atmel_lcdfb: LCDC startup fix
This patch adds an additional loop, that delays turning off the DMA until the LCDC core has been turned off. This prevents the picture to be shifted some random length when the kernel re-initializes the LCDC. Without this patch, the LCDC keeps running for some small time after the PWRCON:LCD_PWR has been cleared ; the FIFO suffers an underrun and on re-starting the LCDC the FIFO data stays shifted. This behavior has been seen and fixed on AT91SAM9261-EK and two custom AT91SAM9261 boards, all of them having different LCD panels. Thanks a lot to Anti Sullin for submitting this patch (long time ago). Signed-off-by: Anti Sullin <anti.sullin@artecdesign.ee> Signed-off-by: Andrew Victor <andrew@sanpeople.com> Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com> Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Cc: "Antonino A. Daplas" <adaplas@pol.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Showing
Please register or sign in to comment