Hi everybody, Trying to implement support for multiple sensors connected to the same OMAP3 ISP input (all but one of the sensors need to be kept in reset obviously), I need to associate host-specific data to the sensor subdevs. The terms host and bridge are considered as synonyms in the rest of this e- mail. The OMAP3 ISP platform data has interface configuration parameters for the two CSI2 (a and c), CCP2 and parallel interfaces. The parameters are used to configure the bus when a sensor is selected. To support multiple sensors on the same input, the parameters need to be specified per-sensor, and not ISP- wide. No issue in the platform data. Board codes declare an array of structures that embed a struct v4l2_subdev_i2c_board_info instance and an OMAP3 ISP-specific interface configuration structure. At runtime, when a sensor is selected, I need to access the OMAP3 ISP-specific interface configuration structure for the selected sensor. At that point all I have is a v4l2_subdev structure pointer, without a way to get back to the interface configuration structure. The only point in the code where the v4l2_subdev and the interface configuration data are both known and could be linked together is in the host driver's probe function, where the v4l2_subdev instances are created. I have two solutions there: - store the v4l2_subdev pointer and the interface configuration data pointer in a host-specific array, and perform a an array lookup operation at runtime with the v4l2_subdev pointer as a key - add a void *host_priv field to the v4l2_subdev structure, store the interface configuration data pointer in that field, and use the field at runtime The second solution seems cleaner but requires an additional field in v4l2_subdev. Opinions and other comments will be appreciated. -- Regards, Laurent Pinchart -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
