/of_platform.h>
55fb8b06 JL	35	#include <linux/of_gpio.h>
d6fe1360 SG	36
	37	struct gpio_fan_data {
	38	struct platform_device *pdev;
	39	struct device *hwmon_dev;
	40	struct mutex lock; /* lock GPIOs operations. */
	41	int num_ctrl;
	42	unsigned *ctrl;
	43	int num_speed;
	44	struct gpio_fan_speed *speed;
	45	int speed_index;
6d20a6c0	46	#ifdef CONFIG_PM_SLEEP
d6fe1360 SG	47	int resume_speed;
	48	#endif
	49	bool pwm_enable;
	50	struct gpio_fan_alarm *alarm;
	51	struct work_struct alarm_work;
	52	};
	53
	54	/*
	55	* Alarm GPIO.
	56	*/
	57
	58	static void fan_alarm_notify(struct work_struct *ws)
	59	{
	60	struct gpio_fan_data *fan_data =
	61	container_of(ws, struct gpio_fan_data, alarm_work);
	62
	63	sysfs_notify(&fan_data->pdev->dev.kobj, NULL, "fan1_alarm");
	64	kobject_uevent(&fan_data->pdev->dev.kobj, KOBJ_CHANGE);
	65	}
	66
	67	static irqreturn_t fan_alarm_irq_handler(int irq, void *dev_id)
	68	{
	69	struct gpio_fan_data *fan_data = dev_id;
	70
	71	schedule_work(&fan_data->alarm_work);
	72
	73	return IRQ_NONE;
	74	}
	75
	76	static ssize_t show_fan_alarm(struct device *dev,
	77	struct device_attribute attr, char buf)
	78	{
	79	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	80	struct gpio_fan_alarm *alarm = fan_data->alarm;
	81	int value = gpio_get_value(alarm->gpio);
	82
	83	if (alarm->active_low)
	84	value = !value;
	85
	86	return sprintf(buf, "%d\n", value);
	87	}
	88
	89	static DEVICE_ATTR(fan1_alarm, S_IRUGO, show_fan_alarm, NULL);
	90
	91	static int fan_alarm_init(struct gpio_fan_data *fan_data,
	92	struct gpio_fan_alarm *alarm)
	93	{
	94	int err;
	95	int alarm_irq;
	96	struct platform_device *pdev = fan_data->pdev;
	97
	98	fan_data->alarm = alarm;
	99
d00985f3	100	err = devm_gpio_request(&pdev->dev, alarm->gpio, "GPIO fan alarm");
d6fe1360 SG	101	if (err)
	102	return err;
	103
	104	err = gpio_direction_input(alarm->gpio);
	105	if (err)
d00985f3	106	return err;
d6fe1360 SG	107
	108	err = device_create_file(&pdev->dev, &dev_attr_fan1_alarm);
	109	if (err)
d00985f3	110	return err;
d6fe1360 SG	111
	112	/*
	113	* If the alarm GPIO don't support interrupts, just leave
	114	* without initializing the fail notification support.
	115	*/
	116	alarm_irq = gpio_to_irq(alarm->gpio);
	117	if (alarm_irq < 0)
	118	return 0;
	119
	120	INIT_WORK(&fan_data->alarm_work, fan_alarm_notify);
dced35ae	121	irq_set_irq_type(alarm_irq, IRQ_TYPE_EDGE_BOTH);
d00985f3 GR	122	err = devm_request_irq(&pdev->dev, alarm_irq, fan_alarm_irq_handler,
d00985f3 GR	123	IRQF_SHARED, "GPIO fan alarm", fan_data);
d6fe1360 SG	124	if (err)
	125	goto err_free_sysfs;
	126
	127	return 0;
	128
	129	err_free_sysfs:
	130	device_remove_file(&pdev->dev, &dev_attr_fan1_alarm);
d6fe1360 SG	131	return err;
	132	}
	133
	134	static void fan_alarm_free(struct gpio_fan_data *fan_data)
	135	{
	136	struct platform_device *pdev = fan_data->pdev;
d6fe1360	137
d6fe1360	138	device_remove_file(&pdev->dev, &dev_attr_fan1_alarm);
d6fe1360 SG	139	}
	140
	141	/*
	142	* Control GPIOs.
