linux/drivers/cpufreq
Viresh Kumar 32e1ac30b6 cpufreq: Register drivers only after CPU devices have been registered
[ Upstream commit 46770be0cf ]

The cpufreq core heavily depends on the availability of the struct
device for CPUs and if they aren't available at the time cpufreq driver
is registered, we will never succeed in making cpufreq work.

This happens due to following sequence of events:

- cpufreq_register_driver()
  - subsys_interface_register()
  - return 0; //successful registration of driver

... at a later point of time

- register_cpu();
  - device_register();
    - bus_probe_device();
      - sif->add_dev();
	- cpufreq_add_dev();
	  - get_cpu_device(); //FAILS
  - per_cpu(cpu_sys_devices, num) = &cpu->dev; //used by get_cpu_device()
  - return 0; //CPU registered successfully

Because the per-cpu variable cpu_sys_devices is set only after the CPU
device is regsitered, cpufreq will never be able to get it when
cpufreq_add_dev() is called.

This patch avoids this failure by making sure device structure of at
least CPU0 is available when the cpufreq driver is registered, else
return -EPROBE_DEFER.

Reported-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Co-developed-by: Amit Kucheria <amit.kucheria@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Amit Kucheria <amit.kucheria@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-12-31 16:45:26 +01:00
..
acpi-cpufreq.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
amd_freq_sensitivity.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
arm_big_little.c cpufreq: arm_big_little: Register an Energy Model 2019-02-07 09:55:11 +05:30
arm_big_little.h cpufreq: arm_big_little: make function arguments and structure pointer const 2017-11-08 23:22:19 +01:00
armada-8k-cpufreq.c cpufreq: ap806: Add NULL check after kcalloc 2019-07-22 11:12:15 +05:30
armada-37xx-cpufreq.c cpufreq: armada-37xx: Remove set but not used variable 'freq' 2019-06-03 11:26:38 +05:30
bmips-cpufreq.c cpufreq: Make cpufreq_generic_init() return void 2019-07-16 10:20:11 +02:00
brcmstb-avs-cpufreq.c cpufreq: brcmstb-avs-cpufreq: Fix types for voltage/frequency 2019-06-04 09:31:41 +05:30
cppc_cpufreq.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441 2019-06-05 17:37:17 +02:00
cpufreq_conservative.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
cpufreq_governor_attr_set.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
cpufreq_governor.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
cpufreq_governor.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
cpufreq_ondemand.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
cpufreq_ondemand.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
cpufreq_performance.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
cpufreq_powersave.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
cpufreq_stats.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
cpufreq_userspace.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
cpufreq-dt-platdev.c Merge branch 'cpufreq/qcom-updates' into cpufreq/arm/linux-next 2019-09-03 07:55:22 +05:30
cpufreq-dt.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
cpufreq-dt.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
cpufreq-nforce2.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 166 2019-05-30 11:26:39 -07:00
cpufreq.c cpufreq: Register drivers only after CPU devices have been registered 2019-12-31 16:45:26 +01:00
davinci-cpufreq.c Merge branch 'pm-cpufreq' 2019-07-18 09:49:30 +02:00
e_powersaver.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 166 2019-05-30 11:26:39 -07:00
elanfreq.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
freq_table.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
gx-suspmod.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
highbank-cpufreq.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
ia64-acpi-cpufreq.c treewide: Add SPDX license identifier for more missed files 2019-05-21 10:50:45 +02:00
imx6q-cpufreq.c Merge branch 'pm-cpufreq' 2019-07-18 09:49:30 +02:00
imx-cpufreq-dt.c cpufreq: imx-cpufreq-dt: Correct i.MX8MN's default speed grade value 2019-12-13 08:43:28 +01:00
intel_pstate.c cpufreq: intel_pstate: Fix invalid EPB setting 2019-11-08 11:29:58 +01:00
Kconfig treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
Kconfig.arm Merge branch 'cpufreq/qcom-updates' into cpufreq/arm/linux-next 2019-09-03 07:55:22 +05:30
Kconfig.powerpc treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
Kconfig.x86 treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
kirkwood-cpufreq.c cpufreq: Make cpufreq_generic_init() return void 2019-07-16 10:20:11 +02:00
longhaul.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 166 2019-05-30 11:26:39 -07:00
longhaul.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 166 2019-05-30 11:26:39 -07:00
longrun.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 166 2019-05-30 11:26:39 -07:00
loongson1-cpufreq.c cpufreq: Make cpufreq_generic_init() return void 2019-07-16 10:20:11 +02:00
loongson2_cpufreq.c cpufreq: Make cpufreq_generic_init() return void 2019-07-16 10:20:11 +02:00
