[PATCH v8 0/4] Panel rotation patches

[PATCH v8 0/4] Panel rotation patches

[Derek Basehore]

This adds the plumbing for reading panel rotation from the devicetree
and sets up adding a panel property for the panel orientation on
Mediatek SoCs when a rotation is present.

v8 changes:
-added reviewed-by tags
-fixed conflict with i915 patch that recently landed
-Added additional documentation

v7 changes:
-forgot to add static inline

v6 changes:
-added enum declaration to drm_panel.h header

v5 changes:
-rebased

v4 changes:
-fixed some changes made to the i915 driver
-clarified comments on of orientation helper

v3 changes:
-changed from attach/detach callbacks to directly setting fixed panel
 values in drm_panel_attach
-removed update to Documentation
-added separate function for quirked panel orientation property init

v2 changes:
fixed build errors in i915

Derek Basehore (4):
  drm/panel: Add helper for reading DT rotation
  drm/panel: set display info in panel attach
  drm/connector: Split out orientation quirk detection
  drm/mtk: add panel orientation property

 drivers/gpu/drm/drm_connector.c    | 45 ++++++++++++++-----
 drivers/gpu/drm/drm_panel.c        | 70 ++++++++++++++++++++++++++++++
 drivers/gpu/drm/i915/intel_dp.c    |  4 +-
 drivers/gpu/drm/i915/vlv_dsi.c     |  5 +--
 drivers/gpu/drm/mediatek/mtk_dsi.c |  8 ++++
 include/drm/drm_connector.h        |  2 +
 include/drm/drm_panel.h            | 21 +++++++++
 7 files changed, 138 insertions(+), 17 deletions(-)

-- 
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[PATCH v8 1/4] drm/panel: Add helper for reading DT rotation

[Derek Basehore]

This adds a helper function for reading the rotation (panel
orientation) from the device tree.

Signed-off-by: Derek Basehore <dbasehore@chromium.org>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
---
 drivers/gpu/drm/drm_panel.c | 43 +++++++++++++++++++++++++++++++++++++
 include/drm/drm_panel.h     |  9 ++++++++
 2 files changed, 52 insertions(+)

diff --git a/drivers/gpu/drm/drm_panel.c b/drivers/gpu/drm/drm_panel.c
index 6b0bf42039cf..0909b53b74e6 100644
--- a/drivers/gpu/drm/drm_panel.c
+++ b/drivers/gpu/drm/drm_panel.c
@@ -264,6 +264,49 @@ struct drm_panel *of_drm_find_panel(const struct device_node *np)
 	return ERR_PTR(-EPROBE_DEFER);
 }
 EXPORT_SYMBOL(of_drm_find_panel);
+
+/**
+ * of_drm_get_panel_orientation - look up the orientation of the panel through
+ * the "rotation" binding from a device tree node
+ * @np: device tree node of the panel
+ * @orientation: orientation enum to be filled in
+ *
+ * Looks up the rotation of a panel in the device tree. The orientation of the
+ * panel is expressed as a property name "rotation" in the device tree. The
+ * rotation in the device tree is counter clockwise.
+ *
+ * Return: 0 when a valid rotation value (0, 90, 180, or 270) is read or the
+ * rotation property doesn't exist. -EERROR otherwise.
+ */
+int of_drm_get_panel_orientation(const struct device_node *np,
+				 enum drm_panel_orientation *orientation)
+{
+	int rotation, ret;
+
+	ret = of_property_read_u32(np, "rotation", &rotation);
+	if (ret == -EINVAL) {
+		/* Don't return an error if there's no rotation property. */
+		*orientation = DRM_MODE_PANEL_ORIENTATION_UNKNOWN;
+		return 0;
+	}
+
+	if (ret < 0)
+		return ret;
+
+	if (rotation == 0)
+		*orientation = DRM_MODE_PANEL_ORIENTATION_NORMAL;
+	else if (rotation == 90)
+		*orientation = DRM_MODE_PANEL_ORIENTATION_RIGHT_UP;
+	else if (rotation == 180)
+		*orientation = DRM_MODE_PANEL_ORIENTATION_BOTTOM_UP;
+	else if (rotation == 270)
+		*orientation = DRM_MODE_PANEL_ORIENTATION_LEFT_UP;
+	else
+		return -EINVAL;
+
+	return 0;
+}
+EXPORT_SYMBOL(of_drm_get_panel_orientation);
 #endif
 
 MODULE_AUTHOR("Thierry Reding <treding@nvidia.com>");
diff --git a/include/drm/drm_panel.h b/include/drm/drm_panel.h
index 624bd15ecfab..d16158deacdc 100644
--- a/include/drm/drm_panel.h
+++ b/include/drm/drm_panel.h
@@ -34,6 +34,8 @@ struct drm_device;
 struct drm_panel;
 struct display_timing;
 
+enum drm_panel_orientation;
+
 /**
  * struct drm_panel_funcs - perform operations on a given panel
  *
@@ -165,11 +167,18 @@ int drm_panel_get_modes(struct drm_panel *panel);
 
 #if defined(CONFIG_OF) && defined(CONFIG_DRM_PANEL)
 struct drm_panel *of_drm_find_panel(const struct device_node *np);
+int of_drm_get_panel_orientation(const struct device_node *np,
+				 enum drm_panel_orientation *orientation);
 #else
 static inline struct drm_panel *of_drm_find_panel(const struct device_node *np)
 {
 	return ERR_PTR(-ENODEV);
 }
+static inline int of_drm_get_panel_orientation(const struct device_node *np,
+		enum drm_panel_orientation *orientation)
+{
+	return -ENODEV;
+}
 #endif
 
 #endif
-- 
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[PATCH v8 2/4] drm/panel: set display info in panel attach

[Derek Basehore]

Devicetree systems can set panel orientation via a panel binding, but
there's no way, as is, to propagate this setting to the connector,
where the property need to be added.
To address this, this patch sets orientation, as well as other fixed
values for the panel, in the drm_panel_attach function. These values
are stored from probe in the drm_panel struct.

Signed-off-by: Derek Basehore <dbasehore@chromium.org>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
---
 drivers/gpu/drm/drm_panel.c | 28 +++++++++++++++++++++
 include/drm/drm_panel.h     | 50 +++++++++++++++++++++++++++++++++++++
 2 files changed, 78 insertions(+)

diff --git a/drivers/gpu/drm/drm_panel.c b/drivers/gpu/drm/drm_panel.c
index 0909b53b74e6..1cd2b56c9fe6 100644
--- a/drivers/gpu/drm/drm_panel.c
+++ b/drivers/gpu/drm/drm_panel.c
@@ -104,11 +104,23 @@ EXPORT_SYMBOL(drm_panel_remove);
  */
 int drm_panel_attach(struct drm_panel *panel, struct drm_connector *connector)
 {
+	struct drm_display_info *info;
+
 	if (panel->connector)
 		return -EBUSY;
 
 	panel->connector = connector;
 	panel->drm = connector->dev;
+	info = &connector->display_info;
+	info->width_mm = panel->width_mm;
+	info->height_mm = panel->height_mm;
+	info->bpc = panel->bpc;
+	info->panel_orientation = panel->orientation;
+	info->bus_flags = panel->bus_flags;
+	if (panel->bus_formats)
+		drm_display_info_set_bus_formats(&connector->display_info,
+						 panel->bus_formats,
+						 panel->num_bus_formats);
 
 	return 0;
 }
@@ -126,6 +138,22 @@ EXPORT_SYMBOL(drm_panel_attach);
  */
 void drm_panel_detach(struct drm_panel *panel)
 {
+	struct drm_display_info *info;
+
+	if (!panel->connector)
+		goto out;
+
+	info = &panel->connector->display_info;
+	info->width_mm = 0;
+	info->height_mm = 0;
+	info->bpc = 0;
+	info->panel_orientation = DRM_MODE_PANEL_ORIENTATION_UNKNOWN;
+	info->bus_flags = 0;
+	kfree(info->bus_formats);
+	info->bus_formats = NULL;
+	info->num_bus_formats = 0;
+
+out:
 	panel->connector = NULL;
 	panel->drm = NULL;
 }
diff --git a/include/drm/drm_panel.h b/include/drm/drm_panel.h
index d16158deacdc..f3587a54b8ac 100644
--- a/include/drm/drm_panel.h
+++ b/include/drm/drm_panel.h
@@ -141,6 +141,56 @@ struct drm_panel {
 	 */
 	const struct drm_panel_funcs *funcs;
 
+	/**
+	 * @width_mm:
+	 *
+	 * Physical width in mm.
+	 */
+	unsigned int width_mm;
+
+	/**
+	 * @height_mm:
+	 *
+	 * Physical height in mm.
+	 */
+	unsigned int height_mm;
+
+	/**
+	 * @bpc:
+	 *
+	 * Maximum bits per color channel. Used by HDMI and DP outputs.
+	 */
+	unsigned int bpc;
+
+	/**
+	 * @orientation
+	 *
+	 * Installation orientation of the panel with respect to the chassis.
+	 */
+	int orientation;
+
+	/**
+	 * @bus_formats
+	 *
+	 * Pixel data format on the wire.
+	 */
+	const u32 *bus_formats;
+
+	/**
+	 * @num_bus_formats:
+	 *
+	 * Number of elements pointed to by @bus_formats
+	 */
+	unsigned int num_bus_formats;
+
+	/**
+	 * @bus_flags:
+	 *
+	 * Additional information (like pixel signal polarity) for the pixel
+	 * data on the bus.
+	 */
+	u32 bus_flags;
+
 	/**
 	 * @list:
 	 *
-- 
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[PATCH v8 3/4] drm/connector: Split out orientation quirk detection

[Derek Basehore]

Not every platform needs quirk detection for panel orientation, so
split the drm_connector_init_panel_orientation_property into two
functions. One for platforms without the need for quirks, and the
other for platforms that need quirks.

