linux/drivers/soundwire
Srinivas Kandagatla ddea6cf7b6 soundwire: qcom: update register read/write routine
In the existing code every soundwire register read and register write
are kinda blocked. Each of these are using a special command id that
generates interrupt after it successfully finishes. This is really
overhead, limiting and not really necessary unless we are doing
something special.

We can simply read/write the fifo that should also give exactly
what we need! This will also allow to read/write registers in
interrupt context, which was not possible with the special
command approach.

With previous approach number of interrupts generated
after enumeration are around 130:
$ cat /proc/interrupts  | grep soundwire
 21: 130 0 0 0 0 0 0 0 GICv3 234 Edge      soundwire

after this patch they are just 3 interrupts
$ cat /proc/interrupts  | grep soundwire
 21: 3 0 0 0 0 0 0 0 GICv3 234 Edge      soundwire

This has significantly not only reduced interrupting CPU during enumeration
but also during streaming!

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20210330144719.13284-6-srinivas.kandagatla@linaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2021-03-30 22:55:07 +05:30
..
bus_type.c soundwire: bus: use correct driver name in error messages 2021-03-30 11:51:42 +05:30
bus.c soundwire: bus: Fix device found flag correctly 2021-03-30 12:30:01 +05:30
bus.h soundwire: Intel: introduce DMI quirks for HP Spectre x360 Convertible 2021-03-22 17:33:10 +05:30
cadence_master.c soundwire: cadence: only prepare attached devices on clock stop 2021-03-30 14:36:11 +05:30
cadence_master.h soundwire: cadence: fix race condition between suspend and Slave device alerts 2020-09-09 13:14:42 +05:30
debugfs.c soundwire: Revert "soundwire: debugfs: use controller id instead of link_id" 2021-02-06 15:52:21 +05:30
dmi-quirks.c soundwire: Intel: add DMI quirk for Dell SKU 0A3E 2021-03-22 17:33:10 +05:30
generic_bandwidth_allocation.c soundwire: generic_allocation: fix confusion between group and packing 2021-03-30 14:36:11 +05:30
intel_init.c ALSA: hda: move Intel SoundWire ACPI scan to dedicated module 2021-03-02 15:33:00 +01:00
intel.c soundwire: intel: remove useless readl 2021-03-30 11:51:43 +05:30
intel.h ALSA: hda: move Intel SoundWire ACPI scan to dedicated module 2021-03-02 15:33:00 +01:00
Kconfig soundwire: Add generic bandwidth allocation algorithm 2020-09-18 17:48:51 +05:30
Makefile soundwire: Intel: introduce DMI quirks for HP Spectre x360 Convertible 2021-03-22 17:33:10 +05:30
master.c soundwire: master: use pm_runtime_set_active() on add 2020-12-02 12:49:34 +05:30
mipi_disco.c soundwire: fix port_ready[] dynamic allocation in mipi_disco 2020-09-03 16:02:29 +05:30
qcom.c soundwire: qcom: update register read/write routine 2021-03-30 22:55:07 +05:30
slave.c soundwire: add override addr ops 2021-03-22 17:33:10 +05:30
stream.c soundwire: stream: remove useless bus initializations 2021-03-30 11:51:44 +05:30
sysfs_local.h soundwire: sysfs: add slave status and device number before probe 2020-09-28 11:17:43 +05:30
sysfs_slave_dpn.c soundwire: Fix DEBUG_LOCKS_WARN_ON for uninitialized attribute 2020-11-24 14:08:51 +05:30
sysfs_slave.c soundwire: sysfs: Constify static struct attribute_group 2021-01-19 20:21:20 +05:30