On 03/04/2014 10:00 PM, Sören Brinkmann wrote:
On Tue, 2014-03-04 at 10:06PM +0200, Eli Billauer wrote:
Hello Sören,
wp-inverted solves the practical problem indeed, and fools the
driver into thinking that the card has an inverted write protection
sensor, and the logic zero that it finds in the hardware register
means that the card isn't write protected.
I'm insisting on this patch, because I think that the device tree
should describe the hardware as it is, and not fool the driver into
behaving the way we want it to. These tricks always bite back later
on.
Well, why is broken-wp more accurate than wp-inverted? Strictly
speaking the WP is there and working, it's just tied off to some value
you want to have interpreted the other way.
Anyway, seems like this is solvable with wp-inverted and whether the
additional quirk is needed I leave to others do decide.
I've begged for this patch - or a similar one - to be included too, because on
our boards, the "wp" value appears to be sort of random. Out of 5 prototype
boards, 3 would only boot with wp-inverted while the other 2 wouldn't boot
with wp-inverted set.
In our case I really don't know (and I don't care either) to which logic level
the wp happens to think it's wired. I just want to be able to tell the driver
that the WP line is
free-floating-and-might-have-any-random-value-at-any-given-moment which is a
bit long, so I'd go for disable-wp instead.
Mike.
Met vriendelijke groet / kind regards,
Mike Looijmans
TOPIC Embedded Systems
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