[v3,6/7] drm: sun4i: dsi: Use drm_panel_bridge, connector API

Message ID 20210214194102.126146-7-jagan@amarulasolutions.com
State New
Headers show
Series
  • drm: sun4i: dsi: Convert drm bridge
Related show

Commit Message

Jagan Teki Feb. 14, 2021, 7:41 p.m. UTC
Use drm_panel_bridge to replace manual panel handling code.

This simplifies the driver to allows all components in the
display pipeline to be treated as bridges, paving the way
to generic connector handling.

Use drm_bridge_connector_init to create a connector for display
pipelines that use drm_bridge.

This allows splitting connector operations across multiple bridges
when necessary, instead of having the last bridge in the chain
creating the connector and handling all connector operations
internally.

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
---
Changes for v3:
- new patch

 drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 108 +++++++------------------
 drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h |   7 --
 2 files changed, 27 insertions(+), 88 deletions(-)

Comments

Maxime Ripard Feb. 26, 2021, 4:57 p.m. UTC | #1
Hi,

On Mon, Feb 15, 2021 at 01:11:01AM +0530, Jagan Teki wrote:
> Use drm_panel_bridge to replace manual panel handling code.
>
> This simplifies the driver to allows all components in the
> display pipeline to be treated as bridges, paving the way
> to generic connector handling.
>
> Use drm_bridge_connector_init to create a connector for display
> pipelines that use drm_bridge.
>
> This allows splitting connector operations across multiple bridges
> when necessary, instead of having the last bridge in the chain
> creating the connector and handling all connector operations
> internally.
>
> Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>

Most of the code removed in that patch was actually introduced earlier
which feels a bit weird. Is there a reason we can't do that one first,
and then introduce the bridge support?

Maxime
Jagan Teki Feb. 26, 2021, 5:10 p.m. UTC | #2
On Fri, Feb 26, 2021 at 10:27 PM Maxime Ripard <mripard@kernel.org> wrote:
>
> Hi,
>
> On Mon, Feb 15, 2021 at 01:11:01AM +0530, Jagan Teki wrote:
> > Use drm_panel_bridge to replace manual panel handling code.
> >
> > This simplifies the driver to allows all components in the
> > display pipeline to be treated as bridges, paving the way
> > to generic connector handling.
> >
> > Use drm_bridge_connector_init to create a connector for display
> > pipelines that use drm_bridge.
> >
> > This allows splitting connector operations across multiple bridges
> > when necessary, instead of having the last bridge in the chain
> > creating the connector and handling all connector operations
> > internally.
> >
> > Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
>
> Most of the code removed in that patch was actually introduced earlier
> which feels a bit weird. Is there a reason we can't do that one first,
> and then introduce the bridge support?

This patch adds new bridge API's which requires the driver has to
support the bridge first.

Jagan.
Maxime Ripard March 2, 2021, 4:35 p.m. UTC | #3
On Fri, Feb 26, 2021 at 10:40:24PM +0530, Jagan Teki wrote:
> On Fri, Feb 26, 2021 at 10:27 PM Maxime Ripard <mripard@kernel.org> wrote:
> >
> > Hi,
> >
> > On Mon, Feb 15, 2021 at 01:11:01AM +0530, Jagan Teki wrote:
> > > Use drm_panel_bridge to replace manual panel handling code.
> > >
> > > This simplifies the driver to allows all components in the
> > > display pipeline to be treated as bridges, paving the way
> > > to generic connector handling.
> > >
> > > Use drm_bridge_connector_init to create a connector for display
> > > pipelines that use drm_bridge.
> > >
> > > This allows splitting connector operations across multiple bridges
> > > when necessary, instead of having the last bridge in the chain
> > > creating the connector and handling all connector operations
> > > internally.
> > >
> > > Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
> >
> > Most of the code removed in that patch was actually introduced earlier
> > which feels a bit weird. Is there a reason we can't do that one first,
> > and then introduce the bridge support?
> 
> This patch adds new bridge API's which requires the driver has to
> support the bridge first.

I'm not sure what you're saying, you can definitely have a bridge
without support for a downstream bridge.

