From 1180c79fbf36e4c02e76ae4658509523437e52a4 Mon Sep 17 00:00:00 2001 From: Vadim Pasternak Date: Wed, 30 Jul 2025 23:17:15 +0300 Subject: [PATCH 1/4] hwmon: mlxreg-fan: Prevent fans from getting stuck at 0 RPM The fans controlled by the driver can get stuck at 0 RPM if they are configured below a 20% duty cycle. The driver tries to avoid this by enforcing a minimum duty cycle of 20%, but this is done after the fans are registered with the thermal subsystem. This is too late as the thermal subsystem can set their current state before the driver is able to enforce the minimum duty cycle. Fix by setting the minimum duty cycle before registering the fans with the thermal subsystem. Fixes: d7efb2ebc7b3 ("hwmon: (mlxreg-fan) Extend driver to support multiply cooling devices") Reported-by: Nikolay Aleksandrov Tested-by: Nikolay Aleksandrov Signed-off-by: Ido Schimmel Signed-off-by: Vadim Pasternak Link: https://lore.kernel.org/r/20250730201715.1111133-1-vadimp@nvidia.com Signed-off-by: Guenter Roeck --- drivers/hwmon/mlxreg-fan.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/hwmon/mlxreg-fan.c b/drivers/hwmon/mlxreg-fan.c index a5f89aab3fb4..c25a54d5b39a 100644 --- a/drivers/hwmon/mlxreg-fan.c +++ b/drivers/hwmon/mlxreg-fan.c @@ -561,15 +561,14 @@ static int mlxreg_fan_cooling_config(struct device *dev, struct mlxreg_fan *fan) if (!pwm->connected) continue; pwm->fan = fan; + /* Set minimal PWM speed. */ + pwm->last_hwmon_state = MLXREG_FAN_PWM_DUTY2STATE(MLXREG_FAN_MIN_DUTY); pwm->cdev = devm_thermal_of_cooling_device_register(dev, NULL, mlxreg_fan_name[i], pwm, &mlxreg_fan_cooling_ops); if (IS_ERR(pwm->cdev)) { dev_err(dev, "Failed to register cooling device\n"); return PTR_ERR(pwm->cdev); } - - /* Set minimal PWM speed. */ - pwm->last_hwmon_state = MLXREG_FAN_PWM_DUTY2STATE(MLXREG_FAN_MIN_DUTY); } return 0; From 98fd069dd87386d87eaf439e3c7b5767618926d2 Mon Sep 17 00:00:00 2001 From: Chris Packham Date: Fri, 29 Aug 2025 15:05:10 +1200 Subject: [PATCH 2/4] hwmon: (ina238) Correctly clamp temperature ina238_write_temp() was attempting to clamp the user input but was throwing away the result. Ensure that we clamp the value to the appropriate range before it is converted into a register value. Fixes: 0d9f596b1fe3 ("hwmon: (ina238) Modify the calculation formula to adapt to different chips") Signed-off-by: Chris Packham Link: https://lore.kernel.org/r/20250829030512.1179998-3-chris.packham@alliedtelesis.co.nz Signed-off-by: Guenter Roeck --- drivers/hwmon/ina238.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/hwmon/ina238.c b/drivers/hwmon/ina238.c index 5a394eeff676..4d3dc018ead9 100644 --- a/drivers/hwmon/ina238.c +++ b/drivers/hwmon/ina238.c @@ -572,7 +572,7 @@ static int ina238_write_temp(struct device *dev, u32 attr, long val) return -EOPNOTSUPP; /* Signed */ - regval = clamp_val(val, -40000, 125000); + val = clamp_val(val, -40000, 125000); regval = div_s64(val * 10000, data->config->temp_lsb) << data->config->temp_shift; regval = clamp_val(regval, S16_MIN, S16_MAX) & (0xffff << data->config->temp_shift); From bd7e7bc2cc2024035dfbc8239c9f4d8675793445 Mon Sep 17 00:00:00 2001 From: Guenter Roeck Date: Fri, 29 Aug 2025 06:49:51 -0700 Subject: [PATCH 3/4] hwmon: (ina238) Correctly clamp shunt voltage limit When clamping a register value, the result needs to be masked against the register size. This was missing, resulting in errors when trying to write negative limits. Fix by masking the clamping result against the register size. Fixes: eacb52f010a80 ("hwmon: Driver for Texas Instruments INA238") Cc: Nathan Rossi Cc: Chris Packham Signed-off-by: Guenter Roeck --- drivers/hwmon/ina238.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/hwmon/ina238.c b/drivers/hwmon/ina238.c index 4d3dc018ead9..c6b2734898d0 100644 --- a/drivers/hwmon/ina238.c +++ b/drivers/hwmon/ina238.c @@ -379,7 +379,7 @@ static int ina238_write_in(struct device *dev, u32 attr, int channel, regval = clamp_val(val, -163, 163); regval = (regval * 1000 * 4) / (INA238_SHUNT_VOLTAGE_LSB * data->gain); - regval = clamp_val(regval, S16_MIN, S16_MAX); + regval = clamp_val(regval, S16_MIN, S16_MAX) & 0xffff; switch (attr) { case hwmon_in_max: From c2623573178bab32990695fb729e9b69710ed66d Mon Sep 17 00:00:00 2001 From: Guenter Roeck Date: Fri, 29 Aug 2025 11:51:20 -0700 Subject: [PATCH 4/4] hwmon: (ina238) Correctly clamp power limits ina238_write_power() was attempting to clamp the user input but was throwing away the result. Ensure that we clamp the value to the appropriate range before it is converted into a register value. Fixes: 0d9f596b1fe34 ("hwmon: (ina238) Modify the calculation formula to adapt to different chips") Cc: Wenliang Yan Cc: Chris Packham Signed-off-by: Guenter Roeck --- drivers/hwmon/ina238.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/hwmon/ina238.c b/drivers/hwmon/ina238.c index c6b2734898d0..59a2c8889fa2 100644 --- a/drivers/hwmon/ina238.c +++ b/drivers/hwmon/ina238.c @@ -517,9 +517,10 @@ static int ina238_write_power(struct device *dev, u32 attr, long val) * Unsigned postive values. Compared against the 24-bit power register, * lower 8-bits are truncated. Same conversion to/from uW as POWER * register. + * The first clamp_val() is to establish a baseline to avoid overflows. */ - regval = clamp_val(val, 0, LONG_MAX); - regval = div_u64(val * 4 * 100 * data->rshunt, data->config->power_calculate_factor * + regval = clamp_val(val, 0, LONG_MAX / 2); + regval = div_u64(regval * 4 * 100 * data->rshunt, data->config->power_calculate_factor * 1000ULL * INA238_FIXED_SHUNT * data->gain); regval = clamp_val(regval >> 8, 0, U16_MAX);