Re: [PATCH 07/10] opp: Add OPP sharing information to OPP library

Stephen Boyd
2015-07-20T17:46:30Z

On 07/17/2015 11:33 PM, Viresh Kumar wrote:
> From: Viresh Kumar <viresh.kumar@linaro.org>
> Date: Wed, 11 Feb 2015 16:16:28 +0800
> Subject: [PATCH] opp: Add OPP sharing information to OPP library
>
> An opp can be shared by multiple devices, for example its very common
> for CPUs to share the OPPs, i.e. when they share clock/voltage rails.
>
> This patch adds support of shared OPPs to the OPP library.
>
> Instead of a single device, dev_opp will not contain a list of devices
> that use it. It also senses if the device (we are trying to initialize
> OPPs for) shares OPPs with a device added earlier and in that case we
> update the list of devices managed by OPPs instead of duplicating OPPs
> again.
>
> The same infrastructure will be used for the old OPP bindings, with
> later patches.
>
> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>

> +static struct device_opp *_managed_opp(const struct device_node *np)
> +{
> + struct device_opp *dev_opp;
> +
> + list_for_each_entry_rcu(dev_opp, &dev_opp_list, node)
> + if (dev_opp->np == np) {
> + /*
> + * Multiple devices can point to the same OPP table and
> + * so will have same node-pointer, np.
> + *
> + * But the OPPs will be considered as shared only if the
> + * OPP table contains a "opp-shared" property.
> + */
> + if (dev_opp->shared_opp)
> + return dev_opp;
> + else
> + return NULL;
> +

The janitors will probably find this and say that it could be simplified
to an if () and a return without the else.

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