Anyway, my point is that:

> ---
> Changes for v3:
> - new patch
>
>  drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 108 +++++++------------------
>  drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h |   7 --
>  2 files changed, 27 insertions(+), 88 deletions(-)
>
> diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
> index 3cdc14daf25c..5e5d3789b3df 100644
> --- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
> +++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
> @@ -20,6 +20,7 @@
>  #include <linux/slab.h>
>
>  #include <drm/drm_atomic_helper.h>
> +#include <drm/drm_bridge_connector.h>
>  #include <drm/drm_mipi_dsi.h>
>  #include <drm/drm_of.h>
>  #include <drm/drm_panel.h>
> @@ -769,12 +770,6 @@ static void sun6i_dsi_bridge_pre_enable(struct drm_bridge *bridge)
>  	phy_set_mode(dsi->dphy, PHY_MODE_MIPI_DPHY);
>  	phy_configure(dsi->dphy, &opts);
>  	phy_power_on(dsi->dphy);
> -
> -	if (dsi->panel)
> -		drm_panel_prepare(dsi->panel);
> -
> -	if (dsi->panel_bridge)
> -		dsi->panel_bridge->funcs->pre_enable(dsi->panel_bridge);

This is added in patch 2

>  }
>
>  static void sun6i_dsi_bridge_enable(struct drm_bridge *bridge)
> @@ -793,12 +788,6 @@ static void sun6i_dsi_bridge_enable(struct drm_bridge *bridge)
>  	 * ordering on the panels I've tested it with, so I guess this
>  	 * will do for now, until that IP is better understood.
>  	 */
> -	if (dsi->panel)
> -		drm_panel_enable(dsi->panel);
> -
> -	if (dsi->panel_bridge)
> -		dsi->panel_bridge->funcs->enable(dsi->panel_bridge);
> -

This is added in patch 2

>  	sun6i_dsi_start(dsi, DSI_START_HSC);
>
>  	udelay(1000);
> @@ -812,14 +801,6 @@ static void sun6i_dsi_bridge_disable(struct drm_bridge *bridge)
>
>  	DRM_DEBUG_DRIVER("Disabling DSI output\n");
>
> -	if (dsi->panel) {
> -		drm_panel_disable(dsi->panel);
> -		drm_panel_unprepare(dsi->panel);
> -	} else if (dsi->panel_bridge) {
> -		dsi->panel_bridge->funcs->disable(dsi->panel_bridge);
> -		dsi->panel_bridge->funcs->post_disable(dsi->panel_bridge);
> -	}
> -

This is added in patch 2

>  	phy_power_off(dsi->dphy);
>  	phy_exit(dsi->dphy);
>
> @@ -828,63 +809,13 @@ static void sun6i_dsi_bridge_disable(struct drm_bridge *bridge)
>  	regulator_disable(dsi->regulator);
>  }
>
> -static int sun6i_dsi_get_modes(struct drm_connector *connector)
> -{
> -	struct sun6i_dsi *dsi = connector_to_sun6i_dsi(connector);
> -
> -	return drm_panel_get_modes(dsi->panel, connector);
> -}
> -
> -static const struct drm_connector_helper_funcs sun6i_dsi_connector_helper_funcs = {
> -	.get_modes	= sun6i_dsi_get_modes,
> -};
> -
> -static enum drm_connector_status
> -sun6i_dsi_connector_detect(struct drm_connector *connector, bool force)
> -{
> -	struct sun6i_dsi *dsi = connector_to_sun6i_dsi(connector);
> -
> -	return dsi->panel ? connector_status_connected :
> -			    connector_status_disconnected;
> -}
> -
> -static const struct drm_connector_funcs sun6i_dsi_connector_funcs = {
> -	.detect			= sun6i_dsi_connector_detect,
> -	.fill_modes		= drm_helper_probe_single_connector_modes,
> -	.destroy		= drm_connector_cleanup,
> -	.reset			= drm_atomic_helper_connector_reset,
> -	.atomic_duplicate_state	= drm_atomic_helper_connector_duplicate_state,
> -	.atomic_destroy_state	= drm_atomic_helper_connector_destroy_state,
> -};
> -
>  static int sun6i_dsi_bridge_attach(struct drm_bridge *bridge,
>  				   enum drm_bridge_attach_flags flags)
>  {
>  	struct sun6i_dsi *dsi = bridge_to_sun6i_dsi(bridge);
> -	int ret;
> -
> -	if (dsi->panel_bridge)
> -		return drm_bridge_attach(bridge->encoder, dsi->panel_bridge, NULL, 0);

