On more Dell machines (e.g. Dell Precision M3800) fan_type() call is too
expensive (CPU is too long in SMM mode) and cause kernel to hang. This is
bug in Dell SMM or BIOS.
This patch caches type for each fan (as it should not change) and changes
the way how fan presense is detected. First it try function fan_status()
as was before commit f989e55452 ("i8k: Add support for fan labels"). And
if that fails fallback to fan_type(). *_status() functions can fail in case
fan is not currently accessible (e.g. present on GPU which is currently
turned off).
Reported-by: Tolga Cakir <cevelnet@gmail.com>
Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=112021
Cc: stable@vger.kernel.org # v4.0+, will need backport
Tested-by: Tolga Cakir <cevelnet@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Some Dell machines have especially broken SMM or BIOS which cause that once
fan_type() is called then CPU fan speed going randomly up and down. And for
fixing this behaviour reboot is required.
So this patch creates fan_type blacklist of affected Dell machines and
disallow fan_type() call on them to prevent that erratic behaviour.
Old blacklist which disabled loading driver on some machines added in
commits a4b45b25f1 ("hwmon: (dell-smm) Blacklist Dell Studio XPS 8100")
and 6220f4ebd7 ("hwmon: (dell-smm) Blacklist Dell Studio XPS 8000") were
moved to FAN_TYPE blacklist.
Reported-by: Jan C Peters <jcpeters89@gmail.com>
Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=100121
Cc: stable@vger.kernel.org # v4.0+, will need backport
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
For security reasons ordinary user must not be able to control fan speed
via /proc/i8k by default. Some malicious software running under "nobody"
user could be able to turn fan off and cause HW problems. So this patch
changes default value of "restricted" parameter to 1.
Also restrict reading of DMI_PRODUCT_SERIAL from /proc/i8k via "restricted"
parameter. It is because non root user cannot read DMI_PRODUCT_SERIAL from
sysfs file /sys/class/dmi/id/product_serial.
Old non secure behaviour of file /proc/i8k can be achieved by loading this
module with "restricted" parameter set to 0.
Note that this patch has effects only for kernels compiled with CONFIG_I8K
and only for file /proc/i8k. Hwmon interface provided by this driver was
not changed and root access for setting fan speed was needed also before.
Reported-by: Mario Limonciello <Mario_Limonciello@dell.com>
Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Cc: stable@vger.kernel.org # will need backport
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
ABI of I8K_BIOS_VERSION ioctl can return only number. But new BIOS versions
contain also other characters, which does not fit into that ABI. So in case
of non digit values return -EINVAL.
Reported-by: Mario Limonciello <Mario_Limonciello@dell.com>
Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The code handles this variable always as unsigned, so adapt the type.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
We need to read a bunch of registers on each compute unit and possibly
on the current CPU too. Disable preemption around it. Otherwise, you
get:
BUG: using smp_processor_id() in preemptible [00000000] code: systemd-udevd/327
caller is read_registers+0x6a/0x110 [fam15h_power]
CPU: 3 PID: 327 Comm: systemd-udevd Not tainted 4.7.0-rc1+ #4
Hardware name: HP HP EliteBook 745 G3/807E, BIOS N73 Ver. 01.08 01/28/2016
...
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Rui Huang <ray.huang@amd.com>
Cc: Sherry Hurwitz <sherry.hurwitz@amd.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Acked-by: Huang Rui <ray.huang@amd.com>
Tested-by: Huang Rui <ray.huang@amd.com>
Fixes: fa79434499 ("hwmon: (fam15h_power) Add compute unit accumulated power")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Pull hwmon fixlets from Jean Delvare.
* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
Documentation/hwmon: Update links in max34440
hwmon: (emc2103) Fix typo in MODULE_PARM_DESC
Pull thermal management updates from Zhang Rui:
- Introduce generic ADC thermal driver, based on OF thermal (Laxman
Dewangan)
- Introduce new thermal driver for Tango chips (Marc Gonzalez)
- Rockchip driver support for RK3399, RK3366, and some fixes (Caesar
Wang, Elaine Zhang and Shawn Lin)
- Add CPU power cooling model to Mediatek thermal driver (Dawei Chien)
- Wider usage of dev_thermal_zone_of_sensor_register (Eduardo Valentin)
- TI thermal driver gained a new maintainer (Keerthy).
