drm/bridge: Add a function to abstract away panels

[ Upstream commit 87ea95808d53e56b03e620e8f8f3add48899a88d ]

Display drivers so far need to have a lot of boilerplate to first
retrieve either the

drm/bridge: Add a function to abstract away panels

[ Upstream commit 87ea95808d53e56b03e620e8f8f3add48899a88d ]

Display drivers so far need to have a lot of boilerplate to first
retrieve either the panel or bridge that they are connected to using
drm_of_find_panel_or_bridge(), and then either deal with each with ad-hoc
functions or create a drm panel bridge through drm_panel_bridge_add.

In order to reduce the boilerplate and hopefully create a path of least
resistance towards using the DRM panel bridge layer, let's create the
function devm_drm_of_get_bridge() to reduce that boilerplate.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210910130941.1740182-2-maxime@cerno.tech
Signed-off-by: Sasha Levin <sashal@kernel.org>

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drm: bridge: Mark deprecated operations in drm_bridge_funcs

drm_bridge_funcs includes several duplicated operations as atomic
variants have been added over time.
New bridge drivers shall use the ato

drm: bridge: Mark deprecated operations in drm_bridge_funcs

drm_bridge_funcs includes several duplicated operations as atomic
variants have been added over time.
New bridge drivers shall use the atomic variants - mark the deprecated
operations to try to avoid usage in new bridge drivers.

v2:
- Drop out-dated comment about state in mode_set (Laurent)
- Added missing "the" in a description

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Acked-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210710084240.281063-1-sam@ravnborg.org

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drm: drm_bridge.h: delete duplicated word in comment

Drop doubled word "should" in a comment.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vett

drm: drm_bridge.h: delete duplicated word in comment

Drop doubled word "should" in a comment.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200715052349.23319-2-rdunlap@infradead.org

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drm: bridge: Pass drm_display_info to drm_bridge_funcs .mode_valid()

When validating a mode, bridges may need to do so in the context of a
display, as specified by drm_display_info. An example is th

drm: bridge: Pass drm_display_info to drm_bridge_funcs .mode_valid()

When validating a mode, bridges may need to do so in the context of a
display, as specified by drm_display_info. An example is the meson
dw-hdmi bridge that needs to consider the YUV 4:2:0 output format to
perform clock calculations.

Bridges that need the display info currently retrieve it from the
drm_connector created by the bridge. This gets in the way of moving
connector creation out of bridge drivers. To make this possible, pass
the drm_display_info to drm_bridge_funcs .mode_valid().

Changes to the bridge drivers have been performed with the following
coccinelle semantic patch and have been compile-tested.

@ rule1 @
identifier funcs;
identifier fn;
@@
struct drm_bridge_funcs funcs = {
...,
.mode_valid = fn
};

@ depends on rule1 @
identifier rule1.fn;
identifier bridge;
identifier mode;
@@
enum drm_mode_status fn(
struct drm_bridge *bridge,
+ const struct drm_display_info *info,
const struct drm_display_mode *mode
)
{
...
}

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Guido Günther <agx@sigxcpu.org> # for the nwl-dsi part:
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200526011505.31884-11-laurent.pinchart+renesas@ideasonboard.com

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drm/bridge: Extend bridge API to disable connector creation

Most bridge drivers create a DRM connector to model the connector at the
output of the bridge. This model is historical and has worked pre

drm/bridge: Extend bridge API to disable connector creation

Most bridge drivers create a DRM connector to model the connector at the
output of the bridge. This model is historical and has worked pretty
well so far, but causes several issues:

- It prevents supporting more complex display pipelines where DRM
connector operations are split over multiple components. For instance a
pipeline with a bridge connected to the DDC signals to read EDID data,
and another one connected to the HPD signal to detect connection and
disconnection, will not be possible to support through this model.

- It requires every bridge driver to implement similar connector
handling code, resulting in code duplication.

- It assumes that a bridge will either be wired to a connector or to
another bridge, but doesn't support bridges that can be used in both
positions very well (although there is some ad-hoc support for this in
the analogix_dp bridge driver).

In order to solve these issues, ownership of the connector should be
moved to the display controller driver (where it can be implemented
using helpers provided by the core).

