[net-next-2.6.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 = gpio_request(alarm->gpio, "GPIO fan alarm");
	if (err)
		return err;

	err = gpio_direction_input(alarm->gpio);
	if (err)
		goto err_free_gpio;

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

	/*
	 * 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);
	set_irq_type(alarm_irq, IRQ_TYPE_EDGE_BOTH);
	err = request_irq(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);
err_free_gpio:
	gpio_free(alarm->gpio);

	return err;
}

static void fan_alarm_free(struct gpio_fan_data *fan_data)
{
	struct platform_device *pdev = fan_data->pdev;
	int alarm_irq = gpio_to_irq(fan_data->alarm->gpio);

	if (alarm_irq >= 0)
		free_irq(alarm_irq, fan_data);
	device_remove_file(&pdev->dev, &dev_attr_fan1_alarm);
	gpio_free(fan_data->alarm->gpio);
}

/*
 * 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 (strict_strtoul(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 (strict_strtoul(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 (strict_strtoul(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 = gpio_request(ctrl[i], "GPIO fan control");
		if (err)
			goto err_free_gpio;

		err = gpio_direction_output(ctrl[i], gpio_get_value(ctrl[i]));
		if (err) {
			gpio_free(ctrl[i]);
			goto err_free_gpio;
		}
	}

	err = sysfs_create_group(&pdev->dev.kobj, &gpio_fan_ctrl_group);
	if (err)
		goto err_free_gpio;

	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) {
		err = -ENODEV;
		goto err_free_gpio;
	}

	return 0;

err_free_gpio:
	for (i = i - 1; i >= 0; i--)
		gpio_free(ctrl[i]);

	return err;
}

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

	sysfs_remove_group(&pdev->dev.kobj, &gpio_fan_ctrl_group);
	for (i = 0; i < fan_data->num_ctrl; i++)
		gpio_free(fan_data->ctrl[i]);
}

/*
 * 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 = kzalloc(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)
			goto err_free_data;
	}

	/* 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);
err_free_data:
	platform_set_drvdata(pdev, NULL);
	kfree(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);
	kfree(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",
	},
};

static int __init gpio_fan_init(void)
{
	return platform_driver_register(&gpio_fan_driver);
}

static void __exit gpio_fan_exit(void)
{
	platform_driver_unregister(&gpio_fan_driver);
}

module_init(gpio_fan_init);
module_exit(gpio_fan_exit);

