1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* -*- linux-c -*-
4  * Copyright 1994-2001 Stephen Rothwell (sfr@canb.auug.org.au)
16  *    (Thanks to Ulrich Windl <Ulrich.Windl@rz.uni-regensburg.de>)
43  *    1.1: support user-space standby and suspend, power off after system
46  *         is only incorrect by 30-60mS (vs. 1S previously) (Gabor J. Toth
48  *         screen-blanking and gpm (Stephen Rothwell); Linux 1.99.4
63  *                   <echter@informatik.uni-rostock.de>
109  *         <Walter.Hofmann@physik.stud.uni-erlangen.de>).
120  *         Remove smp-power-off. SMP users must now specify
121  *         "apm=power-off" on the kernel command line. Suggested
130  *         Fix the Thinkpad (again) :-( (CONFIG_APM_IGNORE_MULTIPLE_SUSPENDS
139  *         <tmh@magenta-logic.com> and <zlatko@iskon.hr>) modified by sfr.
145  *         Changed to use the sysrq-register hack for registering the
156  *         calling it - instead idle. (Alan Cox <alan@lxorguk.ukuu.org.uk>)
180  *   Intel Order Number 241704-001.  Microsoft Part Number 781-110-X01.
234 #include <asm/nospec-branch.h>
241  * The apm_bios device is one of the misc char devices.
250  *	    [no-]allow[-_]ints		allow interrupts during BIOS calls
251  *	    [no-]broken[-_]psr		BIOS has a broken GetPowerStatus call
252  *	    [no-]realmode[-_]power[-_]off	switch to real mode before
254  *	    [no-]debug			log some debugging messages
255  *	    [no-]power[-_]off		power off on shutdown
256  *	    [no-]smp			Use apm even on an SMP box
257  *	    bounce[-_]interval=<n>	number of ticks to ignore suspend
259  *          idle[-_]threshold=<n>       System idle percentage above which to
262  *          idle[-_]period=<n>          Period (in 1/100s of a second) over
277  * ?: AcerNote-950: oops on reading /proc/apm - workaround is a WIP
301  * Define to re-initialize the interrupt 0 timer to 100 Hz after a suspend.
329  * The per-file APM data
402 static int apm_disabled = -1;
429 			(unsigned long)__va(0x400UL), PAGE_SIZE - 0x400 - 1);
487  *	apm_error	-	display an APM error
518  * for the rest of the kernel.  And it will be very obvious!  :-) Doing
575 	/* Error: -ENOMEM, or bits 8-15 of eax */
580  *	__apm_bios_call - Make an APM BIOS 32bit call
588  *	code is returned in AH (bits 8-15 of eax) and this function
589  *	returns non-zero.
611 	apm_bios_call_asm(call->func, call->ebx, call->ecx,  in __apm_bios_call()
612 			  &call->eax, &call->ebx, &call->ecx, &call->edx,  in __apm_bios_call()
613 			  &call->esi);  in __apm_bios_call()
620 	return call->eax & 0xff;  in __apm_bios_call()
638 	/* work_on_cpu can fail with -ENOMEM */  in on_cpu0()
640 		call->err = ret;  in on_cpu0()
642 		call->err = (call->eax >> 8) & 0xff;  in on_cpu0()
648  *	apm_bios_call	-	Make an APM BIOS 32bit call (on CPU 0)
659  *	__apm_bios_call_simple - Make an APM BIOS 32bit call (on CPU 0)
664  *	(bits 8-15 of eax) and this function returns non-zero (it can
665  *	also return -ENOMEM). This is used for simpler BIOS operations.
