linux.git/include/linux/soundwire/sdw.h, branch v6.1

Merge tag 'soundwire-6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/soundwire

2022-10-07T23:13:55+00:00

Pull soundwire updates from Vinod Koul:
 "Updates for Intel, Cadence and Qualcomm drivers:

   - another round of Intel driver cleanup to prepare for future code
     reorg which is expected in next cycle (Pierre-Louis Bossart)

   - bus unattach notifications processing during re-enumeration along
     with Cadence driver updates for this (Richard Fitzgerald)

   - Qualcomm driver updates to handle device0 status (Srinivas
     Kandagatla)"

* tag 'soundwire-6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/soundwire: (42 commits)
  soundwire: intel: add helper to stop bus
  soundwire: intel: introduce helpers to start bus
  soundwire: intel: introduce intel_shim_check_wake() helper
  soundwire: intel: simplify read ops assignment
  soundwire: intel: remove intel_init() wrapper
  soundwire: intel: move shim initialization before power up/down
  soundwire: intel: remove clock_stop parameter in intel_shim_init()
  soundwire: intel: move all PDI initialization under intel_register_dai()
  soundwire: intel: move DAI registration and debugfs init earlier
  soundwire: intel: simplify flow and use devm_ for DAI registration
  soundwire: intel: fix error handling on dai registration issues
  soundwire: cadence: Simplify error paths in cdns_xfer_msg()
  soundwire: cadence: Fix error check in cdns_xfer_msg()
  soundwire: cadence: Write to correct address for each FIFO chunk
  soundwire: bus: Fix wrong port number in sdw_handle_slave_alerts()
  soundwire: qcom: do not send status of device 0 during alert
  soundwire: qcom: update status from device id 1
  soundwire: cadence: Don't overwrite msg->buf during write commands
  soundwire: bus: Don't exit early if no device IDs were programmed
  soundwire: cadence: Fix lost ATTACHED interrupts when enumerating
  ...

soundwire: bus: allow device number to be unique at system level

2022-08-30T04:46:41+00:00

The SoundWire specification allows the device number to be allocated
at will. When a system includes multiple SoundWire links, the device
number scope is limited to the link to which the device is attached.

However, for integration/debug it can be convenient to have a unique
device number across the system. This patch adds a 'dev_num_ida_min'
field at the bus level, which when set will be used to allocate an
IDA.

The allocation happens when a hardware device reports as ATTACHED. If
any error happens during the enumeration, the allocated IDA is not
freed - the device number will be reused if/when the device re-joins
the bus. The IDA is only freed when the Linux device is unregistered.

Signed-off-by: Pierre-Louis Bossart 
Reviewed-by: Ranjani Sridharan 
Reviewed-by: Rander Wang 
Signed-off-by: Bard Liao 
Link: https://lore.kernel.org/r/20220823045004.2670658-3-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul

soundwire: add sdw_show_ping_status() helper

2022-08-17T12:00:54+00:00

This helper provides an optional delay parameter to wait for devices
to resync in case of errors, and checks that devices are indeed
attached on the bus.

Signed-off-by: Pierre-Louis Bossart 
Reviewed-by: Rander Wang 
Signed-off-by: Bard Liao 
Acked-By: Vinod Koul 
Link: https://lore.kernel.org/r/20220714011043.46059-4-yung-chuan.liao@linux.intel.com
Signed-off-by: Mark Brown

soundwire: add read_ping_status helper definition in manager ops

2022-08-17T12:00:52+00:00

The existing manager ops provide callbacks to transfer read/write
commands, but don't allow for direct access to PING status
register. This is accessible in all existing IP, and would help
diagnose timeouts or resume issues by reporting the 'true' status
instead of the internal status reported by the IP.

Signed-off-by: Pierre-Louis Bossart 
Reviewed-by: Rander Wang 
Signed-off-by: Bard Liao 
Acked-By: Vinod Koul 
Link: https://lore.kernel.org/r/20220714011043.46059-2-yung-chuan.liao@linux.intel.com
Signed-off-by: Mark Brown

soundwire: peripheral: remove useless ops pointer

2022-07-06T07:04:21+00:00

Now that we are using the ops structure directly from the driver,
there are no users left of this ops pointer.

