<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/include/linux/soundwire, branch v5.14</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Merge tag 'char-misc-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc</title>
<updated>2021-07-05T20:42:16+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2021-07-05T20:42:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=eed0218e8cae9fcd186c30e9fcf5fe46a87e056e'/>
<id>eed0218e8cae9fcd186c30e9fcf5fe46a87e056e</id>
<content type='text'>
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
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
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
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>soundwire: export sdw_update() and sdw_update_no_pm()</title>
<updated>2021-06-21T12:00:42+00:00</updated>
<author>
<name>Pierre-Louis Bossart</name>
<email>pierre-louis.bossart@linux.intel.com</email>
</author>
<published>2021-06-14T18:08:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=d38ebaf2c88442a830d402fa7805ddbb60c4cd0c'/>
<id>d38ebaf2c88442a830d402fa7805ddbb60c4cd0c</id>
<content type='text'>
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 &lt;pierre-louis.bossart@linux.intel.com&gt;
Reviewed-by: Bard Liao &lt;bard.liao@intel.com&gt;
Reviewed-by: Péter Ujfalusi &lt;peter.ujfalusi@linux.intel.com&gt;
Acked-By: Vinod Koul &lt;vkoul@kernel.org&gt;
Link: https://lore.kernel.org/r/20210614180815.153711-2-pierre-louis.bossart@linux.intel.com
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
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 &lt;pierre-louis.bossart@linux.intel.com&gt;
Reviewed-by: Bard Liao &lt;bard.liao@intel.com&gt;
Reviewed-by: Péter Ujfalusi &lt;peter.ujfalusi@linux.intel.com&gt;
Acked-By: Vinod Koul &lt;vkoul@kernel.org&gt;
Link: https://lore.kernel.org/r/20210614180815.153711-2-pierre-louis.bossart@linux.intel.com
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>soundwire: bus: Make sdw_nwrite() data pointer argument const</title>
<updated>2021-06-20T11:16:14+00:00</updated>
<author>
<name>Richard Fitzgerald</name>
<email>rf@opensource.cirrus.com</email>
</author>
<published>2021-06-16T14:59:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=031e668bc1ad7ccdbfb2b67b838bb6b7cc44ecf3'/>
<id>031e668bc1ad7ccdbfb2b67b838bb6b7cc44ecf3</id>
<content type='text'>
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 &lt;rf@opensource.cirrus.com&gt;
Link: https://lore.kernel.org/r/20210616145901.29402-1-rf@opensource.cirrus.com
Signed-off-by: Vinod Koul &lt;vkoul@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
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 &lt;rf@opensource.cirrus.com&gt;
Link: https://lore.kernel.org/r/20210616145901.29402-1-rf@opensource.cirrus.com
Signed-off-by: Vinod Koul &lt;vkoul@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>soundwire: intel: move to auxiliary bus</title>
<updated>2021-06-14T04:42:26+00:00</updated>
<author>
<name>Pierre-Louis Bossart</name>
<email>pierre-louis.bossart@linux.intel.com</email>
</author>
<published>2021-05-11T05:21:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=29a269c6f54825c643a5c35762a2829ba5be67f6'/>
<id>29a269c6f54825c643a5c35762a2829ba5be67f6</id>
<content type='text'>
Now that the auxiliary_bus exists, there's no reason to use platform
devices as children of a PCI device any longer.

This patch refactors the code by extending a basic auxiliary device
with Intel link-specific structures that need to be passed between
controller and link levels. This refactoring is much cleaner with no
need for cross-pointers between device and link structures.

Note that the auxiliary bus API has separate init and add steps, which
requires more attention in the error unwinding paths. The main loop
needs to deal with kfree() and auxiliary_device_uninit() for the
current iteration before jumping to the common label which releases
everything allocated in prior iterations.

Signed-off-by: Pierre-Louis Bossart &lt;pierre-louis.bossart@linux.intel.com&gt;
Reviewed-by: Guennadi Liakhovetski &lt;guennadi.liakhovetski@linux.intel.com&gt;
Reviewed-by: Ranjani Sridharan &lt;ranjani.sridharan@linux.intel.com&gt;
Signed-off-by: Bard Liao &lt;yung-chuan.liao@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20210511052132.28150-1-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul &lt;vkoul@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Now that the auxiliary_bus exists, there's no reason to use platform
devices as children of a PCI device any longer.

This patch refactors the code by extending a basic auxiliary device
with Intel link-specific structures that need to be passed between
controller and link levels. This refactoring is much cleaner with no
need for cross-pointers between device and link structures.

