[ Upstream commit 4ecff954c3 ]
A problem about insmod megachips-stdpxxxx-ge-b850v3-fw.ko failed is
triggered with the following log given:
[ 4497.981497] Error: Driver 'stdp4028-ge-b850v3-fw' is already registered, aborting...
insmod: ERROR: could not insert module megachips-stdpxxxx-ge-b850v3-fw.ko: Device or resource busy
The reason is that stdpxxxx_ge_b850v3_init() returns i2c_add_driver()
directly without checking its return value, if i2c_add_driver() failed,
it returns without calling i2c_del_driver() on the previous i2c driver,
resulting the megachips-stdpxxxx-ge-b850v3-fw can never be installed
later.
A simple call graph is shown as below:
stdpxxxx_ge_b850v3_init()
i2c_add_driver(&stdp4028_ge_b850v3_fw_driver)
i2c_add_driver(&stdp2690_ge_b850v3_fw_driver)
i2c_register_driver()
driver_register()
bus_add_driver()
priv = kzalloc(...) # OOM happened
# return without delete stdp4028_ge_b850v3_fw_driver
Fix by calling i2c_del_driver() on stdp4028_ge_b850v3_fw_driver when
i2c_add_driver() returns error.
Fixes: fcfa0ddc18 ("drm/bridge: Drivers for megachips-stdpxxxx-ge-b850v3-fw (LVDS-DP++)")
Signed-off-by: Yuan Can <yuancan@huawei.com>
Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>
Tested-by: Ian Ray <ian.ray@ge.com>
Signed-off-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20221108091226.114524-1-yuancan@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 9a0cdcd664 ]
adv7533 bridge tries to dynamically switch lanes based on the
mode by detaching and attaching the mipi dsi device.
This approach is incorrect because this method of dynamic switch of
detaching and attaching the mipi dsi device also results in removing
and adding the component which is not necessary.
This approach is also prone to deadlocks. So for example, on the
db410c whenever this path is executed with lockdep enabled,
this results in a deadlock due to below ordering of locks.
-> #1 (crtc_ww_class_acquire){+.+.}-{0:0}:
lock_acquire+0x6c/0x90
drm_modeset_acquire_init+0xf4/0x150
drmm_mode_config_init+0x220/0x770
msm_drm_bind+0x13c/0x654
try_to_bring_up_aggregate_device+0x164/0x1d0
__component_add+0xa8/0x174
component_add+0x18/0x2c
dsi_dev_attach+0x24/0x30
dsi_host_attach+0x98/0x14c
devm_mipi_dsi_attach+0x38/0xb0
adv7533_attach_dsi+0x8c/0x110
adv7511_probe+0x5a0/0x930
i2c_device_probe+0x30c/0x350
really_probe.part.0+0x9c/0x2b0
__driver_probe_device+0x98/0x144
driver_probe_device+0xac/0x14c
__device_attach_driver+0xbc/0x124
bus_for_each_drv+0x78/0xd0
__device_attach+0xa8/0x1c0
device_initial_probe+0x18/0x24
bus_probe_device+0xa0/0xac
deferred_probe_work_func+0x90/0xd0
process_one_work+0x28c/0x6b0
worker_thread+0x240/0x444
kthread+0x110/0x114
ret_from_fork+0x10/0x20
-> #0 (component_mutex){+.+.}-{3:3}:
__lock_acquire+0x1280/0x20ac
lock_acquire.part.0+0xe0/0x230
lock_acquire+0x6c/0x90
__mutex_lock+0x84/0x400
mutex_lock_nested+0x3c/0x70
component_del+0x34/0x170
dsi_dev_detach+0x24/0x30
dsi_host_detach+0x20/0x64
mipi_dsi_detach+0x2c/0x40
adv7533_mode_set+0x64/0x90
adv7511_bridge_mode_set+0x210/0x214
drm_bridge_chain_mode_set+0x5c/0x84
crtc_set_mode+0x18c/0x1dc
drm_atomic_helper_commit_modeset_disables+0x40/0x50
msm_atomic_commit_tail+0x1d0/0x6e0
commit_tail+0xa4/0x180
drm_atomic_helper_commit+0x178/0x3b0
drm_atomic_commit+0xa4/0xe0
drm_client_modeset_commit_atomic+0x228/0x284
drm_client_modeset_commit_locked+0x64/0x1d0
drm_client_modeset_commit+0x34/0x60
drm_fb_helper_lastclose+0x74/0xcc
drm_lastclose+0x3c/0x80
drm_release+0xfc/0x114
__fput+0x70/0x224
____fput+0x14/0x20
task_work_run+0x88/0x1a0
do_exit+0x350/0xa50
do_group_exit+0x38/0xa4
__wake_up_parent+0x0/0x34
invoke_syscall+0x48/0x114
el0_svc_common.constprop.0+0x60/0x11c
do_el0_svc+0x30/0xc0
el0_svc+0x58/0x100
el0t_64_sync_handler+0x1b0/0x1bc
el0t_64_sync+0x18c/0x190
Due to above reasons, remove the dynamic lane switching
code from adv7533 bridge chip and filter out the modes
which would need different number of lanes as compared
to the initialization time using the mode_valid callback.