Signed-off-by: Derek Basehore <dbasehore@chromium.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
---
 drivers/gpu/drm/drm_connector.c         | 45 ++++++++++++++++++-------
 drivers/gpu/drm/i915/display/icl_dsi.c  |  2 +-
 drivers/gpu/drm/i915/display/intel_dp.c |  4 +--
 drivers/gpu/drm/i915/display/vlv_dsi.c  |  2 +-
 include/drm/drm_connector.h             |  2 ++
 5 files changed, 39 insertions(+), 16 deletions(-)

diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
index 4c766624b20d..faef25683faf 100644
--- a/drivers/gpu/drm/drm_connector.c
+++ b/drivers/gpu/drm/drm_connector.c
@@ -1989,31 +1989,23 @@ EXPORT_SYMBOL(drm_connector_set_vrr_capable_property);
  * drm_connector_init_panel_orientation_property -
  *	initialize the connecters panel_orientation property
  * @connector: connector for which to init the panel-orientation property.
- * @width: width in pixels of the panel, used for panel quirk detection
- * @height: height in pixels of the panel, used for panel quirk detection
  *
  * This function should only be called for built-in panels, after setting
  * connector->display_info.panel_orientation first (if known).
  *
- * This function will check for platform specific (e.g. DMI based) quirks
- * overriding display_info.panel_orientation first, then if panel_orientation
- * is not DRM_MODE_PANEL_ORIENTATION_UNKNOWN it will attach the
- * "panel orientation" property to the connector.
+ * This function will check if the panel_orientation is not
+ * DRM_MODE_PANEL_ORIENTATION_UNKNOWN. If not, it will attach the "panel
+ * orientation" property to the connector.
  *
  * Returns:
  * Zero on success, negative errno on failure.
  */
 int drm_connector_init_panel_orientation_property(
-	struct drm_connector *connector, int width, int height)
+	struct drm_connector *connector)
 {
 	struct drm_device *dev = connector->dev;
 	struct drm_display_info *info = &connector->display_info;
 	struct drm_property *prop;
-	int orientation_quirk;
-
-	orientation_quirk = drm_get_panel_orientation_quirk(width, height);
-	if (orientation_quirk != DRM_MODE_PANEL_ORIENTATION_UNKNOWN)
-		info->panel_orientation = orientation_quirk;
 
 	if (info->panel_orientation == DRM_MODE_PANEL_ORIENTATION_UNKNOWN)
 		return 0;
@@ -2036,6 +2028,35 @@ int drm_connector_init_panel_orientation_property(
 }
 EXPORT_SYMBOL(drm_connector_init_panel_orientation_property);
 
+/**
+ * drm_connector_init_panel_orientation_property_quirk -
+ *	initialize the connecters panel_orientation property with a quirk
+ *	override
+ * @connector: connector for which to init the panel-orientation property.
+ * @width: width in pixels of the panel, used for panel quirk detection
+ * @height: height in pixels of the panel, used for panel quirk detection
+ *
+ * This function will check for platform specific (e.g. DMI based) quirks
+ * overriding display_info.panel_orientation first, then if panel_orientation
+ * is not DRM_MODE_PANEL_ORIENTATION_UNKNOWN it will attach the
+ * "panel orientation" property to the connector.
+ *
+ * Returns:
+ * Zero on success, negative errno on failure.
+ */
+int drm_connector_init_panel_orientation_property_quirk(
+	struct drm_connector *connector, int width, int height)
+{
+	int orientation_quirk;
+
+	orientation_quirk = drm_get_panel_orientation_quirk(width, height);
+	if (orientation_quirk != DRM_MODE_PANEL_ORIENTATION_UNKNOWN)
+		connector->display_info.panel_orientation = orientation_quirk;
+
+	return drm_connector_init_panel_orientation_property(connector);
+}
+EXPORT_SYMBOL(drm_connector_init_panel_orientation_property_quirk);
+
 int drm_connector_set_obj_prop(struct drm_mode_object *obj,
 				    struct drm_property *property,
 				    uint64_t value)
diff --git a/drivers/gpu/drm/i915/display/icl_dsi.c b/drivers/gpu/drm/i915/display/icl_dsi.c
index 6e398c33a524..483287984090 100644
--- a/drivers/gpu/drm/i915/display/icl_dsi.c
+++ b/drivers/gpu/drm/i915/display/icl_dsi.c
@@ -1538,7 +1538,7 @@ static void icl_dsi_add_properties(struct intel_connector *connector)
 
 	connector->base.display_info.panel_orientation =
 			intel_dsi_get_panel_orientation(connector);
-	drm_connector_init_panel_orientation_property(&connector->base,
+	drm_connector_init_panel_orientation_property_quirk(&connector->base,
 				connector->panel.fixed_mode->hdisplay,
 				connector->panel.fixed_mode->vdisplay);
 }
diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index 921ad0a2f7ba..419413fa8165 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -7076,8 +7076,8 @@ static bool intel_edp_init_connector(struct intel_dp *intel_dp,
 	intel_panel_setup_backlight(connector, pipe);
 
 	if (fixed_mode)
-		drm_connector_init_panel_orientation_property(
-			connector, fixed_mode->hdisplay, fixed_mode->vdisplay);
+		drm_connector_init_panel_orientation_property_quirk(connector,
+				fixed_mode->hdisplay, fixed_mode->vdisplay);
 
 	return true;
 
diff --git a/drivers/gpu/drm/i915/display/vlv_dsi.c b/drivers/gpu/drm/i915/display/vlv_dsi.c
index a71b22bdd95b..46cfb0821c17 100644
--- a/drivers/gpu/drm/i915/display/vlv_dsi.c
+++ b/drivers/gpu/drm/i915/display/vlv_dsi.c
@@ -1634,7 +1634,7 @@ static void vlv_dsi_add_properties(struct intel_connector *connector)
 
 		connector->base.display_info.panel_orientation =
 			vlv_dsi_get_panel_orientation(connector);
-		drm_connector_init_panel_orientation_property(
+		drm_connector_init_panel_orientation_property_quirk(
 				&connector->base,
 				connector->panel.fixed_mode->hdisplay,
 				connector->panel.fixed_mode->vdisplay);
diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
index 681cb590f952..e3416ac11478 100644
--- a/include/drm/drm_connector.h
+++ b/include/drm/drm_connector.h
@@ -1540,6 +1540,8 @@ void drm_connector_set_link_status_property(struct drm_connector *connector,
 void drm_connector_set_vrr_capable_property(
 		struct drm_connector *connector, bool capable);
 int drm_connector_init_panel_orientation_property(
+	struct drm_connector *connector);
+int drm_connector_init_panel_orientation_property_quirk(
 	struct drm_connector *connector, int width, int height);
 int drm_connector_attach_max_bpc_property(struct drm_connector *connector,
 					  int min, int max);
-- 
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[PATCH v8 4/4] drm/mtk: add panel orientation property

[Derek Basehore]

This inits the panel orientation property for the mediatek dsi driver
if the panel orientation (connector.display_info.panel_orientation) is
not DRM_MODE_PANEL_ORIENTATION_UNKNOWN.

