Hi Thierry, On Mon, Sep 22, 2014 at 1:40 PM, Thierry Reding <thierry.reding@xxxxxxxxx> wrote: > On Thu, Sep 18, 2014 at 11:20:40AM +0530, Ajay kumar wrote: >> Hi Tomi, >> >> On Wed, Sep 17, 2014 at 9:52 PM, Tomi Valkeinen <tomi.valkeinen@xxxxxx> wrote: >> > On 17/09/14 17:29, Ajay kumar wrote: >> >> Hi Tomi, >> >> >> >> Thanks for your comments. >> >> >> >> On Wed, Sep 17, 2014 at 5:22 PM, Tomi Valkeinen <tomi.valkeinen@xxxxxx> wrote: >> >>> On 27/08/14 17:39, Ajay Kumar wrote: >> >>>> Add documentation for DT properties supported by ps8622/ps8625 >> >>>> eDP-LVDS converter. >> >>>> >> >>>> Signed-off-by: Ajay Kumar <ajaykumar.rs@xxxxxxxxxxx> >> >>>> --- >> >>>> .../devicetree/bindings/video/bridge/ps8622.txt | 20 ++++++++++++++++++++ >> >>>> 1 file changed, 20 insertions(+) >> >>>> create mode 100644 Documentation/devicetree/bindings/video/bridge/ps8622.txt >> >>>> >> >>>> diff --git a/Documentation/devicetree/bindings/video/bridge/ps8622.txt b/Documentation/devicetree/bindings/video/bridge/ps8622.txt >> >>>> new file mode 100644 >> >>>> index 0000000..0ec8172 >> >>>> --- /dev/null >> >>>> +++ b/Documentation/devicetree/bindings/video/bridge/ps8622.txt >> >>>> @@ -0,0 +1,20 @@ >> >>>> +ps8622-bridge bindings >> >>>> + >> >>>> +Required properties: >> >>>> + - compatible: "parade,ps8622" or "parade,ps8625" >> >>>> + - reg: first i2c address of the bridge >> >>>> + - sleep-gpios: OF device-tree gpio specification for PD_ pin. >> >>>> + - reset-gpios: OF device-tree gpio specification for RST_ pin. >> >>>> + >> >>>> +Optional properties: >> >>>> + - lane-count: number of DP lanes to use >> >>>> + - use-external-pwm: backlight will be controlled by an external PWM >> >>> >> >>> What does this mean? That the backlight support from ps8625 is not used? >> >>> If so, maybe "disable-pwm" or something? >> >> "use-external-pwm" or "disable-bridge-pwm" would be better. >> > >> > Well, the properties are about the bridge. "use-external-pwm" means that >> > the bridge uses an external PWM, which, if I understood correctly, is >> > not what the property is about. >> > >> > "disable-bridge-pwm" is ok, but the "bridge" there is extra. The >> > properties are about the bridge, so it's implicit. >> Ok. I will use "disable-pwm". > > Why is this even necessary? According to the datasheet this device has > circuitry for backlight control. If so, I'd expect it to expose either a > backlight device or a PWM device. That way unless somebody is using the > backlight/PWM exposed by the bridge the bridge can simply disable PWM. The driver does expose a backlight device. And, the decision(whether to expose a backlight device or not) is made based on the DT flag "use-external-pwm". This was discussed before, and you suggested to use the boolean property, refer to this link: http://lists.freedesktop.org/archives/dri-devel/2014-July/065048.html Ajay -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