Makefile Merge branch 'cpufreq/qcom-updates' into cpufreq/arm/linux-next 2019-09-03 07:55:22 +05:30
maple-cpufreq.c Merge branch 'pm-cpufreq' 2019-07-18 09:49:30 +02:00
mediatek-cpufreq.c cpufreq: mediatek: Add support for mt8183 2019-08-22 11:31:04 +05:30
mvebu-cpufreq.c cpufreq: mvebu: Remove OPPs using dev_pm_opp_remove() 2018-09-19 14:56:44 -07:00
omap-cpufreq.c Merge branch 'pm-cpufreq' 2019-07-18 09:49:30 +02:00
p4-clockmod.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
pasemi-cpufreq.c cpufreq/pasemi: fix use-after-free in pas_cpufreq_cpu_init() 2019-07-23 09:49:10 +02:00
pcc-cpufreq.c cpufreq: pcc-cpufreq: Fail initialization if driver cannot be registered 2019-06-17 12:25:30 +02:00
pmac32-cpufreq.c Merge branch 'pm-cpufreq' 2019-07-18 09:49:30 +02:00
pmac64-cpufreq.c Merge branch 'pm-cpufreq' 2019-07-18 09:49:30 +02:00
powernow-k6.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 166 2019-05-30 11:26:39 -07:00
powernow-k7.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 166 2019-05-30 11:26:39 -07:00
powernow-k7.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 166 2019-05-30 11:26:39 -07:00
powernow-k8.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 166 2019-05-30 11:26:39 -07:00
powernow-k8.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 347 2019-06-05 17:37:08 +02:00
powernv-cpufreq.c cpufreq: powernv: fix stack bloat and hard limit on number of CPUs 2019-12-17 19:56:26 +01:00
ppc_cbe_cpufreq_pervasive.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 153 2019-05-30 11:26:32 -07:00
ppc_cbe_cpufreq_pmi.c cpufreq: Use per-policy frequency QoS 2019-10-21 02:05:21 +02:00
ppc_cbe_cpufreq.c cpufreq: powerpc_cbe: Switch to QoS requests for freq limits 2019-08-26 10:02:01 +02:00
ppc_cbe_cpufreq.h cpufreq: powerpc_cbe: Switch to QoS requests for freq limits 2019-08-26 10:02:01 +02:00
pxa2xx-cpufreq.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
pxa3xx-cpufreq.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
qcom-cpufreq-hw.c cpufreq: qcom-hw: invoke frequency-invariance setter function 2019-08-22 11:31:04 +05:30
qcom-cpufreq-nvmem.c cpufreq: qcom: Add support for qcs404 on nvmem driver 2019-09-03 07:55:00 +05:30
qoriq-cpufreq.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
raspberrypi-cpufreq.c cpufreq: add driver for Raspberry Pi 2019-06-13 08:58:22 +05:30
s3c24xx-cpufreq-debugfs.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
s3c24xx-cpufreq.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
s3c64xx-cpufreq.c Merge branch 'pm-cpufreq' 2019-07-18 09:49:30 +02:00
s3c2410-cpufreq.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
s3c2412-cpufreq.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
s3c2416-cpufreq.c Merge branch 'pm-cpufreq' 2019-07-18 09:49:30 +02:00
s3c2440-cpufreq.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
s5pv210-cpufreq.c Merge branch 'pm-cpufreq' 2019-07-18 09:49:30 +02:00
sa1100-cpufreq.c cpufreq: Make cpufreq_generic_init() return void 2019-07-16 10:20:11 +02:00
sa1110-cpufreq.c Merge branch 'pm-cpufreq' 2019-07-18 09:49:30 +02:00
sc520_freq.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
scmi-cpufreq.c Merge branch 'pm-opp' 2019-03-04 11:19:14 +01:00
scpi-cpufreq.c cpufreq: scpi: Fix use after free 2019-03-28 11:14:31 +01:00
sfi-cpufreq.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 235 2019-06-19 17:09:07 +02:00
sh-cpufreq.c cpufreq: sh: Don't validate the frequency table twice 2018-03-20 12:07:52 +01:00
sparc-us2e-cpufreq.c treewide: Add SPDX license identifier for more missed files 2019-05-21 10:50:45 +02:00
sparc-us3-cpufreq.c treewide: Add SPDX license identifier for more missed files 2019-05-21 10:50:45 +02:00
spear-cpufreq.c cpufreq: Make cpufreq_generic_init() return void 2019-07-16 10:20:11 +02:00
speedstep-centrino.c treewide: Add SPDX license identifier for more missed files 2019-05-21 10:50:45 +02:00
speedstep-ich.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 166 2019-05-30 11:26:39 -07:00
speedstep-lib.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 166 2019-05-30 11:26:39 -07:00
speedstep-lib.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 166 2019-05-30 11:26:39 -07:00
speedstep-smi.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 166 2019-05-30 11:26:39 -07:00
sti-cpufreq.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 312 2019-06-05 17:37:04 +02:00
sun50i-cpufreq-nvmem.c cpufreq: sun50i: Fix CPU speed bin detection 2019-12-31 16:44:38 +01:00
tango-cpufreq.c cpufreq: dt: Don't use generic platdev driver for tango 2017-07-22 02:20:59 +02:00
tegra20-cpufreq.c cpufreq: Make cpufreq_generic_init() return void 2019-07-16 10:20:11 +02:00
tegra124-cpufreq.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282 2019-06-05 17:36:37 +02:00
tegra186-cpufreq.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 288 2019-06-05 17:36:37 +02:00
ti-cpufreq.c cpufreq: ti-cpufreq: Mark expected switch fall-through 2019-07-30 08:10:45 +05:30
unicore2-cpufreq.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
vexpress-spc-cpufreq.c cpufreq: arm_big_little: make cpufreq_arm_bL_ops structures const 2017-11-08 23:22:20 +01:00