diff mbox series

[1/2,v2] backlight: gpio: Convert to use GPIO descriptor

Message ID 20170530114822.24308-1-linus.walleij@linaro.org
State Accepted
Commit de7389003ab77fc63296b2adee4cd9c48dc41d5a
Headers show
Series [1/2,v2] backlight: gpio: Convert to use GPIO descriptor | expand

Commit Message

Linus Walleij May 30, 2017, 11:48 a.m. UTC
This driver is predominantly used by device tree systems, all
of which can deal with modern GPIO descriptors. The legacy
GPIO API is only used by one SH board so make the GPIO
descriptor the default way to deal with it.

As an intended side effect we do not need to look around in
the device tree for the inversion flag since the GPIO
descriptors will intrinsically deal with this.

Acked-by: Daniel Thompson <daniel.thompson@linaro.org>

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

---
ChangeLog v1->v2:
- Assign flags value using the ternary operator.
---
 drivers/video/backlight/gpio_backlight.c | 71 +++++++++++++++++++-------------
 1 file changed, 43 insertions(+), 28 deletions(-)

-- 
2.9.4

Comments

Linus Walleij Aug. 1, 2017, 8:20 a.m. UTC | #1
On Tue, May 30, 2017 at 1:48 PM, Linus Walleij <linus.walleij@linaro.org> wrote:

> This driver is predominantly used by device tree systems, all

> of which can deal with modern GPIO descriptors. The legacy

> GPIO API is only used by one SH board so make the GPIO

> descriptor the default way to deal with it.

>

> As an intended side effect we do not need to look around in

> the device tree for the inversion flag since the GPIO

> descriptors will intrinsically deal with this.

>

> Acked-by: Daniel Thompson <daniel.thompson@linaro.org>

> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

> ---

> ChangeLog v1->v2:

> - Assign flags value using the ternary operator.


This patch seems to have been inadvertedly dropped?

Can it be applied, along with 2/2?

Yours,
Linus Walleij
Laurent Pinchart Aug. 1, 2017, 10:29 a.m. UTC | #2
Hi Linus,

Thank you for the patch.

On Tuesday 01 Aug 2017 10:20:32 Linus Walleij wrote:
> On Tue, May 30, 2017 at 1:48 PM, Linus Walleij <linus.walleij@linaro.org> 

wrote:
> > This driver is predominantly used by device tree systems, all

> > of which can deal with modern GPIO descriptors. The legacy

> > GPIO API is only used by one SH board so make the GPIO

> > descriptor the default way to deal with it.

> > 

> > As an intended side effect we do not need to look around in

> > the device tree for the inversion flag since the GPIO

> > descriptors will intrinsically deal with this.

> > 

> > Acked-by: Daniel Thompson <daniel.thompson@linaro.org>

> > Signed-off-by: Linus Walleij <linus.walleij@linaro.org>


Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>


> > ---

> > ChangeLog v1->v2:

> > - Assign flags value using the ternary operator.

> 

> This patch seems to have been inadvertedly dropped?

> 

> Can it be applied, along with 2/2?

> 

> Yours,

> Linus Walleij


-- 
Regards,

Laurent Pinchart
Lee Jones Aug. 7, 2017, 7:53 a.m. UTC | #3
On Tue, 01 Aug 2017, Linus Walleij wrote:

> On Tue, May 30, 2017 at 1:48 PM, Linus Walleij <linus.walleij@linaro.org> wrote:

> 

> > This driver is predominantly used by device tree systems, all

> > of which can deal with modern GPIO descriptors. The legacy

> > GPIO API is only used by one SH board so make the GPIO

> > descriptor the default way to deal with it.

> >

> > As an intended side effect we do not need to look around in

> > the device tree for the inversion flag since the GPIO

> > descriptors will intrinsically deal with this.

> >

> > Acked-by: Daniel Thompson <daniel.thompson@linaro.org>

> > Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

> > ---

> > ChangeLog v1->v2:

> > - Assign flags value using the ternary operator.

