Re: [PATCH 5/8] thermal:cpu cooling:tegra: Provide deferred probing for tegra driver

Mikko Perttunen
2014-11-14T10:47:48Z

Tested-by: Mikko Perttunen <mikko.perttunen@kapsi.fi>

One potential issue I can see is that if the cpufreq driver fails to
probe then you'll never get the thermal driver either. For example,
Tegra124 currently has no cpufreq driver, so if CONFIG_CPU_THERMAL was
enabled, then the soctherm driver would never be able to probe. But I
don't really have a solution for this either.

Cheers,
Mikko

On 11/13/2014 07:02 PM, Lukasz Majewski wrote:
> When CPU freq is used as a thermal zone cooling device, one needs to wait
> until cpufreq subsystem is properly initialized.
>
> This code is similar to the one already available in imx_thermal.c file.
>
> Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
> ---
> drivers/thermal/tegra_soctherm.c | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/drivers/thermal/tegra_soctherm.c b/drivers/thermal/tegra_soctherm.c
> index 70f7e9e..9c5aaa4 100644
> --- a/drivers/thermal/tegra_soctherm.c
> +++ b/drivers/thermal/tegra_soctherm.c
> @@ -26,6 +26,7 @@
> #include <linux/platform_device.h>
> #include <linux/reset.h>
> #include <linux/thermal.h>
> +#include <linux/cpufreq.h>
>
> #include <soc/tegra/fuse.h>
>
> @@ -346,6 +347,12 @@ static int tegra_soctherm_probe(struct platform_device *pdev)
>
> const struct tegra_tsensor *tsensors = t124_tsensors;
>
> +#ifdef CONFIG_CPU_THERMAL
> + if (!cpufreq_get_current_driver()) {
> + dev_dbg(&pdev->dev, "no cpufreq driver!");
> + return -EPROBE_DEFER;
> + }
> +#endif
> tegra = devm_kzalloc(&pdev->dev, sizeof(*tegra), GFP_KERNEL);
> if (!tegra)
> return -ENOMEM;
>