On Saturday, January 26, 2013 09:55:50 PM Shawn Guo wrote: > As multiplatform build is being adopted by more and more ARM platforms, > initcall function should be used very carefully. For example, when > GENERIC_CPUFREQ_CPU0 is built in the kernel, cpu0_cpufreq_driver_init() > will be called on all the platforms to initialize cpufreq-cpu0 driver. > > To eliminate this undesired the effect, the patch changes cpufreq-cpu0 > driver to have it instantiated as a platform_driver. Then it will only > run on platforms that create the platform_device "cpufreq-cpu0". > > Along with the change, it also changes cpu_dev to be &pdev->dev, > so that managed functions can start working, and module build gets > supported too. > > Signed-off-by: Shawn Guo <shawn.guo@xxxxxxxxxx> > --- > Rafael, > > The patch depends patch "power: export opp cpufreq functions". > https://patchwork.kernel.org/patch/1847261/ That one should use EXPORT_SYMBOL_GPL() for exporting symbols, though. Care to add a fixed version to the patch set along with the $subject one? > AnilKumar, > > Unfortunately, the change will require some platform level adoption > to have cpufreq-cpu0 driver continue working for am33xx. But it should > be as simple as something like below. > > struct platform_device_info devinfo = { .name = "cpufreq-cpu0", }; > platform_device_register_full(&devinfo); That should be included in your patch, then. Thanks, Rafael > drivers/cpufreq/Kconfig | 2 +- > drivers/cpufreq/cpufreq-cpu0.c | 35 +++++++++++++++++++++++------------ > 2 files changed, 24 insertions(+), 13 deletions(-) > > diff --git a/drivers/cpufreq/Kconfig b/drivers/cpufreq/Kconfig > index ea512f4..774dc1c 100644 > --- a/drivers/cpufreq/Kconfig > +++ b/drivers/cpufreq/Kconfig > @@ -180,7 +180,7 @@ config CPU_FREQ_GOV_CONSERVATIVE > If in doubt, say N. > > config GENERIC_CPUFREQ_CPU0 > - bool "Generic CPU0 cpufreq driver" > + tristate "Generic CPU0 cpufreq driver" > depends on HAVE_CLK && REGULATOR && PM_OPP && OF > select CPU_FREQ_TABLE > help > diff --git a/drivers/cpufreq/cpufreq-cpu0.c b/drivers/cpufreq/cpufreq-cpu0.c > index debc5a7..dae0667 100644 > --- a/drivers/cpufreq/cpufreq-cpu0.c > +++ b/drivers/cpufreq/cpufreq-cpu0.c > @@ -12,12 +12,12 @@ > #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt > > #include <linux/clk.h> > -#include <linux/cpu.h> > #include <linux/cpufreq.h> > #include <linux/err.h> > #include <linux/module.h> > #include <linux/of.h> > #include <linux/opp.h> > +#include <linux/platform_device.h> > #include <linux/regulator/consumer.h> > #include <linux/slab.h> > > @@ -177,7 +177,7 @@ static struct cpufreq_driver cpu0_cpufreq_driver = { > .attr = cpu0_cpufreq_attr, > }; > > -static int cpu0_cpufreq_driver_init(void) > +static int cpu0_cpufreq_probe(struct platform_device *pdev) > { > struct device_node *np; > int ret; > @@ -188,23 +188,17 @@ static int cpu0_cpufreq_driver_init(void) > return -ENOENT; > } > > - cpu_dev = get_cpu_device(0); > - if (!cpu_dev) { > - pr_err("failed to get cpu0 device\n"); > - ret = -ENODEV; > - goto out_put_node; > - } > - > + cpu_dev = &pdev->dev; > cpu_dev->of_node = np; > > - cpu_clk = clk_get(cpu_dev, NULL); > + cpu_clk = devm_clk_get(cpu_dev, NULL); > if (IS_ERR(cpu_clk)) { > ret = PTR_ERR(cpu_clk); > pr_err("failed to get cpu0 clock: %d\n", ret); > goto out_put_node; > } > > - cpu_reg = regulator_get(cpu_dev, "cpu0"); > + cpu_reg = devm_regulator_get(cpu_dev, "cpu0"); > if (IS_ERR(cpu_reg)) { > pr_warn("failed to get cpu0 regulator\n"); > cpu_reg = NULL; > @@ -267,7 +261,24 @@ out_put_node: > of_node_put(np); > return ret; > } > -late_initcall(cpu0_cpufreq_driver_init); > + > +static int cpu0_cpufreq_remove(struct platform_device *pdev) > +{ > + cpufreq_unregister_driver(&cpu0_cpufreq_driver); > + opp_free_cpufreq_table(cpu_dev, &freq_table); > + > + return 0; > +} > + > +static struct platform_driver cpu0_cpufreq_platdrv = { > + .driver = { > + .name = "cpufreq-cpu0", > + .owner = THIS_MODULE, > + }, > + .probe = cpu0_cpufreq_probe, > + .remove = cpu0_cpufreq_remove, > +}; > +module_platform_driver(cpu0_cpufreq_platdrv); > > MODULE_AUTHOR("Shawn Guo <shawn.guo@xxxxxxxxxx>"); > MODULE_DESCRIPTION("Generic CPU0 cpufreq driver"); > -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- To unsubscribe from this list: send the line "unsubscribe cpufreq" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
