[ Upstream commit bf3f5e98559360661a3d2af340d46522512c0b00 ]
Fix build warning if drm_panel.h is built with CONFIG_OF=n or
CONFIG_DRM_PANEL=n and included without the prerequisite err.h:
./include/drm/drm_panel.h: In function ‘of_drm_find_panel’:
./include/drm/drm_panel.h:203:9: error: implicit declaration of function ‘ERR_PTR’ [-Werror=implicit-function-declaration]
return ERR_PTR(-ENODEV);
^~~~~~~
./include/drm/drm_panel.h:203:9: error: returning ‘int’ from a function with return type ‘struct drm_panel *’ makes pointer from integer without a cast [-Werror=int-conversion]
return ERR_PTR(-ENODEV);
^~~~~~~~~~~~~~~~
Fixes: 5fa8e4a221 ("drm/panel: Make of_drm_find_panel() return an ERR_PTR() instead of NULL")
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Sean Paul <sean@poorly.run>
Cc: Boris Brezillon <bbrezillon@kernel.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190718161507.2047-2-sam@ravnborg.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
This reverts commit 0c08754b59.
commit 0c08754b59
("drm/panel: Add device_link from panel device to DRM device")
creates a circular dependency under these circumstances:
1. The panel depends on dsi-host because it is MIPI-DSI child
device.
2. dsi-host depends on the drm parent device (connector->dev->dev)
this should be allowed.
3. drm parent dev (connector->dev->dev) depends on the panel
after this patch.
This makes the dependency circular and while it appears it
does not affect any in-tree drivers (they do not seem to have
dsi hosts depending on the same parent device) this does not
seem right.
As noted in a response from Andrzej Hajda, the intent is
likely to make the panel dependent on the DRM device
(connector->dev) not its parent. But we have no way of
doing that since the DRM device doesn't contain any
struct device on its own (arguably it should).
Revert this until a proper approach is figured out.
Cc: Jyri Sarha <jsarha@ti.com>
Cc: Eric Anholt <eric@anholt.net>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20180927124130.9102-1-linus.walleij@linaro.org
Right now, the DRM panel logic returns NULL when a panel pointing to
the passed OF node is not present in the list of registered panels.
Most drivers interpret this NULL value as -EPROBE_DEFER, but we are
about to modify the semantic of of_drm_find_panel() and let the
framework return -ENODEV when the device node we're pointing to has
a status property that is not equal to "okay" or "ok".
Let's first patch the of_drm_find_panel() implementation to return
ERR_PTR(-EPROBE_DEFER) instead of NULL and patch all callers to replace
the '!panel' check by an 'IS_ERR(panel)' one.
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180509130042.9435-2-boris.brezillon@bootlin.com
Add device_link from panel device (supplier) to DRM device (consumer)
when drm_panel_attach() is called. This patch should protect the master
DRM driver if an attached panel driver unbinds while it is in use. The
device_link should make sure the DRM device is unbound before the panel
driver becomes unavailable.
The device_link is removed when drm_panel_detach() is called. The
drm_panel_detach() should be called by the consumer DRM driver, not the
panel driver, otherwise both drivers are racing to delete the same link.
Signed-off-by: Jyri Sarha <jsarha@ti.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/b53584fd988d045c13de22d81825395b0ae0aad7.1524727888.git.jsarha@ti.com
For drm_of_find_panel_or_bridge() added in the next commit, an empty
version of of_drm_find_panel is needed for !CONFIG_DRM_PANEL.
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
The argument is never modified by the function, make it const.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Write more complete kerneldoc comments for the DRM panel API and
integrate the helpers in the DRM DocBook reference.
Signed-off-by: Thierry Reding <treding@nvidia.com>drm/panel: Add helper for simple panel connector
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20160506140137.GA4641@ulmo.ba.sec
Many panel data sheets, additionally to typical values, list allowed
ranges for timings such as hsync/vsync lengths, porches, and the pixel
clock rate. These can be stored in a struct display_timing, to be used
by an encoder mode_fixup callback to clamp user provided timing values
or to validate workarounds for clock source limitations.
This patch adds a new drm_panel_funcs callback that returns the panel's
available display_timing entries.
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Add a convenience wrapper for the struct drm_panel_funcs' .get_modes()
function so that not every driver needs to check that the panel driver
implements the function before calling it.
Signed-off-by: Ajay Kumar <ajaykumar.rs@samsung.com>
[treding: extract from larger patch, commit message]
Signed-off-by: Thierry Reding <treding@nvidia.com>
Panels often require an initialization sequence that consists of three
steps: a) powering up the panel, b) starting transmission of video data
and c) enabling the panel (e.g. turn on backlight). This is usually
necessary to avoid visual glitches at the beginning of video data
transmission.
Similarly, the shutdown sequence is typically done in three steps as
well: a) disable the panel (e.g. turn off backlight), b) cease video
data transmission and c) power down the panel.
Currently drivers can only implement .enable() and .disable() functions,
which is not enough to implement the above sequences. This commit adds a
second pair of functions, .prepare() and .unprepare() to allow more
fine-grained control over when the above steps are performed.
Signed-off-by: Ajay Kumar <ajaykumar.rs@samsung.com>
[treding: rewrite changelog, add kerneldoc]
Signed-off-by: Thierry Reding <treding@nvidia.com>
Add a very simple framework to register and lookup panels. Panel drivers
can initialize a DRM panel and register it with the framework, allowing
them to be retrieved and used by display drivers. Currently only support
for DPMS and obtaining panel modes is provided. However it should be
sufficient to enable a large number of panels. The framework should also
be easily extensible to support more sophisticated kinds of panels such
as DSI.
The framework hasn't been tied into the DRM core, even though it should
be easily possible to do so if that's what we want. In the current
implementation, display drivers can simple make use of it to retrieve a
panel, obtain its modes and control its DPMS mode.
Note that this is currently only tested on systems that boot from a
device tree. No glue code has been written yet for systems that use
platform data, but it should be easy to add.
Signed-off-by: Thierry Reding <treding@nvidia.com>
