[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.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_cansleep(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;

	/*
	 * 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);
	return err;
}

/*
 * 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_cansleep(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_cansleep(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 -ENODEV;
}

static int rpm_to_speed_index(struct gpio_fan_data *fan_data, unsigned long 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 umode_t gpio_fan_is_visible(struct kobject *kobj,
				   struct attribute *attr, int index)
{
	struct device *dev = container_of(kobj, struct device, kobj);
	struct gpio_fan_data *data = dev_get_drvdata(dev);

	if (index == 0 && !data->alarm)
		return 0;
	if (index > 0 && !data->ctrl)
		return 0;

	return attr->mode;
}

static struct attribute *gpio_fan_attributes[] = {
	&dev_attr_fan1_alarm.attr,		/* 0 */
	&dev_attr_pwm1.attr,			/* 1 */
	&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_group = {
	.attrs = gpio_fan_attributes,
	.is_visible = gpio_fan_is_visible,
};

static const struct attribute_group *gpio_fan_groups[] = {
	&gpio_fan_group,
	NULL
};

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_cansleep(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 fan_data->speed_index;

	return 0;
}

#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 <= 0) {
		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") > 0) {
		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 const 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 = dev_get_platdata(&pdev->dev);

#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)
			return -EINVAL;
		err = fan_ctrl_init(fan_data, pdata);
		if (err)
			return err;
	}

	/* Make this driver part of hwmon class. */
	fan_data->hwmon_dev =
		devm_hwmon_device_register_with_groups(&pdev->dev,
						       "gpio_fan", fan_data,
						       gpio_fan_groups);
	if (IS_ERR(fan_data->hwmon_dev))
		return PTR_ERR(fan_data->hwmon_dev);

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

	return 0;
}

static void gpio_fan_shutdown(struct platform_device *pdev)
{
	struct gpio_fan_data *fan_data = dev_get_drvdata(&pdev->dev);

