* Tomi Valkeinen <[email protected]> [150127 03:37]: > On 26/01/15 17:49, Tony Lindgren wrote: > > >> I'm not sure if I miss something, but regmap_write does not protect from > >> problems if there are multiple users for the same registers. You need to > >> use regmap_update_bits() to get a protected read/write sequence, in > >> which you can change only the bits that you want to change. > > > > To me it seems that issue can be fixed by making all the code use regmap. > > AFAIK that should work for the legacy code too. > > Even if everybody uses regmap, doing > > v = regmap_read() > modify v > regmap_write(v) > > is racy. regmap_update_bits() has to be used to protect the read/write > sequence. Which may be somewhat challenging at times with some strange > registers, the like Roger Q encountered recently related to CAN.
Yeah that's a good point. Regards, Tony -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
