Re: [PATCH] drm/msm/dp: employ bridge mechanism for display enable and disable

Quoting Kuogee Hsieh (2021-11-02 15:13:44)

Current display mode_set, enable and disable functions are implemented as function called directly from drm encoder. This patch have display mode_set, enable and disable be implemented as callback function of drm bridge.

Why is it important? Please add those details here.

Signed-off-by: Kuogee Hsieh quic_khsieh@quicinc.com

drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 21 ------ drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c | 8 ++ drivers/gpu/drm/msm/dp/dp_display.c | 26 +++---- drivers/gpu/drm/msm/dp/dp_display.h | 8 ++ drivers/gpu/drm/msm/dp/dp_drm.c | 113 ++++++++++++++++++++++++++++ drivers/gpu/drm/msm/msm_drv.h | 29 ++----- 6 files changed, 147 insertions(+), 58 deletions(-)

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c index 27d98b5..3bbd09c 100644 --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c @@ -557,6 +557,14 @@ static int _dpu_kms_initialize_displayport(struct drm_device *dev, encoder->base.id, rc); return rc; }

•           rc = msm_dp_bridge_init(priv->dp[i], dev, encoder);
  

Use tabs?

•            if (rc) {
  

•                   DPU_ERROR("failed to setup DPU bridge %d: rc:%d\n",
  

•                             encoder->base.id, rc);
  

•                   return rc;
  

•            }
  

•   }
  
    return rc;
  

diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c index e41dd40..317f963 100644 --- a/drivers/gpu/drm/msm/dp/dp_display.c +++ b/drivers/gpu/drm/msm/dp/dp_display.c @@ -569,8 +569,8 @@ static int dp_hpd_plug_handle(struct dp_display_private *dp, u32 data) return 0; };

-static int dp_display_enable(struct dp_display_private *dp, u32 data); -static int dp_display_disable(struct dp_display_private *dp, u32 data); +static int __dp_display_enable(struct dp_display_private *dp, u32 data); +static int __dp_display_disable(struct dp_display_private *dp, u32 data);

static int dp_connect_pending_timeout(struct dp_display_private *dp, u32 data) { @@ -855,7 +855,7 @@ static int dp_display_prepare(struct msm_dp *dp_display) return 0; }

-static int dp_display_enable(struct dp_display_private *dp, u32 data) +static int __dp_display_enable(struct dp_display_private *dp, u32 data) { int rc = 0;

@@ -898,7 +898,7 @@ static int dp_display_post_enable(struct msm_dp *dp_display) return 0; }

-static int dp_display_disable(struct dp_display_private *dp, u32 data) +static int __dp_display_disable(struct dp_display_private *dp, u32 data) { struct msm_dp *dp_display = &dp->dp_display;

@@ -1533,7 +1533,7 @@ int msm_dp_modeset_init(struct msm_dp *dp_display, struct drm_device *dev, return 0; }

-int msm_dp_display_enable(struct msm_dp *dp, struct drm_encoder *encoder) +int dp_display_enable(struct msm_dp *dp, struct drm_encoder *encoder) { int rc = 0; struct dp_display_private *dp_display; @@ -1569,12 +1569,12 @@ int msm_dp_display_enable(struct msm_dp *dp, struct drm_encoder *encoder) if (state == ST_DISPLAY_OFF) dp_display_host_init(dp_display, true);

•   dp_display_enable(dp_display, 0);
  

•   __dp_display_enable(dp_display, 0);
  
    rc = dp_display_post_enable(dp);
    if (rc) {
            DRM_ERROR("DP display post enable failed, rc=%d\n", rc);
  

•           dp_display_disable(dp_display, 0);
  

•           __dp_display_disable(dp_display, 0);
            dp_display_unprepare(dp);
    }
  
  

@@ -1590,7 +1590,7 @@ int msm_dp_display_enable(struct msm_dp *dp, struct drm_encoder *encoder) return rc; }

-int msm_dp_display_pre_disable(struct msm_dp *dp, struct drm_encoder *encoder) +int dp_display_pre_disable(struct msm_dp *dp, struct drm_encoder *encoder) { struct dp_display_private *dp_display;