	if (fan_data->ctrl)
		set_fan_speed(fan_data, 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,
	.shutdown	= gpio_fan_shutdown,
	.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>
c50588ab	34	#include <linux/of.h>
55fb8b06 JL	35	#include <linux/of_platform.h>
55fb8b06 JL	36	#include <linux/of_gpio.h>
d6fe1360 SG	37
	38	struct gpio_fan_data {
	39	struct platform_device *pdev;
	40	struct device *hwmon_dev;
	41	struct mutex lock; /* lock GPIOs operations. */
	42	int num_ctrl;
	43	unsigned *ctrl;
	44	int num_speed;
	45	struct gpio_fan_speed *speed;
	46	int speed_index;
6d20a6c0	47	#ifdef CONFIG_PM_SLEEP
d6fe1360 SG	48	int resume_speed;
	49	#endif
	50	bool pwm_enable;
	51	struct gpio_fan_alarm *alarm;
	52	struct work_struct alarm_work;
	53	};
	54
	55	/*
	56	* Alarm GPIO.
	57	*/
	58
	59	static void fan_alarm_notify(struct work_struct *ws)
	60	{
	61	struct gpio_fan_data *fan_data =
	62	container_of(ws, struct gpio_fan_data, alarm_work);
	63
	64	sysfs_notify(&fan_data->pdev->dev.kobj, NULL, "fan1_alarm");
	65	kobject_uevent(&fan_data->pdev->dev.kobj, KOBJ_CHANGE);
	66	}
	67
	68	static irqreturn_t fan_alarm_irq_handler(int irq, void *dev_id)
	69	{
	70	struct gpio_fan_data *fan_data = dev_id;
	71
	72	schedule_work(&fan_data->alarm_work);
	73
	74	return IRQ_NONE;
	75	}
	76
	77	static ssize_t show_fan_alarm(struct device *dev,
	78	struct device_attribute attr, char buf)
	79	{
	80	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	81	struct gpio_fan_alarm *alarm = fan_data->alarm;
52a95c11	82	int value = gpio_get_value_cansleep(alarm->gpio);
d6fe1360 SG	83
	84	if (alarm->active_low)
	85	value = !value;
	86
	87	return sprintf(buf, "%d\n", value);
	88	}
	89
	90	static DEVICE_ATTR(fan1_alarm, S_IRUGO, show_fan_alarm, NULL);
	91
	92	static int fan_alarm_init(struct gpio_fan_data *fan_data,
	93	struct gpio_fan_alarm *alarm)
	94	{
	95	int err;
	96	int alarm_irq;
	97	struct platform_device *pdev = fan_data->pdev;
	98
	99	fan_data->alarm = alarm;
	100
d00985f3	101	err = devm_gpio_request(&pdev->dev, alarm->gpio, "GPIO fan alarm");
d6fe1360 SG	102	if (err)
	103	return err;
	104
	105	err = gpio_direction_input(alarm->gpio);
	106	if (err)
d00985f3	107	return err;
d6fe1360	108
d6fe1360 SG	109	/*
	110	* If the alarm GPIO don't support interrupts, just leave
	111	* without initializing the fail notification support.
	112	*/
	113	alarm_irq = gpio_to_irq(alarm->gpio);
	114	if (alarm_irq < 0)
	115	return 0;
	116
	117	INIT_WORK(&fan_data->alarm_work, fan_alarm_notify);
dced35ae	118	irq_set_irq_type(alarm_irq, IRQ_TYPE_EDGE_BOTH);
d00985f3 GR	119	err = devm_request_irq(&pdev->dev, alarm_irq, fan_alarm_irq_handler,
d00985f3 GR	120	IRQF_SHARED, "GPIO fan alarm", fan_data);
d6fe1360 SG	121	return err;
	122	}
	123
d6fe1360 SG	124	/*
	125	* Control GPIOs.
	126	*/
	127
	128	/* Must be called with fan_data->lock held, except during initialization. */
	129	static void __set_fan_ctrl(struct gpio_fan_data *fan_data, int ctrl_val)
	130	{
	131	int i;
	132
	133	for (i = 0; i < fan_data->num_ctrl; i++)
52a95c11	134	gpio_set_value_cansleep(fan_data->ctrl[i], (ctrl_val >> i) & 1);
d6fe1360 SG	135	}
	136
	137	static int __get_fan_ctrl(struct gpio_fan_data *fan_data)
	138	{
	139	int i;
	140	int ctrl_val = 0;
	141
	142	for (i = 0; i < fan_data->num_ctrl; i++) {
	143	int value;
	144
