core: add of based component probing
Some devices are designed and manufactured with some components having
multiple drop-in replacement options. These components are often
connected to the mainboard via ribbon cables, having the same signals
and pin assignments across all options. These may include the display
panel and touchscreen on laptops and tablets, and the trackpad on
laptops. Sometimes which component option is used in a particular device
can be detected by some firmware provided identifier, other times that
information is not available, and the kernel has to try to probe each
device.
Instead of a delicate dance between drivers and device tree quirks, this
change introduces a simple I2C component probe function. For a given
class of devices on the same I2C bus, it will go through all of them,
doing a simple I2C read transfer and see which one of them responds. It
will then enable the device that responds.
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Merge tag 'i2c-for-6.13-rc1-part3' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c component probing support from Wolfram Sang:
"Add OF component probing.
Some devices are designed and manufactured with some components having
multiple drop-in replacement options. These components are often
connected to the mainboard via ribbon cables, having the same signals
and pin assignments across all options. These may include the display
panel and touchscreen on laptops and tablets, and the trackpad on
laptops. Sometimes which component option is used in a particular
device can be detected by some firmware provided identifier, other
times that information is not available, and the kernel has to try to
probe each device.
Instead of a delicate dance between drivers and device tree quirks,
this change introduces a simple I2C component probe function. For a
given class of devices on the same I2C bus, it will go through all of
them, doing a simple I2C read transfer and see which one of them
responds. It will then enable the device that responds"
* tag 'i2c-for-6.13-rc1-part3' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
MAINTAINERS: fix typo in I2C OF COMPONENT PROBER
of: base: Document prefix argument for of_get_next_child_with_prefix()
i2c: Fix whitespace style issue
arm64: dts: mediatek: mt8173-elm-hana: Mark touchscreens and trackpads as fail
platform/chrome: Introduce device tree hardware prober
i2c: of-prober: Add GPIO support to simple helpers
i2c: of-prober: Add simple helpers for regulator support
i2c: Introduce OF component probe function
of: base: Add for_each_child_of_node_with_prefix()
of: dynamic: Add of_changeset_update_prop_string
a14bf463e7