RE: [PATCH v2] spi: add Renesas RPC-IF driver

Chris Brandt
2020-02-07T22:36:42Z

On Wed, Jan 15, 2020, Sergei Shtylyov wrote:
> Add the SPI driver for the Renesas RPC-IF. It's the "front end" driver
> using the "back end" APIs in the main driver to talk to the real hardware.
> We only implement the 'spi-mem' interface -- there's no need to implemebt
> the usual SPI driver methods...

I tried these patches on an RZ/A1H RSK board.

At first, things were looking good. It would probe the SPI flash correctly
and I could read out data.

But, when I went to try and do an erase, it all went bad.
Looking at the actual SPI lines, the commands coming out don't look like what
I would expect from an MTD device.

For example, I do a
$ flash_eraseall /dev/mtd3
and all that comes out are Read Status commands (0x05).
All the write enables and erase commands are missing.

So, it looks like any command that is a write-only never actually sends
anything.

I did try and do a page program command:
$ echo hello > /dev/mtd3
It sent the page program command (0x12), but in this case, it still didn't work
because a write enable command was not sent first.
I assume the MTD layer is requesting the correct sequence of commands, but
Somehow this new driver is dropping of them.

Chris