Pali Rohár wrote on 27.05.2016 12:45: > […] > Looks like there are two different problems with dell-smm-hwmon driver: > 1) Fan speed going randomly up and down without system freeze > […] > So for problem 1) I need to know: > > * Is it regression? […]
Yes, it is known to be a regression from f989e55452, as identified by Jan in https://bugzilla.kernel.org/show_bug.cgi?id=100121#c13 I just verified and reverted that change on top of 4.6; the problem with the fan speed indeed goes away. So I tried a few things and came to the conclusion: the problem shows up as soon as i8k_get_fan_type() (introduced in f989e55452) is called somewhere. Find below the minimal patch I could come up to that makes the fan act normal on the Studio 8000 I have here (it's just meant as a reference and not meant to be applied, as it leaves unused functions around). CU, knurd --- dell-smm-hwmon.c-unmodified 2016-05-27 13:05:58.441654144 +0200 +++ dell-smm-hwmon.c 2016-05-27 14:49:31.896224380 +0200 @@ -686,14 +686,10 @@ static SENSOR_DEVICE_ATTR(temp4_label, S_IRUGO, i8k_hwmon_show_temp_label, NULL, 3); static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, i8k_hwmon_show_fan, NULL, 0); -static SENSOR_DEVICE_ATTR(fan1_label, S_IRUGO, i8k_hwmon_show_fan_label, NULL, - 0); static SENSOR_DEVICE_ATTR(pwm1, S_IRUGO | S_IWUSR, i8k_hwmon_show_pwm, i8k_hwmon_set_pwm, 0); static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, i8k_hwmon_show_fan, NULL, 1); -static SENSOR_DEVICE_ATTR(fan2_label, S_IRUGO, i8k_hwmon_show_fan_label, NULL, - 1); static SENSOR_DEVICE_ATTR(pwm2, S_IRUGO | S_IWUSR, i8k_hwmon_show_pwm, i8k_hwmon_set_pwm, 1); @@ -707,11 +703,9 @@ &sensor_dev_attr_temp4_input.dev_attr.attr, /* 6 */ &sensor_dev_attr_temp4_label.dev_attr.attr, /* 7 */ &sensor_dev_attr_fan1_input.dev_attr.attr, /* 8 */ - &sensor_dev_attr_fan1_label.dev_attr.attr, /* 9 */ - &sensor_dev_attr_pwm1.dev_attr.attr, /* 10 */ - &sensor_dev_attr_fan2_input.dev_attr.attr, /* 11 */ - &sensor_dev_attr_fan2_label.dev_attr.attr, /* 12 */ - &sensor_dev_attr_pwm2.dev_attr.attr, /* 13 */ + &sensor_dev_attr_pwm1.dev_attr.attr, /* 9 */ + &sensor_dev_attr_fan2_input.dev_attr.attr, /* 10 */ + &sensor_dev_attr_pwm2.dev_attr.attr, /* 11 */ NULL }; @@ -730,10 +724,10 @@ if (index >= 6 && index <= 7 && !(i8k_hwmon_flags & I8K_HWMON_HAVE_TEMP4)) return 0; - if (index >= 8 && index <= 10 && + if (index >= 8 && index <= 9 && !(i8k_hwmon_flags & I8K_HWMON_HAVE_FAN1)) return 0; - if (index >= 11 && index <= 13 && + if (index >= 10 && index <= 11 && !(i8k_hwmon_flags & I8K_HWMON_HAVE_FAN2)) return 0; @@ -768,12 +762,14 @@ i8k_hwmon_flags |= I8K_HWMON_HAVE_TEMP4; /* First fan attributes, if fan type is OK */ - err = i8k_get_fan_type(0); + // err = i8k_get_fan_type(0); + err = i8k_get_fan_status(0); if (err >= 0) i8k_hwmon_flags |= I8K_HWMON_HAVE_FAN1; /* Second fan attributes, if fan type is OK */ - err = i8k_get_fan_type(1); + // err = i8k_get_fan_type(1); + err = i8k_get_fan_status(1); if (err >= 0) i8k_hwmon_flags |= I8K_HWMON_HAVE_FAN2; @@ -932,17 +928,6 @@ static struct dmi_system_id i8k_blacklist_dmi_table[] __initdata = { { /* - * CPU fan speed going up and down on Dell Studio XPS 8000 - * for unknown reasons. - */ - .ident = "Dell Studio XPS 8000", - .matches = { - DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Dell Inc."), - DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Studio XPS 8000"), - }, - }, - { - /* * CPU fan speed going up and down on Dell Studio XPS 8100 * for unknown reasons. */
