If an I2C adapter doesn't match the provided device tree node, also try
matching the parent's device tree node. This allows finding an adapter
based on the device node of the parent device that was used to register
it.
This fixes a regression on Tegra124-based Chromebooks (Nyan) where the
eDP controller registers an I2C adapter that is used to read to EDID.
After commit 993a815dcb ("dt-bindings: panel: Add missing .txt
suffix") this stopped working because the I2C adapter could no longer
be found. The approach in this patch fixes the regression without
introducing the issues that the above commit solved.
Fixes: 17ab7806de ("drm: don't link DP aux i2c adapter to the hardware device node")
Signed-off-by: Thierry Reding <treding@nvidia.com>
Tested-by: Tristan Bastian <tristan-c.bastian@gmx.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
I3C busses have to know about all I2C devices connected on the I3C bus
to properly initialize the I3C master, and I2C frames can't be sent on
the bus until this initialization is done.
We can't let the I2C core parse the DT and instantiate I2C devices as
part of its i2c_add_adapter() procedure because, when done this way,
I2C devices are directly registered to the device-model and might be
attached to drivers which could in turn start sending frames on the bus,
which won't work since, as said above, the bus is not yet initialized.
Export of_i2c_register_device() in order to let the I3C core parse the
I2C device nodes by itself and initialize the bus.
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Currently, of_i2c_register_devices() is responsible for retaining
info->of_node, but we're about to expose a function to parse I2C board
info without registering the I2C device.
We could possibly let this function retain ->of_node, but this approach
is prone to reference leak since people will have to remember to call
of_node_put() if something goes wrong between the OF node parsing and
the registration step.
Let's just retain the ->of_node in i2c_new_register() instead.
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The only user of i2c_board_info->archdata is the OF parsing code and it
just pass a zero-initialized object which has the same effect as leaving
->archdata to NULL since the client object is allocated with kzalloc().
Get rid of this useless field.
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
of_get_property() is a bit cumbersome to use. Replace it with the newer
of_property_read_u32() for more readable code.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
'result' is mostly used in the kernel as int for functions returning
errno on failure. Here it is a pointer to the client struct, so let's
call it this way (as the parent function does, too).
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
When debugging a ref counting problem, I overlooked this snipplet a few
times. Might be taste, but I think the new location is visually easier
recognizable.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Now that we have a custom printf format specifier, convert users of
full_name to use %pOF instead. This is preparation to remove storing
of the full path string for each node.
Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Thierry Reding
Boris Brezillon
Wolfram Sang
Rob Herring