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
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
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
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
This reverts commit 6ed7e9625f ("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
This reverts commit f7619a58ef ("drm/bridge: Patch atomic hooks to
take a drm_bridge_state"). Commit 6ed7e9625f ("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
This reverts commit b86d895524 ("drm/bridge: Add an ->atomic_check()
hook"). Commit 6ed7e9625f ("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
This reverts commit e351e4d5ea ("drm/bridge: Add the necessary bits
to support bus format negotiation"). Commit 6ed7e9625f ("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
This reverts commit b18398c16e ("drm/bridge: Fix a NULL pointer
dereference in drm_atomic_bridge_chain_check()"). Commit 6ed7e9625f
("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/20200107185807.606999-2-boris.brezillon@collabora.com
drm_atomic_bridge_chain_check() callers can pass a NULL bridge. Let's
bail out before dereferencing the bridge pointer when that happens.
Reported-by: Chris Wilson <chris@chris-wilson.co.uk>
Fixes: b86d895524 ("drm/bridge: Add an ->atomic_check() hook")
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200107113031.435604-1-boris.brezillon@collabora.com
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
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
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
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
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
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@collabora.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191203141515.3597631-5-boris.brezillon@collabora.com
Change the prefix of bridge helpers targeting a bridge chain from
drm_bridge_ to drm_bridge_chain_ to better reflect the fact that
the operation will happen on all elements of chain, starting at the
bridge passed in argument.
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191203141515.3597631-2-boris.brezillon@collabora.com
This patch adds atomic variants for all of
pre_enable/enable/disable/post_disable bridge functions. These will be
called from the appropriate atomic helper functions. If the bridge
driver doesn't implement the atomic version of the function, we will
fall back to the vanilla implementation.
Note that some drivers call drm_bridge_disable directly, and these cases
are not covered. It's up to the driver to decide whether to implement
both atomic_disable and disable, or if it's not necessary.
Changes in v3:
- Added to the patchset
Changes in v4:
- Fix up docbook references (Daniel)
Changes in v5:
- None
Link to v3: https://patchwork.freedesktop.org/patch/msgid/20190502194956.218441-4-sean@poorly.run
Link to v4: https://patchwork.freedesktop.org/patch/msgid/20190508160920.144739-4-sean@poorly.run
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190611160844.257498-4-sean@poorly.run
The mode and ajusted_mode passed to the bridge .mode_set() operation
should never be modified by the bridge (and are not in any of the
existing bridge drivers). Make them const to make this clear.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Introduce a new helper function which calls mode_valid() callback
for all bridges in an encoder chain.
Signed-off-by: Jose Abreu <joabreu@synopsys.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Carlos Palminha <palminha@synopsys.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Dave Airlie <airlied@linux.ie>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: Archit Taneja <architt@codeaurora.org>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/36bd5e054496ad3c9c71f1ffe204f28533f55f1e.1495720737.git.joabreu@synopsys.com
I just learned that &struct_name.member_name works and looks pretty
even. It doesn't (yet) link to the member directly though, which would
be really good for big structures or vfunc tables (where the
per-member kerneldoc tends to be long).
Also some minor drive-by polish where it makes sense, I read a lot
of docs ...
Cc: Archit Taneja <architt@codeaurora.org>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Archit Taneja <architt@codeaurora.org>
[danvet: Remove spurious hunk that Archit spotted.]
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1483044517-5770-13-git-send-email-daniel.vetter@ffwll.ch
sed -e 's/\( \* .*\)struct &\([_a-z]*\)/\1\&struct \2/' -i
Originally I wasnt a friend of this style because I thought a
line-break between the "&struct" and "foo" part would break it. But a
quick test shows that " * &struct \n * foo\n" works pefectly well with
current kernel-doc. So time to mass-apply these changes!
