media/v4l/vidioc-g-ext-ctrls.rst

13 …OC_S_EXT_CTRLS - VIDIOC_TRY_EXT_CTRLS - Get or set the value of several controls, try control valu…
42 These ioctls allow the caller to get or set multiple controls
44 :ref:`ctrl-class`) and all controls in the control array must belong
47 Applications must always fill in the ``count``, ``which``, ``controls``
51 by the ``controls`` fields.
53 To get the current value of a set of controls applications initialize
56 :ref:`VIDIOC_G_EXT_CTRLS <VIDIOC_G_EXT_CTRLS>` ioctl. String controls controls must also set the
57 ``string`` field. Controls of compound types
61 relevant for pointer-type controls like strings), then the driver will
75 To change the value of a set of controls applications initialize the
78 the :ref:`VIDIOC_S_EXT_CTRLS <VIDIOC_G_EXT_CTRLS>` ioctl. The controls will only be set if *all*
81 To check if a set of controls have correct values applications
99 then the controls are not applied immediately when calling
112 values of the controls at the time of request completion.
116 The driver will only set/get these controls if all control values are
117 correct. This prevents the situation where only some of the controls
138 	normally 0, but for pointer controls this should be set to the
147 	   For string controls, this ``size`` field should
219       - The control class to which all controls belong, see
221 	handling controls will also accept a value of 0 here, meaning that
222 	the controls can belong to any control class. Whether drivers
232 	these controls have to be retrieved from a request or tried/set for
243 	(see :ref:`ctrl-class`). In that case all controls have to
255       - The number of controls in the controls array. May also be zero.
265 	Before controls are read from/written to hardware a validation
266 	step takes place: this checks if all controls in the list are
267 	valid controls, if no attempt is made to write to a read-only
287 	``error_idx`` is less than ``count`` and only the controls up to
289 	the remaining controls is undefined.
312       - ``controls``
328       - The class containing user controls. These controls are described
329 	in :ref:`control`. All controls that can be set using the
335       - The class containing MPEG compression controls. These controls are
336 	described in :ref:`mpeg-controls`.
339       - The class containing camera controls. These controls are described
340 	in :ref:`camera-controls`.
343       - The class containing FM Transmitter (FM TX) controls. These
344 	controls are described in :ref:`fm-tx-controls`.
347       - The class containing flash device controls. These controls are
348 	described in :ref:`flash-controls`.
351       - The class containing JPEG compression controls. These controls are
352 	described in :ref:`jpeg-controls`.
355       - The class containing image source controls. These controls are
356 	described in :ref:`image-source-controls`.
359       - The class containing image processing controls. These controls are
360 	described in :ref:`image-process-controls`.
363       - The class containing FM Receiver (FM RX) controls. These controls
364 	are described in :ref:`fm-rx-controls`.
367       - The class containing RF tuner controls. These controls are
368 	described in :ref:`rf-tuner-controls`.
371       - The class containing colorimetry controls. These controls are
372         described in :ref:`colorimetry-controls`.