From 7fb2616e249184e217f9818a7662596165710ea4 Mon Sep 17 00:00:00 2001 From: Frans Pop Date: Mon, 26 Oct 2009 08:39:01 +0100 Subject: [PATCH 1/4] acpi: thermal: display forced passive trip points in proc Users can force a passive trip point for a thermal zone that does not have _PSV defined in ACPI by setting the passive attribute in sysfs. It's useful to display such trip points in /proc/acpi/thermal_zone. .../TZ1/cooling_mode: .../TZ1/polling_frequency:polling frequency: 10 seconds .../TZ1/state:state: ok .../TZ1/temperature:temperature: 53 C .../TZ1/trip_points:critical (S5): 110 C .../TZ1/trip_points:passive (forced): 95 C And if not set (passive is 0): .../TZ1/trip_points:passive (forced): Signed-off-by: Frans Pop Acked-by: Zhang Rui Signed-off-by: Andrew Morton Signed-off-by: Len Brown --- drivers/acpi/thermal.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/acpi/thermal.c b/drivers/acpi/thermal.c index 65f67815902..9073ada8883 100644 --- a/drivers/acpi/thermal.c +++ b/drivers/acpi/thermal.c @@ -1052,6 +1052,13 @@ static int acpi_thermal_trip_seq_show(struct seq_file *seq, void *offset) acpi_device_bid(device)); } seq_puts(seq, "\n"); + } else { + seq_printf(seq, "passive (forced):"); + if (tz->thermal_zone->forced_passive) + seq_printf(seq, " %i C\n", + tz->thermal_zone->forced_passive / 1000); + else + seq_printf(seq, "\n"); } for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) { From 3d8e3ad879441ae14c5957b933028daf39d252b0 Mon Sep 17 00:00:00 2001 From: Frans Pop Date: Mon, 26 Oct 2009 08:39:02 +0100 Subject: [PATCH 2/4] thermal: add sanity check for the passive attribute Values below 1000 milli-celsius don't make sense and can cause the system to go into a thermal heart attack: the actual temperature will always be lower and thus the system will be throttled down to its lowest setting. An additional problem is that values below 1000 will show as 0 in /proc/acpi/thermal/TZx/trip_points:passive. cat passive 0 echo -n 90 >passive bash: echo: write error: Invalid argument echo -n 90000 >passive cat passive 90000 Signed-off-by: Frans Pop Acked-by: Zhang Rui Signed-off-by: Andrew Morton Signed-off-by: Len Brown --- Documentation/thermal/sysfs-api.txt | 1 + drivers/thermal/thermal_sys.c | 6 ++++++ 2 files changed, 7 insertions(+) diff --git a/Documentation/thermal/sysfs-api.txt b/Documentation/thermal/sysfs-api.txt index a87dc277a5c..cb3d15bc1ae 100644 --- a/Documentation/thermal/sysfs-api.txt +++ b/Documentation/thermal/sysfs-api.txt @@ -206,6 +206,7 @@ passive passive trip point for the zone. Activation is done by polling with an interval of 1 second. Unit: millidegrees Celsius + Valid values: 0 (disabled) or greater than 1000 RW, Optional ***************************** diff --git a/drivers/thermal/thermal_sys.c b/drivers/thermal/thermal_sys.c index 6f8d8f97121..310e40ab00b 100644 --- a/drivers/thermal/thermal_sys.c +++ b/drivers/thermal/thermal_sys.c @@ -225,6 +225,12 @@ passive_store(struct device *dev, struct device_attribute *attr, if (!sscanf(buf, "%d\n", &state)) return -EINVAL; + /* sanity check: values below 1000 millicelcius don't make sense + * and can cause the system to go into a thermal heart attack + */ + if (state && state < 1000) + return -EINVAL; + if (state && !tz->forced_passive) { mutex_lock(&thermal_list_lock); list_for_each_entry(cdev, &thermal_cdev_list, node) { From e4143b0324a6a468cb00c4341cd20d60cc441252 Mon Sep 17 00:00:00 2001 From: Frans Pop Date: Mon, 26 Oct 2009 08:39:03 +0100 Subject: [PATCH 3/4] thermal: Only set passive_delay for forced_passive cooling Setting polling_delay is useless as passive_delay has priority, so the value shown in proc isn't the actual polling delay. It also gives the impression to the user that he can change the polling interval through proc, while in fact he can't. Also, unset passive_delay when the forced passive trip point is unbound to allow polling to be disabled. Signed-off-by: Frans Pop Acked-by: Matthew Garrett Acked-by: Zhang Rui Signed-off-by: Andrew Morton Signed-off-by: Len Brown --- drivers/thermal/thermal_sys.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) diff --git a/drivers/thermal/thermal_sys.c b/drivers/thermal/thermal_sys.c index 310e40ab00b..663c2fdba77 100644 --- a/drivers/thermal/thermal_sys.c +++ b/drivers/thermal/thermal_sys.c @@ -241,6 +241,8 @@ passive_store(struct device *dev, struct device_attribute *attr, cdev); } mutex_unlock(&thermal_list_lock); + if (!tz->passive_delay) + tz->passive_delay = 1000; } else if (!state && tz->forced_passive) { mutex_lock(&thermal_list_lock); list_for_each_entry(cdev, &thermal_cdev_list, node) { @@ -251,17 +253,12 @@ passive_store(struct device *dev, struct device_attribute *attr, cdev); } mutex_unlock(&thermal_list_lock); + tz->passive_delay = 0; } tz->tc1 = 1; tz->tc2 = 1; - if (!tz->passive_delay) - tz->passive_delay = 1000; - - if (!tz->polling_delay) - tz->polling_delay = 10000; - tz->forced_passive = state; thermal_zone_device_update(tz); From 3767cb54ac718eb049d2a29f7a575ab923550ba5 Mon Sep 17 00:00:00 2001 From: Frans Pop Date: Mon, 26 Oct 2009 08:39:04 +0100 Subject: [PATCH 4/4] thermal: disable polling if passive_delay and polling_delay are both unset Otherwise polling will continue for the thermal zone even when it is no longer needed, for example because forced passive cooling was disabled. Signed-off-by: Frans Pop Acked-by: Matthew Garrett Acked-by: Zhang Rui Signed-off-by: Andrew Morton Signed-off-by: Len Brown --- drivers/thermal/thermal_sys.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/thermal/thermal_sys.c b/drivers/thermal/thermal_sys.c index 663c2fdba77..3bc72ea57e0 100644 --- a/drivers/thermal/thermal_sys.c +++ b/drivers/thermal/thermal_sys.c @@ -1019,6 +1019,8 @@ void thermal_zone_device_update(struct thermal_zone_device *tz) thermal_zone_device_set_polling(tz, tz->passive_delay); else if (tz->polling_delay) thermal_zone_device_set_polling(tz, tz->polling_delay); + else + thermal_zone_device_set_polling(tz, 0); mutex_unlock(&tz->lock); } EXPORT_SYMBOL(thermal_zone_device_update);