diff mbox series

[v3,2/9] drm/mediatek: dp: Move AUX and panel poweron/off sequence to function

Message ID 20230404104800.301150-3-angelogioacchino.delregno@collabora.com
State New
Headers
Series MediaTek DisplayPort: support eDP and aux-bus |

Commit Message

AngeloGioacchino Del Regno April 4, 2023, 10:47 a.m. UTC 
  Everytime we run bridge detection and/or EDID read we run a poweron
and poweroff sequence for both the AUX and the panel; moreover, this
is also done when enabling the bridge in the .atomic_enable() callback.

Move this power on/off sequence to a new mtk_dp_aux_panel_poweron()
function as to commonize it.
Note that, before this commit, in mtk_dp_bridge_atomic_enable() only
the AUX was getting powered on but the panel was left powered off if
the DP cable wasn't plugged in while now we unconditionally send a D0
request and this is done for two reasons:
 - First, whether this request fails or not, it takes the same time
   and anyway the DP hardware won't produce any error (or, if it
   does, it's ignorable because it won't block further commands)
 - Second, training the link between a sleeping/standby/unpowered
   display makes little sense.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
---
 drivers/gpu/drm/mediatek/mtk_dp.c | 76 ++++++++++++-------------------
 1 file changed, 30 insertions(+), 46 deletions(-)

Comments

Chen-Yu Tsai April 6, 2023, 8:20 a.m. UTC | #1 
On Tue, Apr 4, 2023 at 6:48 PM AngeloGioacchino Del Regno
<angelogioacchino.delregno@collabora.com> wrote:
>
> Everytime we run bridge detection and/or EDID read we run a poweron
> and poweroff sequence for both the AUX and the panel; moreover, this
> is also done when enabling the bridge in the .atomic_enable() callback.
>
> Move this power on/off sequence to a new mtk_dp_aux_panel_poweron()
> function as to commonize it.
> Note that, before this commit, in mtk_dp_bridge_atomic_enable() only
> the AUX was getting powered on but the panel was left powered off if
> the DP cable wasn't plugged in while now we unconditionally send a D0
> request and this is done for two reasons:
>  - First, whether this request fails or not, it takes the same time
>    and anyway the DP hardware won't produce any error (or, if it
>    does, it's ignorable because it won't block further commands)
>  - Second, training the link between a sleeping/standby/unpowered
>    display makes little sense.
>
> Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
> ---
>  drivers/gpu/drm/mediatek/mtk_dp.c | 76 ++++++++++++-------------------
>  1 file changed, 30 insertions(+), 46 deletions(-)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_dp.c b/drivers/gpu/drm/mediatek/mtk_dp.c
> index 84f82cc68672..76ea94167531 100644
> --- a/drivers/gpu/drm/mediatek/mtk_dp.c
> +++ b/drivers/gpu/drm/mediatek/mtk_dp.c
> @@ -1253,6 +1253,29 @@ static void mtk_dp_audio_mute(struct mtk_dp *mtk_dp, bool mute)
>                            val[2], AU_TS_CFG_DP_ENC0_P0_MASK);
>  }
>
> +static void mtk_dp_aux_panel_poweron(struct mtk_dp *mtk_dp, bool pwron)
> +{
> +       if (pwron) {
> +               /* power on aux */
> +               mtk_dp_update_bits(mtk_dp, MTK_DP_TOP_PWR_STATE,
> +                                  DP_PWR_STATE_BANDGAP_TPLL_LANE,
> +                                  DP_PWR_STATE_MASK);
> +
> +               /* power on panel */
> +               drm_dp_dpcd_writeb(&mtk_dp->aux, DP_SET_POWER, DP_SET_POWER_D0);
> +               usleep_range(2000, 5000);
> +       } else {
> +               /* power off panel */
> +               drm_dp_dpcd_writeb(&mtk_dp->aux, DP_SET_POWER, DP_SET_POWER_D3);
> +               usleep_range(2000, 3000);
> +
> +               /* power off aux */
> +               mtk_dp_update_bits(mtk_dp, MTK_DP_TOP_PWR_STATE,
> +                                  DP_PWR_STATE_BANDGAP_TPLL,
> +                                  DP_PWR_STATE_MASK);
> +       }
> +}
> +
>  static void mtk_dp_power_enable(struct mtk_dp *mtk_dp)
>  {
>         mtk_dp_update_bits(mtk_dp, MTK_DP_TOP_RESET_AND_PROBE,
> @@ -1937,16 +1960,9 @@ static enum drm_connector_status mtk_dp_bdg_detect(struct drm_bridge *bridge)
>         if (!mtk_dp->train_info.cable_plugged_in)
>                 return ret;
>
> -       if (!enabled) {
> -               /* power on aux */
> -               mtk_dp_update_bits(mtk_dp, MTK_DP_TOP_PWR_STATE,
> -                                  DP_PWR_STATE_BANDGAP_TPLL_LANE,
> -                                  DP_PWR_STATE_MASK);
> +       if (!enabled)
> +               mtk_dp_aux_panel_poweron(mtk_dp, true);
>
> -               /* power on panel */
> -               drm_dp_dpcd_writeb(&mtk_dp->aux, DP_SET_POWER, DP_SET_POWER_D0);

