nanopi/allwinner i2c not working.

[Daniel Braniss]

> On 7 Oct 2020, at 09:32, Andriy Gapon <avg at FreeBSD.org> wrote:
> 
> On 06/10/2020 23:29, Daniel Braniss wrote:
>> 
>> 
>>> On 6 Oct 2020, at 17:22, Andriy Gapon <avg at FreeBSD.org
>>> <mailto:avg at FreeBSD.org>> wrote:
>>> 
>>> On 06/10/2020 17:00, Daniel Braniss wrote:
>>>> not too proud of it, but i’ll make it available.
>>>> it’s in https://www.cs.huji.ac.il/~danny/elockc.tar.bz
>>>> look in i2c.c
>>>> 
>>>> in any case it works fine in 12.1.
>>> 
>>> And it looks good to me as well.
>>> Could you please collect twsi debug output again?
>>> In head you do not need to recompile, you can just set hw.i2c.twsi_debug.
>> i did have to recompile
> 
> Oh, I thought I committed that change, but now I see that I have not.
> It is a part of D26049.
> 
>> iichb0: twsi_calc_baud_rate: Bus clock is at 24000000
>> iichb0: twsi_reset: Using clock param=59
>> iichb0: TWSI_WRITE: Writing 0 to 18
>> iichb0: TWSI_WRITE: Writing 59 to 14
>> iichb0: TWSI_WRITE: Writing 40 to c
>> iichb0: twsi_calc_baud_rate: Bus clock is at 24000000
>> iichb0: twsi_reset: Using clock param=59
>> iichb0: TWSI_WRITE: Writing 0 to 18
>> iichb0: TWSI_WRITE: Writing 59 to 14
>> iichb0: TWSI_WRITE: Writing 40 to c
>> iichb0: TWSI_WRITE: Writing c4 to c
>> iichb0: twsi_transfer: transmitting 2 messages
>> iichb0: TWSI_READ: read f8 from 10
>> iichb0: twsi_transfer: status=f8
>> iichb0: twsi_transfer: msg 0 is 9 bytes long
>> iichb0: twsi_transfer: msg 1 is 7 bytes long
>> iichb0: TWSI_WRITE: Writing e4 to c
>> iichb0: twsi_intr: Got interrupt Current msg=0
>> iichb0: TWSI_READ: read 8 from 10
>> iichb0: TWSI_READ: read cc from c
>> iichb0: twsi_intr: reg control=cc
>> iichb0: twsi_intr: Send the address (48)iichb0: TWSI_WRITE: Writing 48 to 8
> 
> Does that address (0x24 / 0x48 in 7-/8-bit representations) look correct?

100% correct

> 
>> iichb0: TWSI_WRITE: Writing c4 to c
>> iichb0: twsi_intr: Refresh reg_control
>> iichb0: TWSI_WRITE: Writing cc to c
>> iichb0: twsi_intr: Done with interrupts
>> 
>> iichb0: twsi_intr: Got interrupt Current msg=0
>> iichb0: TWSI_READ: read 20 from 10
>> iichb0: TWSI_READ: read cc from c
>> iichb0: twsi_intr: reg control=cc
>> iichb0: twsi_intr: No ack received after transmitting the address
> 
> The controller says that the device did not acknowledge its address.
> In other words, no device responded to the slave address.

but i2c -s 
> 
>> iichb0: twsi_intr: Refresh reg_control
>> iichb0: twsi_transfer: pause finish
>> iichb0: TWSI_WRITE: Writing 8 to c
>> iichb0: twsi_transfer: Error, aborting (2)
>> iichb0: twsi_intr: Done with interrupts
>> 
>> iichb0: TWSI_WRITE: Writing 0 to c
>> iichb0: TWSI_READ: read 30 from 10
>> iichb0: twsi_transfer: status=30
>> iichb0: TWSI_WRITE: Writing 0 to c
>> iichb0: TWSI_READ: read 30 from 10
>> iichb0: twsi_transfer: status=30
>> iichb0: TWSI_WRITE: Writing c4 to c
>> iichb0: twsi_transfer: transmitting 2 messages
>> iichb0: twsi_intr: Got interrupt Current msg=0
>> iichb0: TWSI_READ: read 30 from 10
>> iichb0: TWSI_READ: read 30 from 10
>> iichb0: twsi_transfer: status=30
>> iichb0: TWSI_READ: read cc from c
>> iichb0: twsi_transfer: msg 0 is 9 bytes long
>> iichb0: twsi_intr: reg control=cc
>> iichb0: twsi_transfer: msg 1 is 7 bytes long
>> 
>> iichb0: twsi_intr: status=30 hot handled
>> iichb0: TWSI_WRITE: Writing e4 to c
>> iichb0: twsi_intr: Refresh reg_control
>> iichb0: twsi_transfer: pause finish
>> iichb0: TWSI_WRITE: Writing 8 to c
>> iichb0: twsi_transfer: Error, aborting (1)
>> iichb0: twsi_intr: Done with interrupts
>> 
>> iichb0: TWSI_WRITE: Writing 0 to c
>> iichb0: TWSI_READ: read 10 from 10
>> iichb0: twsi_transfer: status=10
>> iichb0: TWSI_WRITE: Writing 0 to c
>> iichb0: TWSI_READ: read 10 from 10
>> iichb0: twsi_transfer: status=10
> 
> The rest reads like gibberish because the driver did not stop the controller
> after the NACK (also, possibly some log messages were omitted from your email).
> 
> I'd recommend once again to give https://reviews.freebsd.org/D26049 a try.
> I've just rebased it on the latest head, so it should apply cleanly.

i just downloaded it and will try - the sysctl for hw. is there.

(i did a git to get the latest current, i’ll try doing an svn update later -its bloody slow)
> 
> But as I said earlier, from the debug log it seems that the problem is either
> with the slave address or with the hardware (wiring, etc).

the hardware is fine, running 12.1 on it works ok.
and also i2c -s finds it.


> It's also possible that that was a transient condition.

not really, it seems to me some timming issue.

after a power cycle, and with debug on, all is working.
turning off debug only i2c -s works.

in any case will try the D26049 now.


> 
> -- 
> Andriy Gapon