Signed-off-by: Derek Basehore <dbasehore@chromium.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: CK Hu <ck.hu@mediatek.com>
---
 drivers/gpu/drm/mediatek/mtk_dsi.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c
index 224afb666881..2936932344eb 100644
--- a/drivers/gpu/drm/mediatek/mtk_dsi.c
+++ b/drivers/gpu/drm/mediatek/mtk_dsi.c
@@ -792,10 +792,18 @@ static int mtk_dsi_create_connector(struct drm_device *drm, struct mtk_dsi *dsi)
 			DRM_ERROR("Failed to attach panel to drm\n");
 			goto err_connector_cleanup;
 		}
+
+		ret = drm_connector_init_panel_orientation_property(&dsi->conn);
+		if (ret) {
+			DRM_ERROR("Failed to init panel orientation\n");
+			goto err_panel_detach;
+		}
 	}
 
 	return 0;
 
+err_panel_detach:
+	drm_panel_detach(dsi->panel);
 err_connector_cleanup:
 	drm_connector_cleanup(&dsi->conn);
 	return ret;
-- 
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Re: [v8,2/4] drm/panel: set display info in panel attach

[james qian wang (Arm Technology China)]

On Wed, Sep 25, 2019 at 03:58:31PM -0700, Derek Basehore wrote:
> Devicetree systems can set panel orientation via a panel binding, but
> there's no way, as is, to propagate this setting to the connector,
> where the property need to be added.
> To address this, this patch sets orientation, as well as other fixed
> values for the panel, in the drm_panel_attach function. These values
> are stored from probe in the drm_panel struct.
> 
> Signed-off-by: Derek Basehore <dbasehore@chromium.org>
> Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
> ---
>  drivers/gpu/drm/drm_panel.c | 28 +++++++++++++++++++++
>  include/drm/drm_panel.h     | 50 +++++++++++++++++++++++++++++++++++++
>  2 files changed, 78 insertions(+)
> 
> diff --git a/drivers/gpu/drm/drm_panel.c b/drivers/gpu/drm/drm_panel.c
> index 0909b53b74e6..1cd2b56c9fe6 100644
> --- a/drivers/gpu/drm/drm_panel.c
> +++ b/drivers/gpu/drm/drm_panel.c
> @@ -104,11 +104,23 @@ EXPORT_SYMBOL(drm_panel_remove);
>   */
>  int drm_panel_attach(struct drm_panel *panel, struct drm_connector *connector)
>  {
> +	struct drm_display_info *info;
> +
>  	if (panel->connector)
>  		return -EBUSY;
>  
>  	panel->connector = connector;
>  	panel->drm = connector->dev;
> +	info = &connector->display_info;
> +	info->width_mm = panel->width_mm;
> +	info->height_mm = panel->height_mm;
> +	info->bpc = panel->bpc;
> +	info->panel_orientation = panel->orientation;
> +	info->bus_flags = panel->bus_flags;
> +	if (panel->bus_formats)
> +		drm_display_info_set_bus_formats(&connector->display_info,
> +						 panel->bus_formats,
> +						 panel->num_bus_formats);
>  
>  	return 0;
>  }
> @@ -126,6 +138,22 @@ EXPORT_SYMBOL(drm_panel_attach);
>   */
>  void drm_panel_detach(struct drm_panel *panel)
>  {
> +	struct drm_display_info *info;
> +
> +	if (!panel->connector)
> +		goto out;
> +
> +	info = &panel->connector->display_info;
> +	info->width_mm = 0;
> +	info->height_mm = 0;
> +	info->bpc = 0;
> +	info->panel_orientation = DRM_MODE_PANEL_ORIENTATION_UNKNOWN;
> +	info->bus_flags = 0;
> +	kfree(info->bus_formats);
> +	info->bus_formats = NULL;
> +	info->num_bus_formats = 0;
> +
> +out:
>  	panel->connector = NULL;
>  	panel->drm = NULL;
>  }
> diff --git a/include/drm/drm_panel.h b/include/drm/drm_panel.h
> index d16158deacdc..f3587a54b8ac 100644
> --- a/include/drm/drm_panel.h
> +++ b/include/drm/drm_panel.h
> @@ -141,6 +141,56 @@ struct drm_panel {
>  	 */
>  	const struct drm_panel_funcs *funcs;
>

All these new added members seems dupliated with drm_display_info,
So I think, can we add a new drm_plane_funcs func:

int (*set_display_info)(struct drm_panel *panel,
                        struct drm_display_info *info);

Then in drm_panel_attach(), via this interface the specific panel
driver can directly set connector->display_info. like

   ...
   if (panel->funcs && panel->funcs->set_display_info)
		panel->funcs->unprepare(panel, connector->display_info);
   ...

Thanks
James

> +	/**
> +	 * @width_mm:
> +	 *
> +	 * Physical width in mm.
> +	 */
> +	unsigned int width_mm;
> +
> +	/**
> +	 * @height_mm:
> +	 *
> +	 * Physical height in mm.
> +	 */
> +	unsigned int height_mm;
> +
> +	/**
> +	 * @bpc:
> +	 *
> +	 * Maximum bits per color channel. Used by HDMI and DP outputs.
> +	 */
> +	unsigned int bpc;
> +
> +	/**
> +	 * @orientation
> +	 *
> +	 * Installation orientation of the panel with respect to the chassis.
> +	 */
> +	int orientation;
> +
> +	/**
> +	 * @bus_formats
> +	 *
> +	 * Pixel data format on the wire.
> +	 */
> +	const u32 *bus_formats;
> +
> +	/**
> +	 * @num_bus_formats:
> +	 *
> +	 * Number of elements pointed to by @bus_formats
> +	 */
> +	unsigned int num_bus_formats;
> +
> +	/**
> +	 * @bus_flags:
> +	 *
> +	 * Additional information (like pixel signal polarity) for the pixel
> +	 * data on the bus.
> +	 */
> +	u32 bus_flags;
> +
>  	/**
>  	 * @list:
>  	 *

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Re: [v8,2/4] drm/panel: set display info in panel attach

[dbasehore .]

On Sat, Sep 28, 2019 at 10:23 PM james qian wang (Arm Technology
China) <james.qian.wang@arm.com> wrote:
>
> On Wed, Sep 25, 2019 at 03:58:31PM -0700, Derek Basehore wrote:
> > Devicetree systems can set panel orientation via a panel binding, but
> > there's no way, as is, to propagate this setting to the connector,
> > where the property need to be added.
> > To address this, this patch sets orientation, as well as other fixed
> > values for the panel, in the drm_panel_attach function. These values
> > are stored from probe in the drm_panel struct.
> >
> > Signed-off-by: Derek Basehore <dbasehore@chromium.org>
> > Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
> > ---
> >  drivers/gpu/drm/drm_panel.c | 28 +++++++++++++++++++++
> >  include/drm/drm_panel.h     | 50 +++++++++++++++++++++++++++++++++++++
> >  2 files changed, 78 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/drm_panel.c b/drivers/gpu/drm/drm_panel.c
> > index 0909b53b74e6..1cd2b56c9fe6 100644
> > --- a/drivers/gpu/drm/drm_panel.c
> > +++ b/drivers/gpu/drm/drm_panel.c
> > @@ -104,11 +104,23 @@ EXPORT_SYMBOL(drm_panel_remove);
> >   */
> >  int drm_panel_attach(struct drm_panel *panel, struct drm_connector *connector)
> >  {
> > +     struct drm_display_info *info;
> > +
> >       if (panel->connector)
> >               return -EBUSY;
> >
> >       panel->connector = connector;
> >       panel->drm = connector->dev;
> > +     info = &connector->display_info;
> > +     info->width_mm = panel->width_mm;
> > +     info->height_mm = panel->height_mm;
> > +     info->bpc = panel->bpc;
> > +     info->panel_orientation = panel->orientation;
> > +     info->bus_flags = panel->bus_flags;
> > +     if (panel->bus_formats)
> > +             drm_display_info_set_bus_formats(&connector->display_info,
> > +                                              panel->bus_formats,
> > +                                              panel->num_bus_formats);
> >
> >       return 0;
> >  }
> > @@ -126,6 +138,22 @@ EXPORT_SYMBOL(drm_panel_attach);
> >   */
> >  void drm_panel_detach(struct drm_panel *panel)
> >  {
> > +     struct drm_display_info *info;
> > +
> > +     if (!panel->connector)
> > +             goto out;
> > +
> > +     info = &panel->connector->display_info;
> > +     info->width_mm = 0;
> > +     info->height_mm = 0;
> > +     info->bpc = 0;
> > +     info->panel_orientation = DRM_MODE_PANEL_ORIENTATION_UNKNOWN;
> > +     info->bus_flags = 0;
> > +     kfree(info->bus_formats);
> > +     info->bus_formats = NULL;
> > +     info->num_bus_formats = 0;
> > +
> > +out:
> >       panel->connector = NULL;
> >       panel->drm = NULL;
> >  }
> > diff --git a/include/drm/drm_panel.h b/include/drm/drm_panel.h
> > index d16158deacdc..f3587a54b8ac 100644
> > --- a/include/drm/drm_panel.h
> > +++ b/include/drm/drm_panel.h
> > @@ -141,6 +141,56 @@ struct drm_panel {
> >        */
> >       const struct drm_panel_funcs *funcs;
> >
>
> All these new added members seems dupliated with drm_display_info,
> So I think, can we add a new drm_plane_funcs func:
>
> int (*set_display_info)(struct drm_panel *panel,
>                         struct drm_display_info *info);

I don't disagree personally, since I originally wrote it this way, but
2 maintainers, Daniel Vetter and Thierry Reding, requested that it be
changed. Unless that decision is reversed, I won't be changing this.

