In lm78_isa_found() there is REALLY_SLOW_IO defined around some port
accesses, probably in order to wait between multiple accesses.
Unfortunately this isn't making any difference compared to not having
this define since more than a decade, as REALLY_SLOW_IO needs to be
defined while "#include <asm/io.h>" is called to have an effect.
As there seem not to be any outstanding issues in spite of this having
no effect, just drop the "#define" and add a remark to the related
comment.
Signed-off-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20251126162018.5676-3-jgross@suse.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
In sy7636a_sensor_probe(), regulator_enable() is called but if
devm_hwmon_device_register_with_info() fails, the function returns
without calling regulator_disable(), leaving the regulator enabled
and leaking the reference count.
Switch to devm_regulator_get_enable() to automatically
manage the regulator resource.
Fixes: de34a40532 ("hwmon: sy7636a: Add temperature driver for sy7636a")
Suggested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Haotian Zhang <vulab@iscas.ac.cn>
Link: https://lore.kernel.org/r/20251126162602.2086-1-vulab@iscas.ac.cn
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The macro FAN_FROM_REG evaluates its arguments multiple times. When used
with shared driver data, this leads to Time-of-Check to Time-of-Use
(TOCTOU) race conditions, potentially causing divide-by-zero errors.
Convert the macro to a static function to ensure arguments are evaluated
only once.
Additionally, in fan_div_store, move the reading of the old register
value and the calculation of the minimum limit inside the update lock.
This ensures that the read-modify-write sequence operates on consistent
data, preventing race conditions during fan divider updates.
Link: https://lore.kernel.org/all/CALbr=LYJ_ehtp53HXEVkSpYoub+XYSTU8Rg=o1xxMJ8=5z8B-g@mail.gmail.com/
Signed-off-by: Gui-Dong Han <hanguidong02@gmail.com>
Link: https://lore.kernel.org/r/20251124165900.4713-1-hanguidong02@gmail.com
[groeck: Dropped unnecessary line split]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The macros IN_FROM_REG, TEMP_FROM_REG, and RPM_FROM_REG evaluate their
arguments multiple times. These macros are used in lockless show functions
involving shared driver data, leading to Time-of-Check to Time-of-Use race
conditions.
For example, RPM_FROM_REG checks if a value is 0 or 255, and then uses it
in a division. If the value is modified by another thread to 0 after the
check but before the division, it causes a divide-by-zero error.
Convert these macros to static functions. This guarantees that arguments
are evaluated only once (pass-by-value), fixing the race conditions.
Adhere to the principle of minimal changes by only converting the specific
macros involved in these lockless contexts.
Link: https://lore.kernel.org/all/CALbr=LYJ_ehtp53HXEVkSpYoub+XYSTU8Rg=o1xxMJ8=5z8B-g@mail.gmail.com/
Signed-off-by: Gui-Dong Han <hanguidong02@gmail.com>
Link: https://lore.kernel.org/r/20251120041331.1917570-1-hanguidong02@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The System Management Controller on Apple Silicon devices is responsible
for integrating and exposing the data reported by the vast array of
hardware monitoring sensors present on these devices. It is also
responsible for fan control, and allows users to manually set fan
speeds if they so desire. Add a hwmon driver to expose current,
power, temperature, and voltage monitoring sensors, as well as
fan speed monitoring and control via the SMC on Apple Silicon devices.
The SMC firmware has no consistency between devices, even when they
share an SoC. The FourCC keys used to access sensors are almost
random. An M1 Mac mini will have different FourCCs for its CPU core
temperature sensors to an M1 MacBook Pro, for example. For this
reason, the valid sensors for a given device are specified in a
child of the SMC Devicetree node. The driver uses this information
to determine which sensors to make available at runtime.
