i3c: Add comment for -EAGAIN in i3c_device_do_priv_xfers()

In accordance with I3C spec ver 1.1.1 09-Jun-2021, section: 5.1.2.2.3, if
a target requests hot join (HJ), In-Band Interrupt (IBI), or cont

i3c: Add comment for -EAGAIN in i3c_device_do_priv_xfers()

In accordance with I3C spec ver 1.1.1 09-Jun-2021, section: 5.1.2.2.3, if
a target requests hot join (HJ), In-Band Interrupt (IBI), or controller
role request (CRR) during the emission of an I3C address in
i3c_device_do_priv_xfers(), the target may win bus arbitration. In such
cases, it is imperative to notify the I3C client driver and retry
i3c_device_do_priv_xfers() after some delay.

Signed-off-by: Frank Li <[email protected]>
Reviewed-by: Miquel Raynal <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Belloni <[email protected]>

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driver core: make struct device_type.uevent() take a const *

The uevent() callback in struct device_type should not be modifying the
device that is passed into it, so mark it as a const * and propag

driver core: make struct device_type.uevent() take a const *

The uevent() callback in struct device_type should not be modifying the
device that is passed into it, so mark it as a const * and propagate the
function signature changes out into all relevant subsystems that use
this callback.

Cc: Alan Stern <[email protected]>
Cc: Andreas Noever <[email protected]>
Cc: Andy Shevchenko <[email protected]>
Cc: Bard Liao <[email protected]>
Cc: Chaitanya Kulkarni <[email protected]>
Cc: Dan Williams <[email protected]>
Cc: Dmitry Torokhov <[email protected]>
Cc: Frank Rowand <[email protected]>
Cc: Ira Weiny <[email protected]>
Cc: Jason Gunthorpe <[email protected]>
Cc: Jens Axboe <[email protected]>
Cc: Jilin Yuan <[email protected]>
Cc: Jiri Slaby <[email protected]>
Cc: Len Brown <[email protected]>
Cc: Mark Gross <[email protected]>
Cc: "Martin K. Petersen" <[email protected]>
Cc: "Matthew Wilcox (Oracle)" <[email protected]>
Cc: Maximilian Luz <[email protected]>
Cc: Michael Jamet <[email protected]>
Cc: Ming Lei <[email protected]>
Cc: Pierre-Louis Bossart <[email protected]>
Cc: Rob Herring <[email protected]>
Cc: Sakari Ailus <[email protected]>
Cc: Sanyog Kale <[email protected]>
Cc: Sean Young <[email protected]>
Cc: Stefan Richter <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Won Chung <[email protected]>
Cc: Yehezkel Bernat <[email protected]>
Acked-by: Rafael J. Wysocki <[email protected]>
Acked-by: Mika Westerberg <[email protected]> # for Thunderbolt
Acked-by: Mauro Carvalho Chehab <[email protected]>
Acked-by: Alexandre Belloni <[email protected]>
Acked-by: Heikki Krogerus <[email protected]>
Acked-by: Wolfram Sang <[email protected]>
Acked-by: Vinod Koul <[email protected]>
Acked-by: Hans de Goede <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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i3c: move dev_to_i3cdev() to use container_of_const()

The driver core is changing to pass some pointers as const, so move
dev_to_i3cdev() to use container_of_const() to handle this change.
dev_to_i3

i3c: move dev_to_i3cdev() to use container_of_const()

The driver core is changing to pass some pointers as const, so move
dev_to_i3cdev() to use container_of_const() to handle this change.
dev_to_i3cdev() now properly keeps the const-ness of the pointer passed
into it, while as before it could be lost.

Acked-by: Alexandre Belloni <[email protected]>
Acked-by: Hans de Goede <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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i3c: export SETDASA method

Because not all I3C drivers have the hot-join feature ready, and
especially not all I3C devices support hot-join feature, exporting
SETDASA method could be useful. With th

i3c: export SETDASA method

Because not all I3C drivers have the hot-join feature ready, and
especially not all I3C devices support hot-join feature, exporting
SETDASA method could be useful. With this function, the I3C controller
could perform a DAA to I3C devices when users decide to turn these I3C
devices off and on again during run-time.

