linux/drivers/media/rc/pwm-ir-tx.c
Thomas Gleixner 236b83a3dd treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 122
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 2 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190523091651.414247666@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:39:03 +02:00

131 lines
2.7 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2017 Sean Young <sean@mess.org>
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pwm.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <media/rc-core.h>
#define DRIVER_NAME "pwm-ir-tx"
#define DEVICE_NAME "PWM IR Transmitter"
struct pwm_ir {
struct pwm_device *pwm;
unsigned int carrier;
unsigned int duty_cycle;
};
static const struct of_device_id pwm_ir_of_match[] = {
{ .compatible = "pwm-ir-tx", },
{ },
};
MODULE_DEVICE_TABLE(of, pwm_ir_of_match);
static int pwm_ir_set_duty_cycle(struct rc_dev *dev, u32 duty_cycle)
{
struct pwm_ir *pwm_ir = dev->priv;
pwm_ir->duty_cycle = duty_cycle;
return 0;
}
static int pwm_ir_set_carrier(struct rc_dev *dev, u32 carrier)
{
struct pwm_ir *pwm_ir = dev->priv;
if (!carrier)
return -EINVAL;
pwm_ir->carrier = carrier;
return 0;
}
static int pwm_ir_tx(struct rc_dev *dev, unsigned int *txbuf,
unsigned int count)
{
struct pwm_ir *pwm_ir = dev->priv;
struct pwm_device *pwm = pwm_ir->pwm;
int i, duty, period;
ktime_t edge;
long delta;
period = DIV_ROUND_CLOSEST(NSEC_PER_SEC, pwm_ir->carrier);
duty = DIV_ROUND_CLOSEST(pwm_ir->duty_cycle * period, 100);
pwm_config(pwm, duty, period);
edge = ktime_get();
for (i = 0; i < count; i++) {
if (i % 2) // space
pwm_disable(pwm);
else
pwm_enable(pwm);
edge = ktime_add_us(edge, txbuf[i]);
delta = ktime_us_delta(edge, ktime_get());
if (delta > 0)
usleep_range(delta, delta + 10);
}
pwm_disable(pwm);
return count;
}
static int pwm_ir_probe(struct platform_device *pdev)
{
struct pwm_ir *pwm_ir;
struct rc_dev *rcdev;
int rc;
pwm_ir = devm_kmalloc(&pdev->dev, sizeof(*pwm_ir), GFP_KERNEL);
if (!pwm_ir)
return -ENOMEM;
pwm_ir->pwm = devm_pwm_get(&pdev->dev, NULL);
if (IS_ERR(pwm_ir->pwm))
return PTR_ERR(pwm_ir->pwm);
pwm_ir->carrier = 38000;
pwm_ir->duty_cycle = 50;
rcdev = devm_rc_allocate_device(&pdev->dev, RC_DRIVER_IR_RAW_TX);
if (!rcdev)
return -ENOMEM;
rcdev->priv = pwm_ir;
rcdev->driver_name = DRIVER_NAME;
rcdev->device_name = DEVICE_NAME;
rcdev->tx_ir = pwm_ir_tx;
rcdev->s_tx_duty_cycle = pwm_ir_set_duty_cycle;
rcdev->s_tx_carrier = pwm_ir_set_carrier;
rc = devm_rc_register_device(&pdev->dev, rcdev);
if (rc < 0)
dev_err(&pdev->dev, "failed to register rc device\n");
return rc;
}
static struct platform_driver pwm_ir_driver = {
.probe = pwm_ir_probe,
.driver = {
.name = DRIVER_NAME,
.of_match_table = of_match_ptr(pwm_ir_of_match),
},
};
module_platform_driver(pwm_ir_driver);
MODULE_DESCRIPTION("PWM IR Transmitter");
MODULE_AUTHOR("Sean Young <sean@mess.org>");
MODULE_LICENSE("GPL");