1 // SPDX-License-Identifier: GPL-2.0-or-later
3  *  Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
4  *  PWM beeper driver
14 #include <linux/pwm.h>
20 	struct pwm_device *pwm;  member
31 static int pwm_beeper_on(struct pwm_beeper *beeper, unsigned long period)  in pwm_beeper_on()  argument
36 	pwm_get_state(beeper->pwm, &state);  in pwm_beeper_on()
42 	error = pwm_apply_state(beeper->pwm, &state);  in pwm_beeper_on()
46 	if (!beeper->amplifier_on) {  in pwm_beeper_on()
47 		error = regulator_enable(beeper->amplifier);  in pwm_beeper_on()
49 			pwm_disable(beeper->pwm);  in pwm_beeper_on()
53 		beeper->amplifier_on = true;  in pwm_beeper_on()
59 static void pwm_beeper_off(struct pwm_beeper *beeper)  in pwm_beeper_off()  argument
61 	if (beeper->amplifier_on) {  in pwm_beeper_off()
62 		regulator_disable(beeper->amplifier);  in pwm_beeper_off()
63 		beeper->amplifier_on = false;  in pwm_beeper_off()
66 	pwm_disable(beeper->pwm);  in pwm_beeper_off()
71 	struct pwm_beeper *beeper = container_of(work, struct pwm_beeper, work);  in pwm_beeper_work()  local
72 	unsigned long period = READ_ONCE(beeper->period);  in pwm_beeper_work()
75 		pwm_beeper_on(beeper, period);  in pwm_beeper_work()
77 		pwm_beeper_off(beeper);  in pwm_beeper_work()
83 	struct pwm_beeper *beeper = input_get_drvdata(input);  in pwm_beeper_event()  local
86 		return -EINVAL;  in pwm_beeper_event()
90 		value = value ? beeper->bell_frequency : 0;  in pwm_beeper_event()
95 		return -EINVAL;  in pwm_beeper_event()
99 		beeper->period = 0;  in pwm_beeper_event()
101 		beeper->period = HZ_TO_NANOSECONDS(value);  in pwm_beeper_event()
103 	if (!beeper->suspended)  in pwm_beeper_event()
104 		schedule_work(&beeper->work);  in pwm_beeper_event()
109 static void pwm_beeper_stop(struct pwm_beeper *beeper)  in pwm_beeper_stop()  argument
111 	cancel_work_sync(&beeper->work);  in pwm_beeper_stop()
112 	pwm_beeper_off(beeper);  in pwm_beeper_stop()
117 	struct pwm_beeper *beeper = input_get_drvdata(input);  in pwm_beeper_close()  local
119 	pwm_beeper_stop(beeper);  in pwm_beeper_close()
124 	struct device *dev = &pdev->dev;  in pwm_beeper_probe()
125 	struct pwm_beeper *beeper;  in pwm_beeper_probe()  local
130 	beeper = devm_kzalloc(dev, sizeof(*beeper), GFP_KERNEL);  in pwm_beeper_probe()
131 	if (!beeper)  in pwm_beeper_probe()
132 		return -ENOMEM;  in pwm_beeper_probe()
134 	beeper->pwm = devm_pwm_get(dev, NULL);  in pwm_beeper_probe()
135 	if (IS_ERR(beeper->pwm)) {  in pwm_beeper_probe()
136 		error = PTR_ERR(beeper->pwm);  in pwm_beeper_probe()
137 		if (error != -EPROBE_DEFER)  in pwm_beeper_probe()
138 			dev_err(dev, "Failed to request PWM device: %d\n",  in pwm_beeper_probe()
143 	/* Sync up PWM state and ensure it is off. */  in pwm_beeper_probe()
144 	pwm_init_state(beeper->pwm, &state);  in pwm_beeper_probe()
146 	error = pwm_apply_state(beeper->pwm, &state);  in pwm_beeper_probe()
148 		dev_err(dev, "failed to apply initial PWM state: %d\n",  in pwm_beeper_probe()
153 	beeper->amplifier = devm_regulator_get(dev, "amp");  in pwm_beeper_probe()
154 	if (IS_ERR(beeper->amplifier)) {  in pwm_beeper_probe()
155 		error = PTR_ERR(beeper->amplifier);  in pwm_beeper_probe()
156 		if (error != -EPROBE_DEFER)  in pwm_beeper_probe()
162 	INIT_WORK(&beeper->work, pwm_beeper_work);  in pwm_beeper_probe()
164 	error = device_property_read_u32(dev, "beeper-hz", &bell_frequency);  in pwm_beeper_probe()
168 			"failed to parse 'beeper-hz' property, using default: %uHz\n",  in pwm_beeper_probe()
172 	beeper->bell_frequency = bell_frequency;  in pwm_beeper_probe()
174 	beeper->input = devm_input_allocate_device(dev);  in pwm_beeper_probe()
175 	if (!beeper->input) {  in pwm_beeper_probe()
177 		return -ENOMEM;  in pwm_beeper_probe()
180 	beeper->input->name = "pwm-beeper";  in pwm_beeper_probe()
181 	beeper->input->phys = "pwm/input0";  in pwm_beeper_probe()
182 	beeper->input->id.bustype = BUS_HOST;  in pwm_beeper_probe()
183 	beeper->input->id.vendor = 0x001f;  in pwm_beeper_probe()
184 	beeper->input->id.product = 0x0001;  in pwm_beeper_probe()
185 	beeper->input->id.version = 0x0100;  in pwm_beeper_probe()
187 	input_set_capability(beeper->input, EV_SND, SND_TONE);  in pwm_beeper_probe()
188 	input_set_capability(beeper->input, EV_SND, SND_BELL);  in pwm_beeper_probe()
190 	beeper->input->event = pwm_beeper_event;  in pwm_beeper_probe()
191 	beeper->input->close = pwm_beeper_close;  in pwm_beeper_probe()
193 	input_set_drvdata(beeper->input, beeper);  in pwm_beeper_probe()
195 	error = input_register_device(beeper->input);  in pwm_beeper_probe()
201 	platform_set_drvdata(pdev, beeper);  in pwm_beeper_probe()
208 	struct pwm_beeper *beeper = dev_get_drvdata(dev);  in pwm_beeper_suspend()  local
212 	 * beeper->suspended, but to ensure that pwm_beeper_event  in pwm_beeper_suspend()
213 	 * does not re-submit work once flag is set.  in pwm_beeper_suspend()
215 	spin_lock_irq(&beeper->input->event_lock);  in pwm_beeper_suspend()
216 	beeper->suspended = true;  in pwm_beeper_suspend()
217 	spin_unlock_irq(&beeper->input->event_lock);  in pwm_beeper_suspend()
219 	pwm_beeper_stop(beeper);  in pwm_beeper_suspend()
226 	struct pwm_beeper *beeper = dev_get_drvdata(dev);  in pwm_beeper_resume()  local
228 	spin_lock_irq(&beeper->input->event_lock);  in pwm_beeper_resume()
229 	beeper->suspended = false;  in pwm_beeper_resume()
230 	spin_unlock_irq(&beeper->input->event_lock);  in pwm_beeper_resume()
233 	schedule_work(&beeper->work);  in pwm_beeper_resume()
243 	{ .compatible = "pwm-beeper", },
252 		.name	= "pwm-beeper",
259 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
260 MODULE_DESCRIPTION("PWM beeper driver");
262 MODULE_ALIAS("platform:pwm-beeper");