Re: Linux 2.4.17 bug, mmap of /dev/mem

In message [ref] you wrote:

memory spaces.  A common mistake is people map things like GPIO into
application space, and then think they can atomically update the
registers.  This doesnt' work because there may be drivers that
also do the same thing.

...and things get even worse when you happen to use the  RISC  timers
for  one  or  more  PWM  channels: you'll see completely asynchronous
updates of PBDAT :-(

Wolfgang Denk

--
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: wd@denx.de
"Engineering without management is art."               - Jeff Johnson

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