0001
0002 - The Frame Interval Monitor could be exported to v4l2-core for
0003 general use.
0004
0005 - The CSI subdevice parses its nearest upstream neighbor's device-tree
0006 bus config in order to setup the CSI. Laurent Pinchart argues that
0007 instead the CSI subdev should call its neighbor's g_mbus_config op
0008 (which should be propagated if necessary) to get this info. However
0009 Hans Verkuil is planning to remove the g_mbus_config op. For now this
0010 driver uses the parsed DT bus config method until this issue is
0011 resolved.
0012
0013 2020-06: g_mbus has been removed in favour of the get_mbus_config pad
0014 operation which should be used to avoid parsing the remote endpoint
0015 configuration.
0016
0017 - This media driver supports inheriting V4L2 controls to the
0018 video capture devices, from the subdevices in the capture device's
0019 pipeline. The controls for each capture device are updated in the
0020 link_notify callback when the pipeline is modified. This feature should be
0021 removed, userspace should use the subdev-based userspace API instead.
0022
0023 - Similarly to the legacy control handling, legacy format handling where
0024 formats on the video nodes are influenced by the active format of the
0025 connected subdev should be removed.
0026
0027 - i.MX7: all of the above, since it uses the imx media core
0028
0029 - i.MX7: use Frame Interval Monitor
0030
0031 - imx7-media-csi: Restrict the supported formats list to the SoC version.
0032
0033 The imx7 CSI bridge can be configured to sample pixel components from the Rx
0034 queue in single (8bpp) or double (16bpp) component modes. Image format
0035 variants with different sample sizes (ie YUYV_2X8 vs YUYV_1X16) determine the
0036 pixel components sampling size per each clock cycle and their packing mode
0037 (see imx7_csi_configure() for details).
0038
0039 As the imx7 CSI bridge can be interfaced with different IP blocks depending on
0040 the SoC model it is integrated on, the Rx queue sampling size should match
0041 the size of the samples transferred by the transmitting IP block.
0042
0043 To avoid mis-configurations of the capture pipeline, the enumeration of the
0044 supported formats should be restricted to match the pixel source transmitting
0045 mode.
0046
0047 Example: i.MX8MM SoC integrates the CSI bridge with the Samsung CSIS CSI-2
0048 receiver which operates in dual pixel sampling mode. The CSI bridge should
0049 only expose the 1X16 formats variant which instructs it to operate in dual
0050 pixel sampling mode. When the CSI bridge is instead integrated on an i.MX7,
0051 which supports both serial and parallel input, it should expose both variants.
0052
0053 This currently only applies to YUYV formats, but other formats might need
0054 to be handled in the same way.
