[PATCH 3/4] [media] rc: gpio-ir-tx: add new driver

[PATCH 3/4] [media] rc: gpio-ir-tx: add new driver

[Sean Young]

This is a simple bit-banging GPIO IR TX driver.

Signed-off-by: Sean Young <sean@mess.org>
---
 .../devicetree/bindings/leds/irled/gpio-ir-tx.txt  |  11 ++
 drivers/media/rc/Kconfig                           |  11 ++
 drivers/media/rc/Makefile                          |   1 +
 drivers/media/rc/gpio-ir-tx.c                      | 189 +++++++++++++++++++++
 4 files changed, 212 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/leds/irled/gpio-ir-tx.txt
 create mode 100644 drivers/media/rc/gpio-ir-tx.c

diff --git a/Documentation/devicetree/bindings/leds/irled/gpio-ir-tx.txt b/Documentation/devicetree/bindings/leds/irled/gpio-ir-tx.txt
new file mode 100644
index 0000000..bf4d4fb
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/irled/gpio-ir-tx.txt
@@ -0,0 +1,11 @@
+Device tree bindings for IR LED connected through gpio pin which is used as
+IR transmitter.
+
+Required properties:
+	- compatible: should be "gpio-ir-tx".
+
+Example:
+	irled@0 {
+		compatible = "gpio-ir-tx";
+		gpios = <&gpio1 2 GPIO_ACTIVE_HIGH>;
+	};
diff --git a/drivers/media/rc/Kconfig b/drivers/media/rc/Kconfig
index 5e83b76..ad54011 100644
--- a/drivers/media/rc/Kconfig
+++ b/drivers/media/rc/Kconfig
@@ -388,6 +388,17 @@ config IR_GPIO_CIR
 	   To compile this driver as a module, choose M here: the module will
 	   be called gpio-ir-recv.
 
