staging: vc04_services: vchiq_dev: Use %p to log pointer address

Solves the following Smatch warnings:
vchiq_release() warn: argument 7 to %lx specifier is cast from pointer

%p will print the hashed pointer to dynamic debug.
In order to print the unmodified pointer address, one can use the
`no_hash_pointers` via kernel parameters.

Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
Link: https://lore.kernel.org/r/20231207083837.153843-3-umang.jain@ideasonboard.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vc04_services: Drop vchiq_log_debug() in favour of dev_dbg

Drop vchiq_log_debug() macro which wraps dev_dbg(). Introduce the usage
of dev_dbg() directly.

Meanwhile at it, drop the usage of __func__ from the logs.
Dynamic debug supports this via the 'f' decorator flag.

Remove the entry from TODO regarding custom logging. VC04 is now
aligned according to the standard kernel logging mechanisms.

Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
Link: https://lore.kernel.org/r/20231205084157.73819-5-umang.jain@ideasonboard.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vc04_services: Drop vchiq_log_trace() in favour of dev_dbg

Drop vchiq_log_trace() macro which wraps dev_dbg(). Introduce the usage
of dev_dbg() directly.

Meanwhile at it, drop the usage of __func__ from the logs.
Dynamic debug supports this via the 'f' decorator flag.

Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
Link: https://lore.kernel.org/r/20231205084157.73819-4-umang.jain@ideasonboard.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vc04_services: Drop vchiq_log_error() in favour of dev_err

Drop vchiq_log_error() macro which wraps dev_dbg(). Introduce the usage
of dev_err() directly.

Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
Link: https://lore.kernel.org/r/20231205084157.73819-2-umang.jain@ideasonboard.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vchiq_arm: move state dump to debugfs

Besides the IOCTL interface the VCHIQ character device also provides
a state dump of the whole VCHIQ driver via read. Moving the state dump
function to debugfs has a lot advantages:

- following changes on state dump doesn't break userspace ABI
- debug doesn't depend on VCHIQ_CDEV
- dump code simplifies a lot and reduce the chance of buffer overflows

Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
Tested-by: "Ricardo B. Marliere" <ricardo@marliere.net>
Link: https://lore.kernel.org/r/20231029124837.119832-4-wahrenst@gmx.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vc04_services: Use %p4cc format modifier to print FourCC codes

Drop VCHIQ_FOURCC_AS_4CHARS macro in favour of %p4cc format
modifier to print FourCC codes in the logs.

vchiq_use_internal() and vchiq_release_internal() uses entity
character-array to store a transient string that contains
a FourCC code. Increase the length of entity array(to 64 bytes)
since %p4cc requires more bytes to hold the output characters.

Suggested-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
Link: https://lore.kernel.org/r/20231025060717.71895-2-umang.jain@ideasonboard.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vc04: Convert vchiq_log_trace() to use dynamic debug

Move vchiq_log_trace() custom logging wrapper based on printk
to use dynamic debug. The log category is dictated by enum
vchiq_log_category which will become the part of the trace
string format that will be logged to dynamic debug (for grep).

All the vchiq_log_trace() calls are adjusted to use the
modified wrapper.

Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
Link: https://lore.kernel.org/r/20231024114428.443528-7-umang.jain@ideasonboard.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vc04: Convert(and rename) vchiq_log_info() to use dynamic debug

Convert(and rename) vchiq_log_info() custom logging wrapping based on
printk to use dynamic debug. The wrapper is now renamed to
vchiq_log_debug() since most of the usage is around printing debug
information. The log category is dictated by enum vchiq_log_category
which will become the part of the debug string format that will be
logged to dynamic debug (for grep).

All the vchiq_log_info() calls are adjusted to use the
modified wrapper vchiq_log_debug().

The existing custom logging for vchiq_log_info() also tries
to log trace messages using SRVTRACE_LEVEL. This is simply
moved to use the vchiq_log_debug() directly.

Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
Link: https://lore.kernel.org/r/20231024114428.443528-6-umang.jain@ideasonboard.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vc04: Convert vchiq_log_error() to use dynamic debug

Move vchiq_log_error() custom logging wrapper based on printk,
to use dynamic debug. To categorise, enum vchiq_log_category
has been introduced, which will become the part of the error
string format that will be logged to dynamic debug (for grep).

All the vchiq_log_error() calls are adjusted to use the
dynamic debug wrapper. vchiq_loud_error_*() has been removed
as a part of this patch and replaced with dev_err (so that
they directly end up in kernel log, even if dynamic debug
isn't enabled), which serves the purpose.

Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
Link: https://lore.kernel.org/r/20231024114428.443528-4-umang.jain@ideasonboard.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vc04_services: Drop VCHIQ_RETRY usage

Drop the usage of VCHIQ_RETRY vchiq_status enum type in most of the
places and replace it with -EAGAIN. The exception to this replacement
is vchiq_send_remote_use() and vchiq_send_remote_use_active() which will
be addressed in the subsequent commit.

This patch acts as intermediatory to address the TODO item:
* Get rid of custom function return values
for vc04_services/interface.

Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Link: https://lore.kernel.org/r/20221223122404.170585-5-umang.jain@ideasonboard.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vc04_services: Drop VCHIQ_ERROR usage

Drop the usage of VCHIQ_ERROR vchiq_status enum type. Replace it with
-EINVAL to report the error in most cases, -ENOMEM for out-of-memory
errors and -EHOSTDOWN for service shutdown.

This patch acts as intermediatory to address the TODO item:
* Get rid of custom function return values
for vc04_services/interface.

Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Link: https://lore.kernel.org/r/20221223122404.170585-4-umang.jain@ideasonboard.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vc04_services: Drop VCHIQ_SUCCESS usage

Drop the usage of VCHIQ_SUCCESS vchiq_status enum type. Replace it with
0 to report the success status.

This patch acts as intermediatory to address the TODO item:
* Get rid of custom function return values
for vc04_services/interface.

Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Link: https://lore.kernel.org/r/20221223122404.170585-3-umang.jain@ideasonboard.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vchiq_arm: pass vchiq instance to 'vchiq_get_client_id'

In order to remove the 'vchiq_states' global array, we need to pass the
vchiq_instance reference to the 'handle_to_service' function, as well as
to all functions that call 'handle_to_service'. This will allow
accessing the vchiq state through the vchiq instance instead of through
the global array.

'handle_to_service' is called by 'vchiq_get_client_id'. Therefore, pass
the vchiq instance reference to it.

Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Adrien Thierry <athierry@redhat.com>
Link: https://lore.kernel.org/r/20220518191126.60396-6-athierry@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vchiq_arm: pass vchiq instance to 'find_service_by_handle'

In order to remove the 'vchiq_states' global array, we need to pass the
vchiq_instance reference to the 'handle_to_service' function, as well as
to all functions that call 'handle_to_service'. This will allow
accessing the vchiq state through the vchiq instance instead of through
the global array.

'handle_to_service' is called by 'find_service_by_handle'. Therefore,
pass the vchiq instance reference to 'find_service_by_handle' and to its
callers.

Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Adrien Thierry <athierry@redhat.com>
Link: https://lore.kernel.org/r/20220518191126.60396-5-athierry@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vchiq_arm: get rid of global device structure

Get rid of the global g_dev structure.

This is part of an effort to address TODO item "Get rid of all non
essential global structures and create a proper per device structure"

I chose to pass the vchiq_instance around instead of the device
reference because in order to get rid of the 'vchiq_states' global array
in the future, we will need another way to access the vchiq_state in the
'handle_to_service' function. Therefore, we will need to pass the
vchiq_instance to it (or the vchiq_state), and also pass it to functions
higher up in the caller chain, such as 'vchiq_bulk_transmit' and friends
which are used in the bcm2835-audio consumer.

Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Adrien Thierry <athierry@redhat.com>
Link: https://lore.kernel.org/r/20220518191126.60396-3-athierry@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vchiq: replace usage of found with dedicated list iterator variable

To move the list iterator variable into the list_for_each_entry_*()
macro in the future it should be avoided to use the list iterator
variable after the loop body.

To *never* use the list iterator variable after the loop it was
concluded to use a separate iterator variable instead of a
found boolean [1].

This removes the need to use a found variable and simply checking if
the variable was set, can determine if the break/goto was hit.

Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/
Signed-off-by: Jakob Koschel <jakobkoschel@gmail.com>
Link: https://lore.kernel.org/r/20220324073024.65943-1-jakobkoschel@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vchiq_dev: Avoid unnecessary alloc in vchiq_ioc_create_service

There is no need to allocate the user service in case there is a VCHIQ
connection required, but not available. So simply check the error conditions
before doing an expensive memory allocation.

Reviewed-by: Nicolas Saenz Julienne <nsaenz@kernel.org>
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Link: https://lore.kernel.org/r/1642968143-19281-19-git-send-email-stefan.wahren@i2se.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vchiq: drop trailing semicolon in macro definition

As reported by checkpatch.pl, macro definitions should not use a trailing
semicolon.

Signed-off-by: Gaston Gonzalez <gascoar@gmail.com>
Link: https://lore.kernel.org/r/20211024212524.370078-6-gascoar@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vchiq_dev: cleanup code alignment issues

Fix code alignment issues.

Reported by checkpatch.pl

Signed-off-by: Gaston Gonzalez <gascoar@gmail.com>
Link: https://lore.kernel.org/r/20210912133751.269885-2-gascoar@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vchiq_dev: remove braces from if block

Remove unnecessary braces from if block.

Reported by checkpatch.pl

Signed-off-by: Gaston Gonzalez <gascoar@gmail.com>
Link: https://lore.kernel.org/r/20210912133751.269885-1-gascoar@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vchiq: convert to use a miscdevice

Using a struct class, a cdev, and another device just for a single minor
device is total overkill. Just use a dynamic misc device instead,
saving lots of logic and memory.

Cc: Nicolas Saenz Julienne <nsaenz@kernel.org>
Cc: Stefan Wahren <stefan.wahren@i2se.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Ojaswin Mujoo <ojaswin98@gmail.com>
Cc: Phil Elwell <phil@raspberrypi.com>
Cc: bcm-kernel-feedback-list@broadcom.com
Cc: linux-rpi-kernel@lists.infradead.org
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20210907115045.2206083-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

staging: vchiq: Move vchiq char driver to its own file

Split the initialization code of vchiq char driver and device files from
that of vchiq platform. The char driver code now resides in vchiq_dev.c
and the platform code resides in the original vchiq_arm.c file.

This commit focuses on separating the code into different files while
maintaining the same functionality. It does not completely decouple them
as the cdev init code is still called from the platform's vchiq_probe()
function.

Reviewed-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Ojaswin Mujoo <ojaswin98@gmail.com>
Link: https://lore.kernel.org/r/ed53690e217f631b746aad0585fccaa6fb1453c1.1626882325.git.ojaswin98@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>