52a95c11	145	value = gpio_get_value_cansleep(fan_data->ctrl[i]);
d6fe1360 SG	146	ctrl_val \|= (value << i);
	147	}
	148	return ctrl_val;
	149	}
	150
	151	/* Must be called with fan_data->lock held, except during initialization. */
	152	static void set_fan_speed(struct gpio_fan_data *fan_data, int speed_index)
	153	{
	154	if (fan_data->speed_index == speed_index)
	155	return;
	156
	157	__set_fan_ctrl(fan_data, fan_data->speed[speed_index].ctrl_val);
	158	fan_data->speed_index = speed_index;
	159	}
	160
	161	static int get_fan_speed_index(struct gpio_fan_data *fan_data)
	162	{
	163	int ctrl_val = __get_fan_ctrl(fan_data);
	164	int i;
	165
	166	for (i = 0; i < fan_data->num_speed; i++)
	167	if (fan_data->speed[i].ctrl_val == ctrl_val)
	168	return i;
	169
	170	dev_warn(&fan_data->pdev->dev,
	171	"missing speed array entry for GPIO value 0x%x\n", ctrl_val);
	172
c52ae3d2	173	return -ENODEV;
d6fe1360 SG	174	}
d6fe1360 SG	175
2565fb05	176	static int rpm_to_speed_index(struct gpio_fan_data *fan_data, unsigned long rpm)
d6fe1360 SG	177	{
	178	struct gpio_fan_speed *speed = fan_data->speed;
	179	int i;
	180
	181	for (i = 0; i < fan_data->num_speed; i++)
	182	if (speed[i].rpm >= rpm)
	183	return i;
	184
	185	return fan_data->num_speed - 1;
	186	}
	187
	188	static ssize_t show_pwm(struct device *dev,
	189	struct device_attribute attr, char buf)
	190	{
	191	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	192	u8 pwm = fan_data->speed_index * 255 / (fan_data->num_speed - 1);
	193
	194	return sprintf(buf, "%d\n", pwm);
	195	}
	196
	197	static ssize_t set_pwm(struct device dev, struct device_attribute attr,
	198	const char *buf, size_t count)
	199	{
	200	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	201	unsigned long pwm;
	202	int speed_index;
	203	int ret = count;
	204
179c4fdb	205	if (kstrtoul(buf, 10, &pwm) \|\| pwm > 255)
d6fe1360 SG	206	return -EINVAL;
	207
	208	mutex_lock(&fan_data->lock);
	209
	210	if (!fan_data->pwm_enable) {
	211	ret = -EPERM;
	212	goto exit_unlock;
	213	}
	214
	215	speed_index = DIV_ROUND_UP(pwm * (fan_data->num_speed - 1), 255);
	216	set_fan_speed(fan_data, speed_index);
	217
	218	exit_unlock:
	219	mutex_unlock(&fan_data->lock);
	220
	221	return ret;
	222	}
	223
	224	static ssize_t show_pwm_enable(struct device *dev,
	225	struct device_attribute attr, char buf)
	226	{
	227	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	228
	229	return sprintf(buf, "%d\n", fan_data->pwm_enable);
	230	}
	231
	232	static ssize_t set_pwm_enable(struct device dev, struct device_attribute attr,
	233	const char *buf, size_t count)
	234	{
	235	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	236	unsigned long val;
	237
179c4fdb	238	if (kstrtoul(buf, 10, &val) \|\| val > 1)
d6fe1360 SG	239	return -EINVAL;
	240
	241	if (fan_data->pwm_enable == val)
	242	return count;
	243
	244	mutex_lock(&fan_data->lock);
	245
	246	fan_data->pwm_enable = val;
	247
	248	/* Disable manual control mode: set fan at full speed. */
	249	if (val == 0)
	250	set_fan_speed(fan_data, fan_data->num_speed - 1);
	251
	252	mutex_unlock(&fan_data->lock);
	253
	254	return count;
	255	}
	256
	257	static ssize_t show_pwm_mode(struct device *dev,
	258	struct device_attribute attr, char buf)
	259	{
	260	return sprintf(buf, "0\n");
	261	}
	262
	263	static ssize_t show_rpm_min(struct device *dev,
	264	struct device_attribute attr, char buf)
