From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:49:45 +0200 Subject: Adding upstream version 6.1.76. Signed-off-by: Daniel Baumann --- .../media/mediactl/media-ioc-device-info.rst | 106 +++++++++++++++++++++ 1 file changed, 106 insertions(+) create mode 100644 Documentation/userspace-api/media/mediactl/media-ioc-device-info.rst (limited to 'Documentation/userspace-api/media/mediactl/media-ioc-device-info.rst') diff --git a/Documentation/userspace-api/media/mediactl/media-ioc-device-info.rst b/Documentation/userspace-api/media/mediactl/media-ioc-device-info.rst new file mode 100644 index 000000000..d56ee6669 --- /dev/null +++ b/Documentation/userspace-api/media/mediactl/media-ioc-device-info.rst @@ -0,0 +1,106 @@ +.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later +.. c:namespace:: MC + +.. _media_ioc_device_info: + +*************************** +ioctl MEDIA_IOC_DEVICE_INFO +*************************** + +Name +==== + +MEDIA_IOC_DEVICE_INFO - Query device information + +Synopsis +======== + +.. c:macro:: MEDIA_IOC_DEVICE_INFO + +``int ioctl(int fd, MEDIA_IOC_DEVICE_INFO, struct media_device_info *argp)`` + +Arguments +========= + +``fd`` + File descriptor returned by :c:func:`open()`. + +``argp`` + Pointer to struct :c:type:`media_device_info`. + +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{8.5cm}| + +.. 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