@@ -1601,7 +1601,7 @@ int msm_dp_display_pre_disable(struct msm_dp *dp, struct drm_encoder *encoder) return 0; }

-int msm_dp_display_disable(struct msm_dp *dp, struct drm_encoder *encoder) +int dp_display_disable(struct msm_dp *dp, struct drm_encoder *encoder) { int rc = 0; u32 state; @@ -1614,7 +1614,7 @@ int msm_dp_display_disable(struct msm_dp *dp, struct drm_encoder *encoder) /* stop sentinel checking */ dp_del_event(dp_display, EV_DISCONNECT_PENDING_TIMEOUT);

•   dp_display_disable(dp_display, 0);
  

•   __dp_display_disable(dp_display, 0);
  
    rc = dp_display_unprepare(dp);
    if (rc)
  

@@ -1632,9 +1632,9 @@ int msm_dp_display_disable(struct msm_dp *dp, struct drm_encoder *encoder) return rc; }

-void msm_dp_display_mode_set(struct msm_dp *dp, struct drm_encoder *encoder,

•                           struct drm_display_mode *mode,
  

•                           struct drm_display_mode *adjusted_mode)
  

+void dp_display_mode_set(struct msm_dp *dp, struct drm_encoder *encoder,

I enjoyed the msm_dp prefix before, please leave this alone. It will make the patch much smaller too.

•                           const struct drm_display_mode *mode,
  

•                           const struct drm_display_mode *adjusted_mode)
  

{ struct dp_display_private *dp_display;

diff --git a/drivers/gpu/drm/msm/dp/dp_display.h b/drivers/gpu/drm/msm/dp/dp_display.h index 76f45f9..4fb6ada 100644 --- a/drivers/gpu/drm/msm/dp/dp_display.h +++ b/drivers/gpu/drm/msm/dp/dp_display.h @@ -13,6 +13,7 @@ struct msm_dp { struct drm_device *drm_dev; struct device *codec_dev;

•   struct drm_bridge *bridge;
    struct drm_connector *connector;
    struct drm_encoder *encoder;
    struct drm_panel *drm_panel;
  

@@ -40,4 +41,11 @@ int dp_display_get_test_bpp(struct msm_dp *dp_display); void dp_display_signal_audio_start(struct msm_dp *dp_display); void dp_display_signal_audio_complete(struct msm_dp *dp_display);

+int dp_display_enable(struct msm_dp *dp, struct drm_encoder *encoder); +int dp_display_disable(struct msm_dp *dp, struct drm_encoder *encoder); +int dp_display_pre_disable(struct msm_dp *dp, struct drm_encoder *encoder); +void dp_display_mode_set(struct msm_dp *dp, struct drm_encoder *encoder,

•                           const struct drm_display_mode *mode,
  

•                           const struct drm_display_mode *adjusted_mode);
  

#endif /* _DP_DISPLAY_H_ */ diff --git a/drivers/gpu/drm/msm/dp/dp_drm.c b/drivers/gpu/drm/msm/dp/dp_drm.c index f33e315..812a091 100644 --- a/drivers/gpu/drm/msm/dp/dp_drm.c +++ b/drivers/gpu/drm/msm/dp/dp_drm.c @@ -3,14 +3,25 @@

• Copyright (c) 2017-2020, The Linux Foundation. All rights reserved.

*/

+#include <linux/platform_device.h>

Why is this include necessary?

#include <drm/drm_atomic_helper.h> #include <drm/drm_atomic.h> +#include <drm/drm_bridge.h> #include <drm/drm_crtc.h>

#include "msm_drv.h" #include "msm_kms.h" #include "dp_drm.h"

+struct dp_bridge {

msm_dp_bridge?

