From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

struct gpio_chip now has callbacks for setting line values that return
an integer, allowing to indicate failures. Convert the driver to using
them.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Marek Behún <kabel@kernel.org>
---
Commit 98ce1eb1fd87e ("gpiolib: introduce gpio_chip setters that return
values") added new line setter callbacks to struct gpio_chip. They allow
to indicate failures to callers. We're in the process of converting all
GPIO controllers to using them before removing the old ones.
---
Changes since v1:
- renamed the variable `ret` to `err`

Arnd, I guess this can be merged by gpio subsystem maintainers.
Marek
---
 .../platform/cznic/turris-omnia-mcu-gpio.c    | 35 ++++++++++++-------
 1 file changed, 22 insertions(+), 13 deletions(-)

diff --git a/drivers/platform/cznic/turris-omnia-mcu-gpio.c b/drivers/platform/cznic/turris-omnia-mcu-gpio.c
index 5f35f7c5d5d7..dabdce113af2 100644
--- a/drivers/platform/cznic/turris-omnia-mcu-gpio.c
+++ b/drivers/platform/cznic/turris-omnia-mcu-gpio.c
@@ -438,27 +438,28 @@ static int omnia_gpio_get_multiple(struct gpio_chip *gc, unsigned long *mask,
 	return 0;
 }
 
-static void omnia_gpio_set(struct gpio_chip *gc, unsigned int offset, int value)
+static int omnia_gpio_set(struct gpio_chip *gc, unsigned int offset, int value)
 {
 	const struct omnia_gpio *gpio = &omnia_gpios[offset];
 	struct omnia_mcu *mcu = gpiochip_get_data(gc);
 	u16 val, mask;
 
 	if (!gpio->ctl_cmd)
-		return;
+		return -EINVAL;
 
 	mask = BIT(gpio->ctl_bit);
 	val = value ? mask : 0;
 
-	omnia_ctl_cmd(mcu, gpio->ctl_cmd, val, mask);
+	return omnia_ctl_cmd(mcu, gpio->ctl_cmd, val, mask);
 }
 
-static void omnia_gpio_set_multiple(struct gpio_chip *gc, unsigned long *mask,
-				    unsigned long *bits)
+static int omnia_gpio_set_multiple(struct gpio_chip *gc, unsigned long *mask,
+				   unsigned long *bits)
 {
 	unsigned long ctl = 0, ctl_mask = 0, ext_ctl = 0, ext_ctl_mask = 0;
 	struct omnia_mcu *mcu = gpiochip_get_data(gc);
 	unsigned int i;
+	int err;
 
 	for_each_set_bit(i, mask, ARRAY_SIZE(omnia_gpios)) {
 		unsigned long *field, *field_mask;
@@ -487,13 +488,21 @@ static void omnia_gpio_set_multiple(struct gpio_chip *gc, unsigned long *mask,
 
 	guard(mutex)(&mcu->lock);
 
-	if (ctl_mask)
-		omnia_ctl_cmd_locked(mcu, OMNIA_CMD_GENERAL_CONTROL,
-				     ctl, ctl_mask);
+	if (ctl_mask) {
+		err = omnia_ctl_cmd_locked(mcu, OMNIA_CMD_GENERAL_CONTROL,
+					   ctl, ctl_mask);
+		if (err)
+			return err;
+	}
+
+	if (ext_ctl_mask) {
+		err = omnia_ctl_cmd_locked(mcu, OMNIA_CMD_EXT_CONTROL,
+					   ext_ctl, ext_ctl_mask);
+		if (err)
+			return err;
+	}
 
-	if (ext_ctl_mask)
-		omnia_ctl_cmd_locked(mcu, OMNIA_CMD_EXT_CONTROL,
-				     ext_ctl, ext_ctl_mask);
+	return 0;
 }
 
 static bool omnia_gpio_available(struct omnia_mcu *mcu,
@@ -1014,8 +1023,8 @@ int omnia_mcu_register_gpiochip(struct omnia_mcu *mcu)
 	mcu->gc.direction_output = omnia_gpio_direction_output;
 	mcu->gc.get = omnia_gpio_get;
 	mcu->gc.get_multiple = omnia_gpio_get_multiple;
-	mcu->gc.set = omnia_gpio_set;
-	mcu->gc.set_multiple = omnia_gpio_set_multiple;
+	mcu->gc.set_rv = omnia_gpio_set;
+	mcu->gc.set_multiple_rv = omnia_gpio_set_multiple;
 	mcu->gc.init_valid_mask = omnia_gpio_init_valid_mask;
 	mcu->gc.can_sleep = true;
 	mcu->gc.names = omnia_mcu_gpio_names;
-- 
2.49.0

On Wed, Apr 9, 2025 at 11:12 PM Marek Behún <kabel@kernel.org> wrote:

> From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
>
> struct gpio_chip now has callbacks for setting line values that return
> an integer, allowing to indicate failures. Convert the driver to using
> them.
>
> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
> Signed-off-by: Marek Behún <kabel@kernel.org>

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

Yours,
Linus Walleij

On Wed, Apr 9, 2025 at 11:12 PM Marek Behún <kabel@kernel.org> wrote:
>
> From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
>
> struct gpio_chip now has callbacks for setting line values that return
> an integer, allowing to indicate failures. Convert the driver to using
> them.
>
> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
> Signed-off-by: Marek Behún <kabel@kernel.org>
> ---
> Commit 98ce1eb1fd87e ("gpiolib: introduce gpio_chip setters that return
> values") added new line setter callbacks to struct gpio_chip. They allow
> to indicate failures to callers. We're in the process of converting all
> GPIO controllers to using them before removing the old ones.
> ---

Can this be picked up into linux-next?

Bartosz