1 // SPDX-License-Identifier: GPL-2.0-or-later
3  * gpio-fan.c - Hwmon driver for fans connected to GPIO lines.
34 	struct mutex		lock; /* lock GPIOs operations. */
36 	struct gpio_desc	**gpios;  member
55 	sysfs_notify(&fan_data->hwmon_dev->kobj, NULL, "fan1_alarm");  in fan_alarm_notify()
56 	kobject_uevent(&fan_data->hwmon_dev->kobj, KOBJ_CHANGE);  in fan_alarm_notify()
63 	schedule_work(&fan_data->alarm_work);  in fan_alarm_irq_handler()
74 		       gpiod_get_value_cansleep(fan_data->alarm_gpio));  in fan1_alarm_show()
82 	struct device *dev = fan_data->dev;  in fan_alarm_init()
88 	alarm_irq = gpiod_to_irq(fan_data->alarm_gpio);  in fan_alarm_init()
92 	INIT_WORK(&fan_data->alarm_work, fan_alarm_notify);  in fan_alarm_init()
99  * Control GPIOs.
102 /* Must be called with fan_data->lock held, except during initialization. */
107 	for (i = 0; i < fan_data->num_gpios; i++)  in __set_fan_ctrl()
108 		gpiod_set_value_cansleep(fan_data->gpios[i],  in __set_fan_ctrl()
117 	for (i = 0; i < fan_data->num_gpios; i++) {  in __get_fan_ctrl()
120 		value = gpiod_get_value_cansleep(fan_data->gpios[i]);  in __get_fan_ctrl()
126 /* Must be called with fan_data->lock held, except during initialization. */
129 	if (fan_data->speed_index == speed_index)  in set_fan_speed()
132 	__set_fan_ctrl(fan_data, fan_data->speed[speed_index].ctrl_val);  in set_fan_speed()
133 	fan_data->speed_index = speed_index;  in set_fan_speed()
141 	for (i = 0; i < fan_data->num_speed; i++)  in get_fan_speed_index()
142 		if (fan_data->speed[i].ctrl_val == ctrl_val)  in get_fan_speed_index()
145 	dev_warn(fan_data->dev,  in get_fan_speed_index()
148 	return -ENODEV;  in get_fan_speed_index()
153 	struct gpio_fan_speed *speed = fan_data->speed;  in rpm_to_speed_index()
156 	for (i = 0; i < fan_data->num_speed; i++)  in rpm_to_speed_index()
160 	return fan_data->num_speed - 1;  in rpm_to_speed_index()
167 	u8 pwm = fan_data->speed_index * 255 / (fan_data->num_speed - 1);  in pwm1_show()
181 		return -EINVAL;  in pwm1_store()
183 	mutex_lock(&fan_data->lock);  in pwm1_store()
185 	if (!fan_data->pwm_enable) {  in pwm1_store()
186 		ret = -EPERM;  in pwm1_store()
190 	speed_index = DIV_ROUND_UP(pwm * (fan_data->num_speed - 1), 255);  in pwm1_store()
194 	mutex_unlock(&fan_data->lock);  in pwm1_store()
204 	return sprintf(buf, "%d\n", fan_data->pwm_enable);  in pwm1_enable_show()
215 		return -EINVAL;  in pwm1_enable_store()
217 	if (fan_data->pwm_enable == val)  in pwm1_enable_store()
220 	mutex_lock(&fan_data->lock);  in pwm1_enable_store()
222 	fan_data->pwm_enable = val;  in pwm1_enable_store()
226 		set_fan_speed(fan_data, fan_data->num_speed - 1);  in pwm1_enable_store()
228 	mutex_unlock(&fan_data->lock);  in pwm1_enable_store()
244 	return sprintf(buf, "%d\n", fan_data->speed[0].rpm);  in fan1_min_show()
253 		       fan_data->speed[fan_data->num_speed - 1].rpm);  in fan1_max_show()
261 	return sprintf(buf, "%d\n", fan_data->speed[fan_data->speed_index].rpm);  in fan1_input_show()
272 		return -EINVAL;  in set_rpm()
274 	mutex_lock(&fan_data->lock);  in set_rpm()
276 	if (!fan_data->pwm_enable) {  in set_rpm()
277 		ret = -EPERM;  in set_rpm()
284 	mutex_unlock(&fan_data->lock);  in set_rpm()
301 	struct gpio_fan_data *data = dev_get_drvdata(dev);  in gpio_fan_is_visible()  local
303 	if (index == 0 && !data->alarm_gpio)  in gpio_fan_is_visible()
305 	if (index > 0 && !data->gpios)  in gpio_fan_is_visible()
308 	return attr->mode;  in gpio_fan_is_visible()
335 	int num_gpios = fan_data->num_gpios;  in fan_ctrl_init()
336 	struct gpio_desc **gpios = fan_data->gpios;  in fan_ctrl_init()  local
346 		err = gpiod_direction_output(gpios[i],  in fan_ctrl_init()
347 					gpiod_get_value_cansleep(gpios[i]));  in fan_ctrl_init()
352 	fan_data->pwm_enable = true; /* Enable manual fan speed control. */  in fan_ctrl_init()
353 	fan_data->speed_index = get_fan_speed_index(fan_data);  in fan_ctrl_init()
354 	if (fan_data->speed_index < 0)  in fan_ctrl_init()
355 		return fan_data->speed_index;  in fan_ctrl_init()
363 	struct gpio_fan_data *fan_data = cdev->devdata;  in gpio_fan_get_max_state()
