Hi Andy, On Sun, Jul 11, 2010 at 9:23 AM, Andy Walls <awalls@xxxxxxxxxxxxxxxx> wrote: > At the risk of missing something obvious: > > In your bridge driver's VIDIOC_S_STD ioctl() > > a. power up the analog tuner if it is not already > b. call s_std for the subdevices (including the tuner), > c. power down that analog tuner if not using the tuner input. > > No I2C errors in the log and the tuner is powered down when not in use, > > IMO, VIDIOC_S_STD is not a timing critical operation from userspace and > it doesn't happen that often. You can also filter the cases when > VIDIOC_S_STD is called on the same input, but the standard is not being > changed. Thanks for taking the time to provide feedback. It's not timing critical, but on some tuners initialization can take several seconds (e.g. tda18271, xc5000). I'm not thrilled about it taking 3-5 seconds to change the standard (something which some applications may very well do on every channel change). I'm tempted to just jam a zero into the tuner->tv_freq when powering down the tuner, but that's not a very clean solution obviously. The tuner core makes decisions based on tuner->tv_freq not being zero, so I believe tuner_core should provide some way to reset it back to zero as needed. Devin -- Devin J. Heitmueller - Kernel Labs http://www.kernellabs.com -- 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