I suspect the original code was somewhat wrong already? We shouldn't need
to pull the panel out of standby just for HPD or reading EDID.

This driver probably needs a lot more cleanup. :/

ChenYu

> -               usleep_range(2000, 5000);
> -       }
>         /*
>          * Some dongles still source HPD when they do not connect to any
>          * sink device. To avoid this, we need to read the sink count
> @@ -1958,16 +1974,8 @@ static enum drm_connector_status mtk_dp_bdg_detect(struct drm_bridge *bridge)
>         if (DP_GET_SINK_COUNT(sink_count))
>                 ret = connector_status_connected;
>
> -       if (!enabled) {
> -               /* power off panel */
> -               drm_dp_dpcd_writeb(&mtk_dp->aux, DP_SET_POWER, DP_SET_POWER_D3);
> -               usleep_range(2000, 3000);
> -
> -               /* power off aux */
> -               mtk_dp_update_bits(mtk_dp, MTK_DP_TOP_PWR_STATE,
> -                                  DP_PWR_STATE_BANDGAP_TPLL,
> -                                  DP_PWR_STATE_MASK);
> -       }
> +       if (!enabled)
> +               mtk_dp_aux_panel_poweron(mtk_dp, false);
>
>         return ret;
>  }
> @@ -1983,15 +1991,7 @@ static struct edid *mtk_dp_get_edid(struct drm_bridge *bridge,
>
>         if (!enabled) {
>                 drm_atomic_bridge_chain_pre_enable(bridge, connector->state->state);
> -
> -               /* power on aux */
> -               mtk_dp_update_bits(mtk_dp, MTK_DP_TOP_PWR_STATE,
> -                                  DP_PWR_STATE_BANDGAP_TPLL_LANE,
> -                                  DP_PWR_STATE_MASK);
> -
> -               /* power on panel */
> -               drm_dp_dpcd_writeb(&mtk_dp->aux, DP_SET_POWER, DP_SET_POWER_D0);
> -               usleep_range(2000, 5000);
> +               mtk_dp_aux_panel_poweron(mtk_dp, true);
>         }
>
>         /* eDP panels aren't removable, so we can return a cached EDID. */
> @@ -2015,15 +2015,7 @@ static struct edid *mtk_dp_get_edid(struct drm_bridge *bridge,
>         }
>
>         if (!enabled) {
> -               /* power off panel */
> -               drm_dp_dpcd_writeb(&mtk_dp->aux, DP_SET_POWER, DP_SET_POWER_D3);
> -               usleep_range(2000, 3000);
> -
> -               /* power off aux */
> -               mtk_dp_update_bits(mtk_dp, MTK_DP_TOP_PWR_STATE,
> -                                  DP_PWR_STATE_BANDGAP_TPLL,
> -                                  DP_PWR_STATE_MASK);
> -
> +               mtk_dp_aux_panel_poweron(mtk_dp, false);
>                 drm_atomic_bridge_chain_post_disable(bridge, connector->state->state);
>         }
>
> @@ -2188,15 +2180,7 @@ static void mtk_dp_bridge_atomic_enable(struct drm_bridge *bridge,
>                 return;
>         }
>
> -       /* power on aux */
> -       mtk_dp_update_bits(mtk_dp, MTK_DP_TOP_PWR_STATE,
> -                          DP_PWR_STATE_BANDGAP_TPLL_LANE,
> -                          DP_PWR_STATE_MASK);
> -
> -       if (mtk_dp->train_info.cable_plugged_in) {
> -               drm_dp_dpcd_writeb(&mtk_dp->aux, DP_SET_POWER, DP_SET_POWER_D0);
> -               usleep_range(2000, 5000);
> -       }
> +       mtk_dp_aux_panel_poweron(mtk_dp, true);
>
>         /* Training */
>         ret = mtk_dp_training(mtk_dp);
> --
> 2.40.0
>
AngeloGioacchino Del Regno April 6, 2023, 8:26 a.m. UTC | #2 
Il 06/04/23 10:20, Chen-Yu Tsai ha scritto:
> On Tue, Apr 4, 2023 at 6:48 PM AngeloGioacchino Del Regno
> <angelogioacchino.delregno@collabora.com> wrote:
