On Tue, Jun 18, 2013 at 5:11 PM, Russell King - ARM Linux <linux@xxxxxxxxxxxxxxxx> wrote: > On Tue, Jun 18, 2013 at 05:02:49PM +0200, Linus Walleij wrote: >> Nowadays I would do the above with regmap_update_bits(). >> >> Mutual exclusion for read-modify-write of individual bits in a >> register is one of those cases where doing a regmap over >> a memory-mapped register range makes a lot of sense. >> (drivers/mfd/syscon.c being a nice example) > > So, for that solution we need to have some kind of global regmap per > register or somesuch. Then you run into regmap needing a struct > device - well, with a shared register, which struct device do you > use, or do you have to invent one? Usually, like for syscon, you create an MFD hub which carry the regmap. > That sounds more heavy-weight than is really necessary. May be so, especially if there is just one register to protect. The usefulness of MM-regmap increase with the set of registers needing to be protected. Yours, Linus Walleij -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
