Hi Laurent,
sorry, I might be confused but,
On Tue, Sep 04, 2018 at 03:10:15PM +0300, Laurent Pinchart wrote:
> The THC63LVD1024 is restricted to a pixel clock frequency in the range
> of 8 to 135 MHz. Implement the bridge .mode_valid() operation
> accordingly.
>
> Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
> ---
> drivers/gpu/drm/bridge/thc63lvd1024.c | 18 ++++++++++++++++++
> 1 file changed, 18 insertions(+)
>
> diff --git a/drivers/gpu/drm/bridge/thc63lvd1024.c b/drivers/gpu/drm/bridge/thc63lvd1024.c
> index c8b9edd5a7f4..63609ba16b6d 100644
> --- a/drivers/gpu/drm/bridge/thc63lvd1024.c
> +++ b/drivers/gpu/drm/bridge/thc63lvd1024.c
> @@ -45,6 +45,23 @@ static int thc63_attach(struct drm_bridge *bridge)
> return drm_bridge_attach(bridge->encoder, thc63->next, bridge);
> }
>
> +static enum drm_mode_status thc63_mode_valid(struct drm_bridge *bridge,
> + const struct drm_display_mode *mode)
> +{
> + /*
> + * The THC63LVD0124 clock frequency range is 8 to 135 MHz in single-in,
> + * single-out mode. Note that the limits depends on the mode and will
> + * need to be adjusted accordingly.
> + */
> + if (mode->clock < 8000)
> + return MODE_CLOCK_LOW;
> +
> + if (mode->clock > 135000)
> + return MODE_CLOCK_HIGH;
> +
> + return MODE_OK;
> +}
> +
Are we talking about the CLKOUT frequency? Because that's the one I
see depending on the dual/single output mode, and I assume we're
checking for the mode->clock of the DRM mode to be applied to the
connector (which receives an RGB stream from this bridge).
In case we're talking about CLKOUT, I read
"Dual LVDS port IN/Dual TTL port Out Mode:
8 - 135MHz(CLKOUT)
Dual LVDS port IN/Single TTL port Out Mode:
40 - 150MHz(CLKOUT)"
If we're talking about the PLL input clock (RCLK) then used to
generate CLKOUT it's indeed defined in the 8-135Mhz range, but
I don't see mention on it depending on the mode.
> static void thc63_enable(struct drm_bridge *bridge)
> {
> struct thc63_dev *thc63 = to_thc63(bridge);
> @@ -77,6 +94,7 @@ static void thc63_disable(struct drm_bridge *bridge)
>
> static const struct drm_bridge_funcs thc63_bridge_func = {
> .attach = thc63_attach,
> + .mode_valid = thc63_mode_valid,
> .enable = thc63_enable,
> .disable = thc63_disable,
> };
> --
> Regards,
>
> Laurent Pinchart
>
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