So that each element in the chain can easily access its predecessor.
This will be needed to support bus format negotiation between elements
of the bridge chain.
Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxx>
Reviewed-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
---
Changes in v4:
* Simplify the drm_bridge_attach() logic
* Fix list iteration bugs
* Patch VC4 and Exynos DSI drivers to match core changes
* Add R-bs
Changes in v3:
* None
Changes in v2:
* Adjust things to the "dummy encoder bridge" change (patch 2 in this
series)
---
drivers/gpu/drm/drm_bridge.c | 171 +++++++++++++++---------
drivers/gpu/drm/drm_encoder.c | 16 +--
drivers/gpu/drm/exynos/exynos_drm_dsi.c | 5 +-
drivers/gpu/drm/vc4/vc4_dsi.c | 10 +-
include/drm/drm_bridge.h | 12 +-
include/drm/drm_encoder.h | 7 +-
6 files changed, 143 insertions(+), 78 deletions(-)
diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c
index 54c874493c57..b6517b4fa3d1 100644
--- a/drivers/gpu/drm/drm_bridge.c
+++ b/drivers/gpu/drm/drm_bridge.c
@@ -55,7 +55,7 @@
* just provide additional hooks to get the desired output at the end of the
* encoder chain.
*
- * Bridges can also be chained up using the &drm_bridge.next pointer.
+ * Bridges can also be chained up using the &drm_bridge.chain_node field.
*
* Both legacy CRTC helpers and the new atomic modeset helpers support bridges.
*/
@@ -128,20 +128,21 @@ int drm_bridge_attach(struct drm_encoder *encoder, struct drm_bridge *bridge,
bridge->dev = encoder->dev;
bridge->encoder = encoder;
+ if (previous)
+ list_add(&bridge->chain_node, &previous->chain_node);
+ else
+ list_add(&bridge->chain_node, &encoder->bridge_chain);
+
if (bridge->funcs->attach) {
ret = bridge->funcs->attach(bridge);
if (ret < 0) {
+ list_del(&bridge->chain_node);
bridge->dev = NULL;
bridge->encoder = NULL;
return ret;
}
}
- if (previous)
- previous->next = bridge;
- else
- encoder->bridge = bridge;
-
return 0;
}
EXPORT_SYMBOL(drm_bridge_attach);
@@ -157,6 +158,7 @@ void drm_bridge_detach(struct drm_bridge *bridge)
if (bridge->funcs->detach)
bridge->funcs->detach(bridge);
+ list_del(&bridge->chain_node);
bridge->dev = NULL;
}
@@ -190,18 +192,21 @@ bool drm_bridge_chain_mode_fixup(struct drm_bridge *bridge,
const struct drm_display_mode *mode,
struct drm_display_mode *adjusted_mode)
{
- bool ret = true;
+ struct drm_encoder *encoder;
if (!bridge)
return true;
- if (bridge->funcs->mode_fixup)
- ret = bridge->funcs->mode_fixup(bridge, mode, adjusted_mode);
+ encoder = bridge->encoder;
+ list_for_each_entry_from(bridge, &encoder->bridge_chain, chain_node) {
+ if (!bridge->funcs->mode_fixup)
+ continue;
- ret = ret && drm_bridge_chain_mode_fixup(bridge->next, mode,
- adjusted_mode);
+ if (!bridge->funcs->mode_fixup(bridge, mode, adjusted_mode))
+ return false;
+ }
- return ret;
+ return true;
}
EXPORT_SYMBOL(drm_bridge_chain_mode_fixup);
@@ -224,18 +229,24 @@ enum drm_mode_status
drm_bridge_chain_mode_valid(struct drm_bridge *bridge,
const struct drm_display_mode *mode)
{
- enum drm_mode_status ret = MODE_OK;
+ struct drm_encoder *encoder;
if (!bridge)
- return ret;
+ return MODE_OK;
- if (bridge->funcs->mode_valid)
- ret = bridge->funcs->mode_valid(bridge, mode);
+ encoder = bridge->encoder;