>
> Then in drm_panel_attach(), via this interface the specific panel
> driver can directly set connector->display_info. like
>
>    ...
>    if (panel->funcs && panel->funcs->set_display_info)
>                 panel->funcs->unprepare(panel, connector->display_info);
>    ...
>
> Thanks
> James
>
> > +     /**
> > +      * @width_mm:
> > +      *
> > +      * Physical width in mm.
> > +      */
> > +     unsigned int width_mm;
> > +
> > +     /**
> > +      * @height_mm:
> > +      *
> > +      * Physical height in mm.
> > +      */
> > +     unsigned int height_mm;
> > +
> > +     /**
> > +      * @bpc:
> > +      *
> > +      * Maximum bits per color channel. Used by HDMI and DP outputs.
> > +      */
> > +     unsigned int bpc;
> > +
> > +     /**
> > +      * @orientation
> > +      *
> > +      * Installation orientation of the panel with respect to the chassis.
> > +      */
> > +     int orientation;
> > +
> > +     /**
> > +      * @bus_formats
> > +      *
> > +      * Pixel data format on the wire.
> > +      */
> > +     const u32 *bus_formats;
> > +
> > +     /**
> > +      * @num_bus_formats:
> > +      *
> > +      * Number of elements pointed to by @bus_formats
> > +      */
> > +     unsigned int num_bus_formats;
> > +
> > +     /**
> > +      * @bus_flags:
> > +      *
> > +      * Additional information (like pixel signal polarity) for the pixel
> > +      * data on the bus.
> > +      */
> > +     u32 bus_flags;
> > +
> >       /**
> >        * @list:
> >        *

Thanks for the review

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Re: [PATCH v8 1/4] drm/panel: Add helper for reading DT rotation

[Sean Paul]

On Wed, Sep 25, 2019 at 03:58:30PM -0700, Derek Basehore wrote:
> This adds a helper function for reading the rotation (panel
> orientation) from the device tree.
> 
> Signed-off-by: Derek Basehore <dbasehore@chromium.org>
> Reviewed-by: Sam Ravnborg <sam@ravnborg.org>

The patch LGTM, but I don't see it used anywhere later in the patch? Is there a
panel driver incoming?

Sean

> ---
>  drivers/gpu/drm/drm_panel.c | 43 +++++++++++++++++++++++++++++++++++++
>  include/drm/drm_panel.h     |  9 ++++++++
>  2 files changed, 52 insertions(+)
> 
> diff --git a/drivers/gpu/drm/drm_panel.c b/drivers/gpu/drm/drm_panel.c
> index 6b0bf42039cf..0909b53b74e6 100644
> --- a/drivers/gpu/drm/drm_panel.c
> +++ b/drivers/gpu/drm/drm_panel.c
> @@ -264,6 +264,49 @@ struct drm_panel *of_drm_find_panel(const struct device_node *np)
>  	return ERR_PTR(-EPROBE_DEFER);
>  }
>  EXPORT_SYMBOL(of_drm_find_panel);
> +
> +/**
> + * of_drm_get_panel_orientation - look up the orientation of the panel through
> + * the "rotation" binding from a device tree node
> + * @np: device tree node of the panel
> + * @orientation: orientation enum to be filled in
> + *
> + * Looks up the rotation of a panel in the device tree. The orientation of the
> + * panel is expressed as a property name "rotation" in the device tree. The
> + * rotation in the device tree is counter clockwise.
> + *
> + * Return: 0 when a valid rotation value (0, 90, 180, or 270) is read or the
> + * rotation property doesn't exist. -EERROR otherwise.
> + */
> +int of_drm_get_panel_orientation(const struct device_node *np,
> +				 enum drm_panel_orientation *orientation)
> +{
> +	int rotation, ret;
> +
> +	ret = of_property_read_u32(np, "rotation", &rotation);
> +	if (ret == -EINVAL) {
> +		/* Don't return an error if there's no rotation property. */
> +		*orientation = DRM_MODE_PANEL_ORIENTATION_UNKNOWN;
> +		return 0;
> +	}
> +
> +	if (ret < 0)
> +		return ret;
> +
> +	if (rotation == 0)
> +		*orientation = DRM_MODE_PANEL_ORIENTATION_NORMAL;
> +	else if (rotation == 90)
> +		*orientation = DRM_MODE_PANEL_ORIENTATION_RIGHT_UP;
> +	else if (rotation == 180)
> +		*orientation = DRM_MODE_PANEL_ORIENTATION_BOTTOM_UP;
> +	else if (rotation == 270)
> +		*orientation = DRM_MODE_PANEL_ORIENTATION_LEFT_UP;
> +	else
> +		return -EINVAL;
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL(of_drm_get_panel_orientation);
>  #endif
>  
>  MODULE_AUTHOR("Thierry Reding <treding@nvidia.com>");
> diff --git a/include/drm/drm_panel.h b/include/drm/drm_panel.h
> index 624bd15ecfab..d16158deacdc 100644
> --- a/include/drm/drm_panel.h
> +++ b/include/drm/drm_panel.h
> @@ -34,6 +34,8 @@ struct drm_device;
>  struct drm_panel;
>  struct display_timing;
>  
> +enum drm_panel_orientation;
> +
>  /**
>   * struct drm_panel_funcs - perform operations on a given panel
>   *
> @@ -165,11 +167,18 @@ int drm_panel_get_modes(struct drm_panel *panel);
>  
>  #if defined(CONFIG_OF) && defined(CONFIG_DRM_PANEL)
>  struct drm_panel *of_drm_find_panel(const struct device_node *np);
> +int of_drm_get_panel_orientation(const struct device_node *np,
> +				 enum drm_panel_orientation *orientation);
>  #else
>  static inline struct drm_panel *of_drm_find_panel(const struct device_node *np)
>  {
>  	return ERR_PTR(-ENODEV);
>  }
> +static inline int of_drm_get_panel_orientation(const struct device_node *np,
> +		enum drm_panel_orientation *orientation)
> +{
> +	return -ENODEV;
> +}
>  #endif
>  
>  #endif
> -- 
> 2.23.0.351.gc4317032e6-goog
> 

-- 
Sean Paul, Software Engineer, Google / Chromium OS

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Re: [v8,2/4] drm/panel: set display info in panel attach

[Sean Paul]

On Mon, Sep 30, 2019 at 04:14:54PM -0700, dbasehore . wrote:
> On Sat, Sep 28, 2019 at 10:23 PM james qian wang (Arm Technology
> China) <james.qian.wang@arm.com> wrote:
> >
> > On Wed, Sep 25, 2019 at 03:58:31PM -0700, Derek Basehore wrote:
> > > Devicetree systems can set panel orientation via a panel binding, but
> > > there's no way, as is, to propagate this setting to the connector,
> > > where the property need to be added.
> > > To address this, this patch sets orientation, as well as other fixed
> > > values for the panel, in the drm_panel_attach function. These values
> > > are stored from probe in the drm_panel struct.
> > >
> > > Signed-off-by: Derek Basehore <dbasehore@chromium.org>
> > > Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
> > > ---
> > >  drivers/gpu/drm/drm_panel.c | 28 +++++++++++++++++++++
> > >  include/drm/drm_panel.h     | 50 +++++++++++++++++++++++++++++++++++++
> > >  2 files changed, 78 insertions(+)
> > >
> > > diff --git a/drivers/gpu/drm/drm_panel.c b/drivers/gpu/drm/drm_panel.c
> > > index 0909b53b74e6..1cd2b56c9fe6 100644
> > > --- a/drivers/gpu/drm/drm_panel.c
> > > +++ b/drivers/gpu/drm/drm_panel.c
> > > @@ -104,11 +104,23 @@ EXPORT_SYMBOL(drm_panel_remove);
> > >   */
> > >  int drm_panel_attach(struct drm_panel *panel, struct drm_connector *connector)
> > >  {
> > > +     struct drm_display_info *info;
> > > +
> > >       if (panel->connector)
> > >               return -EBUSY;
> > >
> > >       panel->connector = connector;
> > >       panel->drm = connector->dev;
> > > +     info = &connector->display_info;
> > > +     info->width_mm = panel->width_mm;
> > > +     info->height_mm = panel->height_mm;
> > > +     info->bpc = panel->bpc;
> > > +     info->panel_orientation = panel->orientation;
> > > +     info->bus_flags = panel->bus_flags;
> > > +     if (panel->bus_formats)
> > > +             drm_display_info_set_bus_formats(&connector->display_info,
> > > +                                              panel->bus_formats,
> > > +                                              panel->num_bus_formats);
> > >
> > >       return 0;
> > >  }
> > > @@ -126,6 +138,22 @@ EXPORT_SYMBOL(drm_panel_attach);
> > >   */
> > >  void drm_panel_detach(struct drm_panel *panel)
> > >  {
> > > +     struct drm_display_info *info;
> > > +
> > > +     if (!panel->connector)
> > > +             goto out;
> > > +
> > > +     info = &panel->connector->display_info;
> > > +     info->width_mm = 0;
> > > +     info->height_mm = 0;
> > > +     info->bpc = 0;
> > > +     info->panel_orientation = DRM_MODE_PANEL_ORIENTATION_UNKNOWN;
> > > +     info->bus_flags = 0;
> > > +     kfree(info->bus_formats);
> > > +     info->bus_formats = NULL;
> > > +     info->num_bus_formats = 0;
> > > +
> > > +out:
> > >       panel->connector = NULL;
> > >       panel->drm = NULL;
> > >  }
> > > diff --git a/include/drm/drm_panel.h b/include/drm/drm_panel.h
> > > index d16158deacdc..f3587a54b8ac 100644
> > > --- a/include/drm/drm_panel.h
> > > +++ b/include/drm/drm_panel.h
> > > @@ -141,6 +141,56 @@ struct drm_panel {
> > >        */
> > >       const struct drm_panel_funcs *funcs;
> > >
> >
> > All these new added members seems dupliated with drm_display_info,
> > So I think, can we add a new drm_plane_funcs func:
> >
> > int (*set_display_info)(struct drm_panel *panel,
> >                         struct drm_display_info *info);
> 
> I don't disagree personally, since I originally wrote it this way, but
> 2 maintainers, Daniel Vetter and Thierry Reding, requested that it be
> changed. Unless that decision is reversed, I won't be changing this.
> 

