kernel_optimize_test/drivers/media/Kconfig
Mauro Carvalho Chehab 347f7a3763 [media] subdev autoselect only works if I2C and I2C_MUX is selected
As reported by the kbuild test robot <fengguang.wu@intel.com>:

> warning: (VIDEO_EM28XX_DVB) selects DVB_M88DS3103 which has unmet direct dependencies (MEDIA_SUPPORT && DVB_CORE && I2C && I2C_MUX)
>    drivers/built-in.o: In function `m88ds3103_release':
> >> m88ds3103.c:(.text+0x1ab1af): undefined reference to `i2c_del_mux_adapter'
>    drivers/built-in.o: In function `m88ds3103_attach':
> >> (.text+0x1ab342): undefined reference to `i2c_add_mux_adapter'

There are 3 possible ways to fix it:

1) make em28xx dependent on I2C_MUX.

That sounds wrong, as the em28xx bridge doesn't have i2c muxes on it,
and just one frontend has.

Well, subdevs could eventually be converted to, instead of using dvb
i2c gate control, to use i2c mux support.

That makes sense, but it takes time and lots of effort. Not sure if
this will happen anytime soon.

2) MEDIA_SUBDRV_AUTOSELECT can be dependent of I2C and I2C_MUX.

That means that users will need to manually enable I2C_MUX on some
distributions. Not sure about others, but, on Fedora, this option is
disabled.

So, it can end by generating a number of complains from users
that their devices suddenly stopped working after a Kernel upgrade,
at least until all distros that ship Kernels with I2C_MUX enabled.

3) if MEDIA_SUBDRV_AUTOSELECT is selected, it will select I2C and I2C_MUX.

Of course, MEDIA_SUBDRV_AUTOSELECT will need to inherit all dependencies
that I2C and I2C_MUX have (only HAS_IOMEM).

The disadvantage is that, if new dependencies are added on I2C, they'll
also need to be added here.

As the hole idea of autoselect is to let the user not bother about whatever
frontend/tuner is used by a driver, IMHO, (3) is the better solution.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
2013-12-21 06:03:06 -02:00

