Re: Sabrent (stk1160) / Easycap driver problem

Re: Sabrent (stk1160) / Easycap driver problem

[Ezequiel Garcia]

Hi Philippe,

Ccing the linux-media ML. Please don't reply dropping the Cc!

2015-12-02 11:58 GMT-03:00 Philippe Desrochers <desrochers.philippe@gmail.com>:
> Hello Ezequiel,
>
> I'm using your stk1160 driver with some EasyCap (china) clone and it is
> working fine.
>
> However, a few days ago, I bought two Sabrent USB-AVCPT and both of them are
> not working with my Ubuntu 14.04 computer.
> http://www.sabrent.com/category/video-converters/USB-AVCPT/
>
> All of these devices have the Syntek 1160 chipset.
>
> Normally, I am using VLC to use these devices but with the Sabrent grabber I
> can't see the video/display window. (it just does not show)
>
> I also tried mplayer and it is giving me a "select timeout".
>
> See attached file for the "lsusb -vv" output.
>
> Can you give me some hint where to look for to fix this issue ?
> If needed, I can compile code or driver and do some tests.
>
> For now, I am a bit lost because I don't know where to start looking...
>

Can you paste the kernel log (dmesg output) in each case?


-- 
Ezequiel García, VanguardiaSur
www.vanguardiasur.com.ar

Re: Sabrent (stk1160) / Easycap driver problem

[Ezequiel Garcia]

On 2 December 2015 at 14:43, Philippe Desrochers
<desrochers.philippe@gmail.com> wrote:
> I'm sending the email again (in plain text) since it seems it was blocked by
> the server.
>
> EASYCAP CHINA CLONE (OK):
> [ 8630.596236] usb 2-1: new high-speed USB device number 6 using ehci-pci
> [ 8630.729074] usb 2-1: New USB device found, idVendor=05e1, idProduct=0408
> [ 8630.729084] usb 2-1: New USB device strings: Mfr=1, Product=2,
> SerialNumber=0
> [ 8630.729091] usb 2-1: Product: USB 2.0 Video Capture Controller
> [ 8630.729097] usb 2-1: Manufacturer: Syntek Semiconductor
> [ 8630.729648] usb 2-1: New device Syntek Semiconductor USB 2.0 Video
> Capture Controller @ 480 Mbps (05e1:0408, interface 0, class 0)
> [ 8630.729656] usb 2-1: video interface 0 found
> [ 8631.242258] saa7115 7-0025: saa7113 found @ 0x4a (stk1160)

Hmm.. seems the bad device doesn't found a decoder chip. Let me
refresh my mind and get back to you.
-- 
Ezequiel García, VanguardiaSur
www.vanguardiasur.com.ar

Re: Sabrent (stk1160) / Easycap driver problem

[Ezequiel Garcia]

On 5 December 2015 at 01:29, Philippe Desrochers
<desrochers.philippe@gmail.com> wrote:
> The difference seems to be around the "saa7113" chip. Maybe the Sabrent is
> using another video decoder chip ?

Yes, I believe that would explain the kernel log you sent.

> I will open one and check the chips on the PCB.
>

OK, that would help.

> Do you know if the stk1160 driver was working with this device (Sabrent
> USB-AVCPT) in the past ?
>

I've only seen generic "Easycap" labeled stk1160 devices
with either sa7115 or gm7113 decoder. Both of these are supported.c

See drivers/media/i2c/saa7115.c:saa711x_detect_chip for details on how
the decoder chip
is identified.

> Also, it seems the Sabrent USB-AVCPT is using the AC'97 Audio chip.
> Could it be the problem ?
>

Shouldn't affect.

> Do you know if there a firmware in the Syntek 1160 chip ?
>

There is not.
-- 
Ezequiel García, VanguardiaSur
www.vanguardiasur.com.ar

Re: Sabrent (stk1160) / Easycap driver problem

[Ezequiel Garcia]

(shoot, we dropped the ML somewhere along the conversation)

>> On 7 December 2015 at 12:32, Philippe Desrochers
>> <desrochers.philippe@gmail.com> wrote:
>> > Hello again,
>> >
>> > I open the device and I saw the following chips:
>> >
>> > SYNTEK:
>> > STK1160DLQG
>> > D7A155G-1513
>> >
>> > VIDEO DECODER:
>> > CJC7113
>> >
>> > AUDIO:
>> > ALC655
>> > 64231N1 L620D
>> >
>> > It seems the video decoder is a clone of the Philips SAA7113.
>> > Do you know if the CJC7113 is supported by the STK1160 linux driver ?
>> >
>>
>> It will probably work, being a clone of saa7113. But for some reason,
>> saa7115 is not detecting it. Maybe you can try to debug that and see
>> what's going on?


On 7 December 2015 at 14:45, Philippe Desrochers
<desrochers.philippe@gmail.com> wrote:
> Yes, I will try. I'm still not very experienced with linux kernel/driver...
> I think I can manage that since I have a good background in embedded system
> (Microcontroller).
>
> In just few lines, can you tell me how the STK1160 and SA7115 are related to
> each other ?
> Can I see it as 2 independent modules ? (I mean with SA7115 loaded first and
> then STK1160 loaded after only if the first module is OK ?)
>

Sure. On the hardware side, stk1160 is the USB chipset, while the
saa7115-compatible IC is the analog video decoder chip. stk1160 and
saa7115 talk through a I2C bus that's in the capture card.

On the software side, we have a similar model: the stk1160 driver
deals with the USB data and the saa7115 driver talks to the decoder
chip (through the I2C bus). Since saa7115 talks through I2C, you'll
find it under drivers/media/i2c.

stk1160 creates a subdevice that is owned by saa7115 driver. The
latter knows there's a chip on some i2c address, and then probes for
the type if chip.

I believe probing is done on saa711x_detect_chip(). To support your
device, we may have to create a new supported model here:

enum saa711x_model {
        SAA7111A,
        SAA7111,
        SAA7113,
        GM7113C,
        SAA7114,
        SAA7115,
        SAA7118,
};

If you grep GM7113C through the sources you'll be able to see how
differences between models are handled. Maybe your chip is not really
different from GM7113C or SAA7113 and all we need is to make sure it's
detected.

Don't hesitate to ask for more help over here.
-- 
Ezequiel García, VanguardiaSur
www.vanguardiasur.com.ar

Re: Sabrent (stk1160) / Easycap driver problem

[Ezequiel Garcia]

Hi Philippe,

On 20 December 2015 at 20:32, Philippe Desrochers
<desrochers.philippe@gmail.com> wrote:
> Hello Ezequiel,
>
> I tested with saa7115.c and the problem is in the "saa711x_detect_chip"
> function.
> In fact, the CJC7113 chip seems to returns all '1' when reading register 0.
>  ("1111111111111111" found @ 0x4a (stk1160)))
>
> I made a test by returning "SAA7113" without taking care of the value read
> from the CJC7113.
> By doing that, I was able to make the device work with VLC in Ubuntu 14.04.
>

That's good news, isn't it?

> I tried to find the datasheet of this CJC7113 chip but it does not seems to
> be available on the web.
>
> I will contact Sabrent for support and datasheet.
> If I get some positive response I think I will patch the driver otherwise I
> will select another dongle.
>

FWIW, I believe a patch to make CJC7113 detected as SAA7113 would
be acceptable.
-- 
Ezequiel García, VanguardiaSur
www.vanguardiasur.com.ar