linux.git/drivers/devfreq/governor_passive.c, branch v5.18 Clone of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git PM / devfreq: passive: Fix get_target_freq when not using required-opp 2021-06-24T01:37:35+00:00 Chanwoo Choi cw00.choi@samsung.com 2021-06-17T06:05:43+00:00 8c37d01e1a86073d15ea7084390fba58d9a1665f The 86ad9a24f21e ("PM / devfreq: Add required OPPs support to passive governor") supported the required-opp property for using devfreq passive governor. But, 86ad9a24f21e has caused the problem on use-case when required-opp is not used such as exynos-bus.c devfreq driver. So that fix the get_target_freq of passive governor for supporting the case of when required-opp is not used. Fixes: 86ad9a24f21e ("PM / devfreq: Add required OPPs support to passive governor") Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> 
The 86ad9a24f21e ("PM / devfreq: Add required OPPs support to passive governor")
supported the required-opp property for using devfreq passive governor.
But, 86ad9a24f21e has caused the problem on use-case when required-opp
is not used such as exynos-bus.c devfreq driver. So that fix the
get_target_freq of passive governor for supporting the case of when
required-opp is not used.

Fixes: 86ad9a24f21e ("PM / devfreq: Add required OPPs support to passive governor")
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
PM / devfreq: Add required OPPs support to passive governor 2021-02-04T11:18:16+00:00 Saravana Kannan saravanak@google.com 2021-02-04T08:14:24+00:00 86ad9a24f21ea7aac7deed06fe9556392568d88a Look at the required OPPs of the "parent" device to determine the OPP that is required from the slave device managed by the passive governor. This allows having mappings between a parent device and a slave device even when they don't have the same number of OPPs. While at it do a minor spell-fix and remove out label. Signed-off-by: Saravana Kannan <saravanak@google.com> Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com> Acked-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org> [ Viresh: Rearranged code and clean error paths ] Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> 
Look at the required OPPs of the "parent" device to determine the OPP that
is required from the slave device managed by the passive governor. This
allows having mappings between a parent device and a slave device even when
they don't have the same number of OPPs.

While at it do a minor spell-fix and remove out label.

Signed-off-by: Saravana Kannan <saravanak@google.com>
Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
[ Viresh: Rearranged code and clean error paths ]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
PM / devfreq: Add governor feature flag 2020-10-26T01:54:41+00:00 Chanwoo Choi cw00.choi@samsung.com 2020-10-05T05:48:01+00:00 0dd25a0d12a134cd2ba950d8c0530d4ece05c63b The devfreq governor is able to have the specific flag as follows in order to implement the specific feature. For example, devfreq allows user to change the governors on runtime via sysfs interface. But, if devfreq device uses 'passive' governor, don't allow user to change the governor. For this case, define the DEVFREQ_GOV_FLAG_IMMUTABLE and set it to flag of passive governor. [Definition for governor flag] - DEVFREQ_GOV_FLAG_IMMUTABLE : If immutable flag is set, governor is never changeable to other governors. - DEVFREQ_GOV_FLAG_IRQ_DRIVEN : Devfreq core won't schedule polling work for this governor if value is set. [Table of governor flag for devfreq governors] ------------------------------------------------------------------------------ | simple | perfor | power | user | passive | tegra30 | ondemand | mance | save | space| | ------------------------------------------------------------------------------ immutable | X | X | X | X | O | O interrupt_driven | X(polling)| X | X | X | X | O (irq) ------------------------------------------------------------------------------ Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Tested-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> 
The devfreq governor is able to have the specific flag as follows
in order to implement the specific feature. For example, devfreq allows
user to change the governors on runtime via sysfs interface.
But, if devfreq device uses 'passive' governor, don't allow user to change
the governor. For this case, define the DEVFREQ_GOV_FLAG_IMMUTABLE
and set it to flag of passive governor.

[Definition for governor flag]
- DEVFREQ_GOV_FLAG_IMMUTABLE
  : If immutable flag is set, governor is never changeable to other governors.
- DEVFREQ_GOV_FLAG_IRQ_DRIVEN
  : Devfreq core won't schedule polling work for this governor if value is set.

