[PATCH v3 07/21] drm/bridge: Make the bridge chain a double-linked list
Boris Brezillon
boris.brezillon at collabora.com
Wed Oct 23 15:44:58 UTC 2019
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 at collabora.com>
---
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 +---
include/drm/drm_bridge.h | 12 ++-
include/drm/drm_encoder.h | 9 +-
4 files changed, 135 insertions(+), 73 deletions(-)
diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c
index 54c874493c57..c5cf8a9c4237 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.
*/
@@ -114,6 +114,7 @@ EXPORT_SYMBOL(drm_bridge_remove);
int drm_bridge_attach(struct drm_encoder *encoder, struct drm_bridge *bridge,
struct drm_bridge *previous)
{
+ LIST_HEAD(tmp_list);
int ret;
if (!encoder || !bridge)
@@ -127,6 +128,7 @@ int drm_bridge_attach(struct drm_encoder *encoder, struct drm_bridge *bridge,
bridge->dev = encoder->dev;
bridge->encoder = encoder;
+ list_add_tail(&bridge->chain_node, &tmp_list);
if (bridge->funcs->attach) {
ret = bridge->funcs->attach(bridge);
@@ -138,9 +140,9 @@ int drm_bridge_attach(struct drm_encoder *encoder, struct drm_bridge *bridge,
}
if (previous)
- previous->next = bridge;
+ list_splice(&tmp_list, &previous->chain_node);
else
- encoder->bridge = bridge;
+ list_splice(&tmp_list, &encoder->bridge_chain);
return 0;
}
@@ -157,6 +159,7 @@ 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 +193,22 @@ 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 +231,24 @@ 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;
+
+ 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 (bridge->funcs->mode_valid)
ret = bridge->funcs->mode_valid(bridge, mode);
+ if (ret != MODE_OK)
+ return ret;
+ }
- 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 +264,20 @@ 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 +294,16 @@ 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 +323,16 @@ 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 +349,17 @@ 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 +375,16 @@ 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 +403,23 @@ 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 +439,19 @@ 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 +471,23 @@ 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, &bridge->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 +506,19 @@ 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, &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 4fe9e723e227..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 = bridge->next;
- 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/include/drm/drm_bridge.h b/include/drm/drm_bridge.h
index 27eef63ce0ff..3ab16c95e59e 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_chain_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_chain_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..9b3dde177c81 100644
--- a/include/drm/drm_encoder.h
+++ b/include/drm/drm_encoder.h
@@ -172,7 +172,14 @@ struct drm_encoder {
* &drm_connector_state.crtc.
*/
struct drm_crtc *crtc;
- struct drm_bridge *bridge;
+
+ /**
+ * @bridge_chain: Bridges attached to this encoder. The first entry of
+ * this list is always &drm_encoder.bridge. It may be followed by other
+ * bridge entities.
+ */
+ struct list_head bridge_chain;
+
const struct drm_encoder_funcs *funcs;
const struct drm_encoder_helper_funcs *helper_private;
};
--
2.21.0
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