On Tue, Feb 2, 2010 at 7:29 PM, Mauro Carvalho Chehab <mchehab@xxxxxxxxxx> wrote: > The better is to allow enabling/disabling the anti-alias via ctrl. > Whatever default is chosen, the driver may adjust the control default > at the board initialization, or even blocking the control when the > other mode of operation is broken. > > I have here a few devices with saa7113 and saa7114. I think I have > also one device with saa7111, but I need to check. If I'm right, it will > take some time for me to prepare the saa7111 environment. The saa7113/7114 > devices are easier to setup, as they are usb. I actually am not very familiar with how custom controls work for v4l devices in terms of board specific configuration, as I'm more familiar with the way that you can provide a config struct during dvb_attach() for DVB devices. I've obviously seen how they can be set from userland, but have never dug into the specific as to how a bridge would set the parameters. I actually have a test tree here which includes the change (as well as a couple of unrelated em28xx fixes I'm working on). http://www.kernellabs.com/hg/~dheitmueller/em28xx-test The change in that tree just flips on the Anti-alias filter bit in the saa7115_misc_init struct, so it ends up being applied for 7113/7114/7115. However, I'm wondering if it makes sense to just have it on by default for all three boards (which is a *much* simpler change than adding a custom control and making sure it gets set properly by the bridge in all the various cases such as surviving a powerdown/powerup of the chip). BTW, the tree above just forces the bit on for all three boards - I'm not proposing that should be the final fix, but it is enough to allow people to evaluate the effects of the change. I've got a PVR-350 board with a saa7115 which I will do some testing on. If I see the artifacts on that board without the change, that bolsters the argument that the current default may just be wrong in general. Mauro, the hg logs suggest that you added the saa7115 support (and in fact appear to have introduced the issue in question). Do you remember what board you were using when you added the support? Also, how did you arrive at the defaults that you used? Were they based on some sort of i2c bus trace, or did you just set them by reading the datasheet? 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
