Hi Kamil, On 19. 7. 20. 오전 12:05, [email protected] wrote: > Regulators should be enabled before clocks to avoid h/w hang. This > require change in exynos_bus_probe() to move exynos_bus_parse_of() > after exynos_bus_parent_parse_of() and change in enabling sequence > of regulator and clock in exynos_bus_parse_of(). Similar change is > needed in exynos_bus_exit() where clock should be disabled first. > > Signed-off-by: Kamil Konieczny <[email protected]> > --- > This patch is new to this series. > > --- > drivers/devfreq/exynos-bus.c | 58 ++++++++++++++++++++---------------- > 1 file changed, 32 insertions(+), 26 deletions(-) > > diff --git a/drivers/devfreq/exynos-bus.c b/drivers/devfreq/exynos-bus.c > index 486cc5b422f1..f391044aa39d 100644 > --- a/drivers/devfreq/exynos-bus.c > +++ b/drivers/devfreq/exynos-bus.c > @@ -194,11 +194,11 @@ static void exynos_bus_exit(struct device *dev) > if (ret < 0) > dev_warn(dev, "failed to disable the devfreq-event devices\n"); > > + clk_disable_unprepare(bus->clk); > if (bus->regulator) > regulator_disable(bus->regulator); > > dev_pm_opp_of_remove_table(dev); > - clk_disable_unprepare(bus->clk); > } > > /* > @@ -326,8 +326,7 @@ static int exynos_bus_parent_parse_of(struct device_node > *np, > return ret; > } > > -static int exynos_bus_parse_of(struct device_node *np, > - struct exynos_bus *bus) > +static int exynos_bus_parse_of(struct exynos_bus *bus) > { > struct device *dev = bus->dev; > struct dev_pm_opp *opp; > @@ -341,36 +340,35 @@ static int exynos_bus_parse_of(struct device_node *np, > return PTR_ERR(bus->clk); > } > > - ret = clk_prepare_enable(bus->clk); > + /* 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 enable clock\n"); > + dev_err(dev, "failed to get OPP table\n"); > return ret; > } > > - /* Get the freq and voltage from OPP table to scale the bus freq */ > - ret = dev_pm_opp_of_add_table(dev); > + ret = clk_prepare_enable(bus->clk); > if (ret < 0) { > - dev_err(dev, "failed to get OPP table\n"); > + dev_err(dev, "failed to enable clock\n"); > goto err_clk; > } > - > rate = clk_get_rate(bus->clk); > > opp = devfreq_recommended_opp(dev, &rate, 0); > if (IS_ERR(opp)) { > dev_err(dev, "failed to find dev_pm_opp\n"); > ret = PTR_ERR(opp); > - goto err_opp; > + goto err; > } > 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: > +err: > clk_disable_unprepare(bus->clk); > +err_clk: > + dev_pm_opp_of_remove_table(dev); > > return ret; > } > @@ -386,6 +384,7 @@ static int exynos_bus_probe(struct platform_device *pdev) > struct exynos_bus *bus; > int ret, max_state; > unsigned long min_freq, max_freq; > + bool passive = false; > > if (!np) { > dev_err(dev, "failed to find devicetree node\n"); > @@ -399,27 +398,31 @@ static int exynos_bus_probe(struct platform_device > *pdev) > bus->dev = &pdev->dev; > platform_set_drvdata(pdev, bus); > > - /* Parse the device-tree to get the resource information */ > - ret = exynos_bus_parse_of(np, bus); > - if (ret < 0) > - return ret; > - > profile = devm_kzalloc(dev, sizeof(*profile), GFP_KERNEL); > - if (!profile) { > - ret = -ENOMEM; > - goto err; > - } > + if (!profile) > + return -ENOMEM; > > node = of_parse_phandle(dev->of_node, "devfreq", 0); > if (node) { > of_node_put(node); > - goto passive; > + passive = true; > } else { > ret = exynos_bus_parent_parse_of(np, bus); > + if (ret < 0) > + return ret; > } > > - if (ret < 0) > - goto err; > + /* Parse the device-tree to get the resource information */ > + ret = exynos_bus_parse_of(bus); > + if (ret < 0) { > + if (!passive) > + regulator_disable(bus->regulator); > + > + return ret; > + } > + > + if (passive) > + goto passive; > > /* Initialize the struct profile and governor data for parent device */ > profile->polling_ms = 50; > @@ -508,8 +511,11 @@ static int exynos_bus_probe(struct platform_device *pdev) > return 0; > > err: > - dev_pm_opp_of_remove_table(dev); > clk_disable_unprepare(bus->clk); > + if (!passive) > + regulator_disable(bus->regulator); > + > + dev_pm_opp_of_remove_table(dev); > > return ret; > } >
Acked-by: Chanwoo Choi <[email protected]> -- Best Regards, Chanwoo Choi Samsung Electronics
