[net-next-2.6.git] / Documentation / hwmon / hpfall.c

/* Disk protection for HP machines.
 *
 * Copyright 2008 Eric Piel
 * Copyright 2009 Pavel Machek <pavel@ucw.cz>
 *
 * GPLv2.
 */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <string.h>
#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)
{
	char buf[1024];
	int fd = open(path, O_RDWR);
	if (fd < 0) {
		perror("open");
		exit(1);
	}
	sprintf(buf, "%d", i);
	if (write(fd, buf, strlen(buf)) != strlen(buf)) {
		perror("write");
		exit(1);
	}
	close(fd);
}

void set_led(int on)
{
	write_int("/sys/class/leds/hp::hddprotect/brightness", on);
}

void protect(int seconds)
{
	write_int(unload_heads_path, seconds*1000);
}

int on_ac(void)
{
//	/sys/class/power_supply/AC0/online
}

int lid_open(void)
{
//	/proc/acpi/button/lid/LID/state
}

void ignore_me(void)
{
	protect(0);
	set_led(0);
}

int main(int argc, char **argv)
{
	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;
	}

	daemon(0, 0);
	param.sched_priority = sched_get_priority_max(SCHED_FIFO);
	sched_setscheduler(0, SCHED_FIFO, &param);
	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;
}
Commit	Line	Data
ef2cfc79 PM	1	/* Disk protection for HP machines.
	2	*
	3	* Copyright 2008 Eric Piel
a2531293	4	* Copyright 2009 Pavel Machek <pavel@ucw.cz>
ef2cfc79 PM	5	*
	6	* GPLv2.
	7	*/
	8
	9	#include <stdio.h>
	10	#include <stdlib.h>
	11	#include <unistd.h>
	12	#include <fcntl.h>
	13	#include <sys/stat.h>
	14	#include <sys/types.h>
	15	#include <string.h>
	16	#include <stdint.h>
	17	#include <errno.h>
	18	#include <signal.h>
2bace8b9 CT	19	#include <sys/mman.h>
2bace8b9 CT	20	#include <sched.h>
ef2cfc79	21
be3990b7 FP	22	char unload_heads_path[64];
	23
	24	int set_unload_heads_path(char *device)
	25	{
	26	char devname[64];
	27
	28	if (strlen(device) <= 5 \|\| strncmp(device, "/dev/", 5) != 0)
	29	return -EINVAL;
	30	strncpy(devname, device + 5, sizeof(devname));
	31
	32	snprintf(unload_heads_path, sizeof(unload_heads_path),
	33	"/sys/block/%s/device/unload_heads", devname);
	34	return 0;
	35	}
	36	int valid_disk(void)
	37	{
	38	int fd = open(unload_heads_path, O_RDONLY);
	39	if (fd < 0) {
	40	perror(unload_heads_path);
	41	return 0;
	42	}
	43
	44	close(fd);
	45	return 1;
	46	}
	47
ef2cfc79 PM	48	void write_int(char *path, int i)
	49	{
	50	char buf[1024];
	51	int fd = open(path, O_RDWR);
	52	if (fd < 0) {
	53	perror("open");
	54	exit(1);
	55	}
	56	sprintf(buf, "%d", i);
	57	if (write(fd, buf, strlen(buf)) != strlen(buf)) {
	58	perror("write");
	59	exit(1);
	60	}
	61	close(fd);
	62	}
	63
	64	void set_led(int on)
	65	{
	66	write_int("/sys/class/leds/hp::hddprotect/brightness", on);
	67	}
	68
	69	void protect(int seconds)
	70	{
be3990b7	71	write_int(unload_heads_path, seconds*1000);
ef2cfc79 PM	72	}
	73
	74	int on_ac(void)
	75	{
	76	// /sys/class/power_supply/AC0/online
	77	}
	78
	79	int lid_open(void)
	80	{
	81	// /proc/acpi/button/lid/LID/state
	82	}
	83
	84	void ignore_me(void)
	85	{
	86	protect(0);
	87	set_led(0);
ef2cfc79 PM	88	}
ef2cfc79 PM	89
be3990b7	90	int main(int argc, char **argv)
ef2cfc79	91	{
b519c15d	92	int fd, ret;
2bace8b9	93	struct sched_param param;
ef2cfc79	94
be3990b7 FP	95	if (argc == 1)
	96	ret = set_unload_heads_path("/dev/sda");
	97	else if (argc == 2)
	98	ret = set_unload_heads_path(argv[1]);
	99	else
	100	ret = -EINVAL;
	101
	102	if (ret \|\| !valid_disk()) {
	103	fprintf(stderr, "usage: %s <device> (default: /dev/sda)\n",
	104	argv[0]);
	105	exit(1);
	106	}
	107
b519c15d FP	108	fd = open("/dev/freefall", O_RDONLY);
b519c15d FP	109	if (fd < 0) {
be3990b7	110	perror("/dev/freefall");
b519c15d FP	111	return EXIT_FAILURE;
b519c15d FP	112	}
ef2cfc79	113
2bace8b9 CT	114	daemon(0, 0);
	115	param.sched_priority = sched_get_priority_max(SCHED_FIFO);
	116	sched_setscheduler(0, SCHED_FIFO, &param);
	117	mlockall(MCL_CURRENT\|MCL_FUTURE);
	118
ef2cfc79 PM	119	signal(SIGALRM, ignore_me);
ef2cfc79 PM	120
b519c15d FP	121	for (;;) {
	122	unsigned char count;
	123
	124	ret = read(fd, &count, sizeof(count));
	125	alarm(0);
	126	if ((ret == -1) && (errno == EINTR)) {
	127	/* Alarm expired, time to unpark the heads */
	128	continue;
	129	}
	130
	131	if (ret != sizeof(count)) {
	132	perror("read");
	133	break;
	134	}
	135
	136	protect(21);
	137	set_led(1);
	138	if (1 \|\| on_ac() \|\| lid_open())
	139	alarm(2);
	140	else
	141	alarm(20);
	142	}
ef2cfc79	143
b519c15d FP	144	close(fd);
b519c15d FP	145	return EXIT_SUCCESS;
ef2cfc79	146	}