[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>

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
	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);

static int __devinit 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;

	if (!pdata)
		return -EINVAL;

	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 __devexit 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
static int gpio_fan_suspend(struct platform_device *pdev, pm_message_t state)
{
	struct gpio_fan_data *fan_data = platform_get_drvdata(pdev);

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

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

	return 0;
}
#else
#define gpio_fan_suspend NULL
#define gpio_fan_resume NULL
#endif

static struct platform_driver gpio_fan_driver = {
	.probe		= gpio_fan_probe,
	.remove		= __devexit_p(gpio_fan_remove),
	.suspend	= gpio_fan_suspend,
	.resume		= gpio_fan_resume,
	.driver	= {
		.name	= "gpio-fan",
	},
};

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>
	34
	35	struct gpio_fan_data {
	36	struct platform_device *pdev;
	37	struct device *hwmon_dev;
	38	struct mutex lock; /* lock GPIOs operations. */
	39	int num_ctrl;
	40	unsigned *ctrl;
	41	int num_speed;
	42	struct gpio_fan_speed *speed;
	43	int speed_index;
	44	#ifdef CONFIG_PM
	45	int resume_speed;
	46	#endif
	47	bool pwm_enable;
	48	struct gpio_fan_alarm *alarm;
	49	struct work_struct alarm_work;
	50	};
	51
	52	/*
	53	* Alarm GPIO.
	54	*/
	55
	56	static void fan_alarm_notify(struct work_struct *ws)
	57	{
	58	struct gpio_fan_data *fan_data =
	59	container_of(ws, struct gpio_fan_data, alarm_work);
	60
	61	sysfs_notify(&fan_data->pdev->dev.kobj, NULL, "fan1_alarm");
	62	kobject_uevent(&fan_data->pdev->dev.kobj, KOBJ_CHANGE);
	63	}
	64
65	static irqreturn_t fan_alarm_irq_handler(int irq, void *dev_id)
66	{
67	struct gpio_fan_data *fan_data = dev_id;
68
69	schedule_work(&fan_data->alarm_work);
70
71	return IRQ_NONE;
72	}
73
74	static ssize_t show_fan_alarm(struct device *dev,
75	struct device_attribute attr, char buf)
76	{
77	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
78	struct gpio_fan_alarm *alarm = fan_data->alarm;
79	int value = gpio_get_value(alarm->gpio);
80
81	if (alarm->active_low)
82	value = !value;
83
84	return sprintf(buf, "%d\n", value);
85	}
86
87	static DEVICE_ATTR(fan1_alarm, S_IRUGO, show_fan_alarm, NULL);
88
89	static int fan_alarm_init(struct gpio_fan_data *fan_data,
90	struct gpio_fan_alarm *alarm)
91	{
92	int err;
93	int alarm_irq;
94	struct platform_device *pdev = fan_data->pdev;
95
96	fan_data->alarm = alarm;
97
d00985f3	98	err = devm_gpio_request(&pdev->dev, alarm->gpio, "GPIO fan alarm");
d6fe1360 SG	99	if (err)
	100	return err;
	101
	102	err = gpio_direction_input(alarm->gpio);
	103	if (err)
d00985f3	104	return err;
d6fe1360 SG	105
	106	err = device_create_file(&pdev->dev, &dev_attr_fan1_alarm);
	107	if (err)
d00985f3	108	return err;
d6fe1360 SG	109
	110	/*
	111	* If the alarm GPIO don't support interrupts, just leave
	112	* without initializing the fail notification support.
	113	*/
	114	alarm_irq = gpio_to_irq(alarm->gpio);
	115	if (alarm_irq < 0)
	116	return 0;
	117
	118	INIT_WORK(&fan_data->alarm_work, fan_alarm_notify);
dced35ae	119	irq_set_irq_type(alarm_irq, IRQ_TYPE_EDGE_BOTH);
d00985f3 GR	120	err = devm_request_irq(&pdev->dev, alarm_irq, fan_alarm_irq_handler,
d00985f3 GR	121	IRQF_SHARED, "GPIO fan alarm", fan_data);
d6fe1360 SG	122	if (err)
	123	goto err_free_sysfs;
	124
	125	return 0;
	126
	127	err_free_sysfs:
	128	device_remove_file(&pdev->dev, &dev_attr_fan1_alarm);
d6fe1360 SG	129	return err;
	130	}
	131
	132	static void fan_alarm_free(struct gpio_fan_data *fan_data)
