Test modes are required for all SoundWire IP, and help debug
integration issues. In theory each port can be configured with a
different mode but to simplify this patch only offers separate
configurations for the Master and Slave ports - this covers 99% of the
intended cases during platform integration.
The test mode value is set via platform-specific ways.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20200920193207.31241-2-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
This algorithm computes bus parameters like clock frequency, frame
shape and port transport parameters based on active stream(s) running
on the bus.
Developers can also implement their own .compute_params() callback for
specific resource management algorithm, and set if before calling
sdw_add_bus_master()
Credits: this patch is based on an earlier internal contribution by
Vinod Koul, Sanyog Kale, Shreyas Nc and Hardik Shah. All hard-coded
values were removed from the initial contribution to use BIOS
information instead.
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Acked-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20200908131520.5712-1-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
If a Slave device reports with a quirk that its initial parity check
may be incorrect, filter it but keep the parity checks active in
steady state.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Reviewed-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
Link: https://lore.kernel.org/r/20200908134521.6781-5-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Some Slaves report incorrect information in their interrupt status
registers after a master/bus reset, track the initial interrupt
handling so that quirks can be introduced to filter out incorrect
information while keeping interrupts enabled in steady state.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Reviewed-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
Link: https://lore.kernel.org/r/20200908134521.6781-4-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Add a slave-level property and program the SCP_INT1_MASK as desired by
the codec driver. Since there is no DisCo property this has to be an
implementation-specific firmware property or hard-coded in the driver.
The only functionality change is that implementation-defined
interrupts are no longer set for amplifiers - those interrupts are
typically for jack detection or acoustic event detection/hotwording.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Tested-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Reviewed-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
Acked-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20200908134521.6781-2-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
soundwire had defined SDW_REG_SHIFT to calculate shift values for
bitmasks, but now that we have better things in bitfield.h, remove this.
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Tested-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20200903114504.1202143-10-vkoul@kernel.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Soundwire addr is a 52bit value encoding link, version, unique id,
mfg id, part id and class id. Define bit masks for these and use
FIELD_GET() to extract these fields.
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Tested-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20200903114504.1202143-2-vkoul@kernel.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Hardware-based synchronization is typically required when the
bus->multi_link flag is set.
On Intel platforms, when the Cadence IP is configured in 'Multi Master
Mode', the hardware synchronization is required even when a stream
only uses a single segment. The existing code only deal with hardware
synchronization when a stream uses more than one segment so to remain
backwards compatible we add a configuration threshold. For Intel cases
this threshold will be set to one, other platforms may be able to use
the SSP-based sync in those cases.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20200901150556.19432-6-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The existing code allocates memory for the total number of ports.
This only works if the ports are contiguous, but will break if e.g. a
Devices uses port0, 1, and 14. The port_ready[] array would contain 3
elements, which would lead to an out-of-bounds access. Conversely in
other cases, the wrong port index would be used leading to timeouts on
prepare.
This can be fixed by allocating for the worst-case of 15
ports (DP0..DP14). In addition since the number is now fixed, we can
use an array instead of a dynamic allocation.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@linux.intel.com>
Reviewed-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
Link: https://lore.kernel.org/r/20200831134318.11443-4-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Somehow the existing code is not aligned with the steps described in
the documentation, refactor code and make sure the register
programming sequences are correct. Also add missing power-up,
power-down and wake capabilities (the last two are used in follow-up
patches but introduced here for consistency).
Some of the SHIM registers exposed fields that are link specific, and
in addition some of the power-related registers (SPA/CPA) take time to
be updated. Uncontrolled access leads to timeouts or errors. Add a
mutex, shared by all links, so that all accesses to such registers are
serialized, and follow a pattern of read-modify-write.
This includes making sure SHIM_SYNC is programmed only once, before
the first master is powered on. We use a 'shim_mask' field, shared
between all links and protected by a mutex, to deal with power-up and
power-down sequences.
Note that the SYNCPRD value is tied only to the XTAL value and not the
current bus frequency or the frame rate.
BugLink: https://github.com/thesofproject/linux/issues/1555
Signed-off-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20200716150947.22119-3-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Not sure how this went undetected for years.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20200714213744.24674-3-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Table 110 "Port Data Modes" of the SoundWire 1.2 specification lists
PRBS as b01 and Static_1 as b11. The existing headers swapped the two
values, fix.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20200714213744.24674-2-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
To handle streams at the dailink level, expose two helpers that will
be called from machine drivers.
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20200630184356.24939-3-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The SoundWire 1.2 specification adds new registers to allow for
seamless clock changes while audio transfers are on-going. Program
them following the specification.
Note that dynamic clock changes are not supported for now, this only
adds the register initialization.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Reviewed-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20200608205436.2402-5-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The SoundWire 1.2 specification adds new capabilities that were not
present in previous version, such as the class ID.
