Re: pvrusb2: fix 7MHz & 8MHz DVB-T tuner support for HVR1900 revD1F5

From: Mauro Carvalho Chehab
Date: Mon Feb 27 2012 - 06:46:46 EST


Em 27-02-2012 07:15, Michael Krufky escreveu:
> On Fri, Feb 24, 2012 at 2:27 PM, Mauro Carvalho Chehab
> <mchehab@xxxxxxxxxx> wrote:
>> Em 07-02-2012 15:08, Michael Krufky escreveu:
>>> There are some new revisions of the HVR-1900 around whose DVB-T
>>> support is broken without this small bug-fix. Please merge asap -
>>> this fix needs to go to stable kernels as well. It applies cleanly
>>> against *all* recent kernels.
>>>
>>> The following changes since commit 805a6af8dba5dfdd35ec35dc52ec0122400b2610:
>>>
>>> Linux 3.2 (2012-01-04 15:55:44 -0800)
>>>
>>> are available in the git repository at:
>>> git://linuxtv.org/mkrufky/hauppauge surrey
>>>
>>> Michael Krufky (1):
>>> pvrusb2: fix 7MHz & 8MHz DVB-T tuner support for HVR1900 rev D1F5
>>>
>>> drivers/media/video/pvrusb2/pvrusb2-devattr.c | 10 ++++++++++
>>> 1 files changed, 10 insertions(+), 0 deletions(-)
>>
>>> The D1F5 revision of the WinTV HVR-1900 uses a tda18271c2 tuner
>>> instead of a tda18271c1 tuner as used in revision D1E9. To
>>> account for this, we must hardcode the frontend configuration
>>> to use the same IF frequency configuration for both revisions
>>> of the device.
>>
>> No, you don't need to hardcode the IF. Just use the get_if_frequency
>> callback at the demod, and it will work with whatever frequency you
>> use at the tuner.
>>
>> Regards,
>> Mauro
>
> (apologies for delayed reply - I am travelling in Europe this month
> and not checking all my email every day)
>
> Mauro,
>
> get_if_frequency will work, but for *optimal* settings for the
> hardware that my company manufactures, this is it. The hardcoded IF
> is the correct setting for *this* hardware. There are more factors
> than just a tuner and demodulator, here. I know the board layout and
> the crystal configurations, and we did extensive testing. Sure, you
> can use get_if_frequency and it will "work" ... but when I have
> information about how it will work *best* then you should merge my
> patch.

Well, your patch description doesn't say that. Instead, it makes anyone
reading it that you'll be using a sub-optimal configuration due to some
Linux driver limitation.

> This is the fix. You can merge it or you will not merge it. I did my
> part, Mauro. My customers need this fix and I will not argue.

> ALSO, for -stable, there is no get_if_frequency. I cannot have the
> patch merged into stable unless you merge it into mainline. There is
> no time for opinion - only facts.

No. get_if_frequency is on Kernel 3.2.

> Please merge.

Please fix the description and I'll apply it.


>
> -MK

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/