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cx88 default contrast,volume,balance

Ian Pickworth wrote:

Hello List,
Does no one want to adopt this poor little orphaned patch? Its a very good patch :-).

Ian-

Thank you for pushing forward on this... I personally can not apply it, because last I knew, Mauro was working on it. I dont know why he never responded to your post here, but perhaps you should send it to the list again (after addressing my comments) and cc Mauro's infradead email.

Apart from that, I have some comments inline below:

Ian Pickworth wrote:

Hello List,
This patch was proposed by Marcin Rudowski about a month ago, and I think it has got lost in the activity at the time. I have thus remade the patch to work on the latest CVS copy (as of "2006-01-21 04:42 mcisely" in the changelog).

I have been running with this patch for some time now, and appreciate the default settings being correct by default, so I think it would be a good improvement for cx88 users.

I have to stress that the hard work in this was done by Marcin and Mauro.

The patch signature is as follows:
---------
       * linux/drivers/media/video/cx88/cx88-video.c: (get_control),
       (set_control), (init_controls), (cx88_do_ioctl):
       - Do some cleanups at cx88-video
       - Fixed a bug at balance control, when set to 0x40
       - improved debug messages
       - fixed default for contrast

       Signed-off-by: Ian Pickworth <ian (at) pickworth.me.uk>
       Signed-off-by: Marcin Rudowski <mar_rud (at) poczta.onet.pl>
       Signed-off-by: Mauro Carvalho Chehab <mchehab (at) brturbo.com.br>

[snip]

--- v4l-dvb/linux/drivers/media/video/cx88/cx88-video.c 2006-01-11 19:28:02.000000000 +0000
+++ v4l-dvb.test/linux/drivers/media/video/cx88/cx88-video.c 2006-01-21 14:55:19.000000000 +0000
(at) (at) -267,7 +267,7 (at) (at) .minimum = 0,
.maximum = 0xff,
.step = 1,
- .default_value = 0x3f,
+ .default_value = 0x39, 

[snip]

We have decided to leave the default value at 0x3f, regardless of what the datasheet says, regardless of what the other drivers are doing. This is a tiny change, and really isnt necessary, considering that 0x3f is truly 50% of 0x7f , which SHOULD be the maximum value...

However, the maximum value for contrast is currently 0xff, which is utterly rediculous if you ask me, unless you guys like to watch television shows starring polar bears running through snowstorms.

I propose the following patch (also located at http://linuxtv.org/~mkrufky/pending/cx88-contrast-max-fix.patch) :

--- linux/drivers/media/video/cx88/cx88-video.c 10 Nov 2005 12:40:42 -0000 1.102
+++ linux/drivers/media/video/cx88/cx88-video.c 8 Dec 2005 12:55:45 -0000
(at) (at) -264,7 +264,7 (at) (at) static struct cx88_ctrl cx8800_ctls[] = .id = V4L2_CID_CONTRAST,
.name = "Contrast",
.minimum = 0,
- .maximum = 0xff,
+ .maximum = 0x7f,
.step = 1,
.default_value = 0,
.type = V4L2_CTRL_TYPE_INTEGER,


Thanks to: Jelle Foks <jelle (at) foks.8m.com>
Signed-off-by: Michael Krufky <mkrufky (at) linuxtv.org>

I owe the credit of this patch to Jelle Foks, who actually started this whole effort of fixing this stuff in December. Unfortunately, Mauro will not allow me to apply this, because it decreases the contrast range by half. I think his reasoning is silly, because there will never be a need to use a setting above 0x7f.

Ian, maybe you can try that patch and we can build a case and convince Mauro to allow it?

I think the rest of this patch was interpolation stuff, which shouldnt be required given the trivial fix above. Once again, maybe interpolation is the way to go, but I think that simple changing max to 0x7f is sufficient, and WAAAAY cleaner.

Anyhow, if you split your patch up into separate patches, one to handle contrast, one to handle volume, and the last for balance, maybe then it will be easier to push them through the beaurocracy.

Thanks for not giving up hope,

Michael Krufky


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