+ list_for_each_entry_from(bridge, &encoder->bridge_chain, chain_node) {
+ enum drm_mode_status ret;
+
+ if (!bridge->funcs->mode_valid)
+ continue;
- if (ret != MODE_OK)
- return ret;
+ ret = bridge->funcs->mode_valid(bridge, mode);
+ if (ret != MODE_OK)
+ return ret;
+ }
- return drm_bridge_chain_mode_valid(bridge->next, mode);
+ return MODE_OK;
}
EXPORT_SYMBOL(drm_bridge_chain_mode_valid);
@@ -251,13 +262,20 @@ EXPORT_SYMBOL(drm_bridge_chain_mode_valid);
*/
void drm_bridge_chain_disable(struct drm_bridge *bridge)
{
+ struct drm_encoder *encoder;
+ struct drm_bridge *iter;
+
if (!bridge)
return;
- drm_bridge_chain_disable(bridge->next);
+ encoder = bridge->encoder;
+ list_for_each_entry_reverse(iter, &encoder->bridge_chain, chain_node) {
+ if (iter->funcs->disable)
+ iter->funcs->disable(iter);
- if (bridge->funcs->disable)
- bridge->funcs->disable(bridge);
+ if (iter == bridge)
+ break;
+ }
}
EXPORT_SYMBOL(drm_bridge_chain_disable);
@@ -274,13 +292,16 @@ EXPORT_SYMBOL(drm_bridge_chain_disable);
*/
void drm_bridge_chain_post_disable(struct drm_bridge *bridge)
{
+ struct drm_encoder *encoder;
+
if (!bridge)
return;
- if (bridge->funcs->post_disable)
- bridge->funcs->post_disable(bridge);
-
- drm_bridge_chain_post_disable(bridge->next);
+ encoder = bridge->encoder;
+ list_for_each_entry_from(bridge, &encoder->bridge_chain, chain_node) {
+ if (bridge->funcs->post_disable)
+ bridge->funcs->post_disable(bridge);
+ }
}
EXPORT_SYMBOL(drm_bridge_chain_post_disable);
@@ -300,13 +321,16 @@ void drm_bridge_chain_mode_set(struct drm_bridge *bridge,
const struct drm_display_mode *mode,
const struct drm_display_mode *adjusted_mode)
{
+ struct drm_encoder *encoder;
+
if (!bridge)
return;
- if (bridge->funcs->mode_set)
- bridge->funcs->mode_set(bridge, mode, adjusted_mode);
-
- drm_bridge_chain_mode_set(bridge->next, mode, adjusted_mode);
+ encoder = bridge->encoder;
+ list_for_each_entry_from(bridge, &encoder->bridge_chain, chain_node) {
+ if (bridge->funcs->mode_set)
+ bridge->funcs->mode_set(bridge, mode, adjusted_mode);
+ }
}
EXPORT_SYMBOL(drm_bridge_chain_mode_set);
@@ -323,13 +347,17 @@ EXPORT_SYMBOL(drm_bridge_chain_mode_set);
*/
void drm_bridge_chain_pre_enable(struct drm_bridge *bridge)
{
+ struct drm_encoder *encoder;
+ struct drm_bridge *iter;
+
if (!bridge)
return;
- drm_bridge_chain_pre_enable(bridge->next);
-
- if (bridge->funcs->pre_enable)
- bridge->funcs->pre_enable(bridge);
+ encoder = bridge->encoder;
+ list_for_each_entry_reverse(iter, &encoder->bridge_chain, chain_node) {
+ if (iter->funcs->pre_enable)
+ iter->funcs->pre_enable(iter);
+ }
}
EXPORT_SYMBOL(drm_bridge_chain_pre_enable);
@@ -345,13 +373,16 @@ EXPORT_SYMBOL(drm_bridge_chain_pre_enable);
*/
void drm_bridge_chain_enable(struct drm_bridge *bridge)
{
+ struct drm_encoder *encoder;
+
if (!bridge)
return;
- if (bridge->funcs->enable)
- bridge->funcs->enable(bridge);
-
- drm_bridge_chain_enable(bridge->next);
+ encoder = bridge->encoder;
+ list_for_each_entry_from(bridge, &encoder->bridge_chain, chain_node) {
+ if (bridge->funcs->enable)
+ bridge->funcs->enable(bridge);
+ }
}
EXPORT_SYMBOL(drm_bridge_chain_enable);
@@ -370,15 +401,22 @@ EXPORT_SYMBOL(drm_bridge_chain_enable);
void drm_atomic_bridge_chain_disable(struct drm_bridge *bridge,
