kernel/linux.git/include/drm, branch v5.10.185

drm/bridge: Fix returned array size name for atomic_get_input_bus_fmts kdoc

2023-03-22T12:29:58+00:00

[ Upstream commit 0d3c9333d976af41d7dbc6bf4d9d2e95fbdf9c89 ] The returned array size for input formats is set through atomic_get_input_bus_fmts()'s 'num_input_fmts' argument, so use 'num_input_fmts' to represent the array size in the function's kdoc, not 'num_output_fmts'. Fixes: 91ea83306bfa ("drm/bridge: Fix the bridge kernel doc") Fixes: f32df58acc68 ("drm/bridge: Add the necessary bits to support bus format negotiation") Signed-off-by: Liu Ying Reviewed-by: Robert Foss Signed-off-by: Neil Armstrong Link: https://patchwork.freedesktop.org/patch/msgid/20230314055035.3731179-1-victor.liu@nxp.com Signed-off-by: Sasha Levin

drm/mipi-dsi: Fix byte order of 16-bit DCS set/get brightness

2023-03-11T15:39:33+00:00

[ Upstream commit c9d27c6be518b4ef2966d9564654ef99292ea1b3 ] The MIPI DCS specification demands that brightness values are sent in big endian byte order. It also states that one parameter (i.e. one byte) shall be sent/received for 8 bit wide values, and two parameters shall be used for values that are between 9 and 16 bits wide. Add new functions to properly handle 16-bit brightness in big endian, since the two 8- and 16-bit cases are distinct from each other. [richard: use separate functions instead of switch/case] [richard: split into 16-bit component] Fixes: 1a9d759331b8 ("drm/dsi: Implement DCS set/get display brightness") Signed-off-by: Daniel Mentz Link: https://android.googlesource.com/kernel/msm/+/754affd62d0ee268c686c53169b1dbb7deac8550 [richard: fix 16-bit brightness_get] Signed-off-by: Richard Acayan Tested-by: Caleb Connolly Reviewed-by: Neil Armstrong Reviewed-by: Sam Ravnborg Signed-off-by: Neil Armstrong Link: https://patchwork.freedesktop.org/patch/msgid/20230116224909.23884-2-mailingradian@gmail.com Signed-off-by: Sasha Levin

drm: fix EDID struct for old ARM OABI format

2022-06-09T08:20:59+00:00

[ Upstream commit 47f15561b69e226bfc034e94ff6dbec51a4662af ] When building the kernel for arm with the "-mabi=apcs-gnu" option, gcc will force alignment of all structures and unions to a word boundary (see also STRUCTURE_SIZE_BOUNDARY and the "-mstructure-size-boundary=XX" option if you're a gcc person), even when the members of said structures do not want or need said alignment. This completely messes up the structure alignment of 'struct edid' on those targets, because even though all the embedded structures are marked with "__attribute__((packed))", the unions that contain them are not. This was exposed by commit f1e4c916f97f ("drm/edid: add EDID block count and size helpers"), but the bug is pre-existing. That commit just made the structure layout problem cause a build failure due to the addition of the BUILD_BUG_ON(sizeof(*edid) != EDID_LENGTH); sanity check in drivers/gpu/drm/drm_edid.c:edid_block_data(). This legacy union alignment should probably not be used in the first place, but we can fix the layout by adding the packed attribute to the union entries even when each member is already packed and it shouldn't matter in a sane build environment. You can see this issue with a trivial test program: union { struct { char c[5]; }; struct { char d; unsigned e; } __attribute__((packed)); } a = { "1234" }; where building this with a normal "gcc -S" will result in the expected 5-byte size of said union: .type a, @object .size a, 5 but with an ARM compiler and the old ABI: arm-linux-gnu-gcc -mabi=apcs-gnu -mfloat-abi=soft -S t.c you get .type a, %object .size a, 8 instead, because even though each member of the union is packed, the union itself still gets aligned. This was reported by Sudip for the spear3xx_defconfig target. Link: https://lore.kernel.org/lkml/YpCUzStDnSgQLNFN@debian/ Reported-by: Sudip Mukherjee Acked-by: Arnd Bergmann Cc: Maarten Lankhorst Cc: Maxime Ripard Cc: Thomas Zimmermann Cc: David Airlie Cc: Daniel Vetter Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

drm: protect drm_master pointers in drm_lease.c

2021-09-18T11:40:19+00:00

[ Upstream commit 56f0729a510f92151682ff6c89f69724d5595d6e ] drm_file->master pointers should be protected by drm_device.master_mutex or drm_file.master_lookup_lock when being dereferenced. However, in drm_lease.c, there are multiple instances where drm_file->master is accessed and dereferenced while neither lock is held. This makes drm_lease.c vulnerable to use-after-free bugs. We address this issue in 2 ways: 1. Add a new drm_file_get_master() function that calls drm_master_get on drm_file->master while holding on to drm_file.master_lookup_lock. Since drm_master_get increments the reference count of master, this prevents master from being freed until we unreference it with drm_master_put. 2. In each case where drm_file->master is directly accessed and eventually dereferenced in drm_lease.c, we wrap the access in a call to the new drm_file_get_master function, then unreference the master pointer once we are done using it. Reported-by: Daniel Vetter Signed-off-by: Desmond Cheong Zhi Xi Reviewed-by: Emil Velikov Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20210712043508.11584-6-desmondcheongzx@gmail.com Signed-off-by: Sasha Levin

