kernel/linux.git/drivers/devfreq/devfreq.c, branch linux-6.0.y

PM/devfreq: governor: Add a private governor_data for governor

2023-01-07T10:15:46+00:00

commit 5fdded8448924e3631d466eea499b11606c43640 upstream. The member void *data in the structure devfreq can be overwrite by governor_userspace. For example: 1. The device driver assigned the devfreq governor to simple_ondemand by the function devfreq_add_device() and init the devfreq member void *data to a pointer of a static structure devfreq_simple_ondemand_data by the function devfreq_add_device(). 2. The user changed the devfreq governor to userspace by the command "echo userspace > /sys/class/devfreq/.../governor". 3. The governor userspace alloced a dynamic memory for the struct userspace_data and assigend the member void *data of devfreq to this memory by the function userspace_init(). 4. The user changed the devfreq governor back to simple_ondemand by the command "echo simple_ondemand > /sys/class/devfreq/.../governor". 5. The governor userspace exited and assigned the member void *data in the structure devfreq to NULL by the function userspace_exit(). 6. The governor simple_ondemand fetched the static information of devfreq_simple_ondemand_data in the function devfreq_simple_ondemand_func() but the member void *data of devfreq was assigned to NULL by the function userspace_exit(). 7. The information of upthreshold and downdifferential is lost and the governor simple_ondemand can't work correctly. The member void *data in the structure devfreq is designed for a static pointer used in a governor and inited by the function devfreq_add_device(). This patch add an element named governor_data in the devfreq structure which can be used by a governor(E.g userspace) who want to assign a private data to do some private things. Fixes: ce26c5bb9569 ("PM / devfreq: Add basic governors") Cc: stable@vger.kernel.org # 5.10+ Reviewed-by: Chanwoo Choi Acked-by: MyungJoo Ham Signed-off-by: Kant Fan Signed-off-by: Chanwoo Choi Signed-off-by: Greg Kroah-Hartman

PM / devfreq: shut up kernel-doc warnings

2022-07-15T02:40:08+00:00

There are 4 warnings there: drivers/devfreq/devfreq.c:707: warning: Function parameter or member 'val' not described in 'qos_min_notifier_call' drivers/devfreq/devfreq.c:707: warning: Function parameter or member 'ptr' not described in 'qos_min_notifier_call' drivers/devfreq/devfreq.c:717: warning: Function parameter or member 'val' not described in 'qos_max_notifier_call' drivers/devfreq/devfreq.c:717: warning: Function parameter or member 'ptr' not described in 'qos_max_notifier_call' It turns that neither val nor ptr are actually used on those function, so document as such. Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Chanwoo Choi

PM / devfreq: Rework freq_table to be local to devfreq struct

2022-06-29T20:11:17+00:00

On a devfreq PROBE_DEFER, the freq_table in the driver profile struct, is never reset and may be leaved in an undefined state. This comes from the fact that we store the freq_table in the driver profile struct that is commonly defined as static and not reset on PROBE_DEFER. We currently skip the reinit of the freq_table if we found it's already defined since a driver may declare his own freq_table. This logic is flawed in the case devfreq core generate a freq_table, set it in the profile struct and then PROBE_DEFER, freeing the freq_table. In this case devfreq will found a NOT NULL freq_table that has been freed, skip the freq_table generation and probe the driver based on the wrong table. To fix this and correctly handle PROBE_DEFER, use a local freq_table and max_state in the devfreq struct and never modify the freq_table present in the profile struct if it does provide it. Fixes: 0ec09ac2cebe ("PM / devfreq: Set the freq_table of devfreq device") Cc: stable@vger.kernel.org Signed-off-by: Christian Marangi Signed-off-by: Chanwoo Choi

PM / devfreq: Mute warning on governor PROBE_DEFER

2022-06-29T20:11:17+00:00

Don't print warning when a governor PROBE_DEFER as it's not a real GOV_START fail. Fixes: a03dacb0316f ("PM / devfreq: Add cpu based scaling support to passive governor") Signed-off-by: Christian 'Ansuel' Marangi Signed-off-by: Chanwoo Choi

PM / devfreq: Export devfreq_get_freq_range symbol within devfreq

2022-05-17T09:24:39+00:00

In order to get frequency range within devfreq governors, export devfreq_get_freq_range symbol within devfreq. Reviewed-by: Matthias Kaehlcke Tested-by: Chen-Yu Tsai Tested-by: Johnson Wang Signed-off-by: Chanwoo Choi

PM / devfreq: Reduce log severity for informative message

2021-12-16T02:29:54+00:00

Suppose devfreq_update_status() failure in devfreq_set_target() is not a critical error, reduces the log severity. Signed-off-by: Tzung-Bi Shih Signed-off-by: Chanwoo Choi

Merge branches 'pm-opp' and 'pm-cpufreq'

2021-11-10T13:06:51+00:00

Merge operating performance points (OPP) framework updates for and intel_pstate driver fixes for 5.16-rc1. * pm-opp: dt-bindings: opp: Allow multi-worded OPP entry name opp: Fix return in _opp_add_static_v2() PM / devfreq: tegra30: Check whether clk_round_rate() returns zero rate PM / devfreq: tegra30: Use resource-managed helpers PM / devfreq: Add devm_devfreq_add_governor() opp: Add more resource-managed variants of dev_pm_opp_of_add_table() opp: Change type of dev_pm_opp_attach_genpd(names) argument opp: Fix required-opps phandle array count check * pm-cpufreq: cpufreq: intel_pstate: Clear HWP Status during HWP Interrupt enable cpufreq: intel_pstate: Fix unchecked MSR 0x773 access cpufreq: intel_pstate: Clear HWP desired on suspend/shutdown and offline

PM / devfreq: Strengthen check for freq_table

2021-10-27T05:22:12+00:00

Since commit ea572f816032 ("PM / devfreq: Change return type of devfreq_set_freq_table()"), all devfreq devices are expected to have a valid freq_table. The devfreq core unconditionally dereferences freq_table in the sysfs code and in get_freq_range(). Therefore, we need to ensure that freq_table is both non-null and non-empty (length is > 0). If either check fails, replace the table using set_freq_table() or return the error. Signed-off-by: Samuel Holland Signed-off-by: Chanwoo Choi

PM / devfreq: Add devm_devfreq_add_governor()

2021-10-05T04:24:38+00:00

Add resource-managed variant of devfreq_add_governor(). Signed-off-by: Dmitry Osipenko Acked-by: Chanwoo Choi Signed-off-by: Viresh Kumar

devfreq: use HZ macros

2021-09-08T18:50:26+00:00

HZ unit conversion macros are available in units.h, use them and remove the duplicate definition. The new macro has an unsigned long type. All the code is dealing with unsigned long and the code using the macro is doing a coercitive cast to unsigned long. Link: https://lkml.kernel.org/r/20210816114732.1834145-5-daniel.lezcano@linaro.org Signed-off-by: Daniel Lezcano Reviewed-by: Christian Eggers Reviewed-by: Andy Shevchenko Acked-by: Chanwoo Choi Cc: Guenter Roeck Cc: Jonathan Cameron Cc: Jonathan Cameron Cc: Kyungmin Park Cc: Lars-Peter Clausen Cc: Lukasz Luba Cc: Maxime Coquelin Cc: Miquel Raynal Cc: MyungJoo Ham Cc: Peter Meerwald Cc: "Rafael J. Wysocki" Cc: Zhang Rui Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds