On Wed 2018-09-05 09:44:04, Michal Vokáč wrote:
> Hi Song,
> On 5.9.2018 04:34, Song Qiang wrote:
> >Some leds on our board are active low leds, which means these leds
> >are lighted when the corresponding gpio line is low, while the
> >original leds-gpio driver default all leds are active high leds.
> >This patch adds a devicetree node "light-state", whose value should
> >be "high" for active high leds and "low" for active low leds.
> >The default value is "high" for compatible for the original driver.
> >
> >Signed-off-by: Song Qiang <songqiang.1304521@xxxxxxxxx>
> >---
> > .../devicetree/bindings/leds/leds-gpio.txt | 15 +++++++++++
> > drivers/leds/leds-gpio.c | 25 +++++++++++++++++--
> > 2 files changed, 38 insertions(+), 2 deletions(-)
> >
> >diff --git a/Documentation/devicetree/bindings/leds/leds-gpio.txt b/Documentation/devicetree/bindings/leds/leds-gpio.txt
> >index a48dda268f81..0a8fad75c704 100644
> >--- a/Documentation/devicetree/bindings/leds/leds-gpio.txt
> >+++ b/Documentation/devicetree/bindings/leds/leds-gpio.txt
> >@@ -23,6 +23,9 @@ LED sub-node properties:
> > remains up.
> > - panic-indicator : (optional)
> > see Documentation/devicetree/bindings/leds/common.txt
> >+- light-state: (optional) Values should be "high" or "low", which indicates
> >+ the state of the GPIO pin when the led is on.
> >+ see Documentation/devicetree/bindings/leds/common.txt
> > Examples:
> >@@ -64,3 +67,15 @@ leds {
> > retain-state-suspended;
> > };
> > };
> >+
> >+leds {
> >+ compatible = "gpio-leds";
> >+
> >+ led0 {
> >+ label = "led0";
> >+ gpios = <&gpio1 19 GPIO_ACTIVE_HIGH>;
>
> With this patch you are introducing one more way to invert the logic.
> If your LED is active LOW, you should use GPIO_ACTIVE_LOW in your DT.
> All should work as expected then.
Exactly, GPIO subsystem already has ways to specify active-low and
active-high.
NAK.
Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
Attachment:
signature.asc
Description: Digital signature
