Re: [PATCH v10 1/4] gpu: drm: separate panel orientation property creating and value setting

Hi,

On 5/30/22 10:57, Hans de Goede wrote:

Hi,

On 5/30/22 10:19, Hsin-Yi Wang wrote:

...

drm_dev_register() sets connector->registration_state to DRM_CONNECTOR_REGISTERED and dev->registered to true. If drm_connector_set_panel_orientation() is first called after drm_dev_register(), it will fail several checks and results in following warning.

Add a function to create panel orientation property and set default value to UNKNOWN, so drivers can call this function to init the property earlier , and let the panel set the real value later.

[ 4.480976] ------------[ cut here ]------------ [ 4.485603] WARNING: CPU: 5 PID: 369 at drivers/gpu/drm/drm_mode_object.c:45 __drm_mode_object_add+0xb4/0xbc

<snip> [ 4.609772] Call trace: [ 4.612208] __drm_mode_object_add+0xb4/0xbc [ 4.616466] drm_mode_object_add+0x20/0x2c [ 4.620552] drm_property_create+0xdc/0x174 [ 4.624723] drm_property_create_enum+0x34/0x98 [ 4.629241] drm_connector_set_panel_orientation+0x64/0xa0 [ 4.634716] boe_panel_get_modes+0x88/0xd8 [ 4.638802] drm_panel_get_modes+0x2c/0x48 [ 4.642887] panel_bridge_get_modes+0x1c/0x28 [ 4.647233] drm_bridge_connector_get_modes+0xa0/0xd4 [ 4.652273] drm_helper_probe_single_connector_modes+0x218/0x700 [ 4.658266] drm_mode_getconnector+0x1b4/0x45c [ 4.662699] drm_ioctl_kernel+0xac/0x128 [ 4.666611] drm_ioctl+0x268/0x410 [ 4.670002] drm_compat_ioctl+0xdc/0xf0 [ 4.673829] __arm64_compat_sys_ioctl+0xc8/0x100 [ 4.678436] el0_svc_common+0xf4/0x1c0 [ 4.682174] do_el0_svc_compat+0x28/0x3c [ 4.686088] el0_svc_compat+0x10/0x1c [ 4.689738] el0_sync_compat_handler+0xa8/0xcc [ 4.694171] el0_sync_compat+0x178/0x180 [ 4.698082] ---[ end trace b4f2db9d9c88610b ]--- [ 4.702721] ------------[ cut here ]------------ [ 4.707329] WARNING: CPU: 5 PID: 369 at drivers/gpu/drm/drm_mode_object.c:243 drm_object_attach_property+0x48/0xb8 <snip> [ 4.833830] Call trace: [ 4.836266] drm_object_attach_property+0x48/0xb8 [ 4.840958] drm_connector_set_panel_orientation+0x84/0xa0 [ 4.846432] boe_panel_get_modes+0x88/0xd8 [ 4.850516] drm_panel_get_modes+0x2c/0x48 [ 4.854600] panel_bridge_get_modes+0x1c/0x28 [ 4.858946] drm_bridge_connector_get_modes+0xa0/0xd4 [ 4.863984] drm_helper_probe_single_connector_modes+0x218/0x700 [ 4.869978] drm_mode_getconnector+0x1b4/0x45c [ 4.874410] drm_ioctl_kernel+0xac/0x128 [ 4.878320] drm_ioctl+0x268/0x410 [ 4.881711] drm_compat_ioctl+0xdc/0xf0 [ 4.885536] __arm64_compat_sys_ioctl+0xc8/0x100 [ 4.890142] el0_svc_common+0xf4/0x1c0 [ 4.893879] do_el0_svc_compat+0x28/0x3c [ 4.897791] el0_svc_compat+0x10/0x1c [ 4.901441] el0_sync_compat_handler+0xa8/0xcc [ 4.905873] el0_sync_compat+0x178/0x180 [ 4.909783] ---[ end trace b4f2db9d9c88610c ]---

Signed-off-by: Hsin-Yi Wang hsinyi@chromium.org Reviewed-by: Sean Paul seanpaul@chromium.org

---

v9->v10: rebase to latest linux-next. v9: https://patchwork.kernel.org/project/linux-mediatek/patch/20220318074825.335... v8: https://patchwork.kernel.org/project/linux-mediatek/patch/20220208084234.168... v7: https://patchwork.kernel.org/project/linux-mediatek/patch/20220208073714.154...

---

drivers/gpu/drm/drm_connector.c | 58 +++++++++++++++++++++++++-------- include/drm/drm_connector.h | 2 ++ 2 files changed, 47 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c index 1c48d162c77e..d68cc78f6684 100644 --- a/drivers/gpu/drm/drm_connector.c +++ b/drivers/gpu/drm/drm_connector.c @@ -1252,7 +1252,7 @@ static const struct drm_prop_enum_list dp_colorspaces[] = {

• INPUT_PROP_DIRECT) will still map 1:1 to the actual LCD panel
• coordinates, so if userspace rotates the picture to adjust for
• the orientation it must also apply the same transformation to the

• • touchscreen input coordinates. This property is initialized by calling

• • touchscreen input coordinates. This property value is set by calling
  • drm_connector_set_panel_orientation() or
  • drm_connector_set_panel_orientation_with_quirk()

@@ -2310,8 +2310,8 @@ EXPORT_SYMBOL(drm_connector_set_vrr_capable_property);

• @connector: connector for which to set the panel-orientation property.
• @panel_orientation: drm_panel_orientation value to set

• • This function sets the connector's panel_orientation and attaches
• • a "panel orientation" property to the connector.