•    struct drm_bridge bridge;
  

•    struct msm_dp *dp_display;
  

+};

+#define to_dp_display(x) container_of((x), struct dp_bridge, bridge)

struct dp_connector { struct drm_connector base; struct msm_dp *dp_display; @@ -162,3 +173,105 @@ struct drm_connector *dp_drm_connector_init(struct msm_dp *dp_display)

    return connector;

}

+static int dp_bridge_attach(struct drm_bridge *dp_bridge,

•                            enum drm_bridge_attach_flags flags)
  

+{

•   return 0;
  

+}

+static bool dp_bridge_mode_fixup(struct drm_bridge *drm_bridge,

•                              const struct drm_display_mode *mode,
  

•                              struct drm_display_mode *adjusted_mode)
  

+{

•   return true;
  

+}

Do we need these largely empty functions?

+static void dp_bridge_mode_set(struct drm_bridge *drm_bridge,

•                            const struct drm_display_mode *mode,
  

•                            const struct drm_display_mode *adjusted_mode)
  

+{

•   struct dp_bridge *dp_bridge = to_dp_display(drm_bridge);
  

•   struct msm_dp *dp_display = dp_bridge->dp_display;
  

•   dp_display_mode_set(dp_display, drm_bridge->encoder, mode, adjusted_mode);
  

+}

+static void dp_bridge_pre_enable(struct drm_bridge *drm_bridge) +{

+}

Do we need this empty function?

+static void dp_bridge_enable(struct drm_bridge *drm_bridge) +{

•   struct dp_bridge *dp_bridge = to_dp_display(drm_bridge);
  

•   struct msm_dp *dp_display = dp_bridge->dp_display;
  

•   dp_display_enable(dp_display, drm_bridge->encoder);
  

+}

+static void dp_bridge_disable(struct drm_bridge *drm_bridge) +{

•   struct dp_bridge *dp_bridge = to_dp_display(drm_bridge);
  

•   struct msm_dp *dp_display = dp_bridge->dp_display;
  

•   dp_display_pre_disable(dp_display, drm_bridge->encoder);
  

+}

+static void dp_bridge_post_disable(struct drm_bridge *drm_bridge) +{

•   struct dp_bridge *dp_bridge = to_dp_display(drm_bridge);
  

•   struct msm_dp *dp_display = dp_bridge->dp_display;
  

•   dp_display_disable(dp_display, drm_bridge->encoder);
  

+}

+static const struct drm_bridge_funcs dp_bridge_ops = {

•    .attach       = dp_bridge_attach,
  

•    .mode_fixup   = dp_bridge_mode_fixup,
  

•    .pre_enable   = dp_bridge_pre_enable,
  

•    .enable       = dp_bridge_enable,
  

•    .disable      = dp_bridge_disable,
  

•    .post_disable = dp_bridge_post_disable,
  

•    .mode_set     = dp_bridge_mode_set,
  

+};

+int msm_dp_bridge_init(struct msm_dp *dp_display, struct drm_device *dev,

•                   struct drm_encoder *encoder)
  

+{

•   int rc = 0;
  

Use tabs?

•    struct msm_drm_private *priv = NULL;
  

Please drop initialization of rc and priv.

•    struct dp_bridge *dp_bridge;
  

•   struct drm_bridge *bridge;
  

Use tabs?

•    dp_bridge = kzalloc(sizeof(*dp_bridge), GFP_KERNEL);
  

•    if (!dp_bridge) {
  

•            rc = -ENOMEM;
  

•            goto error;
  

return -ENOMEM;

•    }
  

•    dp_bridge->dp_display = dp_display;
  

•   bridge = &dp_bridge->bridge;
  

Use tabs?

•    bridge->funcs = &dp_bridge_ops;
  

•    bridge->encoder = encoder;
  

•    rc = drm_bridge_attach(encoder, bridge, NULL, 0);
  

We need DRM_BRIDGE_ATTACH_NO_CONNECTOR flag set as this driver makes a connector, right?

•    if (rc) {
  

•            DRM_ERROR("failed to attach bridge, rc=%d\n", rc);
  

•            goto error_free_bridge;
  

•    }
  

•    priv = dev->dev_private;
  

•   priv->bridges[priv->num_bridges++] = bridge;
  

•   dp_display->bridge = bridge;
  

More weird tabs.

•    return 0;
  

+error_free_bridge:

•    kfree(bridge);
  

+error:

•    return rc;
  

+}