+config IR_GPIO_TX
+	tristate "GPIO IR bit banging transmitter"
+	depends on RC_CORE
+	depends on LIRC
+	---help---
+	   Say Y if you want to a GPIO based IR transmitter. This is a
+	   bit banging driver.
+
+	   To compile this driver as a module, choose M here: the module will
+	   be called gpio-ir-tx.
+
 config RC_ST
 	tristate "ST remote control receiver"
 	depends on RC_CORE
diff --git a/drivers/media/rc/Makefile b/drivers/media/rc/Makefile
index 245e2c2..3e64a4e 100644
--- a/drivers/media/rc/Makefile
+++ b/drivers/media/rc/Makefile
@@ -32,6 +32,7 @@ obj-$(CONFIG_IR_STREAMZAP) += streamzap.o
 obj-$(CONFIG_IR_WINBOND_CIR) += winbond-cir.o
 obj-$(CONFIG_RC_LOOPBACK) += rc-loopback.o
 obj-$(CONFIG_IR_GPIO_CIR) += gpio-ir-recv.o
+obj-$(CONFIG_IR_GPIO_TX) += gpio-ir-tx.o
 obj-$(CONFIG_IR_IGORPLUGUSB) += igorplugusb.o
 obj-$(CONFIG_IR_IGUANA) += iguanair.o
 obj-$(CONFIG_IR_TTUSBIR) += ttusbir.o
diff --git a/drivers/media/rc/gpio-ir-tx.c b/drivers/media/rc/gpio-ir-tx.c
new file mode 100644
index 0000000..c2ea002
--- /dev/null
+++ b/drivers/media/rc/gpio-ir-tx.c
@@ -0,0 +1,189 @@
+/*
+ * Copyright (C) 2017 Sean Young <sean@mess.org>
+ *
+ * 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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/gpio.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/platform_device.h>
+#include <media/rc-core.h>
+
+#define DRIVER_NAME	"gpio-ir-tx"
+#define DEVICE_NAME	"GPIO IR Bit Banging Transmitter"
+
+struct gpio_rc_dev {
+	int gpio_nr;
+	unsigned int carrier;
+	unsigned int duty_cycle;
+	bool active_low;
+	/* we need a spinlock to hold the cpu while transmitting */
+	spinlock_t lock;
+};
+
+static const struct of_device_id gpio_ir_tx_of_match[] = {
+	{ .compatible = "gpio-ir-tx", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, gpio_ir_tx_of_match);
+
+static int gpio_ir_tx_set_duty_cycle(struct rc_dev *dev, u32 duty_cycle)
+{
+	struct gpio_rc_dev *gpio_dev = dev->priv;
+
+	gpio_dev->duty_cycle = duty_cycle;
+
+	return 0;
+}
+
+static int gpio_ir_tx_set_carrier(struct rc_dev *dev, u32 carrier)
+{
+	struct gpio_rc_dev *gpio_dev = dev->priv;
+
+	if (!carrier)
+		return -EINVAL;
+
+	gpio_dev->carrier = carrier;
+
+	return 0;
+}
+
+static int gpio_ir_tx(struct rc_dev *dev, unsigned int *txbuf,
+		      unsigned int count)
+{
+	struct gpio_rc_dev *gpio_dev = dev->priv;
+	unsigned long flags;
+	ktime_t edge;
+	s64 delta;
+	int i;
+	unsigned int pulse, space;
+
+	/* Ensure the dividend fits into 32 bit */
+	pulse = DIV_ROUND_CLOSEST(gpio_dev->duty_cycle * (NSEC_PER_SEC / 100),
+				  gpio_dev->carrier);
+	space = DIV_ROUND_CLOSEST((100l - gpio_dev->duty_cycle) *
+				  (NSEC_PER_SEC / 100), gpio_dev->carrier);
+
+	spin_lock_irqsave(&gpio_dev->lock, flags);
+
+	edge = ktime_get();
+
+	for (i = 0; i < count; i++) {
+		if (i % 2) {
+			// space
+			edge = ktime_add_us(edge, txbuf[i]);
+			delta = ktime_us_delta(edge, ktime_get());
+			if (delta > 10) {
+				spin_unlock_irqrestore(&gpio_dev->lock, flags);
+				usleep_range(delta - 10, delta + 10);
+				spin_lock_irqsave(&gpio_dev->lock, flags);
+			} else if (delta > 0) {
+				udelay(delta);
+			}
+		} else {
+			// pulse
+			ktime_t last = ktime_add_us(edge, txbuf[i]);
+
+			while (ktime_get() < last) {
+				gpio_set_value(gpio_dev->gpio_nr,
+					       gpio_dev->active_low);
+				edge += pulse;
+				delta = ktime_sub(edge, ktime_get());
+				if (delta > 0)
+					ndelay(delta);
+				gpio_set_value(gpio_dev->gpio_nr,
+					       !gpio_dev->active_low);
+				edge += space;
+				delta = ktime_sub(edge, ktime_get());
+				if (delta > 0)
+					ndelay(delta);
+			}
+
+			edge = last;
+		}
+	}
+
+	spin_unlock_irqrestore(&gpio_dev->lock, flags);
+
+	return count;
+}
+
+static int gpio_ir_tx_probe(struct platform_device *pdev)
+{
+	struct gpio_rc_dev *gpio_dev;
+	struct rc_dev *rcdev;
+	enum of_gpio_flags flags;
+	int rc, gpio;
+
+	gpio = of_get_gpio_flags(pdev->dev.of_node, 0, &flags);
+	if (gpio < 0) {
+		if (gpio != -EPROBE_DEFER)
+			dev_err(&pdev->dev, "Failed to get gpio flags (%d)\n",
+				gpio);
+		return -EINVAL;
+	}
+
+	gpio_dev = devm_kzalloc(&pdev->dev, sizeof(*gpio_dev), GFP_KERNEL);
+	if (!gpio_dev)
+		return -ENOMEM;
+
+	rcdev = devm_rc_allocate_device(&pdev->dev, RC_DRIVER_IR_RAW_TX);
+	if (!rcdev)
+		return -ENOMEM;
+
+	rcdev->priv = gpio_dev;
+	rcdev->driver_name = DRIVER_NAME;
+	rcdev->device_name = DEVICE_NAME;
+	rcdev->tx_ir = gpio_ir_tx;
+	rcdev->s_tx_duty_cycle = gpio_ir_tx_set_duty_cycle;
+	rcdev->s_tx_carrier = gpio_ir_tx_set_carrier;
+
+	gpio_dev->gpio_nr = gpio;
+	gpio_dev->active_low = (flags & OF_GPIO_ACTIVE_LOW) != 0;
+	spin_lock_init(&gpio_dev->lock);
+	gpio_dev->carrier = 38000;
+	gpio_dev->duty_cycle = 50;
+
+	rc = devm_gpio_request(&pdev->dev, gpio, "gpio-ir-tx");
+	if (rc < 0)
+		return rc;
+
+	rc = gpio_direction_output(gpio, !gpio_dev->active_low);
+	if (rc < 0)
+		return rc;
+
+	rc = devm_rc_register_device(&pdev->dev, rcdev);
+	if (rc < 0) {
+		dev_err(&pdev->dev, "failed to register rc device\n");
+		return rc;
+	}
+
+	platform_set_drvdata(pdev, gpio_dev);
+
+	return 0;
+}
+
+static struct platform_driver gpio_ir_tx_driver = {
+	.probe	= gpio_ir_tx_probe,
+	.driver = {
+		.name	= DRIVER_NAME,
+		.of_match_table = of_match_ptr(gpio_ir_tx_of_match),
+	},
+};
+module_platform_driver(gpio_ir_tx_driver);
+
+MODULE_DESCRIPTION("GPIO IR Bit Banging Transmitter");
+MODULE_AUTHOR("Sean Young <sean@mess.org>");
+MODULE_LICENSE("GPL");
-- 
2.9.4