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
98	err = gpio_request(alarm->gpio, "GPIO fan alarm");
99	if (err)
100	return err;
101
102	err = gpio_direction_input(alarm->gpio);
103	if (err)
104	goto err_free_gpio;
105
106	err = device_create_file(&pdev->dev, &dev_attr_fan1_alarm);
107	if (err)
108	goto err_free_gpio;
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);
119	set_irq_type(alarm_irq, IRQ_TYPE_EDGE_BOTH);
120	err = request_irq(alarm_irq, fan_alarm_irq_handler, IRQF_SHARED,
121	"GPIO fan alarm", fan_data);
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);
129	err_free_gpio:
130	gpio_free(alarm->gpio);
131
132	return err;
133	}
134
135	static void fan_alarm_free(struct gpio_fan_data *fan_data)
136	{
137	struct platform_device *pdev = fan_data->pdev;
138	int alarm_irq = gpio_to_irq(fan_data->alarm->gpio);
139
140	if (alarm_irq >= 0)
141	free_irq(alarm_irq, fan_data);
142	device_remove_file(&pdev->dev, &dev_attr_fan1_alarm);
143	gpio_free(fan_data->alarm->gpio);
144	}
145
146	/*
147	* Control GPIOs.
148	*/
149
150	/* Must be called with fan_data->lock held, except during initialization. */
151	static void __set_fan_ctrl(struct gpio_fan_data *fan_data, int ctrl_val)
152	{
153	int i;
154
155	for (i = 0; i < fan_data->num_ctrl; i++)
156	gpio_set_value(fan_data->ctrl[i], (ctrl_val >> i) & 1);
157	}
158
159	static int __get_fan_ctrl(struct gpio_fan_data *fan_data)
160	{
161	int i;
162	int ctrl_val = 0;
163
164	for (i = 0; i < fan_data->num_ctrl; i++) {
165	int value;
166
167	value = gpio_get_value(fan_data->ctrl[i]);
168	ctrl_val \|= (value << i);
169	}
170	return ctrl_val;
171	}
172
173	/* Must be called with fan_data->lock held, except during initialization. */
174	static void set_fan_speed(struct gpio_fan_data *fan_data, int speed_index)
175	{
176	if (fan_data->speed_index == speed_index)
177	return;
178
179	__set_fan_ctrl(fan_data, fan_data->speed[speed_index].ctrl_val);
180	fan_data->speed_index = speed_index;
181	}
182
183	static int get_fan_speed_index(struct gpio_fan_data *fan_data)
184	{
185	int ctrl_val = __get_fan_ctrl(fan_data);
186	int i;
187
188	for (i = 0; i < fan_data->num_speed; i++)
189	if (fan_data->speed[i].ctrl_val == ctrl_val)
190	return i;
191
192	dev_warn(&fan_data->pdev->dev,
193	"missing speed array entry for GPIO value 0x%x\n", ctrl_val);
194
195	return -EINVAL;
196	}
197
198	static int rpm_to_speed_index(struct gpio_fan_data *fan_data, int rpm)
199	{
200	struct gpio_fan_speed *speed = fan_data->speed;
201	int i;
202
203	for (i = 0; i < fan_data->num_speed; i++)
204	if (speed[i].rpm >= rpm)
205	return i;
206
207	return fan_data->num_speed - 1;
208	}
209
210	static ssize_t show_pwm(struct device *dev,
211	struct device_attribute attr, char buf)
212	{
213	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
214	u8 pwm = fan_data->speed_index * 255 / (fan_data->num_speed - 1);
215
216	return sprintf(buf, "%d\n", pwm);
217	}
218
219	static ssize_t set_pwm(struct device dev, struct device_attribute attr,
220	const char *buf, size_t count)
221	{
222	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
223	unsigned long pwm;
224	int speed_index;
225	int ret = count;
226
227	if (strict_strtoul(buf, 10, &pwm) \|\| pwm > 255)
228	return -EINVAL;
229
230	mutex_lock(&fan_data->lock);
231
232	if (!fan_data->pwm_enable) {
233	ret = -EPERM;
234	goto exit_unlock;
235	}
236
237	speed_index = DIV_ROUND_UP(pwm * (fan_data->num_speed - 1), 255);
238	set_fan_speed(fan_data, speed_index);
239
240	exit_unlock:
241	mutex_unlock(&fan_data->lock);
242
243	return ret;
244	}
245
246	static ssize_t show_pwm_enable(struct device *dev,
247	struct device_attribute attr, char buf)
248	{
249	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
250
251	return sprintf(buf, "%d\n", fan_data->pwm_enable);
252	}
253
254	static ssize_t set_pwm_enable(struct device dev, struct device_attribute attr,
255	const char *buf, size_t count)
256	{
