motorhead/qemu
1
0
Fork 0
mirror of https://github.com/Motorhead1991/qemu.git synced 2025-08-02 07:13:54 -06:00
Code Issues Projects Releases Packages Wiki Activity Actions

Kconfig: Add I2C_DEVICES device group

Browse source 
Currently there is no way for a board model's Kconfig stanza to
say "I have an i2c bus which the user can plug an i2c device into,
build all the free-standing i2c devices". The Kconfig mechanism
for this is the "device group". Add an I2C_DEVICES group along
the same lines as the existing PCI_DEVICES. Simple free-standing
i2c devices which a user might plausibly want to be able to
plug in on the QEMU commandline should have
   default y if I2C_DEVICES
and board models which have an i2c bus that is user-accessible
should use
   imply I2C_DEVICES
to cause those pluggable devices to be built.

In this commit we mark only a fairly conservative set of i2c devices
as belonging to the I2C_DEVICES group: the simple sensors and RTCs
(not including PMBus devices or devices which need GPIO lines to be
connected).

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Hao Wu <wuhaotsh@google.com>
Message-id: 20220208155911.3408455-2-peter.maydell@linaro.org
This commit is contained in:
Peter Maydell 2022-02-08 15:59:10 +00:00
parent 92d6528dbb
commit b5bf5a53d1
4 changed files with 18 additions and 2 deletions
Download patch file Download diff file Expand all files Collapse all files

8
docs/devel/kconfig.rst
View file

@ -192,11 +192,15 @@ declares its dependencies in different ways:
no directive and are not used in the Makefile either; they only appear
as conditions for ``default y`` directives.
QEMU currently has two device groups, ``PCI_DEVICES`` and
``TEST_DEVICES``. PCI devices usually have a ``default y if
QEMU currently has three device groups, ``PCI_DEVICES``, ``I2C_DEVICES``,
and ``TEST_DEVICES``. PCI devices usually have a ``default y if
PCI_DEVICES`` directive rather than just ``default y``. This lets
some boards (notably s390) easily support a subset of PCI devices,
for example only VFIO (passthrough) and virtio-pci devices.
``I2C_DEVICES`` is similar to ``PCI_DEVICES``. It contains i2c devices
that users might reasonably want to plug in to an i2c bus on any
board (and not ones which are very board-specific or that need
to be wired up in a way that can't be done on the command line).
``TEST_DEVICES`` instead is used for devices that are rarely used on
production virtual machines, but provide useful hooks to test QEMU
or KVM.