video: ipu_disp: Fix clock polarity logic

Currently the HDMI splash screen image quality on mx6solo does not show a
very stable image.

By comparing the IPU driver from U-boot with the one from FSL 4.1.0 BSP,
we can see that there is an inverted logic for setting the DI_GEN_POL_CLK bit.

>From FSL BSP [1] we have:

	if (!sig.clk_pol)
		di_gen |= DI_GEN_POLARITY_DISP_CLK;

Applying the same logic into U-boot fixes the HDMI image stability.

[1] git.freescale.com/git/cgit.cgi/imx/linux-2.6-imx.git/tree/drivers/mxc/ipu3/ipu_disp.c?h=imx_3.0.35_4.1.0

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Tested-by: Eric Nelson <eric.nelson@boundarydevices.com>
Acked-by: Eric Nelson <eric.nelson@boundarydevices.com>
Acked-by: Stefano Babic <sbabic@denx.de>

diff --git a/drivers/video/ipu_disp.c b/drivers/video/ipu_disp.c
index 2e913561d08e9ba2eb528dd5ffb80caa71794362..22ac1429ba498fe10c3171f594593d722251a816 100644 (file)
--- a/drivers/video/ipu_disp.c
+++ b/drivers/video/ipu_disp.c
@@ -1178,7 +1178,7 @@ int32_t ipu_init_sync_panel(int disp, uint32_t pixel_clk,
                if (sig.Vsync_pol)
                        di_gen |= DI_GEN_POLARITY_3;
 
-               if (sig.clk_pol)
+               if (!sig.clk_pol)
                        di_gen |= DI_GEN_POL_CLK;
 
        }