Signed-off-by: Pierre-Louis Bossart 
Reviewed-by: Rander Wang 
Reviewed-by: Ranjani Sridharan 
Reviewed-by: Bard Liao 
Reviewed-by: Péter Ujfalusi 
Link: https://lore.kernel.org/r/20220621225641.221170-3-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul

soundwire: revisit driver bind/unbind and callbacks

2022-07-06T07:04:21+00:00

In the SoundWire probe, we store a pointer from the driver ops into
the 'slave' structure. This can lead to kernel oopses when unbinding
codec drivers, e.g. with the following sequence to remove machine
driver and codec driver.

/sbin/modprobe -r snd_soc_sof_sdw
/sbin/modprobe -r snd_soc_rt711

The full details can be found in the BugLink below, for reference the
two following examples show different cases of driver ops/callbacks
being invoked after the driver .remove().

kernel: BUG: kernel NULL pointer dereference, address: 0000000000000150
kernel: Workqueue: events cdns_update_slave_status_work [soundwire_cadence]
kernel: RIP: 0010:mutex_lock+0x19/0x30
kernel: Call Trace:
kernel: ? sdw_handle_slave_status+0x426/0xe00 [soundwire_bus 94ff184bf398570c3f8ff7efe9e32529f532e4ae]
kernel: ? newidle_balance+0x26a/0x400
kernel: ? cdns_update_slave_status_work+0x1e9/0x200 [soundwire_cadence 1bcf98eebe5ba9833cd433323769ac923c9c6f82]

kernel: BUG: unable to handle page fault for address: ffffffffc07654c8
kernel: Workqueue: pm pm_runtime_work
kernel: RIP: 0010:sdw_bus_prep_clk_stop+0x6f/0x160 [soundwire_bus]
kernel: Call Trace:
kernel:
kernel: sdw_cdns_clock_stop+0xb5/0x1b0 [soundwire_cadence 1bcf98eebe5ba9833cd433323769ac923c9c6f82]
kernel: intel_suspend_runtime+0x5f/0x120 [soundwire_intel aca858f7c87048d3152a4a41bb68abb9b663a1dd]
kernel: ? dpm_sysfs_remove+0x60/0x60

This was not detected earlier in Intel tests since the tests first
remove the parent PCI device and shut down the bus. The sequence
above is a corner case which keeps the bus operational but without a
driver bound.

While trying to solve this kernel oopses, it became clear that the
existing SoundWire bus does not deal well with the unbind case.

Commit 528be501b7d4a ("soundwire: sdw_slave: add probe_complete structure and new fields")
added a 'probed' status variable and a 'probe_complete'
struct completion. This status is however not reset on remove and
likewise the 'probe complete' is not re-initialized, so the
bind/unbind/bind test cases would fail. The timeout used before the
'update_status' callback was also a bad idea in hindsight, there
should really be no timing assumption as to if and when a driver is
bound to a device.

An initial draft was based on device_lock() and device_unlock() was
tested. This proved too complicated, with deadlocks created during the
suspend-resume sequences, which also use the same device_lock/unlock()
as the bind/unbind sequences. On a CometLake device, a bad DSDT/BIOS
caused spurious resumes and the use of device_lock() caused hangs
during suspend. After multiple weeks or testing and painful
reverse-engineering of deadlocks on different devices, we looked for
alternatives that did not interfere with the device core.

A bus notifier was used successfully to keep track of DRIVER_BOUND and
DRIVER_UNBIND events. This solved the bind-unbind-bind case in tests,
but it can still be defeated with a theoretical corner case where the
memory is freed by a .remove while the callback is in use. The
notifier only helps make sure the driver callbacks are valid, but not
that the memory allocated in probe remains valid while the callbacks
are invoked.

This patch suggests the introduction of a new 'sdw_dev_lock' mutex
protecting probe/remove and all driver callbacks. Since this mutex is
'local' to SoundWire only, it does not interfere with existing locks
and does not create deadlocks. In addition, this patch removes the
'probe_complete' completion, instead we directly invoke the
'update_status' from the probe routine. That removes any sort of
timing dependency and a much better support for the device/driver
model, the driver could be bound before the bus started, or eons after
the bus started and the hardware would be properly initialized in all
cases.

