1 // SPDX-License-Identifier: GPL-2.0-or-later
8 #include <linux/pwm.h>
15 #include <media/rc-core.h>
17 #define DRIVER_NAME	"pwm-ir-tx"
18 #define DEVICE_NAME	"PWM IR Transmitter"
21 	struct pwm_device *pwm;  member
22 	struct hrtimer timer;  member
33 	{ .compatible = "pwm-ir-tx", },
34 	{ .compatible = "nokia,n900-ir" },
41 	struct pwm_ir *pwm_ir = dev->priv;  in pwm_ir_set_duty_cycle()
43 	pwm_ir->duty_cycle = duty_cycle;  in pwm_ir_set_duty_cycle()
50 	struct pwm_ir *pwm_ir = dev->priv;  in pwm_ir_set_carrier()
53 		return -EINVAL;  in pwm_ir_set_carrier()
55 	pwm_ir->carrier = carrier;  in pwm_ir_set_carrier()
63 	struct pwm_ir *pwm_ir = dev->priv;  in pwm_ir_tx_sleep()
64 	struct pwm_device *pwm = pwm_ir->pwm;  in pwm_ir_tx_sleep()  local
70 	pwm_init_state(pwm, &state);  in pwm_ir_tx_sleep()
72 	state.period = DIV_ROUND_CLOSEST(NSEC_PER_SEC, pwm_ir->carrier);  in pwm_ir_tx_sleep()
73 	pwm_set_relative_duty_cycle(&state, pwm_ir->duty_cycle, 100);  in pwm_ir_tx_sleep()
79 		pwm_apply_might_sleep(pwm, &state);  in pwm_ir_tx_sleep()
88 	pwm_apply_might_sleep(pwm, &state);  in pwm_ir_tx_sleep()
96 	struct pwm_ir *pwm_ir = dev->priv;  in pwm_ir_tx_atomic()
97 	struct pwm_device *pwm = pwm_ir->pwm;  in pwm_ir_tx_atomic()  local
100 	pwm_init_state(pwm, &state);  in pwm_ir_tx_atomic()
102 	state.period = DIV_ROUND_CLOSEST(NSEC_PER_SEC, pwm_ir->carrier);  in pwm_ir_tx_atomic()
103 	pwm_set_relative_duty_cycle(&state, pwm_ir->duty_cycle, 100);  in pwm_ir_tx_atomic()
105 	pwm_ir->txbuf = txbuf;  in pwm_ir_tx_atomic()
106 	pwm_ir->txbuf_len = count;  in pwm_ir_tx_atomic()
107 	pwm_ir->txbuf_index = 0;  in pwm_ir_tx_atomic()
108 	pwm_ir->state = &state;  in pwm_ir_tx_atomic()
110 	hrtimer_start(&pwm_ir->timer, 0, HRTIMER_MODE_REL);  in pwm_ir_tx_atomic()
112 	wait_for_completion(&pwm_ir->tx_done);  in pwm_ir_tx_atomic()
117 static enum hrtimer_restart pwm_ir_timer(struct hrtimer *timer)  in pwm_ir_timer()  argument
119 	struct pwm_ir *pwm_ir = container_of(timer, struct pwm_ir, timer);  in pwm_ir_timer()
129 		pwm_ir->state->enabled = !(pwm_ir->txbuf_index % 2);  in pwm_ir_timer()
130 		pwm_apply_atomic(pwm_ir->pwm, pwm_ir->state);  in pwm_ir_timer()
132 		if (pwm_ir->txbuf_index >= pwm_ir->txbuf_len) {  in pwm_ir_timer()
133 			complete(&pwm_ir->tx_done);  in pwm_ir_timer()
138 		ns = US_TO_NS(pwm_ir->txbuf[pwm_ir->txbuf_index]);  in pwm_ir_timer()
139 		hrtimer_add_expires_ns(timer, ns);  in pwm_ir_timer()
141 		pwm_ir->txbuf_index++;  in pwm_ir_timer()
143 		now = timer->base->get_time();  in pwm_ir_timer()
144 	} while (hrtimer_get_expires_tv64(timer) < now);  in pwm_ir_timer()
155 	pwm_ir = devm_kmalloc(&pdev->dev, sizeof(*pwm_ir), GFP_KERNEL);  in pwm_ir_probe()
157 		return -ENOMEM;  in pwm_ir_probe()
159 	pwm_ir->pwm = devm_pwm_get(&pdev->dev, NULL);  in pwm_ir_probe()
160 	if (IS_ERR(pwm_ir->pwm))  in pwm_ir_probe()
161 		return PTR_ERR(pwm_ir->pwm);  in pwm_ir_probe()
163 	pwm_ir->carrier = 38000;  in pwm_ir_probe()
164 	pwm_ir->duty_cycle = 50;  in pwm_ir_probe()
166 	rcdev = devm_rc_allocate_device(&pdev->dev, RC_DRIVER_IR_RAW_TX);  in pwm_ir_probe()
168 		return -ENOMEM;  in pwm_ir_probe()
170 	if (pwm_might_sleep(pwm_ir->pwm)) {  in pwm_ir_probe()
171 		dev_info(&pdev->dev, "TX will not be accurate as PWM device might sleep\n");  in pwm_ir_probe()
172 		rcdev->tx_ir = pwm_ir_tx_sleep;  in pwm_ir_probe()
174 		init_completion(&pwm_ir->tx_done);  in pwm_ir_probe()
175 		hrtimer_init(&pwm_ir->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);  in pwm_ir_probe()
176 		pwm_ir->timer.function = pwm_ir_timer;  in pwm_ir_probe()
177 		rcdev->tx_ir = pwm_ir_tx_atomic;  in pwm_ir_probe()
180 	rcdev->priv = pwm_ir;  in pwm_ir_probe()
181 	rcdev->driver_name = DRIVER_NAME;  in pwm_ir_probe()
182 	rcdev->device_name = DEVICE_NAME;  in pwm_ir_probe()
183 	rcdev->s_tx_duty_cycle = pwm_ir_set_duty_cycle;  in pwm_ir_probe()
184 	rcdev->s_tx_carrier = pwm_ir_set_carrier;  in pwm_ir_probe()
186 	rc = devm_rc_register_device(&pdev->dev, rcdev);  in pwm_ir_probe()
188 		dev_err(&pdev->dev, "failed to register rc device\n");  in pwm_ir_probe()
202 MODULE_DESCRIPTION("PWM IR Transmitter");