Re: [PATCH 0/3] libata: prevent writes to read-only registers

From: Tejun Heo
Date: Thu Jun 22 2017 - 16:13:30 EST

On Wed, Jun 21, 2017 at 04:20:11PM -0700, Doug Berger wrote:
> Recent Broadcom SoCs allow for the trapping of write accesses to
> read-only registers. This is only useful if such accesses are
> exceptional, so it is desirable to prevent such accesses in normal
> operation. To that end, this set of commits proposes adding two
> flags to the libata core.
> The first allows for a quirk that exists in some Broadcom devices
> that are capable of supporting Aggresive Link Power Management even
> though it is not reported by their read-only capability register.
> This removes a need for the Broadcom driver to write to it's
> read-only capability register.
> The second is a notification to the libata-core that it should not
> write to any standard registers that are defined to be read-only.
> The Broadcom driver is then modified to use these two general
> purpose flags.

Applied 1-3 to libata/for-4.13.