linux/include
Tomi Valkeinen 08e5c36410 media: v4l: subdev: Move out subdev state lock macros outside CONFIG_MEDIA_CONTROLLER
The subdev state locking macros and macros to get the active state are
currently behind CONFIG_MEDIA_CONTROLLER. This makes sense, as there can
be no subdev state without MC.

However, we have code paths common to MC and non-MC cases which call
subdev operations that have subdev state as a parameter. In the non-MC
case the state parameter would always be NULL.

Thus it makes sense to allow, e.g.:

v4l2_subdev_call_state_active(sd, pad, get_fmt, fmt)

which for non-MC case would call the subdev passing NULL as the state.

This currently fails:
https://lore.kernel.org/oe-kbuild-all/202312061101.PLrz5NnJ-lkp@intel.com/

Fix the issue by moving the related macros to be outside
CONFIG_MEDIA_CONTROLLER. The v4l2_subdev_lock_state() and
v4l2_subdev_unlock_state() macros will crash if given NULL as the state,
but the other macros behave correctly even when there's no active state,
and they will only call the lock/unlock macros if there is a state.

An alternative fix would be to make another version of
v4l2_subdev_call_state_try() with ifdefs, which would not use any state
macros and would always pass NULL as the state. But having two version
of a macro/function is always more confusing than having just one, so I
went this way.

So, this fixes the v4l2_subdev_call_state_active() macro. But we also
have v4l2_subdev_call_state_try(). It would be possible to fix that
macro by additionally creating "no-op" variants of the state alloc and
free functions. However, v4l2_subdev_call_state_try() is only used by a
single driver (stm32-dcmi), which selects MC, and the macro is supposed
to be removed as soon as the users have been converted away from the
macro. Thus I have not touched the state alloc/free functions, and I
think it makes sense to keep alloc/free functions available only if
there's actually something that can be allocated or freed.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Link: https://lore.kernel.org/r/20231208-v4l2-state-mc-fix-v1-1-a0c8162557c6@ideasonboard.com
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
2023-12-13 16:52:34 +01:00
..
acpi ACPI: PM: Add acpi_device_fix_up_power_children() function 2023-11-20 17:31:49 +01:00
asm-generic asm-generic: qspinlock: fix queued_spin_value_unlocked() implementation 2023-11-22 09:32:49 -08:00
clocksource
crypto
drm amd-drm-fixes-6.7-2023-11-30: 2023-12-01 13:57:11 +10:00
dt-bindings linux-watchdog 6.7-rc1 tag 2023-11-09 13:54:25 -08:00
keys
kunit
kvm
linux device property: Add fwnode_name_eq() 2023-12-04 10:37:46 +01:00
math-emu
media media: v4l: subdev: Move out subdev state lock macros outside CONFIG_MEDIA_CONTROLLER 2023-12-13 16:52:34 +01:00
memory
misc
net wireless fixes: 2023-11-29 19:43:34 -08:00
pcmcia
ras
rdma
rv
scsi scsi: sd: Fix system start for ATA devices 2023-11-24 20:44:21 -05:00
soc IOMMU Updates for Linux v6.7 2023-11-09 13:37:28 -08:00
sound ALSA: cs35l41: Fix for old systems which do not support command 2023-11-20 12:37:01 +01:00
target
trace rxrpc: Fix RTT determination to use any ACK as a source 2023-11-17 02:50:33 +00:00
uapi media: v4l2-subdev: Fix indentation in v4l2-subdev.h 2023-12-04 11:21:47 +01:00
ufs
vdso
video
xen xen/events: reduce externally visible helper functions 2023-11-14 09:29:28 +01:00