+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * Copyright (C) 2008 Nokia Corporation
- *
- * Based on lirc_serial.c
- */
-#include <linux/clk.h>
-#include <linux/module.h>
-#include <linux/platform_device.h>
-#include <linux/wait.h>
-#include <linux/pwm.h>
-#include <linux/of.h>
-#include <linux/hrtimer.h>
-
-#include <media/rc-core.h>
-
-#define WBUF_LEN 256
-
-struct ir_rx51 {
- struct rc_dev *rcdev;
- struct pwm_device *pwm;
- struct pwm_state state;
- struct hrtimer timer;
- struct device *dev;
- wait_queue_head_t wqueue;
-
- unsigned int freq; /* carrier frequency */
- unsigned int duty_cycle; /* carrier duty cycle */
- int wbuf[WBUF_LEN];
- int wbuf_index;
- unsigned long device_is_open;
-};
-
-static inline void ir_rx51_on(struct ir_rx51 *ir_rx51)
-{
- ir_rx51->state.enabled = true;
- pwm_apply_state(ir_rx51->pwm, &ir_rx51->state);
-}
-
-static inline void ir_rx51_off(struct ir_rx51 *ir_rx51)
-{
- ir_rx51->state.enabled = false;
- pwm_apply_state(ir_rx51->pwm, &ir_rx51->state);
-}
-
-static int init_timing_params(struct ir_rx51 *ir_rx51)
-{
- ir_rx51->state.period = DIV_ROUND_CLOSEST(NSEC_PER_SEC, ir_rx51->freq);
- pwm_set_relative_duty_cycle(&ir_rx51->state, ir_rx51->duty_cycle, 100);
-
- return 0;
-}
-
-static enum hrtimer_restart ir_rx51_timer_cb(struct hrtimer *timer)
-{
- struct ir_rx51 *ir_rx51 = container_of(timer, struct ir_rx51, timer);
- ktime_t now;
-
- if (ir_rx51->wbuf_index < 0) {
- dev_err_ratelimited(ir_rx51->dev,
- "BUG wbuf_index has value of %i\n",
- ir_rx51->wbuf_index);
- goto end;
- }
-
- /*
- * If we happen to hit an odd latency spike, loop through the
- * pulses until we catch up.
- */
- do {
- u64 ns;
-
- if (ir_rx51->wbuf_index >= WBUF_LEN)
- goto end;
- if (ir_rx51->wbuf[ir_rx51->wbuf_index] == -1)
- goto end;
-
- if (ir_rx51->wbuf_index % 2)
- ir_rx51_off(ir_rx51);
- else
- ir_rx51_on(ir_rx51);
-
- ns = US_TO_NS(ir_rx51->wbuf[ir_rx51->wbuf_index]);
- hrtimer_add_expires_ns(timer, ns);
-
- ir_rx51->wbuf_index++;
-
- now = timer->base->get_time();
-
- } while (hrtimer_get_expires_tv64(timer) < now);
-
- return HRTIMER_RESTART;
-end:
- /* Stop TX here */
- ir_rx51_off(ir_rx51);
- ir_rx51->wbuf_index = -1;
-
- wake_up_interruptible(&ir_rx51->wqueue);
-
- return HRTIMER_NORESTART;
-}
-
-static int ir_rx51_tx(struct rc_dev *dev, unsigned int *buffer,
- unsigned int count)
-{
- struct ir_rx51 *ir_rx51 = dev->priv;
-
- if (count > WBUF_LEN)
- return -EINVAL;
-
- memcpy(ir_rx51->wbuf, buffer, count * sizeof(unsigned int));
-
- /* Wait any pending transfers to finish */
- wait_event_interruptible(ir_rx51->wqueue, ir_rx51->wbuf_index < 0);
-
- init_timing_params(ir_rx51);
- if (count < WBUF_LEN)
- ir_rx51->wbuf[count] = -1; /* Insert termination mark */
-
- /*
- * REVISIT: Adjust latency requirements so the device doesn't go in too
- * deep sleep states with pm_qos_add_request().
