Re: [PATCH 3/4] rtc: s3c: use unified functions for enable/disable of clk

From: Krzysztof Kozlowski
Date: Tue Aug 11 2015 - 20:10:18 EST


On 11.08.2015 20:28, Joonyoung Shim wrote:
> The driver uses clk_prepare_enable()/clk_disable_unprepare() only in
> probe only, elsewhere, use the unified functions for enable/disable of
> clk, e.g. s3c_rtc_enable_clk() / s3c_rtc_disable_clk(), so it's better
> to use them for consistency of code.
>
> Signed-off-by: Joonyoung Shim <jy0922.shim@xxxxxxxxxxx>
> ---
> drivers/rtc/rtc-s3c.c | 14 +++++++++-----
> 1 file changed, 9 insertions(+), 5 deletions(-)

First of all - the code is larger (9 insertions, 5 deletion) so I have
doubts if this is better.

Second - this is not equivalent change. The s3c_rtc_enable_clk/disable
calls grab spin lock which is not necessary in probe.

Best regards,
Krzysztof

>
> diff --git a/drivers/rtc/rtc-s3c.c b/drivers/rtc/rtc-s3c.c
> index 44b2921..abe2a6d 100644
> --- a/drivers/rtc/rtc-s3c.c
> +++ b/drivers/rtc/rtc-s3c.c
> @@ -476,19 +476,21 @@ static int s3c_rtc_probe(struct platform_device *pdev)
> dev_err(&pdev->dev, "failed to find rtc clock\n");
> return PTR_ERR(info->rtc_clk);
> }
> - clk_prepare_enable(info->rtc_clk);
> + clk_prepare(info->rtc_clk);
>
> if (info->data->needs_src_clk) {
> info->rtc_src_clk = devm_clk_get(&pdev->dev, "rtc_src");
> if (IS_ERR(info->rtc_src_clk)) {
> dev_err(&pdev->dev,
> "failed to find rtc source clock\n");
> - clk_disable_unprepare(info->rtc_clk);
> + clk_unprepare(info->rtc_clk);
> return PTR_ERR(info->rtc_src_clk);
> }
> - clk_prepare_enable(info->rtc_src_clk);
> + clk_prepare(info->rtc_src_clk);
> }
>
> + s3c_rtc_enable_clk(info);
> +
> /* check to see if everything is setup correctly */
> if (info->data->enable)
> info->data->enable(info);
> @@ -548,9 +550,11 @@ static int s3c_rtc_probe(struct platform_device *pdev)
> if (info->data->disable)
> info->data->disable(info);
>
> + s3c_rtc_disable_clk(info);
> +
> if (info->data->needs_src_clk)
> - clk_disable_unprepare(info->rtc_src_clk);
> - clk_disable_unprepare(info->rtc_clk);
> + clk_unprepare(info->rtc_src_clk);
> + clk_unprepare(info->rtc_clk);
>
> return ret;
> }
>

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