<div dir="ltr"><div>> <span style="font-size:12.8px">How is backlight enabled in this case?</span></div>Using eDP BL_ENABLE pin<br></div><div class="gmail_extra"><br><div class="gmail_quote">On Sat, May 6, 2017 at 1:59 AM, Pandiyan, Dhinakaran <span dir="ltr"><<a href="mailto:dhinakaran.pandiyan@intel.com" target="_blank">dhinakaran.pandiyan@intel.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><span class="">On Wed, 2017-05-03 at 17:28 -0700, Puthikorn Voravootivat wrote:<br>
> There are some panel that<br>
> (1) does not support display backlight enable via AUX<br>
> (2) support display backlight adjustment via AUX<br>
> (3) support display backlight enable via eDP BL_ENABLE pin<br>
><br>
> The current driver required that (1) must be support to enable (2).<br>
> This patch drops that requirement.<br>
><br>
> Signed-off-by: Puthikorn Voravootivat <<a href="mailto:puthik@chromium.org">puthik@chromium.org</a>><br>
> ---<br>
>  drivers/gpu/drm/i915/intel_dp_<wbr>aux_backlight.c | 5 ++++-<br>
>  1 file changed, 4 insertions(+), 1 deletion(-)<br>
><br>
> diff --git a/drivers/gpu/drm/i915/intel_<wbr>dp_aux_backlight.c b/drivers/gpu/drm/i915/intel_<wbr>dp_aux_backlight.c<br>
> index ad8560c5f689..5b83c9737644 100644<br>
> --- a/drivers/gpu/drm/i915/intel_<wbr>dp_aux_backlight.c<br>
> +++ b/drivers/gpu/drm/i915/intel_<wbr>dp_aux_backlight.c<br>
> @@ -28,6 +28,10 @@ static void set_aux_backlight_enable(<wbr>struct intel_dp *intel_dp, bool enable)<br>
>  {<br>
>       uint8_t reg_val = 0;<br>
><br>
> +       /* Early return when display use other mechanism to enable backlight. */<br>
> +     if (!(intel_dp->edp_dpcd[1] & DP_EDP_BACKLIGHT_AUX_ENABLE_<wbr>CAP))<br>
> +             return;<br>
> +<br>
<br>
</span>How is backlight enabled in this case?<br>
<br>
-DK<br>
<div class="HOEnZb"><div class="h5"><br>
>       if (drm_dp_dpcd_readb(&intel_dp-><wbr>aux, DP_EDP_DISPLAY_CONTROL_<wbr>REGISTER,<br>
>                             &reg_val) < 0) {<br>
>               DRM_DEBUG_KMS("Failed to read DPCD register 0x%x\n",<br>
> @@ -164,7 +168,6 @@ intel_dp_aux_display_control_<wbr>capable(struct intel_connector *connector)<br>
>        * the panel can support backlight control over the aux channel<br>
>        */<br>
>       if ((intel_dp->edp_dpcd[1] & DP_EDP_TCON_BACKLIGHT_<wbr>ADJUSTMENT_CAP) &&<br>
> -         (intel_dp->edp_dpcd[1] & DP_EDP_BACKLIGHT_AUX_ENABLE_<wbr>CAP) &&<br>
>           (intel_dp->edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_<wbr>AUX_SET_CAP)) {<br>
>               DRM_DEBUG_KMS("AUX Backlight Control Supported!\n");<br>
>               return true;<br>
<br>
</div></div></blockquote></div><br></div>