Messages in this thread | | | Date | Thu, 1 Mar 2012 11:30:32 +0000 | From | Mark Brown <> | Subject | Re: [PATCH v5 1/2] mfd: Add anatop mfd driver |
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On Thu, Mar 01, 2012 at 05:10:51PM +0800, Ying-Chun Liu (PaulLiu) wrote:
> + spin_lock(&adata->reglock); > + val = readl(adata->ioreg + addr); > + spin_unlock(&adata->reglock);
Do you really need to take a lock for a single read operation from a memory mapped register? I'd expect this to be atomic in itself. You need to lock on read/modify/write cycles to make sure that you don't get a read/read/modify/modify/write/write and misplace one of the modifies but that's not an issue for an isolated read. [unhandled content-type:application/pgp-signature] | |