[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>
#include <linux/thermal.h>

struct gpio_fan_data {
	struct platform_device	*pdev;
	struct device		*hwmon_dev;
	/* Cooling device if any */
	struct thermal_cooling_device *cdev;
	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;
}

static int gpio_fan_get_max_state(struct thermal_cooling_device *cdev,
				  unsigned long *state)
{
	struct gpio_fan_data *fan_data = cdev->devdata;

	if (!fan_data)
		return -EINVAL;

	*state = fan_data->num_speed - 1;
	return 0;
}

static int gpio_fan_get_cur_state(struct thermal_cooling_device *cdev,
				  unsigned long *state)
{
	struct gpio_fan_data *fan_data = cdev->devdata;
	int r;

	if (!fan_data)
		return -EINVAL;

	r = get_fan_speed_index(fan_data);
	if (r < 0)
		return r;

	*state = r;
	return 0;
}

static int gpio_fan_set_cur_state(struct thermal_cooling_device *cdev,
				  unsigned long state)
{
	struct gpio_fan_data *fan_data = cdev->devdata;

	if (!fan_data)
		return -EINVAL;

	set_fan_speed(fan_data, state);
	return 0;
}

static const struct thermal_cooling_device_ops gpio_fan_cool_ops = {
	.get_max_state = gpio_fan_get_max_state,
	.get_cur_state = gpio_fan_get_cur_state,
	.set_cur_state = gpio_fan_set_cur_state,
};

#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;

	/* 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;
	}

	/* Fill GPIO pin array */
	pdata->num_ctrl = of_gpio_count(node);
	if (pdata->num_ctrl <= 0) {
		if (pdata->alarm)
			return 0;
		dev_err(dev, "DT properties 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;

	return 0;
}

static const struct of_device_id of_gpio_fan_match[] = {
	{ .compatible = "gpio-fan", },
	{},
};
MODULE_DEVICE_TABLE(of, of_gpio_fan_match);
#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);

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

#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->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);
#ifdef CONFIG_OF_GPIO
	/* Optional cooling device register for Device tree platforms */
	fan_data->cdev = thermal_of_cooling_device_register(pdev->dev.of_node,
							    "gpio-fan",
							    fan_data,
							    &gpio_fan_cool_ops);
#else /* CONFIG_OF_GPIO */
	/* Optional cooling device register for non Device tree platforms */
	fan_data->cdev = thermal_cooling_device_register("gpio-fan", fan_data,
							 &gpio_fan_cool_ops);
#endif /* CONFIG_OF_GPIO */

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

	return 0;
}

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

	if (!IS_ERR(fan_data->cdev))
		thermal_cooling_device_unregister(fan_data->cdev);

	if (fan_data->ctrl)
		set_fan_speed(fan_data, 0);

	return 0;
}

static void gpio_fan_shutdown(struct platform_device *pdev)
{
	gpio_fan_remove(pdev);
}

#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,
	.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>
b5cf88e4	37	#include <linux/thermal.h>
d6fe1360 SG	38
	39	struct gpio_fan_data {
	40	struct platform_device *pdev;
	41	struct device *hwmon_dev;
b5cf88e4 NM	42	/* Cooling device if any */
b5cf88e4 NM	43	struct thermal_cooling_device *cdev;
d6fe1360 SG	44	struct mutex lock; /* lock GPIOs operations. */
	45	int num_ctrl;
	46	unsigned *ctrl;
	47	int num_speed;
	48	struct gpio_fan_speed *speed;
	49	int speed_index;
6d20a6c0	50	#ifdef CONFIG_PM_SLEEP
d6fe1360 SG	51	int resume_speed;
	52	#endif
	53	bool pwm_enable;
	54	struct gpio_fan_alarm *alarm;
	55	struct work_struct alarm_work;
	56	};
	57
	58	/*
	59	* Alarm GPIO.
	60	*/
	61
	62	static void fan_alarm_notify(struct work_struct *ws)
	63	{
	64	struct gpio_fan_data *fan_data =
	65	container_of(ws, struct gpio_fan_data, alarm_work);
	66
	67	sysfs_notify(&fan_data->pdev->dev.kobj, NULL, "fan1_alarm");
	68	kobject_uevent(&fan_data->pdev->dev.kobj, KOBJ_CHANGE);
	69	}
	70
	71	static irqreturn_t fan_alarm_irq_handler(int irq, void *dev_id)
	72	{
	73	struct gpio_fan_data *fan_data = dev_id;
	74
	75	schedule_work(&fan_data->alarm_work);
	76
	77	return IRQ_NONE;
	78	}
	79
	80	static ssize_t show_fan_alarm(struct device *dev,
	81	struct device_attribute attr, char buf)
	82	{
	83	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	84	struct gpio_fan_alarm *alarm = fan_data->alarm;
52a95c11	85	int value = gpio_get_value_cansleep(alarm->gpio);
d6fe1360 SG	86
	87	if (alarm->active_low)
	88	value = !value;
	89
	90	return sprintf(buf, "%d\n", value);
	91	}
	92
	93	static DEVICE_ATTR(fan1_alarm, S_IRUGO, show_fan_alarm, NULL);
	94
	95	static int fan_alarm_init(struct gpio_fan_data *fan_data,
	96	struct gpio_fan_alarm *alarm)
	97	{
	98	int err;
	99	int alarm_irq;
	100	struct platform_device *pdev = fan_data->pdev;
	101
	102	fan_data->alarm = alarm;
	103
d00985f3	104	err = devm_gpio_request(&pdev->dev, alarm->gpio, "GPIO fan alarm");
d6fe1360 SG	105	if (err)
	106	return err;
	107
	108	err = gpio_direction_input(alarm->gpio);
	109	if (err)
d00985f3	110	return err;
d6fe1360	111
d6fe1360 SG	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	return err;
	125	}
	126
d6fe1360 SG	127	/*
	128	* Control GPIOs.
	129	*/
	130
	131	/* Must be called with fan_data->lock held, except during initialization. */
	132	static void __set_fan_ctrl(struct gpio_fan_data *fan_data, int ctrl_val)
	133	{
	134	int i;
	135
	136	for (i = 0; i < fan_data->num_ctrl; i++)
52a95c11	137	gpio_set_value_cansleep(fan_data->ctrl[i], (ctrl_val >> i) & 1);
d6fe1360 SG	138	}
	139
	140	static int __get_fan_ctrl(struct gpio_fan_data *fan_data)
	141	{
	142	int i;
	143	int ctrl_val = 0;
	144
	145	for (i = 0; i < fan_data->num_ctrl; i++) {
	146	int value;
	147
52a95c11	148	value = gpio_get_value_cansleep(fan_data->ctrl[i]);
d6fe1360 SG	149	ctrl_val \|= (value << i);
	150	}
	151	return ctrl_val;
	152	}
	153
	154	/* Must be called with fan_data->lock held, except during initialization. */
	155	static void set_fan_speed(struct gpio_fan_data *fan_data, int speed_index)