>>
>> Everytime we run bridge detection and/or EDID read we run a poweron
>> and poweroff sequence for both the AUX and the panel; moreover, this
>> is also done when enabling the bridge in the .atomic_enable() callback.
>>
>> Move this power on/off sequence to a new mtk_dp_aux_panel_poweron()
>> function as to commonize it.
>> Note that, before this commit, in mtk_dp_bridge_atomic_enable() only
>> the AUX was getting powered on but the panel was left powered off if
>> the DP cable wasn't plugged in while now we unconditionally send a D0
>> request and this is done for two reasons:
>>   - First, whether this request fails or not, it takes the same time
>>     and anyway the DP hardware won't produce any error (or, if it
>>     does, it's ignorable because it won't block further commands)
>>   - Second, training the link between a sleeping/standby/unpowered
>>     display makes little sense.
>>
>> Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
>> ---
>>   drivers/gpu/drm/mediatek/mtk_dp.c | 76 ++++++++++++-------------------
>>   1 file changed, 30 insertions(+), 46 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/mediatek/mtk_dp.c b/drivers/gpu/drm/mediatek/mtk_dp.c
>> index 84f82cc68672..76ea94167531 100644
>> --- a/drivers/gpu/drm/mediatek/mtk_dp.c
>> +++ b/drivers/gpu/drm/mediatek/mtk_dp.c
>> @@ -1253,6 +1253,29 @@ static void mtk_dp_audio_mute(struct mtk_dp *mtk_dp, bool mute)
>>                             val[2], AU_TS_CFG_DP_ENC0_P0_MASK);
>>   }
>>
>> +static void mtk_dp_aux_panel_poweron(struct mtk_dp *mtk_dp, bool pwron)
>> +{
>> +       if (pwron) {
>> +               /* power on aux */
>> +               mtk_dp_update_bits(mtk_dp, MTK_DP_TOP_PWR_STATE,
>> +                                  DP_PWR_STATE_BANDGAP_TPLL_LANE,
>> +                                  DP_PWR_STATE_MASK);
>> +
>> +               /* power on panel */
>> +               drm_dp_dpcd_writeb(&mtk_dp->aux, DP_SET_POWER, DP_SET_POWER_D0);
>> +               usleep_range(2000, 5000);
>> +       } else {
>> +               /* power off panel */
>> +               drm_dp_dpcd_writeb(&mtk_dp->aux, DP_SET_POWER, DP_SET_POWER_D3);
>> +               usleep_range(2000, 3000);
>> +
>> +               /* power off aux */
>> +               mtk_dp_update_bits(mtk_dp, MTK_DP_TOP_PWR_STATE,
>> +                                  DP_PWR_STATE_BANDGAP_TPLL,
>> +                                  DP_PWR_STATE_MASK);
>> +       }
>> +}
>> +
>>   static void mtk_dp_power_enable(struct mtk_dp *mtk_dp)
>>   {
>>          mtk_dp_update_bits(mtk_dp, MTK_DP_TOP_RESET_AND_PROBE,
>> @@ -1937,16 +1960,9 @@ static enum drm_connector_status mtk_dp_bdg_detect(struct drm_bridge *bridge)
>>          if (!mtk_dp->train_info.cable_plugged_in)
>>                  return ret;
>>
>> -       if (!enabled) {
>> -               /* power on aux */
>> -               mtk_dp_update_bits(mtk_dp, MTK_DP_TOP_PWR_STATE,
>> -                                  DP_PWR_STATE_BANDGAP_TPLL_LANE,
>> -                                  DP_PWR_STATE_MASK);
>> +       if (!enabled)
>> +               mtk_dp_aux_panel_poweron(mtk_dp, true);
>>
>> -               /* power on panel */
>> -               drm_dp_dpcd_writeb(&mtk_dp->aux, DP_SET_POWER, DP_SET_POWER_D0);
> 
> I suspect the original code was somewhat wrong already? We shouldn't need
> to pull the panel out of standby just for HPD or reading EDID.
> 
> This driver probably needs a lot more cleanup. :/
> 