	133	{
	134	struct platform_device *pdev = fan_data->pdev;
d6fe1360	135
d6fe1360	136	device_remove_file(&pdev->dev, &dev_attr_fan1_alarm);
d6fe1360 SG	137	}
	138
	139	/*
	140	* Control GPIOs.
	141	*/
	142
	143	/* Must be called with fan_data->lock held, except during initialization. */
	144	static void __set_fan_ctrl(struct gpio_fan_data *fan_data, int ctrl_val)
	145	{
	146	int i;
	147
	148	for (i = 0; i < fan_data->num_ctrl; i++)
	149	gpio_set_value(fan_data->ctrl[i], (ctrl_val >> i) & 1);
	150	}
	151
	152	static int __get_fan_ctrl(struct gpio_fan_data *fan_data)
	153	{
	154	int i;
	155	int ctrl_val = 0;
	156
	157	for (i = 0; i < fan_data->num_ctrl; i++) {
	158	int value;
	159
	160	value = gpio_get_value(fan_data->ctrl[i]);
	161	ctrl_val \|= (value << i);
	162	}
	163	return ctrl_val;
	164	}
	165
	166	/* Must be called with fan_data->lock held, except during initialization. */
	167	static void set_fan_speed(struct gpio_fan_data *fan_data, int speed_index)
	168	{
	169	if (fan_data->speed_index == speed_index)
	170	return;
	171
	172	__set_fan_ctrl(fan_data, fan_data->speed[speed_index].ctrl_val);
	173	fan_data->speed_index = speed_index;
	174	}
	175
	176	static int get_fan_speed_index(struct gpio_fan_data *fan_data)
	177	{
	178	int ctrl_val = __get_fan_ctrl(fan_data);
	179	int i;
	180
	181	for (i = 0; i < fan_data->num_speed; i++)
	182	if (fan_data->speed[i].ctrl_val == ctrl_val)
	183	return i;
	184
	185	dev_warn(&fan_data->pdev->dev,
	186	"missing speed array entry for GPIO value 0x%x\n", ctrl_val);
	187
	188	return -EINVAL;
	189	}
	190
	191	static int rpm_to_speed_index(struct gpio_fan_data *fan_data, int rpm)
	192	{
	193	struct gpio_fan_speed *speed = fan_data->speed;
	194	int i;
	195
	196	for (i = 0; i < fan_data->num_speed; i++)
	197	if (speed[i].rpm >= rpm)
	198	return i;
	199
	200	return fan_data->num_speed - 1;
201	}
202
203	static ssize_t show_pwm(struct device *dev,
204	struct device_attribute attr, char buf)
205	{
206	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
207	u8 pwm = fan_data->speed_index * 255 / (fan_data->num_speed - 1);
208
209	return sprintf(buf, "%d\n", pwm);
210	}
211
212	static ssize_t set_pwm(struct device dev, struct device_attribute attr,
213	const char *buf, size_t count)
214	{
215	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
216	unsigned long pwm;
217	int speed_index;
218	int ret = count;
219
179c4fdb	220	if (kstrtoul(buf, 10, &pwm) \|\| pwm > 255)
d6fe1360 SG	221	return -EINVAL;
	222
	223	mutex_lock(&fan_data->lock);
	224
	225	if (!fan_data->pwm_enable) {
	226	ret = -EPERM;
	227	goto exit_unlock;
	228	}
	229
	230	speed_index = DIV_ROUND_UP(pwm * (fan_data->num_speed - 1), 255);
	231	set_fan_speed(fan_data, speed_index);
	232
	233	exit_unlock:
	234	mutex_unlock(&fan_data->lock);
	235
	236	return ret;
	237	}
	238
	239	static ssize_t show_pwm_enable(struct device *dev,
	240	struct device_attribute attr, char buf)
	241	{
	242	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	243
	244	return sprintf(buf, "%d\n", fan_data->pwm_enable);
	245	}
	246
	247	static ssize_t set_pwm_enable(struct device dev, struct device_attribute attr,
	248	const char *buf, size_t count)
	249	{
	250	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	251	unsigned long val;
	252
179c4fdb	253	if (kstrtoul(buf, 10, &val) \|\| val > 1)
d6fe1360 SG	254	return -EINVAL;
	255
	256	if (fan_data->pwm_enable == val)
	257	return count;
	258
	259	mutex_lock(&fan_data->lock);
	260
	261	fan_data->pwm_enable = val;
	262
	263	/* Disable manual control mode: set fan at full speed. */
	264	if (val == 0)
	265	set_fan_speed(fan_data, fan_data->num_speed - 1);
	266
	267	mutex_unlock(&fan_data->lock);
	268