Tested: This change has been tested with turnning off an I3C device and
turning on it again during run-time. The device driver calls SETDASA
method to perform DAA to the device. And communication between I3C
controller and device is set up again correctly.

Signed-off-by: Jack Chen <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Belloni <[email protected]>

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i3c: Handle drivers without probe or remove callback

A registered driver without a probe callback doesn't make sense, so
refuse to register such a driver. (Otherwise i3c_device_probe() yields a
NULL

i3c: Handle drivers without probe or remove callback

A registered driver without a probe callback doesn't make sense, so
refuse to register such a driver. (Otherwise i3c_device_probe() yields a
NULL pointer exception.)

A driver without remove is possible, e.g. when all resources are freed
using devm callbacks. So guard the call to driver->remove by a check
for being non-NULL.

Note that the only in-tree i3c driver
(drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i3c.c) doesn't have a remove
callback.

Signed-off-by: Uwe Kleine-König <[email protected]>
Signed-off-by: Alexandre Belloni <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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i3c: Simplify i3c_device_match_id()

Simply match against ->match_flags instead of trying to be smart and
fix drivers inconsistent ID tables.

Signed-off-by: Boris Brezillon <boris.brezillon@collabor

i3c: Simplify i3c_device_match_id()

Simply match against ->match_flags instead of trying to be smart and
fix drivers inconsistent ID tables.

Signed-off-by: Boris Brezillon <[email protected]>
Signed-off-by: Vitor Soares <[email protected]>
Link: https://lore.kernel.org/linux-i3c/8c5d6523e1c161783db834a3447954f7fd6267e6.1582796652.git.vitor.soares@synopsys.com

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i3c: move i3c_device_match_id to device.c and export it

Some I3C device drivers need to know which entry matches the
i3c_device object passed to the probe function

Let's move i3c_device_match_id()

i3c: move i3c_device_match_id to device.c and export it

Some I3C device drivers need to know which entry matches the
i3c_device object passed to the probe function

Let's move i3c_device_match_id() to device.c and export it so it can be
used by drivers.

Signed-off-by: Vitor Soares <[email protected]>
Signed-off-by: Boris Brezillon <[email protected]>

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i3c: Add core I3C infrastructure

Add core infrastructure to support I3C in Linux and document it.

This infrastructure adds basic I3C support. Advanced features will be
added afterwards.

There are

i3c: Add core I3C infrastructure

Add core infrastructure to support I3C in Linux and document it.

This infrastructure adds basic I3C support. Advanced features will be
added afterwards.

There are a few design choices that are worth mentioning because they
impact the way I3C device drivers can interact with their devices:

- all functions used to send I3C/I2C frames must be called in
non-atomic context. Mainly done this way to ease implementation, but
this is not set in stone, and if anyone needs async support, new
functions can be added later on.
- the bus element is a separate object, but it's tightly coupled with
the master object. We thus have a 1:1 relationship between i3c_bus
and i3c_master_controller objects, and if 2 master controllers are
connected to the same bus and both exposed to the same Linux instance
they will appear as two distinct busses, and devices on this bus will
be exposed twice.
- I2C backward compatibility has been designed to be transparent to I2C
drivers and the I2C subsystem. The I3C master just registers an I2C
adapter which creates a new I2C bus. I'd say that, from a
representation PoV it's not ideal because what should appear as a
single I3C bus exposing I3C and I2C devices here appears as 2
different buses connected to each other through the parenting (the
I3C master is the parent of the I2C and I3C busses).
On the other hand, I don't see a better solution if we want something
that is not invasive.

Missing features:
- I3C HDR modes are not supported
- no support for multi-master and the associated concepts (mastership
handover, support for secondary masters, ...)
- I2C devices can only be described using DT because this is the only
use case I have. However, the framework can easily be extended with
ACPI and board info support
- I3C slave framework. This has been completely omitted, but shouldn't
have a huge impact on the I3C framework because I3C slaves don't see
the whole bus, it's only about handling master requests and generating
IBIs. Some of the struct, constant and enum definitions could be
shared, but most of the I3C slave framework logic will be different

Signed-off-by: Boris Brezillon <[email protected]>
Reviewed-by: Arnd Bergmann <[email protected]>
Acked-by: Greg Kroah-Hartman <[email protected]>

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