This can be potentially re-introduced by using the pre_enable()
callback but this needs to be evaluated first whether such an
approach will work so this will be done with a separate change.
changes since RFC:
- Fix commit text and add TODO comment
changes in v2:
- Fix checkpatch formatting errors
Fixes: 62b2f026cd ("drm/bridge: adv7533: Change number of DSI lanes dynamically")
Closes: https://gitlab.freedesktop.org/drm/msm/-/issues/16
Suggested-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Reviewed-by: Robert Foss <robert.foss@linaro.org>
Link: https://lore.kernel.org/r/1661797363-7564-1-git-send-email-quic_abhinavk@quicinc.com
Signed-off-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/1665522649-3423-1-git-send-email-quic_abhinavk@quicinc.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d3d6b1bf85 ]
Cheap monitors sometimes advertise YUV modes they don't really have
(HDMI specification mandates YUV support so even monitors without actual
support will often wrongfully advertise it) which results in YUV matches
and user forum complaints of a red tint to light colour display areas in
common desktop environments.
Moving the default RGB fall-back before YUV selection results in RGB
mode matching in most cases, reducing complaints.
Fixes: 6c3c719936 ("drm/bridge: synopsys: dw-hdmi: add bus format negociation")
Signed-off-by: Guillaume BRUN <the.cheaterman@gmail.com>
Tested-by: Christian Hewitt <christianshewitt@gmail.com>
Reviewed-by: Robert Foss <robert.foss@linaro.org>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20221116143523.2126-1-the.cheaterman@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8c11586450 ]
According to the description in ti-sn65dsi86's datasheet:
CHA_HSYNC_POLARITY:
0 = Active High Pulse. Synchronization signal is high for the sync
pulse width. (default)
1 = Active Low Pulse. Synchronization signal is low for the sync
pulse width.
CHA_VSYNC_POLARITY:
0 = Active High Pulse. Synchronization signal is high for the sync
pulse width. (Default)
1 = Active Low Pulse. Synchronization signal is low for the sync
pulse width.
We should only set these bits when the polarity is negative.
Fixes: a095f15c00 ("drm/bridge: add support for sn65dsi86 bridge driver")
Signed-off-by: Qiqi Zhang <eddy.zhang@rock-chips.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20221125104558.84616-1-eddy.zhang@rock-chips.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit da09daf881 ]
There are two events that signal a real change of the link state: HPD going
high means the sink is newly connected or wants the source to re-read the
EDID, RX sense going low is a indication that the link has been disconnected.
