diff mbox

[6/9] gpiolib-of: Reuse 'line-name' from DT as gpio descriptor name

Message ID 1437125570-28623-7-git-send-email-mpa@pengutronix.de (mailing list archive)
State New, archived
Headers show

Commit Message

Markus Pargmann July 17, 2015, 9:32 a.m. UTC
The DT describes gpios with subnodes. These subnodes can contain a
property 'line-name'. This information can be useful in other areas
where we want to identify a GPIO by its name.

This patch stores the line-name in the gpio descriptor.

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
---
 drivers/gpio/gpiolib-of.c | 29 ++++++++++++++++++++---------
 1 file changed, 20 insertions(+), 9 deletions(-)

Comments

Johan Hovold July 28, 2015, 9:31 a.m. UTC | #1
On Fri, Jul 17, 2015 at 11:32:47AM +0200, Markus Pargmann wrote:
> The DT describes gpios with subnodes. These subnodes can contain a
> property 'line-name'. This information can be useful in other areas
> where we want to identify a GPIO by its name.
> 
> This patch stores the line-name in the gpio descriptor.
> 
> Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
> ---
>  drivers/gpio/gpiolib-of.c | 29 ++++++++++++++++++++---------
>  1 file changed, 20 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
> index 64950591a764..cefc665a558c 100644
> --- a/drivers/gpio/gpiolib-of.c
> +++ b/drivers/gpio/gpiolib-of.c
> @@ -184,11 +184,6 @@ static struct gpio_desc *of_parse_gpio(struct device_node *np,
>  		*dflags |= GPIOD_OUT_LOW;
>  	else if (of_property_read_bool(np, "output-high"))
>  		*dflags |= GPIOD_OUT_HIGH;
> -	else {
> -		pr_warn("GPIO line %d (%s): no hogging state specified, bailing out\n",
> -			desc_to_gpio(gg_data.out_gpio), np->name);
> -		return ERR_PTR(-EINVAL);
> -	}
>
>  	if (name && of_property_read_string(np, "line-name", name))
>  		*name = np->name;
> @@ -214,15 +209,31 @@ static void of_gpiochip_scan_gpios(struct gpio_chip *chip)
>  
>  	for_each_child_of_node(chip->of_node, np) {
>  		const char *name = NULL;
> -		if (!of_property_read_bool(np, "gpio-hog"))
> -			continue;
> +		struct gpio_desc *name_desc;
>  
>  		desc = of_parse_gpio(np, &name, &lflags, &dflags);
>  		if (IS_ERR(desc))
>  			continue;
>  
> -		if (gpiod_hog(desc, name, lflags, dflags))
> -			continue;
> +		if (name) {
> +			name_desc = gpio_name_to_desc(name);
> +			if (name_desc)
> +				pr_err("GPIO name collision for '%s' detected at GPIO line %d (%s)\n",
> +				       name, desc_to_gpio(desc), np->name);
> +			else
> +				desc->name = name;

This will introduce a regression. As I mentioned in a comment on an
earlier patch, of_get_gpio_hog falls back to using the node name and
those need not be unique.

