Re: [PATCH] Add spi-nor driver for Realtek RTL838x/RTL839x switch SoCs

[Chuanhong Guo]

Hi!

On Wed, Dec 16, 2020 at 4:30 PM <Tudor.Ambarus@xxxxxxxxxxxxx> wrote:
>
> On 12/15/20 11:46 PM, Bert Vermeulen wrote:
> > This driver supports the spiflash core in all RTL838x/RTL839x SoCs,
> > and likely some older models as well (RTL8196C).
> >
> Can we use SPIMEM and move this under drivers/spi/ instead?
>
> Cheers,
> ta

Just took a brief look at the code, and here's my current understanding
of this controller:
1. CS is controlled separately with SFCSR_CSB* bits
2. To write 1-4 bytes, set SFCSR_LEN* and write to SFDR
2. To read 1-4 bytes, set SFCSR_LEN* and read SFDR

If that's true, this is a generic half-duplex spi controller, and the driver
should register a spi_controller with set_cs and transfer_one
implemented.

-- 
Regards,
Chuanhong Guo