kernel.git/drivers/base/power/opp, branch linux-4.13.y

PM / OPP: Call notifier without holding opp_table->lock

2017-10-05T07:47:35Z

commit e4d8ae00169f7686e1da5a62e5cf797d12bf8822 upstream. The notifier callbacks may want to call some OPP helper routines which may try to take the same opp_table->lock again and cause a deadlock. One such usecase was reported by Chanwoo Choi, where calling dev_pm_opp_disable() leads us to the devfreq's OPP notifier handler, which further calls dev_pm_opp_find_freq_floor() and it deadlocks. We don't really need the opp_table->lock to be held across the notifier call though, all we want to make sure is that the 'opp' doesn't get freed while being used from within the notifier chain. We can do it with help of dev_pm_opp_get/put() as well. Let's do it. Fixes: 5b650b388844 "PM / OPP: Take kref from _find_opp_table()" Reported-by: Chanwoo Choi Tested-by: Chanwoo Choi Reviewed-by: Stephen Boyd Reviewed-by: Chanwoo Choi Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

PM / OPP: Add dev_pm_opp_{set|put}_clkname()

2017-06-23T23:41:55Z

In order to support OPP switching, OPP layer needs to get pointer to the clock for the device. Simple cases work fine without using the routines added by this patch (i.e. by passing connection-id as NULL), but for a device with multiple clocks available, the OPP core needs to know the exact name of the clk to use. Add a new set of APIs to get that done. Tested-by: Rajendra Nayak Signed-off-by: Viresh Kumar Reviewed-by: Stephen Boyd Signed-off-by: Rafael J. Wysocki

PM / OPP: Don't create debugfs "supply-0" directory unnecessarily

2017-06-22T01:15:30Z

We create "supply-0" debugfs directory even if the device doesn't do voltage scaling. That looks confusing, as if the regulator is found but we never managed to get voltage levels for it. Avoid creating such a directory unnecessarily. Signed-off-by: Viresh Kumar Reviewed-by: Stephen Boyd Signed-off-by: Rafael J. Wysocki

PM / OPP: opp-microvolt is not optional if regulators are set

2017-06-22T01:15:30Z

If dev_pm_opp_set_regulators() is called for a device and its regulators are set in the OPP core, the OPP nodes for the device must contain the "opp-microvolt" property, otherwise there is something wrong and we better error out. Signed-off-by: Viresh Kumar Reviewed-by: Stephen Boyd Signed-off-by: Rafael J. Wysocki

PM / OPP: Don't create copy of regulators unnecessarily

2017-06-22T01:15:30Z

This code was required while the OPP core was managed with help of RCUs, but not anymore. Get rid of unnecessary alloc/memcpy operations. Signed-off-by: Viresh Kumar Reviewed-by: Stephen Boyd Signed-off-by: Rafael J. Wysocki

PM / OPP: Reorganize _generic_set_opp_regulator()

2017-06-22T01:15:29Z

The code was overly complicated here because of the limitations that we had with RCUs (Couldn't use opp-table and OPPs outside RCU protected section and can't call sleep-able routines from within that). But that is long gone now. Reorganize _generic_set_opp_regulator() in order to avoid using "struct dev_pm_set_opp_data" and copying data into it for the case where opp_table->set_opp is not set. Signed-off-by: Viresh Kumar Reviewed-by: Stephen Boyd Signed-off-by: Rafael J. Wysocki

PM / OPP: fix off-by-one bug in dev_pm_opp_get_max_volt_latency loop

2017-02-23T22:00:31Z

Reading array at given index before checking if index is valid results in illegal memory access. The bug was detected using KASAN framework. Signed-off-by: Andrzej Hajda Acked-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki

PM / OPP: Expose _of_get_opp_desc_node as dev_pm_opp API

2017-02-09T21:52:17Z

Rename _of_get_opp_desc_node to dev_pm_opp_of_get_opp_desc_node and add it to include/linux/pm_opp.h to allow other drivers, such as platform OPP and cpufreq drivers, to make use of it. Acked-by: Viresh Kumar Signed-off-by: Dave Gerlach Signed-off-by: Rafael J. Wysocki

PM / OPP: Make _find_opp_table_unlocked() static

2017-02-07T12:39:25Z

Fixes the following sparse warning: drivers/base/power/opp/core.c:49:18: warning: symbol '_find_opp_table_unlocked' was not declared. Should it be static? Signed-off-by: Wei Yongjun Reviewed-by: Stephen Boyd Acked-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki

PM / OPP: Simplify dev_pm_opp_get_max_volt_latency()

2017-01-30T08:22:22Z

dev_pm_opp_get_max_volt_latency() calls _find_opp_table() two times effectively. Merge _get_regulator_count() into dev_pm_opp_get_max_volt_latency() to avoid that. Signed-off-by: Viresh Kumar Reviewed-by: Stephen Boyd Signed-off-by: Rafael J. Wysocki