kernel/linux.git/drivers/devfreq/devfreq.c, branch v3.16.76

PM / devfreq: Fix devfreq_add_device() when drivers are built as modules.

2019-02-11T17:53:24+00:00

commit 23c7b54ca1cd1797ef39169ab85e6d46f1c2d061 upstream. When the devfreq driver and the governor driver are built as modules, the call to devfreq_add_device() or governor_store() fails because the governor driver is not loaded at the time the devfreq driver loads. The devfreq driver has a build dependency on the governor but also should have a runtime dependency. We need to make sure that the governor driver is loaded before the devfreq driver. This patch fixes this bug by adding a try_then_request_governor() function. First tries to find the governor, and then, if it is not found, it requests the module and tries again. Fixes: 1b5c1be2c88e (PM / devfreq: map devfreq drivers to governor using name) Signed-off-by: Enric Balletbo i Serra Reviewed-by: Chanwoo Choi Signed-off-by: MyungJoo Ham [bwh: Backported to 3.16: - Use string literal instead of DEVFREQ_GOV_SIMPLE_ONDEMAND - Adjust context] Signed-off-by: Ben Hutchings

PM / devfreq: Propagate error from devfreq_add_device()

2018-06-16T21:21:45+00:00

commit d1bf2d30728f310f72296b54f0651ecdb09cbb12 upstream. Propagate the error of devfreq_add_device() in devm_devfreq_add_device() rather than statically returning ENOMEM. This makes it slightly faster to pinpoint the cause of a returned error. Fixes: 8cd84092d35e ("PM / devfreq: Add resource-managed function for devfreq device") Acked-by: Chanwoo Choi Signed-off-by: Bjorn Andersson Signed-off-by: MyungJoo Ham Signed-off-by: Ben Hutchings

PM / devfreq: Fix the bug of devfreq_add_device when governor is NULL

2017-03-16T02:26:43+00:00

commit 73613b16cb5c5d5a659fc8832eff99eead3f9afb upstream. This patch fixes the bug of devfreq_add_device(). The devfreq device must have the default governor. If find_devfreq_governor() returns error, devfreq_add_device() fail to add the devfreq instance. Fixes: 1b5c1be2c88e (PM / devfreq: map devfreq drivers to governor using name) Signed-off-by: Chanwoo Choi Signed-off-by: Rafael J. Wysocki Signed-off-by: Ben Hutchings

PM / devfreq: Add proper locking around list_del()

2017-03-16T02:26:43+00:00

commit 0f376c9cd86c23f37312d37748b233660ef9d9af upstream. Use devfreq_list_lock around list_del() to prevent list corruption. Signed-off-by: Axel Lin Acked-by: MyungJoo Ham Signed-off-by: Rafael J. Wysocki Signed-off-by: Ben Hutchings

PM / devfreq: Fix incorrect type issue.

2016-11-20T01:17:39+00:00

commit 5f25f066f75a67835abb5e400471a27abd09395b upstream. time_in_state in struct devfreq is defined as unsigned long, so devm_kzalloc should use sizeof(unsigned long) as argument instead of sizeof(unsigned int), otherwise it will cause unexpected result in 64bit system. Signed-off-by: Xiaolong Ye Signed-off-by: Kevin Liu Signed-off-by: MyungJoo Ham Signed-off-by: Ben Hutchings

PM / devfreq: Add devm_devfreq_{register,unregister}_opp_notfier function

2014-05-24T13:33:41+00:00

This patch add resource-managed function for devfreq opp as following functions. The devm_devfreq_register_opp_notifier() manages automatically the registration of devfreq opp using device resource management. - devm_devfreq_register_opp_notifier - devm_devfreq_unregister_opp_notifier() Signed-off-by: Chanwoo Choi Signed-off-by: MyungJoo Ham

PM / devfreq: Add resource-managed function for devfreq device

2014-05-24T13:33:38+00:00

This patch add resource-managed function for devfreq device as following functions. The devm_devfreq_add_device() manages automatically the memory of devfreq device using device resource management. - devm_devfreq_add_device() - devm_devfreq_remove_device() Signed-off-by: Chanwoo Choi Signed-off-by: MyungJoo Ham

PM / devfreq: Fix devfreq_remove_device() to improve the sequence of resource free

2014-05-24T13:33:34+00:00

This patch modify devfreq_remove_device() to improve the sequence of resource free. If executing existing devfreq_remove_device(), this function always executes _remove_devfreq() twice. In result, second _remove_devfreq() always return error value. So, This patch resolves complicated function sequence as following: [Flow sequence before modification] devfreq_remove_device() _remove_devfreq(devfreq, false) kfree(devfreq); /* Free devfreq */ if (!skip ...) { /* skip is false */ device_unregister(&devfreq->dev) put_device(&devfreq->dev); ... dev->release() devfreq_dev_release() _remove_devfreq(devfreq, true) <- Recall to free devfreq /* * Always return error without freeing resource because * already _remove_devfreq() frees the memory of devfreq. */ } [Flow sequence after modification] devfreq_remove_device device_unregister(&devfreq->dev) put_device(&devfreq->dev); .. dev->release() devfreq_dev_release() _remove_devfreq() kfree(devfreq); /* Free devfreq */ Signed-off-by: Chanwoo Choi [Merge conflict resolved by MyungJoo] Signed-off-by: MyungJoo Ham

PM / devfreq: Rewrite devfreq_update_status() to fix multiple bugs

2014-03-21T02:16:30+00:00

The current devfreq_update_status() has the following bugs: - If previous frequency doesn't have a valid level, it does an out of bounds access into the trans_table and causes memory corruption. - When the new frequency doesn't have a valid level, the time spent in the new frequency is counted towards the next valid frequency switch instead of being ignored. - The time spent on the previous frequency is added to the new frequency's stats instead of the previous frequency's stats. This patch fixes all of this. Signed-off-by: Saravana Kannan Signed-off-by: MyungJoo Ham

Merge branch 'pm-devfreq'

2013-11-07T18:24:20+00:00

* pm-devfreq: PM / devfreq: create_freezable_workqueue() doesn't return an ERR_PTR PM / devfreq: Remove duplicate header file inclusion in exynos5_bus.c PM / devfreq: Use devm_* APIs in exynos5_bus.c PM / devfreq: Remove redundant platform_set_drvdata() in exynos5_bus.c PM / devfreq: Fix incorrect usage of IS_ERR_OR_NULL in exynos5_bus.c