Re: [PATCH v5 06/14] soc: mediatek: Refactor clock control

From: Nicolas Boichat
Date: Tue Mar 19 2019 - 08:03:09 EST


On Tue, Mar 19, 2019 at 4:02 PM Weiyi Lu <weiyi.lu@xxxxxxxxxxxx> wrote:
>
> Put clock enable and disable control in separate function.
>
> Signed-off-by: Weiyi Lu <weiyi.lu@xxxxxxxxxxxx>
> ---
> drivers/soc/mediatek/mtk-scpsys.c | 49 ++++++++++++++++++++-----------
> 1 file changed, 32 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/soc/mediatek/mtk-scpsys.c b/drivers/soc/mediatek/mtk-scpsys.c
> index 765ad4a5e5df..3e9be07a2627 100644
> --- a/drivers/soc/mediatek/mtk-scpsys.c
> +++ b/drivers/soc/mediatek/mtk-scpsys.c
> @@ -208,6 +208,33 @@ static int scpsys_regulator_disable(struct scp_domain *scpd)
> return regulator_disable(scpd->supply);
> }
>
> +static int scpsys_clk_enable(struct clk *clk[], int max_num)
> +{
> + int i, ret = 0;
> +
> + for (i = 0; i < max_num && clk[i]; i++) {
> + ret = clk_prepare_enable(clk[i]);
> + if (ret) {
> + for (--i; i >= 0; i--)
> + clk_disable_unprepare(clk[i]);

Would it be simpler to just call scpsys_clk_disable(clk, i) ?

> +
> + break;
> + }
> + }
> +
> + return ret;
> +}

Maybe not for this series, but could you use clk_bulk_prepare_enable
instead? The only issue is that it'd still call clk_prepare_enable on
NULL clocks, but that does nothing, so it's just a little less
efficient...

> +
> +static void scpsys_clk_disable(struct clk *clk[], int max_num)
> +{
> + int i;
> +
> + for (i = max_num - 1; i >= 0; i--) {
> + if (clk[i])

if test not needed, clk_disable_unprepare ignores NULL parameters.

> + clk_disable_unprepare(clk[i]);
> + }
> +}

ditto: clk_bulk_disable_unprepare

> +
> static int scpsys_power_on(struct generic_pm_domain *genpd)
> {
> struct scp_domain *scpd = container_of(genpd, struct scp_domain, genpd);
> @@ -216,21 +243,14 @@ static int scpsys_power_on(struct generic_pm_domain *genpd)
> u32 pdn_ack = scpd->data->sram_pdn_ack_bits;
> u32 val;
> int ret, tmp;
> - int i;
>
> ret = scpsys_regulator_enable(scpd);
> if (ret < 0)
> return ret;
>
> - for (i = 0; i < MAX_CLKS && scpd->clk[i]; i++) {
> - ret = clk_prepare_enable(scpd->clk[i]);
> - if (ret) {
> - for (--i; i >= 0; i--)
> - clk_disable_unprepare(scpd->clk[i]);
> -
> - goto err_clk;
> - }
> - }
> + ret = scpsys_clk_enable(scpd->clk, MAX_CLKS);
> + if (ret)
> + goto err_clk;
>
> val = readl(ctl_addr);
> val |= PWR_ON_BIT;
> @@ -283,10 +303,7 @@ static int scpsys_power_on(struct generic_pm_domain *genpd)
> return 0;
>
> err_pwr_ack:
> - for (i = MAX_CLKS - 1; i >= 0; i--) {
> - if (scpd->clk[i])
> - clk_disable_unprepare(scpd->clk[i]);
> - }
> + scpsys_clk_disable(scpd->clk, MAX_CLKS);
> err_clk:
> scpsys_regulator_disable(scpd);
>
> @@ -303,7 +320,6 @@ static int scpsys_power_off(struct generic_pm_domain *genpd)
> u32 pdn_ack = scpd->data->sram_pdn_ack_bits;
> u32 val;
> int ret, tmp;
> - int i;
>
> if (scpd->data->bus_prot_mask) {
> ret = mtk_infracfg_set_bus_protection(scp->infracfg,
> @@ -344,8 +360,7 @@ static int scpsys_power_off(struct generic_pm_domain *genpd)
> if (ret < 0)
> goto out;
>
> - for (i = 0; i < MAX_CLKS && scpd->clk[i]; i++)
> - clk_disable_unprepare(scpd->clk[i]);
> + scpsys_clk_disable(scpd->clk, MAX_CLKS);
>
> ret = scpsys_regulator_disable(scpd);
> if (ret < 0)
> --
> 2.18.0
>