struct drm_atomic_state *state)
{
+ struct drm_encoder *encoder;
+ struct drm_bridge *iter;
+
if (!bridge)
return;
- drm_atomic_bridge_chain_disable(bridge->next, state);
+ encoder = bridge->encoder;
+ list_for_each_entry_reverse(iter, &encoder->bridge_chain, chain_node) {
+ if (iter->funcs->atomic_disable)
+ iter->funcs->atomic_disable(iter, state);
+ else if (iter->funcs->disable)
+ iter->funcs->disable(iter);
- if (bridge->funcs->atomic_disable)
- bridge->funcs->atomic_disable(bridge, state);
- else if (bridge->funcs->disable)
- bridge->funcs->disable(bridge);
+ if (iter == bridge)
+ break;
+ }
}
EXPORT_SYMBOL(drm_atomic_bridge_chain_disable);
@@ -398,15 +436,18 @@ EXPORT_SYMBOL(drm_atomic_bridge_chain_disable);
void drm_atomic_bridge_chain_post_disable(struct drm_bridge *bridge,
struct drm_atomic_state *state)
{
+ struct drm_encoder *encoder;
+
if (!bridge)
return;
- if (bridge->funcs->atomic_post_disable)
- bridge->funcs->atomic_post_disable(bridge, state);
- else if (bridge->funcs->post_disable)
- bridge->funcs->post_disable(bridge);
-
- drm_atomic_bridge_chain_post_disable(bridge->next, state);
+ encoder = bridge->encoder;
+ list_for_each_entry_from(bridge, &encoder->bridge_chain, chain_node) {
+ if (bridge->funcs->atomic_post_disable)
+ bridge->funcs->atomic_post_disable(bridge, state);
+ else if (bridge->funcs->post_disable)
+ bridge->funcs->post_disable(bridge);
+ }
}
EXPORT_SYMBOL(drm_atomic_bridge_chain_post_disable);
@@ -426,15 +467,22 @@ EXPORT_SYMBOL(drm_atomic_bridge_chain_post_disable);
void drm_atomic_bridge_chain_pre_enable(struct drm_bridge *bridge,
struct drm_atomic_state *state)
{
+ struct drm_encoder *encoder;
+ struct drm_bridge *iter;
+
if (!bridge)
return;
- drm_atomic_bridge_chain_pre_enable(bridge->next, state);
+ encoder = bridge->encoder;
+ list_for_each_entry_reverse(iter, &encoder->bridge_chain, chain_node) {
+ if (iter->funcs->atomic_pre_enable)
+ iter->funcs->atomic_pre_enable(iter, state);
+ else if (iter->funcs->pre_enable)
+ iter->funcs->pre_enable(iter);
- if (bridge->funcs->atomic_pre_enable)
- bridge->funcs->atomic_pre_enable(bridge, state);
- else if (bridge->funcs->pre_enable)
- bridge->funcs->pre_enable(bridge);
+ if (iter == bridge)
+ break;
+ }
}
EXPORT_SYMBOL(drm_atomic_bridge_chain_pre_enable);
@@ -453,15 +501,18 @@ EXPORT_SYMBOL(drm_atomic_bridge_chain_pre_enable);
void drm_atomic_bridge_chain_enable(struct drm_bridge *bridge,
struct drm_atomic_state *state)
{
+ struct drm_encoder *encoder;
+
if (!bridge)
return;
- if (bridge->funcs->atomic_enable)
- bridge->funcs->atomic_enable(bridge, state);
- else if (bridge->funcs->enable)
- bridge->funcs->enable(bridge);
-
- drm_atomic_bridge_chain_enable(bridge->next, state);
+ encoder = bridge->encoder;
+ list_for_each_entry_from(bridge, &encoder->bridge_chain, chain_node) {
+ if (bridge->funcs->atomic_enable)
+ bridge->funcs->atomic_enable(bridge, state);
+ else if (bridge->funcs->enable)
+ bridge->funcs->enable(bridge);
+ }
}
EXPORT_SYMBOL(drm_atomic_bridge_chain_enable);
diff --git a/drivers/gpu/drm/drm_encoder.c b/drivers/gpu/drm/drm_encoder.c
index a2cc7e7241a9..e555281f43d4 100644
--- a/drivers/gpu/drm/drm_encoder.c
+++ b/drivers/gpu/drm/drm_encoder.c
