[mythtv-users] hdpvr latest firmware color saturation issue question

[Steven Adeff]

On Sun, Jul 22, 2012 at 9:15 PM, Devin Heitmueller
<dheitmueller at kernellabs.com> wrote:
> On Sun, Jul 22, 2012 at 7:14 PM, Gary Buhrmaster
> <gary.buhrmaster at gmail.com> wrote:
>> FD: I do not have a HD-PVR, so I have no standing in this debate.
>>
>> When the driver is actually wrong, such patches should
>> be submitted/applied upstream (in the driver).  That means
>> everyone is a winner.
>>
>> Rather than hardcoding a fixup, is not a better temporary patch
>> (until you get the patch into the kernel) is to set the initial values
>> at the device creation to be "more reasonable", and let the user
>> decide for themselves what the correct values should be set to
>> for their unique cases (the linux way is to allow one to shoot
>> ones-self in the foot, or whatever exposed body part one wants
>> to aim at).  I am in favor of good defaults.  I am not in favor of
>> taking away my good judgement.
>
> This is *not* a driver bug.  The assumption that 50% of the
> operational range of any given control is a valid default is fatally
> flawed.
>
> For every control, the driver reports the minimum value, maximum,
> step, and the default.  See here for more info:
>
> http://linuxtv.org/downloads/v4l-dvb-apis/vidioc-queryctrl.html
>
> The application should read the default value out of the driver.  If
> the application isn't using VIDIOC_QUERYCTRL to determine the default
> value for the control, it is broken.
>
> All that said, if the driver *is* returning a wonky default, then
> *that* is a driver bug (but I doubt that is the case here).
>
> Devin

so, does anyone actually know what *is* going on then between the
newer firmware and the drivers? Apparently there is a "fix" in the
driver for whatever is causing the issue. It sounds like the firmware
won't change, as perhaps Hauppauge doesn't see it as a bug, just a
change in how the firmware works, something the driver must then
"adjust" for. It sounds like in kernel 3.4 the driver has been updated
to do so, but for older kernels it has not.

While I agree best to adjust in the driver, running 3.4 is not
necessarily the easiest, and if a small quick patch can be put in
MythTV with a "fix saturation bug" checkbox or some such, at least us
MythTV users won't have to worry about it until the 3.4 and newer
kernels become more common.

-- 
Steve
http://www.mythtv.org/wiki/User:Steveadeff
Before you ask, read the FAQ!
http://www.mythtv.org/wiki/Frequently_Asked_Questions
then search the Wiki, and this list,
http://www.gossamer-threads.com/lists/mythtv/
Mailinglist etiquette - http://www.mythtv.org/wiki/Mailing_List_etiquette