[PATCH v4] cpufreq: powerpc: Add cpufreq driver for Freescale e500mc SoCs

Viresh Kumar viresh.kumar at linaro.org
Tue Apr 9 19:47:11 EST 2013


Mostly good now, V5 should be the final one.

On 9 April 2013 14:02,  <Yuantian.Tang at freescale.com> wrote:
> diff --git a/drivers/cpufreq/ppc-corenet-cpufreq.c b/drivers/cpufreq/ppc-corenet-cpufreq.c

> +static int corenet_cpufreq_target(struct cpufreq_policy *policy,
> +               unsigned int target_freq, unsigned int relation)
> +{
> +       struct cpufreq_freqs freqs;
> +       unsigned int new;
> +       struct clk *parent;
> +       int ret;
> +       struct cpu_data *data = per_cpu(cpu_data, policy->cpu);
> +
> +       cpufreq_frequency_table_target(policy, data->table,
> +                       target_freq, relation, &new);
> +
> +       if (policy->cur == data->table[new].frequency)
> +               return 0;
> +
> +       freqs.old = policy->cur;
> +       freqs.new = data->table[new].frequency;
> +       freqs.cpu = policy->cpu;

You don't need to set freqs.cpu..

> +       mutex_lock(&cpufreq_lock);
> +       cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE);
> +
> +       parent = of_clk_get(data->parent, new);
> +       ret = clk_set_parent(data->clk, parent);
> +       if (ret) {
> +               freqs.new = freqs.old;
> +               cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE);
> +               mutex_unlock(&cpufreq_lock);
> +               return ret;
> +       }
> +
> +       cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE);
> +       mutex_unlock(&cpufreq_lock);

What about writing it as:

+       ret = clk_set_parent(data->clk, parent);
+       if (ret)
+               freqs.new = freqs.old;
+
+       cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE);
+       mutex_unlock(&cpufreq_lock);

return ret;

> +       return 0;
> +}


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