Reviewed-by: Neal Gompa <neal@gompa.dev>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Co-developed-by: Janne Grunau <j@jannau.net>
Signed-off-by: Janne Grunau <j@jannau.net>
Signed-off-by: James Calligeros <jcalligeros99@gmail.com>
Link: https://lore.kernel.org/r/20251112-macsmc-subdevs-v5-6-728e4b91fe81@gmail.com
[groeck: Added Documentation to index]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The RAA229141A is a digital dual output multiphase (X+Y ≤ 12) PWM
controller designed to be compliant with Intel VR13, VR13.HC, VR14 and
VR14.Cloud specifications, targeting VCORE and auxiliary rails.
The RAA229141A supports the Intel SVID interface along with PMBus V1.3
specifications, making it ideal for controlling the microprocessor core and
system rails in Intel VR13, VR13.HC, VR14 and VR14.Cloud platforms.
Signed-off-by: Jeff Lin <jefflin994697@gmail.com>
Link: https://lore.kernel.org/r/20251106104519.2014853-1-jefflin994697@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Add a driver for the ST Microelectronics TSC1641 16-bit high-precision
power monitor. The driver supports reading bus voltage, current, power,
and temperature. Sysfs attributes are exposed for shunt resistor and
update interval. The driver integrates with the hwmon subsystem and
supports optional ALERT pin polarity configuration.
Signed-off-by: Igor Reznichenko <igor@reznichenko.net>
Link: https://lore.kernel.org/r/20251105201406.1210856-3-igor@reznichenko.net
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Add support for dht20 temperature and humidity sensor from Aosong.
Modify aht10 driver to handle different init command for dht20 sensor by
adding init_cmd entry in the driver data. dht20 sensor is compatible with
aht10 hwmon driver with this change.
Tested on TI am62x SK board with dht20 sensor connected at i2c-2 port.
Signed-off-by: Akhilesh Patil <akhilesh@ee.iitb.ac.in>
Link: https://lore.kernel.org/r/2025112-94320-906858@bhairav-test.ee.iitb.ac.in
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Attribute access is now serialized in the hardware monitoring core,
so locking in the driver code is no longer necessary. Drop it.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Attribute access is now serialized in the hardware monitoring core,
so locking in the driver code is no longer necessary. Drop it.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The driver does not perform any locking, does not execute or use any sleep
related functionality, and does not allocate memory. Drop the unnecessary
include files.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Attribute access is now serialized in the hardware monitoring core,
so locking in the driver code is no longer necessary. Drop it.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The driver does not perform any locking, does not execute or use any sleep
related functionality, and does not allocate memory. Drop the unnecessary
include files.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Attribute access is now serialized in the hardware monitoring core,
so locking in the driver code is no longer necessary. Drop it.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Attribute access is now serialized in the hardware monitoring core,
so locking in the driver code is no longer necessary. Drop it.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Attribute access is now serialized in the hardware monitoring core,
so locking in the driver code is no longer necessary. Drop it.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Attribute access is now serialized in the hardware monitoring core,
so locking in the driver code is no longer necessary. Drop it.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Attribute access is now serialized in the hardware monitoring core,
so locking in the driver code is no longer necessary. Drop it.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Attribute access is now serialized in the hardware monitoring core,
so locking in the driver code is no longer necessary. Drop it.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Attribute access is now serialized in the hardware monitoring core,
so locking in the driver code is no longer necessary. Drop it.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Attribute access is now serialized in the hardware monitoring core,
so locking in the driver code is no longer necessary. Drop it.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Attribute access is now serialized in the hardware monitoring core,
so locking in the driver code is no longer necessary. Drop it.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Attribute access is now serialized in the hardware monitoring core,
so locking in the driver code is no longer necessary. Drop it.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Attribute access is now serialized in the hardware monitoring core,
so locking in the driver code is no longer necessary. Drop it.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Attribute access is now serialized in the hardware monitoring core,
so locking in the driver code is no longer necessary. Drop it.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Attribute access is now serialized in the hardware monitoring core,
so locking in the driver code is no longer necessary. Drop it.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Attribute access is now serialized in the hardware monitoring core,
so locking in the driver code is no longer necessary. Drop it.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
