Re: [Qemu-devel] [PATCH RFC] i2c-tiny-usb

[Tim Sander <tim@krieglstein.org>]

Hi Paolo

Am Freitag, 27. November 2015, 10:32:25 schrieb Paolo Bonzini:
> On 26/11/2015 17:35, Tim Sander wrote:
> > Below is a patch implementing the i2c-tiny-usb device.
> > I am currently not sure about the i2c semantics. I think
> > incrementing the address on longer reads is wrong?
> 
> Yes, it is.  This is a bus address, not an address inside the device.
>
> Also you should only call i2c_start_transfer/i2c_end_transfer once.
Good to know. 

I have one more thing, i2cdetect looks like this:
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:          03 04 05 06 07 08 09 0a 0b 0c 0d 0e 0f 
10: 10 11 12 13 14 15 16 17 18 19 1a 1b 1c 1d 1e 1f 
20: 20 21 22 23 24 25 26 27 28 29 2a 2b 2c 2d 2e 2f 
30: 30 31 32 33 34 35 36 37 38 39 3a 3b 3c 3d 3e 3f 
40: 40 41 42 43 44 45 46 47 48 49 4a 4b 4c 4d 4e 4f 
50: 50 51 52 53 54 55 56 57 58 59 5a 5b 5c 5d 5e 5f 
60: 60 61 62 63 64 65 66 67 68 69 6a 6b 6c 6d 6e 6f 
70: 70 71 72 73 74 75 76 77

But i only have a device at 0x50 so most numbers should be "--".
I know that i just have to set the read length to zero, to archive that. 
Currently i don't know how to determine if there is something registered on
the requested i2c address?

Best regards
Tim