	156	{
	157	if (fan_data->speed_index == speed_index)
	158	return;
	159
	160	__set_fan_ctrl(fan_data, fan_data->speed[speed_index].ctrl_val);
	161	fan_data->speed_index = speed_index;
	162	}
	163
	164	static int get_fan_speed_index(struct gpio_fan_data *fan_data)
	165	{
	166	int ctrl_val = __get_fan_ctrl(fan_data);
	167	int i;
	168
	169	for (i = 0; i < fan_data->num_speed; i++)
	170	if (fan_data->speed[i].ctrl_val == ctrl_val)
	171	return i;
	172
	173	dev_warn(&fan_data->pdev->dev,
	174	"missing speed array entry for GPIO value 0x%x\n", ctrl_val);
	175
c52ae3d2	176	return -ENODEV;
d6fe1360 SG	177	}
d6fe1360 SG	178
2565fb05	179	static int rpm_to_speed_index(struct gpio_fan_data *fan_data, unsigned long rpm)
d6fe1360 SG	180	{
	181	struct gpio_fan_speed *speed = fan_data->speed;
	182	int i;
	183
	184	for (i = 0; i < fan_data->num_speed; i++)
	185	if (speed[i].rpm >= rpm)
	186	return i;
	187
	188	return fan_data->num_speed - 1;
	189	}
	190
	191	static ssize_t show_pwm(struct device *dev,
	192	struct device_attribute attr, char buf)
	193	{
	194	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	195	u8 pwm = fan_data->speed_index * 255 / (fan_data->num_speed - 1);
	196
	197	return sprintf(buf, "%d\n", pwm);
	198	}
	199
	200	static ssize_t set_pwm(struct device dev, struct device_attribute attr,
	201	const char *buf, size_t count)
	202	{
	203	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	204	unsigned long pwm;
	205	int speed_index;
	206	int ret = count;
	207
179c4fdb	208	if (kstrtoul(buf, 10, &pwm) \|\| pwm > 255)
d6fe1360 SG	209	return -EINVAL;
	210
	211	mutex_lock(&fan_data->lock);
	212
	213	if (!fan_data->pwm_enable) {
	214	ret = -EPERM;
	215	goto exit_unlock;
	216	}
	217
	218	speed_index = DIV_ROUND_UP(pwm * (fan_data->num_speed - 1), 255);
	219	set_fan_speed(fan_data, speed_index);
	220
	221	exit_unlock:
	222	mutex_unlock(&fan_data->lock);
	223
	224	return ret;
	225	}
	226
	227	static ssize_t show_pwm_enable(struct device *dev,
	228	struct device_attribute attr, char buf)
	229	{
	230	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	231
	232	return sprintf(buf, "%d\n", fan_data->pwm_enable);
	233	}
	234
	235	static ssize_t set_pwm_enable(struct device dev, struct device_attribute attr,
	236	const char *buf, size_t count)
	237	{
	238	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	239	unsigned long val;
	240
179c4fdb	241	if (kstrtoul(buf, 10, &val) \|\| val > 1)
d6fe1360 SG	242	return -EINVAL;
	243
	244	if (fan_data->pwm_enable == val)
	245	return count;
	246
	247	mutex_lock(&fan_data->lock);
	248
	249	fan_data->pwm_enable = val;
	250
	251	/* Disable manual control mode: set fan at full speed. */
	252	if (val == 0)
	253	set_fan_speed(fan_data, fan_data->num_speed - 1);
	254
	255	mutex_unlock(&fan_data->lock);
	256
	257	return count;
	258	}
	259
	260	static ssize_t show_pwm_mode(struct device *dev,
	261	struct device_attribute attr, char buf)
	262	{
	263	return sprintf(buf, "0\n");
	264	}
	265
	266	static ssize_t show_rpm_min(struct device *dev,
	267	struct device_attribute attr, char buf)