Re: [PATCH 3/4] [media] rc: gpio-ir-tx: add new driver

[Rob Herring]

On Sun, Jul 02, 2017 at 12:06:11PM +0100, Sean Young wrote:
> This is a simple bit-banging GPIO IR TX driver.
> 
> Signed-off-by: Sean Young <sean@mess.org>
> ---
>  .../devicetree/bindings/leds/irled/gpio-ir-tx.txt  |  11 ++

Please make this a separate patch.

>  drivers/media/rc/Kconfig                           |  11 ++
>  drivers/media/rc/Makefile                          |   1 +
>  drivers/media/rc/gpio-ir-tx.c                      | 189 +++++++++++++++++++++
>  4 files changed, 212 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/leds/irled/gpio-ir-tx.txt
>  create mode 100644 drivers/media/rc/gpio-ir-tx.c
> 
> diff --git a/Documentation/devicetree/bindings/leds/irled/gpio-ir-tx.txt b/Documentation/devicetree/bindings/leds/irled/gpio-ir-tx.txt
> new file mode 100644
> index 0000000..bf4d4fb
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/leds/irled/gpio-ir-tx.txt
> @@ -0,0 +1,11 @@
> +Device tree bindings for IR LED connected through gpio pin which is used as
> +IR transmitter.
> +
> +Required properties:
> +	- compatible: should be "gpio-ir-tx".

gpios property?

> +
> +Example:
> +	irled@0 {
> +		compatible = "gpio-ir-tx";
> +		gpios = <&gpio1 2 GPIO_ACTIVE_HIGH>;
> +	};

[PATCH 4/4] [media] rc: pwm-ir-tx: add new driver

[Sean Young]

This is new driver which uses pwm, so it is more power-efficient
than the bit banging gpio-ir-tx driver.

Signed-off-by: Sean Young <sean@mess.org>
---
 .../devicetree/bindings/leds/irled/pwm-ir-tx.txt   |  13 ++
 drivers/media/rc/Kconfig                           |  12 ++
 drivers/media/rc/Makefile                          |   1 +
 drivers/media/rc/pwm-ir-tx.c                       | 165 +++++++++++++++++++++
 4 files changed, 191 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/leds/irled/pwm-ir-tx.txt
 create mode 100644 drivers/media/rc/pwm-ir-tx.c

diff --git a/Documentation/devicetree/bindings/leds/irled/pwm-ir-tx.txt b/Documentation/devicetree/bindings/leds/irled/pwm-ir-tx.txt
new file mode 100644
index 0000000..6887a71
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/irled/pwm-ir-tx.txt
@@ -0,0 +1,13 @@
+Device tree bindings for IR LED connected through pwm pin which is used as
+IR transmitter.
+
+Required properties:
+- compatible: should be "pwm-ir-tx".
+- pwms : PWM property to point to the PWM device (phandle)/port (id) and to
+  specify the period time to be used: <&phandle id period_ns>;
+
+Example:
+	irled {
+		compatible = "pwm-ir-tx";
+		pwms = <&pwm0 0 10000000>;
+	};
diff --git a/drivers/media/rc/Kconfig b/drivers/media/rc/Kconfig
index ad54011..c5338e3 100644
--- a/drivers/media/rc/Kconfig
+++ b/drivers/media/rc/Kconfig
@@ -399,6 +399,18 @@ config IR_GPIO_TX
 	   To compile this driver as a module, choose M here: the module will
 	   be called gpio-ir-tx.
 