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1483044517-5770-6-git-send-email-daniel.vetter@ffwll.ch
Instead of linking encoders and bridges in every driver (and getting it
wrong half of the time, as many drivers forget to set the drm_bridge
encoder pointer), do so in core code. The drm_bridge_attach() function
needs the encoder and optional previous bridge to perform that task,
update all the callers.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Stefan Agner <stefan@agner.ch> # For DCU
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com> # For atmel-hlcdc
Acked-by: Vincent Abriou <vincent.abriou@st.com> # For STI
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com> # For sun4i
Acked-by: Xinliang Liu <z.liuxinliang@hisilicon.com> # For hisilicon
Acked-by: Jyri Sarha <jsarha@ti.com> # For tilcdc
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Archit Taneja <architt@codeaurora.org>
Link: http://patchwork.freedesktop.org/patch/msgid/1481709550-29226-4-git-send-email-laurent.pinchart+renesas@ideasonboard.com
Up to now, once a bridge has been attached to a DRM device, it cannot
be undone.
In particular you couldn't rmmod/insmod a DRM driver that uses a bridge,
because the bridge would remain bound to the first (dead) driver instance.
This patch fixes this by introducing drm_encoder_detach() and a ->detach
callback in drm_bridge_funcs for the bridge to be notified about detaches.
It's DRM/KMS driver responsibility to call drm_encoder_detach().
While adding the bridge detach callback, with its kerneldoc, I also added
kerneldoc for attach callback.
Few other kerneldocs fixes around there are included.
Suggested-by: Daniel Vetter <daniel@ffwll.ch>
Suggested-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Andrea Merello <andrea.merello@gmail.com>
Cc: Archit Taneja <architt@codeaurora.org>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Archit Taneja <architt@codeaurora.org>
Link: http://patchwork.freedesktop.org/patch/msgid/1472115874-6219-1-git-send-email-andrea.merello@gmail.com
Just fallout from switching from asciidoc to sphinx/rst.
v2: Found more. Also s/\//#/ in the vgpu ascii-art - sphinx treats
those as comments and switch to variable-width, which wreaks the
layout.
v3: Undo some of the hacks, rebasing onto latest version of Jani's
series fixed it.
Acked-by: Liviu Dudau <Liviu.Dudau@arm.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Instead of forcing bridges to implement empty callbacks make them all
optional.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Especially document the assumptions and semantics of the callbacks
carefully. Just a warm-up excercise really.
v2: Spelling fixes (Eric).
v3: Consolidate more with existing docs:
- Remove the overview section explaining the bridge funcs, that's
now all in the drm_bridge_funcs kerneldoc in much more detail.
- Use & to reference structs so that kerneldoc automatically inserts
hyperlinks.
v4: Review from Thierry.
Cc: Eric Anholt <eric@anholt.net>
Cc: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Archit Taneja <architt@codeaurora.org> (v3)
Link: http://patchwork.freedesktop.org/patch/msgid/1449218769-16577-7-git-send-email-daniel.vetter@ffwll.ch
Reviewed-by: Thierry Reding <treding@nvidia.com>
Add DOC sections giving an overview of drm_bridge and how to fill up the
drm_bridge_funcs ops. Add these to drm.tpml in DocBook.
Add headerdocs for funcs in drm_bridge.c that don't have them yet.
Signed-off-by: Archit Taneja <architt@codeaurora.org>
[danvet: Amend kerneldoc as discussed with Archit.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Allow drm_bridge objects to link to each other in order to form an encoder
chain. The requirement for creating a chain of bridges comes because the
MSM drm driver uses up its encoder and bridge objects for blocks within
the SoC itself. There isn't anything left to use if the SoC display output
is connected to an external encoder IC. Having an additional bridge
connected to the existing bridge helps here. In general, it is possible for
platforms to have multiple devices between the encoder and the
connector/panel that require some sort of configuration.
We create drm bridge helper functions corresponding to each op in
'drm_bridge_funcs'. These helpers call the corresponding
'drm_bridge_funcs' op for the entire chain of bridges. These helpers are
used internally by drm_atomic_helper.c and drm_crtc_helper.c.
The drm_bridge_enable/pre_enable helpers execute enable/pre_enable ops of
the bridge closet to the encoder, and proceed until the last bridge in the
chain is enabled. The same holds for drm_bridge_mode_set/mode_fixup
helpers. The drm_bridge_disable/post_disable helpers disable the last
bridge in the chain first, and proceed until the first bridge in the chain
is disabled.
drm_bridge_attach() remains the same. As before, the driver calling this
function should make sure it has set the links correctly. The order in
which the bridges are connected to each other determines the order in which
the calls are made. One requirement is that every bridge in the chain
should point the parent encoder object. This is required since bridge
drivers expect a valid encoder pointer in drm_bridge. For example, consider
a chain where an encoder's output is connected to bridge1, and bridge1's
output is connected to bridge2:
/* Like before, attach bridge to an encoder */
bridge1->encoder = encoder;
ret = drm_bridge_attach(dev, bridge1);
..