- Enabled powerclamp driver by checking CPU feature and package cstate
counter instead of CPU whitelist (Jacob Pan)
- Various fixes on thermal governor, OF thermal, Tegra, and RCAR
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux: (50 commits)
thermal: tango: initialize TEMPSI_CFG
thermal: rockchip: use the usleep_range instead of udelay
thermal: rockchip: add the notes for better reading
thermal: rockchip: Support RK3366 SoCs in the thermal driver
thermal: rockchip: handle the power sequence for tsadc controller
thermal: rockchip: update the tsadc table for rk3399
thermal: rockchip: fixes the code_to_temp for tsadc driver
thermal: rockchip: disable thermal->clk in err case
thermal: tegra: add Tegra132 specific SOC_THERM driver
thermal: fix ptr_ret.cocci warnings
thermal: mediatek: Add cpu dynamic power cooling model.
thermal: generic-adc: Add ADC based thermal sensor driver
thermal: generic-adc: Add DT binding for ADC based thermal sensor
thermal: tegra: fix static checker warning
thermal: tegra: mark PM functions __maybe_unused
thermal: add temperature sensor support for tango SoC
thermal: hisilicon: fix IRQ imbalance enabling
thermal: hisilicon: support to use any sensor
thermal: rcar: Remove binding docs for r8a7794
thermal: tegra: add PM support
...
This set of changes introduces an atomic API to the PWM subsystem. This
is influenced by the DRM atomic API that was introduced a while back,
though it is obviously a lot simpler. The fundamental idea remains the
same, though: drivers provide a single callback to implement the atomic
configuration of a PWM channel.
As a side-effect the PWM subsystem gains the ability for initial state
retrieval, so that the logical state mirrors that of the hardware. Many
use-cases don't care about this, but for others it is essential.
These new features require changes in all users, which these patches
take care of. The core is transitioned to use the atomic callback if
available and provides a fallback mechanism for other drivers.
Changes to transition users and drivers to the atomic API are postponed
to v4.8.
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Merge tag 'pwm/for-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm
Pull pwm updates from Thierry Reding:
"This set of changes introduces an atomic API to the PWM subsystem.
This is influenced by the DRM atomic API that was introduced a while
back, though it is obviously a lot simpler. The fundamental idea
remains the same, though: drivers provide a single callback to
implement the atomic configuration of a PWM channel.
As a side-effect the PWM subsystem gains the ability for initial state
retrieval, so that the logical state mirrors that of the hardware.
Many use-cases don't care about this, but for others it is essential.
These new features require changes in all users, which these patches
take care of. The core is transitioned to use the atomic callback if
available and provides a fallback mechanism for other drivers.
Changes to transition users and drivers to the atomic API are
postponed to v4.8"
* tag 'pwm/for-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm: (30 commits)
pwm: Add information about polarity, duty cycle and period to debugfs
pwm: Switch to the atomic API
pwm: Update documentation
pwm: Add core infrastructure to allow atomic updates
pwm: Add hardware readout infrastructure
pwm: Move the enabled/disabled info into pwm_state
pwm: Introduce the pwm_state concept
pwm: Keep PWM state in sync with hardware state
ARM: Explicitly apply PWM config extracted from pwm_args
drm: i915: Explicitly apply PWM config extracted from pwm_args
input: misc: pwm-beeper: Explicitly apply PWM config extracted from pwm_args
input: misc: max8997: Explicitly apply PWM config extracted from pwm_args
backlight: lm3630a: explicitly apply PWM config extracted from pwm_args
backlight: lp855x: Explicitly apply PWM config extracted from pwm_args
backlight: lp8788: Explicitly apply PWM config extracted from pwm_args
backlight: pwm_bl: Use pwm_get_args() where appropriate
fbdev: ssd1307fb: Use pwm_get_args() where appropriate
regulator: pwm: Use pwm_get_args() where appropriate
leds: pwm: Use pwm_get_args() where appropriate
input: misc: max77693: Use pwm_get_args() where appropriate
...
This changes the driver to use the devm_ version
of thermal_zone_of_sensor_register and cleans
up the local points and unregister calls.
Cc: Jean Delvare <jdelvare@suse.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: lm-sensors@lm-sensors.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
This changes the driver to use the devm_ version
of thermal_zone_of_sensor_register and cleans
up the local points and unregister calls.
Cc: Jean Delvare <jdelvare@suse.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: lm-sensors@lm-sensors.org
Cc: linux-kernel@vger.kernel.org
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
This changes the driver to use the devm_ version
of thermal_zone_of_sensor_register and cleans
up the local points and unregister calls.