I believe the same... but I wanted to play safe, as I don't know if there's any
panel in particular that requires such quirk...

Angelo
diff mbox series

Patch

diff --git a/drivers/gpu/drm/mediatek/mtk_dp.c b/drivers/gpu/drm/mediatek/mtk_dp.c
index 84f82cc68672..76ea94167531 100644
--- a/drivers/gpu/drm/mediatek/mtk_dp.c
+++ b/drivers/gpu/drm/mediatek/mtk_dp.c
@@ -1253,6 +1253,29 @@  static void mtk_dp_audio_mute(struct mtk_dp *mtk_dp, bool mute)
 			   val[2], AU_TS_CFG_DP_ENC0_P0_MASK);
 }
 
+static void mtk_dp_aux_panel_poweron(struct mtk_dp *mtk_dp, bool pwron)
+{
+	if (pwron) {
+		/* power on aux */
+		mtk_dp_update_bits(mtk_dp, MTK_DP_TOP_PWR_STATE,
+				   DP_PWR_STATE_BANDGAP_TPLL_LANE,
+				   DP_PWR_STATE_MASK);
+
+		/* power on panel */
+		drm_dp_dpcd_writeb(&mtk_dp->aux, DP_SET_POWER, DP_SET_POWER_D0);
+		usleep_range(2000, 5000);
+	} else {
+		/* power off panel */
+		drm_dp_dpcd_writeb(&mtk_dp->aux, DP_SET_POWER, DP_SET_POWER_D3);
+		usleep_range(2000, 3000);
+
+		/* power off aux */
+		mtk_dp_update_bits(mtk_dp, MTK_DP_TOP_PWR_STATE,
+				   DP_PWR_STATE_BANDGAP_TPLL,
+				   DP_PWR_STATE_MASK);
+	}
+}
+
 static void mtk_dp_power_enable(struct mtk_dp *mtk_dp)
 {
 	mtk_dp_update_bits(mtk_dp, MTK_DP_TOP_RESET_AND_PROBE,
@@ -1937,16 +1960,9 @@  static enum drm_connector_status mtk_dp_bdg_detect(struct drm_bridge *bridge)
 	if (!mtk_dp->train_info.cable_plugged_in)
 		return ret;
 
