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+.. -*- coding: utf-8; mode: rst -*-
+
+.. _media_ioc_device_info:
+
+***************************
+ioctl MEDIA_IOC_DEVICE_INFO
+***************************
+
+Name
+====
+
+MEDIA_IOC_DEVICE_INFO - Query device information
+
+
+Synopsis
+========
+
+.. cpp:function:: int ioctl( int fd, int request, struct media_device_info *argp )
+
+
+Arguments
+=========
+
+``fd``
+    File descriptor returned by :ref:`open() <media-func-open>`.
+
+``request``
+    MEDIA_IOC_DEVICE_INFO
+
+``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 :ref:`media_device_info <media-device-info>`. The driver
+fills the structure and returns the information to the application. The
+ioctl never fails.
+
+
+.. _media-device-info:
+
+.. flat-table:: struct media_device_info
+    :header-rows:  0
+    :stub-columns: 0
+    :widths:       1 1 2
+
+
+    -  .. row 1
+
+       -  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.
+
+    -  .. row 2
+
+       -  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.
+
+    -  .. row 3
+
+       -  char
+
+       -  ``serial``\ [40]
+
+       -  Serial number as a NUL-terminated ASCII string.
+
+    -  .. row 4
+
+       -  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.
+
+    -  .. row 5
+
+       -  __u32
+
+       -  ``media_version``
+
+       -  Media API version, formatted with the ``KERNEL_VERSION()`` macro.
+
+    -  .. row 6
+
+       -  __u32
+
+       -  ``hw_revision``
+
+       -  Hardware device revision in a driver-specific format.
+
+    -  .. row 7
+
+       -  __u32
+
+       -  ``driver_version``
+
+       -  Media device driver version, formatted with the
+	  ``KERNEL_VERSION()`` macro. Together with the ``driver`` field
+	  this identifies a particular driver.
+
+    -  .. row 8
+
+       -  __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 <gen-errors>` chapter.