On Thu, Apr 04, 2013 at 11:19:44, Nori, Sekhar wrote: > On 4/4/2013 10:09 AM, Philip, Avinash wrote: > > On Tue, Apr 02, 2013 at 14:05:09, Nori, Sekhar wrote: > >> On 3/25/2013 1:19 PM, Philip Avinash wrote: > >>> Add platform support for EHRPWM and ECAP by providing clock nodes and > >>> device tree nodes. > >>> This series depends on [1] and [2] and is available for testing at [3]. > >>> Tested for back light support in da850 EVM with EHRPWM PWM device. > >>> > >>> [1] > >>> http://gitorious.org/linux-davinci/linux-davinci/trees/davinci-for-v3.9/dt-2 > >>> [2] https://gitorious.org/linux-pwm/linux-pwm/trees/for-next > >>> [3] > >>> https://github.com/avinashphilip/am335x_linux/tree/davinci-for-v3.9_soc_pwm > >>> > >>> Note: > >>> DT support for EHRPWM backlight has not been added in da850-evm.dts as > >>> there is > >>> conflicting pin-mux requirement with SPI flash. > >> > >> Can you check if this is really true even in newer boards (have a look > >> at the latest schematics)? I remember this used to be a problem in very > >> early versions but was fixed later. > > > > On looking schematics, panel has three power controls LCD_BACKLIGHT_PWR, > > LCD_PANEL_PWR, > > LCD_PWM0. On latest schematic, LCD_PWM0 is connected to ECAP instance 2. So > > backlight > > can control through ECAP2 (not conflicting with SPI1 cs0). Still for > > controlling > > backlight, require support for LCD_BACKLIGHT_PWR & LCD_PANEL_PWR. These > > signals > > By controlling above you mean "switching on/off"? Otherwise this seems > to be contradicting the statement just before.
Yes these lines should be switching on/off. > > > to be controlled by GPIO 2[8] & GPIO 2[15]. In release platform callbacks > > used > > to control GPIO functionality. But with DT support, I have to check how > > platform > > callbacks can be used. > > Platform callbacks are not possible with DT. Ok. > You can look at what freescale mxsfb.c does. Look for panel-enable-gpios DT > binding. I will use GPIO pin configuration info from DT nodes. From probe GPIO pin make active and in remove disable GPIO pin. Thanks Avinash > > Thanks, > Sekhar >