Ignore the other two events that also trigger interrupts, but don't need
immediate attention: HPD going low does not necessarily mean the link has
been lost and should not trigger a immediate read of the status. RX sense
going high also does not require a detect cycle, as HPD going high is the
right point in time to read the EDID.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com> (v1)
Reviewed-by: Robert Foss <robert.foss@linaro.org>
Signed-off-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220826185733.3213248-1-l.stach@pengutronix.de
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 1ff673333d ]
When removing the module we will get the following warning:
[ 31.911505] i2c-core: driver [stdp2690-ge-b850v3-fw] unregistered
[ 31.912484] general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN PTI
[ 31.913338] KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
[ 31.915280] RIP: 0010:drm_bridge_remove+0x97/0x130
[ 31.921825] Call Trace:
[ 31.922533] stdp4028_ge_b850v3_fw_remove+0x34/0x60 [megachips_stdpxxxx_ge_b850v3_fw]
[ 31.923139] i2c_device_remove+0x181/0x1f0
The two bridges (stdp2690, stdp4028) do not probe at the same time, so
the driver does not call ge_b850v3_resgiter() when probing, causing the
driver to try to remove the object that has not been initialized.
Fix this by checking whether both the bridges are probed.
Fixes: 11632d4aa2 ("drm/bridge: megachips: Ensure both bridges are probed before registration")
Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
Signed-off-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220830073450.1897020-1-zheyuma97@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit cc62d98bd5 ]
This reverts commit 211f276ed3.
For quite some time, core DRM helpers already ensure that any relevant
connectors/CRTCs/etc. are disabled, as well as their associated
components (e.g., bridges) when suspending the system. Thus,
analogix_dp_bridge_{enable,disable}() already get called, which in turn
call drm_panel_{prepare,unprepare}(). This makes these drm_panel_*()
calls redundant.
Besides redundancy, there are a few problems with this handling:
(1) drm_panel_{prepare,unprepare}() are *not* reference-counted APIs and
are not in general designed to be handled by multiple callers --
although some panel drivers have a coarse 'prepared' flag that mitigates
some damage, at least. So at a minimum this is redundant and confusing,
but in some cases, this could be actively harmful.
(2) The error-handling is a bit non-standard. We ignored errors in
suspend(), but handled errors in resume(). And recently, people noticed
that the clk handling is unbalanced in error paths, and getting *that*
right is not actually trivial, given the current way errors are mostly
ignored.
(3) In the particular way analogix_dp_{suspend,resume}() get used (e.g.,
in rockchip_dp_*(), as a late/early callback), we don't necessarily have
a proper PM relationship between the DP/bridge device and the panel
device. So while the DP bridge gets resumed, the panel's parent device
(e.g., platform_device) may still be suspended, and so any prepare()
calls may fail.
So remove the superfluous, possibly-harmful suspend()/resume() handling
of panel state.
Fixes: 211f276ed3 ("drm: bridge: analogix/dp: add panel prepare/unprepare in suspend/resume time")
Link: https://lore.kernel.org/all/Yv2CPBD3Picg%2FgVe@google.com/
Signed-off-by: Brian Norris <briannorris@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220822180729.1.I8ac5abe3a4c1c6fd5c061686c6e883c22f69022c@changeid
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 9030a9e571 upstream.
Per toshiba,tc358767.yaml DT binding document, port@2 the output (e)DP
port is optional. In case this port is not described in DT, the bridge
driver operates in DPI-to-DP mode. The drm_of_find_panel_or_bridge()
call in tc_probe_edp_bridge_endpoint() returns -ENODEV in case port@2
is not present in DT and this specific return value is incorrectly
propagated outside of tc_probe_edp_bridge_endpoint() function. All
other error values must be propagated and are propagated correctly.
Return 0 in case the port@2 is missing instead, that reinstates the
original behavior before the commit this patch fixes.
Fixes: 8478095a8c ("drm/bridge: tc358767: Move (e)DP bridge endpoint parsing into dedicated function")
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Jonas Karlman <jonas@kwiboo.se>
Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Marek Vasut <marex@denx.de>
Cc: Maxime Ripard <maxime@cerno.tech>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Robert Foss <robert.foss@linaro.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20220428213132.447890-1-marex@denx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 21779cc21c ]
The next call to sii8620_burst_get_tx_buf will result in off-by-one
When ctx->burst.tx_count + size == ARRAY_SIZE(ctx->burst.tx_buf). The same
thing happens in sii8620_burst_get_rx_buf.