	143	*/
	144
	145	/* Must be called with fan_data->lock held, except during initialization. */
	146	static void __set_fan_ctrl(struct gpio_fan_data *fan_data, int ctrl_val)
	147	{
	148	int i;
	149
	150	for (i = 0; i < fan_data->num_ctrl; i++)
	151	gpio_set_value(fan_data->ctrl[i], (ctrl_val >> i) & 1);
	152	}
	153
	154	static int __get_fan_ctrl(struct gpio_fan_data *fan_data)
	155	{
	156	int i;
	157	int ctrl_val = 0;
	158
	159	for (i = 0; i < fan_data->num_ctrl; i++) {
	160	int value;
	161
	162	value = gpio_get_value(fan_data->ctrl[i]);
	163	ctrl_val \|= (value << i);
	164	}
	165	return ctrl_val;
	166	}
	167
	168	/* Must be called with fan_data->lock held, except during initialization. */
	169	static void set_fan_speed(struct gpio_fan_data *fan_data, int speed_index)
	170	{
	171	if (fan_data->speed_index == speed_index)
	172	return;
	173
	174	__set_fan_ctrl(fan_data, fan_data->speed[speed_index].ctrl_val);
	175	fan_data->speed_index = speed_index;
	176	}
	177
	178	static int get_fan_speed_index(struct gpio_fan_data *fan_data)
	179	{
	180	int ctrl_val = __get_fan_ctrl(fan_data);
	181	int i;
	182
	183	for (i = 0; i < fan_data->num_speed; i++)
	184	if (fan_data->speed[i].ctrl_val == ctrl_val)
	185	return i;
	186
	187	dev_warn(&fan_data->pdev->dev,
	188	"missing speed array entry for GPIO value 0x%x\n", ctrl_val);
	189
	190	return -EINVAL;
	191	}
	192
	193	static int rpm_to_speed_index(struct gpio_fan_data *fan_data, int rpm)
	194	{
	195	struct gpio_fan_speed *speed = fan_data->speed;
	196	int i;
	197
	198	for (i = 0; i < fan_data->num_speed; i++)
	199	if (speed[i].rpm >= rpm)
	200	return i;
	201
	202	return fan_data->num_speed - 1;
203	}
204
205	static ssize_t show_pwm(struct device *dev,
206	struct device_attribute attr, char buf)
207	{
208	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
209	u8 pwm = fan_data->speed_index * 255 / (fan_data->num_speed - 1);
210
211	return sprintf(buf, "%d\n", pwm);
212	}
213
214	static ssize_t set_pwm(struct device dev, struct device_attribute attr,
215	const char *buf, size_t count)
216	{
217	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
218	unsigned long pwm;
219	int speed_index;
220	int ret = count;
221
179c4fdb	222	if (kstrtoul(buf, 10, &pwm) \|\| pwm > 255)
d6fe1360 SG	223	return -EINVAL;
	224
	225	mutex_lock(&fan_data->lock);
	226
	227	if (!fan_data->pwm_enable) {
	228	ret = -EPERM;
	229	goto exit_unlock;
	230	}
	231
	232	speed_index = DIV_ROUND_UP(pwm * (fan_data->num_speed - 1), 255);
	233	set_fan_speed(fan_data, speed_index);
	234
	235	exit_unlock:
	236	mutex_unlock(&fan_data->lock);
	237
	238	return ret;
	239	}
	240
	241	static ssize_t show_pwm_enable(struct device *dev,
	242	struct device_attribute attr, char buf)
	243	{
	244	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	245
	246	return sprintf(buf, "%d\n", fan_data->pwm_enable);