> 

> This patch seems to have been inadvertedly dropped?

> 

> Can it be applied, along with 2/2?


The patch hasn't been dropped.  It just hasn't been picked up yet,
since I have been on vacation.  This is my first day back.

I am conducting a first (quick) pass of my inbox now.  Will hoover up
on my second (thorough) pass later today.

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog
Lee Jones Aug. 7, 2017, 4:12 p.m. UTC | #4
On Tue, 30 May 2017, Linus Walleij wrote:

> This driver is predominantly used by device tree systems, all

> of which can deal with modern GPIO descriptors. The legacy

> GPIO API is only used by one SH board so make the GPIO

> descriptor the default way to deal with it.

> 

> As an intended side effect we do not need to look around in

> the device tree for the inversion flag since the GPIO

> descriptors will intrinsically deal with this.

> 

> Acked-by: Daniel Thompson <daniel.thompson@linaro.org>

> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

> ---

> ChangeLog v1->v2:

> - Assign flags value using the ternary operator.

> ---

>  drivers/video/backlight/gpio_backlight.c | 71 +++++++++++++++++++-------------

>  1 file changed, 43 insertions(+), 28 deletions(-)


Applied, thanks.

> diff --git a/drivers/video/backlight/gpio_backlight.c b/drivers/video/backlight/gpio_backlight.c

> index 18134416b154..5ffaff1e4142 100644

> --- a/drivers/video/backlight/gpio_backlight.c

> +++ b/drivers/video/backlight/gpio_backlight.c

> @@ -9,7 +9,8 @@

>  #include <linux/backlight.h>

>  #include <linux/err.h>

>  #include <linux/fb.h>

> -#include <linux/gpio.h>

> +#include <linux/gpio.h> /* Only for legacy support */

> +#include <linux/gpio/consumer.h>

>  #include <linux/init.h>

>  #include <linux/kernel.h>

>  #include <linux/module.h>

> @@ -23,7 +24,7 @@ struct gpio_backlight {

>  	struct device *dev;

>  	struct device *fbdev;

>  

> -	int gpio;

> +	struct gpio_desc *gpiod;

>  	int active;

>  	int def_value;

>  };

> @@ -38,8 +39,8 @@ static int gpio_backlight_update_status(struct backlight_device *bl)

>  	    bl->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK))

>  		brightness = 0;

>  

> -	gpio_set_value_cansleep(gbl->gpio,

> -				brightness ? gbl->active : !gbl->active);

> +	gpiod_set_value_cansleep(gbl->gpiod,

> +				 brightness ? gbl->active : !gbl->active);

>  

>  	return 0;

>  }

> @@ -61,23 +62,27 @@ static const struct backlight_ops gpio_backlight_ops = {

>  static int gpio_backlight_probe_dt(struct platform_device *pdev,

>  				   struct gpio_backlight *gbl)

>  {

> -	struct device_node *np = pdev->dev.of_node;

> -	enum of_gpio_flags gpio_flags;

> +	struct device *dev = &pdev->dev;

> +	struct device_node *np = dev->of_node;

> +	enum gpiod_flags flags;

> +	int ret;

> +

> +	gbl->def_value = of_property_read_bool(np, "default-on");

> +	flags = gbl->def_value ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;

> +	/* GPIO descriptors keep track of inversion */

> +	gbl->active = 1;

>  

> -	gbl->gpio = of_get_gpio_flags(np, 0, &gpio_flags);

> +	gbl->gpiod = devm_gpiod_get(dev, NULL, flags);

> +	if (IS_ERR(gbl->gpiod)) {

> +		ret = PTR_ERR(gbl->gpiod);

>  

> -	if (!gpio_is_valid(gbl->gpio)) {

> -		if (gbl->gpio != -EPROBE_DEFER) {

> -			dev_err(&pdev->dev,

> +		if (ret != -EPROBE_DEFER) {

> +			dev_err(dev,

>  				"Error: The gpios parameter is missing or invalid.\n");