	269	return count;
	270	}
	271
	272	static ssize_t show_pwm_mode(struct device *dev,
	273	struct device_attribute attr, char buf)
	274	{
	275	return sprintf(buf, "0\n");
	276	}
	277
	278	static ssize_t show_rpm_min(struct device *dev,
	279	struct device_attribute attr, char buf)
	280	{
	281	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	282
	283	return sprintf(buf, "%d\n", fan_data->speed[0].rpm);
	284	}
	285
	286	static ssize_t show_rpm_max(struct device *dev,
	287	struct device_attribute attr, char buf)
	288	{
	289	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	290
	291	return sprintf(buf, "%d\n",
	292	fan_data->speed[fan_data->num_speed - 1].rpm);
	293	}
	294
	295	static ssize_t show_rpm(struct device *dev,
	296	struct device_attribute attr, char buf)
	297	{
	298	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	299
	300	return sprintf(buf, "%d\n", fan_data->speed[fan_data->speed_index].rpm);
	301	}
	302
	303	static ssize_t set_rpm(struct device dev, struct device_attribute attr,
	304	const char *buf, size_t count)
	305	{
	306	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	307	unsigned long rpm;
	308	int ret = count;
	309
179c4fdb	310	if (kstrtoul(buf, 10, &rpm))
d6fe1360 SG	311	return -EINVAL;
	312
	313	mutex_lock(&fan_data->lock);
	314
	315	if (!fan_data->pwm_enable) {
	316	ret = -EPERM;
	317	goto exit_unlock;
	318	}
	319
	320	set_fan_speed(fan_data, rpm_to_speed_index(fan_data, rpm));
	321
	322	exit_unlock:
	323	mutex_unlock(&fan_data->lock);
	324
	325	return ret;
	326	}
	327
	328	static DEVICE_ATTR(pwm1, S_IRUGO \| S_IWUSR, show_pwm, set_pwm);
	329	static DEVICE_ATTR(pwm1_enable, S_IRUGO \| S_IWUSR,
	330	show_pwm_enable, set_pwm_enable);
	331	static DEVICE_ATTR(pwm1_mode, S_IRUGO, show_pwm_mode, NULL);
	332	static DEVICE_ATTR(fan1_min, S_IRUGO, show_rpm_min, NULL);
	333	static DEVICE_ATTR(fan1_max, S_IRUGO, show_rpm_max, NULL);
	334	static DEVICE_ATTR(fan1_input, S_IRUGO, show_rpm, NULL);
	335	static DEVICE_ATTR(fan1_target, S_IRUGO \| S_IWUSR, show_rpm, set_rpm);
	336
	337	static struct attribute *gpio_fan_ctrl_attributes[] = {
	338	&dev_attr_pwm1.attr,
	339	&dev_attr_pwm1_enable.attr,
	340	&dev_attr_pwm1_mode.attr,
	341	&dev_attr_fan1_input.attr,
	342	&dev_attr_fan1_target.attr,
	343	&dev_attr_fan1_min.attr,
	344	&dev_attr_fan1_max.attr,
	345	NULL
	346	};
	347
	348	static const struct attribute_group gpio_fan_ctrl_group = {
	349	.attrs = gpio_fan_ctrl_attributes,
	350	};
	351
	352	static int fan_ctrl_init(struct gpio_fan_data *fan_data,
	353	struct gpio_fan_platform_data *pdata)
	354	{
	355	struct platform_device *pdev = fan_data->pdev;
	356	int num_ctrl = pdata->num_ctrl;
	357	unsigned *ctrl = pdata->ctrl;
	358	int i, err;
	359
	360	for (i = 0; i < num_ctrl; i++) {
d00985f3 GR	361	err = devm_gpio_request(&pdev->dev, ctrl[i],
d00985f3 GR	362	"GPIO fan control");
d6fe1360	363	if (err)
d00985f3	364	return err;
d6fe1360 SG	365
d6fe1360 SG	366	err = gpio_direction_output(ctrl[i], gpio_get_value(ctrl[i]));
d00985f3 GR	367	if (err)
d00985f3 GR	368	return err;
d6fe1360 SG	369	}
d6fe1360 SG	370
d6fe1360 SG	371	fan_data->num_ctrl = num_ctrl;
	372	fan_data->ctrl = ctrl;
	373	fan_data->num_speed = pdata->num_speed;
	374	fan_data->speed = pdata->speed;
	375	fan_data->pwm_enable = true; /* Enable manual fan speed control. */
	376	fan_data->speed_index = get_fan_speed_index(fan_data);
d00985f3 GR	377	if (fan_data->speed_index < 0)
d00985f3 GR	378	return -ENODEV;
d6fe1360	379
4f5b7994	380	err = sysfs_create_group(&pdev->dev.kobj, &gpio_fan_ctrl_group);
d6fe1360 SG	381	return err;
	382	}
	383
	384	static void fan_ctrl_free(struct gpio_fan_data *fan_data)
	385	{
	386	struct platform_device *pdev = fan_data->pdev;
