[PATCH] pinctrl: vt8500: Ensure value reg is updated when setting direction

[PATCH] pinctrl: vt8500: Ensure value reg is updated when setting direction

[Alexey Charkov]

Current code only touches the direction register when setting direction
to output, which breaks logic like

echo high > /sys/class/gpio/gpio0/direction

which is expected to also set the value. This patch also adds a call
to update the value register when setting direction to output.

Signed-off-by: Alexey Charkov <alchark@gmail.com>
---
 drivers/pinctrl/vt8500/pinctrl-wmt.c | 23 ++++++++++++-----------
 1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/drivers/pinctrl/vt8500/pinctrl-wmt.c b/drivers/pinctrl/vt8500/pinctrl-wmt.c
index 9802b67..2c61281 100644
--- a/drivers/pinctrl/vt8500/pinctrl-wmt.c
+++ b/drivers/pinctrl/vt8500/pinctrl-wmt.c
@@ -523,17 +523,6 @@ static int wmt_gpio_get_direction(struct gpio_chip *chip, unsigned offset)
 		return GPIOF_DIR_IN;
 }
 
-static int wmt_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
-{
-	return pinctrl_gpio_direction_input(chip->base + offset);
-}
-
-static int wmt_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
-				     int value)
-{
-	return pinctrl_gpio_direction_output(chip->base + offset);
-}
-
 static int wmt_gpio_get_value(struct gpio_chip *chip, unsigned offset)
 {
 	struct wmt_pinctrl_data *data = dev_get_drvdata(chip->dev);
@@ -568,6 +557,18 @@ static void wmt_gpio_set_value(struct gpio_chip *chip, unsigned offset,
 		wmt_clearbits(data, reg_data_out, BIT(bit));
 }
 
+static int wmt_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
+{
+	return pinctrl_gpio_direction_input(chip->base + offset);
+}
+
+static int wmt_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
+				     int value)
+{
+	wmt_gpio_set_value(chip, offset, value);
+	return pinctrl_gpio_direction_output(chip->base + offset);
+}
+
 static struct gpio_chip wmt_gpio_chip = {
 	.label = "gpio-wmt",
 	.owner = THIS_MODULE,
-- 
1.9.1

Re: [PATCH] pinctrl: vt8500: Ensure value reg is updated when setting direction

[Tony Prisk]

On 30/04/14 07:42, Alexey Charkov wrote:
> Current code only touches the direction register when setting direction
> to output, which breaks logic like
>
> echo high > /sys/class/gpio/gpio0/direction
>
> which is expected to also set the value. This patch also adds a call
> to update the value register when setting direction to output.
>
> Signed-off-by: Alexey Charkov <alchark@gmail.com>
> ---
>   drivers/pinctrl/vt8500/pinctrl-wmt.c | 23 ++++++++++++-----------
>   1 file changed, 12 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/pinctrl/vt8500/pinctrl-wmt.c b/drivers/pinctrl/vt8500/pinctrl-wmt.c
> index 9802b67..2c61281 100644
> --- a/drivers/pinctrl/vt8500/pinctrl-wmt.c
> +++ b/drivers/pinctrl/vt8500/pinctrl-wmt.c
> @@ -523,17 +523,6 @@ static int wmt_gpio_get_direction(struct gpio_chip *chip, unsigned offset)
>   		return GPIOF_DIR_IN;
>   }
>   
> -static int wmt_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
> -{
> -	return pinctrl_gpio_direction_input(chip->base + offset);
> -}
> -
> -static int wmt_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
> -				     int value)
> -{
> -	return pinctrl_gpio_direction_output(chip->base + offset);
> -}
> -
>   static int wmt_gpio_get_value(struct gpio_chip *chip, unsigned offset)
>   {
>   	struct wmt_pinctrl_data *data = dev_get_drvdata(chip->dev);
> @@ -568,6 +557,18 @@ static void wmt_gpio_set_value(struct gpio_chip *chip, unsigned offset,
>   		wmt_clearbits(data, reg_data_out, BIT(bit));
>   }
>   
> +static int wmt_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
> +{
> +	return pinctrl_gpio_direction_input(chip->base + offset);
> +}
> +
> +static int wmt_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
> +				     int value)
> +{
> +	wmt_gpio_set_value(chip, offset, value);
> +	return pinctrl_gpio_direction_output(chip->base + offset);
> +}
> +
>   static struct gpio_chip wmt_gpio_chip = {
>   	.label = "gpio-wmt",
>   	.owner = THIS_MODULE,

Acked-by: Tony Prisk <linux@prisktech.co.nz>

Didn't notice that this was an option in the gpio documentation but it 
makes obvious sense.
Regards
Tony P

Re: [PATCH] pinctrl: vt8500: Ensure value reg is updated when setting direction

[Linus Walleij]

On Tue, Apr 29, 2014 at 9:42 PM, Alexey Charkov <alchark@gmail.com> wrote:

> Current code only touches the direction register when setting direction
> to output, which breaks logic like
>
> echo high > /sys/class/gpio/gpio0/direction
>
> which is expected to also set the value. This patch also adds a call
> to update the value register when setting direction to output.
>
> Signed-off-by: Alexey Charkov <alchark@gmail.com>

Patch applied for fixes with Tony's ACK.

Yours,
Linus Walleij