diff options
Diffstat (limited to 'Documentation/hwmon')
| -rw-r--r-- | Documentation/hwmon/acpi_power_meter | 51 | ||||
| -rw-r--r-- | Documentation/hwmon/hpfall.c | 115 | ||||
| -rw-r--r-- | Documentation/hwmon/pc87427 | 2 |
3 files changed, 132 insertions, 36 deletions
diff --git a/Documentation/hwmon/acpi_power_meter b/Documentation/hwmon/acpi_power_meter new file mode 100644 index 0000000..c80399a --- /dev/null +++ b/Documentation/hwmon/acpi_power_meter @@ -0,0 +1,51 @@ +Kernel driver power_meter +========================= + +This driver talks to ACPI 4.0 power meters. + +Supported systems: + * Any recent system with ACPI 4.0. + Prefix: 'power_meter' + Datasheet: http://acpi.info/, section 10.4. + +Author: Darrick J. Wong + +Description +----------- + +This driver implements sensor reading support for the power meters exposed in +the ACPI 4.0 spec (Chapter 10.4). These devices have a simple set of +features--a power meter that returns average power use over a configurable +interval, an optional capping mechanism, and a couple of trip points. The +sysfs interface conforms with the specification outlined in the "Power" section +of Documentation/hwmon/sysfs-interface. + +Special Features +---------------- + +The power[1-*]_is_battery knob indicates if the power supply is a battery. +Both power[1-*]_average_{min,max} must be set before the trip points will work. +When both of them are set, an ACPI event will be broadcast on the ACPI netlink +socket and a poll notification will be sent to the appropriate +power[1-*]_average sysfs file. + +The power[1-*]_{model_number, serial_number, oem_info} fields display arbitrary +strings that ACPI provides with the meter. The measures/ directory contains +symlinks to the devices that this meter measures. + +Some computers have the ability to enforce a power cap in hardware. If this is +the case, the power[1-*]_cap and related sysfs files will appear. When the +average power consumption exceeds the cap, an ACPI event will be broadcast on +the netlink event socket and a poll notification will be sent to the +appropriate power[1-*]_alarm file to indicate that capping has begun, and the +hardware has taken action to reduce power consumption. Most likely this will +result in reduced performance. + +There are a few other ACPI notifications that can be sent by the firmware. In +all cases the ACPI event will be broadcast on the ACPI netlink event socket as +well as sent as a poll notification to a sysfs file. The events are as +follows: + +power[1-*]_cap will be notified if the firmware changes the power cap. +power[1-*]_interval will be notified if the firmware changes the averaging +interval. diff --git a/Documentation/hwmon/hpfall.c b/Documentation/hwmon/hpfall.c index bbea1cc..681ec22 100644 --- a/Documentation/hwmon/hpfall.c +++ b/Documentation/hwmon/hpfall.c @@ -16,6 +16,34 @@ #include <stdint.h> #include <errno.h> #include <signal.h> +#include <sys/mman.h> +#include <sched.h> + +char unload_heads_path[64]; + +int set_unload_heads_path(char *device) +{ + char devname[64]; + + if (strlen(device) <= 5 || strncmp(device, "/dev/", 5) != 0) + return -EINVAL; + strncpy(devname, device + 5, sizeof(devname)); + + snprintf(unload_heads_path, sizeof(unload_heads_path), + "/sys/block/%s/device/unload_heads", devname); + return 0; +} +int valid_disk(void) +{ + int fd = open(unload_heads_path, O_RDONLY); + if (fd < 0) { + perror(unload_heads_path); + return 0; + } + + close(fd); + return 1; +} void write_int(char *path, int i) { @@ -40,7 +68,7 @@ void set_led(int on) void protect(int seconds) { - write_int("/sys/block/sda/device/unload_heads", seconds*1000); + write_int(unload_heads_path, seconds*1000); } int on_ac(void) @@ -57,45 +85,62 @@ void ignore_me(void) { protect(0); set_led(0); - } -int main(int argc, char* argv[]) +int main(int argc, char **argv) { - int fd, ret; + int fd, ret; + struct sched_param param; + + if (argc == 1) + ret = set_unload_heads_path("/dev/sda"); + else if (argc == 2) + ret = set_unload_heads_path(argv[1]); + else + ret = -EINVAL; + + if (ret || !valid_disk()) { + fprintf(stderr, "usage: %s <device> (default: /dev/sda)\n", + argv[0]); + exit(1); + } + + fd = open("/dev/freefall", O_RDONLY); + if (fd < 0) { + perror("/dev/freefall"); + return EXIT_FAILURE; + } - fd = open("/dev/freefall", O_RDONLY); - if (fd < 0) { - perror("open"); - return EXIT_FAILURE; - } + daemon(0, 0); + param.sched_priority = sched_get_priority_max(SCHED_FIFO); + sched_setscheduler(0, SCHED_FIFO, ¶m); + mlockall(MCL_CURRENT|MCL_FUTURE); signal(SIGALRM, ignore_me); - for (;;) { - unsigned char count; - - ret = read(fd, &count, sizeof(count)); - alarm(0); - if ((ret == -1) && (errno == EINTR)) { - /* Alarm expired, time to unpark the heads */ - continue; - } - - if (ret != sizeof(count)) { - perror("read"); - break; - } - - protect(21); - set_led(1); - if (1 || on_ac() || lid_open()) { - alarm(2); - } else { - alarm(20); - } - } - - close(fd); - return EXIT_SUCCESS; + for (;;) { + unsigned char count; + + ret = read(fd, &count, sizeof(count)); + alarm(0); + if ((ret == -1) && (errno == EINTR)) { + /* Alarm expired, time to unpark the heads */ + continue; + } + + if (ret != sizeof(count)) { + perror("read"); + break; + } + + protect(21); + set_led(1); + if (1 || on_ac() || lid_open()) + alarm(2); + else + alarm(20); + } + + close(fd); + return EXIT_SUCCESS; } diff --git a/Documentation/hwmon/pc87427 b/Documentation/hwmon/pc87427 index d1ebbe5..db5cc12 100644 --- a/Documentation/hwmon/pc87427 +++ b/Documentation/hwmon/pc87427 @@ -34,5 +34,5 @@ Fan rotation speeds are reported as 14-bit values from a gated clock signal. Speeds down to 83 RPM can be measured. An alarm is triggered if the rotation speed drops below a programmable -limit. Another alarm is triggered if the speed is too low to to be measured +limit. Another alarm is triggered if the speed is too low to be measured (including stalled or missing fan). |