wireguard-linux/drivers/soundwire/bus.h, branch jd/unified-crypt-queue

soundwire: bus: add helper to clear Slave status to UNATTACHED

2020-02-25T10:27:02Z

When resuming with a bus reset, we need to re-enumerate and restart from UNATTACHED. The helper added in this patch helps implement a more robust state machine avoiding race conditions on resume. The unattach request is stored and will be used by Slave drivers, if needed: Intel validation exposed a corner case where the Slave device may transition to D3 when streaming stops, but streaming restarts before the Master transitions to D3. In that case, the Slave status was not cleared as UNATTACHED by the Master resuming, and the wait_for_completion will time out. When the slave resumes, it can check if a Master-initiated re-enumeration and initialization took place and skip the wait_for_completion() if there is no reason to wait. Signed-off-by: Pierre-Louis Bossart Link: https://lore.kernel.org/r/20200115000844.14695-7-pierre-louis.bossart@linux.intel.com Signed-off-by: Vinod Koul

soundwire: bus: fix race condition with probe_complete signaling

2020-02-25T10:27:01Z

The driver probe takes care of basic initialization and is invoked when a Slave becomes attached, after a match between the Slave DevID registers and ACPI/DT entries. The update_status callback is invoked when a Slave state changes, e.g. when it is assigned a non-zero Device Number and it reports with an ATTACHED/ALERT state. The state change detection is usually hardware-based and based on the SoundWire frame rate (e.g. double-digit microseconds) while the probe is a pure software operation, which may involve a kernel module load. In corner cases, it's possible that the state changes before the probe completes. This patch suggests the use of wait_for_completion to avoid races on startup, so that the update_status callback does not rely on invalid pointers/data structures. Signed-off-by: Rander Wang Signed-off-by: Pierre-Louis Bossart Link: https://lore.kernel.org/r/20200115000844.14695-2-pierre-louis.bossart@linux.intel.com Signed-off-by: Vinod Koul

soundwire: core: add device tree support for slave devices

2019-09-04T07:42:31Z

This patch adds support to parsing device tree based SoundWire slave devices. Signed-off-by: Srinivas Kandagatla Link: https://lore.kernel.org/r/20190829163514.11221-3-srinivas.kandagatla@linaro.org Signed-off-by: Vinod Koul

soundwire: add debugfs support

2019-08-23T06:31:02Z

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 Acked-by: Sanyog Kale Signed-off-by: Pierre-Louis Bossart Link: https://lore.kernel.org/r/20190821185821.12690-2-pierre-louis.bossart@linux.intel.com Signed-off-by: Vinod Koul

soundwire: export helpers to find row and column values

2019-08-21T09:06:01Z

Add a prefix for common tables and export 2 helpers to set the frame shapes based on row/col values. These changes simplify bandwidth allocation algorithms as well as the Cadence parts which all need to convert from frame shape to indices used by the standard. These helpers are used in the following patch. Signed-off-by: Pierre-Louis Bossart Link: https://lore.kernel.org/r/20190806005522.22642-6-pierre-louis.bossart@linux.intel.com Signed-off-by: Vinod Koul

soundwire: fix alignment issues in header files

2019-05-02T15:16:26Z

use Linux style Reviewed-by: Takashi Iwai Signed-off-by: Pierre-Louis Bossart Signed-off-by: Greg Kroah-Hartman

soundwire: fix SPDX license for header files

2019-05-02T15:09:00Z

No C++ comments in .h files Reviewed-by: Takashi Iwai Signed-off-by: Pierre-Louis Bossart Signed-off-by: Greg Kroah-Hartman

soundwire: Add support for multi link bank switch

2018-08-27T04:19:48Z

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 Signed-off-by: Shreyas NC Acked-by: Pierre-Louis Bossart Signed-off-by: Vinod Koul

soundwire: Add support to lock across bus instances

2018-08-27T04:19:48Z

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 Signed-off-by: Shreyas NC Acked-by: Pierre-Louis Bossart Signed-off-by: Vinod Koul

soundwire: Add bank switch routine

2018-05-11T16:17:05Z

SoundWire supports two registers banks. So, program the alternate bank with new configuration and then performs bank switch. Signed-off-by: Sanyog Kale Signed-off-by: Shreyas NC Signed-off-by: Vinod Koul