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From: Eric Anholt <eric@anholt.net>
To: dri-devel@lists.freedesktop.org
Cc: linux-kernel@vger.kernel.org,
	Yannick Fertre <yannick.fertre@st.com>,
	Eric Anholt <eric@anholt.net>
Subject: [PATCH 2/2] drm/vc4: Switch to using the panel-bridge layer, and support bridges.
Date: Thu, 27 Apr 2017 09:36:01 -0700	[thread overview]
Message-ID: <20170427163601.7313-2-eric@anholt.net> (raw)
In-Reply-To: <20170427163601.7313-1-eric@anholt.net>

The newer version of the RPi panel driver is going to be a combination
of a bridge and a panel, but we should also support panels without a
bridge, so the panel-bridge layer lets us do that cleanly.

Signed-off-by: Eric Anholt <eric@anholt.net>
---
 drivers/gpu/drm/vc4/Kconfig   |   2 +-
 drivers/gpu/drm/vc4/vc4_dsi.c | 158 +++++++-----------------------------------
 2 files changed, 26 insertions(+), 134 deletions(-)

diff --git a/drivers/gpu/drm/vc4/Kconfig b/drivers/gpu/drm/vc4/Kconfig
index 973b4203c0b2..118def67c9a9 100644
--- a/drivers/gpu/drm/vc4/Kconfig
+++ b/drivers/gpu/drm/vc4/Kconfig
@@ -7,7 +7,7 @@ config DRM_VC4
 	select DRM_KMS_HELPER
 	select DRM_KMS_CMA_HELPER
 	select DRM_GEM_CMA_HELPER
-	select DRM_PANEL
+	select DRM_PANEL_BRIDGE
 	select SND_PCM
 	select SND_PCM_ELD
 	select SND_SOC_GENERIC_DMAENGINE_PCM
diff --git a/drivers/gpu/drm/vc4/vc4_dsi.c b/drivers/gpu/drm/vc4/vc4_dsi.c
index deba62008fd0..a279188e310c 100644
--- a/drivers/gpu/drm/vc4/vc4_dsi.c
+++ b/drivers/gpu/drm/vc4/vc4_dsi.c
@@ -503,8 +503,8 @@ struct vc4_dsi {
 
 	struct mipi_dsi_host dsi_host;
 	struct drm_encoder *encoder;
-	struct drm_connector *connector;
-	struct drm_panel *panel;
+	struct drm_bridge *bridge;
+	bool is_panel_bridge;
 
 	void __iomem *regs;
 
@@ -604,18 +604,6 @@ to_vc4_dsi_encoder(struct drm_encoder *encoder)
 	return container_of(encoder, struct vc4_dsi_encoder, base.base);
 }
 
-/* VC4 DSI connector KMS struct */
-struct vc4_dsi_connector {
-	struct drm_connector base;
-	struct vc4_dsi *dsi;
-};
-
-static inline struct vc4_dsi_connector *
-to_vc4_dsi_connector(struct drm_connector *connector)
-{
-	return container_of(connector, struct vc4_dsi_connector, base);
-}
-
 #define DSI_REG(reg) { reg, #reg }
 static const struct {
 	u32 reg;
@@ -723,79 +711,6 @@ int vc4_dsi_debugfs_regs(struct seq_file *m, void *unused)
 }
 #endif
 