[Table of governor flag for devfreq governors]
------------------------------------------------------------------------------
                      | simple    | perfor | power | user | passive | tegra30
		      | ondemand  | mance  | save  | space|         |
------------------------------------------------------------------------------
immutable             | X         | X      | X     | X    | O       | O
interrupt_driven      | X(polling)| X      | X     | X    | X       | O (irq)
------------------------------------------------------------------------------

Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Tested-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
PM / devfreq: Unify frequency change to devfreq_update_target func 2020-10-26T01:52:37+00:00 Chanwoo Choi cw00.choi@samsung.com 2020-10-07T13:02:39+00:00 b4365423bb7adf9feb4659126eaec374dfbde806 The update_devfreq() and update_passive_devfreq() have the duplicate code when changing the target frequency on final stage. So, unify frequency change code to devfreq_update_target() to remove the duplicate code and to centralize the frequency change code. Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> 
The update_devfreq() and update_passive_devfreq() have the duplicate
code when changing the target frequency on final stage. So, unify
frequency change code to devfreq_update_target() to remove the
duplicate code and to centralize the frequency change code.

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
PM / devfreq: passive: fix compiler warning 2019-08-26T12:37:37+00:00 MyungJoo Ham myungjoo.ham@samsung.com 2019-08-26T12:37:37+00:00 0465814831a926ce2f83e8f606d067d86745234e The recent commit of PM / devfreq: passive: Use non-devm notifiers had incurred compiler warning, "unused variable 'dev'". Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> 
The recent commit of
PM / devfreq: passive: Use non-devm notifiers
had incurred compiler warning, "unused variable 'dev'".

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
PM / devfreq: passive: Use non-devm notifiers 2019-08-25T03:47:31+00:00 Leonard Crestez leonard.crestez@nxp.com 2019-08-08T16:54:08+00:00 0ef7c7cce43f6ecc2b96d447e69b2900a9655f7c The devfreq passive governor registers and unregisters devfreq transition notifiers on DEVFREQ_GOV_START/GOV_STOP using devm wrappers. If devfreq itself is registered with devm then a warning is triggered on rmmod from devm_devfreq_unregister_notifier. Call stack looks like this: devm_devfreq_unregister_notifier+0x30/0x40 devfreq_passive_event_handler+0x4c/0x88 devfreq_remove_device.part.8+0x6c/0x9c devm_devfreq_dev_release+0x18/0x20 release_nodes+0x1b0/0x220 devres_release_all+0x78/0x84 device_release_driver_internal+0x100/0x1c0 driver_detach+0x4c/0x90 bus_remove_driver+0x7c/0xd0 driver_unregister+0x2c/0x58 platform_driver_unregister+0x10/0x18 imx_devfreq_platdrv_exit+0x14/0xd40 [imx_devfreq] This happens because devres_release_all will first remove all the nodes into a separate todo list so the nested devres_release from devm_devfreq_unregister_notifier won't find anything. Fix the warning by calling the non-devm APIS for frequency notification. Using devm wrappers is not actually useful for a governor anyway: it relies on the devfreq core to correctly match the GOV_START/GOV_STOP notifications. Fixes: 996133119f57 ("PM / devfreq: Add new passive governor") Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com> Acked-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> 
The devfreq passive governor registers and unregisters devfreq
transition notifiers on DEVFREQ_GOV_START/GOV_STOP using devm wrappers.

If devfreq itself is registered with devm then a warning is triggered on
rmmod from devm_devfreq_unregister_notifier. Call stack looks like this:

	devm_devfreq_unregister_notifier+0x30/0x40
	devfreq_passive_event_handler+0x4c/0x88
	devfreq_remove_device.part.8+0x6c/0x9c
	devm_devfreq_dev_release+0x18/0x20
	release_nodes+0x1b0/0x220
	devres_release_all+0x78/0x84
	device_release_driver_internal+0x100/0x1c0
	driver_detach+0x4c/0x90
	bus_remove_driver+0x7c/0xd0
	driver_unregister+0x2c/0x58
	platform_driver_unregister+0x10/0x18
	imx_devfreq_platdrv_exit+0x14/0xd40 [imx_devfreq]

This happens because devres_release_all will first remove all the nodes
into a separate todo list so the nested devres_release from
devm_devfreq_unregister_notifier won't find anything.

