History log of /linux-6.15/include/media/media-dev-allocator.h (Results 1 – 2 of 2)
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Revision tags: v6.15, v6.15-rc7, v6.15-rc6, v6.15-rc5, v6.15-rc4, v6.15-rc3, v6.15-rc2, v6.15-rc1, v6.14, v6.14-rc7, v6.14-rc6, v6.14-rc5, v6.14-rc4, v6.14-rc3, v6.14-rc2, v6.14-rc1, v6.13, v6.13-rc7, v6.13-rc6, v6.13-rc5, v6.13-rc4, v6.13-rc3, v6.13-rc2, v6.13-rc1, v6.12, v6.12-rc7, v6.12-rc6, v6.12-rc5, v6.12-rc4, v6.12-rc3, v6.12-rc2, v6.12-rc1, v6.11, v6.11-rc7, v6.11-rc6, v6.11-rc5, v6.11-rc4, v6.11-rc3, v6.11-rc2, v6.11-rc1, v6.10, v6.10-rc7, v6.10-rc6, v6.10-rc5, v6.10-rc4, v6.10-rc3, v6.10-rc2, v6.10-rc1, v6.9, v6.9-rc7, v6.9-rc6, v6.9-rc5, v6.9-rc4, v6.9-rc3, v6.9-rc2, v6.9-rc1, v6.8, v6.8-rc7, v6.8-rc6, v6.8-rc5, v6.8-rc4, v6.8-rc3, v6.8-rc2, v6.8-rc1, v6.7, v6.7-rc8, v6.7-rc7, v6.7-rc6, v6.7-rc5, v6.7-rc4, v6.7-rc3, v6.7-rc2, v6.7-rc1, v6.6, v6.6-rc7, v6.6-rc6, v6.6-rc5, v6.6-rc4, v6.6-rc3, v6.6-rc2, v6.6-rc1, v6.5, v6.5-rc7, v6.5-rc6, v6.5-rc5, v6.5-rc4, v6.5-rc3, v6.5-rc2, v6.5-rc1, v6.4, v6.4-rc7, v6.4-rc6, v6.4-rc5, v6.4-rc4, v6.4-rc3, v6.4-rc2, v6.4-rc1, v6.3, v6.3-rc7, v6.3-rc6, v6.3-rc5, v6.3-rc4, v6.3-rc3, v6.3-rc2, v6.3-rc1, v6.2, v6.2-rc8, v6.2-rc7, v6.2-rc6, v6.2-rc5, v6.2-rc4, v6.2-rc3, v6.2-rc2, v6.2-rc1, v6.1, v6.1-rc8, v6.1-rc7, v6.1-rc6, v6.1-rc5, v6.1-rc4, v6.1-rc3, v6.1-rc2, v6.1-rc1, v6.0, v6.0-rc7, v6.0-rc6, v6.0-rc5, v6.0-rc4, v6.0-rc3, v6.0-rc2, v6.0-rc1, v5.19, v5.19-rc8, v5.19-rc7, v5.19-rc6, v5.19-rc5, v5.19-rc4, v5.19-rc3, v5.19-rc2, v5.19-rc1, v5.18, v5.18-rc7, v5.18-rc6, v5.18-rc5, v5.18-rc4, v5.18-rc3, v5.18-rc2, v5.18-rc1, v5.17, v5.17-rc8, v5.17-rc7, v5.17-rc6, v5.17-rc5, v5.17-rc4, v5.17-rc3, v5.17-rc2, v5.17-rc1, v5.16, v5.16-rc8, v5.16-rc7, v5.16-rc6, v5.16-rc5, v5.16-rc4, v5.16-rc3, v5.16-rc2, v5.16-rc1, v5.15, v5.15-rc7, v5.15-rc6, v5.15-rc5, v5.15-rc4, v5.15-rc3, v5.15-rc2, v5.15-rc1, v5.14, v5.14-rc7, v5.14-rc6, v5.14-rc5, v5.14-rc4, v5.14-rc3, v5.14-rc2, v5.14-rc1, v5.13, v5.13-rc7
# 50e7a31d 16-Jun-2021 Shuah Khan <[email protected]>

media: Fix Media Controller API config checks

Smatch static checker warns that "mdev" can be null:

sound/usb/media.c:287 snd_media_device_create()
warn: 'mdev' can also be NULL

If CONFIG_MEDIA

media: Fix Media Controller API config checks

Smatch static checker warns that "mdev" can be null:

sound/usb/media.c:287 snd_media_device_create()
warn: 'mdev' can also be NULL

If CONFIG_MEDIA_CONTROLLER is disabled, this file should not be included
in the build.

