PM / devfreq: exynos: Use Use devm_clk_get_enabled() helpers

This macro has the advantage over SET_SYSTEM_SLEEP_PM_OPS that we don't have to care about when the functions are actually used.

Also make use of pm_sleep_ptr() to discard all PM_SLEEP related stuff if CONFIG_PM_SLEEP isn't enabled.

Signed-off-by Anand Moon <[email protected]>

---
v3: fix using new DEFINE_SIMPLE_DEV_PM_OPS PM macro hence
change the $subject and the commit message

v2: add __maybe_unused to suspend/resume functions in case CONFIG_PM
is disabled

---
 drivers/devfreq/exynos-bus.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

drivers/devfreq/exynos-bus.c +3 -7

index 153340b6685f..b89e04eb8430 100644
@@ -454,7 +454,6 @@ static void exynos_bus_shutdown(struct platform_device *pdev)
        devfreq_suspend_device(bus->devfreq);
 }
 
-#ifdef CONFIG_PM_SLEEP
 static int exynos_bus_resume(struct device *dev)
 {
        struct exynos_bus *bus = dev_get_drvdata(dev);

@@ -482,11 +481,9 @@ static int exynos_bus_suspend(struct device *dev)
 
        return 0;
 }
-#endif
 
-static const struct dev_pm_ops exynos_bus_pm = {
-       SET_SYSTEM_SLEEP_PM_OPS(exynos_bus_suspend, exynos_bus_resume)
-};
+static DEFINE_SIMPLE_DEV_PM_OPS(exynos_bus_pm,
+                               exynos_bus_suspend, exynos_bus_resume);
 
 static const struct of_device_id exynos_bus_of_match[] = {
        { .compatible = "samsung,exynos-bus", },

@@ -499,7 +496,7 @@ static struct platform_driver exynos_bus_platdrv = {
        .shutdown       = exynos_bus_shutdown,
        .driver = {
                .name   = "exynos-bus",
-               .pm     = &exynos_bus_pm,
+               .pm     = pm_sleep_ptr(&exynos_bus_pm),
                .of_match_table = exynos_bus_of_match,
        },
 };
--

2.44.0

The devm_clk_get_enabled() helpers:
- call devm_clk_get()
- call clk_prepare_enable() and register what is needed in order to call clk_disable_unprepare() when needed, as a managed resource.

This simplifies the code and avoids the calls to clk_disable_unprepare().

While at it, use dev_err_probe consistently, and use its return value to return the error code.

Signed-off-by Anand Moon <[email protected]>

---
v3 - No change
v2 - No change

---
 drivers/devfreq/exynos-bus.c | 21 ++++-----------------
 1 file changed, 4 insertions(+), 17 deletions(-)

drivers/devfreq/exynos-bus.c +0 -6

index 245898f1a88e..153340b6685f 100644
@@ -160,7 +160,6 @@ 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_token);
 }
 

@@ -171,7 +170,6 @@ 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);
 }
 
 static int exynos_bus_parent_parse_of(struct device_node *np,

@@ -247,23 +245,15 @@ static int exynos_bus_parse_of(struct device_node *np,
        int ret;
 
        /* Get the clock to provide each bus with source clock */
-       bus->clk = devm_clk_get(dev, "bus");
-       if (IS_ERR(bus->clk)) {
-               dev_err(dev, "failed to get bus clock\n");
-               return PTR_ERR(bus->clk);

drivers/devfreq/exynos-bus.c +1 -5

        /* Get the freq and voltage from OPP table to scale the bus freq */
        ret = dev_pm_opp_of_add_table(dev);
        if (ret < 0) {
                dev_err(dev, "failed to get OPP table\n");
-               goto err_clk;
+               return ret;
        }
 
        rate = clk_get_rate(bus->clk);

@@ -281,8 +271,6 @@ static int exynos_bus_parse_of(struct device_node *np,
 
 err_opp:
        dev_pm_opp_of_remove_table(dev);
-err_clk:
-       clk_disable_unprepare(bus->clk);
 
        return ret;
 }

@@ -453,7 +441,6 @@ static int exynos_bus_probe(struct platform_device *pdev)
 
 err:
        dev_pm_opp_of_remove_table(dev);
-       clk_disable_unprepare(bus->clk);
 err_reg:
        dev_pm_opp_put_regulators(bus->opp_token);
 
--

2.44.0

Quoted 47 lines · Anand Moon

The devm_clk_get_enabled() helpers:
- call devm_clk_get()
- call clk_prepare_enable() and register what is needed in order to call clk_disable_unprepare() when needed, as a managed resource.

This simplifies the code and avoids the calls to clk_disable_unprepare().

While at it, use dev_err_probe consistently, and use its return value to return the error code.

Signed-off-by Anand Moon <[email protected]>

---
v3 - No change
v2 - No change

---
 drivers/devfreq/exynos-bus.c | 21 ++++-----------------
 1 file changed, 4 insertions(+), 17 deletions(-)

drivers/devfreq/exynos-bus.c +0 -6

index 245898f1a88e..153340b6685f 100644
@@ -160,7 +160,6 @@ 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_token);
 }
 

@@ -171,7 +170,6 @@ 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);
 }
 
 static int exynos_bus_parent_parse_of(struct device_node *np,

@@ -247,23 +245,15 @@ static int exynos_bus_parse_of(struct device_node *np,
        int ret;
 
        /* Get the clock to provide each bus with source clock */
-       bus->clk = devm_clk_get(dev, "bus");
-       if (IS_ERR(bus->clk)) {
-               dev_err(dev, "failed to get bus clock\n");
-               return PTR_ERR(bus->clk);

drivers/devfreq/exynos-bus.c static int exynos_bus_parse_of(struct device_node *np, · line 250

Quoted 10 lines

drivers/devfreq/exynos-bus.c +3 -7

-       }
-
-       ret = clk_prepare_enable(bus->clk);
-       if (ret < 0) {
-               dev_err(dev, "failed to get enable clock\n");
-               return ret;
-       }
+       bus->clk = devm_clk_get_enabled(dev, "bus");
+       if (IS_ERR(bus->clk))
+               return dev_err_probe(dev, PTR_ERR(bus->clk), "failed to get bus clock\n");

nitpick. I recommend that better to keep 80 char on one line as following for the readability.

               return dev_err_probe(dev, PTR_ERR(bus->clk),
                                          "failed to get bus clock\n");