+config IR_PWM_TX
+	tristate "PWM IR transmitter"
+	depends on RC_CORE
+	depends on LIRC
+	depends on PWM
+	---help---
+	   Say Y if you want to use a PWM based IR transmitter. This is
+	   more power efficient than the bit banging gpio driver.
+
+	   To compile this driver as a module, choose M here: the module will
+	   be called pwm-ir-tx.
+
 config RC_ST
 	tristate "ST remote control receiver"
 	depends on RC_CORE
diff --git a/drivers/media/rc/Makefile b/drivers/media/rc/Makefile
index 3e64a4e..466c402 100644
--- a/drivers/media/rc/Makefile
+++ b/drivers/media/rc/Makefile
@@ -33,6 +33,7 @@ obj-$(CONFIG_IR_WINBOND_CIR) += winbond-cir.o
 obj-$(CONFIG_RC_LOOPBACK) += rc-loopback.o
 obj-$(CONFIG_IR_GPIO_CIR) += gpio-ir-recv.o
 obj-$(CONFIG_IR_GPIO_TX) += gpio-ir-tx.o
+obj-$(CONFIG_IR_PWM_TX) += pwm-ir-tx.o
 obj-$(CONFIG_IR_IGORPLUGUSB) += igorplugusb.o
 obj-$(CONFIG_IR_IGUANA) += iguanair.o
 obj-$(CONFIG_IR_TTUSBIR) += ttusbir.o
diff --git a/drivers/media/rc/pwm-ir-tx.c b/drivers/media/rc/pwm-ir-tx.c
new file mode 100644
index 0000000..1ab10b4
--- /dev/null
+++ b/drivers/media/rc/pwm-ir-tx.c
@@ -0,0 +1,165 @@
+/*
+ * Copyright (C) 2017 Sean Young <sean@mess.org>
+ *
+ * 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.
+ */
+
+#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;
+	/* One transmission at a time */
+	struct mutex lock;
+};
+
+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;
+	s64 delta;
+
+	if (mutex_lock_interruptible(&pwm_ir->lock))
+		return -ERESTARTSYS;
+
+	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);
+
+	mutex_unlock(&pwm_ir->lock);
+
+	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_kzalloc(&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;
+	mutex_init(&pwm_ir->lock);
+
+	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;
+	}
+
+	platform_set_drvdata(pdev, pwm_ir);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int pwm_ir_suspend(struct platform_device *dev, pm_message_t state)
+{
+	struct pwm_ir *pwm_ir = platform_get_drvdata(dev);
+
+	if (mutex_is_locked(&pwm_ir->lock))
+		return -EAGAIN;
+
+	return 0;
+}
+#else
+#define pwm_ir_suspend NULL
+#endif
+
+static struct platform_driver pwm_ir_driver = {
+	.probe = pwm_ir_probe,
+	.suspend = pwm_ir_suspend,
+	.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");
-- 
2.9.4

Re: [PATCH 4/4] [media] rc: pwm-ir-tx: add new driver

[Sean Young]