Reading back the feedback on v1, I don't think anyone said they were against
storing a drm_display_info struct in drm_panel (no one really weighed in on
it one way or another). IMO duplicating a bunch of fields feels pretty icky.

I think most fields in drm_display_info have pretty reasonable defaults, so I'd
recommend just storing a copy in drm_panel. As Thierry suggests, we can
populate the dt parts in probe (orientation) and then copy over all or a subset
of the struct to connector on attach.

Sean

> >
> > Then in drm_panel_attach(), via this interface the specific panel
> > driver can directly set connector->display_info. like
> >
> >    ...
> >    if (panel->funcs && panel->funcs->set_display_info)
> >                 panel->funcs->unprepare(panel, connector->display_info);
> >    ...
> >
> > Thanks
> > James
> >
> > > +     /**
> > > +      * @width_mm:
> > > +      *
> > > +      * Physical width in mm.
> > > +      */
> > > +     unsigned int width_mm;
> > > +
> > > +     /**
> > > +      * @height_mm:
> > > +      *
> > > +      * Physical height in mm.
> > > +      */
> > > +     unsigned int height_mm;
> > > +
> > > +     /**
> > > +      * @bpc:
> > > +      *
> > > +      * Maximum bits per color channel. Used by HDMI and DP outputs.
> > > +      */
> > > +     unsigned int bpc;
> > > +
> > > +     /**
> > > +      * @orientation
> > > +      *
> > > +      * Installation orientation of the panel with respect to the chassis.
> > > +      */
> > > +     int orientation;
> > > +
> > > +     /**
> > > +      * @bus_formats
> > > +      *
> > > +      * Pixel data format on the wire.
> > > +      */
> > > +     const u32 *bus_formats;
> > > +
> > > +     /**
> > > +      * @num_bus_formats:
> > > +      *
> > > +      * Number of elements pointed to by @bus_formats
> > > +      */
> > > +     unsigned int num_bus_formats;
> > > +
> > > +     /**
> > > +      * @bus_flags:
> > > +      *
> > > +      * Additional information (like pixel signal polarity) for the pixel
> > > +      * data on the bus.
> > > +      */
> > > +     u32 bus_flags;
> > > +
> > >       /**
> > >        * @list:
> > >        *
> 
> Thanks for the review

-- 
Sean Paul, Software Engineer, Google / Chromium OS

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Re: [PATCH v8 3/4] drm/connector: Split out orientation quirk detection

[Sean Paul]

On Wed, Sep 25, 2019 at 03:58:32PM -0700, Derek Basehore wrote:
> Not every platform needs quirk detection for panel orientation, so
> split the drm_connector_init_panel_orientation_property into two
> functions. One for platforms without the need for quirks, and the
> other for platforms that need quirks.
> 
> Signed-off-by: Derek Basehore <dbasehore@chromium.org>
> Acked-by: Sam Ravnborg <sam@ravnborg.org>

Reviewed-by: Sean Paul <seanpaul@chromium.org>

> ---
>  drivers/gpu/drm/drm_connector.c         | 45 ++++++++++++++++++-------
>  drivers/gpu/drm/i915/display/icl_dsi.c  |  2 +-
>  drivers/gpu/drm/i915/display/intel_dp.c |  4 +--
>  drivers/gpu/drm/i915/display/vlv_dsi.c  |  2 +-
>  include/drm/drm_connector.h             |  2 ++
>  5 files changed, 39 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
> index 4c766624b20d..faef25683faf 100644
> --- a/drivers/gpu/drm/drm_connector.c
> +++ b/drivers/gpu/drm/drm_connector.c
> @@ -1989,31 +1989,23 @@ EXPORT_SYMBOL(drm_connector_set_vrr_capable_property);
>   * drm_connector_init_panel_orientation_property -
>   *	initialize the connecters panel_orientation property
>   * @connector: connector for which to init the panel-orientation property.
> - * @width: width in pixels of the panel, used for panel quirk detection
> - * @height: height in pixels of the panel, used for panel quirk detection
>   *
>   * This function should only be called for built-in panels, after setting
>   * connector->display_info.panel_orientation first (if known).
>   *
> - * This function will check for platform specific (e.g. DMI based) quirks
> - * overriding display_info.panel_orientation first, then if panel_orientation
> - * is not DRM_MODE_PANEL_ORIENTATION_UNKNOWN it will attach the
> - * "panel orientation" property to the connector.
> + * This function will check if the panel_orientation is not
> + * DRM_MODE_PANEL_ORIENTATION_UNKNOWN. If not, it will attach the "panel
> + * orientation" property to the connector.
>   *
>   * Returns:
>   * Zero on success, negative errno on failure.
>   */
>  int drm_connector_init_panel_orientation_property(
> -	struct drm_connector *connector, int width, int height)
> +	struct drm_connector *connector)
>  {
>  	struct drm_device *dev = connector->dev;
>  	struct drm_display_info *info = &connector->display_info;
>  	struct drm_property *prop;
> -	int orientation_quirk;
> -
> -	orientation_quirk = drm_get_panel_orientation_quirk(width, height);
> -	if (orientation_quirk != DRM_MODE_PANEL_ORIENTATION_UNKNOWN)
> -		info->panel_orientation = orientation_quirk;
>  
>  	if (info->panel_orientation == DRM_MODE_PANEL_ORIENTATION_UNKNOWN)
>  		return 0;
> @@ -2036,6 +2028,35 @@ int drm_connector_init_panel_orientation_property(
>  }
>  EXPORT_SYMBOL(drm_connector_init_panel_orientation_property);
>  
> +/**
> + * drm_connector_init_panel_orientation_property_quirk -
> + *	initialize the connecters panel_orientation property with a quirk
> + *	override
> + * @connector: connector for which to init the panel-orientation property.
> + * @width: width in pixels of the panel, used for panel quirk detection
> + * @height: height in pixels of the panel, used for panel quirk detection
> + *
> + * This function will check for platform specific (e.g. DMI based) quirks
> + * overriding display_info.panel_orientation first, then if panel_orientation
> + * is not DRM_MODE_PANEL_ORIENTATION_UNKNOWN it will attach the
> + * "panel orientation" property to the connector.
> + *
> + * Returns:
> + * Zero on success, negative errno on failure.
> + */
> +int drm_connector_init_panel_orientation_property_quirk(
> +	struct drm_connector *connector, int width, int height)
> +{
> +	int orientation_quirk;
> +
> +	orientation_quirk = drm_get_panel_orientation_quirk(width, height);
> +	if (orientation_quirk != DRM_MODE_PANEL_ORIENTATION_UNKNOWN)
> +		connector->display_info.panel_orientation = orientation_quirk;
> +
> +	return drm_connector_init_panel_orientation_property(connector);
> +}
> +EXPORT_SYMBOL(drm_connector_init_panel_orientation_property_quirk);
> +
>  int drm_connector_set_obj_prop(struct drm_mode_object *obj,
>  				    struct drm_property *property,
>  				    uint64_t value)
> diff --git a/drivers/gpu/drm/i915/display/icl_dsi.c b/drivers/gpu/drm/i915/display/icl_dsi.c
> index 6e398c33a524..483287984090 100644
> --- a/drivers/gpu/drm/i915/display/icl_dsi.c
> +++ b/drivers/gpu/drm/i915/display/icl_dsi.c
> @@ -1538,7 +1538,7 @@ static void icl_dsi_add_properties(struct intel_connector *connector)
>  
>  	connector->base.display_info.panel_orientation =
>  			intel_dsi_get_panel_orientation(connector);
> -	drm_connector_init_panel_orientation_property(&connector->base,
> +	drm_connector_init_panel_orientation_property_quirk(&connector->base,
>  				connector->panel.fixed_mode->hdisplay,
>  				connector->panel.fixed_mode->vdisplay);
>  }
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
> index 921ad0a2f7ba..419413fa8165 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -7076,8 +7076,8 @@ static bool intel_edp_init_connector(struct intel_dp *intel_dp,
>  	intel_panel_setup_backlight(connector, pipe);
>  
>  	if (fixed_mode)
> -		drm_connector_init_panel_orientation_property(
> -			connector, fixed_mode->hdisplay, fixed_mode->vdisplay);
> +		drm_connector_init_panel_orientation_property_quirk(connector,
> +				fixed_mode->hdisplay, fixed_mode->vdisplay);
>  
>  	return true;
>  
> diff --git a/drivers/gpu/drm/i915/display/vlv_dsi.c b/drivers/gpu/drm/i915/display/vlv_dsi.c
> index a71b22bdd95b..46cfb0821c17 100644
> --- a/drivers/gpu/drm/i915/display/vlv_dsi.c
> +++ b/drivers/gpu/drm/i915/display/vlv_dsi.c
> @@ -1634,7 +1634,7 @@ static void vlv_dsi_add_properties(struct intel_connector *connector)
>  
>  		connector->base.display_info.panel_orientation =
>  			vlv_dsi_get_panel_orientation(connector);
> -		drm_connector_init_panel_orientation_property(
> +		drm_connector_init_panel_orientation_property_quirk(
>  				&connector->base,
>  				connector->panel.fixed_mode->hdisplay,
>  				connector->panel.fixed_mode->vdisplay);
> diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
> index 681cb590f952..e3416ac11478 100644
> --- a/include/drm/drm_connector.h
> +++ b/include/drm/drm_connector.h
> @@ -1540,6 +1540,8 @@ void drm_connector_set_link_status_property(struct drm_connector *connector,
>  void drm_connector_set_vrr_capable_property(
>  		struct drm_connector *connector, bool capable);
>  int drm_connector_init_panel_orientation_property(
> +	struct drm_connector *connector);
> +int drm_connector_init_panel_orientation_property_quirk(
>  	struct drm_connector *connector, int width, int height);
>  int drm_connector_attach_max_bpc_property(struct drm_connector *connector,
>  					  int min, int max);
> -- 
> 2.23.0.351.gc4317032e6-goog
> 