The below conditions in the sound/usb/Makefile are in place to ensure that
media.c isn't included in the build.

sound/usb/Makefile:
snd-usb-audio-$(CONFIG_SND_USB_AUDIO_USE_MEDIA_CONTROLLER) += media.o

select SND_USB_AUDIO_USE_MEDIA_CONTROLLER if MEDIA_CONTROLLER &&
(MEDIA_SUPPORT=y || MEDIA_SUPPORT=SND_USB_AUDIO)

The following config check in include/media/media-dev-allocator.h is
in place to enable the API only when CONFIG_MEDIA_CONTROLLER and
CONFIG_USB are enabled.

#if defined(CONFIG_MEDIA_CONTROLLER) && defined(CONFIG_USB)

This check doesn't work as intended when CONFIG_USB=m. When CONFIG_USB=m,
CONFIG_USB_MODULE is defined and CONFIG_USB is not. The above config check
doesn't catch that CONFIG_USB is defined as a module and disables the API.
This results in sound/usb enabling Media Controller specific ALSA driver
code, while Media disables the Media Controller API.

Fix the problem requires two changes:

1. Change the check to use IS_ENABLED to detect when CONFIG_USB is enabled
as a module or static. Since CONFIG_MEDIA_CONTROLLER is a bool, leave
the check unchanged to be consistent with drivers/media/Makefile.

2. Change the drivers/media/mc/Makefile to include mc-dev-allocator.o
in mc-objs when CONFIG_USB is enabled.

Link: https://lore.kernel.org/alsa-devel/YLeAvT+R22FQ%2FEyw@mwanda/

Reported-by: Dan Carpenter <[email protected]>
Signed-off-by: Shuah Khan <[email protected]>
Signed-off-by: Hans Verkuil <[email protected]>
Signed-off-by: Mauro Carvalho Chehab <[email protected]>

show more ...


Revision tags: v5.13-rc6, v5.13-rc5, v5.13-rc4, v5.13-rc3, v5.13-rc2, v5.13-rc1, v5.12, v5.12-rc8, v5.12-rc7, v5.12-rc6, v5.12-rc5, v5.12-rc4, v5.12-rc3, v5.12-rc2, v5.12-rc1, v5.12-rc1-dontuse, v5.11, v5.11-rc7, v5.11-rc6, v5.11-rc5, v5.11-rc4, v5.11-rc3, v5.11-rc2, v5.11-rc1, v5.10, v5.10-rc7, v5.10-rc6, v5.10-rc5, v5.10-rc4, v5.10-rc3, v5.10-rc2, v5.10-rc1, v5.9, v5.9-rc8, v5.9-rc7, v5.9-rc6, v5.9-rc5, v5.9-rc4, v5.9-rc3, v5.9-rc2, v5.9-rc1, v5.8, v5.8-rc7, v5.8-rc6, v5.8-rc5, v5.8-rc4, v5.8-rc3, v5.8-rc2, v5.8-rc1, v5.7, v5.7-rc7, v5.7-rc6, v5.7-rc5, v5.7-rc4, v5.7-rc3, v5.7-rc2, v5.7-rc1, v5.6, v5.6-rc7, v5.6-rc6, v5.6-rc5, v5.6-rc4, v5.6-rc3, v5.6-rc2, v5.6-rc1, v5.5, v5.5-rc7, v5.5-rc6, v5.5-rc5, v5.5-rc4, v5.5-rc3, v5.5-rc2, v5.5-rc1, v5.4, v5.4-rc8, v5.4-rc7, v5.4-rc6, v5.4-rc5, v5.4-rc4, v5.4-rc3, v5.4-rc2, v5.4-rc1, v5.3, v5.3-rc8, v5.3-rc7, v5.3-rc6, v5.3-rc5, v5.3-rc4, v5.3-rc3, v5.3-rc2, v5.3-rc1, v5.2, v5.2-rc7, v5.2-rc6, v5.2-rc5, v5.2-rc4, v5.2-rc3, v5.2-rc2, v5.2-rc1, v5.1, v5.1-rc7, v5.1-rc6, v5.1-rc5, v5.1-rc4
# 6e1d824e 02-Apr-2019 Shuah Khan <[email protected]>

media: Media Device Allocator API

Media Device Allocator API to allows multiple drivers share a media device.
This API solves a very common use-case for media devices where one physical
device (an U

media: Media Device Allocator API

Media Device Allocator API to allows multiple drivers share a media device.
This API solves a very common use-case for media devices where one physical
device (an USB stick) provides both audio and video. When such media device
exposes a standard USB Audio class, a proprietary Video class, two or more
independent drivers will share a single physical USB bridge. In such cases,
it is necessary to coordinate access to the shared resource.

Using this API, drivers can allocate a media device with the shared struct
device as the key. Once the media device is allocated by a driver, other
drivers can get a reference to it. The media device is released when all
the references are released.

Signed-off-by: Shuah Khan <[email protected]>
Signed-off-by: Hans Verkuil <[email protected]>
Signed-off-by: Mauro Carvalho Chehab <[email protected]>

show more ...