Cc: Jean Delvare <jdelvare@suse.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: lm-sensors@lm-sensors.org
Cc: linux-kernel@vger.kernel.org
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
This changes the driver to use the devm_ version
of thermal_zone_of_sensor_register and cleans
up the local points and unregister calls.
Cc: Jean Delvare <jdelvare@suse.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: lm-sensors@lm-sensors.org
Cc: linux-kernel@vger.kernel.org
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
The PWM framework has clarified the concept of reference PWM config (the
platform dependent config retrieved from the DT or the PWM lookup table)
and real PWM state.
Use pwm_get_args() when the PWM user wants to retrieve this reference
config and not the current state.
This is part of the rework allowing the PWM framework to support
hardware readout and expose real PWM state even when the PWM has just
been requested (before the user calls pwm_config/enable/disable()).
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Kamil Debski <k.debski@samsung.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
IT8628E is functionally identical to IT8620E.
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Several of the chips supported by this driver have a configuration
register to enable fan4 and fan5. Use those registers to determine
if fan4 and fan5 tachometers are supported.
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
On/Off mode is only supported for pwm controls 0-2, and not supported at all for
IT8603E/IT8623E. For pwm controls 3-6 and for IT8603E/IT8623E, SmartGuardian mode
is always enabled. Use it and set the pwm value to the maximum if fan control
is disabled.
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Fix various checkpatch complaints to clean up the code and
make it easier to read.
CHECK: Do not include the paragraph about writing to the FSF
CHECK: Alignment should match open parenthesis
CHECK: Logical continuations should be on the previous line
CHECK: No space is necessary after a cast
CHECK: Please don't use multiple blank lines
CHECK: Please use a blank line after function/struct/union/enum
declarations
CHECK: spaces preferred around that '+' (ctx:VxV)
WARNING: Missing a blank line after declarations
No functional change.
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Using array size defines makes it much easier to find errors
in index values and loop counts.
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Using the BIT macro makes the code a little easier to read and has the
added benefit of making checkpatch happy.
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
IT8620E supports three additional voltage sensors.
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Voltage registers are non-sequential. Use a register array instead
of a macro to map sensor index to register to simplify the code
and to make it easier to add additional voltage sensors.
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Add support for the additional temperature sensors on IT8620E.
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Convert to use devm_hwmon_device_register_with_groups to simplify
code and reduce code size. This also attaches sysfs attributes
to the hwmon device and no longer to the platform device.
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Use is_visible to determine if attributes should be generated or not.
This simplifies the code and reduces object size by about 120 bytes
on x86_64.
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Simplify code and reduce object size by about 250 bytes on x86_64.
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Simplify code and reduce object size by almost 500 bytes on x86_64.
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Simplify code and reduce object size by more than 200 bytes on x86_64.
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Simplify code and reduce object size by more than 300 bytes on x86_64.
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The Super-IO chip can also reside at SIO address 0x4e, and there can be
two Super-IO chips in the system. Add support for it.
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This will let us support more than one chip on different SIO addresses
with the same driver.
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Using the same varible name for function names and as static
variable invites misuse and prevents us from adding support
for a second chip. Rename pdev to it87_pdev and limit its use
to where it is needed.
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Return directly on errors if there is no cleanup necessary.
Don't create an error message on memory allocation errors.
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Recent chips have a separate register to select the pwm2 frequency.
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
IT8620E supports up to 6 pwm channels. Add support for it.
Also check if fan tachometers 4..6 are enabled before instantiating
the respective sysfs attributes.
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
AVCC3 is supported on IT8620E, similar to IT8603E. Add feature flag
to indicate AVCC3 support. Don't enable it for now on IT8620E since
it is unclear if this chip supports it correctly.
Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This patch adds a platform check function to make code more readable.
Signed-off-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This patch adds the description to explain the TDP reporting mechanism
and accumulated power algorithm.
Signed-off-by: Huang Rui <ray.huang@amd.com>
Cc: Borislav Petkov <bp@alien8.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This patch introduces an algorithm that computes the average power by
reading a delta value of “core power accumulator” register during
measurement interval, and then dividing delta value by the length of
the time interval.
User is able to use power1_average entry to measure the processor power
consumption and power1_average_interval entry to set the interval.
A simple example:
ray@hr-ub:~/tip$ sensors
fam15h_power-pci-00c4
Adapter: PCI adapter
power1: 19.58 mW (avg = 2.55 mW, interval = 0.01 s)
(crit = 15.00 W)
...