@@ -140,6 +140,7 @@ int drm_encoder_init(struct drm_device *dev,
goto out_put;
}
+ INIT_LIST_HEAD(&encoder->bridge_chain);
list_add_tail(&encoder->head, &dev->mode_config.encoder_list);
encoder->index = dev->mode_config.num_encoder++;
@@ -160,23 +161,16 @@ EXPORT_SYMBOL(drm_encoder_init);
void drm_encoder_cleanup(struct drm_encoder *encoder)
{
struct drm_device *dev = encoder->dev;
+ struct drm_bridge *bridge, *next;
/* Note that the encoder_list is considered to be static; should we
* remove the drm_encoder at runtime we would have to decrement all
* the indices on the drm_encoder after us in the encoder_list.
*/
- if (encoder->bridge) {
- struct drm_bridge *bridge;
- struct drm_bridge *next;
-
- bridge = drm_bridge_chain_get_first_bridge(encoder);
- while (bridge) {
- next = drm_bridge_get_next_bridge(bridge);
- drm_bridge_detach(bridge);
- bridge = next;
- }
- }
+ list_for_each_entry_safe(bridge, next, &encoder->bridge_chain,
+ chain_node)
+ drm_bridge_detach(bridge);
drm_mode_object_unregister(dev, &encoder->base);
kfree(encoder->name);
diff --git a/drivers/gpu/drm/exynos/exynos_drm_dsi.c b/drivers/gpu/drm/exynos/exynos_drm_dsi.c
index d984097704b8..7de82e22252a 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_dsi.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_dsi.c
@@ -255,6 +255,7 @@ struct exynos_dsi {
struct mipi_dsi_host dsi_host;
struct drm_connector connector;
struct drm_panel *panel;
+ struct list_head bridge_chain;
struct drm_bridge *out_bridge;
struct device *dev;
@@ -1522,7 +1523,7 @@ static int exynos_dsi_host_attach(struct mipi_dsi_host *host,
if (out_bridge) {
drm_bridge_attach(encoder, out_bridge, NULL);
dsi->out_bridge = out_bridge;
- encoder->bridge = NULL;
+ list_splice(&encoder->bridge_chain, &dsi->bridge_chain);
} else {
int ret = exynos_dsi_create_connector(encoder);
@@ -1588,6 +1589,7 @@ static int exynos_dsi_host_detach(struct mipi_dsi_host *host,
if (dsi->out_bridge->funcs->detach)
dsi->out_bridge->funcs->detach(dsi->out_bridge);
dsi->out_bridge = NULL;
+ INIT_LIST_HEAD(&dsi->bridge_chain);
}
if (drm->mode_config.poll_enabled)
@@ -1735,6 +1737,7 @@ static int exynos_dsi_probe(struct platform_device *pdev)
init_completion(&dsi->completed);
spin_lock_init(&dsi->transfer_lock);
INIT_LIST_HEAD(&dsi->transfer_list);
+ INIT_LIST_HEAD(&dsi->bridge_chain);
dsi->dsi_host.ops = &exynos_dsi_ops;
dsi->dsi_host.dev = dev;
diff --git a/drivers/gpu/drm/vc4/vc4_dsi.c b/drivers/gpu/drm/vc4/vc4_dsi.c
index ff81b54ea281..6c5b80ad6154 100644
--- a/drivers/gpu/drm/vc4/vc4_dsi.c
+++ b/drivers/gpu/drm/vc4/vc4_dsi.c
@@ -499,6 +499,7 @@ struct vc4_dsi {
struct mipi_dsi_host dsi_host;
struct drm_encoder *encoder;
struct drm_bridge *bridge;
+ struct list_head bridge_chain;
void __iomem *regs;
@@ -1460,6 +1461,8 @@ static int vc4_dsi_bind(struct device *dev, struct device *master, void *data)
GFP_KERNEL);
if (!vc4_dsi_encoder)
return -ENOMEM;
+
+ INIT_LIST_HEAD(&dsi->bridge_chain);
vc4_dsi_encoder->base.type = VC4_ENCODER_TYPE_DSI1;
vc4_dsi_encoder->dsi = dsi;
dsi->encoder = &vc4_dsi_encoder->base.base;
@@ -1610,7 +1613,7 @@ static int vc4_dsi_bind(struct device *dev, struct device *master, void *data)
* from our driver, since we need to sequence them within the
* encoder's enable/disable paths.