To enable support for class drivers, and well as drivers that address
a specific version, all fields of the sdw_device_id structure need to
be exposed. For SoundWire 1.0 and 1.1 devices, a wildcard is used so
class and version information are ignored.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@linux.intel.com>
Reviewed-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20200608205436.2402-4-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Use more meaningful member names in preparation for sysfs support.
No functionality change.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20200518203551.2053-2-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
In the existing SoundWire code, Master Devices are not explicitly
represented - only SoundWire Slave Devices are exposed (the use of
capital letters follows the SoundWire specification conventions).
With the existing code, the bus is handled without using a proper device,
and bus->dev typically points to a platform device. The right thing to
do as discussed in multiple reviews is use a device for each bus.
The sdw_master_device addition is done with minimal internal plumbing
and not exposed externally. The existing API based on
sdw_bus_master_add() and sdw_bus_master_delete() will deal with the
sdw_master_device life cycle, which minimizes changes to existing
drivers.
Note that the Intel code will be modified in follow-up patches (no
impact on any platform since the connection with ASoC is not supported
upstream so far).
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Acked-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20200518174322.31561-5-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
this is a preparatory patch before the introduction of the
sdw_master_type. The SoundWire slave support is slightly modified with
the use of a sdw_slave_type, and the uevent handling move to
slave.c (since it's not necessary for the master).
No functionality change other than moving code around.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Acked-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20200518174322.31561-3-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
In preparation for future extensions, rename functions to use
sdw_bus_master prefix and add a parent and fwnode argument to
sdw_bus_master_add to help with device registration in follow-up
patches.
No functionality change, just renames and additional arguments.
The Intel code is currently unused, the two additional arguments are
only needed for compilation.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Acked-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20200518174322.31561-2-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
According to SoundWire Specification Version 1.2.
"A Data Port number X (in the range 0-14) which supports only one
value of WordLength may implement the WordLength field in the
DPX_BlockCtrl1 Register as Read-Only, returning the fixed value of
WordLength in response to reads."
As WSA881x interfaces in PDM mode making the only field "WordLength"
in DPX_BlockCtrl1" fixed and read-only. Behaviour of writing to this
register on WSA881x soundwire slave with Qualcomm Soundwire Controller
is throwing up an error. Not sure how other controllers deal with
writing to readonly registers, but this patch provides a way to avoid
writes to DPN_BlockCtrl1 register by providing a read_only_wordlength
flag in struct sdw_dpn_prop
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200311113545.23773-2-srinivas.kandagatla@linaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Move bit extractors to macros, so that the definitions can be used by
other drivers parsing the MIPI definitions extracted from firmware
tables (ACPI or DT).
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200225170041.23644-4-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
SoundWire supports two clock stop modes. Add support to handle the
clock stop modes and add pm_runtime calls in the bus.
Credits: this patch is based on an earlier internal contribution by
Vinod Koul, Sanyog Kale, Shreyas Nc and Hardik Shah.
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Signed-off-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200115000844.14695-10-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The existing link_mask flag is no longer sufficient to detect the
hardware and identify which topology file and a machine driver to load.
By reporting the slave_ids exposed in ACPI tables, the parent SOF
driver will be able to compare against a set of static configurations.
This patch only adds the interface change, the functionality is added
in future patches.
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200110220016.30887-1-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
If the programming of the dev_number fails due to an IO error, a new
device_number will be assigned, resulting in a leak.
Make sure we only assign a device_number once per Slave device.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200113225637.17313-1-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Due to power rail dependencies, the SoundWire Master driver cannot
make decisions on its own when entering pm runtime suspend.
Add quirk mask for each link, so that the SOF parent driver can inform
the SoundWire master driver of the desired behavior:
a) leave clock on
b) power-off instead of clock stop
c) power-off if all devices cannot generate wakes
d) force bus reset on clock restart
Note that for now the interface with the SOF driver relies on a single
mask for all links. If needed, the interface might be modified at a
later point to provide more freedom. The code at the lower level does
not assume any commonality between links.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20191212014507.28050-12-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Some of the Intel SoundWire SHIM registers contain fields for
different links. Without protection, the master drivers for the
different links will access these shared registers, leading to invalid
configurations and timeouts (specifically when changing CPA/SPA
power-related registers and polling for the changes to be applied).
A mutex is added to make sure all rmw access to those registers are
serialized.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20191212014507.28050-11-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
In ClockStop mode, the PCI device will be notified of a wake, which
will be handled from an interrupt thread.
Signed-off-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20191212014507.28050-10-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
In MSI mode, the use of separate handlers and threads for the Intel
IPC, stream and SoundWire shared interrupt leads to timeouts and lost
interrupts.
The solution is to merge all interrupt handling across all links with
a single thread function. The use of a linked list enables this thread
function to walk through all contexts and figure out which link needs
attention.