BugLink: https://github.com/thesofproject/linux/issues/3531
Fixes: 56d4fe31af77 ("soundwire: Add MIPI DisCo property helpers")
Fixes: 528be501b7d4a ("soundwire: sdw_slave: add probe_complete structure and new fields")
Signed-off-by: Pierre-Louis Bossart
Reviewed-by: Rander Wang
Reviewed-by: Ranjani Sridharan
Reviewed-by: Bard Liao
Reviewed-by: Péter Ujfalusi
Link: https://lore.kernel.org/r/20220621225641.221170-2-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul

soundwire: add flag to ignore all command/control for mockup devices

2021-08-02T05:38:22+00:00

SoundWire mockup devices don't take part in the command/control
protocol, so all commands will complete with -ENODATA or
Command_Ignored results. With a flag, we can suppress such errors in
the bus management and make it appear as if all read/writes succeed.

Signed-off-by: Pierre-Louis Bossart 
Reviewed-by: Rander Wang 
Signed-off-by: Bard Liao 
Link: https://lore.kernel.org/r/20210714032209.11284-7-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul

Merge tag 'char-misc-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

2021-07-05T20:42:16+00:00

Pull char / misc driver updates from Greg KH:
 "Here is the big set of char / misc and other driver subsystem updates
  for 5.14-rc1. Included in here are:

   - habanalabs driver updates

   - fsl-mc driver updates

   - comedi driver updates

   - fpga driver updates

   - extcon driver updates

   - interconnect driver updates

   - mei driver updates

   - nvmem driver updates

   - phy driver updates

   - pnp driver updates

   - soundwire driver updates

   - lots of other tiny driver updates for char and misc drivers

  This is looking more and more like the "various driver subsystems
  mushed together" tree...

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'char-misc-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (292 commits)
  mcb: Use DEFINE_RES_MEM() helper macro and fix the end address
  PNP: moved EXPORT_SYMBOL so that it immediately followed its function/variable
  bus: mhi: pci-generic: Add missing 'pci_disable_pcie_error_reporting()' calls
  bus: mhi: Wait for M2 state during system resume
  bus: mhi: core: Fix power down latency
  intel_th: Wait until port is in reset before programming it
  intel_th: msu: Make contiguous buffers uncached
  intel_th: Remove an unused exit point from intel_th_remove()
  stm class: Spelling fix
  nitro_enclaves: Set Bus Master for the NE PCI device
  misc: ibmasm: Modify matricies to matrices
  misc: vmw_vmci: return the correct errno code
  siox: Simplify error handling via dev_err_probe()
  fpga: machxo2-spi: Address warning about unused variable
  lkdtm/heap: Add init_on_alloc tests
  selftests/lkdtm: Enable various testable CONFIGs
  lkdtm: Add CONFIG hints in errors where possible
  lkdtm: Enable DOUBLE_FAULT on all architectures
  lkdtm/heap: Add vmalloc linear overflow test
  lkdtm/bugs: XFAIL UNALIGNED_LOAD_STORE_WRITE
  ...

soundwire: export sdw_update() and sdw_update_no_pm()

2021-06-21T12:00:42+00:00

We currently export sdw_read() and sdw_write() but the sdw_update()
and sdw_update_no_pm() are currently available only to the bus
code. This was missed in an earlier contribution.

Export both functions so that codec drivers can perform
read-modify-write operations without duplicating the code.

Fixes: b04c975e654c ('soundwire: bus: use sdw_update_no_pm when initializing a device')
Signed-off-by: Pierre-Louis Bossart 
Reviewed-by: Bard Liao 
Reviewed-by: Péter Ujfalusi 
Acked-By: Vinod Koul 
Link: https://lore.kernel.org/r/20210614180815.153711-2-pierre-louis.bossart@linux.intel.com
Signed-off-by: Mark Brown

soundwire: bus: Make sdw_nwrite() data pointer argument const

2021-06-20T11:16:14+00:00

Idiomatically, write functions should take const pointers to the
data buffer, as they don't change the data. They are also likely
to be called from functions that receive a const data pointer.

Internally the pointer is passed to function/structs shared with
the read functions, requiring a cast, but this is an implementation
detail that should be hidden by the public API.

Signed-off-by: Richard Fitzgerald 
Link: https://lore.kernel.org/r/20210616145901.29402-1-rf@opensource.cirrus.com
Signed-off-by: Vinod Koul