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

[Andreas Kemnade]

On Tue, 30 Jun 2020 09:15:23 +0200
Jonathan Neuschäfer <j.neuschaefer at gmx.net> wrote:

> On Tue, Jun 30, 2020 at 08:40:51AM +0200, Andreas Kemnade wrote:
> [...]
> > 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 at 43:rtc: registered as rtc0
> > [   10.775276] ntxec-pwm: probe of 21a0000.i2c:embedded-controller at 43:pwm failed with error -5  
> 
> Hmm, -EIO from the PWM driver.
>
Weird...
IOMUXC_SW_PAD_CTL_PAD_I2C1_SDA/SCL is identical between
vendor kernel (heavily patched 3.0.35) and patched mainline.
                        
MX6SL_PAD_I2C1_SCL__I2C1_SCL     0x4001f8b1
MX6SL_PAD_I2C1_SDA__I2C1_SDA     0x4001f8b1

root at tolino2:~# i2cset -f 0 0x43 0xa3 0x0001 w
WARNING! This program can confuse your I2C bus, cause data loss and worse!
I will write to device file /dev/i2c-0, chip address 0x43, data address
0xa3, data 0x01, mode word.
Continue? [Y/n] 
Error: Write failed
root at tolino2:~# i2cset -f 0 0x43 0xa3 0x0000 w
WARNING! This program can confuse your I2C bus, cause data loss and worse!
I will write to device file /dev/i2c-0, chip address 0x43, data address
0xa3, data 0x00, mode word.
Continue? [Y/n] 
Error: Write failed

but backlight gets toggled. Same behavior on vendor kernel and
in vendor uboot.
That smells.

Regards,
Andreas