	268	{
	269	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	270
	271	return sprintf(buf, "%d\n", fan_data->speed[0].rpm);
	272	}
	273
	274	static ssize_t show_rpm_max(struct device *dev,
	275	struct device_attribute attr, char buf)
	276	{
	277	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	278
	279	return sprintf(buf, "%d\n",
	280	fan_data->speed[fan_data->num_speed - 1].rpm);
	281	}
	282
	283	static ssize_t show_rpm(struct device *dev,
	284	struct device_attribute attr, char buf)
	285	{
	286	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	287
	288	return sprintf(buf, "%d\n", fan_data->speed[fan_data->speed_index].rpm);
	289	}
	290
	291	static ssize_t set_rpm(struct device dev, struct device_attribute attr,
	292	const char *buf, size_t count)
	293	{
	294	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
	295	unsigned long rpm;
	296	int ret = count;
	297
179c4fdb	298	if (kstrtoul(buf, 10, &rpm))
d6fe1360 SG	299	return -EINVAL;
	300
	301	mutex_lock(&fan_data->lock);
	302
	303	if (!fan_data->pwm_enable) {
	304	ret = -EPERM;
	305	goto exit_unlock;
	306	}
	307
	308	set_fan_speed(fan_data, rpm_to_speed_index(fan_data, rpm));
	309
	310	exit_unlock:
	311	mutex_unlock(&fan_data->lock);
	312
	313	return ret;
	314	}
	315
	316	static DEVICE_ATTR(pwm1, S_IRUGO \| S_IWUSR, show_pwm, set_pwm);
	317	static DEVICE_ATTR(pwm1_enable, S_IRUGO \| S_IWUSR,
	318	show_pwm_enable, set_pwm_enable);
	319	static DEVICE_ATTR(pwm1_mode, S_IRUGO, show_pwm_mode, NULL);
	320	static DEVICE_ATTR(fan1_min, S_IRUGO, show_rpm_min, NULL);
	321	static DEVICE_ATTR(fan1_max, S_IRUGO, show_rpm_max, NULL);
	322	static DEVICE_ATTR(fan1_input, S_IRUGO, show_rpm, NULL);
	323	static DEVICE_ATTR(fan1_target, S_IRUGO \| S_IWUSR, show_rpm, set_rpm);
	324
c81cc5a4 GR	325	static umode_t gpio_fan_is_visible(struct kobject *kobj,
	326	struct attribute *attr, int index)
	327	{
	328	struct device *dev = container_of(kobj, struct device, kobj);
	329	struct gpio_fan_data *data = dev_get_drvdata(dev);
	330
7258a125	331	if (index == 0 && !data->alarm)
c81cc5a4	332	return 0;
7258a125	333	if (index > 0 && !data->ctrl)
c81cc5a4 GR	334	return 0;
	335
	336	return attr->mode;
	337	}
	338
	339	static struct attribute *gpio_fan_attributes[] = {
7258a125 GR	340	&dev_attr_fan1_alarm.attr, /* 0 */
7258a125 GR	341	&dev_attr_pwm1.attr, /* 1 */
d6fe1360 SG	342	&dev_attr_pwm1_enable.attr,
	343	&dev_attr_pwm1_mode.attr,
	344	&dev_attr_fan1_input.attr,
	345	&dev_attr_fan1_target.attr,
	346	&dev_attr_fan1_min.attr,
	347	&dev_attr_fan1_max.attr,
	348	NULL
	349	};
	350
c81cc5a4 GR	351	static const struct attribute_group gpio_fan_group = {
	352	.attrs = gpio_fan_attributes,
	353	.is_visible = gpio_fan_is_visible,
d6fe1360 SG	354	};
d6fe1360 SG	355
7258a125 GR	356	static const struct attribute_group *gpio_fan_groups[] = {
	357	&gpio_fan_group,
	358	NULL
	359	};
	360
d6fe1360 SG	361	static int fan_ctrl_init(struct gpio_fan_data *fan_data,
	362	struct gpio_fan_platform_data *pdata)
	363	{
	364	struct platform_device *pdev = fan_data->pdev;
	365	int num_ctrl = pdata->num_ctrl;
	366	unsigned *ctrl = pdata->ctrl;