This is added in patch 2

> -	if (dsi->panel) {
> -		drm_connector_helper_add(&dsi->connector,
> -					 &sun6i_dsi_connector_helper_funcs);
> -		ret = drm_connector_init(bridge->dev, &dsi->connector,
> -					 &sun6i_dsi_connector_funcs,
> -					 DRM_MODE_CONNECTOR_DSI);
> -		if (ret) {
> -			dev_err(dsi->dev, "Couldn't initialise the DSI connector\n");
> -			goto err_cleanup_connector;
> -		}
> -
> -		drm_connector_attach_encoder(&dsi->connector, &dsi->encoder);
> -	}

This has been added (through a rework) in patch 3

Surely we can do better?

Maxime
Jagan Teki March 2, 2021, 5:46 p.m. UTC | #4
On Tue, Mar 2, 2021 at 10:05 PM Maxime Ripard <maxime@cerno.tech> wrote:
>
> On Fri, Feb 26, 2021 at 10:40:24PM +0530, Jagan Teki wrote:
> > On Fri, Feb 26, 2021 at 10:27 PM Maxime Ripard <mripard@kernel.org> wrote:
> > >
> > > Hi,
> > >
> > > On Mon, Feb 15, 2021 at 01:11:01AM +0530, Jagan Teki wrote:
> > > > Use drm_panel_bridge to replace manual panel handling code.
> > > >
> > > > This simplifies the driver to allows all components in the
> > > > display pipeline to be treated as bridges, paving the way
> > > > to generic connector handling.
> > > >
> > > > Use drm_bridge_connector_init to create a connector for display
> > > > pipelines that use drm_bridge.
> > > >
> > > > This allows splitting connector operations across multiple bridges
> > > > when necessary, instead of having the last bridge in the chain
> > > > creating the connector and handling all connector operations
> > > > internally.
> > > >
> > > > Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
> > >
> > > Most of the code removed in that patch was actually introduced earlier
> > > which feels a bit weird. Is there a reason we can't do that one first,
> > > and then introduce the bridge support?
> >
> > This patch adds new bridge API's which requires the driver has to
> > support the bridge first.
>
> I'm not sure what you're saying, you can definitely have a bridge
> without support for a downstream bridge.

I understand your point. what I'm saying here is, This patch
introduces two new bridge API's

devm_drm_panel_bridge_add
drm_bridge_connector_init

In order to add these API's the driver has to support the bridge
first. All the patches before this one support bridge and this patch
introduce new APIs, ie the reason we have code removed in this patch
which has been added before.

Okay. I think I will send the next version series till bridge
conversion. Improvement patches like this can take care of later
versions and even it depends on Patch v3 5/7 which indeed require a
separate discussion. This way it makes less confusion.

Hope it's fine for you?

Jagan.

Patch

diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
index 3cdc14daf25c..5e5d3789b3df 100644
--- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
+++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
@@ -20,6 +20,7 @@ 
 #include <linux/slab.h>
 
 #include <drm/drm_atomic_helper.h>
+#include <drm/drm_bridge_connector.h>
 #include <drm/drm_mipi_dsi.h>
 #include <drm/drm_of.h>
 #include <drm/drm_panel.h>
@@ -769,12 +770,6 @@  static void sun6i_dsi_bridge_pre_enable(struct drm_bridge *bridge)
 	phy_set_mode(dsi->dphy, PHY_MODE_MIPI_DPHY);
 	phy_configure(dsi->dphy, &opts);
 	phy_power_on(dsi->dphy);
-
-	if (dsi->panel)
-		drm_panel_prepare(dsi->panel);
-
-	if (dsi->panel_bridge)
-		dsi->panel_bridge->funcs->pre_enable(dsi->panel_bridge);
 }
 