This patch also change tx_count and tx_buf to rx_count and rx_buf in
sii8620_burst_get_rx_buf. It is unreasonable to check tx_buf's size and
use rx_buf.
Fixes: e19e9c692f ("drm/bridge/sii8620: add support for burst eMSC transmissions")
Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>
Signed-off-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220518065856.18936-1-hbh25y@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 9cc4853e47 ]
Commit 680532c50b ("drm: adv7511: Add support for
i2c_new_secondary_device") allows a device tree node to override
the default addresses of the secondary i2c devices. This is useful
for solving address conflicts on the i2c bus.
In adv7511_init_cec_regmap() the new i2c address of cec device is
read from device tree and immediately accessed, well before it is
written in the proper register to override the default address.
This can cause an i2c error during probe and a consequent probe
failure.
Once the new i2c address is read from the device tree, override
the default address before any attempt to access the cec.
Tested with adv7533 and stm32mp157f.
Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
Fixes: 680532c50b ("drm: adv7511: Add support for i2c_new_secondary_device")
Reviewed-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
Signed-off-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220607213144.427177-1-antonio.borneo@foss.st.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit ca871659ec upstream.
Most eDP panel functions only work correctly when the panel is not in
self-refresh. In particular, analogix_dp_bridge_disable() tends to hit
AUX channel errors if the panel is in self-refresh.
Given the above, it appears that so far, this driver assumes that we are
never in self-refresh when it comes time to fully disable the bridge.
Prior to commit 846c7dfc11 ("drm/atomic: Try to preserve the crtc
enabled state in drm_atomic_remove_fb, v2."), this tended to be true,
because we would automatically disable the pipe when framebuffers were
removed, and so we'd typically disable the bridge shortly after the last
display activity.
However, that is not guaranteed: an idle (self-refresh) display pipe may
be disabled, e.g., when switching CRTCs. We need to exit PSR first.
Stable notes: this is definitely a bugfix, and the bug has likely
existed in some form for quite a while. It may predate the "PSR helpers"
refactor, but the code looked very different before that, and it's
probably not worth rewriting the fix.
Cc: <stable@vger.kernel.org>
Fixes: 6c836d965b ("drm/rockchip: Use the helpers for PSR")
Signed-off-by: Brian Norris <briannorris@chromium.org>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220228122522.v2.1.I161904be17ba14526f78536ccd78b85818449b51@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 1528038385 ]
When the dw-hdmi bridge is in first place of the bridge chain, this
means there is no way to select an input format of the dw-hdmi HW
component.
Since introduction of display-connector, negotiation was broken since
the dw-hdmi negotiation code only worked when the dw-hdmi bridge was
in last position of the bridge chain or behind another bridge also
supporting input & output format negotiation.
Commit 7cd70656d1 ("drm/bridge: display-connector: implement bus fmts callbacks")
was introduced to make negotiation work again by making display-connector
act as a pass-through concerning input & output format negotiation.
But in the case where the dw-hdmi is single in the bridge chain, for
example on Renesas SoCs, with the display-connector bridge the dw-hdmi
is no more single, breaking output format.
Reported-by: Biju Das <biju.das.jz@bp.renesas.com>
Bisected-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
Tested-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
Fixes: 6c3c719936 ("drm/bridge: synopsys: dw-hdmi: add bus format negociation")
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
[narmstrong: add proper fixes commit]
Reviewed-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220204143337.89221-1-narmstrong@baylibre.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit c4c6ef2295 upstream.
Prior to commit 6c836d965b ("drm/rockchip: Use the helpers for PSR"),
"PSR exit" used non-blocking analogix_dp_send_psr_spd(). The refactor
started using the blocking variant, for a variety of reasons -- quoting
Sean Paul's potentially-faulty memory:
"""
- To avoid racing a subsequent PSR entry (if exit takes a long time)
- To avoid racing disable/modeset
- We're not displaying new content while exiting PSR anyways, so there
is minimal utility in allowing frames to be submitted
- We're lying to userspace telling them frames are on the screen when
we're just dropping them on the floor
"""
However, I'm finding that this blocking transition is causing upwards of
60+ ms of unneeded latency on PSR-exit, to the point that initial cursor
movements when leaving PSR are unbearably jumpy.
