1 files changed, 285 insertions, 0 deletions
diff --git a/drivers/media/rc/ir-rx51.c b/drivers/media/rc/ir-rx51.c
new file mode 100644
index 0000000000..13e81bf800
--- /dev/null
+++ b/drivers/media/rc/ir-rx51.c
@@ -0,0 +1,285 @@
+// 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");