Extend the bridge API to allow disabling connector creation in bridge
drivers as a first step towards the new model. The new flags argument to
the bridge .attach() operation allows instructing the bridge driver to
skip creating a connector. Unconditionally set the new flags argument to
0 for now to keep the existing behaviour, and modify all existing bridge
drivers to return an error when connector creation is not requested as
they don't support this feature yet.

The change is based on the following semantic patch, with manual review
and edits.

@ rule1 @
identifier funcs;
identifier fn;
@@
struct drm_bridge_funcs funcs = {
...,
.attach = fn
};

@ depends on rule1 @
identifier rule1.fn;
identifier bridge;
statement S, S1;
@@
int fn(
struct drm_bridge *bridge
+ , enum drm_bridge_attach_flags flags
)
{
... when != S
+ if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR) {
+ DRM_ERROR("Fix bridge driver to make connector optional!");
+ return -EINVAL;
+ }
+
S1
...
}

@ depends on rule1 @
identifier rule1.fn;
identifier bridge, flags;
expression E1, E2, E3;
@@
int fn(
struct drm_bridge *bridge,
enum drm_bridge_attach_flags flags
) {
<...
drm_bridge_attach(E1, E2, E3
+ , flags
)
...>
}

@@
expression E1, E2, E3;
@@
drm_bridge_attach(E1, E2, E3
+ , 0
)

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Tested-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200226112514.12455-10-laurent.pinchart@ideasonboard.com

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drm/bridge: Add interlace_allowed flag to drm_bridge

In preparation for a connector creation helper based on a chain of
bridges, add a flag to the drm_bridge structure to report support for
interlac

drm/bridge: Add interlace_allowed flag to drm_bridge

In preparation for a connector creation helper based on a chain of
bridges, add a flag to the drm_bridge structure to report support for
interlaced modes. This will be used to set the connector's
interlace_allowed flag.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200226112514.12455-9-laurent.pinchart@ideasonboard.com

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drm/bridge: Add connector-related bridge operations and data

To support implementation of DRM connectors on top of DRM bridges
instead of by bridges, the drm_bridge needs to expose new operations an

drm/bridge: Add connector-related bridge operations and data

To support implementation of DRM connectors on top of DRM bridges
instead of by bridges, the drm_bridge needs to expose new operations and
data:

- Output detection, hot-plug notification, mode retrieval and EDID
retrieval operations
- Bitmask of supported operations
- Bridge output type
- I2C adapter for DDC access

Add and document these.

Three new bridge helper functions are also added to handle hot plug
notification in a way that is as transparent as possible for the
bridges.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Tested-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200226112514.12455-8-laurent.pinchart@ideasonboard.com

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drm/bridge: Fix atomic state ops documentation

The drm_bridge_funcs atomic_state_duplicate and atomic_state_destroy
operations are erroneously documented as having a default implementation
if not im

drm/bridge: Fix atomic state ops documentation

The drm_bridge_funcs atomic_state_duplicate and atomic_state_destroy
operations are erroneously documented as having a default implementation
if not implemented in bridge drivers. This isn't correct, fix the
documentation.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200226112514.12455-6-laurent.pinchart@ideasonboard.com

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drm/bridge: Fix the bridge kernel doc

Commit 751465913f04 ("drm/bridge: Add a drm_bridge_state object")
introduced new helpers and hooks but the kernel was slightly broken.
Fix that now.

v2:
* Fix

drm/bridge: Fix the bridge kernel doc

Commit 751465913f04 ("drm/bridge: Add a drm_bridge_state object")
introduced new helpers and hooks but the kernel was slightly broken.
Fix that now.

v2:
* Fix the drm_atomic_add_encoder_bridges() doc

Fixes: 751465913f04 ("drm/bridge: Add a drm_bridge_state object")
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200218151503.595825-1-boris.brezillon@collabora.com

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drm/bridge: Add the necessary bits to support bus format negotiation

drm_bridge_state is extended to describe the input and output bus
configurations. These bus configurations are exposed through th

drm/bridge: Add the necessary bits to support bus format negotiation

drm_bridge_state is extended to describe the input and output bus
configurations. These bus configurations are exposed through the
drm_bus_cfg struct which encodes the configuration of a physical
bus between two components in an output pipeline, usually between
two bridges, an encoder and a bridge, or a bridge and a connector.