Fix the warning by calling the non-devm APIS for frequency notification.
Using devm wrappers is not actually useful for a governor anyway: it
relies on the devfreq core to correctly match the GOV_START/GOV_STOP
notifications.

Fixes: 996133119f57 ("PM / devfreq: Add new passive governor")
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19T15:09:55+00:00 Thomas Gleixner tglx@linutronix.de 2019-06-04T08:11:33+00:00 d2912cb15bdda8ba4a5dd73396ad62641af2f520 Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Based on 2 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
PM / devfreq: Define the constant governor name 2017-10-26T08:08:40+00:00 Chanwoo Choi cw00.choi@samsung.com 2017-10-23T01:32:12+00:00 aa7c352f9841ab3fee5bf1de127a45e6310124a6 Prior to that, the devfreq device uses the governor name when adding the itself. In order to prevent the mistake used the wrong governor name, this patch defines the governor name as a constant and then uses them instead of using the string directly. Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> Cc: Kukjin Kim <kgene@kernel.org> Cc: Krzysztof Kozlowski <krzk@kernel.org> Cc: linux-samsung-soc@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org 
Prior to that, the devfreq device uses the governor name when adding
the itself. In order to prevent the mistake used the wrong governor name,
this patch defines the governor name as a constant and then uses them
instead of using the string directly.

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Cc: Kukjin Kim <kgene@kernel.org>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Cc: linux-samsung-soc@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Merge branch 'pm-devfreq' 2017-02-20T13:23:40+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2017-02-20T13:23:40+00:00 41ef3d1df037a429703db503e98fa948ee34b895 * pm-devfreq: PM / devfreq: Modify the device name as devfreq(X) for sysfs PM / devfreq: Simplify the sysfs name of devfreq-event device PM / devfreq: Remove unnecessary separate _remove_devfreq() PM / devfreq: Fix wrong trans_stat of passive devfreq device PM / devfreq: Fix available_governor sysfs PM / devfreq: exynos-ppmu: Show the registred device for ppmu device PM / devfreq: Fix the wrong description for userspace governor PM / devfreq: Fix the checkpatch warnings PM / devfreq: exynos-bus: Print the real clock rate of bus PM / devfreq: exynos-ppmu: Use the regmap interface to handle the registers PM / devfreq: exynos-bus: Add the detailed correlation for Exynos5433 PM / devfreq: Don't delete sysfs group twice 
* pm-devfreq:
  PM / devfreq: Modify the device name as devfreq(X) for sysfs
  PM / devfreq: Simplify the sysfs name of devfreq-event device
  PM / devfreq: Remove unnecessary separate _remove_devfreq()
  PM / devfreq: Fix wrong trans_stat of passive devfreq device
  PM / devfreq: Fix available_governor sysfs
  PM / devfreq: exynos-ppmu: Show the registred device for ppmu device
  PM / devfreq: Fix the wrong description for userspace governor
  PM / devfreq: Fix the checkpatch warnings
  PM / devfreq: exynos-bus: Print the real clock rate of bus
  PM / devfreq: exynos-ppmu: Use the regmap interface to handle the registers
  PM / devfreq: exynos-bus: Add the detailed correlation for Exynos5433
  PM / devfreq: Don't delete sysfs group twice
PM / devfreq: Fix wrong trans_stat of passive devfreq device 2017-01-31T06:47:32+00:00 Chanwoo Choi cw00.choi@samsung.com 2017-01-31T06:38:17+00:00 30582c25a4b4e0a5e456a309fde79b845e9473b2 Until now, the trans_stat information of passive devfreq is not updated. This patch updates the trans_stat information after setting the target frequency of passive devfreq device. Fixes: 996133119f57 ("PM / devfreq: Add new passive governor") Cc: stable@vger.kernel.org Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com> 
Until now, the trans_stat information of passive devfreq is not updated.
This patch updates the trans_stat information after setting the target
frequency of passive devfreq device.

Fixes: 996133119f57 ("PM / devfreq: Add new passive governor")
Cc: stable@vger.kernel.org
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>