-static enum drm_connector_status
-vc4_dsi_connector_detect(struct drm_connector *connector, bool force)
-{
-	struct vc4_dsi_connector *vc4_connector =
-		to_vc4_dsi_connector(connector);
-	struct vc4_dsi *dsi = vc4_connector->dsi;
-
-	if (dsi->panel)
-		return connector_status_connected;
-	else
-		return connector_status_disconnected;
-}
-
-static void vc4_dsi_connector_destroy(struct drm_connector *connector)
-{
-	drm_connector_unregister(connector);
-	drm_connector_cleanup(connector);
-}
-
-static int vc4_dsi_connector_get_modes(struct drm_connector *connector)
-{
-	struct vc4_dsi_connector *vc4_connector =
-		to_vc4_dsi_connector(connector);
-	struct vc4_dsi *dsi = vc4_connector->dsi;
-
-	if (dsi->panel)
-		return drm_panel_get_modes(dsi->panel);
-
-	return 0;
-}
-
-static const struct drm_connector_funcs vc4_dsi_connector_funcs = {
-	.dpms = drm_atomic_helper_connector_dpms,
-	.detect = vc4_dsi_connector_detect,
-	.fill_modes = drm_helper_probe_single_connector_modes,
-	.destroy = vc4_dsi_connector_destroy,
-	.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 const struct drm_connector_helper_funcs vc4_dsi_connector_helper_funcs = {
-	.get_modes = vc4_dsi_connector_get_modes,
-};
-
-static struct drm_connector *vc4_dsi_connector_init(struct drm_device *dev,
-						    struct vc4_dsi *dsi)
-{
-	struct drm_connector *connector;
-	struct vc4_dsi_connector *dsi_connector;
-
-	dsi_connector = devm_kzalloc(dev->dev, sizeof(*dsi_connector),
-				     GFP_KERNEL);
-	if (!dsi_connector)
-		return ERR_PTR(-ENOMEM);
-
-	connector = &dsi_connector->base;
-
-	dsi_connector->dsi = dsi;
-
-	drm_connector_init(dev, connector, &vc4_dsi_connector_funcs,
-			   DRM_MODE_CONNECTOR_DSI);
-	drm_connector_helper_add(connector, &vc4_dsi_connector_helper_funcs);
-
-	connector->polled = 0;
-	connector->interlace_allowed = 0;
-	connector->doublescan_allowed = 0;
-
-	drm_mode_connector_attach_encoder(connector, dsi->encoder);
-
-	return connector;
-}
-
 static void vc4_dsi_encoder_destroy(struct drm_encoder *encoder)
 {
 	drm_encoder_cleanup(encoder);
@@ -893,12 +808,8 @@ static void vc4_dsi_encoder_disable(struct drm_encoder *encoder)
 	struct vc4_dsi *dsi = vc4_encoder->dsi;
 	struct device *dev = &dsi->pdev->dev;
 
-	drm_panel_disable(dsi->panel);
-
 	vc4_dsi_ulps(dsi, true);
 
-	drm_panel_unprepare(dsi->panel);
-
 	clk_disable_unprepare(dsi->pll_phy_clock);
 	clk_disable_unprepare(dsi->escape_clock);
 	clk_disable_unprepare(dsi->pixel_clock);
@@ -929,12 +840,6 @@ static void vc4_dsi_encoder_enable(struct drm_encoder *encoder)
 		return;
 	}
 
-	ret = drm_panel_prepare(dsi->panel);
-	if (ret) {
-		DRM_ERROR("Panel failed to prepare\n");
-		return;
-	}
-
 	if (debug_dump_regs) {
 		DRM_INFO("DSI regs before:\n");
 		vc4_dsi_dump_regs(dsi);
@@ -1184,13 +1089,6 @@ static void vc4_dsi_encoder_enable(struct drm_encoder *encoder)
 		DRM_INFO("DSI regs after:\n");
 		vc4_dsi_dump_regs(dsi);
 	}
-
-	ret = drm_panel_enable(dsi->panel);
-	if (ret) {
-		DRM_ERROR("Panel failed to enable\n");
-		drm_panel_unprepare(dsi->panel);
-		return;
-	}
 }
 
 static ssize_t vc4_dsi_host_transfer(struct mipi_dsi_host *host,
@@ -1366,15 +1264,28 @@ static int vc4_dsi_host_attach(struct mipi_dsi_host *host,
 		return 0;
 	}
 