206 lines
5.5 KiB
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#
# Multimedia device configuration
#
menuconfig MEDIA_SUPPORT
tristate "Multimedia support"
depends on HAS_IOMEM
help
If you want to use Webcams, Video grabber devices and/or TV devices
enable this option and other options below.
Additional info and docs are available on the web at
<http://linuxtv.org>
if MEDIA_SUPPORT
comment "Multimedia core support"
#
# Multimedia support - automatically enable V4L2 and DVB core
#
config MEDIA_CAMERA_SUPPORT
bool "Cameras/video grabbers support"
---help---
Enable support for webcams and video grabbers.
Say Y when you have a webcam or a video capture grabber board.
config MEDIA_ANALOG_TV_SUPPORT
bool "Analog TV support"
---help---
Enable analog TV support.
Say Y when you have a TV board with analog support or with a
hybrid analog/digital TV chipset.
Note: There are several DVB cards that are based on chips that
support both analog and digital TV. Disabling this option
will disable support for them.
config MEDIA_DIGITAL_TV_SUPPORT
bool "Digital TV support"
---help---
Enable digital TV support.
Say Y when you have a board with digital support or a board with
hybrid digital TV and analog TV.
config MEDIA_RADIO_SUPPORT
bool "AM/FM radio receivers/transmitters support"
---help---
Enable AM/FM radio support.
Additional info and docs are available on the web at
<http://linuxtv.org>
Say Y when you have a board with radio support.
Note: There are several TV cards that are based on chips that
support radio reception. Disabling this option will
disable support for them.
config MEDIA_RC_SUPPORT
bool "Remote Controller support"
depends on INPUT
---help---
Enable support for Remote Controllers on Linux. This is
needed in order to support several video capture adapters,
standalone IR receivers/transmitters, and RF receivers.
Enable this option if you have a video capture board even
if you don't need IR, as otherwise, you may not be able to
compile the driver for your adapter.
Say Y when you have a TV or an IR device.
#
# Media controller
# Selectable only for webcam/grabbers, as other drivers don't use it
#
config MEDIA_CONTROLLER
bool "Media Controller API"
depends on MEDIA_CAMERA_SUPPORT
---help---
Enable the media controller API used to query media devices internal
topology and configure it dynamically.
This API is mostly used by camera interfaces in embedded platforms.
#
# Video4Linux support
# Only enables if one of the V4L2 types (ATV, webcam, radio) is selected
#
config VIDEO_DEV
tristate
depends on MEDIA_SUPPORT
depends on MEDIA_CAMERA_SUPPORT || MEDIA_ANALOG_TV_SUPPORT || MEDIA_RADIO_SUPPORT
default y
config VIDEO_V4L2_SUBDEV_API
bool "V4L2 sub-device userspace API"
depends on VIDEO_DEV && MEDIA_CONTROLLER
---help---
Enables the V4L2 sub-device pad-level userspace API used to configure
video format, size and frame rate between hardware blocks.
This API is mostly used by camera interfaces in embedded platforms.
source "drivers/media/v4l2-core/Kconfig"
#
# DVB Core
# Only enables if one of DTV is selected
#
config DVB_CORE
tristate
depends on MEDIA_SUPPORT
depends on MEDIA_DIGITAL_TV_SUPPORT
default y
select CRC32
config DVB_NET
bool "DVB Network Support"
default (NET && INET)
depends on NET && INET && DVB_CORE
help
This option enables DVB Network Support which is a part of the DVB
standard. It is used, for example, by automatic firmware updates used
on Set-Top-Boxes. It can also be used to access the Internet via the
DVB card, if the network provider supports it.
You may want to disable the network support on embedded devices. If
unsure say Y.
# This Kconfig option is used by both PCI and USB drivers
config TTPCI_EEPROM
tristate
depends on I2C
default n
source "drivers/media/dvb-core/Kconfig"
comment "Media drivers"
source "drivers/media/rc/Kconfig"
#
# V4L platform/mem2mem drivers
#
source "drivers/media/usb/Kconfig"
source "drivers/media/pci/Kconfig"
source "drivers/media/platform/Kconfig"
source "drivers/media/mmc/Kconfig"
source "drivers/media/parport/Kconfig"
source "drivers/media/radio/Kconfig"
comment "Supported FireWire (IEEE 1394) Adapters"
depends on DVB_CORE && FIREWIRE
source "drivers/media/firewire/Kconfig"
# Common driver options
source "drivers/media/common/Kconfig"
comment "Media ancillary drivers (tuners, sensors, i2c, frontends)"
#
# Ancillary drivers (tuners, i2c, frontends)
#
config MEDIA_SUBDRV_AUTOSELECT
bool "Autoselect ancillary drivers (tuners, sensors, i2c, frontends)"
depends on MEDIA_ANALOG_TV_SUPPORT || MEDIA_DIGITAL_TV_SUPPORT || MEDIA_CAMERA_SUPPORT
depends on HAS_IOMEM
select I2C
select I2C_MUX
default y
help
By default, a media driver auto-selects all possible ancillary
devices such as tuners, sensors, video encoders/decoders and
frontends, that are used by any of the supported devices.
This is generally the right thing to do, except when there
are strict constraints with regards to the kernel size,
like on embedded systems.
Use this option with care, as deselecting ancillary drivers which
are, in fact, necessary will result in the lack of the needed
functionality for your device (it may not tune or may not have
the needed demodulators).
If unsure say Y.
config MEDIA_ATTACH
bool
depends on MEDIA_ANALOG_TV_SUPPORT || MEDIA_DIGITAL_TV_SUPPORT || MEDIA_RADIO_SUPPORT
depends on MODULES
default MODULES
source "drivers/media/i2c/Kconfig"
source "drivers/media/tuners/Kconfig"
source "drivers/media/dvb-frontends/Kconfig"
endif # MEDIA_SUPPORT