driver core: have match() callback in struct bus_type take a const *

In the match() callback, the struct device_driver * should not be
changed, so change the function callback to be a const *. This

driver core: have match() callback in struct bus_type take a const *

In the match() callback, the struct device_driver * should not be
changed, so change the function callback to be a const *. This is one
step of many towards making the driver core safe to have struct
device_driver in read-only memory.

Because the match() callback is in all busses, all busses are modified
to handle this properly. This does entail switching some container_of()
calls to container_of_const() to properly handle the constant *.

For some busses, like PCI and USB and HV, the const * is cast away in
the match callback as those busses do want to modify those structures at
this point in time (they have a local lock in the driver structure.)
That will have to be changed in the future if they wish to have their
struct device * in read-only-memory.

Cc: Rafael J. Wysocki <[email protected]>
Reviewed-by: Alex Elder <[email protected]>
Acked-by: Sumit Garg <[email protected]>
Link: https://lore.kernel.org/r/2024070136-wrongdoer-busily-01e8@gregkh
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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slimbus: core: make slimbus_bus const

Since commit d492cc2573a0 ("driver core: device.h: make struct
bus_type a const *"), the driver core can properly handle constant
struct bus_type, move the slim

slimbus: core: make slimbus_bus const

Since commit d492cc2573a0 ("driver core: device.h: make struct
bus_type a const *"), the driver core can properly handle constant
struct bus_type, move the slimbus_bus variable to be a constant
structure as well, placing it into read-only memory which can not be
modified at runtime.

Cc: Greg Kroah-Hartman <[email protected]>
Suggested-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: "Ricardo B. Marliere" <[email protected]>
Reviewed-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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slimbus: stream: add stream support

This patch adds support to SLIMbus stream apis for slimbus device.
SLIMbus streaming involves adding support to Data Channel Management and
channel Reconfiguratio

slimbus: stream: add stream support

This patch adds support to SLIMbus stream apis for slimbus device.
SLIMbus streaming involves adding support to Data Channel Management and
channel Reconfiguration Messages to slim core plus few stream apis.
>From slim device side the apis are very simple mostly inline with other
stream apis.

Currently it only supports Isochronous and Push/Pull transport protocols,
which are sufficient for audio use cases.

Signed-off-by: Srinivas Kandagatla <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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slimbus: core: rearrange slim_eaddr structure

Rearrange struct slim_eaddr so that the structure is packed correctly
to be able to send in SLIMBus messages.

Signed-off-by: Srinivas Kandagatla <srini

slimbus: core: rearrange slim_eaddr structure

Rearrange struct slim_eaddr so that the structure is packed correctly
to be able to send in SLIMBus messages.

Signed-off-by: Srinivas Kandagatla <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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slimbus: core: add of_slim_device_get() helper

On SLIMBus controllers like Qcom NGD(non ported device), controller
can request logical address once the remote side is powered, having a
helper functi

slimbus: core: add of_slim_device_get() helper

On SLIMBus controllers like Qcom NGD(non ported device), controller
can request logical address once the remote side is powered, having a
helper function like this to explicitly enumerate the bus is helpful.
Also codec drivers which are taking to interface device would need
such a helper too.

Signed-off-by: Srinivas Kandagatla <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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slimbus: Add messaging APIs to slimbus framework

SLIMbus devices use value-element, and information elements to
control device parameters (e.g. value element is used to represent
gain for codec, inf

slimbus: Add messaging APIs to slimbus framework

SLIMbus devices use value-element, and information elements to
control device parameters (e.g. value element is used to represent
gain for codec, information element is used to represent interrupt
status for codec when codec interrupt fires).
Messaging APIs are used to set/get these value and information
elements. SLIMbus specification uses 8-bit "transaction IDs" for
messages where a read-value is anticipated. Framework uses a table
of pointers to store those TIDs and responds back to the caller in
O(1).
Caller can do synchronous and asynchronous reads/writes.

Signed-off-by: Srinivas Kandagatla <[email protected]>
Reviwed-by: Mark Brown <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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slimbus: core: Add slim controllers support

This patch adds support to slim controllers in the slim core,
including some utility functions invoked by the controller and
slim device drivers.

Signed-

slimbus: core: Add slim controllers support

This patch adds support to slim controllers in the slim core,
including some utility functions invoked by the controller and
slim device drivers.

Signed-off-by: Srinivas Kandagatla <[email protected]>
Reviwed-by: Mark Brown <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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slimbus: Add SLIMbus bus type

SLIMbus (Serial Low Power Interchip Media Bus) is a specification
developed by MIPI (Mobile Industry Processor Interface) alliance.
SLIMbus is a 2-wire implementation,

slimbus: Add SLIMbus bus type

SLIMbus (Serial Low Power Interchip Media Bus) is a specification
developed by MIPI (Mobile Industry Processor Interface) alliance.
SLIMbus is a 2-wire implementation, which is used to communicate with
peripheral components like audio-codec.
SLIMbus uses Time-Division-Multiplexing to accommodate multiple data
channels, and control channel. Control channel has messages to do
device-enumeration, messages to send/receive control-data to/from
SLIMbus devices, messages for port/channel management, and messages to
do bandwidth allocation.
The framework supports multiple instances of the bus (1 controller per
bus), and multiple slave devices per controller.

This patch adds support to basic silmbus core which includes support to
SLIMbus type, slimbus device registeration and some basic data structures.

Signed-off-by: Sagar Dharia <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
Reviwed-by: Mark Brown <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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