689 	error = apm_bios_call_simple_asm(call->func, call->ebx, call->ecx,  in __apm_bios_call_simple()
690 					 &call->eax);  in __apm_bios_call_simple()
700  *	apm_bios_call_simple	-	make a simple APM BIOS 32bit call
709  *	and this function returns non-zero. This is used for simpler
730  *	apm_driver_version	-	APM driver version
757  *	apm_get_event	-	get an APM event from the BIOS
791  *	set_power_state	-	set the power management state
815  *	set_system_power_state - set system wide power state
827  *	apm_do_idle	-	perform power saving
830  *	of the OS) idle. It returns -1 in the event that the BIOS refuses
860 		return -1;  in apm_do_idle()
867  *	apm_do_busy	-	inform the BIOS the CPU is busy
886  * power management - we probably want
893  * apm_cpu_idle		-	cpu idling for APM capable Linux
909 	unsigned int jiffies_since_last_check = jiffies - last_jiffies;  in apm_cpu_idle()
919 		idle_percentage = nsecs_to_jiffies(stime - last_stime);  in apm_cpu_idle()
946 					bucket--;  in apm_cpu_idle()
959 		jiffies_since_last_check = jiffies - last_jiffies;  in apm_cpu_idle()
971  *	apm_power_off	-	ask the BIOS to power off
994  *	apm_enable_power_management - enable BIOS APM power management
1019  *	apm_get_power_status	-	get current power state
1087  *	apm_engage_power_management	-	enable PM on a device
1118  *	apm_console_blank	-	blank the display
1166 	return as->event_head == as->event_tail;  in queue_empty()
1171 	if (++as->event_tail >= APM_MAX_EVENTS)  in get_queued_event()
1172 		as->event_tail = 0;  in get_queued_event()
1173 	return as->events[as->event_tail];  in get_queued_event()
1183 	for (as = user_list; as != NULL; as = as->next) {  in queue_event()
1184 		if ((as == sender) || (!as->reader))  in queue_event()
1186 		if (++as->event_head >= APM_MAX_EVENTS)  in queue_event()
1187 			as->event_head = 0;  in queue_event()
1189 		if (as->event_head == as->event_tail) {  in queue_event()
1194 			if (++as->event_tail >= APM_MAX_EVENTS)  in queue_event()
1195 				as->event_tail = 0;  in queue_event()
1197 		as->events[as->event_head] = event;  in queue_event()
1198 		if (!as->suser || !as->writer)  in queue_event()
1203 			as->suspends_pending++;  in queue_event()
1209 			as->standbys_pending++;  in queue_event()
1228 	outb_p(LATCH & 0xff, PIT_CH0);	/* LSB */  in reinit_timer()
1230 	outb_p(LATCH >> 8, PIT_CH0);	/* MSB */  in reinit_timer()
1261 	err = (err == APM_SUCCESS) ? 0 : -EIO;  in suspend()
1271 	for (as = user_list; as != NULL; as = as->next) {  in suspend()
1272 		as->suspend_wait = 0;  in suspend()
1273 		as->suspend_result = err;  in suspend()
1330 				       apm_event_name[event - 1]);  in check_events()
1416 		    (pending_count-- <= 0)) {  in apm_event_handler()
1455 	if (as == NULL || as->magic != APM_BIOS_MAGIC) {  in check_apm_user()
1468 	as = fp->private_data;  in do_read()
1470 		return -EIO;  in do_read()
1472 		return -EINVAL;  in do_read()
1473 	if ((queue_empty(as)) && (fp->f_flags & O_NONBLOCK))  in do_read()
1474 		return -EAGAIN;  in do_read()
1482 			return -EFAULT;  in do_read()
1487 			as->suspends_read++;  in do_read()
1492 			as->standbys_read++;  in do_read()
1496 		i -= sizeof(event);  in do_read()
1499 		return count - i;  in do_read()
1501 		return -ERESTARTSYS;  in do_read()
1509 	as = fp->private_data;  in do_poll()
1523 	as = filp->private_data;  in do_ioctl()
1525 		return -EIO;  in do_ioctl()
1526 	if (!as->suser || !as->writer)  in do_ioctl()
1527 		return -EPERM;  in do_ioctl()
1531 		if (as->standbys_read > 0) {  in do_ioctl()
1532 			as->standbys_read--;  in do_ioctl()
1533 			as->standbys_pending--;  in do_ioctl()
1534 			standbys_pending--;  in do_ioctl()
1543 		if (as->suspends_read > 0) {  in do_ioctl()
