On Wed, 19 Jun 2013 10:48:53 -0700 Dirk Brandewie <dirk.brandewie@xxxxxxxxx> wrote: > On 06/19/2013 10:12 AM, Lukasz Majewski wrote: > > This commit adds boost frequency support in cpufreq core (Hardware & > > > +/********************************************************************* > > * REGISTER / UNREGISTER CPUFREQ > > DRIVER * > > *********************************************************************/ > > > > @@ -1936,6 +2019,16 @@ int cpufreq_register_driver(struct > > cpufreq_driver *driver_data) cpufreq_driver = driver_data; > > write_unlock_irqrestore(&cpufreq_driver_lock, flags); > > > > + if (!cpufreq_driver->boost_supported) > > + boost.attr.mode = 0444; > > + > > + ret = cpufreq_sysfs_create_file(&(boost.attr)); > > + if (ret) { > > + pr_err("%s: cannot register global boost sysfs > > file\n", > > + __func__); > > + goto err_null_driver; > > + } > > + > > I do not think the boost sysfs should be created at all if boost is > not supported. This was my first thought. But unfortunately this "boost" attribute is always exported at acpi-cpufreq.c and in my opinion is part of a legacy API. I totally agree with the idea of exporting boost only when supported, but I would like to know the community opinion about this (especially Viresh and Rafael shall speak up). > > For intel_pstate the read-only boost would be there for no reason and > would cause confusion on the part of the user IMHO You are probably right here. However I don't know what was the original rationale behind exporting this attribute as read only. > > > ret = subsys_interface_register(&cpufreq_interface); > > if (ret) > > goto err_null_driver; > > @@ -1992,6 +2085,8 @@ int cpufreq_unregister_driver(struct > > cpufreq_driver *driver) pr_debug("unregistering driver %s\n", > > driver->name); > > > > subsys_interface_unregister(&cpufreq_interface); > > + > > + cpufreq_sysfs_remove_file(&(boost.attr)); > > unregister_hotcpu_notifier(&cpufreq_cpu_notifier); > > > Best regards, Lukasz Majewski -- 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