omap: overo: Disable pull-ups on camera PCLK, HS and VS signals

The level shifters used on the Caspa camera module have a 4k output
impedance. Combined with the 100uA pull-up resistors in the OMAP3,
this raises the ground level to 400mV. Adding crosstalk between the
pixel clock and the HS/VS signals on the flat cable (a ground line in
between would have been nice), logic 0 levels can raise up to 650mV.
This exceeds the camera input pins VIL maximum voltage.  This change
suggested-by Laurent Pinchart

Signed-off-by: Steve Sakoman <steve@sakoman.com>
Signed-off-by: Sandeep Paulraj <s-paulraj@ti.com>

diff --git a/board/overo/overo.h b/board/overo/overo.h
index 42ef1b1..915f15b 100644 (file)
--- a/board/overo/overo.h
+++ b/board/overo/overo.h
@@ -160,10 +160,10 @@ const omap3_sysinfo sysinfo = {
        MUX_VAL(CP(DSS_DATA22),         (IDIS | PTD | DIS | M0)) /*DSS_DATA22*/\
        MUX_VAL(CP(DSS_DATA23),         (IDIS | PTD | DIS | M0)) /*DSS_DATA23*/\
  /*CAMERA*/\
-       MUX_VAL(CP(CAM_HS),             (IEN  | PTU | EN  | M0)) /*CAM_HS */\
-       MUX_VAL(CP(CAM_VS),             (IEN  | PTU | EN  | M0)) /*CAM_VS */\
+       MUX_VAL(CP(CAM_HS),             (IEN  | PTU | DIS | M0)) /*CAM_HS */\
+       MUX_VAL(CP(CAM_VS),             (IEN  | PTU | DIS | M0)) /*CAM_VS */\
        MUX_VAL(CP(CAM_XCLKA),          (IDIS | PTD | DIS | M0)) /*CAM_XCLKA*/\
-       MUX_VAL(CP(CAM_PCLK),           (IEN  | PTU | EN  | M0)) /*CAM_PCLK*/\
+       MUX_VAL(CP(CAM_PCLK),           (IEN  | PTU | DIS | M0)) /*CAM_PCLK*/\
        MUX_VAL(CP(CAM_FLD),            (IDIS | PTD | DIS | M4)) /*CAM_FLD*/\
        MUX_VAL(CP(CAM_D0),             (IEN  | PTD | DIS | M0)) /*CAM_D0*/\
        MUX_VAL(CP(CAM_D1),             (IEN  | PTD | DIS | M0)) /*CAM_D1*/\