Note that the auxiliary bus API has separate init and add steps, which
requires more attention in the error unwinding paths. The main loop
needs to deal with kfree() and auxiliary_device_uninit() for the
current iteration before jumping to the common label which releases
everything allocated in prior iterations.

Signed-off-by: Pierre-Louis Bossart &lt;pierre-louis.bossart@linux.intel.com&gt;
Reviewed-by: Guennadi Liakhovetski &lt;guennadi.liakhovetski@linux.intel.com&gt;
Reviewed-by: Ranjani Sridharan &lt;ranjani.sridharan@linux.intel.com&gt;
Signed-off-by: Bard Liao &lt;yung-chuan.liao@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20210511052132.28150-1-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul &lt;vkoul@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>soundwire: add missing kernel-doc description</title>
<updated>2021-05-11T12:20:32+00:00</updated>
<author>
<name>Pierre-Louis Bossart</name>
<email>pierre-louis.bossart@linux.intel.com</email>
</author>
<published>2021-05-11T03:00:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=448df2d8fcab6cc50e0de4679ce3afe2ece282f2'/>
<id>448df2d8fcab6cc50e0de4679ce3afe2ece282f2</id>
<content type='text'>
For some reason we never added a description for the clk_stop
callback.

Signed-off-by: Pierre-Louis Bossart &lt;pierre-louis.bossart@linux.intel.com&gt;
Reviewed-by: Guennadi Liakhovetski &lt;guennadi.liakhovetski@linux.intel.com&gt;
Reviewed-by: Rander Wang &lt;rander.wang@intel.com&gt;
Signed-off-by: Bard Liao &lt;yung-chuan.liao@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20210511030048.25622-3-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul &lt;vkoul@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
For some reason we never added a description for the clk_stop
callback.

Signed-off-by: Pierre-Louis Bossart &lt;pierre-louis.bossart@linux.intel.com&gt;
Reviewed-by: Guennadi Liakhovetski &lt;guennadi.liakhovetski@linux.intel.com&gt;
Reviewed-by: Rander Wang &lt;rander.wang@intel.com&gt;
Signed-off-by: Bard Liao &lt;yung-chuan.liao@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20210511030048.25622-3-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul &lt;vkoul@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>soundwire: bus: only use CLOCK_STOP_MODE0 and fix confusions</title>
<updated>2021-05-11T12:20:32+00:00</updated>
<author>
<name>Pierre-Louis Bossart</name>
<email>pierre-louis.bossart@linux.intel.com</email>
</author>
<published>2021-05-11T03:00:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=345e9f5ca798600e44c0843646621f2804eb99f4'/>
<id>345e9f5ca798600e44c0843646621f2804eb99f4</id>
<content type='text'>
Existing devices and implementations only support the required
CLOCK_STOP_MODE0. All the code related to CLOCK_STOP_MODE1 has not
been tested and is highly questionable, with a clear confusion between
CLOCK_STOP_MODE1 and the simple clock stop state machine.

This patch removes all usages of CLOCK_STOP_MODE1 - which has no
impact on any solution - and fixes the use of the simple clock stop
state machine. The resulting code should be a lot more symmetrical and
easier to maintain.

Note that CLOCK_STOP_MODE1 is not supported in the SoundWire Device
Class specification so it's rather unlikely that we need to re-add
this mode later.

Signed-off-by: Pierre-Louis Bossart &lt;pierre-louis.bossart@linux.intel.com&gt;
Reviewed-by: Guennadi Liakhovetski &lt;guennadi.liakhovetski@linux.intel.com&gt;
Reviewed-by: Rander Wang &lt;rander.wang@intel.com&gt;
Signed-off-by: Bard Liao &lt;yung-chuan.liao@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20210511030048.25622-2-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul &lt;vkoul@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Existing devices and implementations only support the required
CLOCK_STOP_MODE0. All the code related to CLOCK_STOP_MODE1 has not
been tested and is highly questionable, with a clear confusion between
CLOCK_STOP_MODE1 and the simple clock stop state machine.

This patch removes all usages of CLOCK_STOP_MODE1 - which has no
impact on any solution - and fixes the use of the simple clock stop
state machine. The resulting code should be a lot more symmetrical and
easier to maintain.

Note that CLOCK_STOP_MODE1 is not supported in the SoundWire Device
Class specification so it's rather unlikely that we need to re-add
this mode later.