	247	}
	248
	249	static ssize_t set_pwm_enable(struct device dev, struct device_attribute attr,
	250	const char *buf, size_t count)
	251	{
	252	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	253	unsigned long val;
	254
179c4fdb	255	if (kstrtoul(buf, 10, &val) \|\| val > 1)
d6fe1360 SG	256	return -EINVAL;
	257
	258	if (fan_data->pwm_enable == val)
	259	return count;
	260
	261	mutex_lock(&fan_data->lock);
	262
	263	fan_data->pwm_enable = val;
	264
	265	/* Disable manual control mode: set fan at full speed. */
	266	if (val == 0)
	267	set_fan_speed(fan_data, fan_data->num_speed - 1);
	268
	269	mutex_unlock(&fan_data->lock);
	270
	271	return count;
	272	}
	273
	274	static ssize_t show_pwm_mode(struct device *dev,
	275	struct device_attribute attr, char buf)
	276	{
	277	return sprintf(buf, "0\n");
	278	}
	279
	280	static ssize_t show_rpm_min(struct device *dev,
	281	struct device_attribute attr, char buf)
	282	{
	283	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	284
	285	return sprintf(buf, "%d\n", fan_data->speed[0].rpm);
	286	}
	287
	288	static ssize_t show_rpm_max(struct device *dev,
	289	struct device_attribute attr, char buf)
	290	{
	291	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	292
	293	return sprintf(buf, "%d\n",
	294	fan_data->speed[fan_data->num_speed - 1].rpm);
	295	}
	296
	297	static ssize_t show_rpm(struct device *dev,
	298	struct device_attribute attr, char buf)
	299	{
	300	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	301
	302	return sprintf(buf, "%d\n", fan_data->speed[fan_data->speed_index].rpm);
	303	}
	304
	305	static ssize_t set_rpm(struct device dev, struct device_attribute attr,
	306	const char *buf, size_t count)
	307	{
	308	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	309	unsigned long rpm;
	310	int ret = count;
	311
179c4fdb	312	if (kstrtoul(buf, 10, &rpm))
d6fe1360 SG	313	return -EINVAL;
	314
	315	mutex_lock(&fan_data->lock);
	316
	317	if (!fan_data->pwm_enable) {
	318	ret = -EPERM;
	319	goto exit_unlock;
	320	}
	321
	322	set_fan_speed(fan_data, rpm_to_speed_index(fan_data, rpm));
	323
	324	exit_unlock:
	325	mutex_unlock(&fan_data->lock);
	326
	327	return ret;
	328	}
	329
	330	static DEVICE_ATTR(pwm1, S_IRUGO \| S_IWUSR, show_pwm, set_pwm);
	331	static DEVICE_ATTR(pwm1_enable, S_IRUGO \| S_IWUSR,
	332	show_pwm_enable, set_pwm_enable);
	333	static DEVICE_ATTR(pwm1_mode, S_IRUGO, show_pwm_mode, NULL);
	334	static DEVICE_ATTR(fan1_min, S_IRUGO, show_rpm_min, NULL);
	335	static DEVICE_ATTR(fan1_max, S_IRUGO, show_rpm_max, NULL);
	336	static DEVICE_ATTR(fan1_input, S_IRUGO, show_rpm, NULL);
	337	static DEVICE_ATTR(fan1_target, S_IRUGO \| S_IWUSR, show_rpm, set_rpm);
	338
	339	static struct attribute *gpio_fan_ctrl_attributes[] = {
	340	&dev_attr_pwm1.attr,
	341	&dev_attr_pwm1_enable.attr,
	342	&dev_attr_pwm1_mode.attr,