• • This function sets the connector's panel_orientation value. If the property
• • doesn't exist, it will try to create one.
  • Calling this function on a connector where the panel_orientation has
  • already been set is a no-op (e.g. the orientation has been overridden with

@@ -2343,18 +2343,13 @@ int drm_connector_set_panel_orientation(

prop = dev->mode_config.panel_orientation_property; if (!prop) {

• prop = drm_property_create_enum(dev, DRM_MODE_PROP_IMMUTABLE,
  

• 		"panel orientation",
  

• 		drm_panel_orientation_enum_list,
  

• 		ARRAY_SIZE(drm_panel_orientation_enum_list));
  

• if (!prop)
  

• if (drm_connector_init_panel_orientation_property(connector) < 0)
  return -ENOMEM;
  

• dev->mode_config.panel_orientation_property = prop;
  

• prop = dev->mode_config.panel_orientation_property;
  

  }

• drm_object_attach_property(&connector->base, prop,

• 		   info->panel_orientation);
  

• drm_object_property_set_value(&connector->base, prop,

• 		      info->panel_orientation);
  

  return 0;

} EXPORT_SYMBOL(drm_connector_set_panel_orientation); @@ -2362,7 +2357,7 @@ EXPORT_SYMBOL(drm_connector_set_panel_orientation); /**

• drm_connector_set_panel_orientation_with_quirk - set the
• connector's panel_orientation after checking for quirks

• • @connector: connector for which to init the panel-orientation property.

• • @connector: connector for which to set the panel-orientation property.
  • @panel_orientation: drm_panel_orientation value to set
  • @width: width in pixels of the panel, used for panel quirk detection
  • @height: height in pixels of the panel, used for panel quirk detection

@@ -2389,6 +2384,43 @@ int drm_connector_set_panel_orientation_with_quirk( } EXPORT_SYMBOL(drm_connector_set_panel_orientation_with_quirk);

+/**

• • drm_connector_init_panel_orientation_property -
• • create the connector's panel orientation property
• • This function attaches a "panel orientation" property to the connector
• • and initializes its value to DRM_MODE_PANEL_ORIENTATION_UNKNOWN.
• • The value of the property can be set by drm_connector_set_panel_orientation()
• • or drm_connector_set_panel_orientation_with_quirk() later.
• • Returns:
• • Zero on success, negative errno on failure.
• */

+int drm_connector_init_panel_orientation_property(

• struct drm_connector *connector)

+{

• struct drm_device *dev = connector->dev;
• struct drm_property *prop;
• if(dev->mode_config.panel_orientation_property)

• return 0;
  

• prop = drm_property_create_enum(dev, DRM_MODE_PROP_IMMUTABLE,

• 	"panel orientation",
  

• 	drm_panel_orientation_enum_list,
  

• 	ARRAY_SIZE(drm_panel_orientation_enum_list));
  

• if (!prop)

• return -ENOMEM;
  

• dev->mode_config.panel_orientation_property = prop;
• drm_object_attach_property(&connector->base, prop,

• 		   DRM_MODE_PANEL_ORIENTATION_UNKNOWN);
  

DRM_MODE_PANEL_ORIENTATION_UNKNOWN is -1 which is not a valid value for an enum. IOW when the panel-orientation is DRM_MODE_PANEL_ORIENTATION_UNKNOWN then the property should not be created on the drm-connector object at all.

p.s. note that the original drm_connector_set_panel_orientation() avoids ever creating the property when the orientation is unknown because of this bit of code near the top of the function:

/* Don't attach the property if the orientation is unknown */ if (panel_orientation == DRM_MODE_PANEL_ORIENTATION_UNKNOWN) return 0;

Which brings us back to what I said in reply to the coverletter, it seems that you have a probe ordering problem here; and fixing that issue would make this patch-set unnecessary.

Regards,

Hans

...

• return 0;

+} +EXPORT_SYMBOL(drm_connector_init_panel_orientation_property);

static const struct drm_prop_enum_list privacy_screen_enum[] = { { PRIVACY_SCREEN_DISABLED, "Disabled" }, { PRIVACY_SCREEN_ENABLED, "Enabled" }, diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h index 3ac4bf87f257..f0681091c617 100644 --- a/include/drm/drm_connector.h +++ b/include/drm/drm_connector.h @@ -1802,6 +1802,8 @@ int drm_connector_set_panel_orientation_with_quirk( struct drm_connector *connector, enum drm_panel_orientation panel_orientation, int width, int height); +int drm_connector_init_panel_orientation_property(

• struct drm_connector *connector);

int drm_connector_attach_max_bpc_property(struct drm_connector *connector, int min, int max); void drm_connector_create_privacy_screen_properties(struct drm_connector *conn);