Signed-off-by: Pierre-Louis Bossart &lt;pierre-louis.bossart@linux.intel.com&gt;
Reviewed-by: Guennadi Liakhovetski &lt;guennadi.liakhovetski@linux.intel.com&gt;
Reviewed-by: Rander Wang &lt;rander.wang@intel.com&gt;
Signed-off-by: Bard Liao &lt;yung-chuan.liao@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20210511030048.25622-2-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul &lt;vkoul@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>soundwire: add static port mapping support</title>
<updated>2021-04-06T04:52:02+00:00</updated>
<author>
<name>Srinivas Kandagatla</name>
<email>srinivas.kandagatla@linaro.org</email>
</author>
<published>2021-03-15T16:56:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=f4022062e5417ab7228e95aec1a8687059a19db7'/>
<id>f4022062e5417ab7228e95aec1a8687059a19db7</id>
<content type='text'>
Some of the SoundWire device ports are statically mapped to Controller
ports during design, however there is no way to expose this information
to the controller. Controllers like Qualcomm ones use this info to setup
static bandwidth parameters for those ports.

A generic port allocation is not possible in this cases!
So this patch adds a new member m_port_map to struct sdw_slave to expose
this static map.

Signed-off-by: Srinivas Kandagatla &lt;srinivas.kandagatla@linaro.org&gt;
Reviewed-by: Pierre-Louis Bossart &lt;pierre-louis.bossart@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20210315165650.13392-2-srinivas.kandagatla@linaro.org
Signed-off-by: Vinod Koul &lt;vkoul@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Some of the SoundWire device ports are statically mapped to Controller
ports during design, however there is no way to expose this information
to the controller. Controllers like Qualcomm ones use this info to setup
static bandwidth parameters for those ports.

A generic port allocation is not possible in this cases!
So this patch adds a new member m_port_map to struct sdw_slave to expose
this static map.

Signed-off-by: Srinivas Kandagatla &lt;srinivas.kandagatla@linaro.org&gt;
Reviewed-by: Pierre-Louis Bossart &lt;pierre-louis.bossart@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20210315165650.13392-2-srinivas.kandagatla@linaro.org
Signed-off-by: Vinod Koul &lt;vkoul@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>soundwire: export sdw_compare_devid, sdw_extract_slave_id and sdw_slave_add</title>
<updated>2021-03-30T17:25:07+00:00</updated>
<author>
<name>Srinivas Kandagatla</name>
<email>srinivas.kandagatla@linaro.org</email>
</author>
<published>2021-03-30T14:47:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=01ad444e3be719f8ad13f136a9b0d301806183c8'/>
<id>01ad444e3be719f8ad13f136a9b0d301806183c8</id>
<content type='text'>
Exporting these three functions makes sense as it can be used by
other controllers like Qualcomm during auto-enumeration!

Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Signed-off-by: Srinivas Kandagatla &lt;srinivas.kandagatla@linaro.org&gt;
Link: https://lore.kernel.org/r/20210330144719.13284-8-srinivas.kandagatla@linaro.org
Signed-off-by: Vinod Koul &lt;vkoul@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Exporting these three functions makes sense as it can be used by
other controllers like Qualcomm during auto-enumeration!

Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Signed-off-by: Srinivas Kandagatla &lt;srinivas.kandagatla@linaro.org&gt;
Link: https://lore.kernel.org/r/20210330144719.13284-8-srinivas.kandagatla@linaro.org
Signed-off-by: Vinod Koul &lt;vkoul@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>soundwire: add definition for DPn BlockPackingMode</title>
<updated>2021-03-30T09:06:11+00:00</updated>
<author>
<name>Pierre-Louis Bossart</name>
<email>pierre-louis.bossart@linux.intel.com</email>
</author>
<published>2021-03-23T05:07:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=886ce97a36a05e7a9c9d5d894e72d31f50146f5d'/>
<id>886ce97a36a05e7a9c9d5d894e72d31f50146f5d</id>
<content type='text'>
For some reason we don't have an enum for this concept. Add
definitions following Table 102 of the SoundWire 1.2 specification.

Signed-off-by: Pierre-Louis Bossart &lt;pierre-louis.bossart@linux.intel.com&gt;
Reviewed-by: Rander Wang &lt;rander.wang@intel.com&gt;
Signed-off-by: Bard Liao &lt;yung-chuan.liao@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20210323050701.23760-2-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul &lt;vkoul@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
For some reason we don't have an enum for this concept. Add
definitions following Table 102 of the SoundWire 1.2 specification.