-- 
Sean Paul, Software Engineer, Google / Chromium OS

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Re: [PATCH v8 4/4] drm/mtk: add panel orientation property

[Sean Paul]

On Wed, Sep 25, 2019 at 03:58:33PM -0700, Derek Basehore wrote:
> This inits the panel orientation property for the mediatek dsi driver
> if the panel orientation (connector.display_info.panel_orientation) is
> not DRM_MODE_PANEL_ORIENTATION_UNKNOWN.
> 
> Signed-off-by: Derek Basehore <dbasehore@chromium.org>
> Acked-by: Sam Ravnborg <sam@ravnborg.org>
> Reviewed-by: CK Hu <ck.hu@mediatek.com>

Reviewed-by: Sean Paul <seanpaul@chromium.org>

> ---
>  drivers/gpu/drm/mediatek/mtk_dsi.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c
> index 224afb666881..2936932344eb 100644
> --- a/drivers/gpu/drm/mediatek/mtk_dsi.c
> +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c
> @@ -792,10 +792,18 @@ static int mtk_dsi_create_connector(struct drm_device *drm, struct mtk_dsi *dsi)
>  			DRM_ERROR("Failed to attach panel to drm\n");
>  			goto err_connector_cleanup;
>  		}
> +
> +		ret = drm_connector_init_panel_orientation_property(&dsi->conn);
> +		if (ret) {
> +			DRM_ERROR("Failed to init panel orientation\n");
> +			goto err_panel_detach;
> +		}
>  	}
>  
>  	return 0;
>  
> +err_panel_detach:
> +	drm_panel_detach(dsi->panel);
>  err_connector_cleanup:
>  	drm_connector_cleanup(&dsi->conn);
>  	return ret;
> -- 
> 2.23.0.351.gc4317032e6-goog
> 

-- 
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Re: [v8,2/4] drm/panel: set display info in panel attach

[dbasehore .]

On Mon, Oct 7, 2019 at 9:44 AM Sean Paul <sean@poorly.run> wrote:
>
> On Mon, Sep 30, 2019 at 04:14:54PM -0700, dbasehore . wrote:
> > On Sat, Sep 28, 2019 at 10:23 PM james qian wang (Arm Technology
> > China) <james.qian.wang@arm.com> wrote:
> > >
> > > On Wed, Sep 25, 2019 at 03:58:31PM -0700, Derek Basehore wrote:
> > > > Devicetree systems can set panel orientation via a panel binding, but
> > > > there's no way, as is, to propagate this setting to the connector,
> > > > where the property need to be added.
> > > > To address this, this patch sets orientation, as well as other fixed
> > > > values for the panel, in the drm_panel_attach function. These values
> > > > are stored from probe in the drm_panel struct.
> > > >
> > > > Signed-off-by: Derek Basehore <dbasehore@chromium.org>
> > > > Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
> > > > ---
> > > >  drivers/gpu/drm/drm_panel.c | 28 +++++++++++++++++++++
> > > >  include/drm/drm_panel.h     | 50 +++++++++++++++++++++++++++++++++++++
> > > >  2 files changed, 78 insertions(+)
> > > >
> > > > diff --git a/drivers/gpu/drm/drm_panel.c b/drivers/gpu/drm/drm_panel.c
> > > > index 0909b53b74e6..1cd2b56c9fe6 100644
> > > > --- a/drivers/gpu/drm/drm_panel.c
> > > > +++ b/drivers/gpu/drm/drm_panel.c
> > > > @@ -104,11 +104,23 @@ EXPORT_SYMBOL(drm_panel_remove);
> > > >   */
> > > >  int drm_panel_attach(struct drm_panel *panel, struct drm_connector *connector)
> > > >  {
> > > > +     struct drm_display_info *info;
> > > > +
> > > >       if (panel->connector)
> > > >               return -EBUSY;
> > > >
> > > >       panel->connector = connector;
> > > >       panel->drm = connector->dev;
> > > > +     info = &connector->display_info;
> > > > +     info->width_mm = panel->width_mm;
> > > > +     info->height_mm = panel->height_mm;
> > > > +     info->bpc = panel->bpc;
> > > > +     info->panel_orientation = panel->orientation;
> > > > +     info->bus_flags = panel->bus_flags;
> > > > +     if (panel->bus_formats)
> > > > +             drm_display_info_set_bus_formats(&connector->display_info,
> > > > +                                              panel->bus_formats,
> > > > +                                              panel->num_bus_formats);
> > > >
> > > >       return 0;
> > > >  }
> > > > @@ -126,6 +138,22 @@ EXPORT_SYMBOL(drm_panel_attach);
> > > >   */
> > > >  void drm_panel_detach(struct drm_panel *panel)
> > > >  {
> > > > +     struct drm_display_info *info;
> > > > +
> > > > +     if (!panel->connector)
> > > > +             goto out;
> > > > +
> > > > +     info = &panel->connector->display_info;
> > > > +     info->width_mm = 0;
> > > > +     info->height_mm = 0;
> > > > +     info->bpc = 0;
> > > > +     info->panel_orientation = DRM_MODE_PANEL_ORIENTATION_UNKNOWN;
> > > > +     info->bus_flags = 0;
> > > > +     kfree(info->bus_formats);
> > > > +     info->bus_formats = NULL;
> > > > +     info->num_bus_formats = 0;
> > > > +
> > > > +out:
> > > >       panel->connector = NULL;
> > > >       panel->drm = NULL;
> > > >  }
> > > > diff --git a/include/drm/drm_panel.h b/include/drm/drm_panel.h
> > > > index d16158deacdc..f3587a54b8ac 100644
> > > > --- a/include/drm/drm_panel.h
> > > > +++ b/include/drm/drm_panel.h
> > > > @@ -141,6 +141,56 @@ struct drm_panel {
> > > >        */
> > > >       const struct drm_panel_funcs *funcs;
> > > >
> > >
> > > All these new added members seems dupliated with drm_display_info,
> > > So I think, can we add a new drm_plane_funcs func:
> > >
> > > int (*set_display_info)(struct drm_panel *panel,
> > >                         struct drm_display_info *info);
> >
> > I don't disagree personally, since I originally wrote it this way, but
> > 2 maintainers, Daniel Vetter and Thierry Reding, requested that it be
> > changed. Unless that decision is reversed, I won't be changing this.
> >
>
> Reading back the feedback on v1, I don't think anyone said they were against
> storing a drm_display_info struct in drm_panel (no one really weighed in on
> it one way or another). IMO duplicating a bunch of fields feels pretty icky.

Thanks for the review. Should we duplicate the entire struct, or just
create a sub-struct, say, physical_properties that will be part of
drm_display_info and drm_panel?