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20191212014507.28050-9-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The existing use of 6 handlers is problematic in MSI mode. Update
headers so that all shared interrupts can be handled with a single
handler.
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20191212014507.28050-8-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The SoundWire DAIs for Intel platform are created in
drivers/soundwire/intel.c, while the communication with the Intel DSP
is all controlled in soc/sof/intel
When the DAI status changes, a callback is used to bridge the gap
between the two subsystems.
The naming of the existing 'config_stream' callback does not map well
with any of ALSA/ASoC concepts. This patch renames it as
'params_stream' to be more self-explanatory.
A new 'free_stream' callback is added in case any resources allocated
in the 'params_stream' stage need to be released. In the SOF
implementation, this is used in the hw_free case to release the DMA
channels over IPC.
These two callbacks now rely on structures which expose the link_id
and alh_stream_id (required by the firmware IPC), instead of a list of
parameters. The 'void *' definitions are changed to use explicit
types, as suggested on alsa-devel during earlier reviews.
Signed-off-by: Rander Wang <rander.wang@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20191212014507.28050-7-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The current interfaces between ASoC and SoundWire are limited by the
platform_device infrastructure to an init() and exit() (mapped to the
platform driver.probe and .remove)
To help with the platform detection, machine driver selection and
management of power dependencies between DSP and SoundWire IP, the
ASoC side requires:
a) an ACPI scan helper, to report if any devices are exposed in the
DSDT tables, and if any links are disabled by the BIOS.
b) a probe helper that allocates the resources without actually
starting the bus.
c) a startup helper which does start the bus when all power
dependencies are settled.
d) an exit helper to free all resources
e) an interrupt_enable/disable helper, typically invoked after the
startup helper but also used in suspend routines.
This patch moves all required interfaces to sdw_intel.h, mainly to
allow SoundWire and ASoC parts to be merged separately once the header
files are shared between trees.
To avoid compilation issues, the conflicts in intel_init.c are blindly
removed. This would in theory prevent the code from working, but since
there are no users of the Intel Soundwire driver this has no
impact. Functionality will be restored when the removal of platform
devices is complete.
Support for SoundWire + SOF builds will only be provided once all the
required pieces are upstream.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20191212014507.28050-6-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The Slave device initialization can be split in 4 different cases:
1. Master-initiated hardware reset, system suspend-resume and
pm_runtime based on clock-stop mode1. To avoid timeouts and a bad
audio experience, the Slave device resume operations need to wait for
the Slave device to be re-enumerated and its settings restored.
2. Exit from clock-stop mode0. In this case, the Slave device is
required to remain enumerated and its context preserved while the
clock is stopped, so no re-initialization or wait_for_completion() is
necessary.
3. Slave-initiated pm_runtime D3 transition. With the parent child
relationship, it is possible that a Slave device becomes 'suspended'
while its parent is still 'active' with the bus clock still
toggling. In this case, during the pm_runtime resume operation, there
is no need to wait for any settings to be restored.
4. Slave reset (sync loss or implementation-defined). In that case the
bus remains operational and the Slave device will be re-initialized
when it becomes ATTACHED again.
In previous patches, we suggested the use of wait_for_completion() to
deal with the case #1, but case #2 and #3 do not need any wait.
To account for those differences, this patch adds an unattach_request
field. The field is explicitly set by the Master for the case #1, and
if non-zero the Slave device shall wait on resume. In all other cases,
the Slave resume operations can proceed without wait.
The only request tracked so far is Master HardReset, but the request
is declared as a bit mask for future extensions (if needed). The
definition for this value is added in bus.h and does not need to be
exposed in sdw.h
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20191212014507.28050-5-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Slave drivers may have different ways of handling their settings, with
or without regmap.
During the integration of codec drivers, done in partnership between
Intel and Realtek, it became desirable to implement a predictable
order between low-level initializations performed in .update_status()
(invoked by an interrupt thread) and the settings restored in the
resume steps (invoked by the PM core).
This patch builds on the previous solution to wait for the Slave
device to be fully enumerated. The complete() in this case is signaled
not before the .update_status() is called, but after .update_status()
returns. Without this patch, the settings were not properly restored,
leading to timing-dependent 'no sound after resume' or 'no headset
detected after resume' bug reports.
Depending on how initialization is handled, a Slave device driver may
wait for enumeration_complete, or for initialization_complete, both
are valid synchronization points. They are initialized at the same
time, they only differ on when complete() is invoked.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20191212014507.28050-4-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
When the Master starts the bus (be it during the initial boot or
system resume), it usually performs a HardReset to make sure
electrical levels are correct, then enables the control channel.