Johan
Markus Pargmann July 29, 2015, 6:52 a.m. UTC | #2
On Tue, Jul 28, 2015 at 11:31:05AM +0200, Johan Hovold wrote:
> On Fri, Jul 17, 2015 at 11:32:47AM +0200, Markus Pargmann wrote:
> > The DT describes gpios with subnodes. These subnodes can contain a
> > property 'line-name'. This information can be useful in other areas
> > where we want to identify a GPIO by its name.
> > 
> > This patch stores the line-name in the gpio descriptor.
> > 
> > Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
> > ---
> >  drivers/gpio/gpiolib-of.c | 29 ++++++++++++++++++++---------
> >  1 file changed, 20 insertions(+), 9 deletions(-)
> > 
> > diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
> > index 64950591a764..cefc665a558c 100644
> > --- a/drivers/gpio/gpiolib-of.c
> > +++ b/drivers/gpio/gpiolib-of.c
> > @@ -184,11 +184,6 @@ static struct gpio_desc *of_parse_gpio(struct device_node *np,
> >  		*dflags |= GPIOD_OUT_LOW;
> >  	else if (of_property_read_bool(np, "output-high"))
> >  		*dflags |= GPIOD_OUT_HIGH;
> > -	else {
> > -		pr_warn("GPIO line %d (%s): no hogging state specified, bailing out\n",
> > -			desc_to_gpio(gg_data.out_gpio), np->name);
> > -		return ERR_PTR(-EINVAL);
> > -	}
> >
> >  	if (name && of_property_read_string(np, "line-name", name))
> >  		*name = np->name;
> > @@ -214,15 +209,31 @@ static void of_gpiochip_scan_gpios(struct gpio_chip *chip)
> >  
> >  	for_each_child_of_node(chip->of_node, np) {
> >  		const char *name = NULL;
> > -		if (!of_property_read_bool(np, "gpio-hog"))
> > -			continue;
> > +		struct gpio_desc *name_desc;
> >  
> >  		desc = of_parse_gpio(np, &name, &lflags, &dflags);
> >  		if (IS_ERR(desc))
> >  			continue;
> >  
> > -		if (gpiod_hog(desc, name, lflags, dflags))
> > -			continue;
> > +		if (name) {
> > +			name_desc = gpio_name_to_desc(name);
> > +			if (name_desc)
> > +				pr_err("GPIO name collision for '%s' detected at GPIO line %d (%s)\n",
> > +				       name, desc_to_gpio(desc), np->name);
> > +			else
> > +				desc->name = name;
> 
> This will introduce a regression. As I mentioned in a comment on an
> earlier patch, of_get_gpio_hog falls back to using the node name and
> those need not be unique.

Yes, will fix this as well.

Thanks,

Markus

> 
> Johan
>
diff mbox

Patch

diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
index 64950591a764..cefc665a558c 100644
--- a/drivers/gpio/gpiolib-of.c
+++ b/drivers/gpio/gpiolib-of.c
@@ -184,11 +184,6 @@  static struct gpio_desc *of_parse_gpio(struct device_node *np,
 		*dflags |= GPIOD_OUT_LOW;
 	else if (of_property_read_bool(np, "output-high"))
 		*dflags |= GPIOD_OUT_HIGH;
-	else {
-		pr_warn("GPIO line %d (%s): no hogging state specified, bailing out\n",
-			desc_to_gpio(gg_data.out_gpio), np->name);
-		return ERR_PTR(-EINVAL);
-	}
 
 	if (name && of_property_read_string(np, "line-name", name))
 		*name = np->name;
@@ -214,15 +209,31 @@  static void of_gpiochip_scan_gpios(struct gpio_chip *chip)
 
 	for_each_child_of_node(chip->of_node, np) {
 		const char *name = NULL;
-		if (!of_property_read_bool(np, "gpio-hog"))
-			continue;
+		struct gpio_desc *name_desc;
 
 		desc = of_parse_gpio(np, &name, &lflags, &dflags);
 		if (IS_ERR(desc))
 			continue;
 
-		if (gpiod_hog(desc, name, lflags, dflags))
-			continue;
+		if (name) {
+			name_desc = gpio_name_to_desc(name);
+			if (name_desc)
+				pr_err("GPIO name collision for '%s' detected at GPIO line %d (%s)\n",
+				       name, desc_to_gpio(desc), np->name);
+			else
+				desc->name = name;
+		}
+
+		if (of_property_read_bool(np, "gpio-hog")) {
+			if (!dflags) {
+				pr_warn("GPIO line %d (%s): no hogging state specified, bailing out\n",
+					desc_to_gpio(desc), np->name);
+				continue;
+			}
+
+			if (gpiod_hog(desc, name, lflags, dflags))
+				continue;
+		}
 	}
 }