>
> I think most fields in drm_display_info have pretty reasonable defaults, so I'd
> recommend just storing a copy in drm_panel. As Thierry suggests, we can
> populate the dt parts in probe (orientation) and then copy over all or a subset
> of the struct to connector on attach.
>
> Sean
>
> > >
> > > Then in drm_panel_attach(), via this interface the specific panel
> > > driver can directly set connector->display_info. like
> > >
> > >    ...
> > >    if (panel->funcs && panel->funcs->set_display_info)
> > >                 panel->funcs->unprepare(panel, connector->display_info);
> > >    ...
> > >
> > > Thanks
> > > James
> > >
> > > > +     /**
> > > > +      * @width_mm:
> > > > +      *
> > > > +      * Physical width in mm.
> > > > +      */
> > > > +     unsigned int width_mm;
> > > > +
> > > > +     /**
> > > > +      * @height_mm:
> > > > +      *
> > > > +      * Physical height in mm.
> > > > +      */
> > > > +     unsigned int height_mm;
> > > > +
> > > > +     /**
> > > > +      * @bpc:
> > > > +      *
> > > > +      * Maximum bits per color channel. Used by HDMI and DP outputs.
> > > > +      */
> > > > +     unsigned int bpc;
> > > > +
> > > > +     /**
> > > > +      * @orientation
> > > > +      *
> > > > +      * Installation orientation of the panel with respect to the chassis.
> > > > +      */
> > > > +     int orientation;
> > > > +
> > > > +     /**
> > > > +      * @bus_formats
> > > > +      *
> > > > +      * Pixel data format on the wire.
> > > > +      */
> > > > +     const u32 *bus_formats;
> > > > +
> > > > +     /**
> > > > +      * @num_bus_formats:
> > > > +      *
> > > > +      * Number of elements pointed to by @bus_formats
> > > > +      */
> > > > +     unsigned int num_bus_formats;
> > > > +
> > > > +     /**
> > > > +      * @bus_flags:
> > > > +      *
> > > > +      * Additional information (like pixel signal polarity) for the pixel
> > > > +      * data on the bus.
> > > > +      */
> > > > +     u32 bus_flags;
> > > > +
> > > >       /**
> > > >        * @list:
> > > >        *
> >
> > Thanks for the review
>
> --
> Sean Paul, Software Engineer, Google / Chromium OS

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Re: [PATCH v8 1/4] drm/panel: Add helper for reading DT rotation

[dbasehore .]

On Mon, Oct 7, 2019 at 9:38 AM Sean Paul <sean@poorly.run> wrote:
>
> On Wed, Sep 25, 2019 at 03:58:30PM -0700, Derek Basehore wrote:
> > This adds a helper function for reading the rotation (panel
> > orientation) from the device tree.
> >
> > Signed-off-by: Derek Basehore <dbasehore@chromium.org>
> > Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
>
> The patch LGTM, but I don't see it used anywhere later in the patch? Is there a
> panel driver incoming?

Yeah, the boe-tv101wum-nl6 panel will use it. It's not in the patch
currently sent upstream since I don't want to step on their toes, but
I plan on sending a patch to add it as soon as that is merged.

I could hold back on this patch until that panel driver is merged too.
Another alternative is to throw this into the generic drm_panel code,
but there's no obvious place to put it since DRM seems to leave
reading the DTS up to the panel drivers themselves.

>
> Sean
>
> > ---
> >  drivers/gpu/drm/drm_panel.c | 43 +++++++++++++++++++++++++++++++++++++
> >  include/drm/drm_panel.h     |  9 ++++++++
> >  2 files changed, 52 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/drm_panel.c b/drivers/gpu/drm/drm_panel.c
> > index 6b0bf42039cf..0909b53b74e6 100644
> > --- a/drivers/gpu/drm/drm_panel.c
> > +++ b/drivers/gpu/drm/drm_panel.c
> > @@ -264,6 +264,49 @@ struct drm_panel *of_drm_find_panel(const struct device_node *np)
> >       return ERR_PTR(-EPROBE_DEFER);
> >  }
> >  EXPORT_SYMBOL(of_drm_find_panel);
> > +
> > +/**
> > + * of_drm_get_panel_orientation - look up the orientation of the panel through
> > + * the "rotation" binding from a device tree node
> > + * @np: device tree node of the panel
> > + * @orientation: orientation enum to be filled in
> > + *
> > + * Looks up the rotation of a panel in the device tree. The orientation of the
> > + * panel is expressed as a property name "rotation" in the device tree. The
> > + * rotation in the device tree is counter clockwise.
> > + *
> > + * Return: 0 when a valid rotation value (0, 90, 180, or 270) is read or the
> > + * rotation property doesn't exist. -EERROR otherwise.
> > + */
> > +int of_drm_get_panel_orientation(const struct device_node *np,
> > +                              enum drm_panel_orientation *orientation)
> > +{
> > +     int rotation, ret;
> > +
> > +     ret = of_property_read_u32(np, "rotation", &rotation);
> > +     if (ret == -EINVAL) {
> > +             /* Don't return an error if there's no rotation property. */
> > +             *orientation = DRM_MODE_PANEL_ORIENTATION_UNKNOWN;
> > +             return 0;
> > +     }
> > +
> > +     if (ret < 0)
> > +             return ret;
> > +
> > +     if (rotation == 0)
> > +             *orientation = DRM_MODE_PANEL_ORIENTATION_NORMAL;
> > +     else if (rotation == 90)
> > +             *orientation = DRM_MODE_PANEL_ORIENTATION_RIGHT_UP;
> > +     else if (rotation == 180)
> > +             *orientation = DRM_MODE_PANEL_ORIENTATION_BOTTOM_UP;
> > +     else if (rotation == 270)
> > +             *orientation = DRM_MODE_PANEL_ORIENTATION_LEFT_UP;
> > +     else
> > +             return -EINVAL;
> > +
> > +     return 0;
> > +}
> > +EXPORT_SYMBOL(of_drm_get_panel_orientation);
> >  #endif
> >
> >  MODULE_AUTHOR("Thierry Reding <treding@nvidia.com>");
> > diff --git a/include/drm/drm_panel.h b/include/drm/drm_panel.h
> > index 624bd15ecfab..d16158deacdc 100644
> > --- a/include/drm/drm_panel.h
> > +++ b/include/drm/drm_panel.h
> > @@ -34,6 +34,8 @@ struct drm_device;
> >  struct drm_panel;
> >  struct display_timing;
> >
> > +enum drm_panel_orientation;
> > +
> >  /**
> >   * struct drm_panel_funcs - perform operations on a given panel
> >   *
> > @@ -165,11 +167,18 @@ int drm_panel_get_modes(struct drm_panel *panel);
> >
> >  #if defined(CONFIG_OF) && defined(CONFIG_DRM_PANEL)
> >  struct drm_panel *of_drm_find_panel(const struct device_node *np);
> > +int of_drm_get_panel_orientation(const struct device_node *np,
> > +                              enum drm_panel_orientation *orientation);
> >  #else
> >  static inline struct drm_panel *of_drm_find_panel(const struct device_node *np)
> >  {
> >       return ERR_PTR(-ENODEV);
> >  }
> > +static inline int of_drm_get_panel_orientation(const struct device_node *np,
> > +             enum drm_panel_orientation *orientation)
> > +{
> > +     return -ENODEV;
> > +}
> >  #endif
> >
> >  #endif
> > --
> > 2.23.0.351.gc4317032e6-goog
> >
>
> --
> Sean Paul, Software Engineer, Google / Chromium OS

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Re: [PATCH v8 1/4] drm/panel: Add helper for reading DT rotation

[Sean Paul]

On Mon, Oct 07, 2019 at 03:12:00PM -0700, dbasehore . wrote:
> On Mon, Oct 7, 2019 at 9:38 AM Sean Paul <sean@poorly.run> wrote:
> >
> > On Wed, Sep 25, 2019 at 03:58:30PM -0700, Derek Basehore wrote:
> > > This adds a helper function for reading the rotation (panel
> > > orientation) from the device tree.
> > >
> > > Signed-off-by: Derek Basehore <dbasehore@chromium.org>
> > > Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
> >
> > The patch LGTM, but I don't see it used anywhere later in the patch? Is there a
> > panel driver incoming?
> 
> Yeah, the boe-tv101wum-nl6 panel will use it. It's not in the patch
> currently sent upstream since I don't want to step on their toes, but
> I plan on sending a patch to add it as soon as that is merged.
> 
> I could hold back on this patch until that panel driver is merged too.

Yeah, I think it's probably best. I don't anticipate any changes will be
required, but it's always best to review the code end-to-end.

I haven't checked in on that review, but if it's close to landing, you can also
add a patch to this stack that is based on the in-flight patches. That way we can
get all the review out of the way and then when the panel lands, we can apply
your add-on with the rest of the series.

