Re: [PATCH] iio: adc: stm32-adc: Remove redundant null check before clk_prepare_enable/clk_disable_unprepare

Fabrice Gasnier
2020-12-18T14:34:17Z

On 12/18/20 10:35 AM, Xu Wang wrote:
> Because clk_prepare_enable() and clk_disable_unprepare() already checked
> NULL clock parameter, so the additional checks are unnecessary, just
> remove them.
>
> Signed-off-by: Xu Wang <vulab@iscas.ac.cn>
> ---
> drivers/iio/adc/stm32-adc-core.c | 29 +++++++++++------------------
> drivers/iio/adc/stm32-adc.c | 14 +++++---------
> 2 files changed, 16 insertions(+), 27 deletions(-)

Hi Xu,

Acked-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>

Thanks for your patch,
Best Regards,
Fabrice

>
> diff --git a/drivers/iio/adc/stm32-adc-core.c b/drivers/iio/adc/stm32-adc-core.c
> index 9d1ad6e38e85..c088cb990193 100644
> --- a/drivers/iio/adc/stm32-adc-core.c
> +++ b/drivers/iio/adc/stm32-adc-core.c
> @@ -535,20 +535,16 @@ static int stm32_adc_core_hw_start(struct device *dev)
> goto err_switches_dis;
> }
>
> - if (priv->bclk) {
> - ret = clk_prepare_enable(priv->bclk);
> - if (ret < 0) {
> - dev_err(dev, "bus clk enable failed\n");
> - goto err_regulator_disable;
> - }
> + ret = clk_prepare_enable(priv->bclk);
> + if (ret < 0) {
> + dev_err(dev, "bus clk enable failed\n");
> + goto err_regulator_disable;
> }
>
> - if (priv->aclk) {
> - ret = clk_prepare_enable(priv->aclk);
> - if (ret < 0) {
> - dev_err(dev, "adc clk enable failed\n");
> - goto err_bclk_disable;
> - }
> + ret = clk_prepare_enable(priv->aclk);
> + if (ret < 0) {
> + dev_err(dev, "adc clk enable failed\n");
> + goto err_bclk_disable;
> }
>
> writel_relaxed(priv->ccr_bak, priv->common.base + priv->cfg->regs->ccr);
> @@ -556,8 +552,7 @@ static int stm32_adc_core_hw_start(struct device *dev)
> return 0;
>
> err_bclk_disable:
> - if (priv->bclk)
> - clk_disable_unprepare(priv->bclk);
> + clk_disable_unprepare(priv->bclk);
> err_regulator_disable:
> regulator_disable(priv->vref);
> err_switches_dis:
> @@ -575,10 +570,8 @@ static void stm32_adc_core_hw_stop(struct device *dev)
>
> /* Backup CCR that may be lost (depends on power state to achieve) */
> priv->ccr_bak = readl_relaxed(priv->common.base + priv->cfg->regs->ccr);
> - if (priv->aclk)
> - clk_disable_unprepare(priv->aclk);
> - if (priv->bclk)
> - clk_disable_unprepare(priv->bclk);
> + clk_disable_unprepare(priv->aclk);
> + clk_disable_unprepare(priv->bclk);
> regulator_disable(priv->vref);
> stm32_adc_core_switches_supply_dis(priv);
> regulator_disable(priv->vdda);
> diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c
> index c067c994dae2..f7c53cea509a 100644
> --- a/drivers/iio/adc/stm32-adc.c
> +++ b/drivers/iio/adc/stm32-adc.c
> @@ -546,8 +546,7 @@ static int stm32_adc_hw_stop(struct device *dev)
> if (adc->cfg->unprepare)
> adc->cfg->unprepare(indio_dev);
>
> - if (adc->clk)
> - clk_disable_unprepare(adc->clk);
> + clk_disable_unprepare(adc->clk);
>
> return 0;
> }
> @@ -558,11 +557,9 @@ static int stm32_adc_hw_start(struct device *dev)
> struct stm32_adc *adc = iio_priv(indio_dev);
> int ret;
>
> - if (adc->clk) {
> - ret = clk_prepare_enable(adc->clk);
> - if (ret)
> - return ret;
> - }
> + ret = clk_prepare_enable(adc->clk);
> + if (ret)
> + return ret;
>
> stm32_adc_set_res(adc);
>
> @@ -575,8 +572,7 @@ static int stm32_adc_hw_start(struct device *dev)
> return 0;
>
> err_clk_dis:
> - if (adc->clk)
> - clk_disable_unprepare(adc->clk);
> + clk_disable_unprepare(adc->clk);
>
> return ret;
> }
>