The result is current average processor power consumption in 10
millisecond. The unit of the result is uWatt.
Suggested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Huang Rui <ray.huang@amd.com>
Cc: Borislav Petkov <bp@alien8.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
PTSC is the performance timestamp counter value in a cpu core and the
cores in one compute unit have the fixed frequency. So it picks up the
performance timestamp counter value of the first core per compute unit
to measure the interval for average power per compute unit.
Signed-off-by: Huang Rui <ray.huang@amd.com>
Cc: Borislav Petkov <bp@alien8.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This patch adds a member in fam15h_power_data which specifies the
compute unit accumulated power. It adds do_read_registers_on_cu to do
all the read to all MSRs and run it on one of the online cores on each
compute unit with smp_call_function_many(). This behavior can decrease
IPI numbers.
Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This patch adds CONFIG_CPU_SUP_AMD as the dependence of fam15h_power
driver. Because the following patch will use the interface from
x86/kernel/cpu/amd.c.
Otherwise, the below error might be encountered:
All errors (new ones prefixed by >>):
drivers/built-in.o: In function `fam15h_power_probe':
>> fam15h_power.c:(.text+0x26e3a3): undefined reference to
>> `amd_get_cores_per_cu'
fam15h_power.c:(.text+0x26e41e): undefined reference to
`amd_get_cores_per_cu'
Reported-by: build test robot <lkp@intel.com>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Add basic support for the Maxim Integrated MAX31722/MAX31723 SPI
temperature sensors / thermostats.
Includes:
- ACPI support;
- raw temperature readings;
- power management
Datasheet:
https://datasheets.maximintegrated.com/en/ds/MAX31722-MAX31723.pdf
Signed-off-by: Tiberiu Breana <tiberiu.a.breana@intel.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
On ads7828 the internal reference defaults to off upon power up. When
using internal reference, it needs to be turned on and the voltage needs
to settle before normal conversion cycle can be started. Hence perform a
dummy read in the probe to enable the internal reference allowing the
voltage to settle before performing a normal read.
Without this fix, the first read from the ADC when using internal
reference always returns incorrect data.
Signed-off-by: Akshay Bhat <akshay.bhat@timesys.com>
Cc: stable@vger.kernel.org # v4.1+
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
arm:pxa_defconfig can result in the following crash if the max1111 driver
is not instantiated.
Unhandled fault: page domain fault (0x01b) at 0x00000000
pgd = c0004000
[00000000] *pgd=00000000
Internal error: : 1b [#1] PREEMPT ARM
Modules linked in:
CPU: 0 PID: 300 Comm: kworker/0:1 Not tainted 4.5.0-01301-g1701f680407c #10
Hardware name: SHARP Akita
Workqueue: events sharpsl_charge_toggle
task: c390a000 ti: c391e000 task.ti: c391e000
PC is at max1111_read_channel+0x20/0x30
LR is at sharpsl_pm_pxa_read_max1111+0x2c/0x3c
pc : [<c03aaab0>] lr : [<c0024b50>] psr: 20000013
...
[<c03aaab0>] (max1111_read_channel) from [<c0024b50>]
(sharpsl_pm_pxa_read_max1111+0x2c/0x3c)
[<c0024b50>] (sharpsl_pm_pxa_read_max1111) from [<c00262e0>]
(spitzpm_read_devdata+0x5c/0xc4)
[<c00262e0>] (spitzpm_read_devdata) from [<c0024094>]
(sharpsl_check_battery_temp+0x78/0x110)
[<c0024094>] (sharpsl_check_battery_temp) from [<c0024f9c>]
(sharpsl_charge_toggle+0x48/0x110)
[<c0024f9c>] (sharpsl_charge_toggle) from [<c004429c>]
(process_one_work+0x14c/0x48c)
[<c004429c>] (process_one_work) from [<c0044618>] (worker_thread+0x3c/0x5d4)
[<c0044618>] (worker_thread) from [<c004a238>] (kthread+0xd0/0xec)
[<c004a238>] (kthread) from [<c000a670>] (ret_from_fork+0x14/0x24)
This can occur because the SPI controller driver (SPI_PXA2XX) is built as
module and thus not necessarily loaded. While building SPI_PXA2XX into the
kernel would make the problem disappear, it appears prudent to ensure that
the driver is instantiated before accessing its data structures.
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: stable@vger.kernel.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
