linux.git/drivers/soundwire, branch v6.5-rc2

soundwire: stream: Make master_list ordered to prevent deadlocks

2023-06-21T11:01:45+00:00

Always add buses to the stream->master_list in a fixed order.
The unique bus->id is used to order the adding of buses to the
list.

This prevents lockdep asserts and possible deadlocks on streams
that have multiple buses.

sdw_acquire_bus_lock() takes bus_lock in the order that buses
are listed in stream->master_list. do_bank_switch() takes all
the msg_lock in the same order.

To prevent a lockdep assert, and a possible real deadlock, the
relative order of taking these mutexes must always be the same.

For example, if a stream takes the mutexes in the order
(bus0, bus1) lockdep will assert if another stream takes them
in the order (bus1, bus0).

More complex relative ordering will also assert, for example
if two streams take (bus0, bus1) and (bus1, bus2), then a third
stream takes (bus2, bus0).

Previously sdw_stream_add_master() simply added the given bus
to the end of the list, requiring the caller to guarantee that
buses are added in a fixed order. This isn't reasonable or
necessary - it's an internal implementation detail that should
not be exposed by the API. It doesn't really make sense when
there could be multiple independent calling drivers, to say
"you must add your buses in the same order as a different driver,
that you don't know about, added them".

Signed-off-by: Richard Fitzgerald 
Reviewed-by: Pierre-Louis Bossart 
Link: https://lore.kernel.org/r/20230615141208.679011-2-rf@opensource.cirrus.com
Signed-off-by: Vinod Koul

soundwire: bus: Prevent lockdep asserts when stream has multiple buses

2023-06-21T11:01:44+00:00

Give the bus_lock and msg_lock of each bus a different unique key
so that it is possible to acquire the locks of multiple buses
without lockdep asserting a possible deadlock.

Using mutex_init() to initialize a mutex gives all those mutexes
the same lock class. Lockdep checking treats it as an error to
attempt to take a mutex while already holding a mutex of the same
class. This causes a lockdep assert when sdw_acquire_bus_lock()
attempts to lock multiple buses, and when do_bank_switch() takes
multiple msg_lock.

[  138.697350] WARNING: possible recursive locking detected
[  138.697366] 6.3.0-test #1 Tainted: G            E
[  138.697380] --------------------------------------------
[  138.697394] play/903 is trying to acquire lock:
[  138.697409] ffff99b8c41aa8c8 (&bus->bus_lock){+.+.}-{3:3}, at:
sdw_prepare_stream+0x52/0x2e0
[  138.697443]
               but task is already holding lock:
[  138.697468] ffff99b8c41af8c8 (&bus->bus_lock){+.+.}-{3:3}, at:
sdw_prepare_stream+0x52/0x2e0
[  138.697493]
               other info that might help us debug this:
[  138.697521]  Possible unsafe locking scenario:

[  138.697540]        CPU0
[  138.697550]        ----
[  138.697559]   lock(&bus->bus_lock);
[  138.697570]   lock(&bus->bus_lock);
[  138.697581]
                *** DEADLOCK ***

Giving each mutex a unique key allows multiple to be held
without triggering a lockdep assert. But note that it does not
allow them to be taken in one order then a different order.
If two mutexes are taken in the order A, B then they must
always be taken in that order otherwise they could deadlock.

Signed-off-by: Richard Fitzgerald 
Reviewed-by: Pierre-Louis Bossart 
Link: https://lore.kernel.org/r/20230615141208.679011-1-rf@opensource.cirrus.com
Signed-off-by: Vinod Koul

soundwire: qcom: fix storing port config out-of-bounds

2023-06-21T11:01:44+00:00

The 'qcom_swrm_ctrl->pconfig' has size of QCOM_SDW_MAX_PORTS (14),
however we index it starting from 1, not 0, to match real port numbers.
This can lead to writing port config past 'pconfig' bounds and
overwriting next member of 'qcom_swrm_ctrl' struct.  Reported also by
smatch:

  drivers/soundwire/qcom.c:1269 qcom_swrm_get_port_config() error: buffer overflow 'ctrl->pconfig' 14 <= 14

