Re: Wrongly identified easycap em28xx

["Frank Schäfer" <fschaefer.oss@googlemail.com>]

Am 18.02.2013 23:36, schrieb Mr Goldcove:
> I've only tried composite video input.
> The video/ audio output is good.
>  
> It has the following input:
> RCA stereo sound
> RCA video
> S-video
>
> It has no push button but has a green led which illuminates when the
> device is in use.
>
>
> On 18. feb. 2013 22:25, Frank Schäfer wrote:
>> Am 18.02.2013 21:53, schrieb Mr Goldcove:
>>> "Easy Cap DC-60++"
>>> Wrongly identified as card 19 "EM2860/SAA711X Reference Design",
>>> resulting in no audio.
>>> Works perfectly when using card 64 "Easy Cap Capture DC-60"
>> Video inputs work fine, right ?
>> Does this device has any buttons / LEDs ?
>>
>> The driver doesn't handle devices with generic IDs very well.
>> In this case we can conclude from the USB PID that the device has audio
>> support (which is actually the only difference to board
>> EM2860_BOARD_SAA711X_REFERENCE_DESIGN).
>> But I would like to think twice about it, because this kind of changes
>> has very a high potential to cause regressions for other boards...
>>
>> Regards,
>> Frank

After thinking about this for some minutes:
The easiest soulution would be, to add .amux = EM28XX_AMUX_LINE_IN lines
to input definitions of board EM2860_BOARD_SAA711X_REFERENCE_DESIGN.
No additional code lines (check for audio support etc.) would be needed
and (as side effect) board EM2860_BOARD_EASYCAP would become obsolete.

The last modification of board EM2860_BOARD_SAA711X_REFERENCE_DESIGN was
commit 3ed58baf5db4eab553803916a990a3dbca4dc611 from Devin.
The commit message says

"The device provides the audio through a pass-thru cable, so we don't need
 an actual audio capture profile (neither the K-World device nor the
Pointnix
 have an onboard audio decoder)"

Changing the .amux settings doesn't cause any trouble for devices
without audio support
(there is actually no way to define _no_ amux, without this line in the
input definition .amux is 0 = EM28XX_AMUX_VIDEO).

BUT: as we are talking about devices with generic USB IDs, we don't (and
will never) know about all other existing devices.
There _might_ be some unknown devices with audio support, which are
working silently with the current audio settings for board
EM2860_BOARD_SAA711X_REFERENCE_DESIGN.

OTOH: if we keep the two separate boards and switch from board
EM2860_BOARD_SAA711X_REFERENCE_DESIGN to board EM2860_BOARD_EASYCAP when
the device has audio support,
the same shit can happen.

Thoughts ?
Does anyone know how the Empia-driver handles devices with generic IDs ?
Do you think we can assume their driver uses a single reference board
design for the detected combination of USB-ID and subdevices ?

Regards,
Frank



>>
>>> **Interim solution**
>>> load module (before inserting the EasyCap. I'm having trouble if the
>>> module is loaded/unloaded with different cards...)
>>> modprobe em28xx card=64
>>>   or
>>> add "options em28xx card=64" to /etc/modprobe.d/local.conf
>>>
>>> **hw info**
>>> Bus 002 Device 005: ID eb1a:2861 eMPIA Technology, Inc.
>>>
>>> Chips:
>>> Empia EM2860 P7JY8-011 201023-01AG
>>> NXP SAA7113H
>>> RMC ALC653 89G06K1 G909A
>>>
>>> **logs**
>>> [ 5567.367883] em28xx: New device @ 480 Mbps (eb1a:2861, interface 0,
>>> class 0)
>>> [ 5567.367985] em28xx #0: chip ID is em2860
>>> [ 5567.380645] IR MCE Keyboard/mouse protocol handler initialized
>>> [ 5567.384202] lirc_dev: IR Remote Control driver registered, major 249
>>> [ 5567.385468] IR LIRC bridge handler initialized
>>> [ 5567.460386] em28xx #0: board has no eeprom
>>> [ 5567.534612] em28xx #0: found i2c device @ 0x4a [saa7113h]
>>> [ 5567.568303] em28xx #0: Your board has no unique USB ID.
>>> [ 5567.568308] em28xx #0: A hint were successfully done, based on i2c
>>> devicelist hash.
>>> [ 5567.568312] em28xx #0: This method is not 100% failproof.
>>> [ 5567.568314] em28xx #0: If the board were missdetected, please email
>>> this log to:
>>> [ 5567.568317] em28xx #0:     V4L Mailing List 
>>> <linux-media@vger.kernel.org>
>>> [ 5567.568321] em28xx #0: Board detected as EM2860/SAA711X Reference Design
>>> [ 5567.647433] em28xx #0: Identified as EM2860/SAA711X Reference Design
>>> (card=19)
>>> [ 5567.647438] em28xx #0: Registering snapshot button...
>>> [ 5567.647531] input: em28xx snapshot button as
>>> /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.4/input/input11
>>> [ 5568.019310] saa7115 15-0025: saa7113 found (1f7113d0e100000) @ 0x4a
>>> (em28xx #0)
>>> [ 5568.789385] em28xx #0: Config register raw data: 0x10
>>> [ 5568.813055] em28xx #0: AC97 vendor ID = 0x414c4761
>>> [ 5568.825074] em28xx #0: AC97 features = 0x0000
>>> [ 5568.825078] em28xx #0: Unknown AC97 audio processor detected!
>>> [ 5569.284137] em28xx #0: v4l2 driver version 0.1.3
>>> [ 5570.305831] em28xx #0: V4L2 video device registered as video1
>>> [ 5570.305835] em28xx #0: V4L2 VBI device registered as vbi0
>>> [ 5570.305862] em28xx audio device (eb1a:2861): interface 1, class 1
>>> [ 5570.305877] em28xx audio device (eb1a:2861): interface 2, class 1
>>> [ 5570.305906] usbcore: registered new interface driver em28xx
>>> [ 5570.305909] em28xx driver loaded
>>> [ 5570.392917] usbcore: registered new interface driver snd-usb-audio
>>> [ 7903.785365] em28xx #0: vidioc_s_fmt_vid_cap queue busy
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