-	dsi->panel = of_drm_find_panel(device->dev.of_node);
-	if (!dsi->panel)
-		return 0;
+	dsi->bridge = of_drm_find_bridge(device->dev.of_node);
+	if (!dsi->bridge) {
+		struct drm_panel *panel =
+			of_drm_find_panel(device->dev.of_node);
+
+		dsi->bridge = drm_panel_bridge_add(&device->dev,
+						   panel,
+						   DRM_MODE_CONNECTOR_DSI);
+		if (IS_ERR(dsi->bridge)) {
+			ret = PTR_ERR(dsi->bridge);
+			dsi->bridge = NULL;
+			return ret;
+		}
+		dsi->is_panel_bridge = true;
+	}
 
-	ret = drm_panel_attach(dsi->panel, dsi->connector);
-	if (ret != 0)
+	ret = drm_bridge_attach(dsi->encoder, dsi->bridge, NULL);
+	if (ret) {
+		if (dsi->is_panel_bridge)
+			drm_panel_bridge_remove(&device->dev, dsi->bridge);
 		return ret;
-
-	drm_helper_hpd_irq_event(dsi->connector->dev);
+	}
 
 	return 0;
 }
@@ -1384,16 +1295,8 @@ static int vc4_dsi_host_detach(struct mipi_dsi_host *host,
 {
 	struct vc4_dsi *dsi = host_to_dsi(host);
 
-	if (dsi->panel) {
-		int ret = drm_panel_detach(dsi->panel);
-
-		if (ret)
-			return ret;
-
-		dsi->panel = NULL;
-
-		drm_helper_hpd_irq_event(dsi->connector->dev);
-	}
+	if (dsi->is_panel_bridge)
+		drm_panel_bridge_remove(&device->dev, dsi->bridge);
 
 	return 0;
 }
@@ -1658,12 +1561,6 @@ static int vc4_dsi_bind(struct device *dev, struct device *master, void *data)
 			 DRM_MODE_ENCODER_DSI, NULL);
 	drm_encoder_helper_add(dsi->encoder, &vc4_dsi_encoder_helper_funcs);
 
-	dsi->connector = vc4_dsi_connector_init(drm, dsi);
-	if (IS_ERR(dsi->connector)) {
-		ret = PTR_ERR(dsi->connector);
-		goto err_destroy_encoder;
-	}
-
 	dsi->dsi_host.ops = &vc4_dsi_host_ops;
 	dsi->dsi_host.dev = dev;
 
@@ -1674,11 +1571,6 @@ static int vc4_dsi_bind(struct device *dev, struct device *master, void *data)
 	pm_runtime_enable(dev);
 
 	return 0;
-
-err_destroy_encoder:
-	vc4_dsi_encoder_destroy(dsi->encoder);
-
-	return ret;
 }
 
 static void vc4_dsi_unbind(struct device *dev, struct device *master,
@@ -1690,7 +1582,7 @@ static void vc4_dsi_unbind(struct device *dev, struct device *master,
 
 	pm_runtime_disable(dev);
 
-	vc4_dsi_connector_destroy(dsi->connector);
+	drm_bridge_remove(dsi->bridge);
 	vc4_dsi_encoder_destroy(dsi->encoder);
 
 	mipi_dsi_host_unregister(&dsi->dsi_host);
-- 
2.11.0

WARNING: multiple messages have this Message-ID (diff)
From: Eric Anholt <eric@anholt.net>
To: dri-devel@lists.freedesktop.org
Cc: Yannick Fertre <yannick.fertre@st.com>, linux-kernel@vger.kernel.org
Subject: [PATCH 2/2] drm/vc4: Switch to using the panel-bridge layer, and support bridges.
Date: Thu, 27 Apr 2017 09:36:01 -0700	[thread overview]
Message-ID: <20170427163601.7313-2-eric@anholt.net> (raw)
In-Reply-To: <20170427163601.7313-1-eric@anholt.net>

The newer version of the RPi panel driver is going to be a combination
of a bridge and a panel, but we should also support panels without a
bridge, so the panel-bridge layer lets us do that cleanly.

