diff mbox series

[v4,2/2] gpiolib: check the 'ngpios' property in core gpiolib code

Message ID 20211202134034.14048-2-brgl@bgdev.pl
State New
Headers show
Series [v4,1/2] gpiolib: improve coding style for local variables | expand

Commit Message

Bartosz Golaszewski Dec. 2, 2021, 1:40 p.m. UTC 
Several drivers read the 'ngpios' device property on their own, but
since it's defined as a standard GPIO property in the device tree bindings
anyway, it's a good candidate for generalization. If the driver didn't
set its gc->ngpio, try to read the 'ngpios' property from the GPIO
device's firmware node before bailing out.

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
---
v1 -> v2:
- use device_property_read_u32() instead of fwnode_property_read_u32()
- reverse the error check logic

v2 -> v3:
- don't shadow errors other than -ENODATA in device_property_read_u32()

v3 -> v4:
- also make sure we return -EINVAL when the device 'ngpios' property is
  set to 0 (thanks Andy!)

 drivers/gpio/gpiolib.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

Comments

Andy Shevchenko Dec. 2, 2021, 3:37 p.m. UTC | #1 
On Thu, Dec 02, 2021 at 02:40:34PM +0100, Bartosz Golaszewski wrote:
> Several drivers read the 'ngpios' device property on their own, but
> since it's defined as a standard GPIO property in the device tree bindings
> anyway, it's a good candidate for generalization. If the driver didn't
> set its gc->ngpio, try to read the 'ngpios' property from the GPIO
> device's firmware node before bailing out.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
One nit-pick below (you may amend it when applying)

> Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
> Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
> ---
> v1 -> v2:
> - use device_property_read_u32() instead of fwnode_property_read_u32()
> - reverse the error check logic
> 
> v2 -> v3:
> - don't shadow errors other than -ENODATA in device_property_read_u32()
> 
> v3 -> v4:
> - also make sure we return -EINVAL when the device 'ngpios' property is
>   set to 0 (thanks Andy!)
> 
>  drivers/gpio/gpiolib.c | 21 +++++++++++++++++++++
>  1 file changed, 21 insertions(+)
> 
> diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
> index ede8b8a7aa18..bd9b8cb53476 100644
> --- a/drivers/gpio/gpiolib.c
> +++ b/drivers/gpio/gpiolib.c
> @@ -599,6 +599,7 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
>  	int base = gc->base;
>  	unsigned int i;
>  	int ret = 0;
> +	u32 ngpios;
>  
>  	/*
>  	 * First: allocate and populate the internal stat container, and
> @@ -646,6 +647,26 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
>  		goto err_free_dev_name;
>  	}
>  
> +	/*
> +	 * Try the device properties if the driver didn't supply the number
> +	 * of GPIO lines.
> +	 */
> +	if (gc->ngpio == 0) {
> +		ret = device_property_read_u32(&gdev->dev, "ngpios", &ngpios);
> +		if (ret == -ENODATA)
> +			/*
> +			 * -ENODATA means that there is no property found and
> +			 * we want to issue the error message to the user.
> +			 * Besides that, we want to return different error code
> +			 * to state that supplied value is not valid.

> +			 * */

First '* ' is not needed.

> +			ngpios = 0;
> +		else if (ret)
> +			goto err_free_descs;
> +
> +		gc->ngpio = ngpios;
> +	}
> +
>  	if (gc->ngpio == 0) {
>  		chip_err(gc, "tried to insert a GPIO chip with zero lines\n");
>  		ret = -EINVAL;
> -- 
> 2.25.1
>
Bartosz Golaszewski Dec. 2, 2021, 3:48 p.m. UTC | #2 
On Thu, Dec 2, 2021 at 4:38 PM Andy Shevchenko
<andriy.shevchenko@linux.intel.com> wrote:
>
> On Thu, Dec 02, 2021 at 02:40:34PM +0100, Bartosz Golaszewski wrote:
> > Several drivers read the 'ngpios' device property on their own, but
> > since it's defined as a standard GPIO property in the device tree bindings
> > anyway, it's a good candidate for generalization. If the driver didn't
> > set its gc->ngpio, try to read the 'ngpios' property from the GPIO
> > device's firmware node before bailing out.
>
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> One nit-pick below (you may amend it when applying)
>
> > Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
> > Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> > Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
> > ---
> > v1 -> v2:
> > - use device_property_read_u32() instead of fwnode_property_read_u32()
> > - reverse the error check logic
> >
> > v2 -> v3:
> > - don't shadow errors other than -ENODATA in device_property_read_u32()
> >
> > v3 -> v4:
> > - also make sure we return -EINVAL when the device 'ngpios' property is
> >   set to 0 (thanks Andy!)
> >
> >  drivers/gpio/gpiolib.c | 21 +++++++++++++++++++++
> >  1 file changed, 21 insertions(+)
> >
> > diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
> > index ede8b8a7aa18..bd9b8cb53476 100644
> > --- a/drivers/gpio/gpiolib.c
> > +++ b/drivers/gpio/gpiolib.c
> > @@ -599,6 +599,7 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
> >       int base = gc->base;
> >       unsigned int i;
> >       int ret = 0;
> > +     u32 ngpios;
> >
> >       /*
> >        * First: allocate and populate the internal stat container, and
> > @@ -646,6 +647,26 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
> >               goto err_free_dev_name;
> >       }
> >
> > +     /*
> > +      * Try the device properties if the driver didn't supply the number
> > +      * of GPIO lines.
> > +      */
> > +     if (gc->ngpio == 0) {
> > +             ret = device_property_read_u32(&gdev->dev, "ngpios", &ngpios);
> > +             if (ret == -ENODATA)
> > +                     /*
> > +                      * -ENODATA means that there is no property found and
> > +                      * we want to issue the error message to the user.
> > +                      * Besides that, we want to return different error code
> > +                      * to state that supplied value is not valid.
>
> > +                      * */
>
> First '* ' is not needed.
>

