kernel/linux.git/drivers/hwmon/ftsteutates.c, branch v7.1

hwmon: (ftsteutates) Rely on subsystem locking

2025-10-17T12:59:13+00:00

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

hwmon: (ftsteutates) Fix TOCTOU race in fts_read()

2025-06-16T13:30:57+00:00

In the fts_read() function, when handling hwmon_pwm_auto_channels_temp, the code accesses the shared variable data->fan_source[channel] twice without holding any locks. It is first checked against FTS_FAN_SOURCE_INVALID, and if the check passes, it is read again when used as an argument to the BIT() macro. This creates a Time-of-Check to Time-of-Use (TOCTOU) race condition. Another thread executing fts_update_device() can modify the value of data->fan_source[channel] between the check and its use. If the value is changed to FTS_FAN_SOURCE_INVALID (0xff) during this window, the BIT() macro will be called with a large shift value (BIT(255)). A bit shift by a value greater than or equal to the type width is undefined behavior and can lead to a crash or incorrect values being returned to userspace. Fix this by reading data->fan_source[channel] into a local variable once, eliminating the race condition. Additionally, add a bounds check to ensure the value is less than BITS_PER_LONG before passing it to the BIT() macro, making the code more robust against undefined behavior. This possible bug was found by an experimental static analysis tool developed by our team. Fixes: 1c5759d8ce05 ("hwmon: (ftsteutates) Replace fanX_source with pwmX_auto_channels_temp") Cc: stable@vger.kernel.org Signed-off-by: Gui-Dong Han Link: https://lore.kernel.org/r/20250606071640.501262-1-hanguidong02@gmail.com Signed-off-by: Guenter Roeck

hwmon: Drop explicit initialization of struct i2c_device_id::driver_data to 0

2024-05-01T14:47:49+00:00

These drivers don't use the driver_data member of struct i2c_device_id, so don't explicitly initialize this member. This prepares putting driver_data in an anonymous union which requires either no initialization or named designators. But it's also a nice cleanup on its own. Signed-off-by: Uwe Kleine-König Link: https://lore.kernel.org/r/20240430085654.1028864-2-u.kleine-koenig@pengutronix.de Signed-off-by: Guenter Roeck

hwmon: Switch i2c drivers back to use .probe()

2023-06-08T13:41:17+00:00

After commit b8a1a4cd5a98 ("i2c: Provide a temporary .probe_new() call-back type"), all drivers being converted to .probe_new() and then 03c835f498b5 ("i2c: Switch .probe() to not take an id parameter") convert back to (the new) .probe() to be able to eventually drop .probe_new() from struct i2c_driver. Signed-off-by: Uwe Kleine-König Link: https://lore.kernel.org/r/20230505131718.1210071-1-u.kleine-koenig@pengutronix.de [groeck: Added missing change in pmbus/acbel-fsg032.c] Signed-off-by: Guenter Roeck

hwmon: ftsteutates: constify pointers to hwmon_channel_info

2023-04-19T14:08:35+00:00

Statically allocated array of pointed to hwmon_channel_info can be made const for safety. Signed-off-by: Krzysztof Kozlowski Signed-off-by: Guenter Roeck

hwmon: (ftsteutates) Add support for fanX_fault attributes

2023-02-03T15:30:10+00:00

The driver knows internally when a fan is not connected, but does not export this knowledge to userspace. Use the standard fanX_fault attributes to notify userspace if a fan is not connected. Tested on a Fujitsu DS3401-B1. Signed-off-by: Armin Wolf Link: https://lore.kernel.org/r/20230105225107.58308-4-W_Armin@gmx.de Signed-off-by: Guenter Roeck

hwmon: (ftsteutates) Replace fanX_source with pwmX_auto_channels_temp

2023-02-03T15:30:10+00:00

Replace the nonstandard fanX_source attributes with the standardized pwmX_auto_channels_temp attributes and document the special behaviour associated with those attributes. Tested on a Fujitsu DS3401-B1. Signed-off-by: Armin Wolf Link: https://lore.kernel.org/r/20230105225107.58308-3-W_Armin@gmx.de Signed-off-by: Guenter Roeck

hwmon: (ftsteutates) Convert to devm_hwmon_device_register_with_info()

2023-02-03T15:30:10+00:00

Convert driver to use devm_hwmon_device_register_with_info() to reduce module size by ~30%. Tested on a Fujitsu DS3401-B1. Signed-off-by: Armin Wolf Link: https://lore.kernel.org/r/20230105225107.58308-2-W_Armin@gmx.de Signed-off-by: Guenter Roeck

hwmon: (ftsteutates) Use devm_watchdog_register_device()

2023-02-03T15:30:09+00:00

Use devm_watchdog_register_device() to let devres take care of unregistering the watchdog at device removal. Remove the now pointless fts_remove() function. Tested on a Fujitsu DS3401-B1. Signed-off-by: Armin Wolf Link: https://lore.kernel.org/r/20221224041855.83981-4-W_Armin@gmx.de Signed-off-by: Guenter Roeck

hwmon: (ftsteutates) Fix scaling of measurements

2023-01-03T21:26:45+00:00

A user complained that the ftsteutates driver was displaying bogus values since its introduction. This happens because the sensor measurements need to be scaled in order to produce meaningful results: - the fan speed needs to be multiplied by 60 since its in RPS - the temperature is in degrees celsius and needs an offset of 64 - the voltage is in 1/256 of 3.3V The offical datasheet says the voltage needs to be divided by 256, but this is likely an off-by-one-error, since even the BIOS devides by 255 (otherwise 3.3V could not be measured). The voltage channels additionally need a board-specific multiplier, however this can be done by the driver since its board-specific. The reason the missing scaling of measurements is the way Fujitsu used this driver when it was still out-of-tree. Back then, all scaling was done in userspace by libsensors, even the generic one. Tested on a Fujitsu DS3401-B1. Fixes: 08426eda58e0 ("hwmon: Add driver for FTS BMC chip "Teutates"") Signed-off-by: Armin Wolf Link: https://lore.kernel.org/r/20221224041855.83981-2-W_Armin@gmx.de Signed-off-by: Guenter Roeck