linux-stable.git/drivers/gpu/drm/bridge, branch v4.19.321

drm/bridge: analogix_dp: properly handle zero sized AUX transactions

2024-08-19T03:32:16+00:00

commit e82290a2e0e8ec5e836ecad1ca025021b3855c2d upstream.

Address only transactions without any data are valid and should not
be flagged as short transactions. Simply return the message size when
no transaction errors occured.

CC: stable@vger.kernel.org
Signed-off-by: Lucas Stach 
Reviewed-by: Robert Foss 
Signed-off-by: Robert Foss 
Link: https://patchwork.freedesktop.org/patch/msgid/20240318203925.2837689-1-l.stach@pengutronix.de
Signed-off-by: Greg Kroah-Hartman

drm/bridge/panel: Fix runtime warning on panel bridge release

2024-07-05T07:00:24+00:00

[ Upstream commit ce62600c4dbee8d43b02277669dd91785a9b81d9 ]

Device managed panel bridge wrappers are created by calling to
drm_panel_bridge_add_typed() and registering a release handler for
clean-up when the device gets unbound.

Since the memory for this bridge is also managed and linked to the panel
device, the release function should not try to free that memory.
Moreover, the call to devm_kfree() inside drm_panel_bridge_remove() will
fail in this case and emit a warning because the panel bridge resource
is no longer on the device resources list (it has been removed from
there before the call to release handlers).

Fixes: 67022227ffb1 ("drm/bridge: Add a devm_ allocator for panel bridge.")
Signed-off-by: Adam Miotk 
Signed-off-by: Maxime Ripard 
Link: https://patchwork.freedesktop.org/patch/msgid/20240610102739.139852-1-adam.miotk@arm.com
Signed-off-by: Sasha Levin

drm/bridge: nxp-ptn3460: simplify some error checking

2024-02-23T07:12:43+00:00

commit 28d3d0696688154cc04983f343011d07bf0508e4 upstream.

The i2c_master_send/recv() functions return negative error codes or
they return "len" on success.  So the error handling here can be written
as just normal checks for "if (ret < 0) return ret;".  No need to
complicate things.

Btw, in this code the "len" parameter can never be zero, but even if
it were, then I feel like this would still be the best way to write it.

Fixes: 914437992876 ("drm/bridge: nxp-ptn3460: fix i2c_master_send() error checking")
Suggested-by: Neil Armstrong 
Signed-off-by: Dan Carpenter 
Reviewed-by: Robert Foss 
Signed-off-by: Robert Foss 
Link: https://patchwork.freedesktop.org/patch/msgid/04242630-42d8-4920-8c67-24ac9db6b3c9@moroto.mountain
Signed-off-by: Greg Kroah-Hartman

drm/bridge: nxp-ptn3460: fix i2c_master_send() error checking

2024-02-23T07:12:43+00:00

commit 914437992876838662c968cb416f832110fb1093 upstream.

The i2c_master_send/recv() functions return negative error codes or the
number of bytes that were able to be sent/received.  This code has
two problems.  1)  Instead of checking if all the bytes were sent or
received, it checks that at least one byte was sent or received.
2) If there was a partial send/receive then we should return a negative
error code but this code returns success.

Fixes: a9fe713d7d45 ("drm/bridge: Add PTN3460 bridge driver")
Cc: stable@vger.kernel.org
Signed-off-by: Dan Carpenter 
Reviewed-by: Robert Foss 
Signed-off-by: Robert Foss 
Link: https://patchwork.freedesktop.org/patch/msgid/0cdc2dce-ca89-451a-9774-1482ab2f4762@moroto.mountain
Signed-off-by: Greg Kroah-Hartman

drm: adv7511: Fix low refresh rate register for ADV7533/5

2023-09-23T08:48:04+00:00

[ Upstream commit d281eeaa4de2636ff0c8e6ae387bb07b50e5fcbb ]

For ADV7533 and ADV7535 low refresh rate is selected using
bits [3:2] of 0x4a main register.
So depending on ADV model write 0xfb or 0x4a register.

