Re: [PATCH v3 11/11] serial: sc16is7xx: add dump registers function

From: andy . shevchenko
Date: Thu May 25 2023 - 07:26:52 EST


Thu, May 25, 2023 at 12:03:25AM -0400, Hugo Villeneuve kirjoitti:
> From: Hugo Villeneuve <hvilleneuve@xxxxxxxxxxxx>
>
> With this driver, it is very hard to debug the registers using
> the /sys/kernel/debug/regmap interface.
>
> The main reason is that bits 0 and 1 of the register address
> correspond to the channels bits, so the register address itself starts
> at bit 2, so we must 'mentally' shift each register address by 2 bits
> to get its offset.
>
> Also, only channels 0 and 1 are supported, so combinations of bits
> 0 and 1 being 10b and 11b are invalid, and the display of these
> registers is useless.
>
> For example:
>
> cat /sys/kernel/debug/regmap/spi0.0/registers
> 04: 10 -> Port 0, register offset 1
> 05: 10 -> Port 1, register offset 1
> 06: 00 -> Port 2, register offset 1 -> invalid
> 07: 00 -> port 3, register offset 1 -> invalid
> ...
>
> Add a debug module parameter to call a custom dump function for each
> port registers after the probe phase to help debug.

Not sure about this. Can we rather create an abstract mapping on regmap?
(Something like gpio-pca953x.c has)

--
With Best Regards,
Andy Shevchenko