/*
* set the first bridge's 'next' bridge to bridge2, set its encoder
* as bridge1's encoder
*/
bridge1->next = bridge2
bridge2->encoder = bridge1->encoder;
ret = drm_bridge_attach(dev, bridge2);
...
...
This method of bridge chaining isn't intrusive and existing drivers that
use drm_bridge will behave the same way as before. The bridge helpers also
cleans up the atomic and crtc helper files a bit.
Reviewed-by: Jani Nikula <jani.nikula@linux.intel.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
../drivers/gpu/drm/drm_vm.c:405:6: warning: symbol 'drm_vm_open_locked' was not declared. Should it be static?
../drivers/gpu/drm/drm_vm.c:431:6: warning: symbol 'drm_vm_close_locked' was not declared. Should it be static?
../drivers/gpu/drm/drm_vm.c:681:5: warning: symbol 'drm_vma_info' was not declared. Should it be static?
../drivers/gpu/drm/drm_pci.c:146:5: warning: symbol 'drm_pci_set_unique' was not declared. Should it be static?
../drivers/gpu/drm/drm_pci.c:216:5: warning: symbol 'drm_irq_by_busid' was not declared. Should it be static?
../drivers/gpu/drm/drm_info.c:47:5: warning: symbol 'drm_name_info' was not declared. Should it be static?
../drivers/gpu/drm/drm_info.c:72:5: warning: symbol 'drm_vm_info' was not declared. Should it be static?
../drivers/gpu/drm/drm_info.c:116:5: warning: symbol 'drm_bufs_info' was not declared. Should it be static?
../drivers/gpu/drm/drm_info.c:159:5: warning: symbol 'drm_clients_info' was not declared. Should it be static?
../drivers/gpu/drm/drm_info.c:209:5: warning: symbol 'drm_gem_name_info' was not declared. Should it be static?
../drivers/gpu/drm/drm_ioc32.c:1019:20: warning: symbol 'drm_compat_ioctls' was not declared. Should it be static?
../drivers/gpu/drm/drm_bridge.c:52:12: warning: function 'drm_bridge_attach' with external linkage has definition
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Currently, third party bridge drivers(ptn3460) are dependent
on the corresponding encoder driver init, since bridge driver
needs a drm_device pointer to finish drm initializations.
The encoder driver passes the drm_device pointer to the
bridge driver. Because of this dependency, third party drivers
like ptn3460 doesn't adhere to the driver model.
In this patch, we reframe the bridge registration framework
so that bridge initialization is split into 2 steps, and
bridge registration happens independent of drm flow:
--Step 1: gather all the bridge settings independent of drm and
add the bridge onto a global list of bridges.
--Step 2: when the encoder driver is probed, call drm_bridge_attach
for the corresponding bridge so that the bridge receives
drm_device pointer and continues with connector and other
drm initializations.
The old set of bridge helpers are removed, and a set of new helpers
are added to accomplish the 2 step initialization.
The bridge devices register themselves onto global list of bridges
when they get probed by calling "drm_bridge_add".
The parent encoder driver waits till the bridge is available
in the lookup table(by calling "of_drm_find_bridge") and then
continues with its initialization.
The encoder driver should also call "drm_bridge_attach" to pass
on the drm_device to the bridge object.
drm_bridge_attach inturn calls "bridge->funcs->attach" so that
bridge can continue with drm related initializations.
Signed-off-by: Ajay Kumar <ajaykumar.rs@samsung.com>
Acked-by: Inki Dae <inki.dae@samsung.com>
Tested-by: Rahul Sharma <rahul.sharma@samsung.com>
Tested-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Tested-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Tested-by: Sjoerd Simons <sjoerd.simons@collabora.co.uk>
Signed-off-by: Thierry Reding <treding@nvidia.com>
