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

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.