	265	{
	266	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	267
	268	return sprintf(buf, "%d\n", fan_data->speed[0].rpm);
	269	}
	270
	271	static ssize_t show_rpm_max(struct device *dev,
	272	struct device_attribute attr, char buf)
	273	{
	274	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	275
	276	return sprintf(buf, "%d\n",
	277	fan_data->speed[fan_data->num_speed - 1].rpm);
	278	}
	279
	280	static ssize_t show_rpm(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[fan_data->speed_index].rpm);
	286	}
	287
	288	static ssize_t set_rpm(struct device dev, struct device_attribute attr,
	289	const char *buf, size_t count)
	290	{
	291	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	292	unsigned long rpm;
	293	int ret = count;
	294
179c4fdb	295	if (kstrtoul(buf, 10, &rpm))
d6fe1360 SG	296	return -EINVAL;
	297
	298	mutex_lock(&fan_data->lock);
	299
	300	if (!fan_data->pwm_enable) {
	301	ret = -EPERM;
	302	goto exit_unlock;
	303	}
	304
	305	set_fan_speed(fan_data, rpm_to_speed_index(fan_data, rpm));
	306
	307	exit_unlock:
	308	mutex_unlock(&fan_data->lock);
	309
	310	return ret;
	311	}
	312
	313	static DEVICE_ATTR(pwm1, S_IRUGO \| S_IWUSR, show_pwm, set_pwm);
	314	static DEVICE_ATTR(pwm1_enable, S_IRUGO \| S_IWUSR,
	315	show_pwm_enable, set_pwm_enable);
	316	static DEVICE_ATTR(pwm1_mode, S_IRUGO, show_pwm_mode, NULL);
	317	static DEVICE_ATTR(fan1_min, S_IRUGO, show_rpm_min, NULL);
	318	static DEVICE_ATTR(fan1_max, S_IRUGO, show_rpm_max, NULL);
	319	static DEVICE_ATTR(fan1_input, S_IRUGO, show_rpm, NULL);
	320	static DEVICE_ATTR(fan1_target, S_IRUGO \| S_IWUSR, show_rpm, set_rpm);
	321
c81cc5a4 GR	322	static umode_t gpio_fan_is_visible(struct kobject *kobj,
	323	struct attribute *attr, int index)
	324	{
	325	struct device *dev = container_of(kobj, struct device, kobj);
	326	struct gpio_fan_data *data = dev_get_drvdata(dev);
	327
7258a125	328	if (index == 0 && !data->alarm)
c81cc5a4	329	return 0;
7258a125	330	if (index > 0 && !data->ctrl)
c81cc5a4 GR	331	return 0;
	332
	333	return attr->mode;
	334	}
	335
	336	static struct attribute *gpio_fan_attributes[] = {
7258a125 GR	337	&dev_attr_fan1_alarm.attr, /* 0 */
7258a125 GR	338	&dev_attr_pwm1.attr, /* 1 */
d6fe1360 SG	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
c81cc5a4 GR	348	static const struct attribute_group gpio_fan_group = {
	349	.attrs = gpio_fan_attributes,
	350	.is_visible = gpio_fan_is_visible,
d6fe1360 SG	351	};
d6fe1360 SG	352
7258a125 GR	353	static const struct attribute_group *gpio_fan_groups[] = {
	354	&gpio_fan_group,
	355	NULL
	356	};
	357
d6fe1360 SG	358	static int fan_ctrl_init(struct gpio_fan_data *fan_data,
	359	struct gpio_fan_platform_data *pdata)
	360	{
	361	struct platform_device *pdev = fan_data->pdev;
	362	int num_ctrl = pdata->num_ctrl;
	363	unsigned *ctrl = pdata->ctrl;
	364	int i, err;
	365
	366	for (i = 0; i < num_ctrl; i++) {
d00985f3 GR	367	err = devm_gpio_request(&pdev->dev, ctrl[i],
d00985f3 GR	368	"GPIO fan control");
d6fe1360	369	if (err)
d00985f3	370	return err;
d6fe1360	371
52a95c11 NM	372	err = gpio_direction_output(ctrl[i],
52a95c11 NM	373	gpio_get_value_cansleep(ctrl[i]));
d00985f3 GR	374	if (err)
d00985f3 GR	375	return err;
d6fe1360 SG	376	}
d6fe1360 SG	377
d6fe1360 SG	378	fan_data->num_ctrl = num_ctrl;
	379	fan_data->ctrl = ctrl;