- */
-
- ir_rx51_on(ir_rx51);
- ir_rx51->wbuf_index = 1;
- hrtimer_start(&ir_rx51->timer,
- ns_to_ktime(US_TO_NS(ir_rx51->wbuf[0])),
- HRTIMER_MODE_REL);
- /*
- * Don't return back to the userspace until the transfer has
- * finished
- */
- wait_event_interruptible(ir_rx51->wqueue, ir_rx51->wbuf_index < 0);
-
- /* REVISIT: Remove pm_qos constraint, we can sleep again */
-
- return count;
-}
-
-static int ir_rx51_open(struct rc_dev *dev)
-{
- struct ir_rx51 *ir_rx51 = dev->priv;
-
- if (test_and_set_bit(1, &ir_rx51->device_is_open))
- return -EBUSY;
-
- ir_rx51->pwm = pwm_get(ir_rx51->dev, NULL);
- if (IS_ERR(ir_rx51->pwm)) {
- int res = PTR_ERR(ir_rx51->pwm);
-
- dev_err(ir_rx51->dev, "pwm_get failed: %d\n", res);
- return res;
- }
-
- return 0;
-}
-
-static void ir_rx51_release(struct rc_dev *dev)
-{
- struct ir_rx51 *ir_rx51 = dev->priv;
-
- hrtimer_cancel(&ir_rx51->timer);
- ir_rx51_off(ir_rx51);
- pwm_put(ir_rx51->pwm);
-
- clear_bit(1, &ir_rx51->device_is_open);
-}
-
-static struct ir_rx51 ir_rx51 = {
- .duty_cycle = 50,
- .wbuf_index = -1,
-};
-
-static int ir_rx51_set_duty_cycle(struct rc_dev *dev, u32 duty)
-{
- struct ir_rx51 *ir_rx51 = dev->priv;
-
- ir_rx51->duty_cycle = duty;
-
- return 0;
-}
-
-static int ir_rx51_set_tx_carrier(struct rc_dev *dev, u32 carrier)
-{
- struct ir_rx51 *ir_rx51 = dev->priv;
-
- if (carrier > 500000 || carrier < 20000)
- return -EINVAL;
-
- ir_rx51->freq = carrier;
-
- return 0;
-}
-
-#ifdef CONFIG_PM
-
-static int ir_rx51_suspend(struct platform_device *dev, pm_message_t state)
-{
- /*
- * In case the device is still open, do not suspend. Normally
- * this should not be a problem as lircd only keeps the device
- * open only for short periods of time. We also don't want to
- * get involved with race conditions that might happen if we
- * were in a middle of a transmit. Thus, we defer any suspend
- * actions until transmit has completed.
- */
- if (test_and_set_bit(1, &ir_rx51.device_is_open))
- return -EAGAIN;
-
- clear_bit(1, &ir_rx51.device_is_open);
-
- return 0;
-}
-
-static int ir_rx51_resume(struct platform_device *dev)
-{
- return 0;
-}
-
-#else
-
-#define ir_rx51_suspend NULL
-#define ir_rx51_resume NULL
-
-#endif /* CONFIG_PM */
-
-static int ir_rx51_probe(struct platform_device *dev)
-{
- struct pwm_device *pwm;
- struct rc_dev *rcdev;
-
- pwm = pwm_get(&dev->dev, NULL);
- if (IS_ERR(pwm))
- return dev_err_probe(&dev->dev, PTR_ERR(pwm), "pwm_get failed\n");
-
- /* Use default, in case userspace does not set the carrier */
- ir_rx51.freq = DIV_ROUND_CLOSEST_ULL(pwm_get_period(pwm), NSEC_PER_SEC);
- pwm_init_state(pwm, &ir_rx51.state);
- pwm_put(pwm);
-
- hrtimer_init(&ir_rx51.timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
- ir_rx51.timer.function = ir_rx51_timer_cb;
-
- ir_rx51.dev = &dev->dev;
-
- rcdev = devm_rc_allocate_device(&dev->dev, RC_DRIVER_IR_RAW_TX);
- if (!rcdev)
- return -ENOMEM;
-
- rcdev->priv = &ir_rx51;
- rcdev->open = ir_rx51_open;
- rcdev->close = ir_rx51_release;
- rcdev->tx_ir = ir_rx51_tx;
- rcdev->s_tx_duty_cycle = ir_rx51_set_duty_cycle;
- rcdev->s_tx_carrier = ir_rx51_set_tx_carrier;
- rcdev->driver_name = KBUILD_MODNAME;
-
- ir_rx51.rcdev = rcdev;
-
- return devm_rc_register_device(&dev->dev, ir_rx51.rcdev);
-}
-
-static const struct of_device_id ir_rx51_match[] = {
- {
- .compatible = "nokia,n900-ir",
- },
- {},
-};
-MODULE_DEVICE_TABLE(of, ir_rx51_match);
-
-static struct platform_driver ir_rx51_platform_driver = {
- .probe = ir_rx51_probe,
- .suspend = ir_rx51_suspend,
- .resume = ir_rx51_resume,
- .driver = {
- .name = KBUILD_MODNAME,
- .of_match_table = ir_rx51_match,
- },
-};
-module_platform_driver(ir_rx51_platform_driver);
-
-MODULE_DESCRIPTION("IR TX driver for Nokia RX51");
-MODULE_AUTHOR("Nokia Corporation");
-MODULE_LICENSE("GPL");