linux-stable.git/drivers/gpu/drm/tiny, branch v6.18.27

drm/arcpgu: fix device node leak

2026-05-07T04:11:45+00:00

commit ad3ac32a3893a2bbcad545efc005a8e4e7ecf10c upstream.

This function gets a device_node reference via
of_graph_get_remote_port_parent() and stores it in encoder_node, but never
puts that reference. Add it.

There used to be a of_node_put(encoder_node) but it has been removed by
mistake during a rework in commit 3ea66a794fdc ("drm/arc: Inline
arcpgu_drm_hdmi_init").

Fixes: 3ea66a794fdc ("drm/arc: Inline arcpgu_drm_hdmi_init")
Cc: stable@vger.kernel.org
Reviewed-by: Louis Chauvet 
Link: https://patch.msgid.link/20260402-drm-arcgpu-fix-device-node-leak-v2-1-d773cf754ae5@bootlin.com
Signed-off-by: Luca Ceresoli 
Signed-off-by: Greg Kroah-Hartman

drm/tiny: sharp-memory: fix pointer error dereference

2026-03-12T11:09:09+00:00

[ Upstream commit 46120745bb4e7e1f09959624716b4c5d6e2c2e9e ]

The function devm_drm_dev_alloc() returns a pointer error upon failure
not NULL. Change null check to pointer error check.

Detected by Smatch:
drivers/gpu/drm/tiny/sharp-memory.c:549 sharp_memory_probe() error:
'smd' dereferencing possible ERR_PTR()

Fixes: b8f9f21716fec ("drm/tiny: Add driver for Sharp Memory LCD")
Signed-off-by: Ethan Tidmore 
Reviewed-by: Thomas Zimmermann 
Signed-off-by: Thomas Zimmermann 
Link: https://patch.msgid.link/20260216040438.43702-1-ethantidmore06@gmail.com
Signed-off-by: Sasha Levin

drm/tiny: pixpaper: add explicit dependency on MMU

2025-11-06T12:47:29+00:00

The DRM_GEM_SHMEM_HELPER helper requires MMU enabled because it uses
vmf_insert_pfn() in its mmap implementation. On NOMMU configurations
(e.g. some RISC-V randconfig builds), this symbol is unavailable and
selecting DRM_GEM_SHMEM_HELPER causes a modpost undefined reference:

    ERROR: modpost: "vmf_insert_pfn" [drivers/gpu/drm/drm_shmem_helper.ko] undefined!

Normally, Kconfig prevents this helper from being selected when
CONFIG_MMU=n. However, in some randconfig builds (such as those used by
0day CI), select statements can override unmet dependencies, triggering
the issue.

Add an explicit dependency on MMU to DRM_PIXPAPER to prevent this.

Reported-by: kernel test robot 
Closes: https://lore.kernel.org/oe-kbuild-all/202510280213.0rlYA4T3-lkp@intel.com/
Fixes: 0c4932f6ddf8 ("drm/tiny: pixpaper: Fix missing dependency on DRM_GEM_SHMEM_HELPER")
Acked-by: Thomas Zimmermann 
Signed-off-by: LiangCheng Wang 
Signed-off-by: Thomas Zimmermann 
Link: https://patch.msgid.link/20251028-bar-v1-1-edfbd13fafff@gmail.com

drm/tiny: pixpaper: Fix missing dependency on DRM_GEM_SHMEM_HELPER

2025-09-23T12:07:04+00:00

The driver uses drm_gem_shmem_prime_import_no_map() and
drm_gem_shmem_dumb_create(), but the Kconfig currently selects
DRM_GEM_DMA_HELPER instead of DRM_GEM_SHMEM_HELPER. This causes
link failures when DRM_GEM_SHMEM_HELPER is not enabled.

Select DRM_GEM_SHMEM_HELPER to fix the build.

Reported-by: kernel test robot 
Closes: https://lore.kernel.org/oe-kbuild-all/202509220320.gfFZjmyg-lkp@intel.com/
Fixes: c9e70639f591 ("drm: tiny: Add support for Mayqueen Pixpaper e-ink panel")
Reviewed-by: Thomas Zimmermann 
Signed-off-by: LiangCheng Wang 
Signed-off-by: Thomas Zimmermann 
Link: https://lore.kernel.org/r/20250922-bar-v1-1-b2a1f54ace82@gmail.com

drm/pixpaper: Fix return type of pixpaper_mode_valid()

