lkml.org 
[lkml]   [2019]   [Jun]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH] gpio: Fix return value mismatch of function gpiod_get_from_of_node()
On Wed, 19 Jun 2019 at 11:56, Waibel Georg
<Georg.Waibel@sensor-technik.de> wrote:
>
> In case the requested gpio property is not found in the device tree, some
> callers of gpiod_get_from_of_node() expect a return value of NULL, others
> expect -ENOENT.
> In particular devm_fwnode_get_index_gpiod_from_child() expects -ENOENT.
> Currently it gets a NULL, which breaks the loop that tries all
> gpio_suffixes. The result is that a gpio property is not found, even
> though it is there.
>
> This patch changes gpiod_get_from_of_node() to return -ENOENT instead
> of NULL when the requested gpio property is not found in the device
> tree. Additionally it modifies all calling functions to properly
> evaluate the return value.
>
> Another approach would be to leave the return value of
> gpiod_get_from_of_node() as is and fix the bug in
> devm_fwnode_get_index_gpiod_from_child(). Other callers would still need
> to be reworked. The effort would be the same as with the chosen solution.
>
> Signed-off-by: Georg Waibel <georg.waibel@sensor-technik.de>
> ---
> drivers/gpio/gpiolib.c | 6 +-----
> drivers/regulator/da9211-regulator.c | 2 ++
> drivers/regulator/s2mps11.c | 4 +++-
> drivers/regulator/s5m8767.c | 4 +++-
> drivers/regulator/tps65090-regulator.c | 7 ++++---
> 5 files changed, 13 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
> index e013d417a936..be1d1d2f8aaa 100644
> --- a/drivers/gpio/gpiolib.c
> +++ b/drivers/gpio/gpiolib.c
> @@ -4244,8 +4244,7 @@ EXPORT_SYMBOL_GPL(gpiod_get_index);
> *
> * Returns:
> * On successful request the GPIO pin is configured in accordance with
> - * provided @dflags. If the node does not have the requested GPIO
> - * property, NULL is returned.
> + * provided @dflags.
> *
> * In case of error an ERR_PTR() is returned.
> */
> @@ -4267,9 +4266,6 @@ struct gpio_desc *gpiod_get_from_of_node(struct device_node *node,
> index, &flags);
>
> if (!desc || IS_ERR(desc)) {
> - /* If it is not there, just return NULL */
> - if (PTR_ERR(desc) == -ENOENT)
> - return NULL;
> return desc;
> }
>
> diff --git a/drivers/regulator/da9211-regulator.c b/drivers/regulator/da9211-regulator.c
> index da37b4ccd834..0309823d2c72 100644
> --- a/drivers/regulator/da9211-regulator.c
> +++ b/drivers/regulator/da9211-regulator.c
> @@ -289,6 +289,8 @@ static struct da9211_pdata *da9211_parse_regulators_dt(
> 0,
> GPIOD_OUT_HIGH | GPIOD_FLAGS_BIT_NONEXCLUSIVE,
> "da9211-enable");
> + if (IS_ERR(pdata->gpiod_ren[n]))
> + pdata->gpiod_ren[n] = NULL;
> n++;
> }
>
> diff --git a/drivers/regulator/s2mps11.c b/drivers/regulator/s2mps11.c
> index 134c62db36c5..b518a81f75a3 100644
> --- a/drivers/regulator/s2mps11.c
> +++ b/drivers/regulator/s2mps11.c
> @@ -821,7 +821,9 @@ static void s2mps14_pmic_dt_parse_ext_control_gpio(struct platform_device *pdev,
> 0,
> GPIOD_OUT_HIGH | GPIOD_FLAGS_BIT_NONEXCLUSIVE,
> "s2mps11-regulator");
> - if (IS_ERR(gpio[reg])) {
> + if (PTR_ERR(gpio[reg]) == -ENOENT)
> + gpio[reg] = NULL;
> + else if (IS_ERR(gpio[reg])) {
> dev_err(&pdev->dev, "Failed to get control GPIO for %d/%s\n",
> reg, rdata[reg].name);
> continue;
> diff --git a/drivers/regulator/s5m8767.c b/drivers/regulator/s5m8767.c
> index bb9d1a083299..6ca27e9d5ef7 100644
> --- a/drivers/regulator/s5m8767.c
> +++ b/drivers/regulator/s5m8767.c
> @@ -574,7 +574,9 @@ static int s5m8767_pmic_dt_parse_pdata(struct platform_device *pdev,
> 0,
> GPIOD_OUT_HIGH | GPIOD_FLAGS_BIT_NONEXCLUSIVE,
> "s5m8767");
> - if (IS_ERR(rdata->ext_control_gpiod))
> + if (PTR_ERR(rdata->ext_control_gpiod) == -ENOENT)
> + rdata->ext_control_gpiod = NULL;
> + else if (IS_ERR(rdata->ext_control_gpiod))
> return PTR_ERR(rdata->ext_control_gpiod);
>

For s2mps11 and s5m8767 bits:
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>

The s2mps11 code brought a bug to my attention so you might rebase on top of it.

Best regards,
Krzysztof

\
 
 \ /
  Last update: 2019-06-19 14:46    [W:0.059 / U:1.072 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site