Signed-off-by: Eric Anholt <eric@anholt.net>
---
 drivers/gpu/drm/vc4/Kconfig   |   2 +-
 drivers/gpu/drm/vc4/vc4_dsi.c | 158 +++++++-----------------------------------
 2 files changed, 26 insertions(+), 134 deletions(-)

diff --git a/drivers/gpu/drm/vc4/Kconfig b/drivers/gpu/drm/vc4/Kconfig
index 973b4203c0b2..118def67c9a9 100644
--- a/drivers/gpu/drm/vc4/Kconfig
+++ b/drivers/gpu/drm/vc4/Kconfig
@@ -7,7 +7,7 @@ config DRM_VC4
 	select DRM_KMS_HELPER
 	select DRM_KMS_CMA_HELPER
 	select DRM_GEM_CMA_HELPER
-	select DRM_PANEL
+	select DRM_PANEL_BRIDGE
 	select SND_PCM
 	select SND_PCM_ELD
 	select SND_SOC_GENERIC_DMAENGINE_PCM
diff --git a/drivers/gpu/drm/vc4/vc4_dsi.c b/drivers/gpu/drm/vc4/vc4_dsi.c
index deba62008fd0..a279188e310c 100644
--- a/drivers/gpu/drm/vc4/vc4_dsi.c
+++ b/drivers/gpu/drm/vc4/vc4_dsi.c
@@ -503,8 +503,8 @@ struct vc4_dsi {
 
 	struct mipi_dsi_host dsi_host;
 	struct drm_encoder *encoder;
-	struct drm_connector *connector;
-	struct drm_panel *panel;
+	struct drm_bridge *bridge;
+	bool is_panel_bridge;
 
 	void __iomem *regs;
 
@@ -604,18 +604,6 @@ to_vc4_dsi_encoder(struct drm_encoder *encoder)
 	return container_of(encoder, struct vc4_dsi_encoder, base.base);
 }
 
-/* VC4 DSI connector KMS struct */
-struct vc4_dsi_connector {
-	struct drm_connector base;
-	struct vc4_dsi *dsi;
-};
-
-static inline struct vc4_dsi_connector *
-to_vc4_dsi_connector(struct drm_connector *connector)
-{
-	return container_of(connector, struct vc4_dsi_connector, base);
-}
-
 #define DSI_REG(reg) { reg, #reg }
 static const struct {
 	u32 reg;
@@ -723,79 +711,6 @@ int vc4_dsi_debugfs_regs(struct seq_file *m, void *unused)
 }
 #endif
 
-static enum drm_connector_status
-vc4_dsi_connector_detect(struct drm_connector *connector, bool force)
-{
-	struct vc4_dsi_connector *vc4_connector =
-		to_vc4_dsi_connector(connector);
-	struct vc4_dsi *dsi = vc4_connector->dsi;
-
-	if (dsi->panel)
-		return connector_status_connected;
-	else
-		return connector_status_disconnected;
-}
-
-static void vc4_dsi_connector_destroy(struct drm_connector *connector)
-{
-	drm_connector_unregister(connector);
-	drm_connector_cleanup(connector);
-}
-
-static int vc4_dsi_connector_get_modes(struct drm_connector *connector)
-{
-	struct vc4_dsi_connector *vc4_connector =
-		to_vc4_dsi_connector(connector);
-	struct vc4_dsi *dsi = vc4_connector->dsi;
-
-	if (dsi->panel)
-		return drm_panel_get_modes(dsi->panel);
-
-	return 0;
-}
-
-static const struct drm_connector_funcs vc4_dsi_connector_funcs = {
-	.dpms = drm_atomic_helper_connector_dpms,
-	.detect = vc4_dsi_connector_detect,
-	.fill_modes = drm_helper_probe_single_connector_modes,
-	.destroy = vc4_dsi_connector_destroy,
-	.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 const struct drm_connector_helper_funcs vc4_dsi_connector_helper_funcs = {
-	.get_modes = vc4_dsi_connector_get_modes,
-};
-
-static struct drm_connector *vc4_dsi_connector_init(struct drm_device *dev,
-						    struct vc4_dsi *dsi)
-{
-	struct drm_connector *connector;
-	struct vc4_dsi_connector *dsi_connector;
-
-	dsi_connector = devm_kzalloc(dev->dev, sizeof(*dsi_connector),
-				     GFP_KERNEL);
-	if (!dsi_connector)
-		return ERR_PTR(-ENOMEM);
-
-	connector = &dsi_connector->base;
-
-	dsi_connector->dsi = dsi;
-
-	drm_connector_init(dev, connector, &vc4_dsi_connector_funcs,
-			   DRM_MODE_CONNECTOR_DSI);
-	drm_connector_helper_add(connector, &vc4_dsi_connector_helper_funcs);
-
-	connector->polled = 0;
-	connector->interlace_allowed = 0;
-	connector->doublescan_allowed = 0;
-
-	drm_mode_connector_attach_encoder(connector, dsi->encoder);
-
-	return connector;
-}
-
 static void vc4_dsi_encoder_destroy(struct drm_encoder *encoder)
 {
 	drm_encoder_cleanup(encoder);
@@ -893,12 +808,8 @@ static void vc4_dsi_encoder_disable(struct drm_encoder *encoder)
 	struct vc4_dsi *dsi = vc4_encoder->dsi;
 	struct device *dev = &dsi->pdev->dev;
 
