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>
The existing definitions are ambiguous and possibly misleading.
For DP0, 'flow-control' is only relevant for the BRA protocol and
should not be confused with async modes explicitly not supported for
DP0, add prefix to follow MIPI DisCo definition
The use of 'device_interrupts' is also questionable. The MIPI
SoundWire spec defines Slave-, DP0- and DPN-level
implementation-defined interrupts. Using the 'device' prefix in the
last two cases is misleading, not only is the term 'device' overloaded
but these properties are only valid at the DP0 and DPn levels. Rename
to follow the MIPI definitions, no need to be creative here.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The MIPI DisCo spec refers to dynamic frame shape, not to dynamic
shape. Clarify.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Fix support for clock_stop_mode0 and 1. The existing code uses a
bitmask between enums, one of which being zero. Or-ing with zero is
not very useful in general...Fix by or-ing with a BIT dependent on the
enum value.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Rename all fields with 'freq' as 'clk_freq' to follow the MIPI
specification and avoid confusion between bus clock and audio clocks.
No functionality change.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The master_count is only defined for a Controller or a Slave in the
MIPI DisCo for SoundWire document.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The SoundWire and DisCo specifications do not define Master data ports
or related properties. Data ports are only defined for Slave devices,
so remove the unused member in properties.
Credits: this patch is based on an earlier internal contribution by
Vinod Koul, Sanyog Kale, Shreyas Nc and Hardik Shah.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Somehow previous header files did not include definition for
sink/source, flow and grouping.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
macro argument should be inside a parenthesis to avoid precedence
issues
checkpatch complains:
CHECK: Macro argument 'n' may be better as '(n)' to avoid
precedence issues
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Found few more issues reported checkpatch on code alignment so fix those
as well in the soundwire core.
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some more headers had C++ style SDPX line, fix that and change copyright
so that it is consistent with rest of the code in subsystem
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A multi link bankswitch can be done if the hardware supports and
the stream is handled by multiple Master(s).
This preparatory patch adds support to track m_rt in a stream.
Modifying m_rt_count and usage is added as part of the next patch.
Signed-off-by: Shreyas NC <shreyas.nc@intel.com>
Acked-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
In cases of multiple Masters in a stream, synchronization
between multiple Master(s) is achieved by performing bank switch
together and using Master methods.
Add sdw_ml_bank_switch() to wait for completion of bank switch.
Signed-off-by: Sanyog Kale <sanyog.r.kale@intel.com>
Signed-off-by: Shreyas NC <shreyas.nc@intel.com>
Acked-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
For each SoundWire stream operation, we need to parse master
list and operate upon all master runtime.
This is a preparatory patch to do the boilerplate conversion
of stream handling from single master runtime to handle a
list of master runtime. The code to support bank switch for
multiple master instances is added in the next patch.
Signed-off-by: Sanyog Kale <sanyog.r.kale@intel.com>
Signed-off-by: Shreyas NC <shreyas.nc@intel.com>
Acked-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Currently, the stream concept is limited to single Master and one
or more Codecs.
This patch extends the concept to support multiple Master(s)
sharing the same reference clock and synchronized in the hardware.
Modify sdw_stream_runtime to support a list of sdw_master_runtime
for the same. The existing reference to a single m_rt is removed
in the next patch.
Typically to lock, one would acquire a global lock and then lock
bus instances. In this case, the caller framework(ASoC DPCM)
guarantees that stream operations on a card are always serialized.
So, there is no race condition and hence no need for global lock.
Bus lock(s) are acquired to reconfigure the bus while the stream
is set-up.
So, we add sdw_acquire_bus_lock()/sdw_release_bus_lock() APIs which
are used only to reconfigure the bus.
Signed-off-by: Sanyog Kale <sanyog.r.kale@intel.com>
Signed-off-by: Shreyas NC <shreyas.nc@intel.com>
Acked-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Add DAI registration and DAI ops for the Intel driver along with
callback for topology configuration.
Signed-off-by: Sanyog Kale <sanyog.r.kale@intel.com>
Signed-off-by: Shreyas NC <shreyas.nc@intel.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
SoundWire supports two registers banks. So, program the alternate bank
with new configuration and then performs bank switch.
Signed-off-by: Sanyog Kale <sanyog.r.kale@intel.com>
Signed-off-by: Shreyas NC <shreyas.nc@intel.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Master and Slave port registers need to be programmed for each port
used in a stream. Add the helpers for port register programming.
Signed-off-by: Sanyog Kale <sanyog.r.kale@intel.com>
Signed-off-by: Shreyas NC <shreyas.nc@intel.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Add Soundwire port data structures and APIS for initialization
and release of ports.
Signed-off-by: Sanyog Kale <sanyog.r.kale@intel.com>
Signed-off-by: Shreyas NC <shreyas.nc@intel.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
This patch adds APIs and relevant stream data structures
for initialization and release of stream.
Signed-off-by: Hardik T Shah <hardik.t.shah@intel.com>
Signed-off-by: Sanyog Kale <sanyog.r.kale@intel.com>
Signed-off-by: Shreyas NC <shreyas.nc@intel.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Add status handling API sdw_handle_slave_status() to handle
Slave status changes.
Signed-off-by: Hardik T Shah <hardik.t.shah@intel.com>
Signed-off-by: Sanyog Kale <sanyog.r.kale@intel.com>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Acked-By: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
SoundWire Slaves report status to bus. Add helpers to handle
the status changes.
Signed-off-by: Hardik T Shah <hardik.t.shah@intel.com>
Signed-off-by: Sanyog Kale <sanyog.r.kale@intel.com>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Acked-By: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
SoundWire bus supports read or write register(s) for SoundWire Slave
device. sdw_read() and sdw_write() APIs are provided for single
register read/write. sdw_nread() and sdw_nwrite() for operations on
contiguous registers.
Signed-off-by: Sanyog Kale <sanyog.r.kale@intel.com>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Acked-By: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
MIPI Discovery And Configuration (DisCo) Specification for SoundWire
specifies properties to be implemented for SoundWire Masters and
Slaves. The DisCo spec doesn't mandate these properties. However,
SDW bus cannot work without knowing these values.
The helper functions read the Master and Slave properties.
Implementers of Master or Slave drivers can use any of the below
three mechanisms:
a) Use these APIs here as .read_prop() callback for Master
and Slave
b) Implement own methods and set those as .read_prop(), but invoke
APIs in this file for generic read and override the values with
platform specific data
c) Implement ones own methods which do not use anything provided
here
Signed-off-by: Sanyog Kale <sanyog.r.kale@intel.com>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Acked-By: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A Master adds a SoundWire bus instance which scans the firmware
provided for device description.
In this patch we scan ACPI namespaces and create SoundWire
Slave devices based on ACPI description
Signed-off-by: Sanyog Kale <sanyog.r.kale@intel.com>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Acked-By: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This adds the base SoundWire bus type, bus and driver registration.
along with changes to module device table for new SoundWire
device type.
Signed-off-by: Sanyog Kale <sanyog.r.kale@intel.com>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Acked-By: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