366 		return -EINVAL;  in gpio_fan_get_max_state()
368 	*state = fan_data->num_speed - 1;  in gpio_fan_get_max_state()
375 	struct gpio_fan_data *fan_data = cdev->devdata;  in gpio_fan_get_cur_state()
378 		return -EINVAL;  in gpio_fan_get_cur_state()
380 	*state = fan_data->speed_index;  in gpio_fan_get_cur_state()
387 	struct gpio_fan_data *fan_data = cdev->devdata;  in gpio_fan_set_cur_state()
390 		return -EINVAL;  in gpio_fan_set_cur_state()
392 	if (state >= fan_data->num_speed)  in gpio_fan_set_cur_state()
393 		return -EINVAL;  in gpio_fan_set_cur_state()
411 	struct device *dev = fan_data->dev;  in gpio_fan_get_of_data()
412 	struct device_node *np = dev->of_node;  in gpio_fan_get_of_data()
413 	struct gpio_desc **gpios;  in gpio_fan_get_of_data()  local
420 	fan_data->alarm_gpio = devm_gpiod_get_optional(dev, "alarm", GPIOD_IN);  in gpio_fan_get_of_data()
421 	if (IS_ERR(fan_data->alarm_gpio))  in gpio_fan_get_of_data()
422 		return PTR_ERR(fan_data->alarm_gpio);  in gpio_fan_get_of_data()
425 	fan_data->num_gpios = gpiod_count(dev, NULL);  in gpio_fan_get_of_data()
426 	if (fan_data->num_gpios <= 0) {  in gpio_fan_get_of_data()
427 		if (fan_data->alarm_gpio)  in gpio_fan_get_of_data()
430 		return -ENODEV;  in gpio_fan_get_of_data()
432 	gpios = devm_kcalloc(dev,  in gpio_fan_get_of_data()
433 			     fan_data->num_gpios, sizeof(struct gpio_desc *),  in gpio_fan_get_of_data()
435 	if (!gpios)  in gpio_fan_get_of_data()
436 		return -ENOMEM;  in gpio_fan_get_of_data()
437 	for (i = 0; i < fan_data->num_gpios; i++) {  in gpio_fan_get_of_data()
438 		gpios[i] = devm_gpiod_get_index(dev, NULL, i, GPIOD_ASIS);  in gpio_fan_get_of_data()
439 		if (IS_ERR(gpios[i]))  in gpio_fan_get_of_data()
440 			return PTR_ERR(gpios[i]);  in gpio_fan_get_of_data()
442 	fan_data->gpios = gpios;  in gpio_fan_get_of_data()
445 	prop = of_find_property(np, "gpio-fan,speed-map", &i);  in gpio_fan_get_of_data()
447 		dev_err(dev, "gpio-fan,speed-map DT property missing");  in gpio_fan_get_of_data()
448 		return -ENODEV;  in gpio_fan_get_of_data()
452 		dev_err(dev, "gpio-fan,speed-map contains zero/odd number of entries");  in gpio_fan_get_of_data()
453 		return -ENODEV;  in gpio_fan_get_of_data()
455 	fan_data->num_speed = i / 2;  in gpio_fan_get_of_data()
463 			fan_data->num_speed, sizeof(struct gpio_fan_speed),  in gpio_fan_get_of_data()
466 		return -ENOMEM;  in gpio_fan_get_of_data()
468 	for (i = 0; i < fan_data->num_speed; i++) {  in gpio_fan_get_of_data()
471 			return -ENODEV;  in gpio_fan_get_of_data()
475 			return -ENODEV;  in gpio_fan_get_of_data()
478 	fan_data->speed = speed;  in gpio_fan_get_of_data()
484 	{ .compatible = "gpio-fan", },
489 static void gpio_fan_stop(void *data)  in gpio_fan_stop()  argument
491 	set_fan_speed(data, 0);  in gpio_fan_stop()
498 	struct device *dev = &pdev->dev;  in gpio_fan_probe()
499 	struct device_node *np = dev->of_node;  in gpio_fan_probe()
504 		return -ENOMEM;  in gpio_fan_probe()
506 	fan_data->dev = dev;  in gpio_fan_probe()
512 	mutex_init(&fan_data->lock);  in gpio_fan_probe()
514 	/* Configure control GPIOs if available. */  in gpio_fan_probe()
515 	if (fan_data->gpios && fan_data->num_gpios > 0) {  in gpio_fan_probe()
516 		if (!fan_data->speed || fan_data->num_speed <= 1)  in gpio_fan_probe()
517 			return -EINVAL;  in gpio_fan_probe()
527 	fan_data->hwmon_dev =  in gpio_fan_probe()
531 	if (IS_ERR(fan_data->hwmon_dev))  in gpio_fan_probe()
532 		return PTR_ERR(fan_data->hwmon_dev);  in gpio_fan_probe()
535 	if (fan_data->alarm_gpio) {  in gpio_fan_probe()
542 	fan_data->cdev = devm_thermal_of_cooling_device_register(dev, np,  in gpio_fan_probe()
543 				"gpio-fan", fan_data, &gpio_fan_cool_ops);  in gpio_fan_probe()
554 	if (fan_data->gpios)  in gpio_fan_shutdown()
562 	if (fan_data->gpios) {  in gpio_fan_suspend()
563 		fan_data->resume_speed = fan_data->speed_index;  in gpio_fan_suspend()
574 	if (fan_data->gpios)  in gpio_fan_resume()
575 		set_fan_speed(fan_data, fan_data->resume_speed);  in gpio_fan_resume()
586 		.name	= "gpio-fan",
597 MODULE_ALIAS("platform:gpio-fan");