257	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
258	unsigned long val;
259
260	if (strict_strtoul(buf, 10, &val) \|\| val > 1)
261	return -EINVAL;
262
263	if (fan_data->pwm_enable == val)
264	return count;
265
266	mutex_lock(&fan_data->lock);
267
268	fan_data->pwm_enable = val;
269
270	/* Disable manual control mode: set fan at full speed. */
271	if (val == 0)
272	set_fan_speed(fan_data, fan_data->num_speed - 1);
273
274	mutex_unlock(&fan_data->lock);
275
276	return count;
277	}
278
279	static ssize_t show_pwm_mode(struct device *dev,
280	struct device_attribute attr, char buf)
281	{
282	return sprintf(buf, "0\n");
283	}
284
285	static ssize_t show_rpm_min(struct device *dev,
286	struct device_attribute attr, char buf)
287	{
288	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
289
290	return sprintf(buf, "%d\n", fan_data->speed[0].rpm);
291	}
292
293	static ssize_t show_rpm_max(struct device *dev,
294	struct device_attribute attr, char buf)
295	{
296	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
297
298	return sprintf(buf, "%d\n",
299	fan_data->speed[fan_data->num_speed - 1].rpm);
300	}
301
302	static ssize_t show_rpm(struct device *dev,
303	struct device_attribute attr, char buf)
304	{
305	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
306
307	return sprintf(buf, "%d\n", fan_data->speed[fan_data->speed_index].rpm);
308	}
309
310	static ssize_t set_rpm(struct device dev, struct device_attribute attr,
311	const char *buf, size_t count)
312	{
313	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
314	unsigned long rpm;
315	int ret = count;
316
317	if (strict_strtoul(buf, 10, &rpm))
318	return -EINVAL;
319
320	mutex_lock(&fan_data->lock);
321
322	if (!fan_data->pwm_enable) {
323	ret = -EPERM;
324	goto exit_unlock;
325	}
326
327	set_fan_speed(fan_data, rpm_to_speed_index(fan_data, rpm));
328
329	exit_unlock:
330	mutex_unlock(&fan_data->lock);
331
332	return ret;
333	}
334
335	static DEVICE_ATTR(pwm1, S_IRUGO \| S_IWUSR, show_pwm, set_pwm);
336	static DEVICE_ATTR(pwm1_enable, S_IRUGO \| S_IWUSR,
337	show_pwm_enable, set_pwm_enable);
338	static DEVICE_ATTR(pwm1_mode, S_IRUGO, show_pwm_mode, NULL);
339	static DEVICE_ATTR(fan1_min, S_IRUGO, show_rpm_min, NULL);
340	static DEVICE_ATTR(fan1_max, S_IRUGO, show_rpm_max, NULL);
341	static DEVICE_ATTR(fan1_input, S_IRUGO, show_rpm, NULL);
342	static DEVICE_ATTR(fan1_target, S_IRUGO \| S_IWUSR, show_rpm, set_rpm);
343
344	static struct attribute *gpio_fan_ctrl_attributes[] = {
345	&dev_attr_pwm1.attr,
346	&dev_attr_pwm1_enable.attr,
347	&dev_attr_pwm1_mode.attr,
348	&dev_attr_fan1_input.attr,
349	&dev_attr_fan1_target.attr,
350	&dev_attr_fan1_min.attr,
351	&dev_attr_fan1_max.attr,
352	NULL
353	};
354
355	static const struct attribute_group gpio_fan_ctrl_group = {
356	.attrs = gpio_fan_ctrl_attributes,
357	};
358
359	static int fan_ctrl_init(struct gpio_fan_data *fan_data,
360	struct gpio_fan_platform_data *pdata)
361	{
362	struct platform_device *pdev = fan_data->pdev;
363	int num_ctrl = pdata->num_ctrl;
364	unsigned *ctrl = pdata->ctrl;
365	int i, err;
366
367	for (i = 0; i < num_ctrl; i++) {
368	err = gpio_request(ctrl[i], "GPIO fan control");
369	if (err)
370	goto err_free_gpio;
371
372	err = gpio_direction_output(ctrl[i], gpio_get_value(ctrl[i]));
373	if (err) {
374	gpio_free(ctrl[i]);
375	goto err_free_gpio;
376	}
377	}
378
379	err = sysfs_create_group(&pdev->dev.kobj, &gpio_fan_ctrl_group);
380	if (err)
381	goto err_free_gpio;
382
383	fan_data->num_ctrl = num_ctrl;
384	fan_data->ctrl = ctrl;
385	fan_data->num_speed = pdata->num_speed;
386	fan_data->speed = pdata->speed;
387	fan_data->pwm_enable = true; /* Enable manual fan speed control. */
388	fan_data->speed_index = get_fan_speed_index(fan_data);
389	if (fan_data->speed_index < 0) {
390	err = -ENODEV;
391	goto err_free_gpio;
392	}
393
394	return 0;
395
396	err_free_gpio:
397	for (i = i - 1; i >= 0; i--)
398	gpio_free(ctrl[i]);
399
400	return err;
401	}
