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envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -28 X-Spam_score: -2.9 X-Spam_bar: -- X-Spam_report: (-2.9 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.845, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-arm@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-arm-bounces+alex.bennee=linaro.org@nongnu.org Sender: qemu-arm-bounces+alex.bennee=linaro.org@nongnu.org X-TUID: Nvpblh/IcyGU Nikita Shubin via B4 Relay writes: > From: Nikita Shubin > > Add GUSE (FUSE based kernel module similiar to CUSE) based backend. > > This allows transparent usage of Linux GPIO UAPI based tools like > in kernel tools/gpio or libgpiod. > > libgpiod requires some modification to allow "/sys/class/guse" in > gpiod_check_gpiochip_device(). > > It requires guse module to be loaded and providing DEVICE()->id > for GPIO module, for example: > > ``` > DEVICE(&s->gpio)->id = g_strdup("aspeed-gpio0"); > ``` > > The id should be provided to gpiodev with any `devname` that doesn't > exists in /dev: > > ``` > -gpiodev guse,id=aspeed-gpio0,devname=gpiochip10 > ``` > > That /dev/gpiochip10 can be used in the same way we usually operate with > gpiochip's. > > Link: http://git.maquefel.me/?p=qemu-gpiodev/libgpiod.git;a=shortlog;h=refs/heads/nshubin/guse-fix > Link: http://git.maquefel.me/?p=qemu-gpiodev/guse.git;a=summary > Link: http://git.maquefel.me/?p=qemu-gpiodev/libfuse.git;a=shortlog;h=refs/heads/nshubin/guse > Signed-off-by: Nikita Shubin [...] > diff --git a/qapi/gpio.json b/qapi/gpio.json > index 1c2b7af36813ff52cbb3a44e64a2e5a5d8658d62..e3cdca793260212622a30947eaea61bd523e98fb 100644 > --- a/qapi/gpio.json > +++ b/qapi/gpio.json > @@ -21,12 +21,36 @@ > ## > # @GpiodevBackendKind: > # > -# @chardev: chardevs > +# @chardev: Gpio dev over chardev backend > +# @gusedev: Gpio dev over GUSE FUSE module > # > # Since: 9.2 10.1 > ## > { 'enum': 'GpiodevBackendKind', > - 'data': [ 'chardev' ] } > + 'data': [ 'chardev', > + { 'name': 'gusedev', 'if': 'CONFIG_LINUX' } ] } > + > +## > +# @GpiodevGusedev: > +# > +# Configuration info for guse gpiodevs. > +# > +# @devname: Name of device created in /dev Existing names for similar things elsewhere: * @dev in AudiodevAlsaPerDirectionOptions * @device in ChardevHostdev * @devname in NetdevNetmapOptions * @vhostdev in NetdevVhostUserOptions * @sev-device in SevCommonProperties * @filename in RngRandomProperties * @path in BlockdevOptionsNvmeIoUring, BlockdevOptionsVirtioBlkVhostVdpa, TPMPassthroughOptions What a mess. @filename and @path are clearly bad. I'd prefer @device or @gpio-device, or maybe @dev. > +# > +# Since: 9.2 > +## > + { 'struct': 'GpiodevGusedev', > + 'data': { 'devname': 'str' } } > + > +## > +# @GpiodevGusedevWrapper: > +# > +# @data: Configuration info for chardev gpiodevs > +# > +# Since: 9.2 > +## > +{ 'struct': 'GpiodevGusedevWrapper', > + 'data': { 'data': 'GpiodevGusedev' } } Avoid the wrapper? > > ## > # @GpiodevChardev: > @@ -65,4 +89,5 @@ > { 'union': 'GpiodevBackend', > 'base': { 'type': 'GpiodevBackendKind' }, > 'discriminator': 'type', > - 'data': { 'chardev': 'GpiodevChardevWrapper' } } > \ No newline at end of file > + 'data': { 'chardev': 'GpiodevChardevWrapper', > + 'gusedev': { 'type': 'GpiodevGusedevWrapper', 'if': 'CONFIG_LINUX' } } } > \ No newline at end of file Please add a newline at the end of the file.