-	drm_panel_disable(dsi->panel);
-
 	vc4_dsi_ulps(dsi, true);
 
-	drm_panel_unprepare(dsi->panel);
-
 	clk_disable_unprepare(dsi->pll_phy_clock);
 	clk_disable_unprepare(dsi->escape_clock);
 	clk_disable_unprepare(dsi->pixel_clock);
@@ -929,12 +840,6 @@ static void vc4_dsi_encoder_enable(struct drm_encoder *encoder)
 		return;
 	}
 
-	ret = drm_panel_prepare(dsi->panel);
-	if (ret) {
-		DRM_ERROR("Panel failed to prepare\n");
-		return;
-	}
-
 	if (debug_dump_regs) {
 		DRM_INFO("DSI regs before:\n");
 		vc4_dsi_dump_regs(dsi);
@@ -1184,13 +1089,6 @@ static void vc4_dsi_encoder_enable(struct drm_encoder *encoder)
 		DRM_INFO("DSI regs after:\n");
 		vc4_dsi_dump_regs(dsi);
 	}
-
-	ret = drm_panel_enable(dsi->panel);
-	if (ret) {
-		DRM_ERROR("Panel failed to enable\n");
-		drm_panel_unprepare(dsi->panel);
-		return;
-	}
 }
 
 static ssize_t vc4_dsi_host_transfer(struct mipi_dsi_host *host,
@@ -1366,15 +1264,28 @@ static int vc4_dsi_host_attach(struct mipi_dsi_host *host,
 		return 0;
 	}
 
-	dsi->panel = of_drm_find_panel(device->dev.of_node);
-	if (!dsi->panel)
-		return 0;
+	dsi->bridge = of_drm_find_bridge(device->dev.of_node);
+	if (!dsi->bridge) {
+		struct drm_panel *panel =
+			of_drm_find_panel(device->dev.of_node);
+
+		dsi->bridge = drm_panel_bridge_add(&device->dev,
+						   panel,
+						   DRM_MODE_CONNECTOR_DSI);
+		if (IS_ERR(dsi->bridge)) {
+			ret = PTR_ERR(dsi->bridge);
+			dsi->bridge = NULL;
+			return ret;
+		}
+		dsi->is_panel_bridge = true;
+	}
 
-	ret = drm_panel_attach(dsi->panel, dsi->connector);
-	if (ret != 0)
+	ret = drm_bridge_attach(dsi->encoder, dsi->bridge, NULL);
+	if (ret) {
+		if (dsi->is_panel_bridge)
+			drm_panel_bridge_remove(&device->dev, dsi->bridge);
 		return ret;
-
-	drm_helper_hpd_irq_event(dsi->connector->dev);
+	}
 
 	return 0;
 }
@@ -1384,16 +1295,8 @@ static int vc4_dsi_host_detach(struct mipi_dsi_host *host,
 {
 	struct vc4_dsi *dsi = host_to_dsi(host);
 