	343	&dev_attr_fan1_input.attr,
	344	&dev_attr_fan1_target.attr,
	345	&dev_attr_fan1_min.attr,
	346	&dev_attr_fan1_max.attr,
	347	NULL
	348	};
	349
	350	static const struct attribute_group gpio_fan_ctrl_group = {
	351	.attrs = gpio_fan_ctrl_attributes,
	352	};
	353
	354	static int fan_ctrl_init(struct gpio_fan_data *fan_data,
	355	struct gpio_fan_platform_data *pdata)
	356	{
	357	struct platform_device *pdev = fan_data->pdev;
	358	int num_ctrl = pdata->num_ctrl;
	359	unsigned *ctrl = pdata->ctrl;
	360	int i, err;
	361
	362	for (i = 0; i < num_ctrl; i++) {
d00985f3 GR	363	err = devm_gpio_request(&pdev->dev, ctrl[i],
d00985f3 GR	364	"GPIO fan control");
d6fe1360	365	if (err)
d00985f3	366	return err;
d6fe1360 SG	367
d6fe1360 SG	368	err = gpio_direction_output(ctrl[i], gpio_get_value(ctrl[i]));
d00985f3 GR	369	if (err)
d00985f3 GR	370	return err;
d6fe1360 SG	371	}
d6fe1360 SG	372
d6fe1360 SG	373	fan_data->num_ctrl = num_ctrl;
	374	fan_data->ctrl = ctrl;
	375	fan_data->num_speed = pdata->num_speed;
	376	fan_data->speed = pdata->speed;
	377	fan_data->pwm_enable = true; /* Enable manual fan speed control. */
	378	fan_data->speed_index = get_fan_speed_index(fan_data);
d00985f3 GR	379	if (fan_data->speed_index < 0)
d00985f3 GR	380	return -ENODEV;
d6fe1360	381
4f5b7994	382	err = sysfs_create_group(&pdev->dev.kobj, &gpio_fan_ctrl_group);
d6fe1360 SG	383	return err;
	384	}
	385
	386	static void fan_ctrl_free(struct gpio_fan_data *fan_data)
	387	{
	388	struct platform_device *pdev = fan_data->pdev;
d6fe1360 SG	389
d6fe1360 SG	390	sysfs_remove_group(&pdev->dev.kobj, &gpio_fan_ctrl_group);
d6fe1360 SG	391	}
	392
	393	/*
	394	* Platform driver.
	395	*/
	396
	397	static ssize_t show_name(struct device *dev,
	398	struct device_attribute attr, char buf)
	399	{
	400	return sprintf(buf, "gpio-fan\n");
	401	}
	402
	403	static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
	404
55fb8b06 JL	405
	406	#ifdef CONFIG_OF_GPIO
	407	/*
	408	* Translate OpenFirmware node properties into platform_data
	409	*/
	410	static int gpio_fan_get_of_pdata(struct device *dev,
	411	struct gpio_fan_platform_data *pdata)
	412	{
	413	struct device_node *node;
	414	struct gpio_fan_speed *speed;
	415	unsigned *ctrl;
	416	unsigned i;
	417	u32 u;
	418	struct property *prop;
	419	const __be32 *p;
	420
	421	node = dev->of_node;
	422
	423	/* Fill GPIO pin array */
	424	pdata->num_ctrl = of_gpio_count(node);
	425	if (!pdata->num_ctrl) {
	426	dev_err(dev, "gpios DT property empty / missing");
	427	return -ENODEV;
	428	}
	429	ctrl = devm_kzalloc(dev, pdata->num_ctrl * sizeof(unsigned),
	430	GFP_KERNEL);
	431	if (!ctrl)
	432	return -ENOMEM;
	433	for (i = 0; i < pdata->num_ctrl; i++) {
	434	int val;
	435
	436	val = of_get_gpio(node, i);
	437	if (val < 0)
	438	return val;
	439	ctrl[i] = val;
	440	}
	441	pdata->ctrl = ctrl;
	442
