Re: [RFC PATCH 00/10] Netronix embedded controller driver for Kobo and Tolino ebook readers

On Sat, 4 Jul 2020 22:58:08 +0200
Jonathan Neuschäfer [off-list ref] wrote:

On Tue, Jun 30, 2020 at 10:14:47PM +0200, Andreas Kemnade wrote:

quoted

On Tue, 30 Jun 2020 09:15:23 +0200
Jonathan Neuschäfer [off-list ref] wrote:
  

quoted

On Tue, Jun 30, 2020 at 08:40:51AM +0200, Andreas Kemnade wrote:
[...]  

quoted

got a chance to test it on a Tolino Shine 2 HD.
It uses the RTC from the RC5T619 but backlight seems to go via MSP430
EC.

I got this.

[    1.453603] ntxec 0-0043: Netronix embedded controller version f110 detected.
[   10.723638] ntxec-rtc 21a0000.i2c:embedded-controller@43:rtc: registered as rtc0
[   10.775276] ntxec-pwm: probe of 21a0000.i2c:embedded-controller@43:pwm failed with error -5    

Hmm, -EIO from the PWM driver.
  

turing debugging on:  

(edited for compactness:)

quoted

[  330.332971] i2c i2c-0: write slave address: addr=0x86   ACK received
[  330.334420] i2c i2c-0: write byte: B0=0xA3              ACK received
[  330.334790] i2c i2c-0: write byte: B1=0x0               No ACK  

quoted

[  330.352339] i2c i2c-0: write slave address: addr=0x86   ACK received
[  330.362208] i2c i2c-0: write byte: B0=0xA1              ACK received
[  330.362479] i2c i2c-0: write byte: B1=0xFF              No ACK  

quoted

[  330.363112] i2c i2c-0: write slave address: addr=0x86   ACK received
[  330.363362] i2c i2c-0: write byte: B0=0xA2              ACK received
[  330.363608] i2c i2c-0: write byte: B1=0xFF              No ACK  

Hmm, it doesn't ack the writes to 0xA3, 0xA1 and 0xA2, which should
disable the PWM output and then disable the auto-off timer (according to
the vendor kernel).

And you said in your other mail that you can actually toggle the light
with writes to 0xA3, so I suspect a bug in the EC firmware here (which
may have gone unnoticed because the vendor kernel doesn't check if the
i2c transfers succeed). :/

That is a also my theory.

IMHO we should get this driver merged first, and perhaps add a quirk to
deal with the missing ACKs later (unless a better solution is found).

Yes, that can be done separately (after the Tolino Shine 2 HD dtb is
in, I am polishing it right now).

Regards,
Andreas

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