On Sun, Jul 02, 2017 at 12:06:13PM +0100, Sean Young wrote:
> This is new driver which uses pwm, so it is more power-efficient
> than the bit banging gpio-ir-tx driver.
> 
> Signed-off-by: Sean Young <sean-hENCXIMQXOg@public.gmane.org>
> ---
>  .../devicetree/bindings/leds/irled/pwm-ir-tx.txt   |  13 ++
>  drivers/media/rc/Kconfig                           |  12 ++
>  drivers/media/rc/Makefile                          |   1 +
>  drivers/media/rc/pwm-ir-tx.c                       | 165 +++++++++++++++++++++
>  4 files changed, 191 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/leds/irled/pwm-ir-tx.txt
>  create mode 100644 drivers/media/rc/pwm-ir-tx.c
> 
> diff --git a/Documentation/devicetree/bindings/leds/irled/pwm-ir-tx.txt b/Documentation/devicetree/bindings/leds/irled/pwm-ir-tx.txt
> new file mode 100644
> index 0000000..6887a71
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/leds/irled/pwm-ir-tx.txt
> @@ -0,0 +1,13 @@
> +Device tree bindings for IR LED connected through pwm pin which is used as
> +IR transmitter.
> +
> +Required properties:
> +- compatible: should be "pwm-ir-tx".
> +- pwms : PWM property to point to the PWM device (phandle)/port (id) and to
> +  specify the period time to be used: <&phandle id period_ns>;
> +
> +Example:
> +	irled {
> +		compatible = "pwm-ir-tx";
> +		pwms = <&pwm0 0 10000000>;
> +	};
> diff --git a/drivers/media/rc/Kconfig b/drivers/media/rc/Kconfig
> index ad54011..c5338e3 100644
> --- a/drivers/media/rc/Kconfig
> +++ b/drivers/media/rc/Kconfig
> @@ -399,6 +399,18 @@ config IR_GPIO_TX
>  	   To compile this driver as a module, choose M here: the module will
>  	   be called gpio-ir-tx.
>  
> +config IR_PWM_TX
> +	tristate "PWM IR transmitter"
> +	depends on RC_CORE
> +	depends on LIRC
> +	depends on PWM
> +	---help---
> +	   Say Y if you want to use a PWM based IR transmitter. This is
> +	   more power efficient than the bit banging gpio driver.
> +
> +	   To compile this driver as a module, choose M here: the module will
> +	   be called pwm-ir-tx.
> +
>  config RC_ST
>  	tristate "ST remote control receiver"
>  	depends on RC_CORE
> diff --git a/drivers/media/rc/Makefile b/drivers/media/rc/Makefile
> index 3e64a4e..466c402 100644
> --- a/drivers/media/rc/Makefile
> +++ b/drivers/media/rc/Makefile
> @@ -33,6 +33,7 @@ obj-$(CONFIG_IR_WINBOND_CIR) += winbond-cir.o
>  obj-$(CONFIG_RC_LOOPBACK) += rc-loopback.o
>  obj-$(CONFIG_IR_GPIO_CIR) += gpio-ir-recv.o
>  obj-$(CONFIG_IR_GPIO_TX) += gpio-ir-tx.o
> +obj-$(CONFIG_IR_PWM_TX) += pwm-ir-tx.o
>  obj-$(CONFIG_IR_IGORPLUGUSB) += igorplugusb.o
>  obj-$(CONFIG_IR_IGUANA) += iguanair.o
>  obj-$(CONFIG_IR_TTUSBIR) += ttusbir.o
> diff --git a/drivers/media/rc/pwm-ir-tx.c b/drivers/media/rc/pwm-ir-tx.c
> new file mode 100644
> index 0000000..1ab10b4
> --- /dev/null
> +++ b/drivers/media/rc/pwm-ir-tx.c
> @@ -0,0 +1,165 @@
> +/*
> + * Copyright (C) 2017 Sean Young <sean-hENCXIMQXOg@public.gmane.org>
> + *
> + * 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.
> + */
> +
> +#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;
> +	/* One transmission at a time */
> +	struct mutex lock;
> +};
> +
> +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;
> +	s64 delta;
> +
> +	if (mutex_lock_interruptible(&pwm_ir->lock))
> +		return -ERESTARTSYS;
> +
> +	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);
> +
> +	mutex_unlock(&pwm_ir->lock);
> +
> +	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_kzalloc(&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;
> +	mutex_init(&pwm_ir->lock);
> +
> +	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;
> +	}
> +
> +	platform_set_drvdata(pdev, pwm_ir);
> +
> +	return 0;
> +}
> +
> +#ifdef CONFIG_PM
> +static int pwm_ir_suspend(struct platform_device *dev, pm_message_t state)
> +{
> +	struct pwm_ir *pwm_ir = platform_get_drvdata(dev);
> +
> +	if (mutex_is_locked(&pwm_ir->lock))
> +		return -EAGAIN;
> +
> +	return 0;
> +}

So this suspend function exists so that suspend does not happen while we're
transmitting; but all processing are frozen before the suspend gets called,
so we're too late in that case.

Besiders, during transmission in pwm_ir_tx() we're never in interruptable
sleep so this problem should not exist anyway.

Sean

> +#else
> +#define pwm_ir_suspend NULL
> +#endif
> +
> +static struct platform_driver pwm_ir_driver = {
> +	.probe = pwm_ir_probe,
> +	.suspend = pwm_ir_suspend,
> +	.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-hENCXIMQXOg@public.gmane.org>");
> +MODULE_LICENSE("GPL");
> -- 
> 2.9.4
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Re: [PATCH 4/4] [media] rc: pwm-ir-tx: add new driver

[Rob Herring]

On Sun, Jul 02, 2017 at 12:06:13PM +0100, Sean Young wrote:
> This is new driver which uses pwm, so it is more power-efficient
> than the bit banging gpio-ir-tx driver.
> 
> Signed-off-by: Sean Young <sean-hENCXIMQXOg@public.gmane.org>
> ---
>  .../devicetree/bindings/leds/irled/pwm-ir-tx.txt   |  13 ++

Please make this a separate patch.

