Re: [PATCH 4/4] devfreq: exynos4: Use SET_SYSTEM_SLEEP_PM_OPS macro instead of legacy method

From: Bartlomiej Zolnierkiewicz
Date: Wed Mar 12 2014 - 11:23:17 EST



Hi,

On Wednesday, March 12, 2014 08:48:02 PM Chanwoo Choi wrote:
> This patch use SET_SYSTEM_SLEEP_PM_OPS macro instead of legacy method. Also,
> Before entering suspend state, disable ppmu's clock to remove power-leakage
> in suspend state.

The main thing that this patch does is adding ->suspend method and PPMU
clocks handling and this should be reflected in the patch summary (i.e.
"devfreq: exynos4: fix PM suspend/resume handling for PPMU clocks") and in
the patch description. The fact that the patch also converts code to use
SET_SYSTEM_SLEEP_PM_OPS() macro is secondary.

> Signed-off-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
> ---
> drivers/devfreq/exynos/exynos4_bus.c | 26 +++++++++++++++++++++++++-
> 1 file changed, 25 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/devfreq/exynos/exynos4_bus.c b/drivers/devfreq/exynos/exynos4_bus.c
> index 0c5b99e..7e1540a 100644
> --- a/drivers/devfreq/exynos/exynos4_bus.c
> +++ b/drivers/devfreq/exynos/exynos4_bus.c
> @@ -1229,16 +1229,40 @@ static int exynos4_busfreq_remove(struct platform_device *pdev)
> return 0;
> }
>
> +#ifdef CONFIG_PM_SLEEP
> static int exynos4_busfreq_resume(struct device *dev)
> {
> struct busfreq_data *data = dev_get_drvdata(dev);
> + int i;
> +
> + /* Enable clock after wake-up from suspend state */
> + for (i = 0; i < PPMU_END; i++)
> + clk_prepare_enable(data->clk_ppmu[i]);
>
> + /* Reset PPMU to check utilization again */
> busfreq_mon_reset(data);
> +
> + return 0;
> +}
> +
> +static int exynos4_busfreq_suspend(struct device *dev)
> +{
> + struct busfreq_data *data = dev_get_drvdata(dev);
> + int i;
> +
> + /*
> + * Disable clock before entering suspend state
> + * to reduce leakage power on suspend state.
> + */
> + for (i = 0; i < PPMU_END; i++)
> + clk_disable_unprepare(data->clk_ppmu[i]);
> +
> return 0;
> }
> +#endif
>
> static const struct dev_pm_ops exynos4_busfreq_pm = {
> - .resume = exynos4_busfreq_resume,
> + SET_SYSTEM_SLEEP_PM_OPS(exynos4_busfreq_suspend, exynos4_busfreq_resume)
> };
>
> static const struct platform_device_id exynos4_busfreq_id[] = {

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/