--- zzzz-none-000/linux-3.10.107/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml 2021-02-04 17:41:59.000000000 +0000 @@ -72,23 +72,30 @@ size and reserved2 fields of each &v4l2-ext-control; and call the VIDIOC_G_EXT_CTRLS ioctl. String controls controls -must also set the string field. +must also set the string field. Controls +of compound types (V4L2_CTRL_FLAG_HAS_PAYLOAD is set) +must set the ptr field. If the size is too small to receive the control result (only relevant for pointer-type controls like strings), then the driver will set size to a valid value and return an &ENOSPC;. You should re-allocate the -string memory to this new size and try again. It is possible that the -same issue occurs again if the string has grown in the meantime. It is +memory to this new size and try again. For the string type it is possible that +the same issue occurs again if the string has grown in the meantime. It is recommended to call &VIDIOC-QUERYCTRL; first and use maximum+1 as the new size value. It is guaranteed that that is sufficient memory. + N-dimensional arrays are set and retrieved row-by-row. You cannot set a partial +array, all elements have to be set or retrieved. The total size is calculated +as elems * elem_size. +These values can be obtained by calling &VIDIOC-QUERY-EXT-CTRL;. + To change the value of a set of controls applications initialize the id, size, reserved2 and -value/string fields of each &v4l2-ext-control; and +value/value64/string/ptr fields of each &v4l2-ext-control; and call the VIDIOC_S_EXT_CTRLS ioctl. The controls will only be set if all control values are valid. @@ -96,7 +103,7 @@ To check if a set of controls have correct values applications initialize the id, size, reserved2 and -value/string fields of each &v4l2-ext-control; and +value/value64/string/ptr fields of each &v4l2-ext-control; and call the VIDIOC_TRY_EXT_CTRLS ioctl. It is up to the driver whether wrong values are automatically adjusted to a valid value or if an error is returned. @@ -158,19 +165,54 @@ __s32 value - New value or current value. + New value or current value. Valid if this control is not of +type V4L2_CTRL_TYPE_INTEGER64 and +V4L2_CTRL_FLAG_HAS_PAYLOAD is not set. __s64 value64 - New value or current value. + New value or current value. Valid if this control is of +type V4L2_CTRL_TYPE_INTEGER64 and +V4L2_CTRL_FLAG_HAS_PAYLOAD is not set. char * string - A pointer to a string. + A pointer to a string. Valid if this control is of +type V4L2_CTRL_TYPE_STRING. + + + + __u8 * + p_u8 + A pointer to a matrix control of unsigned 8-bit values. +Valid if this control is of type V4L2_CTRL_TYPE_U8. + + + + __u16 * + p_u16 + A pointer to a matrix control of unsigned 16-bit values. +Valid if this control is of type V4L2_CTRL_TYPE_U16. + + + + __u32 * + p_u32 + A pointer to a matrix control of unsigned 32-bit values. +Valid if this control is of type V4L2_CTRL_TYPE_U32. + + + + void * + ptr + A pointer to a compound type which can be an N-dimensional array and/or a +compound type (the control's type is >= V4L2_CTRL_COMPOUND_TYPES). +Valid if V4L2_CTRL_FLAG_HAS_PAYLOAD is set for this control. + @@ -327,7 +369,12 @@ These controls are described in . - + + V4L2_CTRL_CLASS_RF_TUNER + 0xa20000 + The class containing RF tuner controls. +These controls are described in . +