The bus configuration is stored in drm_bridge_state separately for
the input and output buses, as seen from the point of view of each
bridge. The bus configuration of a bridge output is usually identical
to the configuration of the next bridge's input, but may differ if
the signals are modified between the two bridges, for instance by an
inverter on the board. The input and output configurations of a
bridge may differ if the bridge modifies the signals internally,
for instance by performing format conversion, or*modifying signals
polarities.

Bus format negotiation is automated by the core, drivers just have
to implement the ->atomic_get_{output,input}_bus_fmts() hooks if they
want to take part to this negotiation. Negotiation happens in reverse
order, starting from the last element of the chain (the one directly
connected to the display) up to the first element of the chain (the one
connected to the encoder).
During this negotiation all supported formats are tested until we find
one that works, meaning that the formats array should be in decreasing
preference order (assuming the driver has a preference order).

Note that the bus format negotiation works even if some elements in the
chain don't implement the ->atomic_get_{output,input}_bus_fmts() hooks.
In that case, the core advertises only MEDIA_BUS_FMT_FIXED and lets
the previous bridge element decide what to do (most of the time, bridge
drivers will pick a default bus format or extract this piece of
information from somewhere else, like a FW property).

v10:
* Add changelog to the commit message

v9:
* No changes

v8:
* Fix a test in drm_atomic_bridge_chain_select_bus_fmts() (Reported by
Jonas)

v7:
* Adapt the code to deal with the fact that not all bridges in the
chain have a bridge state

v5 -> v6:
* No changes

v4:
* Enhance the doc
* Fix typos
* Rename some parameters/fields
* Reword the commit message

v3:
* Fix the commit message (Reported by Laurent)
* Document the fact that bus formats should not be directly modified by
drivers (Suggested by Laurent)
* Document the fact that format order matters (Suggested by Laurent)
* Propagate bus flags by default
* Document the fact that drivers can tweak bus flags if needed
* Let ->atomic_get_{output,input}_bus_fmts() allocate the bus format
array (Suggested by Laurent)
* Add a drm_atomic_helper_bridge_propagate_bus_fmt()
* Mandate that bridge drivers return accurate input_fmts even if they
are known to be the first element in the bridge chain

v2:
* Rework things to support more complex use cases

Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
[narmstrong: fixed doc in include/drm/drm_bridge.h:69 fmt->format]
Reviewed-by: Jernej Skrabec <jernej.skrabec@siol.net>
Tested-by: Jonas Karlman <jonas@kwiboo.se>
Link: https://patchwork.freedesktop.org/patch/msgid/20200128135514.108171-7-boris.brezillon@collabora.com

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drm/bridge: Add an ->atomic_check() hook

So that bridge drivers have a way to check/reject an atomic operation.
The drm_atomic_bridge_chain_check() (which is just a wrapper around
the ->atomic_check

drm/bridge: Add an ->atomic_check() hook

So that bridge drivers have a way to check/reject an atomic operation.
The drm_atomic_bridge_chain_check() (which is just a wrapper around
the ->atomic_check() hook) is called in place of
drm_bridge_chain_mode_fixup() (when ->atomic_check() is not implemented,
the core falls back on ->mode_fixup(), so the behavior should stay
the same for existing bridge drivers).

v10:
* Add changelog to the commit message

v8 -> v9:
* No changes

v7:
* Fix a NULL pointer dereference

v5 -> v6:
* No changes

v4:
* Add R-bs

v3:
* No changes

v2:
* Clarify the fact that ->atomic_check() is replacing ->mode_fixup()

Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed by: Jernej Skrabec <jernej.skrabec@siol.net>
Tested-by: Jonas Karlman <jonas@kwiboo.se>
Link: https://patchwork.freedesktop.org/patch/msgid/20200128135514.108171-6-boris.brezillon@collabora.com

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drm/bridge: Patch atomic hooks to take a drm_bridge_state

This way the drm_bridge_funcs interface is consistent with the rest of
the subsystem.