d6fe1360 SG	387
d6fe1360 SG	388	sysfs_remove_group(&pdev->dev.kobj, &gpio_fan_ctrl_group);
d6fe1360 SG	389	}
	390
	391	/*
	392	* Platform driver.
	393	*/
	394
	395	static ssize_t show_name(struct device *dev,
	396	struct device_attribute attr, char buf)
	397	{
	398	return sprintf(buf, "gpio-fan\n");
	399	}
	400
	401	static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
	402
	403	static int __devinit gpio_fan_probe(struct platform_device *pdev)
	404	{
	405	int err;
	406	struct gpio_fan_data *fan_data;
	407	struct gpio_fan_platform_data *pdata = pdev->dev.platform_data;
	408
	409	if (!pdata)
	410	return -EINVAL;
	411
d00985f3 GR	412	fan_data = devm_kzalloc(&pdev->dev, sizeof(struct gpio_fan_data),
d00985f3 GR	413	GFP_KERNEL);
d6fe1360 SG	414	if (!fan_data)
	415	return -ENOMEM;
	416
	417	fan_data->pdev = pdev;
	418	platform_set_drvdata(pdev, fan_data);
	419	mutex_init(&fan_data->lock);
	420
	421	/* Configure alarm GPIO if available. */
	422	if (pdata->alarm) {
	423	err = fan_alarm_init(fan_data, pdata->alarm);
	424	if (err)
d00985f3	425	return err;
d6fe1360 SG	426	}
	427
	428	/* Configure control GPIOs if available. */
	429	if (pdata->ctrl && pdata->num_ctrl > 0) {
	430	if (!pdata->speed \|\| pdata->num_speed <= 1) {
	431	err = -EINVAL;
	432	goto err_free_alarm;
	433	}
	434	err = fan_ctrl_init(fan_data, pdata);
	435	if (err)
	436	goto err_free_alarm;
	437	}
	438
	439	err = device_create_file(&pdev->dev, &dev_attr_name);
	440	if (err)
	441	goto err_free_ctrl;
	442
	443	/* Make this driver part of hwmon class. */
	444	fan_data->hwmon_dev = hwmon_device_register(&pdev->dev);
	445	if (IS_ERR(fan_data->hwmon_dev)) {
	446	err = PTR_ERR(fan_data->hwmon_dev);
	447	goto err_remove_name;
	448	}
	449
	450	dev_info(&pdev->dev, "GPIO fan initialized\n");
	451
	452	return 0;
	453
	454	err_remove_name:
	455	device_remove_file(&pdev->dev, &dev_attr_name);
	456	err_free_ctrl:
	457	if (fan_data->ctrl)
	458	fan_ctrl_free(fan_data);
	459	err_free_alarm:
	460	if (fan_data->alarm)
	461	fan_alarm_free(fan_data);
d6fe1360 SG	462	return err;
	463	}
	464
	465	static int __devexit gpio_fan_remove(struct platform_device *pdev)
	466	{
	467	struct gpio_fan_data *fan_data = platform_get_drvdata(pdev);
	468
	469	hwmon_device_unregister(fan_data->hwmon_dev);
	470	device_remove_file(&pdev->dev, &dev_attr_name);
	471	if (fan_data->alarm)
	472	fan_alarm_free(fan_data);
	473	if (fan_data->ctrl)
	474	fan_ctrl_free(fan_data);
d6fe1360 SG	475
	476	return 0;
	477	}
	478
	479	#ifdef CONFIG_PM
	480	static int gpio_fan_suspend(struct platform_device *pdev, pm_message_t state)
	481	{
	482	struct gpio_fan_data *fan_data = platform_get_drvdata(pdev);
	483
	484	if (fan_data->ctrl) {
	485	fan_data->resume_speed = fan_data->speed_index;
	486	set_fan_speed(fan_data, 0);
	487	}
	488
	489	return 0;
	490	}
	491
	492	static int gpio_fan_resume(struct platform_device *pdev)
	493	{
	494	struct gpio_fan_data *fan_data = platform_get_drvdata(pdev);
	495
	496	if (fan_data->ctrl)
	497	set_fan_speed(fan_data, fan_data->resume_speed);
	498
	499	return 0;
	500	}
	501	#else
	502	#define gpio_fan_suspend NULL
	503	#define gpio_fan_resume NULL
	504	#endif
	505
	506	static struct platform_driver gpio_fan_driver = {
	507	.probe = gpio_fan_probe,
	508	.remove = __devexit_p(gpio_fan_remove),
	509	.suspend = gpio_fan_suspend,
	510	.resume = gpio_fan_resume,
	511	.driver = {
	512	.name = "gpio-fan",
	513	},
	514	};
	515
25a236a5	516	module_platform_driver(gpio_fan_driver);
d6fe1360 SG	517
	518	MODULE_AUTHOR("Simon Guinot <sguinot@lacie.com>");
	519	MODULE_DESCRIPTION("GPIO FAN driver");
	520	MODULE_LICENSE("GPL");
	521	MODULE_ALIAS("platform:gpio-fan");