2019-02-20 10:54:21

by Thierry Reding

[permalink] [raw]
Subject: [PATCH] gpio: of: Restrict enable-gpio quirk to regulator-gpio

From: Thierry Reding <[email protected]>

Commit 0e7d6f940164 ("gpio: of: Apply regulator-gpio quirk only to
enable-gpios") breaks the device tree ABI specified in the device tree
bindings for fixed regulators (compatible "regulator-fixed"). According
to these bindings the polarity of the GPIO is exclusively controlled by
the presence or absence of the enable-active-high property. As such the
polarity quirk implemented in of_gpio_flags_quirks() must be applied to
the GPIO specified for fixed regulators.

However, commit 0e7d6f940164 ("gpio: of: Apply regulator-gpio quirk only
to enable-gpios") restricted the quirk to the enable-gpios property for
fixed regulators as well, whereas according to the commit message itself
it should only apply to "regulator-gpio" compatible device tree nodes.

Fix this by actually implementing what the offending commit intended,
which is to ensure that the quirk is applied to the GPIO specified by
the "enable-gpio" property for the "regulator-gpio" bindings only.

This fixes a regression on Jetson TX1 where the fixed regulator for the
HDMI +5V pin relies on the flags quirk for the proper polarity.

Fixes: 0e7d6f940164 ("gpio: of: Apply regulator-gpio quirk only to enable-gpios")
Signed-off-by: Thierry Reding <[email protected]>
---
drivers/gpio/gpiolib-of.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
index 1b4c741e0635..bddfc6102a50 100644
--- a/drivers/gpio/gpiolib-of.c
+++ b/drivers/gpio/gpiolib-of.c
@@ -84,10 +84,10 @@ static void of_gpio_flags_quirks(struct device_node *np,
* Note that active low is the default.
*/
if (IS_ENABLED(CONFIG_REGULATOR) &&
- !strcmp(propname, "enable-gpio") &&
(of_device_is_compatible(np, "regulator-fixed") ||
of_device_is_compatible(np, "reg-fixed-voltage") ||
- of_device_is_compatible(np, "regulator-gpio"))) {
+ (of_device_is_compatible(np, "regulator-gpio") &&
+ strcmp(propname, "enable-gpio") == 0))) {
/*
* The regulator GPIO handles are specified such that the
* presence or absence of "enable-active-high" solely controls
--
2.20.1



2019-02-20 11:18:28

by Marek Vasut

[permalink] [raw]
Subject: Re: [PATCH] gpio: of: Restrict enable-gpio quirk to regulator-gpio

On 2/20/19 11:52 AM, Thierry Reding wrote:
> From: Thierry Reding <[email protected]>
>
> Commit 0e7d6f940164 ("gpio: of: Apply regulator-gpio quirk only to
> enable-gpios") breaks the device tree ABI specified in the device tree
> bindings for fixed regulators (compatible "regulator-fixed"). According
> to these bindings the polarity of the GPIO is exclusively controlled by
> the presence or absence of the enable-active-high property. As such the
> polarity quirk implemented in of_gpio_flags_quirks() must be applied to
> the GPIO specified for fixed regulators.
>
> However, commit 0e7d6f940164 ("gpio: of: Apply regulator-gpio quirk only
> to enable-gpios") restricted the quirk to the enable-gpios property for
> fixed regulators as well, whereas according to the commit message itself
> it should only apply to "regulator-gpio" compatible device tree nodes.
>
> Fix this by actually implementing what the offending commit intended,
> which is to ensure that the quirk is applied to the GPIO specified by
> the "enable-gpio" property for the "regulator-gpio" bindings only.
>
> This fixes a regression on Jetson TX1 where the fixed regulator for the
> HDMI +5V pin relies on the flags quirk for the proper polarity.
>
> Fixes: 0e7d6f940164 ("gpio: of: Apply regulator-gpio quirk only to enable-gpios")
> Signed-off-by: Thierry Reding <[email protected]>
> ---
> drivers/gpio/gpiolib-of.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
> index 1b4c741e0635..bddfc6102a50 100644
> --- a/drivers/gpio/gpiolib-of.c
> +++ b/drivers/gpio/gpiolib-of.c
> @@ -84,10 +84,10 @@ static void of_gpio_flags_quirks(struct device_node *np,
> * Note that active low is the default.
> */
> if (IS_ENABLED(CONFIG_REGULATOR) &&
> - !strcmp(propname, "enable-gpio") &&
> (of_device_is_compatible(np, "regulator-fixed") ||
> of_device_is_compatible(np, "reg-fixed-voltage") ||
> - of_device_is_compatible(np, "regulator-gpio"))) {
> + (of_device_is_compatible(np, "regulator-gpio") &&
> + strcmp(propname, "enable-gpio") == 0))) {
> /*
> * The regulator GPIO handles are specified such that the
> * presence or absence of "enable-active-high" solely controls

On R8A7795 Salvator-XS
Tested-by: Marek Vasut <[email protected]>

--
Best regards,
Marek Vasut

2019-02-21 12:10:53

by Linus Walleij

[permalink] [raw]
Subject: Re: [PATCH] gpio: of: Restrict enable-gpio quirk to regulator-gpio

On Wed, Feb 20, 2019 at 11:52 AM Thierry Reding
<[email protected]> wrote:

> From: Thierry Reding <[email protected]>
>
> Commit 0e7d6f940164 ("gpio: of: Apply regulator-gpio quirk only to
> enable-gpios") breaks the device tree ABI specified in the device tree
> bindings for fixed regulators (compatible "regulator-fixed"). According
> to these bindings the polarity of the GPIO is exclusively controlled by
> the presence or absence of the enable-active-high property. As such the
> polarity quirk implemented in of_gpio_flags_quirks() must be applied to
> the GPIO specified for fixed regulators.
>
> However, commit 0e7d6f940164 ("gpio: of: Apply regulator-gpio quirk only
> to enable-gpios") restricted the quirk to the enable-gpios property for
> fixed regulators as well, whereas according to the commit message itself
> it should only apply to "regulator-gpio" compatible device tree nodes.
>
> Fix this by actually implementing what the offending commit intended,
> which is to ensure that the quirk is applied to the GPIO specified by
> the "enable-gpio" property for the "regulator-gpio" bindings only.
>
> This fixes a regression on Jetson TX1 where the fixed regulator for the
> HDMI +5V pin relies on the flags quirk for the proper polarity.
>
> Fixes: 0e7d6f940164 ("gpio: of: Apply regulator-gpio quirk only to enable-gpios")
> Signed-off-by: Thierry Reding <[email protected]>

Patch applied with Marek's tested-by, thanks for thorough commit
message and helping out in sorting out this mess we've built
up over the years.

Yours,
Linus Walleij