	443	/* Get number of RPM/ctrl_val pairs in speed map */
	444	prop = of_find_property(node, "gpio-fan,speed-map", &i);
	445	if (!prop) {
	446	dev_err(dev, "gpio-fan,speed-map DT property missing");
	447	return -ENODEV;
	448	}
	449	i = i / sizeof(u32);
	450	if (i == 0 \|\| i & 1) {
	451	dev_err(dev, "gpio-fan,speed-map contains zero/odd number of entries");
	452	return -ENODEV;
	453	}
	454	pdata->num_speed = i / 2;
	455
	456	/*
	457	* Populate speed map
	458	* Speed map is in the form <RPM ctrl_val RPM ctrl_val ...>
	459	* this needs splitting into pairs to create gpio_fan_speed structs
	460	*/
	461	speed = devm_kzalloc(dev,
	462	pdata->num_speed * sizeof(struct gpio_fan_speed),
	463	GFP_KERNEL);
	464	if (!speed)
	465	return -ENOMEM;
	466	p = NULL;
	467	for (i = 0; i < pdata->num_speed; i++) {
	468	p = of_prop_next_u32(prop, p, &u);
469	if (!p)
470	return -ENODEV;
471	speed[i].rpm = u;
472	p = of_prop_next_u32(prop, p, &u);
473	if (!p)
474	return -ENODEV;
475	speed[i].ctrl_val = u;
476	}
477	pdata->speed = speed;
478
479	/* Alarm GPIO if one exists */
480	if (of_gpio_named_count(node, "alarm-gpios")) {
481	struct gpio_fan_alarm *alarm;
482	int val;
483	enum of_gpio_flags flags;
484
485	alarm = devm_kzalloc(dev, sizeof(struct gpio_fan_alarm),
486	GFP_KERNEL);
487	if (!alarm)
488	return -ENOMEM;
489
490	val = of_get_named_gpio_flags(node, "alarm-gpios", 0, &flags);
491	if (val < 0)
492	return val;
493	alarm->gpio = val;
494	alarm->active_low = flags & OF_GPIO_ACTIVE_LOW;
495
496	pdata->alarm = alarm;
497	}
498
499	return 0;
500	}
501
a5977246	502	static struct of_device_id of_gpio_fan_match[] = {
55fb8b06 JL	503	{ .compatible = "gpio-fan", },
	504	{},
	505	};
	506	#endif /* CONFIG_OF_GPIO */
	507
6c931ae1	508	static int gpio_fan_probe(struct platform_device *pdev)
d6fe1360 SG	509	{
	510	int err;
	511	struct gpio_fan_data *fan_data;
	512	struct gpio_fan_platform_data *pdata = pdev->dev.platform_data;
	513
55fb8b06 JL	514	#ifdef CONFIG_OF_GPIO
	515	if (!pdata) {
	516	pdata = devm_kzalloc(&pdev->dev,
	517	sizeof(struct gpio_fan_platform_data),
	518	GFP_KERNEL);
	519	if (!pdata)
	520	return -ENOMEM;
	521
	522	err = gpio_fan_get_of_pdata(&pdev->dev, pdata);
	523	if (err)
	524	return err;
	525	}
	526	#else /* CONFIG_OF_GPIO */
d6fe1360 SG	527	if (!pdata)
d6fe1360 SG	528	return -EINVAL;
55fb8b06	529	#endif /* CONFIG_OF_GPIO */
d6fe1360	530
d00985f3 GR	531	fan_data = devm_kzalloc(&pdev->dev, sizeof(struct gpio_fan_data),
d00985f3 GR	532	GFP_KERNEL);
d6fe1360 SG	533	if (!fan_data)
	534	return -ENOMEM;
	535
	536	fan_data->pdev = pdev;
	537	platform_set_drvdata(pdev, fan_data);
	538	mutex_init(&fan_data->lock);
	539
	540	/* Configure alarm GPIO if available. */
	541	if (pdata->alarm) {
	542	err = fan_alarm_init(fan_data, pdata->alarm);
	543	if (err)
d00985f3	544	return err;
d6fe1360 SG	545	}
	546