	380	fan_data->num_speed = pdata->num_speed;
	381	fan_data->speed = pdata->speed;
	382	fan_data->pwm_enable = true; /* Enable manual fan speed control. */
	383	fan_data->speed_index = get_fan_speed_index(fan_data);
d00985f3	384	if (fan_data->speed_index < 0)
c52ae3d2	385	return fan_data->speed_index;
d6fe1360	386
c81cc5a4	387	return 0;
d6fe1360 SG	388	}
d6fe1360 SG	389
55fb8b06 JL	390	#ifdef CONFIG_OF_GPIO
	391	/*
	392	* Translate OpenFirmware node properties into platform_data
	393	*/
	394	static int gpio_fan_get_of_pdata(struct device *dev,
	395	struct gpio_fan_platform_data *pdata)
	396	{
	397	struct device_node *node;
	398	struct gpio_fan_speed *speed;
	399	unsigned *ctrl;
	400	unsigned i;
	401	u32 u;
	402	struct property *prop;
	403	const __be32 *p;
	404
	405	node = dev->of_node;
	406
	407	/* Fill GPIO pin array */
	408	pdata->num_ctrl = of_gpio_count(node);
e80beb27	409	if (pdata->num_ctrl <= 0) {
55fb8b06 JL	410	dev_err(dev, "gpios DT property empty / missing");
	411	return -ENODEV;
	412	}
	413	ctrl = devm_kzalloc(dev, pdata->num_ctrl * sizeof(unsigned),
	414	GFP_KERNEL);
	415	if (!ctrl)
	416	return -ENOMEM;
	417	for (i = 0; i < pdata->num_ctrl; i++) {
	418	int val;
	419
	420	val = of_get_gpio(node, i);
	421	if (val < 0)
	422	return val;
	423	ctrl[i] = val;
	424	}
	425	pdata->ctrl = ctrl;
	426
	427	/* Get number of RPM/ctrl_val pairs in speed map */
	428	prop = of_find_property(node, "gpio-fan,speed-map", &i);
	429	if (!prop) {
	430	dev_err(dev, "gpio-fan,speed-map DT property missing");
	431	return -ENODEV;
	432	}
	433	i = i / sizeof(u32);
	434	if (i == 0 \|\| i & 1) {
	435	dev_err(dev, "gpio-fan,speed-map contains zero/odd number of entries");
	436	return -ENODEV;
	437	}
	438	pdata->num_speed = i / 2;
	439
	440	/*
	441	* Populate speed map
	442	* Speed map is in the form <RPM ctrl_val RPM ctrl_val ...>
	443	* this needs splitting into pairs to create gpio_fan_speed structs
	444	*/
	445	speed = devm_kzalloc(dev,
	446	pdata->num_speed * sizeof(struct gpio_fan_speed),
	447	GFP_KERNEL);
	448	if (!speed)
	449	return -ENOMEM;
	450	p = NULL;
	451	for (i = 0; i < pdata->num_speed; i++) {
	452	p = of_prop_next_u32(prop, p, &u);
	453	if (!p)
	454	return -ENODEV;
	455	speed[i].rpm = u;
	456	p = of_prop_next_u32(prop, p, &u);
	457	if (!p)
	458	return -ENODEV;
	459	speed[i].ctrl_val = u;
	460	}
	461	pdata->speed = speed;
	462
	463	/* Alarm GPIO if one exists */
e80beb27	464	if (of_gpio_named_count(node, "alarm-gpios") > 0) {
55fb8b06 JL	465	struct gpio_fan_alarm *alarm;
	466	int val;
	467	enum of_gpio_flags flags;
	468
	469	alarm = devm_kzalloc(dev, sizeof(struct gpio_fan_alarm),
	470	GFP_KERNEL);
	471	if (!alarm)
	472	return -ENOMEM;
	473
	474	val = of_get_named_gpio_flags(node, "alarm-gpios", 0, &flags);
	475	if (val < 0)
	476	return val;
	477	alarm->gpio = val;
	478	alarm->active_low = flags & OF_GPIO_ACTIVE_LOW;
	479
	480	pdata->alarm = alarm;
	481	}
	482
	483	return 0;
	484	}
	485
6de709c5	486	static const struct of_device_id of_gpio_fan_match[] = {
55fb8b06 JL	487	{ .compatible = "gpio-fan", },
	488	{},
	489	};
	490	#endif /* CONFIG_OF_GPIO */
	491
6c931ae1	492	static int gpio_fan_probe(struct platform_device *pdev)
d6fe1360 SG	493	{
	494	int err;
	495	struct gpio_fan_data *fan_data;
a8b3a3a5	496	struct gpio_fan_platform_data *pdata = dev_get_platdata(&pdev->dev);
d6fe1360	497