drm: serialize drm_file.master with a new spinlock

2021-09-18T11:40:19+00:00

[ Upstream commit 0b0860a3cf5eccf183760b1177a1dcdb821b0b66 ] Currently, drm_file.master pointers should be protected by drm_device.master_mutex when being dereferenced. This is because drm_file.master is not invariant for the lifetime of drm_file. If drm_file is not the creator of master, then drm_file.is_master is false, and a call to drm_setmaster_ioctl will invoke drm_new_set_master, which then allocates a new master for drm_file and puts the old master. Thus, without holding drm_device.master_mutex, the old value of drm_file.master could be freed while it is being used by another concurrent process. However, it is not always possible to lock drm_device.master_mutex to dereference drm_file.master. Through the fbdev emulation code, this might occur in a deep nest of other locks. But drm_device.master_mutex is also the outermost lock in the nesting hierarchy, so this leads to potential deadlocks. To address this, we introduce a new spin lock at the bottom of the lock hierarchy that only serializes drm_file.master. With this change, the value of drm_file.master changes only when both drm_device.master_mutex and drm_file.master_lookup_lock are held. Hence, any process holding either of those locks can ensure that the value of drm_file.master will not change concurrently. Since no lock depends on the new drm_file.master_lookup_lock, when drm_file.master is dereferenced, but drm_device.master_mutex cannot be held, we can safely protect the master pointer with drm_file.master_lookup_lock. Reported-by: Daniel Vetter Signed-off-by: Desmond Cheong Zhi Xi Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20210712043508.11584-5-desmondcheongzx@gmail.com Signed-off-by: Sasha Levin

drm: Return -ENOTTY for non-drm ioctls

2021-07-28T12:35:47+00:00

commit 3abab27c322e0f2acf981595aa8040c9164dc9fb upstream. drm: Return -ENOTTY for non-drm ioctls Return -ENOTTY from drm_ioctl() when userspace passes in a cmd number which doesn't relate to the drm subsystem. Glibc uses the TCGETS ioctl to implement isatty(), and without this change isatty() returns it incorrectly returns true for drm devices. To test run this command: $ if [ -t 0 ]; then echo is a tty; fi < /dev/dri/card0 which shows "is a tty" without this patch. This may also modify memory which the userspace application is not expecting. Signed-off-by: Charles Baylis Cc: stable@vger.kernel.org Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/YPG3IBlzaMhfPqCr@stando.fishzet.co.uk Signed-off-by: Greg Kroah-Hartman

drm/dp/mst: Export drm_dp_get_vc_payload_bw()

2021-02-10T08:29:18+00:00

commit 83404d581471775f37f85e5261ec0d09407d8bed upstream. This function will be needed by the next patch where the driver calculates the BW based on driver specific parameters, so export it. At the same time sanitize the function params, passing the more natural link rate instead of the encoding of the same rate. v2: - Fix function documentation. (Lyude) Cc: Lyude Paul Cc: Ville Syrjala Cc: Cc: dri-devel@lists.freedesktop.org Signed-off-by: Imre Deak Reviewed-by: Lyude Paul Link: https://patchwork.freedesktop.org/patch/msgid/20210125173636.1733812-1-imre.deak@intel.com (cherry picked from commit a321fc2b4e60fc1b39517d26c8104351636a6062) Signed-off-by: Jani Nikula Signed-off-by: Greg Kroah-Hartman

drm: drm_print.h: fix kernel-doc markups

2020-10-27T10:21:39+00:00

A kernel-doc markup should start with the identifier on its first line. Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/5b76c5625709aaaa3abee98faa620b9f3d27ff85.1603791716.git.mchehab+huawei@kernel.org

drm: kernel-doc: drm_dp_helper.h: fix a typo

2020-10-27T10:21:27+00:00

Right now, kernel-doc generates a warning: ./include/drm/drm_dp_helper.h:1786: warning: Function parameter or member 'hbr2_reset' not described in 'drm_dp_phy_test_params' This is due to a typo: @hb2_reset -> @hbr2_reset Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/2a615cb38e951215bb1bddc2481ad323c9cf3fc9.1603791716.git.mchehab+huawei@kernel.org

drm: drm_edid: remove a duplicated kernel-doc declaration

2020-10-27T10:20:55+00:00

It is not possible to create cross-references for duplicated symbols. While Sphinx always detected it, on Sphinx 3 it generates warnings like this: .../Documentation/gpu/drm-kms-helpers:326: ../drivers/gpu/drm/drm_edid.c:1626: WARNING: Duplicate C declaration, also defined in 'gpu/drm-kms-helpers'. Declaration is 'bool drm_edid_are_equal (const struct edid *edid1, const struct edid *edid2)'. So, get rid of the duplicated kernel-doc markup. Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/9310f4074fa9d29cd3ad60684d86d0ace8dab7ae.1603791716.git.mchehab+huawei@kernel.org