On Thu, May 21, 2020 at 5:06 PM Weiyi Lu <weiyi.lu@xxxxxxxxxxxx> wrote:
>
> For the bus protection operations, some subsys clocks need to be enabled
> before releasing the protection, and vice versa.
> But those subsys clocks could only be controlled once its corresponding
> power domain is turned on first.
> In this patch, we add the subsys clock control into its relevant steps.
>
> Signed-off-by: Weiyi Lu <weiyi.lu@xxxxxxxxxxxx>
> ---
> drivers/soc/mediatek/mtk-scpsys.c | 62 +++++++++++++++++++++++++++++++++++++--
> 1 file changed, 60 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/soc/mediatek/mtk-scpsys.c b/drivers/soc/mediatek/mtk-scpsys.c
> index 59a525a..ef2c668 100644
> --- a/drivers/soc/mediatek/mtk-scpsys.c
> +++ b/drivers/soc/mediatek/mtk-scpsys.c
> [snip]
> val |= PWR_ISO_BIT;
> @@ -498,6 +511,39 @@ static int scpsys_power_off(struct generic_pm_domain *genpd)
> return ret;
> }
>
> +static int init_subsys_clks(struct platform_device *pdev,
> + const char *prefix, struct clk **clk)
> +{
> + struct device_node *node = pdev->dev.of_node;
> + u32 prefix_len, sub_clk_cnt = 0;
> + struct property *prop;
> + const char *clk_name;
> +
> + prefix_len = strlen(prefix);
> +
> + of_property_for_each_string(node, "clock-names", prop, clk_name) {
> + if (!strncmp(clk_name, prefix, prefix_len) &&
> + (clk_name[prefix_len] == '-')) {
> + if (sub_clk_cnt >= MAX_SUBSYS_CLKS) {
> + dev_err(&pdev->dev,
> + "subsys clk out of range %d\n",
> + sub_clk_cnt);
> + return -EINVAL;
> + }
> +
> + clk[sub_clk_cnt] = devm_clk_get(&pdev->dev,
> + clk_name);
> +
> + if (IS_ERR(clk[sub_clk_cnt]))
> + return PTR_ERR(clk[sub_clk_cnt]);
> +
> + sub_clk_cnt++;
> + }
> + }
> +
> + return sub_clk_cnt;
> +}
> +
> static int init_basic_clks(struct platform_device *pdev, struct clk **clk,
> const char * const *name)
> {
> @@ -596,6 +642,18 @@ static struct scp *init_scp(struct platform_device *pdev,
> if (ret)
> return ERR_PTR(ret);
>
> + if (data->subsys_clk_prefix) {
> + ret = init_subsys_clks(pdev,
> + data->subsys_clk_prefix,
> + scpd->subsys_clk);
> + if (ret < 0) {
> + dev_err(&pdev->dev,
> + "%s: subsys clk unavailable\n",
> + data->name);
init_subsys_clks should already have printed an error (directly or
indirectly), so this is not needed.
> + return ERR_PTR(ret);
> + }
> + }
> +
> genpd->name = data->name;
> genpd->power_off = scpsys_power_off;
> genpd->power_on = scpsys_power_on;
> --
> 1.8.1.1.dirty
