summaryrefslogtreecommitdiffstats
path: root/drivers/media/rc/ir-rx51.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/media/rc/ir-rx51.c')
-rw-r--r--drivers/media/rc/ir-rx51.c305
1 files changed, 305 insertions, 0 deletions
diff --git a/drivers/media/rc/ir-rx51.c b/drivers/media/rc/ir-rx51.c
new file mode 100644
index 000000000..8a93f7468
--- /dev/null
+++ b/drivers/media/rc/ir-rx51.c
@@ -0,0 +1,305 @@
+/*
+ * Copyright (C) 2008 Nokia Corporation
+ *
+ * Based on lirc_serial.c
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+#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 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)
+{
+ pwm_enable(ir_rx51->pwm);
+}
+
+static inline void ir_rx51_off(struct ir_rx51 *ir_rx51)
+{
+ pwm_disable(ir_rx51->pwm);
+}
+
+static int init_timing_params(struct ir_rx51 *ir_rx51)
+{
+ struct pwm_device *pwm = ir_rx51->pwm;
+ int duty, period = DIV_ROUND_CLOSEST(NSEC_PER_SEC, ir_rx51->freq);
+
+ duty = DIV_ROUND_CLOSEST(ir_rx51->duty_cycle * period, 100);
+
+ pwm_config(pwm, duty, period);
+
+ 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)) {
+ int err = PTR_ERR(pwm);
+
+ if (err != -EPROBE_DEFER)
+ dev_err(&dev->dev, "pwm_get failed: %d\n", err);
+ return err;
+ }
+
+ /* Use default, in case userspace does not set the carrier */
+ ir_rx51.freq = DIV_ROUND_CLOSEST(pwm_get_period(pwm), NSEC_PER_SEC);
+ 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 int ir_rx51_remove(struct platform_device *dev)
+{
+ return 0;
+}
+
+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,
+ .remove = ir_rx51_remove,
+ .suspend = ir_rx51_suspend,
+ .resume = ir_rx51_resume,
+ .driver = {
+ .name = KBUILD_MODNAME,
+ .of_match_table = of_match_ptr(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");