Re: [PATCH V2 11/16] cpufreq: dt: Pass regulator name to the OPP core

From: Stephen Boyd
Date: Mon Feb 01 2016 - 21:34:23 EST


On 01/28, Viresh Kumar wrote:
> @@ -119,6 +120,49 @@ static int set_target(struct cpufreq_policy *policy, unsigned int index)
> return ret;
> }
>
> +/*
> + * An earlier version of opp-v1 bindings used to name the regulator
> + * "cpu0-supply", we still need to handle that for backwards compatibility.
> + */
> +static const char *find_supply_name(struct device *dev)
> +{
> + struct regulator *cpu_reg;
> + char *reg_cpu0 = "cpu0", *reg_cpu = "cpu", *reg;
> + int cpu = dev->id, ret;
> +
> + /* Try "cpu0" for older DTs */
> + if (!cpu)
> + reg = reg_cpu0;
> + else
> + reg = reg_cpu;
> +
> +try_again:
> + cpu_reg = regulator_get_optional(dev, reg);
> + ret = PTR_ERR_OR_ZERO(cpu_reg);
> + if (!ret) {
> + regulator_put(cpu_reg);

What's the point of creating a regulator just to find the name?
It seems like we should just look in the DT node of the CPU for
cpu-supply vs cpu0-supply. Then we don't need to involve the
regulator framework at all.

> + return reg;
> + }
> +
> + /*
> + * If cpu's regulator supply node is present, but regulator is not yet
> + * registered, we should try defering probe.
> + */
> + if (ret == -EPROBE_DEFER) {
> + dev_dbg(dev, "cpu%d regulator not ready, retry\n", cpu);
> + return ERR_PTR(ret);
> + }
> +
> + /* Try with "cpu-supply" */
> + if (reg == reg_cpu0) {
> + reg = reg_cpu;
> + goto try_again;
> + }
> +
> + dev_dbg(dev, "no regulator for cpu%d: %d\n", cpu, ret);
> + return NULL;
> +}
> +
> static int allocate_resources(int cpu, struct device **cdev,
> struct regulator **creg, struct clk **cclk)
> {
> @@ -383,6 +450,9 @@ static int cpufreq_exit(struct cpufreq_policy *policy)
> cpufreq_cooling_unregister(priv->cdev);
> dev_pm_opp_free_cpufreq_table(priv->cpu_dev, &policy->freq_table);
> dev_pm_opp_of_cpumask_remove_table(policy->related_cpus);
> + if (priv->reg_name)
> + dev_pm_opp_put_regulator(priv->cpu_dev);

Let's hope this goes away because it's always right next to
dev_pm_opp_of_cpumask_remove_table() anyway. Same for reg_name.

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