>  		}

> -		return gbl->gpio;

> +		return ret;

>  	}

>  

> -	gbl->active = (gpio_flags & OF_GPIO_ACTIVE_LOW) ? 0 : 1;

> -

> -	gbl->def_value = of_property_read_bool(np, "default-on");

> -

>  	return 0;

>  }

>  

> @@ -89,7 +94,6 @@ static int gpio_backlight_probe(struct platform_device *pdev)

>  	struct backlight_device *bl;

>  	struct gpio_backlight *gbl;

>  	struct device_node *np = pdev->dev.of_node;

> -	unsigned long flags = GPIOF_DIR_OUT;

>  	int ret;

>  

>  	if (!pdata && !np) {

> @@ -109,22 +113,33 @@ static int gpio_backlight_probe(struct platform_device *pdev)

>  		if (ret)

>  			return ret;

>  	} else {

> +		/*

> +		 * Legacy platform data GPIO retrieveal. Do not expand

> +		 * the use of this code path, currently only used by one

> +		 * SH board.

> +		 */

> +		unsigned long flags = GPIOF_DIR_OUT;

> +

>  		gbl->fbdev = pdata->fbdev;

> -		gbl->gpio = pdata->gpio;

>  		gbl->active = pdata->active_low ? 0 : 1;

>  		gbl->def_value = pdata->def_value;

> -	}

> -

> -	if (gbl->active)

> -		flags |= gbl->def_value ? GPIOF_INIT_HIGH : GPIOF_INIT_LOW;

> -	else

> -		flags |= gbl->def_value ? GPIOF_INIT_LOW : GPIOF_INIT_HIGH;

>  

> -	ret = devm_gpio_request_one(gbl->dev, gbl->gpio, flags,

> -				    pdata ? pdata->name : "backlight");

> -	if (ret < 0) {

> -		dev_err(&pdev->dev, "unable to request GPIO\n");

> -		return ret;

> +		if (gbl->active)

> +			flags |= gbl->def_value ?

> +				GPIOF_INIT_HIGH : GPIOF_INIT_LOW;

> +		else

> +			flags |= gbl->def_value ?

> +				GPIOF_INIT_LOW : GPIOF_INIT_HIGH;

> +

> +		ret = devm_gpio_request_one(gbl->dev, pdata->gpio, flags,

> +					    pdata ? pdata->name : "backlight");

> +		if (ret < 0) {

> +			dev_err(&pdev->dev, "unable to request GPIO\n");

> +			return ret;

> +		}

> +		gbl->gpiod = gpio_to_desc(pdata->gpio);

> +		if (!gbl->gpiod)

> +			return -EINVAL;

>  	}

>  

>  	memset(&props, 0, sizeof(props));


-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog
diff mbox series

Patch

diff --git a/drivers/video/backlight/gpio_backlight.c b/drivers/video/backlight/gpio_backlight.c
index 18134416b154..5ffaff1e4142 100644
--- a/drivers/video/backlight/gpio_backlight.c
+++ b/drivers/video/backlight/gpio_backlight.c
@@ -9,7 +9,8 @@ 
 #include <linux/backlight.h>
 #include <linux/err.h>
 #include <linux/fb.h>
-#include <linux/gpio.h>
+#include <linux/gpio.h> /* Only for legacy support */
+#include <linux/gpio/consumer.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
@@ -23,7 +24,7 @@  struct gpio_backlight {
 	struct device *dev;
 	struct device *fbdev;
 
-	int gpio;
+	struct gpio_desc *gpiod;
 	int active;
 	int def_value;
 };
@@ -38,8 +39,8 @@  static int gpio_backlight_update_status(struct backlight_device *bl)
 	    bl->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK))
 		brightness = 0;
 