It turns out that we need to meet in the middle somewhere: Sean is right
that we were "lying to userspace" with a non-blocking PSR-exit, but the
new blocking behavior is also waiting too long:
According to the eDP specification, the sink device must support PSR
entry transitions from both state 4 (ACTIVE_RESYNC) and state 0
(INACTIVE). It also states that in ACTIVE_RESYNC, "the Sink device must
display the incoming active frames from the Source device with no
visible glitches and/or artifacts."
Thus, for our purposes, we only need to wait for ACTIVE_RESYNC before
moving on; we are ready to display video, and subsequent PSR-entry is
safe.
Tested on a Samsung Chromebook Plus (i.e., Rockchip RK3399 Gru Kevin),
where this saves about 60ms of latency, for PSR-exit that used to
take about 80ms.
Fixes: 6c836d965b ("drm/rockchip: Use the helpers for PSR")
Cc: <stable@vger.kernel.org>
Cc: Zain Wang <wzz@rock-chips.com>
Cc: Tomasz Figa <tfiga@chromium.org>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Brian Norris <briannorris@chromium.org>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20211103135112.v3.1.I67612ea073c3306c71b46a87be894f79707082df@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 3f2532d65a ]
The current ELD handling takes the internal connector ELD buffer and
shares it to the I2S and AHB sub-driver.
But with DRM_BRIDGE_ATTACH_NO_CONNECTOR, the connector is created
elsewhere (or not), and an eventual connector is known only
if the bridge chain up to a connector is enabled.
The current dw-hdmi code gets the current connector from
atomic_enable() so use the already stored connector pointer and
replace the buffer pointer with a callback returning the current
connector ELD buffer.
Since a connector is not always available, either pass an empty
ELD to the alsa HDMI driver or don't call snd_pcm_hw_constraint_eld()
in AHB driver.
Reported-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
[narmstrong: fixed typo in commit log]
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211029135947.3022875-1-narmstrong@baylibre.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit cc5f7e2fcb upstream.
On the SII9022, the IOVCC and CVCC12 supplies must reach the correct
voltage before the reset sequence is initiated. On most boards, this
assumption is true at boot-up, so initialization succeeds.
However, when we try to initialize the chip with incorrect supply
voltages, it will not respond to I2C requests. sii902x_probe() fails
with -ENXIO.
To resolve this, look for the "iovcc" and "cvcc12" regulators, and
make sure they are enabled before starting the reset sequence. If
these supplies are not available in devicetree, then they will default
to dummy-regulator. In that case everything will work like before.
This was observed on a STM32MP157C-DK2 booting in u-boot falcon mode.
On this board, the supplies would be set by the second stage
bootloader, which does not run in falcon mode.
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
[Fix checkpatch warnings]
Link: https://patchwork.freedesktop.org/patch/msgid/20201020221501.260025-2-mr.nuke.me@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It has been observed that resetting force in the detect function can
result in the PHY being powered down in response to hot-plug detect
being asserted, even when the HDMI connector is forced on.
Enabling debug messages and adding a call to dump_stack() in
dw_hdmi_phy_power_off() shows the following in dmesg:
[ 160.637413] dwhdmi-rockchip ff940000.hdmi: EVENT=plugin
[ 160.637433] dwhdmi-rockchip ff940000.hdmi: PHY powered down in 0 iterations
Call trace:
dw_hdmi_phy_power_off
dw_hdmi_phy_disable
dw_hdmi_update_power
dw_hdmi_detect
dw_hdmi_connector_detect
drm_helper_probe_detect_ctx
drm_helper_hpd_irq_event
dw_hdmi_irq
irq_thread_fn
irq_thread
kthread
ret_from_fork
Fixes: 381f05a7a8 ("drm: bridge/dw_hdmi: add connector mode forcing")
Signed-off-by: Jonathan Liu <net147@gmail.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201031081747.372599-1-net147@gmail.com