On Mon, 25 Apr 2022 at 15:44, Pin-Yen Lin treapking@chromium.org wrote:

Send DPCD SET_POWER command to downstream in .atomic_disable to make the downstream monitor enter the power down mode, so the device suspend won't be affected.

Fixes: b5c84a9edcd418 ("drm/bridge: add it6505 driver") Signed-off-by: Pin-Yen Lin treapking@chromium.org

---

drivers/gpu/drm/bridge/ite-it6505.c | 29 ++++++++++++++++++----------- 1 file changed, 18 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/bridge/ite-it6505.c b/drivers/gpu/drm/bridge/ite-it6505.c index 8fed30df08b0..4b673c4792d7 100644 --- a/drivers/gpu/drm/bridge/ite-it6505.c +++ b/drivers/gpu/drm/bridge/ite-it6505.c @@ -737,8 +737,9 @@ static int it6505_drm_dp_link_probe(struct drm_dp_aux *aux, return 0; }

-static int it6505_drm_dp_link_power_up(struct drm_dp_aux *aux,

•                                  struct it6505_drm_dp_link *link)
  

+static int it6505_drm_dp_link_set_power(struct drm_dp_aux *aux,

•                                   struct it6505_drm_dp_link *link,
  

•                                   u8 mode)
  

{ u8 value; int err; @@ -752,18 +753,20 @@ static int it6505_drm_dp_link_power_up(struct drm_dp_aux *aux, return err;

    value &= ~DP_SET_POWER_MASK;

•   value |= DP_SET_POWER_D0;
  

•   value |= mode;
  
    err = drm_dp_dpcd_writeb(aux, DP_SET_POWER, value);
    if (err < 0)
            return err;
  
  

•   /*
  

•    * According to the DP 1.1 specification, a "Sink Device must exit the
  

•    * power saving state within 1 ms" (Section 2.5.3.1, Table 5-52, "Sink
  

•    * Control Field" (register 0x600).
  

•    */
  

•   usleep_range(1000, 2000);
  

•   if (mode == DP_SET_POWER_D0) {
  

•           /*
  

•            * According to the DP 1.1 specification, a "Sink Device must
  

•            * exit the power saving state within 1 ms" (Section 2.5.3.1,
  

•            * Table 5-52, "Sink Control Field" (register 0x600).
  

•            */
  

•           usleep_range(1000, 2000);
  

•   }
  
    return 0;
  

} @@ -2624,7 +2627,8 @@ static enum drm_connector_status it6505_detect(struct it6505 *it6505) if (it6505_get_sink_hpd_status(it6505)) { it6505_aux_on(it6505); it6505_drm_dp_link_probe(&it6505->aux, &it6505->link);

•           it6505_drm_dp_link_power_up(&it6505->aux, &it6505->link);
  

•           it6505_drm_dp_link_set_power(&it6505->aux, &it6505->link,
  

•                                        DP_SET_POWER_D0);
            it6505->auto_train_retry = AUTO_TRAIN_RETRY;
  
            if (it6505->dpcd[0] == 0) {
  

@@ -2960,8 +2964,11 @@ static void it6505_bridge_atomic_disable(struct drm_bridge *bridge,

    DRM_DEV_DEBUG_DRIVER(dev, "start");

•   if (it6505->powered)
  

•   if (it6505->powered) {
            it6505_video_disable(it6505);
  

•           it6505_drm_dp_link_set_power(&it6505->aux, &it6505->link,
  

•                                        DP_SET_POWER_D3);
  

•   }
  

}

static enum drm_connector_status

2.36.0.rc2.479.g8af0fa9b8e-goog

Reviewed-by: Robert Foss robert.foss@linaro.org

Applied to drm-misc-next.