Fixes: 2437e7cd88e8 ("drm/bridge: adv7533: Initial support for ADV7533")
Reviewed-by: Robert Foss 
Reviewed-by: Nuno Sa 
Signed-off-by: Bogdan Togorean 
Signed-off-by: Alexandru Ardelean 
Reviewed-by: Frieder Schrempf 
Signed-off-by: Robert Foss 
Link: https://patchwork.freedesktop.org/patch/msgid/20230719060143.63649-1-alex@shruggie.ro
Signed-off-by: Sasha Levin

treewide: Remove uninitialized_var() usage

2023-08-11T09:45:01+00:00

commit 3f649ab728cda8038259d8f14492fe400fbab911 upstream.

Using uninitialized_var() is dangerous as it papers over real bugs[1]
(or can in the future), and suppresses unrelated compiler warnings
(e.g. "unused variable"). If the compiler thinks it is uninitialized,
either simply initialize the variable or make compiler changes.

In preparation for removing[2] the[3] macro[4], remove all remaining
needless uses with the following script:

git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \
	xargs perl -pi -e \
		's/\buninitialized_var\(([^\)]+)\)/\1/g;
		 s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;'

drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid
pathological white-space.

No outstanding warnings were found building allmodconfig with GCC 9.3.0
for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64,
alpha, and m68k.

[1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
[2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
[3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
[4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/

Reviewed-by: Leon Romanovsky  # drivers/infiniband and mlx4/mlx5
Acked-by: Jason Gunthorpe  # IB
Acked-by: Kalle Valo  # wireless drivers
Reviewed-by: Chao Yu  # erofs
Signed-off-by: Kees Cook 
Signed-off-by: Greg Kroah-Hartman

drm/bridge: megachips: Fix error handling in i2c_register_driver()

2023-03-11T15:31:39+00:00

[ Upstream commit 4ecff954c370b82bce45bdca2846c5c5563e8a8a ]

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: fcfa0ddc18ed ("drm/bridge: Drivers for megachips-stdpxxxx-ge-b850v3-fw (LVDS-DP++)")
Signed-off-by: Yuan Can 
Reviewed-by: Andrzej Hajda 
Tested-by: Ian Ray 
Signed-off-by: Robert Foss 
Link: https://patchwork.freedesktop.org/patch/msgid/20221108091226.114524-1-yuancan@huawei.com
Signed-off-by: Sasha Levin

drm/bridge: megachips: Fix a null pointer dereference bug

2022-10-26T11:19:27+00:00

[ Upstream commit 1ff673333d46d2c1b053ebd0c1c7c7c79e36943e ]

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: 11632d4aa2b3 ("drm/bridge: megachips: Ensure both bridges are probed before registration")
Signed-off-by: Zheyu Ma 
Signed-off-by: Robert Foss 
Link: https://patchwork.freedesktop.org/patch/msgid/20220830073450.1897020-1-zheyuma97@gmail.com
Signed-off-by: Sasha Levin

drm: bridge: adv7511: fix CEC power down control register offset

2022-10-26T11:19:27+00:00

[ Upstream commit 1d22b6033ea113a4c3850dfa2c0770885c81aec8 ]

The ADV7511_REG_CEC_CTRL = 0xE2 register is part of the main register
map - not the CEC register map. As such, we shouldn't apply an offset to
the register address. Doing so will cause us to address a bogus register
for chips with a CEC register map offset (e.g. ADV7533).

Fixes: 3b1b975003e4 ("drm: adv7511/33: add HDMI CEC support")
Signed-off-by: Alvin Šipraga 
Reviewed-by: Robert Foss 
Signed-off-by: Robert Foss 
Link: https://patchwork.freedesktop.org/patch/msgid/20220612144854.2223873-2-alvin@pqrs.dk
Signed-off-by: Sasha Levin

Revert "drm: bridge: analogix/dp: add panel prepare/unprepare in suspend/resume time"

2022-10-05T08:36:45+00:00

[ Upstream commit cc62d98bd56d45de4531844ca23913a15136c05b ]

This reverts commit 211f276ed3d96e964d2d1106a198c7f4a4b3f4c0.

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: 211f276ed3d9 ("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 
Reviewed-by: Douglas Anderson 
Signed-off-by: Douglas Anderson 
Link: https://patchwork.freedesktop.org/patch/msgid/20220822180729.1.I8ac5abe3a4c1c6fd5c061686c6e883c22f69022c@changeid
Signed-off-by: Sasha Levin