I'll fix it when applying.

Bart
Bartosz Golaszewski Dec. 6, 2021, 3:01 p.m. UTC | #3 
On Thu, Dec 2, 2021 at 2:40 PM Bartosz Golaszewski <brgl@bgdev.pl> wrote:
>
> Several drivers read the 'ngpios' device property on their own, but
> since it's defined as a standard GPIO property in the device tree bindings
> anyway, it's a good candidate for generalization. If the driver didn't
> set its gc->ngpio, try to read the 'ngpios' property from the GPIO
> device's firmware node before bailing out.
>
> Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
> Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
> ---
> v1 -> v2:
> - use device_property_read_u32() instead of fwnode_property_read_u32()
> - reverse the error check logic
>
> v2 -> v3:
> - don't shadow errors other than -ENODATA in device_property_read_u32()
>
> v3 -> v4:
> - also make sure we return -EINVAL when the device 'ngpios' property is
>   set to 0 (thanks Andy!)
>
>  drivers/gpio/gpiolib.c | 21 +++++++++++++++++++++
>  1 file changed, 21 insertions(+)
>
> diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
> index ede8b8a7aa18..bd9b8cb53476 100644
> --- a/drivers/gpio/gpiolib.c
> +++ b/drivers/gpio/gpiolib.c
> @@ -599,6 +599,7 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
>         int base = gc->base;
>         unsigned int i;
>         int ret = 0;
> +       u32 ngpios;
>
>         /*
>          * First: allocate and populate the internal stat container, and
> @@ -646,6 +647,26 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
>                 goto err_free_dev_name;
>         }
>
> +       /*
> +        * Try the device properties if the driver didn't supply the number
> +        * of GPIO lines.
> +        */
> +       if (gc->ngpio == 0) {
> +               ret = device_property_read_u32(&gdev->dev, "ngpios", &ngpios);
> +               if (ret == -ENODATA)
> +                       /*
> +                        * -ENODATA means that there is no property found and
> +                        * we want to issue the error message to the user.
> +                        * Besides that, we want to return different error code
> +                        * to state that supplied value is not valid.
> +                        * */
> +                       ngpios = 0;
> +               else if (ret)
> +                       goto err_free_descs;
> +
> +               gc->ngpio = ngpios;
> +       }
> +
>         if (gc->ngpio == 0) {
>                 chip_err(gc, "tried to insert a GPIO chip with zero lines\n");
>                 ret = -EINVAL;
> --
> 2.25.1
>

Queued for next.

Bart
diff mbox series

Patch

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index ede8b8a7aa18..bd9b8cb53476 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -599,6 +599,7 @@  int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
 	int base = gc->base;
 	unsigned int i;
 	int ret = 0;
+	u32 ngpios;
 
 	/*
 	 * First: allocate and populate the internal stat container, and
@@ -646,6 +647,26 @@  int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
 		goto err_free_dev_name;
 	}
 
+	/*
+	 * Try the device properties if the driver didn't supply the number
+	 * of GPIO lines.
+	 */
+	if (gc->ngpio == 0) {
+		ret = device_property_read_u32(&gdev->dev, "ngpios", &ngpios);
+		if (ret == -ENODATA)
+			/*
+			 * -ENODATA means that there is no property found and
+			 * we want to issue the error message to the user.
+			 * Besides that, we want to return different error code
+			 * to state that supplied value is not valid.
+			 * */
+			ngpios = 0;
+		else if (ret)
+			goto err_free_descs;
+
+		gc->ngpio = ngpios;
+	}
+
 	if (gc->ngpio == 0) {
 		chip_err(gc, "tried to insert a GPIO chip with zero lines\n");
 		ret = -EINVAL;