Re: [PATCH v6 3/6] drm: Add driver for Solomon SSD130x OLED displays

From: andriy.shevchenko@xxxxxxxxxxxxxxx
Date: Mon Jun 13 2022 - 14:39:25 EST


On Mon, Jun 13, 2022 at 11:39:30AM +0000, Dominik Kierner wrote:
> On 5/25/2022 21:46, Javier Martinez Canillas wrote:

...

> > Thanks, I looked at the code briefly and think that there are things there that we
> > could use. I.e the 3-wire SPI support that's in panel-solomon-ssd130x-spi-3wire.c.
>
> When writing my driver code, I wasn't even considering using regmaps,
> like You did in Your I2C-Code. If that's applicable for 3-wire-SPI,
> it would likely be the better, more generic option. Your SPI-code
> reuses these parts to some extent. For that case,
> ssd130x_spi_regmap_config.reg_bits would need be changed to 1,
> as the "register address" has a length of 1 bit and we are sending
> 9 bits over the line and not 16.
> Since we still have 2 bytes of host memory,
> it should still be compatible with the 4-wire write, right?
> Or would 3-wire SPI require a second regmap?

I believe the cleanest solution is to have different regmap configurations.


--
With Best Regards,
Andy Shevchenko