While the PM framework guarantees that the Slave devices will only
become 'active' once the Master completes the bus initialization,
there is still a risk of a race condition: the Slave enumeration is
handled in a separate interrupt thread triggered by hardware status
changes, so the Slave device may not be ready to accept commands when
the Slave driver tries to access the registers and restore settings in
its resume or pm_runtime_resume callbacks. In those cases, any
read/write commands from/to the Slave device will result in a timeout.
This patch adds an enumeration_complete structure. When the bus is
goes through a HardReset sequence and restarted, the Slave will be
marked as UNATTACHED, which will result in a call to
init_completion().
When the Slave reports its presence during PING frames as a non-zero
Device, the Master hardware will issue an interrupt and the bus driver
will invoke complete(). The order between init_completion()/complete()
is predictable since this is a Master-initiated transition.
The Slave driver may use wait_for_completion() in its resume callback.
When regmap is used, the Slave driver will typically set its regmap in
cache-only mode on suspend, then on resume block on
wait_for_completion(&enumeration_complete) to guarantee it is safe to
start read/write transactions. It may then exit the cache-only mode
and use a regmap_sync to restore settings. All these steps are
optional, their use completely depends on the Slave device
capabilities and how the Slave driver is implemented.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20191212014507.28050-3-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
When a Slave device becomes synchronized with the bus, it may report
its presence in PING frames, as well as optionally asserting an
in-band PREQ signal.
The bus driver will detect a new Device0, start the enumeration
process and assign it a non-zero device number. The SoundWire
enumeration provides an arbitration to deal with multiple Slaves
reporting ATTACHED at the same time. The bus driver will also invoke
the driver .probe() callback associated with this device. The probe()
depends on the Linux device core, which handles the match operations
and may result in modules being loaded.
Once the non-zero device number is programmed, the Slave will report
its new status in PING frames and the Master hardware will typically
report this status change with an interrupt. At this point, the
.update_status() callback of the codec driver will be invoked (usually
from an interrupt thread or workqueue scheduled from the interrupt
thread).
The first race condition which can happen is between the .probe(),
which allocates the resources, and .update_status() where
initializations are typically handled. The .probe() is only called
once during the initial boot, while .update_status() will be called
for every bus hardware reset and if the Slave device loses
synchronization (an unlikely event but with non-zero probability).
The time difference between the end of the enumeration process and a
change of status reported by the hardware may be as small as one
SoundWire PING frame. The scheduling of the interrupt thread, which
invokes .update_status() is not deterministic, but can be small enough
to create a race condition. With a 48 kHz frame rate and ideal
scheduling cases, the .probe() may be pre-empted within double-digit
microseconds.
Since there is no guarantee that the .probe() completes by the time
.update_status() is invoked as a result of an interrupt, it's not
unusual for the .update_status() to rely on data structures that have
not been allocated yet, leading to kernel oopses.
This patch adds a probe_complete utility, which is used in the
sdw_update_slave_status() routine. The codec driver does not need to
do anything and can safely assume all resources are allocated in its
update_status() callback.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20191212014507.28050-2-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
There is no good reason why the unique_id needs to be stored as 4
bits. The code will work without changes with a u8 since all values
are already filtered while parsing the ACPI tables and Slave devID
registers.
Use u8 representation. This will allow us to encode a
"IGNORE_UNIQUE_ID" value to account for firmware/BIOS creativity.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20191022234808.17432-2-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
There is no reason to reserve a range of DAI IDs for SoundWire. This
is not scalable and it's better to let the ASoC core allocate the
dai->id when registering a component.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20190916192348.467-3-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
On most hardware platforms, SoundWire interfaces are pin-muxed with
other interfaces (typically DMIC or I2S) and the status of each link
needs to be checked at boot time.
For Intel platforms, the BIOS provides a menu to enable/disable the
links separately, and the information is provided to the OS with an
Intel-specific _DSD property. The same capability will be added to
revisions of the MIPI DisCo specification.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20190821185821.12690-5-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Add base debugfs mechanism for SoundWire bus by creating soundwire
root and master-N and slave-x hierarchy.
Also add SDW Slave SCP, DP0 and DP-N register debug file.
Registers not implemented will print as "XX"
Credits: this patch is based on an earlier internal contribution by
Vinod Koul, Sanyog Kale, Shreyas Nc and Hardik Shah.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Sanyog Kale <sanyog.r.kale@intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20190821185821.12690-2-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
To help pass platform-specific values, add a new field that can either
be set by the Master driver or read from firmware (BIOS/DT).
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20190806005522.22642-11-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
When integrating SoundWire, kbuild throws this warning with randconfig:
>> include/linux/soundwire/sdw.h:571:17: warning: 'struct
sdw_device_id' declared inside parameter list will not be visible
outside of this definition or declaration
const struct sdw_device_id *id);
^~~~~~~~~~~~~
Fix by adding the relevant include
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Bard liao <yung-chuan.liao@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20190806005522.22642-8-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>