-	if (!enabled) {
-		/* power on aux */
-		mtk_dp_update_bits(mtk_dp, MTK_DP_TOP_PWR_STATE,
-				   DP_PWR_STATE_BANDGAP_TPLL_LANE,
-				   DP_PWR_STATE_MASK);
+	if (!enabled)
+		mtk_dp_aux_panel_poweron(mtk_dp, true);
 
-		/* power on panel */
-		drm_dp_dpcd_writeb(&mtk_dp->aux, DP_SET_POWER, DP_SET_POWER_D0);
-		usleep_range(2000, 5000);
-	}
 	/*
 	 * Some dongles still source HPD when they do not connect to any
 	 * sink device. To avoid this, we need to read the sink count
@@ -1958,16 +1974,8 @@  static enum drm_connector_status mtk_dp_bdg_detect(struct drm_bridge *bridge)
 	if (DP_GET_SINK_COUNT(sink_count))
 		ret = connector_status_connected;
 
-	if (!enabled) {
-		/* power off panel */
-		drm_dp_dpcd_writeb(&mtk_dp->aux, DP_SET_POWER, DP_SET_POWER_D3);
-		usleep_range(2000, 3000);
-
-		/* power off aux */
-		mtk_dp_update_bits(mtk_dp, MTK_DP_TOP_PWR_STATE,
-				   DP_PWR_STATE_BANDGAP_TPLL,
-				   DP_PWR_STATE_MASK);
-	}
+	if (!enabled)
+		mtk_dp_aux_panel_poweron(mtk_dp, false);
 
 	return ret;
 }
@@ -1983,15 +1991,7 @@  static struct edid *mtk_dp_get_edid(struct drm_bridge *bridge,
 
 	if (!enabled) {
 		drm_atomic_bridge_chain_pre_enable(bridge, connector->state->state);
-
-		/* power on aux */
-		mtk_dp_update_bits(mtk_dp, MTK_DP_TOP_PWR_STATE,
-				   DP_PWR_STATE_BANDGAP_TPLL_LANE,
-				   DP_PWR_STATE_MASK);
-
-		/* power on panel */
-		drm_dp_dpcd_writeb(&mtk_dp->aux, DP_SET_POWER, DP_SET_POWER_D0);
-		usleep_range(2000, 5000);
+		mtk_dp_aux_panel_poweron(mtk_dp, true);
 	}
 
 	/* eDP panels aren't removable, so we can return a cached EDID. */
@@ -2015,15 +2015,7 @@  static struct edid *mtk_dp_get_edid(struct drm_bridge *bridge,
 	}
 
 	if (!enabled) {
-		/* power off panel */
-		drm_dp_dpcd_writeb(&mtk_dp->aux, DP_SET_POWER, DP_SET_POWER_D3);
-		usleep_range(2000, 3000);
-
-		/* power off aux */
-		mtk_dp_update_bits(mtk_dp, MTK_DP_TOP_PWR_STATE,
-				   DP_PWR_STATE_BANDGAP_TPLL,
-				   DP_PWR_STATE_MASK);
-
+		mtk_dp_aux_panel_poweron(mtk_dp, false);
 		drm_atomic_bridge_chain_post_disable(bridge, connector->state->state);
 	}
 
@@ -2188,15 +2180,7 @@  static void mtk_dp_bridge_atomic_enable(struct drm_bridge *bridge,
 		return;
 	}
 
-	/* power on aux */
-	mtk_dp_update_bits(mtk_dp, MTK_DP_TOP_PWR_STATE,
-			   DP_PWR_STATE_BANDGAP_TPLL_LANE,
-			   DP_PWR_STATE_MASK);
-
-	if (mtk_dp->train_info.cable_plugged_in) {
-		drm_dp_dpcd_writeb(&mtk_dp->aux, DP_SET_POWER, DP_SET_POWER_D0);
-		usleep_range(2000, 5000);
-	}
+	mtk_dp_aux_panel_poweron(mtk_dp, true);
 
 	/* Training */
 	ret = mtk_dp_training(mtk_dp);