On Mon, 8 Feb 2010, Mauro Carvalho Chehab wrote: > In fact, on all drivers, there are devices that needs to be turn on only when > streaming is happening: sensors, analog TV/audio demods, digital demods. Also, > a few devices (for example: TV tuners) could eventually be on power off when > no device is opened. > > As the V4L core knows when this is happening (due to > open/close/poll/streamon/reqbuf/qbuf/dqbuf hooks, I think the runtime management > can happen at V4L core level. Well, we can move it up to v4l core. Should it get any more complicated than adding ret = pm_runtime_resume(&vdev->dev); if (ret < 0 && ret != -ENOSYS) return ret; to v4l2_open() and pm_runtime_suspend(&vdev->dev); to v4l2_release()? And to agree, that video drivers may set a device type to implement runtime PM, and that the v4l core shouldn't touch it? Then, for example, a bridge driver could implement such a device type instance and suspend or resume all related components? Thanks Guennadi --- Guennadi Liakhovetski, Ph.D. Freelance Open-Source Software Developer http://www.open-technology.de/ -- 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