 static void sun6i_dsi_bridge_enable(struct drm_bridge *bridge)
@@ -793,12 +788,6 @@  static void sun6i_dsi_bridge_enable(struct drm_bridge *bridge)
 	 * ordering on the panels I've tested it with, so I guess this
 	 * will do for now, until that IP is better understood.
 	 */
-	if (dsi->panel)
-		drm_panel_enable(dsi->panel);
-
-	if (dsi->panel_bridge)
-		dsi->panel_bridge->funcs->enable(dsi->panel_bridge);
-
 	sun6i_dsi_start(dsi, DSI_START_HSC);
 
 	udelay(1000);
@@ -812,14 +801,6 @@  static void sun6i_dsi_bridge_disable(struct drm_bridge *bridge)
 
 	DRM_DEBUG_DRIVER("Disabling DSI output\n");
 
-	if (dsi->panel) {
-		drm_panel_disable(dsi->panel);
-		drm_panel_unprepare(dsi->panel);
-	} else if (dsi->panel_bridge) {
-		dsi->panel_bridge->funcs->disable(dsi->panel_bridge);
-		dsi->panel_bridge->funcs->post_disable(dsi->panel_bridge);
-	}
-
 	phy_power_off(dsi->dphy);
 	phy_exit(dsi->dphy);
 
@@ -828,63 +809,13 @@  static void sun6i_dsi_bridge_disable(struct drm_bridge *bridge)
 	regulator_disable(dsi->regulator);
 }
 
-static int sun6i_dsi_get_modes(struct drm_connector *connector)
-{
-	struct sun6i_dsi *dsi = connector_to_sun6i_dsi(connector);
-
-	return drm_panel_get_modes(dsi->panel, connector);
-}
-
-static const struct drm_connector_helper_funcs sun6i_dsi_connector_helper_funcs = {
-	.get_modes	= sun6i_dsi_get_modes,
-};
-
-static enum drm_connector_status
-sun6i_dsi_connector_detect(struct drm_connector *connector, bool force)
-{
-	struct sun6i_dsi *dsi = connector_to_sun6i_dsi(connector);
-
-	return dsi->panel ? connector_status_connected :
-			    connector_status_disconnected;
-}
-
-static const struct drm_connector_funcs sun6i_dsi_connector_funcs = {
-	.detect			= sun6i_dsi_connector_detect,
-	.fill_modes		= drm_helper_probe_single_connector_modes,
-	.destroy		= drm_connector_cleanup,
-	.reset			= drm_atomic_helper_connector_reset,
-	.atomic_duplicate_state	= drm_atomic_helper_connector_duplicate_state,
-	.atomic_destroy_state	= drm_atomic_helper_connector_destroy_state,
-};
-
 static int sun6i_dsi_bridge_attach(struct drm_bridge *bridge,
 				   enum drm_bridge_attach_flags flags)
 {
 	struct sun6i_dsi *dsi = bridge_to_sun6i_dsi(bridge);
-	int ret;
-
-	if (dsi->panel_bridge)
-		return drm_bridge_attach(bridge->encoder, dsi->panel_bridge, NULL, 0);
-
-	if (dsi->panel) {
-		drm_connector_helper_add(&dsi->connector,
-					 &sun6i_dsi_connector_helper_funcs);
-		ret = drm_connector_init(bridge->dev, &dsi->connector,
-					 &sun6i_dsi_connector_funcs,
-					 DRM_MODE_CONNECTOR_DSI);
-		if (ret) {
-			dev_err(dsi->dev, "Couldn't initialise the DSI connector\n");
-			goto err_cleanup_connector;
-		}
-
-		drm_connector_attach_encoder(&dsi->connector, &dsi->encoder);
-	}
-
-	return 0;
 