402
403	static void fan_ctrl_free(struct gpio_fan_data *fan_data)
404	{
405	struct platform_device *pdev = fan_data->pdev;
406	int i;
407
408	sysfs_remove_group(&pdev->dev.kobj, &gpio_fan_ctrl_group);
409	for (i = 0; i < fan_data->num_ctrl; i++)
410	gpio_free(fan_data->ctrl[i]);
411	}
412
413	/*
414	* Platform driver.
415	*/
416
417	static ssize_t show_name(struct device *dev,
418	struct device_attribute attr, char buf)
419	{
420	return sprintf(buf, "gpio-fan\n");
421	}
422
423	static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
424
425	static int __devinit gpio_fan_probe(struct platform_device *pdev)
426	{
427	int err;
428	struct gpio_fan_data *fan_data;
429	struct gpio_fan_platform_data *pdata = pdev->dev.platform_data;
430
431	if (!pdata)
432	return -EINVAL;
433
434	fan_data = kzalloc(sizeof(struct gpio_fan_data), GFP_KERNEL);
435	if (!fan_data)
436	return -ENOMEM;
437
438	fan_data->pdev = pdev;
439	platform_set_drvdata(pdev, fan_data);
440	mutex_init(&fan_data->lock);
441
442	/* Configure alarm GPIO if available. */
443	if (pdata->alarm) {
444	err = fan_alarm_init(fan_data, pdata->alarm);
445	if (err)
446	goto err_free_data;
447	}
448
449	/* Configure control GPIOs if available. */
450	if (pdata->ctrl && pdata->num_ctrl > 0) {
451	if (!pdata->speed \|\| pdata->num_speed <= 1) {
452	err = -EINVAL;
453	goto err_free_alarm;
454	}
455	err = fan_ctrl_init(fan_data, pdata);
456	if (err)
457	goto err_free_alarm;
458	}
459
460	err = device_create_file(&pdev->dev, &dev_attr_name);
461	if (err)
462	goto err_free_ctrl;
463
464	/* Make this driver part of hwmon class. */
465	fan_data->hwmon_dev = hwmon_device_register(&pdev->dev);
466	if (IS_ERR(fan_data->hwmon_dev)) {
467	err = PTR_ERR(fan_data->hwmon_dev);
468	goto err_remove_name;
469	}
470
471	dev_info(&pdev->dev, "GPIO fan initialized\n");
472
473	return 0;
474
475	err_remove_name:
476	device_remove_file(&pdev->dev, &dev_attr_name);
477	err_free_ctrl:
478	if (fan_data->ctrl)
479	fan_ctrl_free(fan_data);
480	err_free_alarm:
481	if (fan_data->alarm)
482	fan_alarm_free(fan_data);
483	err_free_data:
484	platform_set_drvdata(pdev, NULL);
485	kfree(fan_data);
486
487	return err;
488	}
489
490	static int __devexit gpio_fan_remove(struct platform_device *pdev)
491	{
492	struct gpio_fan_data *fan_data = platform_get_drvdata(pdev);
493
494	hwmon_device_unregister(fan_data->hwmon_dev);
495	device_remove_file(&pdev->dev, &dev_attr_name);
496	if (fan_data->alarm)
497	fan_alarm_free(fan_data);
498	if (fan_data->ctrl)
499	fan_ctrl_free(fan_data);
500	kfree(fan_data);
501
502	return 0;
503	}
504
505	#ifdef CONFIG_PM
506	static int gpio_fan_suspend(struct platform_device *pdev, pm_message_t state)
507	{
508	struct gpio_fan_data *fan_data = platform_get_drvdata(pdev);
509
510	if (fan_data->ctrl) {
511	fan_data->resume_speed = fan_data->speed_index;
512	set_fan_speed(fan_data, 0);
513	}
514
515	return 0;
516	}
517
518	static int gpio_fan_resume(struct platform_device *pdev)
519	{
520	struct gpio_fan_data *fan_data = platform_get_drvdata(pdev);
521
522	if (fan_data->ctrl)
523	set_fan_speed(fan_data, fan_data->resume_speed);
524
525	return 0;
526	}
527	#else
528	#define gpio_fan_suspend NULL
529	#define gpio_fan_resume NULL
530	#endif
531
532	static struct platform_driver gpio_fan_driver = {
533	.probe = gpio_fan_probe,
534	.remove = __devexit_p(gpio_fan_remove),
535	.suspend = gpio_fan_suspend,
536	.resume = gpio_fan_resume,
537	.driver = {
538	.name = "gpio-fan",
539	},
540	};
541
542	static int __init gpio_fan_init(void)
543	{
544	return platform_driver_register(&gpio_fan_driver);
545	}
546
547	static void __exit gpio_fan_exit(void)
548	{
549	platform_driver_unregister(&gpio_fan_driver);
550	}
551
552	module_init(gpio_fan_init);
553	module_exit(gpio_fan_exit);
554
555	MODULE_AUTHOR("Simon Guinot <sguinot@lacie.com>");
556	MODULE_DESCRIPTION("GPIO FAN driver");
557	MODULE_LICENSE("GPL");
558	MODULE_ALIAS("platform:gpio-fan");