From 76cb841cb886eef6b3bee341a2266c76578724ad Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Mon, 6 May 2024 03:02:30 +0200 Subject: Adding upstream version 4.19.249. Signed-off-by: Daniel Baumann --- .../media/uapi/mediactl/media-ioc-device-info.rst | 110 +++++++++++++++++++++ 1 file changed, 110 insertions(+) create mode 100644 Documentation/media/uapi/mediactl/media-ioc-device-info.rst (limited to 'Documentation/media/uapi/mediactl/media-ioc-device-info.rst') diff --git a/Documentation/media/uapi/mediactl/media-ioc-device-info.rst b/Documentation/media/uapi/mediactl/media-ioc-device-info.rst new file mode 100644 index 000000000..649cb3d9e --- /dev/null +++ b/Documentation/media/uapi/mediactl/media-ioc-device-info.rst @@ -0,0 +1,110 @@ +.. -*- coding: utf-8; mode: rst -*- + +.. _media_ioc_device_info: + +*************************** +ioctl MEDIA_IOC_DEVICE_INFO +*************************** + +Name +==== + +MEDIA_IOC_DEVICE_INFO - Query device information + + +Synopsis +======== + +.. c:function:: int ioctl( int fd, MEDIA_IOC_DEVICE_INFO, struct media_device_info *argp ) + :name: MEDIA_IOC_DEVICE_INFO + + +Arguments +========= + +``fd`` + File descriptor returned by :ref:`open() `. + +``argp`` + + +Description +=========== + +All media devices must support the ``MEDIA_IOC_DEVICE_INFO`` ioctl. To +query device information, applications call the ioctl with a pointer to +a struct :c:type:`media_device_info`. The driver +fills the structure and returns the information to the application. The +ioctl never fails. + + +.. c:type:: media_device_info + +.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.7cm}| + +.. flat-table:: struct media_device_info + :header-rows: 0 + :stub-columns: 0 + :widths: 1 1 2 + + + * - char + - ``driver``\ [16] + - Name of the driver implementing the media API as a NUL-terminated + ASCII string. The driver version is stored in the + ``driver_version`` field. + + Driver specific applications can use this information to verify + the driver identity. It is also useful to work around known bugs, + or to identify drivers in error reports. + + * - char + - ``model``\ [32] + - Device model name as a NUL-terminated UTF-8 string. The device + version is stored in the ``device_version`` field and is not be + appended to the model name. + + * - char + - ``serial``\ [40] + - Serial number as a NUL-terminated ASCII string. + + * - char + - ``bus_info``\ [32] + - Location of the device in the system as a NUL-terminated ASCII + string. This includes the bus type name (PCI, USB, ...) and a + bus-specific identifier. + + * - __u32 + - ``media_version`` + - Media API version, formatted with the ``KERNEL_VERSION()`` macro. + + * - __u32 + - ``hw_revision`` + - Hardware device revision in a driver-specific format. + + * - __u32 + - ``driver_version`` + - Media device driver version, formatted with the + ``KERNEL_VERSION()`` macro. Together with the ``driver`` field + this identifies a particular driver. + + * - __u32 + - ``reserved``\ [31] + - Reserved for future extensions. Drivers and applications must set + this array to zero. + + +The ``serial`` and ``bus_info`` fields can be used to distinguish +between multiple instances of otherwise identical hardware. The serial +number takes precedence when provided and can be assumed to be unique. +If the serial number is an empty string, the ``bus_info`` field can be +used instead. The ``bus_info`` field is guaranteed to be unique, but can +vary across reboots or device unplug/replug. + + +Return Value +============ + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes ` chapter. -- cgit v1.2.3