Re: [PATCH v2] cpufreq: exynos: Use simple approach to asses if cpu cooling can be used

Lukasz Majewski
2015-02-26T10:36:24Z

Hi Eduardo,

> Commit: e725d26c4857e5e41975b5e74e64ce6ab09a7121 provided possibility
> to use device tree to asses if cpu can be used as cooling device.
> Since the code was somewhat awkward, simpler approach has been
> proposed.
>
> Test HW: Exynos 4412 - Odroid U3.
>
> Suggested-by: Viresh Kumar <viresh.kumar@linaro.org>
> Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>

This patch is also missing from linux-thermal-soc tree.

I will add it to samsung thermal tree, since Viresh has ACK'ed it.

> ---
> Changes for v2:
> - Remove superfluous *np pointer
> ---
> drivers/cpufreq/exynos-cpufreq.c | 21 ++++++---------------
> 1 file changed, 6 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/cpufreq/exynos-cpufreq.c
> b/drivers/cpufreq/exynos-cpufreq.c index 5e98c6b..82d2fbb 100644
> --- a/drivers/cpufreq/exynos-cpufreq.c
> +++ b/drivers/cpufreq/exynos-cpufreq.c
> @@ -159,7 +159,7 @@ static struct cpufreq_driver exynos_driver = {
>
> static int exynos_cpufreq_probe(struct platform_device *pdev)
> {
> - struct device_node *cpus, *np;
> + struct device_node *cpu0;
> int ret = -EINVAL;
>
> exynos_info = kzalloc(sizeof(*exynos_info), GFP_KERNEL);
> @@ -206,28 +206,19 @@ static int exynos_cpufreq_probe(struct
> platform_device *pdev) if (ret)
> goto err_cpufreq_reg;
>
> - cpus = of_find_node_by_path("/cpus");
> - if (!cpus) {
> - pr_err("failed to find cpus node\n");
> + cpu0 = of_get_cpu_node(0, NULL);
> + if (!cpu0) {
> + pr_err("failed to find cpu0 node\n");
> return 0;
> }
>
> - np = of_get_next_child(cpus, NULL);
> - if (!np) {
> - pr_err("failed to find cpus child node\n");
> - of_node_put(cpus);
> - return 0;
> - }
> -
> - if (of_find_property(np, "#cooling-cells", NULL)) {
> - cdev = of_cpufreq_cooling_register(np,
> + if (of_find_property(cpu0, "#cooling-cells", NULL)) {
> + cdev = of_cpufreq_cooling_register(cpu0,
> cpu_present_mask);
> if (IS_ERR(cdev))
> pr_err("running cpufreq without cooling
> device: %ld\n", PTR_ERR(cdev));
> }
> - of_node_put(np);
> - of_node_put(cpus);
>
> return 0;
>

--
Best regards,

Lukasz Majewski

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