Messages in this thread | | | Date | Fri, 28 Apr 2023 14:21:38 +0100 | From | Mark Brown <> | Subject | Re: [RFC PATCH] regmap: force update_bits() to write to HW when reg is volatile |
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On Fri, Apr 28, 2023 at 12:36:51PM +0000, Vaittinen, Matti wrote: > On 4/28/23 14:35, Mark Brown wrote:
> > I think you're looking for regmap_write_bits() here.
> Yes. Thanks for pointing this out to me. This is the functionality I > searched for.
> However, my question really was if the regmap_update_bits() (and > regmap_set_bits() / regmap_clear_bits()) should automatically work as > regmap_write_bits() for volatile registers. I'll take your answer as > "no" - and try to remember just use regmap_write_bits() with volatile > registers which may require forcing writing the value even when it is > not changed. Thanks!
Yeah, like you said in your commit there are cases where suppressing the write is still useful - you might have some bits that are volatile and some not or you might have something like a pattern where the hardware can set bits and the host writes 1 to clear. One common thing is to have read only status bits mixed in with normal read/write bits. [unhandled content-type:application/pgp-signature] | |