Fixes: 9916c02ccd74 ("soundwire: qcom: cleanup internal port config indexing")
Cc: 
Reported-by: kernel test robot 
Reported-by: Dan Carpenter 
Link: https://lore.kernel.org/r/202305201301.sCJ8UDKV-lkp@intel.com/
Signed-off-by: Krzysztof Kozlowski 
Reviewed-by: Konrad Dybcio 
Link: https://lore.kernel.org/r/20230601102525.609627-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Vinod Koul

soundwire: intel_ace2x: fix SND_SOC_SOF_HDA_MLINK dependency

2023-06-21T10:49:44+00:00

The ace2x driver can be build with or without mlink support, but
when SND_SOC_SOF_HDA_MLINK is set to =m and soundwire is built-in,
it fails with a link error:

ld.lld: error: undefined symbol: hdac_bus_eml_sdw_wait_syncpu_unlocked
>>> referenced by intel_ace2x.c
>>>               drivers/soundwire/intel_ace2x.o:(intel_link_power_up) in archive vmlinux.a

ld.lld: error: undefined symbol: hdac_bus_eml_sdw_sync_arm_unlocked
>>> referenced by intel_ace2x.c
>>>               drivers/soundwire/intel_ace2x.o:(intel_sync_arm) in archive vmlinux.a

Add a Kconfig dependency that prevents that broken configuration but
still allows soundwire to be a loadable module instead.

Fixes: 4d1e2464a1104 ("soundwire: intel_ace2x: add sync_arm/sync_go helpers")
Signed-off-by: Arnd Bergmann 
Link: https://lore.kernel.org/r/20230616090932.2714714-1-arnd@kernel.org
Signed-off-by: Vinod Koul

soundwire: debugfs: Add missing SCP registers

2023-06-08T11:40:32+00:00

SCP registers needs to be updated to accommodate additional
register entries as per the Soundwire 1.2 specification.

Signed-off-by: Uday M Bhat 
Signed-off-by: Yong Zhi 
Reviewed-by: Pierre-Louis Bossart 
Reviewed-by: Ranjani Sridharan 
Signed-off-by: Bard Liao 
Link: https://lore.kernel.org/r/20230607020632.1030309-1-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul

soundwire: stream: Remove unnecessary gotos

2023-06-08T11:39:11+00:00

There is a lot of code using gotos to skip small sections of code, this
is a fairly dubious use of a goto, especially when the level of
intentation is really low. Most of this code doesn't even breach 80
characters when naively shifted over.

Simplify the code a bit, by replacing these unnecessary gotos with
simple ifs.

Signed-off-by: Charles Keepax 
Reviewed-by: Pierre-Louis Bossart 
Link: https://lore.kernel.org/r/20230602101140.2040141-5-ckeepax@opensource.cirrus.com
Signed-off-by: Vinod Koul

soundwire: stream: Invert logic on runtime alloc flags

2023-06-08T11:39:11+00:00

sdw_stream_add_slave/master have flags to indicate if the master or
slave runtime where allocated in that call to the function. Currently
these flags are cleared on all the paths where the runtime is not
allocated, it is more logic and simpler to set the flag on the one path
where the runtime is allocated.

Signed-off-by: Charles Keepax 
Reviewed-by: Pierre-Louis Bossart 
Link: https://lore.kernel.org/r/20230602101140.2040141-4-ckeepax@opensource.cirrus.com
Signed-off-by: Vinod Koul

soundwire: stream: Remove unneeded checks for NULL bus

2023-06-08T11:39:11+00:00

Version of the code prior to commit d014688eb373 ("soundwire: stream:
remove bus->dev from logs on multiple buses"), used bus->dev in the
error message after do_bank_switch, this necessitated some checking to
ensure the bus pointer was valid. As the code no longer uses bus->dev
said checking is now redundant, so remove it.

Signed-off-by: Charles Keepax 
Reviewed-by: Pierre-Louis Bossart 
Link: https://lore.kernel.org/r/20230602101140.2040141-3-ckeepax@opensource.cirrus.com
Signed-off-by: Vinod Koul

soundwire: bandwidth allocation: Remove pointless variable

2023-06-08T11:39:11+00:00

The block_offset variable in _sdw_compute_port_params adds nothing
either functionally or in terms of code clarity, remove it.

Reviewed-by: Pierre-Louis Bossart 
Signed-off-by: Charles Keepax 
Link: https://lore.kernel.org/r/20230602101140.2040141-2-ckeepax@opensource.cirrus.com
Signed-off-by: Vinod Koul

Merge branch 'fixes' into next

2023-06-08T11:38:33+00:00

This resolves dependecy for the series
20230602101140.2040141-1-ckeepax@opensource.cirrus.com