>  drivers/media/rc/Kconfig                           |  12 ++
>  drivers/media/rc/Makefile                          |   1 +
>  drivers/media/rc/pwm-ir-tx.c                       | 165 +++++++++++++++++++++
>  4 files changed, 191 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/leds/irled/pwm-ir-tx.txt
>  create mode 100644 drivers/media/rc/pwm-ir-tx.c
> 
> diff --git a/Documentation/devicetree/bindings/leds/irled/pwm-ir-tx.txt b/Documentation/devicetree/bindings/leds/irled/pwm-ir-tx.txt
> new file mode 100644
> index 0000000..6887a71
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/leds/irled/pwm-ir-tx.txt
> @@ -0,0 +1,13 @@
> +Device tree bindings for IR LED connected through pwm pin which is used as
> +IR transmitter.
> +
> +Required properties:
> +- compatible: should be "pwm-ir-tx".
> +- pwms : PWM property to point to the PWM device (phandle)/port (id) and to
> +  specify the period time to be used: <&phandle id period_ns>;
> +
> +Example:
> +	irled {
> +		compatible = "pwm-ir-tx";
> +		pwms = <&pwm0 0 10000000>;
> +	};
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Re: [PATCH 4/4] [media] rc: pwm-ir-tx: add new driver

[Pavel Machek]

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On Fri 2017-07-07 08:59:28, Rob Herring wrote:
> On Sun, Jul 02, 2017 at 12:06:13PM +0100, Sean Young wrote:
> > This is new driver which uses pwm, so it is more power-efficient
> > than the bit banging gpio-ir-tx driver.
> > 
> > Signed-off-by: Sean Young <sean@mess.org>
> > ---
> >  .../devicetree/bindings/leds/irled/pwm-ir-tx.txt   |  13 ++
> 
> Please make this a separate patch.

Come on... The driver is trivial, and you even quoted the binding
below. Saying "Acked-by:" would not have been that much additional
work...

Thanks,
								Pavel


> >  drivers/media/rc/Kconfig                           |  12 ++
> >  drivers/media/rc/Makefile                          |   1 +
> >  drivers/media/rc/pwm-ir-tx.c                       | 165 +++++++++++++++++++++
> >  4 files changed, 191 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/leds/irled/pwm-ir-tx.txt
> >  create mode 100644 drivers/media/rc/pwm-ir-tx.c
> > 
> > diff --git a/Documentation/devicetree/bindings/leds/irled/pwm-ir-tx.txt b/Documentation/devicetree/bindings/leds/irled/pwm-ir-tx.txt
> > new file mode 100644
> > index 0000000..6887a71
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/leds/irled/pwm-ir-tx.txt
> > @@ -0,0 +1,13 @@
> > +Device tree bindings for IR LED connected through pwm pin which is used as
> > +IR transmitter.
> > +
> > +Required properties:
> > +- compatible: should be "pwm-ir-tx".
> > +- pwms : PWM property to point to the PWM device (phandle)/port (id) and to
> > +  specify the period time to be used: <&phandle id period_ns>;
> > +
> > +Example:
> > +	irled {
> > +		compatible = "pwm-ir-tx";
> > +		pwms = <&pwm0 0 10000000>;
> > +	};

-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: [PATCH 4/4] [media] rc: pwm-ir-tx: add new driver

[Rob Herring]

On Fri, Jul 7, 2017 at 11:15 AM, Pavel Machek <pavel@ucw.cz> wrote:
> On Fri 2017-07-07 08:59:28, Rob Herring wrote:
>> On Sun, Jul 02, 2017 at 12:06:13PM +0100, Sean Young wrote:
>> > This is new driver which uses pwm, so it is more power-efficient
>> > than the bit banging gpio-ir-tx driver.
>> >
>> > Signed-off-by: Sean Young <sean@mess.org>
>> > ---
>> >  .../devicetree/bindings/leds/irled/pwm-ir-tx.txt   |  13 ++
>>
>> Please make this a separate patch.
>
> Come on... The driver is trivial, and you even quoted the binding
> below. Saying "Acked-by:" would not have been that much additional
> work...

True, and I don't always ask for it especially when there is no other
comment. However, the gpio-ir-tx patch needs other changes anyway.

Rob