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| author | Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> | 2020-09-24 14:44:30 -0500 |
|---|---|---|
| committer | Vinod Koul <vkoul@kernel.org> | 2020-09-28 11:17:43 +0530 |
| commit | 0173f525b2c1b02a51784e2119d434593235aed1 (patch) | |
| tree | be7fd015e55158bb0ce939863460626788948415 /Documentation/ABI | |
| parent | fcb9d730be1d3010e0c8fdc5aaff62836d7a942c (diff) | |
| download | linux-0173f525b2c1b02a51784e2119d434593235aed1.tar.bz2 | |
soundwire: sysfs: add slave status and device number before probe
The MIPI DisCo device properties that are read by the driver from
platform firmware, or hard-coded in the driver, should only be
provided as sysfs entries when a driver probes successfully.
However the device status and device number is updated even when there
is no driver present, and hence can be updated when a Slave device is
detected on the bus without being described in platform firmware and
without any driver registered/probed.
As suggested by GregKH, the attribute group for Slave status and
device number is is added by default upon device registration.
Credits to Vinod Koul for the status_show() function, shared in a
separate patch and used as is here. The status table was modified to
remove an unnecessary enum and status_show() is handled in a different
group attribute than what was suggested by Vinod.
Tested-by: Srinivas Kandgatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Co-developed-by: Vinod Koul <vkoul@kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20200924194430.121058-3-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'Documentation/ABI')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-bus-soundwire-slave | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-soundwire-slave b/Documentation/ABI/testing/sysfs-bus-soundwire-slave index db4c9511d1aa..d324aa0b678f 100644 --- a/Documentation/ABI/testing/sysfs-bus-soundwire-slave +++ b/Documentation/ABI/testing/sysfs-bus-soundwire-slave @@ -1,3 +1,21 @@ +What: /sys/bus/soundwire/devices/sdw:.../status + /sys/bus/soundwire/devices/sdw:.../device_number + +Date: September 2020 + +Contact: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> + Bard Liao <yung-chuan.liao@linux.intel.com> + Vinod Koul <vkoul@kernel.org> + +Description: SoundWire Slave status + + These properties report the Slave status, e.g. if it + is UNATTACHED or not, and in the latter case show the + device_number. This status information is useful to + detect devices exposed by platform firmware but not + physically present on the bus, and conversely devices + not exposed in platform firmware but enumerated. + What: /sys/bus/soundwire/devices/sdw:.../dev-properties/mipi_revision /sys/bus/soundwire/devices/sdw:.../dev-properties/wake_capable /sys/bus/soundwire/devices/sdw:.../dev-properties/test_mode_capable |