55fb8b06 JL	498	#ifdef CONFIG_OF_GPIO
	499	if (!pdata) {
	500	pdata = devm_kzalloc(&pdev->dev,
	501	sizeof(struct gpio_fan_platform_data),
	502	GFP_KERNEL);
	503	if (!pdata)
	504	return -ENOMEM;
	505
	506	err = gpio_fan_get_of_pdata(&pdev->dev, pdata);
	507	if (err)
	508	return err;
	509	}
	510	#else /* CONFIG_OF_GPIO */
d6fe1360 SG	511	if (!pdata)
d6fe1360 SG	512	return -EINVAL;
55fb8b06	513	#endif /* CONFIG_OF_GPIO */
d6fe1360	514
d00985f3 GR	515	fan_data = devm_kzalloc(&pdev->dev, sizeof(struct gpio_fan_data),
d00985f3 GR	516	GFP_KERNEL);
d6fe1360 SG	517	if (!fan_data)
	518	return -ENOMEM;
	519
	520	fan_data->pdev = pdev;
	521	platform_set_drvdata(pdev, fan_data);
	522	mutex_init(&fan_data->lock);
	523
	524	/* Configure alarm GPIO if available. */
	525	if (pdata->alarm) {
	526	err = fan_alarm_init(fan_data, pdata->alarm);
	527	if (err)
d00985f3	528	return err;
d6fe1360 SG	529	}
	530
	531	/* Configure control GPIOs if available. */
	532	if (pdata->ctrl && pdata->num_ctrl > 0) {
c81cc5a4 GR	533	if (!pdata->speed \|\| pdata->num_speed <= 1)
c81cc5a4 GR	534	return -EINVAL;
d6fe1360 SG	535	err = fan_ctrl_init(fan_data, pdata);
d6fe1360 SG	536	if (err)
c81cc5a4	537	return err;
d6fe1360 SG	538	}
d6fe1360 SG	539
d6fe1360	540	/* Make this driver part of hwmon class. */
49153b09 AL	541	fan_data->hwmon_dev =
	542	devm_hwmon_device_register_with_groups(&pdev->dev,
	543	"gpio_fan", fan_data,
	544	gpio_fan_groups);
7258a125 GR	545	if (IS_ERR(fan_data->hwmon_dev))
7258a125 GR	546	return PTR_ERR(fan_data->hwmon_dev);
d6fe1360 SG	547
	548	dev_info(&pdev->dev, "GPIO fan initialized\n");
	549
	550	return 0;
d6fe1360 SG	551	}
d6fe1360 SG	552
b95579cd NM	553	static void gpio_fan_shutdown(struct platform_device *pdev)
	554	{
	555	struct gpio_fan_data *fan_data = dev_get_drvdata(&pdev->dev);
	556
	557	if (fan_data->ctrl)
	558	set_fan_speed(fan_data, 0);
	559	}
	560
6d20a6c0 RW	561	#ifdef CONFIG_PM_SLEEP
6d20a6c0 RW	562	static int gpio_fan_suspend(struct device *dev)
d6fe1360	563	{
6d20a6c0	564	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
d6fe1360 SG	565
	566	if (fan_data->ctrl) {
	567	fan_data->resume_speed = fan_data->speed_index;
	568	set_fan_speed(fan_data, 0);
	569	}
	570
	571	return 0;
	572	}
	573
6d20a6c0	574	static int gpio_fan_resume(struct device *dev)
d6fe1360	575	{
6d20a6c0	576	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
d6fe1360 SG	577
	578	if (fan_data->ctrl)
	579	set_fan_speed(fan_data, fan_data->resume_speed);
	580
	581	return 0;
	582	}
6d20a6c0 RW	583
6d20a6c0 RW	584	static SIMPLE_DEV_PM_OPS(gpio_fan_pm, gpio_fan_suspend, gpio_fan_resume);
24f9c539	585	#define GPIO_FAN_PM (&gpio_fan_pm)
d6fe1360	586	#else
6d20a6c0	587	#define GPIO_FAN_PM NULL
d6fe1360 SG	588	#endif
	589
	590	static struct platform_driver gpio_fan_driver = {
	591	.probe = gpio_fan_probe,
b95579cd	592	.shutdown = gpio_fan_shutdown,
d6fe1360 SG	593	.driver = {
d6fe1360 SG	594	.name = "gpio-fan",
6d20a6c0	595	.pm = GPIO_FAN_PM,
eaa7cc60	596	#ifdef CONFIG_OF_GPIO
55fb8b06	597	.of_match_table = of_match_ptr(of_gpio_fan_match),
eaa7cc60	598	#endif
d6fe1360 SG	599	},
	600	};
	601
25a236a5	602	module_platform_driver(gpio_fan_driver);
d6fe1360 SG	603
	604	MODULE_AUTHOR("Simon Guinot <sguinot@lacie.com>");
	605	MODULE_DESCRIPTION("GPIO FAN driver");
	606	MODULE_LICENSE("GPL");
	607	MODULE_ALIAS("platform:gpio-fan");