	547	/* Configure control GPIOs if available. */
	548	if (pdata->ctrl && pdata->num_ctrl > 0) {
	549	if (!pdata->speed \|\| pdata->num_speed <= 1) {
	550	err = -EINVAL;
	551	goto err_free_alarm;
	552	}
	553	err = fan_ctrl_init(fan_data, pdata);
	554	if (err)
	555	goto err_free_alarm;
	556	}
	557
	558	err = device_create_file(&pdev->dev, &dev_attr_name);
	559	if (err)
	560	goto err_free_ctrl;
	561
	562	/* Make this driver part of hwmon class. */
	563	fan_data->hwmon_dev = hwmon_device_register(&pdev->dev);
	564	if (IS_ERR(fan_data->hwmon_dev)) {
	565	err = PTR_ERR(fan_data->hwmon_dev);
	566	goto err_remove_name;
	567	}
	568
	569	dev_info(&pdev->dev, "GPIO fan initialized\n");
	570
	571	return 0;
	572
	573	err_remove_name:
	574	device_remove_file(&pdev->dev, &dev_attr_name);
	575	err_free_ctrl:
	576	if (fan_data->ctrl)
	577	fan_ctrl_free(fan_data);
	578	err_free_alarm:
	579	if (fan_data->alarm)
	580	fan_alarm_free(fan_data);
d6fe1360 SG	581	return err;
	582	}
	583
281dfd0b	584	static int gpio_fan_remove(struct platform_device *pdev)
d6fe1360 SG	585	{
	586	struct gpio_fan_data *fan_data = platform_get_drvdata(pdev);
	587
	588	hwmon_device_unregister(fan_data->hwmon_dev);
	589	device_remove_file(&pdev->dev, &dev_attr_name);
	590	if (fan_data->alarm)
	591	fan_alarm_free(fan_data);
	592	if (fan_data->ctrl)
	593	fan_ctrl_free(fan_data);
d6fe1360 SG	594
	595	return 0;
	596	}
	597
6d20a6c0 RW	598	#ifdef CONFIG_PM_SLEEP
6d20a6c0 RW	599	static int gpio_fan_suspend(struct device *dev)
d6fe1360	600	{
6d20a6c0	601	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
d6fe1360 SG	602
	603	if (fan_data->ctrl) {
	604	fan_data->resume_speed = fan_data->speed_index;
	605	set_fan_speed(fan_data, 0);
	606	}
	607
	608	return 0;
	609	}
	610
6d20a6c0	611	static int gpio_fan_resume(struct device *dev)
d6fe1360	612	{
6d20a6c0	613	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
d6fe1360 SG	614
	615	if (fan_data->ctrl)
	616	set_fan_speed(fan_data, fan_data->resume_speed);
	617
	618	return 0;
	619	}
6d20a6c0 RW	620
	621	static SIMPLE_DEV_PM_OPS(gpio_fan_pm, gpio_fan_suspend, gpio_fan_resume);
	622	#define GPIO_FAN_PM &gpio_fan_pm
d6fe1360	623	#else
6d20a6c0	624	#define GPIO_FAN_PM NULL
d6fe1360 SG	625	#endif
	626
	627	static struct platform_driver gpio_fan_driver = {
	628	.probe = gpio_fan_probe,
9e5e9b7a	629	.remove = gpio_fan_remove,
d6fe1360 SG	630	.driver = {
d6fe1360 SG	631	.name = "gpio-fan",
6d20a6c0	632	.pm = GPIO_FAN_PM,
eaa7cc60	633	#ifdef CONFIG_OF_GPIO
55fb8b06	634	.of_match_table = of_match_ptr(of_gpio_fan_match),
eaa7cc60	635	#endif
d6fe1360 SG	636	},
	637	};
	638
25a236a5	639	module_platform_driver(gpio_fan_driver);
d6fe1360 SG	640
	641	MODULE_AUTHOR("Simon Guinot <sguinot@lacie.com>");
	642	MODULE_DESCRIPTION("GPIO FAN driver");
	643	MODULE_LICENSE("GPL");
	644	MODULE_ALIAS("platform:gpio-fan");