Re: [PATCH 04/22] [media] v4l2-subdev.h: add prepare_stream op

Sakari Ailus
2016-10-07T23:16:28Z

Hi Philipp,

On Fri, Oct 07, 2016 at 06:00:49PM +0200, Philipp Zabel wrote:
> In some cases, for example MIPI CSI-2 input on i.MX6, the sending and
> receiving subdevice need to be prepared in lock-step before the actual
> streaming can start. In the i.MX6 MIPI CSI-2 case, the sender needs to
> put its MIPI CSI-2 transmitter lanes into stop state, and the receiver
> needs to configure its D-PHY and detect the stop state on all active
> lanes. Only then the sender can be enabled to stream data and the
> receiver can lock its PLL to the clock lane.

Is there a need to explicitly control this? Shouldn't this already be the
case when the transmitting device is powered on and is not streaming?

--
Kind regards,

Sakari Ailus
e-mail: sakari.ailus@iki.fi XMPP: sailus@retiisi.org.uk