	367	int i, err;
	368
	369	for (i = 0; i < num_ctrl; i++) {
d00985f3 GR	370	err = devm_gpio_request(&pdev->dev, ctrl[i],
d00985f3 GR	371	"GPIO fan control");
d6fe1360	372	if (err)
d00985f3	373	return err;
d6fe1360	374
52a95c11 NM	375	err = gpio_direction_output(ctrl[i],
52a95c11 NM	376	gpio_get_value_cansleep(ctrl[i]));
d00985f3 GR	377	if (err)
d00985f3 GR	378	return err;
d6fe1360 SG	379	}
d6fe1360 SG	380
d6fe1360 SG	381	fan_data->num_ctrl = num_ctrl;
	382	fan_data->ctrl = ctrl;
	383	fan_data->num_speed = pdata->num_speed;
	384	fan_data->speed = pdata->speed;
	385	fan_data->pwm_enable = true; /* Enable manual fan speed control. */
	386	fan_data->speed_index = get_fan_speed_index(fan_data);
d00985f3	387	if (fan_data->speed_index < 0)
c52ae3d2	388	return fan_data->speed_index;
d6fe1360	389
c81cc5a4	390	return 0;
d6fe1360 SG	391	}
d6fe1360 SG	392
b5cf88e4 NM	393	static int gpio_fan_get_max_state(struct thermal_cooling_device *cdev,
	394	unsigned long *state)
	395	{
	396	struct gpio_fan_data *fan_data = cdev->devdata;
	397
	398	if (!fan_data)
	399	return -EINVAL;
	400
	401	*state = fan_data->num_speed - 1;
	402	return 0;
	403	}
	404
	405	static int gpio_fan_get_cur_state(struct thermal_cooling_device *cdev,
	406	unsigned long *state)
	407	{
	408	struct gpio_fan_data *fan_data = cdev->devdata;
	409	int r;
	410
	411	if (!fan_data)
	412	return -EINVAL;
	413
	414	r = get_fan_speed_index(fan_data);
	415	if (r < 0)
	416	return r;
	417
	418	*state = r;
	419	return 0;
	420	}
	421
	422	static int gpio_fan_set_cur_state(struct thermal_cooling_device *cdev,
	423	unsigned long state)
	424	{
	425	struct gpio_fan_data *fan_data = cdev->devdata;
	426
	427	if (!fan_data)
	428	return -EINVAL;
	429
	430	set_fan_speed(fan_data, state);
	431	return 0;
	432	}
	433
	434	static const struct thermal_cooling_device_ops gpio_fan_cool_ops = {
	435	.get_max_state = gpio_fan_get_max_state,
	436	.get_cur_state = gpio_fan_get_cur_state,
	437	.set_cur_state = gpio_fan_set_cur_state,
	438	};
	439
55fb8b06 JL	440	#ifdef CONFIG_OF_GPIO
	441	/*
	442	* Translate OpenFirmware node properties into platform_data
	443	*/
	444	static int gpio_fan_get_of_pdata(struct device *dev,
	445	struct gpio_fan_platform_data *pdata)
	446	{
	447	struct device_node *node;
	448	struct gpio_fan_speed *speed;
	449	unsigned *ctrl;
	450	unsigned i;
	451	u32 u;
	452	struct property *prop;
	453	const __be32 *p;
	454
	455	node = dev->of_node;
	456
73ef85f4 SG	457	/* Alarm GPIO if one exists */
	458	if (of_gpio_named_count(node, "alarm-gpios") > 0) {
	459	struct gpio_fan_alarm *alarm;
	460	int val;
	461	enum of_gpio_flags flags;
	462
	463	alarm = devm_kzalloc(dev, sizeof(struct gpio_fan_alarm),
	464	GFP_KERNEL);
	465	if (!alarm)
	466	return -ENOMEM;
	467
	468	val = of_get_named_gpio_flags(node, "alarm-gpios", 0, &flags);
	469	if (val < 0)
	470	return val;
	471	alarm->gpio = val;
	472	alarm->active_low = flags & OF_GPIO_ACTIVE_LOW;
	473
	474	pdata->alarm = alarm;
	475	}
	476
55fb8b06 JL	477	/* Fill GPIO pin array */
55fb8b06 JL	478	pdata->num_ctrl = of_gpio_count(node);