-err_cleanup_connector:
-	drm_encoder_cleanup(&dsi->encoder);
-	return ret;
+	return drm_bridge_attach(bridge->encoder, dsi->panel_bridge,
+				 &dsi->bridge, flags);
 }
 
 static const struct drm_bridge_funcs sun6i_dsi_bridge_funcs = {
@@ -1010,17 +941,24 @@  static int sun6i_dsi_attach(struct mipi_dsi_host *host,
 			    struct mipi_dsi_device *device)
 {
 	struct sun6i_dsi *dsi = host_to_sun6i_dsi(host);
+	struct drm_panel *panel;
 	int ret;
 
 	ret = drm_of_find_panel_or_bridge(dsi->dev->of_node, 0, 0,
-					  &dsi->panel, &dsi->panel_bridge);
+					  &panel, &dsi->panel_bridge);
 	if (ret)
 		return ret;
 
+	if (panel) {
+		dsi->panel_bridge = devm_drm_panel_bridge_add(dsi->dev, panel);
+		if (IS_ERR(dsi->panel_bridge))
+			return PTR_ERR(dsi->panel_bridge);
+	}
+
 	dsi->device = device;
 
-	dev_info(host->dev, "Attached %s %s\n",
-		 device->name, dsi->panel ? "panel" : "bridge");
+	dev_info(host->dev,
+		 "Attached %s %s\n", device->name, panel ? "panel" : "bridge");
 
 	return 0;
 }
@@ -1030,7 +968,6 @@  static int sun6i_dsi_detach(struct mipi_dsi_host *host,
 {
 	struct sun6i_dsi *dsi = host_to_sun6i_dsi(host);
 
-	dsi->panel = NULL;
 	dsi->panel_bridge = NULL;
 	dsi->device = NULL;
 
@@ -1098,6 +1035,7 @@  static int sun6i_dsi_bind(struct device *dev, struct device *master,
 {
 	struct drm_device *drm = data;
 	struct sun6i_dsi *dsi = dev_get_drvdata(dev);
+	struct drm_connector *connector;
 	int ret;
 
 	ret = drm_simple_encoder_init(drm, &dsi->encoder,
@@ -1108,15 +1046,23 @@  static int sun6i_dsi_bind(struct device *dev, struct device *master,
 	}
 	dsi->encoder.possible_crtcs = BIT(0);
 
-	ret = drm_bridge_attach(&dsi->encoder, &dsi->bridge, NULL, 0);
-	if (ret) {
-		dev_err(dsi->dev, "Couldn't attach drm bridge\n");
-		goto err_cleanup_connector;
+	ret = drm_bridge_attach(&dsi->encoder, &dsi->bridge, NULL,
+				DRM_BRIDGE_ATTACH_NO_CONNECTOR);
+	if (ret)
+		goto err_cleanup_encoder;
+
+	connector = drm_bridge_connector_init(drm, &dsi->encoder);
+	if (IS_ERR(connector)) {
+		DRM_ERROR("Unable to create bridge connector\n");
+		ret = PTR_ERR(connector);
+		goto err_cleanup_encoder;
 	}
 
+	drm_connector_attach_encoder(connector, &dsi->encoder);
+
 	return 0;
 
-err_cleanup_connector:
+err_cleanup_encoder:
 	drm_encoder_cleanup(&dsi->encoder);
 	return ret;
 }
diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h
index 5e70666089ad..91ea95326ed4 100644
--- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h
+++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h
@@ -17,7 +17,6 @@ 
 
 struct sun6i_dsi {
 	struct drm_bridge	bridge;
-	struct drm_connector	connector;
 	struct drm_encoder	encoder;
 	struct mipi_dsi_host	host;
 
@@ -30,7 +29,6 @@  struct sun6i_dsi {
 
 	struct device		*dev;
 	struct mipi_dsi_device	*device;
-	struct drm_panel	*panel;
 	struct drm_bridge	*panel_bridge;
 };
 
@@ -44,11 +42,6 @@  static inline struct sun6i_dsi *bridge_to_sun6i_dsi(struct drm_bridge *bridge)
 	return container_of(bridge, struct sun6i_dsi, bridge);
 }
 
-static inline struct sun6i_dsi *connector_to_sun6i_dsi(struct drm_connector *connector)
-{
-	return container_of(connector, struct sun6i_dsi, connector);
-};
-
 static inline struct sun6i_dsi *encoder_to_sun6i_dsi(const struct drm_encoder *encoder)
 {
 	return container_of(encoder, struct sun6i_dsi, encoder);