-	gpio_set_value_cansleep(gbl->gpio,
-				brightness ? gbl->active : !gbl->active);
+	gpiod_set_value_cansleep(gbl->gpiod,
+				 brightness ? gbl->active : !gbl->active);
 
 	return 0;
 }
@@ -61,23 +62,27 @@  static const struct backlight_ops gpio_backlight_ops = {
 static int gpio_backlight_probe_dt(struct platform_device *pdev,
 				   struct gpio_backlight *gbl)
 {
-	struct device_node *np = pdev->dev.of_node;
-	enum of_gpio_flags gpio_flags;
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	enum gpiod_flags flags;
+	int ret;
+
+	gbl->def_value = of_property_read_bool(np, "default-on");
+	flags = gbl->def_value ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
+	/* GPIO descriptors keep track of inversion */
+	gbl->active = 1;
 
-	gbl->gpio = of_get_gpio_flags(np, 0, &gpio_flags);
+	gbl->gpiod = devm_gpiod_get(dev, NULL, flags);
+	if (IS_ERR(gbl->gpiod)) {
+		ret = PTR_ERR(gbl->gpiod);
 
-	if (!gpio_is_valid(gbl->gpio)) {
-		if (gbl->gpio != -EPROBE_DEFER) {
-			dev_err(&pdev->dev,
+		if (ret != -EPROBE_DEFER) {
+			dev_err(dev,
 				"Error: The gpios parameter is missing or invalid.\n");
 		}
-		return gbl->gpio;
+		return ret;
 	}
 
-	gbl->active = (gpio_flags & OF_GPIO_ACTIVE_LOW) ? 0 : 1;
-
-	gbl->def_value = of_property_read_bool(np, "default-on");
-
 	return 0;
 }
 
@@ -89,7 +94,6 @@  static int gpio_backlight_probe(struct platform_device *pdev)
 	struct backlight_device *bl;
 	struct gpio_backlight *gbl;
 	struct device_node *np = pdev->dev.of_node;
-	unsigned long flags = GPIOF_DIR_OUT;
 	int ret;
 
 	if (!pdata && !np) {
@@ -109,22 +113,33 @@  static int gpio_backlight_probe(struct platform_device *pdev)
 		if (ret)
 			return ret;
 	} else {
+		/*
+		 * Legacy platform data GPIO retrieveal. Do not expand
+		 * the use of this code path, currently only used by one
+		 * SH board.
+		 */
+		unsigned long flags = GPIOF_DIR_OUT;
+
 		gbl->fbdev = pdata->fbdev;
-		gbl->gpio = pdata->gpio;
 		gbl->active = pdata->active_low ? 0 : 1;
 		gbl->def_value = pdata->def_value;
-	}
-
-	if (gbl->active)
-		flags |= gbl->def_value ? GPIOF_INIT_HIGH : GPIOF_INIT_LOW;
-	else
-		flags |= gbl->def_value ? GPIOF_INIT_LOW : GPIOF_INIT_HIGH;
 
-	ret = devm_gpio_request_one(gbl->dev, gbl->gpio, flags,
-				    pdata ? pdata->name : "backlight");
-	if (ret < 0) {
-		dev_err(&pdev->dev, "unable to request GPIO\n");
-		return ret;
+		if (gbl->active)
+			flags |= gbl->def_value ?
+				GPIOF_INIT_HIGH : GPIOF_INIT_LOW;
+		else
+			flags |= gbl->def_value ?
+				GPIOF_INIT_LOW : GPIOF_INIT_HIGH;
+
+		ret = devm_gpio_request_one(gbl->dev, pdata->gpio, flags,
+					    pdata ? pdata->name : "backlight");
+		if (ret < 0) {
+			dev_err(&pdev->dev, "unable to request GPIO\n");
+			return ret;
+		}
+		gbl->gpiod = gpio_to_desc(pdata->gpio);
+		if (!gbl->gpiod)
+			return -EINVAL;
 	}
 
 	memset(&props, 0, sizeof(props));