Re: [PATCH] mxl111sf: revert patch: fix error on stream stop in mxl111sf_ep6_streaming_ctrl()

[Antti Palosaari <crope@iki.fi>]

On 10/05/2012 11:58 PM, Michael Krufky wrote:
> On Fri, Oct 5, 2012 at 4:54 PM, Antti Palosaari <crope@iki.fi> wrote:
>> On 10/05/2012 11:49 PM, Michael Krufky wrote:
>>>
>>> On Fri, Oct 5, 2012 at 4:44 PM, Antti Palosaari <crope@iki.fi> wrote:
>>>>
>>>> This reverts commits:
>>>> 3fd7e4341e04f80e2605f56bbd8cb1e8b027901a
>>>> [media] mxl111sf: remove an unused variable
>>>> 3be5bb71fbf18f83cb88b54a62a78e03e5a4f30a
>>>> [media] mxl111sf: fix error on stream stop in
>>>> mxl111sf_ep6_streaming_ctrl()
>>>>
>>>> ...as bug behind these is fixed by the DVB USB v2.
>>>>
>>>> Cc: Michael Krufky <mkrufky@linuxtv.org>
>>>> Signed-off-by: Antti Palosaari <crope@iki.fi>
>>>> ---
>>>>    drivers/media/usb/dvb-usb-v2/mxl111sf.c | 7 +++++--
>>>>    1 file changed, 5 insertions(+), 2 deletions(-)
>>>>
>>>> diff --git a/drivers/media/usb/dvb-usb-v2/mxl111sf.c
>>>> b/drivers/media/usb/dvb-usb-v2/mxl111sf.c
>>>> index efdcb15..fcfe124 100644
>>>> --- a/drivers/media/usb/dvb-usb-v2/mxl111sf.c
>>>> +++ b/drivers/media/usb/dvb-usb-v2/mxl111sf.c
>>>> @@ -343,6 +343,7 @@ static int mxl111sf_ep6_streaming_ctrl(struct
>>>> dvb_frontend *fe, int onoff)
>>>>           struct mxl111sf_state *state = fe_to_priv(fe);
>>>>           struct mxl111sf_adap_state *adap_state =
>>>> &state->adap_state[fe->id];
>>>>           int ret = 0;
>>>> +       u8 tmp;
>>>>
>>>>           deb_info("%s(%d)\n", __func__, onoff);
>>>>
>>>> @@ -353,13 +354,15 @@ static int mxl111sf_ep6_streaming_ctrl(struct
>>>> dvb_frontend *fe, int onoff)
>>>>
>>>> adap_state->ep6_clockphase,
>>>>                                                 0, 0);
>>>>                   mxl_fail(ret);
>>>> -#if 0
>>>>           } else {
>>>>                   ret = mxl111sf_disable_656_port(state);
>>>>                   mxl_fail(ret);
>>>> -#endif
>>>>           }
>>>>
>>>> +       mxl111sf_read_reg(state, 0x12, &tmp);
>>>> +       tmp &= ~0x04;
>>>> +       mxl111sf_write_reg(state, 0x12, tmp);
>>>> +
>>>>           return ret;
>>>>    }
>>>>
>>>
>>>
>>> I disabled that code on purpose - its redundant.  please do not apply
>>> this patch.
>>
>>
>> According to comments you have added patch changelog you disabled it doe to
>> that bug:
>>
>>
>> [media] mxl111sf: fix error on stream stop in mxl111sf_ep6_streaming_ctrl()
>>
>> Remove unnecessary register access in mxl111sf_ep6_streaming_ctrl()
>>
>> This code breaks driver operation in kernel 3.3 and later, although
>> it works properly in 3.2  Disable register access to 0x12 for now.
>>
>>
>>
>> are you saying there is some other reason than mentioned here? I am quite
>> 100% sure I fixed that bug in dvb-usb.
>>
>> regards
>> Antti
>> --
>> http://palosaari.fi/
>
> Yup... there is indeed another reason.  However, if you want to push a
> new patch that just removes the #if 0's, that would be fine.  Please
> test first, of course.
>
> Just a warning, MH support is broken now and I haven't yet had a
> chance to track that down yet...  Luckily, merge window rules dont
> apply to regressions.  (it worked in 3.5 w/ dvb-usb before the forced
> change to 'dvb-usb-v2')
>
> I plan to (hopefully) do a full qual this weekend and hopefully push
> patches as needed.

I cannot test it properly with DVB-T as EP6 is not used for DVB-T. Only 
some stupid "dry rans". Did you saw yourself "dvb-usb: error while 
stopping stream." ? If yes, then you could likely test it. But in any 
case, you know what that reg bit is and if it is necessary or not. 
Likely not important.

regards
Antti

-- 
http://palosaari.fi/