1 // SPDX-License-Identifier: GPL-2.0-or-later
3  * gpio-fan.c - Hwmon driver for fans connected to GPIO lines.
39 	struct gpio_fan_speed	*speed;  member
56 	sysfs_notify(&fan_data->hwmon_dev->kobj, NULL, "fan1_alarm");  in fan_alarm_notify()
57 	kobject_uevent(&fan_data->hwmon_dev->kobj, KOBJ_CHANGE);  in fan_alarm_notify()
64 	schedule_work(&fan_data->alarm_work);  in fan_alarm_irq_handler()
75 		       gpiod_get_value_cansleep(fan_data->alarm_gpio));  in fan1_alarm_show()
83 	struct device *dev = fan_data->dev;  in fan_alarm_init()
89 	alarm_irq = gpiod_to_irq(fan_data->alarm_gpio);  in fan_alarm_init()
93 	INIT_WORK(&fan_data->alarm_work, fan_alarm_notify);  in fan_alarm_init()
103 /* Must be called with fan_data->lock held, except during initialization. */
108 	for (i = 0; i < fan_data->num_gpios; i++)  in __set_fan_ctrl()
109 		gpiod_set_value_cansleep(fan_data->gpios[i],  in __set_fan_ctrl()
118 	for (i = 0; i < fan_data->num_gpios; i++) {  in __get_fan_ctrl()
121 		value = gpiod_get_value_cansleep(fan_data->gpios[i]);  in __get_fan_ctrl()
127 /* Must be called with fan_data->lock held, except during initialization. */
130 	if (fan_data->speed_index == speed_index)  in set_fan_speed()
133 	__set_fan_ctrl(fan_data, fan_data->speed[speed_index].ctrl_val);  in set_fan_speed()
134 	fan_data->speed_index = speed_index;  in set_fan_speed()
142 	for (i = 0; i < fan_data->num_speed; i++)  in get_fan_speed_index()
143 		if (fan_data->speed[i].ctrl_val == ctrl_val)  in get_fan_speed_index()
146 	dev_warn(fan_data->dev,  in get_fan_speed_index()
147 		 "missing speed array entry for GPIO value 0x%x\n", ctrl_val);  in get_fan_speed_index()
149 	return -ENODEV;  in get_fan_speed_index()
154 	struct gpio_fan_speed *speed = fan_data->speed;  in rpm_to_speed_index()  local
157 	for (i = 0; i < fan_data->num_speed; i++)  in rpm_to_speed_index()
158 		if (speed[i].rpm >= rpm)  in rpm_to_speed_index()
161 	return fan_data->num_speed - 1;  in rpm_to_speed_index()
168 	u8 pwm = fan_data->speed_index * 255 / (fan_data->num_speed - 1);  in pwm1_show()
182 		return -EINVAL;  in pwm1_store()
184 	mutex_lock(&fan_data->lock);  in pwm1_store()
186 	if (!fan_data->pwm_enable) {  in pwm1_store()
187 		ret = -EPERM;  in pwm1_store()
191 	speed_index = DIV_ROUND_UP(pwm * (fan_data->num_speed - 1), 255);  in pwm1_store()
195 	mutex_unlock(&fan_data->lock);  in pwm1_store()
205 	return sprintf(buf, "%d\n", fan_data->pwm_enable);  in pwm1_enable_show()
216 		return -EINVAL;  in pwm1_enable_store()
218 	if (fan_data->pwm_enable == val)  in pwm1_enable_store()
221 	mutex_lock(&fan_data->lock);  in pwm1_enable_store()
223 	fan_data->pwm_enable = val;  in pwm1_enable_store()
225 	/* Disable manual control mode: set fan at full speed. */  in pwm1_enable_store()
227 		set_fan_speed(fan_data, fan_data->num_speed - 1);  in pwm1_enable_store()
229 	mutex_unlock(&fan_data->lock);  in pwm1_enable_store()
245 	return sprintf(buf, "%d\n", fan_data->speed[0].rpm);  in fan1_min_show()
254 		       fan_data->speed[fan_data->num_speed - 1].rpm);  in fan1_max_show()
262 	return sprintf(buf, "%d\n", fan_data->speed[fan_data->speed_index].rpm);  in fan1_input_show()
273 		return -EINVAL;  in set_rpm()
275 	mutex_lock(&fan_data->lock);  in set_rpm()
277 	if (!fan_data->pwm_enable) {  in set_rpm()
278 		ret = -EPERM;  in set_rpm()
285 	mutex_unlock(&fan_data->lock);  in set_rpm()
304 	if (index == 0 && !data->alarm_gpio)  in gpio_fan_is_visible()
306 	if (index > 0 && !data->gpios)  in gpio_fan_is_visible()
309 	return attr->mode;  in gpio_fan_is_visible()
336 	int num_gpios = fan_data->num_gpios;  in fan_ctrl_init()
337 	struct gpio_desc **gpios = fan_data->gpios;  in fan_ctrl_init()
345 		 * (no surprise changes in default fan speed).  in fan_ctrl_init()
353 	fan_data->pwm_enable = true; /* Enable manual fan speed control. */  in fan_ctrl_init()
354 	fan_data->speed_index = get_fan_speed_index(fan_data);  in fan_ctrl_init()
355 	if (fan_data->speed_index < 0)  in fan_ctrl_init()
356 		return fan_data->speed_index;  in fan_ctrl_init()
