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
211       - The control class to which all controls belong, see
213 	handling controls will also accept a value of 0 here, meaning that
214 	the controls can belong to any control class. Whether drivers
224 	these controls have to be retrieved from a request or tried/set for
235 	(see :ref:`ctrl-class`). In that case all controls have to
247       - The number of controls in the controls array. May also be zero.
257 	Before controls are read from/written to hardware a validation
258 	step takes place: this checks if all controls in the list are
259 	valid controls, if no attempt is made to write to a read-only
279 	``error_idx`` is less than ``count`` and only the controls up to
281 	the remaining controls is undefined.
304       - ``controls``
320       - The class containing user controls. These controls are described
321 	in :ref:`control`. All controls that can be set using the
327       - The class containing MPEG compression controls. These controls are
328 	described in :ref:`mpeg-controls`.
331       - The class containing camera controls. These controls are described
332 	in :ref:`camera-controls`.
335       - The class containing FM Transmitter (FM TX) controls. These
336 	controls are described in :ref:`fm-tx-controls`.
339       - The class containing flash device controls. These controls are
340 	described in :ref:`flash-controls`.
343       - The class containing JPEG compression controls. These controls are
344 	described in :ref:`jpeg-controls`.
347       - The class containing image source controls. These controls are
348 	described in :ref:`image-source-controls`.
351       - The class containing image processing controls. These controls are
352 	described in :ref:`image-process-controls`.
355       - The class containing FM Receiver (FM RX) controls. These controls
356 	are described in :ref:`fm-rx-controls`.
359       - The class containing RF tuner controls. These controls are
360 	described in :ref:`rf-tuner-controls`.