[PATCH 1/2] hwspinlock/omap: enable module before reading SYSSTATUS register

Ohad Ben-Cohen ohad at wizery.com
Thu Jul 24 06:45:44 PDT 2014

Hi Suman,

On Thu, Jul 3, 2014 at 2:00 AM, Suman Anna <s-anna at ti.com> wrote:
> The number of hwspinlocks are determined based on the value read
> from the IP block's SYSSTATUS register. However, the module may
> not be enabled and clocked, and the read may result in a bus error.
> This particular issue is seen rather easily on AM33XX, since the
> module wakeup is software controlled, and it is disabled out of
> reset. Make sure the module is enabled and clocked before reading
> the SYSSTATUS register.
> Signed-off-by: Suman Anna <s-anna at ti.com>
> +       /*
> +        * runtime PM will make sure the clock of this module is
> +        * enabled again iff at least one lock is requested
> +        */
> +       ret = pm_runtime_put_sync(&pdev->dev);

Is there a specific reason for using the put_sync variant here? If
not, let's just use the regular put().

Let me know, and I can do the change while applying these two patches.


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