2025-09-15T10:29:37+00:00

When building with -Wincompatible-function-pointer-types-strict, a
warning designed to catch kernel control flow integrity (kCFI) issues at
build time, there is an instance in the new tiny DRM pixpaper driver:

  drivers/gpu/drm/tiny/pixpaper.c:982:16: error: incompatible function pointer types initializing 'enum drm_mode_status (*)(struct drm_crtc *, const struct drm_display_mode *)' with an expression of type 'int (struct drm_crtc *, const struct drm_display_mode *)' [-Werror,-Wincompatible-function-pointer-types-strict]
    982 |         .mode_valid = pixpaper_mode_valid,
        |                       ^~~~~~~~~~~~~~~~~~~

While 'int' and 'enum drm_mode_status' are ABI compatible, hence no
regular warning from -Wincompatible-function-pointer-types, the mismatch
will trigger a kCFI violation when pixpaper_mode_valid() is called
indirectly.

Update the return type of pixpaper_mode_valid() to be
'enum drm_mode_status' to clear up the warning and kCFI violation.

Fixes: c9e70639f591 ("drm: tiny: Add support for Mayqueen Pixpaper e-ink panel")
Signed-off-by: Nathan Chancellor 
Reviewed-by: Thomas Zimmermann 
Signed-off-by: Thomas Zimmermann 
Link: https://lore.kernel.org/r/20250908-drm-pixpaper-fix-mode_valid-return-type-v1-1-705ceaf03757@kernel.org

drm/tiny/bochs: Convert dev_err() to drm_err()

2025-09-08T12:50:35+00:00

The DRM subsystem has a set of preferred, prefixed logging functions
(drm_info, drm_warn, drm_err) which improve debuggability by including
the driver and function name in the log output.

As part of the ongoing effort to modernize logging calls,
convert a dev_err() call in the bochs hardware initialization
function to its drm_err() equivalent.

This work was suggested by the DRM TODO list.

Signed-off-by: Leander Kieweg 
Reviewed-by: Thomas Zimmermann 
Signed-off-by: Thomas Zimmermann 
Link: https://lore.kernel.org/r/20250818113530.187440-1-kieweg.leander@gmail.com

drm: tiny: Add support for Mayqueen Pixpaper e-ink panel

2025-09-05T12:53:07+00:00

Introduce a DRM driver for the Mayqueen Pixpaper e-ink display panel,
which is controlled via SPI. The driver supports a 122x250 resolution
display with XRGB8888 format.

Also, add a MAINTAINERS entry for the Pixpaper driver.

Signed-off-by: LiangCheng Wang 
Reviewed-by: Thomas Zimmermann 
Signed-off-by: Thomas Zimmermann 
Link: https://lore.kernel.org/r/20250902-drm-v5-3-d77c678c4ae3@gmail.com

drm/sharp-memory: Do not access GEM-DMA vaddr directly

2025-08-11T16:49:55+00:00

Use DRM's shadow-plane helper to map and access the GEM object's buffer
within kernel address space. Encapsulates the vmap logic in the GEM-DMA
helpers.

The sharp-memory driver currently reads the vaddr field from the GME
buffer object directly. This only works because GEM code 'automagically'
sets vaddr.

Shadow-plane helpers perform the same steps, but with correct abstraction
behind drm_gem_vmap(). The shadow-plane state provides the buffer address
in kernel address space and the format-conversion state.

v2:
- fix typo in commit description

Signed-off-by: Thomas Zimmermann 
Reviewed-by: Javier Martinez Canillas 
Link: https://lore.kernel.org/r/20250627152327.8244-1-tzimmermann@suse.de

drm/repaper: Do not access GEM-DMA vaddr directly

2025-08-11T16:49:05+00:00

Use DRM's shadow-plane helper to map and access the GEM object's buffer
within kernel address space. Encapsulates the vmap logic in the GEM-DMA
helpers.

The repaper driver currently reads the vaddr field from the GME buffer
object directly. This only works because GEM code 'automagically' sets
vaddr.

Shadow-plane helpers perform the same steps, but with correct abstraction
behind drm_gem_vmap(). The shadow-plane state provides the buffer address
in kernel address space and the format-conversion state.

v2:
- fix typo in commit description

Signed-off-by: Thomas Zimmermann 
Reviewed-by: Javier Martinez Canillas 
Link: https://lore.kernel.org/r/20250627152422.8399-1-tzimmermann@suse.de

drm/bochs: Add support for drm_panic

2025-06-23T09:30:18+00:00

Add drm_panic module for bochs drm so that panic screen can be displayed
on panic.

Signed-off-by: Ryosuke Yasuoka 
Reviewed-by: Jocelyn Falempe 
Link: https://lore.kernel.org/r/20250613132023.106946-1-ryasuoka@redhat.com
Signed-off-by: Jocelyn Falempe