On 2013-02-13 17:28, Tomi Valkeinen wrote: > On 2013-02-13 17:16, Igor Grinberg wrote: >> Hi Archit, >> >> On 02/13/13 16:21, Archit Taneja wrote: >>> The cm-t35 board file currently requests gpios required to configure the tdo35s >>> panel, and provides platform_enable/disable callbacks to configure them. >>> >>> These tasks have been moved to the generic dpi panel driver itself and shouldn't >>> be done in the board files. >>> >>> Remove the gpio requests and the platform callbacks from the board file. >>> Add the gpio information to generic dpi panel's platform data so that it's >>> passed to the panel driver. >>> >>> Note: In cm_t35_init_display(), the gpios were disabled, and the LCD_EN gpio was >>> enabled after a 50 millisecond delay. This code has been removed and is not >>> taken care of in the generic panel driver. The impact of this needs to be >>> tested. The panel's gpios are also not exported any more. Hence, they can't be >>> accessed via sysfs interface. >> >> Indeed, there is an impact - the LCD no longer works. >> The reason for the LCD_EN gpio being pushed high after the 50ms delay, >> is to get the LCD out of reset, so the SPI transaction will succeed >> and initialize the LCD. >> Now, when you remove the gpio handling for the LCD_EN pin, >> the LCD no longer works. > > So between what is the sleep done? It's not clear from the code. LCD_EN > needs to be 0 for 50ms, or...? > > If the panel requires specific reset handling, does it work right even > currently when the panel is turned off and later turned on? The msleep > is only used at boot time. Okay, so I just realized there's an spi backlight driver used here, and that backlight driver is actually handling the SPI transactions with the panel, instead of the panel driver. So this looks quite messed up. For a quick solution, can we just set the LCD_EN at boot time (with the msleep), and not touch it after that? Tomi
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