Commit:     e593f070b40887dc0415646a4c0720eb8630c722
Parent:     2868f89fc43d16441a90714d4676089bdfc4255a
Author:     Anti Sullin <[EMAIL PROTECTED]>
AuthorDate: Wed Nov 28 16:21:40 2007 -0800
Committer:  Linus Torvalds <[EMAIL PROTECTED]>
CommitDate: Thu Nov 29 09:24:53 2007 -0800

    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 <[EMAIL PROTECTED]>
    Signed-off-by: Andrew Victor <[EMAIL PROTECTED]>
    Signed-off-by: Nicolas Ferre <[EMAIL PROTECTED]>
    Acked-by: Haavard Skinnemoen <[EMAIL PROTECTED]>
    Cc: "Antonino A. Daplas" <[EMAIL PROTECTED]>
    Signed-off-by: Andrew Morton <[EMAIL PROTECTED]>
    Signed-off-by: Linus Torvalds <[EMAIL PROTECTED]>
 drivers/video/atmel_lcdfb.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/drivers/video/atmel_lcdfb.c b/drivers/video/atmel_lcdfb.c
index 235b618..11a3a22 100644
--- a/drivers/video/atmel_lcdfb.c
+++ b/drivers/video/atmel_lcdfb.c
@@ -268,6 +268,10 @@ static int atmel_lcdfb_set_par(struct fb_info *info)
        /* Turn off the LCD controller and the DMA controller */
        lcdc_writel(sinfo, ATMEL_LCDC_PWRCON, sinfo->guard_time << 
+       /* Wait for the LCDC core to become idle */
+       while (lcdc_readl(sinfo, ATMEL_LCDC_PWRCON) & ATMEL_LCDC_BUSY)
+               msleep(10);
        lcdc_writel(sinfo, ATMEL_LCDC_DMACON, 0);
        if (info->var.bits_per_pixel == 1)
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