*/
- dsi->encoder->bridge = NULL;
+ list_splice(&dsi->encoder->bridge_chain, &dsi->bridge_chain);
if (dsi->port == 0)
vc4_debugfs_add_regset32(drm, "dsi0_regs", &dsi->regset);
@@ -1632,6 +1635,11 @@ static void vc4_dsi_unbind(struct device *dev, struct device *master,
if (dsi->bridge)
pm_runtime_disable(dev);
+ /*
+ * Restore the bridge_chain so the bridge detach procedure can happen
+ * normally.
+ */
+ list_splice(&dsi->bridge_chain, &dsi->encoder->bridge_chain);
vc4_dsi_encoder_destroy(dsi->encoder);
if (dsi->port == 1)
diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h
index bd78c256b1ed..c118726469ee 100644
--- a/include/drm/drm_bridge.h
+++ b/include/drm/drm_bridge.h
@@ -384,8 +384,8 @@ struct drm_bridge {
struct drm_device *dev;
/** @encoder: encoder to which this bridge is connected */
struct drm_encoder *encoder;
- /** @next: the next bridge in the encoder chain */
- struct drm_bridge *next;
+ /** @chain_node: used to form a bridge chain */
+ struct list_head chain_node;
#ifdef CONFIG_OF
/** @of_node: device node pointer to the bridge */
struct device_node *of_node;
@@ -420,7 +420,10 @@ int drm_bridge_attach(struct drm_encoder *encoder, struct drm_bridge *bridge,
static inline struct drm_bridge *
drm_bridge_get_next_bridge(struct drm_bridge *bridge)
{
- return bridge->next;
+ if (list_is_last(&bridge->chain_node, &bridge->encoder->bridge_chain))
+ return NULL;
+
+ return list_next_entry(bridge, chain_node);
}
/**
@@ -434,7 +437,8 @@ drm_bridge_get_next_bridge(struct drm_bridge *bridge)
static inline struct drm_bridge *
drm_bridge_chain_get_first_bridge(struct drm_encoder *encoder)
{
- return encoder->bridge;
+ return list_first_entry_or_null(&encoder->bridge_chain,
+ struct drm_bridge, chain_node);
}
bool drm_bridge_chain_mode_fixup(struct drm_bridge *bridge,
diff --git a/include/drm/drm_encoder.h b/include/drm/drm_encoder.h
index f06164f44efe..5623994b6e9e 100644
--- a/include/drm/drm_encoder.h
+++ b/include/drm/drm_encoder.h
@@ -172,7 +172,12 @@ struct drm_encoder {
* &drm_connector_state.crtc.
*/
struct drm_crtc *crtc;
- struct drm_bridge *bridge;
+
+ /**
+ * @bridge_chain: Bridges attached to this encoder.
+ */
+ struct list_head bridge_chain;
+
const struct drm_encoder_funcs *funcs;
const struct drm_encoder_helper_funcs *helper_private;
};
--
2.23.0
