Hi Tudor,
Am 2020-01-13 11:07, schrieb Michael Walle:
Btw. is renaming the flashes also considered a backwards incomaptible
change?
No, we can fix the names.
And can there be two flashes with the same name? Because IMHO it
would
be
I would prefer that we don't. Why would you have two different
jedec-ids with
the same name?
Because as pointed out in the Winbond example you cannot distiguish
between
W25Q32DW and W25Q32JWIQ; and in the Macronix example between MX25L8005
and
MX25L8006E. Thus my reasoning was to show only the common part, ie
W25Q32
or MX25L80 which should be the same for this particular ID. Like I
said, I'd
prefer showing an ambiguous name instead of a wrong one. But then you
may
have different IDs with the same ambiguous name.
Another solution would be to have the device tree provide a hint for the
actual flash chip. There would be multiple entries in the spi_nor_ids
with the
same flash id. By default the first one is used (keeping the current
behaviour). If there is for example
compatible = "jedec,spi-nor", "w25q32jwq";
the flash_info for the w25q32jwq will be chosen.
I know this will conflict with the new rule that there should only be
compatible = "jedec,spi-nor";
without the actual flash chip. But it seems that it is not always
possible
to just use the jedec id to match the correct chip.
Also see for example mx25l25635_post_bfpt_fixups() which tries to figure
out different behaviour by looking at "some" SFDP data. In this case we
might have been lucky, but I fear that this won't work in all cases and
for older flashes it won't work at all.
BTW I do not suggest to add the strings to the the spi_nor_dev_ids[].
I guess that would be a less invasive way to fix different flashes with
same jedec ids.
-michael
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