364 	struct gpio_fan_data *fan_data = cdev->devdata;  in gpio_fan_get_max_state()
367 		return -EINVAL;  in gpio_fan_get_max_state()
369 	*state = fan_data->num_speed - 1;  in gpio_fan_get_max_state()
376 	struct gpio_fan_data *fan_data = cdev->devdata;  in gpio_fan_get_cur_state()
379 		return -EINVAL;  in gpio_fan_get_cur_state()
381 	*state = fan_data->speed_index;  in gpio_fan_get_cur_state()
388 	struct gpio_fan_data *fan_data = cdev->devdata;  in gpio_fan_set_cur_state()
391 		return -EINVAL;  in gpio_fan_set_cur_state()
393 	if (state >= fan_data->num_speed)  in gpio_fan_set_cur_state()
394 		return -EINVAL;  in gpio_fan_set_cur_state()
411 	struct gpio_fan_speed *speed;  in gpio_fan_get_of_data()  local
412 	struct device *dev = fan_data->dev;  in gpio_fan_get_of_data()
413 	struct device_node *np = dev->of_node;  in gpio_fan_get_of_data()
421 	fan_data->alarm_gpio = devm_gpiod_get_optional(dev, "alarm", GPIOD_IN);  in gpio_fan_get_of_data()
422 	if (IS_ERR(fan_data->alarm_gpio))  in gpio_fan_get_of_data()
423 		return PTR_ERR(fan_data->alarm_gpio);  in gpio_fan_get_of_data()
426 	fan_data->num_gpios = gpiod_count(dev, NULL);  in gpio_fan_get_of_data()
427 	if (fan_data->num_gpios <= 0) {  in gpio_fan_get_of_data()
428 		if (fan_data->alarm_gpio)  in gpio_fan_get_of_data()
431 		return -ENODEV;  in gpio_fan_get_of_data()
434 			     fan_data->num_gpios, sizeof(struct gpio_desc *),  in gpio_fan_get_of_data()
437 		return -ENOMEM;  in gpio_fan_get_of_data()
438 	for (i = 0; i < fan_data->num_gpios; i++) {  in gpio_fan_get_of_data()
443 	fan_data->gpios = gpios;  in gpio_fan_get_of_data()
445 	/* Get number of RPM/ctrl_val pairs in speed map */  in gpio_fan_get_of_data()
446 	prop = of_find_property(np, "gpio-fan,speed-map", &i);  in gpio_fan_get_of_data()
448 		dev_err(dev, "gpio-fan,speed-map DT property missing");  in gpio_fan_get_of_data()
449 		return -ENODEV;  in gpio_fan_get_of_data()
453 		dev_err(dev, "gpio-fan,speed-map contains zero/odd number of entries");  in gpio_fan_get_of_data()
454 		return -ENODEV;  in gpio_fan_get_of_data()
456 	fan_data->num_speed = i / 2;  in gpio_fan_get_of_data()
459 	 * Populate speed map  in gpio_fan_get_of_data()
460 	 * Speed map is in the form <RPM ctrl_val RPM ctrl_val ...>  in gpio_fan_get_of_data()
463 	speed = devm_kcalloc(dev,  in gpio_fan_get_of_data()
464 			fan_data->num_speed, sizeof(struct gpio_fan_speed),  in gpio_fan_get_of_data()
466 	if (!speed)  in gpio_fan_get_of_data()
467 		return -ENOMEM;  in gpio_fan_get_of_data()
469 	for (i = 0; i < fan_data->num_speed; i++) {  in gpio_fan_get_of_data()
472 			return -ENODEV;  in gpio_fan_get_of_data()
473 		speed[i].rpm = u;  in gpio_fan_get_of_data()
476 			return -ENODEV;  in gpio_fan_get_of_data()
477 		speed[i].ctrl_val = u;  in gpio_fan_get_of_data()
479 	fan_data->speed = speed;  in gpio_fan_get_of_data()
485 	{ .compatible = "gpio-fan", },
499 	struct device *dev = &pdev->dev;  in gpio_fan_probe()
500 	struct device_node *np = dev->of_node;  in gpio_fan_probe()
505 		return -ENOMEM;  in gpio_fan_probe()
507 	fan_data->dev = dev;  in gpio_fan_probe()
513 	mutex_init(&fan_data->lock);  in gpio_fan_probe()
516 	if (fan_data->gpios && fan_data->num_gpios > 0) {  in gpio_fan_probe()
517 		if (!fan_data->speed || fan_data->num_speed <= 1)  in gpio_fan_probe()
518 			return -EINVAL;  in gpio_fan_probe()
528 	fan_data->hwmon_dev =  in gpio_fan_probe()
532 	if (IS_ERR(fan_data->hwmon_dev))  in gpio_fan_probe()
533 		return PTR_ERR(fan_data->hwmon_dev);  in gpio_fan_probe()
536 	if (fan_data->alarm_gpio) {  in gpio_fan_probe()
543 	fan_data->cdev = devm_thermal_of_cooling_device_register(dev, np,  in gpio_fan_probe()
544 				"gpio-fan", fan_data, &gpio_fan_cool_ops);  in gpio_fan_probe()
555 	if (fan_data->gpios)  in gpio_fan_shutdown()
563 	if (fan_data->gpios) {  in gpio_fan_suspend()
564 		fan_data->resume_speed = fan_data->speed_index;  in gpio_fan_suspend()
575 	if (fan_data->gpios)  in gpio_fan_resume()
576 		set_fan_speed(fan_data, fan_data->resume_speed);  in gpio_fan_resume()
587 		.name	= "gpio-fan",
598 MODULE_ALIAS("platform:gpio-fan");