The drivers implementing those hooks are patched too.

drm/bridge: Patch atomic hooks to take a drm_bridge_state

This way the drm_bridge_funcs interface is consistent with the rest of
the subsystem.

The drivers implementing those hooks are patched too.

v10:
* Add changelog to the commit message

v8 -> v9:
* No changes

v7:
* Adjust things to the bridge_state changes

v6:
* Also fixed rcar-du/rcar_lvds.c same as analogix/analogix_dp_core.c

v5:
* No changes

v4:
* Rename func params into old_bridge_state
* Add Laurent's Rb

v3:
* Old state clarification moved to a separate patch

v2:
* Pass the old bridge state

Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
[narmstrong: renamed state as old_bridge_state in rcar_lvds_atomic_disable]
Reviewed by: Jernej Skrabec <jernej.skrabec@siol.net>
Tested-by: Jonas Karlman <jonas@kwiboo.se>
Link: https://patchwork.freedesktop.org/patch/msgid/20200128135514.108171-5-boris.brezillon@collabora.com

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drm/bridge: Add a drm_bridge_state object

One of the last remaining objects to not have its atomic state.

This is being motivated by our attempt to support runtime bus-format
negotiation between el

drm/bridge: Add a drm_bridge_state object

One of the last remaining objects to not have its atomic state.

This is being motivated by our attempt to support runtime bus-format
negotiation between elements of the bridge chain.
This patch just paves the road for such a feature by adding a new
drm_bridge_state object inheriting from drm_private_obj so we can
re-use some of the existing state initialization/tracking logic.

v10:
* Add changelog to the commit message

v9:
* Clarify the fact that the bridge->atomic_reset() and
{connector,plane,crtc,...}->reset() semantics are different
* Move the drm_atomic_private_obj_init() call back to
drm_bridge_attach()
* Check the presence of ->atomic_duplicate_state instead of
->atomic_reset in drm_atomic_add_encoder_bridges()
* Fix copy&paste errors in the atomic bridge state helpers doc
* Add A-b/R-b tags

v8:
* Move bridge state helpers out of the CONFIG_DEBUGFS section

v7:
* Move helpers, struct-defs, ... to atomic helper files to avoid the
drm -> drm_kms_helper -> drm circular dep
* Stop providing default implementation for atomic state reset,
duplicate and destroy hooks (has to do with the helper/core split)
* Drop all R-b/T-b as helpers have now be moved to other places

v6:
* Made helpers private, removed doc and moved them to satisfy dependencies
* Renamed helpers to _default_

v5:
* Re-introduced the helpers from v4

v4:
* Fix the doc
* Kill default helpers (inlined)
* Fix drm_atomic_get_bridge_state() to check for an ERR_PTR()
* Add Neil's R-b

v3:
* No changes

v2:
* Use drm_for_each_bridge_in_chain()
* Rename helpers to be more consistent with the rest of the DRM API
* Improve/fix the doc

Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200128135514.108171-2-boris.brezillon@collabora.com

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Revert "drm/bridge: Add a drm_bridge_state object"

This reverts commit 6ed7e9625fa6 ("drm/bridge: Add a drm_bridge_state
object") which introduced a circular dependency between drm.ko and
drm_kms_he

Revert "drm/bridge: Add a drm_bridge_state object"

This reverts commit 6ed7e9625fa6 ("drm/bridge: Add a drm_bridge_state
object") which introduced a circular dependency between drm.ko and
drm_kms_helper.ko. Looks like the helper/core split is not appropriate
and fixing that is not simple.

Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200107185807.606999-6-boris.brezillon@collabora.com

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Revert "drm/bridge: Patch atomic hooks to take a drm_bridge_state"

This reverts commit f7619a58ef92 ("drm/bridge: Patch atomic hooks to
take a drm_bridge_state"). Commit 6ed7e9625fa6 ("drm/bridge: A

Revert "drm/bridge: Patch atomic hooks to take a drm_bridge_state"

This reverts commit f7619a58ef92 ("drm/bridge: Patch atomic hooks to
take a drm_bridge_state"). Commit 6ed7e9625fa6 ("drm/bridge: Add a
drm_bridge_state object") introduced a circular dependency between
drm.ko and drm_kms_helper.ko which uncovered a misdesign in how the
whole thing was implemented. Let's revert all patches depending on the
bridge_state infrastructure for now.

Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200107185807.606999-5-boris.brezillon@collabora.com

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Revert "drm/bridge: Add an ->atomic_check() hook"

This reverts commit b86d895524ab ("drm/bridge: Add an ->atomic_check()
hook"). Commit 6ed7e9625fa6 ("drm/bridge: Add a drm_bridge_state
object") int

Revert "drm/bridge: Add an ->atomic_check() hook"

This reverts commit b86d895524ab ("drm/bridge: Add an ->atomic_check()
hook"). Commit 6ed7e9625fa6 ("drm/bridge: Add a drm_bridge_state
object") introduced a circular dependency between drm.ko and
drm_kms_helper.ko which uncovered a misdesign in how the whole thing
was implemented. Let's revert all patches depending on the bridge_state
infrastructure for now.

Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200107185807.606999-4-boris.brezillon@collabora.com

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Revert "drm/bridge: Add the necessary bits to support bus format negotiation"

This reverts commit e351e4d5eaec ("drm/bridge: Add the necessary bits
to support bus format negotiation"). Commit 6ed7e9

Revert "drm/bridge: Add the necessary bits to support bus format negotiation"

This reverts commit e351e4d5eaec ("drm/bridge: Add the necessary bits
to support bus format negotiation"). Commit 6ed7e9625fa6 ("drm/bridge:
Add a drm_bridge_state object") introduced a circular dependency
between drm.ko and drm_kms_helper.ko which uncovered a misdesign in
how the whole thing was implemented. Let's revert all patches depending
on the bridge_state infrastructure for now.

Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200107185807.606999-3-boris.brezillon@collabora.com

show more ...

drm/bridge: Add the necessary bits to support bus format negotiation

drm_bridge_state is extended to describe the input and output bus
configurations. These bus configurations are exposed through th

drm/bridge: Add the necessary bits to support bus format negotiation

drm_bridge_state is extended to describe the input and output bus
configurations. These bus configurations are exposed through the
drm_bus_cfg struct which encodes the configuration of a physical
bus between two components in an output pipeline, usually between
two bridges, an encoder and a bridge, or a bridge and a connector.

The bus configuration is stored in drm_bridge_state separately for
the input and output buses, as seen from the point of view of each
bridge. The bus configuration of a bridge output is usually identical
to the configuration of the next bridge's input, but may differ if
the signals are modified between the two bridges, for instance by an
inverter on the board. The input and output configurations of a
bridge may differ if the bridge modifies the signals internally,
for instance by performing format conversion, or*modifying signals
polarities.

Bus format negotiation is automated by the core, drivers just have
to implement the ->atomic_get_{output,input}_bus_fmts() hooks if they
want to take part to this negotiation. Negotiation happens in reverse
order, starting from the last element of the chain (the one directly
connected to the display) up to the first element of the chain (the one
connected to the encoder).
During this negotiation all supported formats are tested until we find
one that works, meaning that the formats array should be in decreasing
preference order (assuming the driver has a preference order).

Note that the bus format negotiation works even if some elements in the
chain don't implement the ->atomic_get_{output,input}_bus_fmts() hooks.
In that case, the core advertises only MEDIA_BUS_FMT_FIXED and lets
the previous bridge element decide what to do (most of the time, bridge
drivers will pick a default bus format or extract this piece of
information from somewhere else, like a FW property).

Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed by: Jernej Skrabec <jernej.skrabec@siol.net>
Tested-by: Jonas Karlman <jonas@kwiboo.se>
[narmstrong: fixed doc in include/drm/drm_bridge.h:69 fmt->format]
Link: https://patchwork.freedesktop.org/patch/msgid/20200106143409.32321-5-narmstrong@baylibre.com

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drm/bridge: Add an ->atomic_check() hook

So that bridge drivers have a way to check/reject an atomic operation.
The drm_atomic_bridge_chain_check() (which is just a wrapper around
the ->atomic_check

drm/bridge: Add an ->atomic_check() hook

So that bridge drivers have a way to check/reject an atomic operation.
The drm_atomic_bridge_chain_check() (which is just a wrapper around
the ->atomic_check() hook) is called in place of
drm_bridge_chain_mode_fixup() (when ->atomic_check() is not implemented,
the core falls back on ->mode_fixup(), so the behavior should stay
the same for existing bridge drivers).

Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed by: Jernej Skrabec <jernej.skrabec@siol.net>
Tested-by: Jonas Karlman <jonas@kwiboo.se>
Link: https://patchwork.freedesktop.org/patch/msgid/20200106143409.32321-4-narmstrong@baylibre.com

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drm/bridge: Patch atomic hooks to take a drm_bridge_state

This way the drm_bridge_funcs interface is consistent with the rest of
the subsystem.

The only driver implementing those hooks (analogix DP

drm/bridge: Patch atomic hooks to take a drm_bridge_state

This way the drm_bridge_funcs interface is consistent with the rest of
the subsystem.

The only driver implementing those hooks (analogix DP) is patched too.

Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed by: Jernej Skrabec <jernej.skrabec@siol.net>
Tested-by: Jonas Karlman <jonas@kwiboo.se>
[narmstrong: renamed state as old_bridge_state in rcar_lvds_atomic_disable]
Link: https://patchwork.freedesktop.org/patch/msgid/20200106143409.32321-3-narmstrong@baylibre.com

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drm/bridge: Add a drm_bridge_state object

One of the last remaining objects to not have its atomic state.

This is being motivated by our attempt to support runtime bus-format
negotiation between el

drm/bridge: Add a drm_bridge_state object

One of the last remaining objects to not have its atomic state.

This is being motivated by our attempt to support runtime bus-format
negotiation between elements of the bridge chain.
This patch just paves the road for such a feature by adding a new
drm_bridge_state object inheriting from drm_private_obj so we can
re-use some of the existing state initialization/tracking logic.

Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed by: Jernej Skrabec <jernej.skrabec@siol.net>
Tested-by: Jonas Karlman <jonas@kwiboo.se>
Link: https://patchwork.freedesktop.org/patch/msgid/20200106143409.32321-2-narmstrong@baylibre.com

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drm: get drm_bridge_panel connector via helper

The drm_connector created by drm_panel_bridge was accessed
via drm_panel.connector.
Avoid the detour around drm_panel by providing a simple get method.

drm: get drm_bridge_panel connector via helper

The drm_connector created by drm_panel_bridge was accessed
via drm_panel.connector.
Avoid the detour around drm_panel by providing a simple get method.
This avoids direct access to the connector field in drm_panel in
the two users.

The change is done in preparation for removal of drm_panel.connector.

Update pl111 and tve200 to use the new helper.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
Cc: Jonas Karlman <jonas@kwiboo.se>
Cc: Jernej Skrabec <jernej.skrabec@siol.net>
Cc: Eric Anholt <eric@anholt.net>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20191207140353.23967-5-sam@ravnborg.org

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drm/bridge: Clarify the atomic enable/disable hooks semantics

The [pre_]enable/[post_]disable hooks are passed the old atomic state.
Update the doc and rename the arguments to make it clear.

Signed

drm/bridge: Clarify the atomic enable/disable hooks semantics

The [pre_]enable/[post_]disable hooks are passed the old atomic state.
Update the doc and rename the arguments to make it clear.

Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191203141515.3597631-8-boris.brezillon@collabora.com

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drm/bridge: Add the drm_bridge_get_prev_bridge() helper

The drm_bridge_get_prev_bridge() helper will be useful for bridge
drivers that want to do bus format negotiation with their neighbours.

Signe

drm/bridge: Add the drm_bridge_get_prev_bridge() helper

The drm_bridge_get_prev_bridge() helper will be useful for bridge
drivers that want to do bus format negotiation with their neighbours.

Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191203141515.3597631-7-boris.brezillon@collabora.com

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drm/bridge: Add the drm_for_each_bridge_in_chain() helper

To iterate over all bridges attached to a specific encoder.

Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-b

drm/bridge: Add the drm_for_each_bridge_in_chain() helper

To iterate over all bridges attached to a specific encoder.

Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191203141515.3597631-6-boris.brezillon@collabora.com

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