On Sun, Jan 3, 2021 at 12:59 PM Yangtao Li <tiny.windzz@xxxxxxxxx> wrote:
>
> Use devm_pm_opp_* API to simplify code, and remove opp_table
> from exynos_bus.
>
> Signed-off-by: Yangtao Li <tiny.windzz@xxxxxxxxx>
> ---
> drivers/devfreq/exynos-bus.c | 42 ++++++++----------------------------
> 1 file changed, 9 insertions(+), 33 deletions(-)
>
> diff --git a/drivers/devfreq/exynos-bus.c b/drivers/devfreq/exynos-bus.c
> index e689101abc93..51752e5ce980 100644
> --- a/drivers/devfreq/exynos-bus.c
> +++ b/drivers/devfreq/exynos-bus.c
> @@ -33,7 +33,6 @@ struct exynos_bus {
>
> unsigned long curr_freq;
>
> - struct opp_table *opp_table;
> struct clk *clk;
> unsigned int ratio;
> };
> @@ -159,10 +158,7 @@ static void exynos_bus_exit(struct device *dev)
>
> platform_device_unregister(bus->icc_pdev);
>
> - dev_pm_opp_of_remove_table(dev);
> clk_disable_unprepare(bus->clk);
> - dev_pm_opp_put_regulators(bus->opp_table);
OPP uses the clock and regulator. It means that there are dependency
between them and the sequence for resource free.
I think that OPP should be removed before clock and regulator.
Your patch always guarantee this dependency? If not, we have to
free the resource according to the dependency.
> - bus->opp_table = NULL;
> }
>
> static void exynos_bus_passive_exit(struct device *dev)
> @@ -171,7 +167,6 @@ static void exynos_bus_passive_exit(struct device *dev)
>
> platform_device_unregister(bus->icc_pdev);
>
> - dev_pm_opp_of_remove_table(dev);
> clk_disable_unprepare(bus->clk);
> }
>
> @@ -183,15 +178,13 @@ static int exynos_bus_parent_parse_of(struct device_node *np,
> const char *vdd = "vdd";
> int i, ret, count, size;
>
> - opp_table = dev_pm_opp_set_regulators(dev, &vdd, 1);
> + opp_table = devm_pm_opp_set_regulators(dev, &vdd, 1);
> if (IS_ERR(opp_table)) {
> ret = PTR_ERR(opp_table);
> dev_err(dev, "failed to set regulators %d\n", ret);
> return ret;
> }
>
> - bus->opp_table = opp_table;
> -
> /*
> * Get the devfreq-event devices to get the current utilization of
> * buses. This raw data will be used in devfreq ondemand governor.
> @@ -199,25 +192,20 @@ static int exynos_bus_parent_parse_of(struct device_node *np,
> count = devfreq_event_get_edev_count(dev, "devfreq-events");
> if (count < 0) {
> dev_err(dev, "failed to get the count of devfreq-event dev\n");
> - ret = count;
> - goto err_regulator;
> + return count;
> }
> bus->edev_count = count;
>
> size = sizeof(*bus->edev) * count;
> bus->edev = devm_kzalloc(dev, size, GFP_KERNEL);
> - if (!bus->edev) {
> - ret = -ENOMEM;
> - goto err_regulator;
> - }
> + if (!bus->edev)
> + return -ENOMEM;
>
> for (i = 0; i < count; i++) {
> bus->edev[i] = devfreq_event_get_edev_by_phandle(dev,
> "devfreq-events", i);
> - if (IS_ERR(bus->edev[i])) {
> - ret = -EPROBE_DEFER;
> - goto err_regulator;
> - }
> + if (IS_ERR(bus->edev[i]))
> + return -EPROBE_DEFER;
> }
>
> /*
> @@ -234,12 +222,6 @@ static int exynos_bus_parent_parse_of(struct device_node *np,
> bus->ratio = DEFAULT_SATURATION_RATIO;
>
> return 0;
> -
> -err_regulator:
> - dev_pm_opp_put_regulators(bus->opp_table);
> - bus->opp_table = NULL;
> -
> - return ret;
> }
>
> static int exynos_bus_parse_of(struct device_node *np,
> @@ -264,7 +246,7 @@ static int exynos_bus_parse_of(struct device_node *np,
> }
>
> /* Get the freq and voltage from OPP table to scale the bus freq */
> - ret = dev_pm_opp_of_add_table(dev);
> + ret = devm_pm_opp_of_add_table(dev);
> if (ret < 0) {
> dev_err(dev, "failed to get OPP table\n");
> goto err_clk;
> @@ -276,15 +258,13 @@ static int exynos_bus_parse_of(struct device_node *np,
> if (IS_ERR(opp)) {
> dev_err(dev, "failed to find dev_pm_opp\n");
> ret = PTR_ERR(opp);
> - goto err_opp;
> + goto err_clk;
> }
> bus->curr_freq = dev_pm_opp_get_freq(opp);
> dev_pm_opp_put(opp);
>
> return 0;
>
> -err_opp:
> - dev_pm_opp_of_remove_table(dev);
> err_clk:
> clk_disable_unprepare(bus->clk);
>
> @@ -425,7 +405,7 @@ static int exynos_bus_probe(struct platform_device *pdev)
> /* Parse the device-tree to get the resource information */
> ret = exynos_bus_parse_of(np, bus);
> if (ret < 0)
> - goto err_reg;
> + return ret;
>
> if (passive)
> ret = exynos_bus_profile_init_passive(bus, profile);
> @@ -456,11 +436,7 @@ static int exynos_bus_probe(struct platform_device *pdev)
> return 0;
>
> err:
> - dev_pm_opp_of_remove_table(dev);
> clk_disable_unprepare(bus->clk);
> -err_reg:
> - dev_pm_opp_put_regulators(bus->opp_table);
> - bus->opp_table = NULL;
>
> return ret;
> }
> --
> 2.25.1
>
--
Best Regards,
Chanwoo Choi