Signed-off-by: Pierre-Louis Bossart &lt;pierre-louis.bossart@linux.intel.com&gt;
Reviewed-by: Rander Wang &lt;rander.wang@intel.com&gt;
Signed-off-by: Bard Liao &lt;yung-chuan.liao@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20210323050701.23760-2-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul &lt;vkoul@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>soundwire: add master quirks for bus clash and parity</title>
<updated>2021-03-22T12:16:39+00:00</updated>
<author>
<name>Bard Liao</name>
<email>yung-chuan.liao@linux.intel.com</email>
</author>
<published>2021-03-02T08:27:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=5bb643c39b97c440b2981c69f05596c7ea868b73'/>
<id>5bb643c39b97c440b2981c69f05596c7ea868b73</id>
<content type='text'>
Currently quirks are only allowed for Slave devices. This patch
describes the need for two quirks at the Master level.

a) bus clash
The SoundWire specification allows a Slave device to report a bus clash
with the in-band interrupt mechanism when it detects a conflict while
driving a bitSlot it owns. This can be a symptom of an electrical conflict
or a programming error, and it's vital to detect reliably.

Unfortunately, on some platforms, bus clashes are randomly reported by
Slave devices after a bus reset, with an interrupt status set even before
the bus clash interrupt is enabled. These initial spurious interrupts are
not relevant and should optionally be filtered out, while leaving the
interrupt mechanism enabled to detect 'true' issues.

This patch suggests the addition of a Master level quirk to discard such
interrupts. The quirk should in theory have been added at the Slave level,
but since the problem was detected with different generations of Slave
devices it's hard to point to a specific IP. The problem might also be
board-dependent and hence dealing with a Master quirk is simpler.

b) parity

Additional tests on a new platform with the Maxim 98373 amplifier
showed a rare case where the parity interrupt is also thrown on
startup, at the same time as bus clashes. This issue only seems to
happen infrequently and was only observed during suspend-resume stress
tests while audio is streaming. We could make the problem go away by
adding a Slave-level quirk, but there is no evidence that the issue is
actually a Slave problem: the parity is provided by the Master, which
could also set an invalid parity in corner cases.

BugLink: https://github.com/thesofproject/linux/issues/2578
BugLink: https://github.com/thesofproject/linux/issues/2533
Co-developed-by: Pierre-Louis Bossart &lt;pierre-louis.bossart@linux.intel.com&gt;
Signed-off-by: Pierre-Louis Bossart &lt;pierre-louis.bossart@linux.intel.com&gt;
Signed-off-by: Bard Liao &lt;yung-chuan.liao@linux.intel.com&gt;
Reviewed-by: Guennadi Liakhovetski &lt;guennadi.liakhovetski@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20210302082720.12322-2-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul &lt;vkoul@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Currently quirks are only allowed for Slave devices. This patch
describes the need for two quirks at the Master level.

a) bus clash
The SoundWire specification allows a Slave device to report a bus clash
with the in-band interrupt mechanism when it detects a conflict while
driving a bitSlot it owns. This can be a symptom of an electrical conflict
or a programming error, and it's vital to detect reliably.

Unfortunately, on some platforms, bus clashes are randomly reported by
Slave devices after a bus reset, with an interrupt status set even before
the bus clash interrupt is enabled. These initial spurious interrupts are
not relevant and should optionally be filtered out, while leaving the
interrupt mechanism enabled to detect 'true' issues.

This patch suggests the addition of a Master level quirk to discard such
interrupts. The quirk should in theory have been added at the Slave level,
but since the problem was detected with different generations of Slave
devices it's hard to point to a specific IP. The problem might also be
board-dependent and hence dealing with a Master quirk is simpler.

b) parity

Additional tests on a new platform with the Maxim 98373 amplifier
showed a rare case where the parity interrupt is also thrown on
startup, at the same time as bus clashes. This issue only seems to
happen infrequently and was only observed during suspend-resume stress
tests while audio is streaming. We could make the problem go away by
adding a Slave-level quirk, but there is no evidence that the issue is
actually a Slave problem: the parity is provided by the Master, which
could also set an invalid parity in corner cases.

BugLink: https://github.com/thesofproject/linux/issues/2578
BugLink: https://github.com/thesofproject/linux/issues/2533
Co-developed-by: Pierre-Louis Bossart &lt;pierre-louis.bossart@linux.intel.com&gt;
Signed-off-by: Pierre-Louis Bossart &lt;pierre-louis.bossart@linux.intel.com&gt;
Signed-off-by: Bard Liao &lt;yung-chuan.liao@linux.intel.com&gt;
Reviewed-by: Guennadi Liakhovetski &lt;guennadi.liakhovetski@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20210302082720.12322-2-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul &lt;vkoul@kernel.org&gt;
</pre>
</div>
</content>
</entry>
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