-	if (dsi->panel) {
-		int ret = drm_panel_detach(dsi->panel);
-
-		if (ret)
-			return ret;
-
-		dsi->panel = NULL;
-
-		drm_helper_hpd_irq_event(dsi->connector->dev);
-	}
+	if (dsi->is_panel_bridge)
+		drm_panel_bridge_remove(&device->dev, dsi->bridge);
 
 	return 0;
 }
@@ -1658,12 +1561,6 @@ static int vc4_dsi_bind(struct device *dev, struct device *master, void *data)
 			 DRM_MODE_ENCODER_DSI, NULL);
 	drm_encoder_helper_add(dsi->encoder, &vc4_dsi_encoder_helper_funcs);
 
-	dsi->connector = vc4_dsi_connector_init(drm, dsi);
-	if (IS_ERR(dsi->connector)) {
-		ret = PTR_ERR(dsi->connector);
-		goto err_destroy_encoder;
-	}
-
 	dsi->dsi_host.ops = &vc4_dsi_host_ops;
 	dsi->dsi_host.dev = dev;
 
@@ -1674,11 +1571,6 @@ static int vc4_dsi_bind(struct device *dev, struct device *master, void *data)
 	pm_runtime_enable(dev);
 
 	return 0;
-
-err_destroy_encoder:
-	vc4_dsi_encoder_destroy(dsi->encoder);
-
-	return ret;
 }
 
 static void vc4_dsi_unbind(struct device *dev, struct device *master,
@@ -1690,7 +1582,7 @@ static void vc4_dsi_unbind(struct device *dev, struct device *master,
 
 	pm_runtime_disable(dev);
 
-	vc4_dsi_connector_destroy(dsi->connector);
+	drm_bridge_remove(dsi->bridge);
 	vc4_dsi_encoder_destroy(dsi->encoder);
 
 	mipi_dsi_host_unregister(&dsi->dsi_host);
-- 
2.11.0

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  reply	other threads:[~2017-04-27 16:36 UTC|newest]

Thread overview: 32+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-04-27 16:36 [PATCH 1/2] drm/bridge: Refactor out the panel wrapper from the lvds-encoder bridge Eric Anholt
2017-04-27 16:36 ` Eric Anholt
2017-04-27 16:36 ` Eric Anholt [this message]
2017-04-27 16:36   ` [PATCH 2/2] drm/vc4: Switch to using the panel-bridge layer, and support bridges Eric Anholt
2017-04-27 17:27 ` [PATCH 1/2] drm/bridge: Refactor out the panel wrapper from the lvds-encoder bridge Eric Anholt
2017-04-27 17:27   ` Eric Anholt
2017-05-03  9:23 ` Archit Taneja
2017-05-03  9:23   ` Archit Taneja
2017-05-03  9:32   ` Laurent Pinchart
2017-05-03  9:32     ` Laurent Pinchart
2017-05-03  9:32   ` Daniel Vetter
2017-05-03  9:32     ` Daniel Vetter
2017-05-03  9:36     ` Laurent Pinchart
2017-05-03  9:36       ` Laurent Pinchart
2017-05-03 14:28       ` Daniel Vetter
2017-05-03 14:28         ` Daniel Vetter
2017-05-03 14:44         ` Laurent Pinchart
2017-05-03 14:44           ` Laurent Pinchart
2017-05-03 16:17           ` Eric Anholt
2017-05-03 16:17             ` Eric Anholt
2017-05-04  5:44             ` Daniel Vetter
2017-05-04  5:44               ` Daniel Vetter
2017-05-04 12:35               ` Thierry Reding
2017-05-04 12:35                 ` Thierry Reding
2017-05-05  6:22                 ` Andrzej Hajda
2017-05-05  6:22                   ` Andrzej Hajda
2017-05-03 16:30   ` Eric Anholt
2017-05-03 16:30     ` Eric Anholt
2017-05-04  8:58     ` Archit Taneja
2017-05-04  8:58       ` Archit Taneja
2017-05-03  9:36 ` Daniel Vetter
2017-05-03  9:36   ` Daniel Vetter

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