v4l2-subdev: add a v4l2_i2c_new_dev_subdev() function

Video (sub)devices, connecting to SoCs over generic i2c busses cannot provide a pointer to struct v4l2_device in i2c-adapter driver_data, and provide their own i2c_board_info data, including a platform_data field. Add a v4l2_i2c_new_dev_subdev() API function that does exactly the same as v4l2_i2c_new_subdev() but uses different parameters, and make v4l2_i2c_new_subdev() a wrapper around it.

Hi,

Quoted 6 lines · Guennadi Liakhovetski

Video (sub)devices, connecting to SoCs over generic i2c busses cannot provide a pointer to struct v4l2_device in i2c-adapter driver_data, and provide their own i2c_board_info data, including a platform_data field. Add a v4l2_i2c_new_dev_subdev() API function that does exactly the same as v4l2_i2c_new_subdev() but uses different parameters, and make v4l2_i2c_new_subdev() a wrapper around it.

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I am wondering about this ongoing effort and its pursued goal: is it to hierarchize the v4l architecture, adding new abstraction levels? If so, what for?

To me, as an eventual driver developer, this makes it harder to integrate my own drivers, as I use I2C and V4L in my system but I don't want them to be tightly coupled.

Of course I can ignore this "subdev" stuff and just link against soc-camera which is what I need, and manage I2C without V4L knowing about it. Which is what I do.