e80beb27	479	if (pdata->num_ctrl <= 0) {
73ef85f4 SG	480	if (pdata->alarm)
	481	return 0;
	482	dev_err(dev, "DT properties empty / missing");
55fb8b06 JL	483	return -ENODEV;
	484	}
	485	ctrl = devm_kzalloc(dev, pdata->num_ctrl * sizeof(unsigned),
	486	GFP_KERNEL);
	487	if (!ctrl)
	488	return -ENOMEM;
	489	for (i = 0; i < pdata->num_ctrl; i++) {
	490	int val;
	491
	492	val = of_get_gpio(node, i);
	493	if (val < 0)
	494	return val;
	495	ctrl[i] = val;
	496	}
	497	pdata->ctrl = ctrl;
	498
	499	/* Get number of RPM/ctrl_val pairs in speed map */
	500	prop = of_find_property(node, "gpio-fan,speed-map", &i);
	501	if (!prop) {
	502	dev_err(dev, "gpio-fan,speed-map DT property missing");
	503	return -ENODEV;
	504	}
	505	i = i / sizeof(u32);
	506	if (i == 0 \|\| i & 1) {
	507	dev_err(dev, "gpio-fan,speed-map contains zero/odd number of entries");
	508	return -ENODEV;
	509	}
	510	pdata->num_speed = i / 2;
	511
	512	/*
	513	* Populate speed map
	514	* Speed map is in the form <RPM ctrl_val RPM ctrl_val ...>
	515	* this needs splitting into pairs to create gpio_fan_speed structs
	516	*/
	517	speed = devm_kzalloc(dev,
	518	pdata->num_speed * sizeof(struct gpio_fan_speed),
	519	GFP_KERNEL);
	520	if (!speed)
	521	return -ENOMEM;
	522	p = NULL;
	523	for (i = 0; i < pdata->num_speed; i++) {
	524	p = of_prop_next_u32(prop, p, &u);
	525	if (!p)
	526	return -ENODEV;
	527	speed[i].rpm = u;
	528	p = of_prop_next_u32(prop, p, &u);
	529	if (!p)
	530	return -ENODEV;
	531	speed[i].ctrl_val = u;
	532	}
	533	pdata->speed = speed;
	534
55fb8b06 JL	535	return 0;
	536	}
	537
6de709c5	538	static const struct of_device_id of_gpio_fan_match[] = {
55fb8b06 JL	539	{ .compatible = "gpio-fan", },
	540	{},
	541	};
fe515288	542	MODULE_DEVICE_TABLE(of, of_gpio_fan_match);
55fb8b06 JL	543	#endif /* CONFIG_OF_GPIO */
55fb8b06 JL	544
6c931ae1	545	static int gpio_fan_probe(struct platform_device *pdev)
d6fe1360 SG	546	{
	547	int err;
	548	struct gpio_fan_data *fan_data;
a8b3a3a5	549	struct gpio_fan_platform_data *pdata = dev_get_platdata(&pdev->dev);
d6fe1360	550
b5cf88e4 NM	551	fan_data = devm_kzalloc(&pdev->dev, sizeof(struct gpio_fan_data),
	552	GFP_KERNEL);
	553	if (!fan_data)
	554	return -ENOMEM;
	555
55fb8b06 JL	556	#ifdef CONFIG_OF_GPIO
	557	if (!pdata) {
	558	pdata = devm_kzalloc(&pdev->dev,
	559	sizeof(struct gpio_fan_platform_data),
	560	GFP_KERNEL);
	561	if (!pdata)
	562	return -ENOMEM;
	563
	564	err = gpio_fan_get_of_pdata(&pdev->dev, pdata);
	565	if (err)
	566	return err;
	567	}
	568	#else /* CONFIG_OF_GPIO */
d6fe1360 SG	569	if (!pdata)
d6fe1360 SG	570	return -EINVAL;
55fb8b06	571	#endif /* CONFIG_OF_GPIO */
d6fe1360	572
d6fe1360 SG	573	fan_data->pdev = pdev;
	574	platform_set_drvdata(pdev, fan_data);
	575	mutex_init(&fan_data->lock);
	576
	577	/* Configure alarm GPIO if available. */
	578	if (pdata->alarm) {
	579	err = fan_alarm_init(fan_data, pdata->alarm);
	580	if (err)
d00985f3	581	return err;
d6fe1360 SG	582	}
	583
	584	/* Configure control GPIOs if available. */
	585	if (pdata->ctrl && pdata->num_ctrl > 0) {
c81cc5a4 GR	586	if (!pdata->speed \|\| pdata->num_speed <= 1)
