Re: af9015/tda18218: Multiples (separates) usb devices errors/conflicts

[Jin Kazama <jin.ml@skynet.fr>]

On 9/24/11 12:06 AM, Antti Palosaari wrote:
> On 09/24/2011 12:06 AM, Jin Kazama wrote:
>> Hello,
>> I've been testing af9015/tda18218 based usb DVB-T tuners on a 2.6.39.4
>> kernel with the latest v4l drivers avaiable (from git).
>> When I'm using a single USB module, (listed as /dev/dvb/adapter0),
>> everything works fine.
>> When I'm plugging another module, at first it looks like everything's ok
>> (/dev/dvb/adapter1) and if I try to use this module while the adapter0
>> is not been used, it works - but if try to use both modules at the same
>> time, I get garbage output on both cards (error: warning: discontinuity
>> for PID... with dvblast on both cards.
>> Does anyone have any idea on how to fix this problem?
>
> Feel free to fix it. I am too busy currently.
>
Well, it looks like if I put 2 devices on different USB buses (on the 
same machine), they work fine, but if they're on the same USB bus, I get 
the problem...
I think the driver may get raw data from the USB bus - and the way it 
identifies the device is not the proper way (I have 2 exactly identical 
devices) => when both devices send data, the driver catches all the data 
from the bus, which is a corrupt mix of both streams...)
Unfortunately, I don't think that I'm capable of fixing the problem by 
myself, I don't even know which part of the driver to look for... if 
someone can give me a hint, I might *try* to *attempt* to fix it :)...