Sean

> Another alternative is to throw this into the generic drm_panel code,
> but there's no obvious place to put it since DRM seems to leave
> reading the DTS up to the panel drivers themselves.
> 
> >
> > Sean
> >
> > > ---
> > >  drivers/gpu/drm/drm_panel.c | 43 +++++++++++++++++++++++++++++++++++++
> > >  include/drm/drm_panel.h     |  9 ++++++++
> > >  2 files changed, 52 insertions(+)
> > >
> > > diff --git a/drivers/gpu/drm/drm_panel.c b/drivers/gpu/drm/drm_panel.c
> > > index 6b0bf42039cf..0909b53b74e6 100644
> > > --- a/drivers/gpu/drm/drm_panel.c
> > > +++ b/drivers/gpu/drm/drm_panel.c
> > > @@ -264,6 +264,49 @@ struct drm_panel *of_drm_find_panel(const struct device_node *np)
> > >       return ERR_PTR(-EPROBE_DEFER);
> > >  }
> > >  EXPORT_SYMBOL(of_drm_find_panel);
> > > +
> > > +/**
> > > + * of_drm_get_panel_orientation - look up the orientation of the panel through
> > > + * the "rotation" binding from a device tree node
> > > + * @np: device tree node of the panel
> > > + * @orientation: orientation enum to be filled in
> > > + *
> > > + * Looks up the rotation of a panel in the device tree. The orientation of the
> > > + * panel is expressed as a property name "rotation" in the device tree. The
> > > + * rotation in the device tree is counter clockwise.
> > > + *
> > > + * Return: 0 when a valid rotation value (0, 90, 180, or 270) is read or the
> > > + * rotation property doesn't exist. -EERROR otherwise.
> > > + */
> > > +int of_drm_get_panel_orientation(const struct device_node *np,
> > > +                              enum drm_panel_orientation *orientation)
> > > +{
> > > +     int rotation, ret;
> > > +
> > > +     ret = of_property_read_u32(np, "rotation", &rotation);
> > > +     if (ret == -EINVAL) {
> > > +             /* Don't return an error if there's no rotation property. */
> > > +             *orientation = DRM_MODE_PANEL_ORIENTATION_UNKNOWN;
> > > +             return 0;
> > > +     }
> > > +
> > > +     if (ret < 0)
> > > +             return ret;
> > > +
> > > +     if (rotation == 0)
> > > +             *orientation = DRM_MODE_PANEL_ORIENTATION_NORMAL;
> > > +     else if (rotation == 90)
> > > +             *orientation = DRM_MODE_PANEL_ORIENTATION_RIGHT_UP;
> > > +     else if (rotation == 180)
> > > +             *orientation = DRM_MODE_PANEL_ORIENTATION_BOTTOM_UP;
> > > +     else if (rotation == 270)
> > > +             *orientation = DRM_MODE_PANEL_ORIENTATION_LEFT_UP;
> > > +     else
> > > +             return -EINVAL;
> > > +
> > > +     return 0;
> > > +}
> > > +EXPORT_SYMBOL(of_drm_get_panel_orientation);
> > >  #endif
> > >
> > >  MODULE_AUTHOR("Thierry Reding <treding@nvidia.com>");
> > > diff --git a/include/drm/drm_panel.h b/include/drm/drm_panel.h
> > > index 624bd15ecfab..d16158deacdc 100644
> > > --- a/include/drm/drm_panel.h
> > > +++ b/include/drm/drm_panel.h
> > > @@ -34,6 +34,8 @@ struct drm_device;
> > >  struct drm_panel;
> > >  struct display_timing;
> > >
> > > +enum drm_panel_orientation;
> > > +
> > >  /**
> > >   * struct drm_panel_funcs - perform operations on a given panel
> > >   *
> > > @@ -165,11 +167,18 @@ int drm_panel_get_modes(struct drm_panel *panel);
> > >
> > >  #if defined(CONFIG_OF) && defined(CONFIG_DRM_PANEL)
> > >  struct drm_panel *of_drm_find_panel(const struct device_node *np);
> > > +int of_drm_get_panel_orientation(const struct device_node *np,
> > > +                              enum drm_panel_orientation *orientation);
> > >  #else
> > >  static inline struct drm_panel *of_drm_find_panel(const struct device_node *np)
> > >  {
> > >       return ERR_PTR(-ENODEV);
> > >  }
> > > +static inline int of_drm_get_panel_orientation(const struct device_node *np,
> > > +             enum drm_panel_orientation *orientation)
> > > +{
> > > +     return -ENODEV;
> > > +}
> > >  #endif
> > >
> > >  #endif
> > > --
> > > 2.23.0.351.gc4317032e6-goog
> > >
> >
> > --
> > Sean Paul, Software Engineer, Google / Chromium OS

-- 
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Re: [v8,2/4] drm/panel: set display info in panel attach

[Sean Paul]

/snip

> > > > > diff --git a/include/drm/drm_panel.h b/include/drm/drm_panel.h
> > > > > index d16158deacdc..f3587a54b8ac 100644
> > > > > --- a/include/drm/drm_panel.h
> > > > > +++ b/include/drm/drm_panel.h
> > > > > @@ -141,6 +141,56 @@ struct drm_panel {
> > > > >        */
> > > > >       const struct drm_panel_funcs *funcs;
> > > > >
> > > >
> > > > All these new added members seems dupliated with drm_display_info,
> > > > So I think, can we add a new drm_plane_funcs func:
> > > >
> > > > int (*set_display_info)(struct drm_panel *panel,
> > > >                         struct drm_display_info *info);
> > >
> > > I don't disagree personally, since I originally wrote it this way, but
> > > 2 maintainers, Daniel Vetter and Thierry Reding, requested that it be
> > > changed. Unless that decision is reversed, I won't be changing this.
> > >
> >
> > Reading back the feedback on v1, I don't think anyone said they were against
> > storing a drm_display_info struct in drm_panel (no one really weighed in on
> > it one way or another). IMO duplicating a bunch of fields feels pretty icky.
> 
> Thanks for the review. Should we duplicate the entire struct, or just
> create a sub-struct, say, physical_properties that will be part of
> drm_display_info and drm_panel?

That's a good idea, but I think you can use the entire struct. Everything has
reasonable default values and I think it might be difficult to draw a line in
the sand as to which fields will or won't be useful for panels going forward.
Best for drivers to just treat the info in drm_display_info as best effort and
have good defaults IMO.

Sean

> 
> >
> > I think most fields in drm_display_info have pretty reasonable defaults, so I'd
> > recommend just storing a copy in drm_panel. As Thierry suggests, we can
> > populate the dt parts in probe (orientation) and then copy over all or a subset
> > of the struct to connector on attach.
> >
> > Sean
> >
> > > >
> > > > Then in drm_panel_attach(), via this interface the specific panel
> > > > driver can directly set connector->display_info. like
> > > >
> > > >    ...
> > > >    if (panel->funcs && panel->funcs->set_display_info)
> > > >                 panel->funcs->unprepare(panel, connector->display_info);
> > > >    ...
> > > >
> > > > Thanks
> > > > James
> > > >
> > > > > +     /**
> > > > > +      * @width_mm:
> > > > > +      *
> > > > > +      * Physical width in mm.
> > > > > +      */
> > > > > +     unsigned int width_mm;
> > > > > +
> > > > > +     /**
> > > > > +      * @height_mm:
> > > > > +      *
> > > > > +      * Physical height in mm.
> > > > > +      */
> > > > > +     unsigned int height_mm;
> > > > > +
> > > > > +     /**
> > > > > +      * @bpc:
> > > > > +      *
> > > > > +      * Maximum bits per color channel. Used by HDMI and DP outputs.
> > > > > +      */
> > > > > +     unsigned int bpc;
> > > > > +
> > > > > +     /**
> > > > > +      * @orientation
> > > > > +      *
> > > > > +      * Installation orientation of the panel with respect to the chassis.
> > > > > +      */
> > > > > +     int orientation;
> > > > > +
> > > > > +     /**
> > > > > +      * @bus_formats
> > > > > +      *
> > > > > +      * Pixel data format on the wire.
> > > > > +      */
> > > > > +     const u32 *bus_formats;
> > > > > +
> > > > > +     /**
> > > > > +      * @num_bus_formats:
> > > > > +      *
> > > > > +      * Number of elements pointed to by @bus_formats
> > > > > +      */
> > > > > +     unsigned int num_bus_formats;
> > > > > +
> > > > > +     /**
> > > > > +      * @bus_flags:
> > > > > +      *
> > > > > +      * Additional information (like pixel signal polarity) for the pixel
> > > > > +      * data on the bus.
> > > > > +      */
> > > > > +     u32 bus_flags;
> > > > > +
> > > > >       /**
> > > > >        * @list:
> > > > >        *
> > >
> > > Thanks for the review
> >
> > --
> > Sean Paul, Software Engineer, Google / Chromium OS

-- 
Sean Paul, Software Engineer, Google / Chromium OS

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