c81cc5a4 GR	587	return -EINVAL;
d6fe1360 SG	588	err = fan_ctrl_init(fan_data, pdata);
d6fe1360 SG	589	if (err)
c81cc5a4	590	return err;
d6fe1360 SG	591	}
d6fe1360 SG	592
d6fe1360	593	/* Make this driver part of hwmon class. */
49153b09 AL	594	fan_data->hwmon_dev =
	595	devm_hwmon_device_register_with_groups(&pdev->dev,
	596	"gpio_fan", fan_data,
	597	gpio_fan_groups);
7258a125 GR	598	if (IS_ERR(fan_data->hwmon_dev))
7258a125 GR	599	return PTR_ERR(fan_data->hwmon_dev);
e76ea261 NM	600	#ifdef CONFIG_OF_GPIO
	601	/* Optional cooling device register for Device tree platforms */
	602	fan_data->cdev = thermal_of_cooling_device_register(pdev->dev.of_node,
	603	"gpio-fan",
	604	fan_data,
	605	&gpio_fan_cool_ops);
	606	#else /* CONFIG_OF_GPIO */
	607	/* Optional cooling device register for non Device tree platforms */
	608	fan_data->cdev = thermal_cooling_device_register("gpio-fan", fan_data,
	609	&gpio_fan_cool_ops);
	610	#endif /* CONFIG_OF_GPIO */
d6fe1360 SG	611
	612	dev_info(&pdev->dev, "GPIO fan initialized\n");
	613
	614	return 0;
d6fe1360 SG	615	}
d6fe1360 SG	616
b5cf88e4	617	static int gpio_fan_remove(struct platform_device *pdev)
b95579cd	618	{
b5cf88e4 NM	619	struct gpio_fan_data *fan_data = platform_get_drvdata(pdev);
	620
	621	if (!IS_ERR(fan_data->cdev))
	622	thermal_cooling_device_unregister(fan_data->cdev);
b95579cd NM	623
	624	if (fan_data->ctrl)
	625	set_fan_speed(fan_data, 0);
b5cf88e4 NM	626
	627	return 0;
	628	}
	629
	630	static void gpio_fan_shutdown(struct platform_device *pdev)
	631	{
	632	gpio_fan_remove(pdev);
b95579cd NM	633	}
b95579cd NM	634
6d20a6c0 RW	635	#ifdef CONFIG_PM_SLEEP
6d20a6c0 RW	636	static int gpio_fan_suspend(struct device *dev)
d6fe1360	637	{
6d20a6c0	638	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
d6fe1360 SG	639
	640	if (fan_data->ctrl) {
	641	fan_data->resume_speed = fan_data->speed_index;
	642	set_fan_speed(fan_data, 0);
	643	}
	644
	645	return 0;
	646	}
	647
6d20a6c0	648	static int gpio_fan_resume(struct device *dev)
d6fe1360	649	{
6d20a6c0	650	struct gpio_fan_data *fan_data = dev_get_drvdata(dev);
d6fe1360 SG	651
	652	if (fan_data->ctrl)
	653	set_fan_speed(fan_data, fan_data->resume_speed);
	654
	655	return 0;
	656	}
6d20a6c0 RW	657
6d20a6c0 RW	658	static SIMPLE_DEV_PM_OPS(gpio_fan_pm, gpio_fan_suspend, gpio_fan_resume);
24f9c539	659	#define GPIO_FAN_PM (&gpio_fan_pm)
d6fe1360	660	#else
6d20a6c0	661	#define GPIO_FAN_PM NULL
d6fe1360 SG	662	#endif
	663
	664	static struct platform_driver gpio_fan_driver = {
	665	.probe = gpio_fan_probe,
b5cf88e4	666	.remove = gpio_fan_remove,
b95579cd	667	.shutdown = gpio_fan_shutdown,
d6fe1360 SG	668	.driver = {
d6fe1360 SG	669	.name = "gpio-fan",
6d20a6c0	670	.pm = GPIO_FAN_PM,
eaa7cc60	671	#ifdef CONFIG_OF_GPIO
55fb8b06	672	.of_match_table = of_match_ptr(of_gpio_fan_match),
eaa7cc60	673	#endif
d6fe1360 SG	674	},
	675	};
	676
25a236a5	677	module_platform_driver(gpio_fan_driver);
d6fe1360 SG	678
	679	MODULE_AUTHOR("Simon Guinot <sguinot@lacie.com>");
	680	MODULE_DESCRIPTION("GPIO FAN driver");
	681	MODULE_LICENSE("GPL");
	682	MODULE_ALIAS("platform:gpio-fan");