Commit bc81c1c7 authored by Shuah Khan's avatar Shuah Khan Committed by Mauro Carvalho Chehab
Browse files

media: selftests: media_dev_allocator api test 



Add a new test for Media Device Allocator API.

Media Device Allocator API to allows multiple drivers share a media device.
This API solves a very common use-case for media devices where one physical
device (an USB stick) provides both audio and video. When such media device
exposes a standard USB Audio class, a proprietary Video class, two or more
independent drivers will share a single physical USB bridge. In such cases,
it is necessary to coordinate access to the shared resource.

Using this API, drivers can allocate a media device with the shared struct
device as the key. Once the media device is allocated by a driver, other
drivers can get a reference to it. The media device is released when all
the references are released.

This test does a series of unbind/bind tests to make sure media device
is released correctly when it is no longer is use and when the last
driver releases the reference.

Signed-off-by: default avatarShuah Khan <shuah@kernel.org>
Signed-off-by: default avatarHans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+samsung@kernel.org>
parent 383b0e5b

tools/testing/selftests/media_tests/media_dev_allocator.sh

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#!/bin/bash

# SPDX-License-Identifier: GPL-2.0

# Media Device Allocator API test script

# Copyright (c) 2019 Shuah Khan <shuah@kernel.org>



echo "Media Device Allocator testing: unbind and bind"

echo "media driver $1 audio driver $2"



MDRIVER=/sys/bus/usb/drivers/$1

cd $MDRIVER

MDEV=$(ls -d *\-*)



ADRIVER=/sys/bus/usb/drivers/$2

cd $ADRIVER

ADEV=$(ls -d *\-*.1)



echo "=================================="

echo "Test unbind both devices - start"

echo "Running unbind of $MDEV from $MDRIVER"

echo $MDEV > $MDRIVER/unbind;



echo "Media device should still be present!"

ls -l /dev/media*



echo "sound driver is at: $ADRIVER"

echo "Device is: $ADEV"



echo "Running unbind of $ADEV from $ADRIVER"

echo $ADEV > $ADRIVER/unbind;



echo "Media device should have been deleted!"

ls -l /dev/media*

echo "Test unbind both devices - end"



echo "=================================="



echo "Test bind both devices - start"

echo "Running bind of $MDEV from $MDRIVER"

echo $MDEV > $MDRIVER/bind;



echo "Media device should be present!"

ls -l /dev/media*



echo "Running bind of $ADEV from $ADRIVER"

echo $ADEV > $ADRIVER/bind;



echo "Media device should be there!"

ls -l /dev/media*



echo "Test bind both devices - end"



echo "=================================="



echo "Test unbind $MDEV - bind $MDEV - unbind $ADEV - bind $ADEV start"



echo "Running unbind of $MDEV from $MDRIVER"

echo $MDEV > $MDRIVER/unbind;



echo "Media device should be there!"

ls -l /dev/media*



sleep 1



echo "Running bind of $MDEV from $MDRIVER"

echo $MDEV > $MDRIVER/bind;



echo "Media device should be there!"

ls -l /dev/media*



echo "Running unbind of $ADEV from $ADRIVER"

echo $ADEV > $ADRIVER/unbind;



echo "Media device should be there!"

ls -l /dev/media*



sleep 1



echo "Running bind of $ADEV from $ADRIVER"

echo $ADEV > $ADRIVER/bind;



echo "Media device should be there!"

ls -l /dev/media*



echo "Test unbind $MDEV - bind $MDEV - unbind $ADEV - bind $ADEV end"

echo "=================================="

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