1544 			as->suspends_read--;  in do_ioctl()
1545 			as->suspends_pending--;  in do_ioctl()
1546 			suspends_pending--;  in do_ioctl()
1553 			as->suspend_wait = 1;  in do_ioctl()
1556 					as->suspend_wait == 0);  in do_ioctl()
1557 			ret = as->suspend_result;  in do_ioctl()
1561 		return -ENOTTY;  in do_ioctl()
1570 	as = filp->private_data;  in do_release()
1573 	filp->private_data = NULL;  in do_release()
1574 	if (as->standbys_pending > 0) {  in do_release()
1575 		standbys_pending -= as->standbys_pending;  in do_release()
1579 	if (as->suspends_pending > 0) {  in do_release()
1580 		suspends_pending -= as->suspends_pending;  in do_release()
1586 		user_list = as->next;  in do_release()
1591 		     (as1 != NULL) && (as1->next != as);  in do_release()
1592 		     as1 = as1->next)  in do_release()
1597 			as1->next = as->next;  in do_release()
1610 		return -ENOMEM;  in do_open()
1612 	as->magic = APM_BIOS_MAGIC;  in do_open()
1613 	as->event_tail = as->event_head = 0;  in do_open()
1614 	as->suspends_pending = as->standbys_pending = 0;  in do_open()
1615 	as->suspends_read = as->standbys_read = 0;  in do_open()
1617 	 * XXX - this is a tiny bit broken, when we consider BSD  in do_open()
1621 	 * privileged operation -- cevans  in do_open()
1623 	as->suser = capable(CAP_SYS_ADMIN);  in do_open()
1624 	as->writer = (filp->f_mode & FMODE_WRITE) == FMODE_WRITE;  in do_open()
1625 	as->reader = (filp->f_mode & FMODE_READ) == FMODE_READ;  in do_open()
1627 	as->next = user_list;  in do_open()
1630 	filp->private_data = as;  in do_open()
1644 	int		percentage     = -1;  in proc_apm_show()
1645 	int             time_units     = -1;  in proc_apm_show()
1675 	      0x00: Off-line  in proc_apm_show()
1676 	      0x01: On-line  in proc_apm_show()
1694 	      0-100: valid  in proc_apm_show()
1695 	      -1: Unknown  in proc_apm_show()
1698 	      -1: Unknown  in proc_apm_show()
1725 	/* 2002/08/01 - WT  in apm()
1727 	 * on SMP systems in case of "apm=power-off" mode. Seen on ASUS A7M266D.  in apm()
1766 			return -1;  in apm()
1776 			return -1;  in apm()
1864 		if ((strncmp(str, "bounce-interval=", 16) == 0) ||  in apm_setup()
1867 		if ((strncmp(str, "idle-threshold=", 15) == 0) ||  in apm_setup()
1870 		if ((strncmp(str, "idle-period=", 12) == 0) ||  in apm_setup()
1873 		invert = (strncmp(str, "no-", 3) == 0) ||  in apm_setup()
1879 		if ((strncmp(str, "power-off", 9) == 0) ||  in apm_setup()
1886 		if ((strncmp(str, "allow-ints", 10) == 0) ||  in apm_setup()
1889 		if ((strncmp(str, "broken-psr", 10) == 0) ||  in apm_setup()
1892 		if ((strncmp(str, "realmode-power-off", 18) == 0) ||  in apm_setup()
1925 	printk("%s\n", d->ident);  in print_if_true()
1936 	       "workaround hopefully not needed.\n", d->ident);  in broken_ps2_resume()
1946 		       "Using realmode poweroff only.\n", d->ident);  in set_realmode_power_off()
1957 		       "Enabling interrupts during APM calls.\n", d->ident);  in set_apm_ints()
1968 		       "Disabling APM.\n", d->ident);  in apm_is_horked()
1978 		       "Disabling APM.\n", d->ident);  in apm_is_horked_d850md()
1991 		       "Disabling APM idle calls.\n", d->ident);  in apm_likes_to_melt()
2000  *      [ Write BIOS Code ]<------
2002  *      < Does it Compile >----N--
2004  *	< Does it Boot Win98 >-N--
2034 		KERN_WARNING "IBM T23 - BIOS 1.03b+ and controller firmware 1.02+ may be needed for Linux APM.",
2075 			DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"),
2092 		apm_is_horked, "ABIT KX7-333[R]",
2094 			DMI_MATCH(DMI_BOARD_NAME, "VT8367-8233A (KX7-333[R])"), },
2102 		apm_is_horked, "Fujitsu-Siemens",
2117 		apm_is_horked, "Dell XPS-Z",
2120 			DMI_MATCH(DMI_PRODUCT_NAME, "XPS-Z"), },
2123 		apm_is_horked, "Sharp PC-PJ/AX",
2125 			DMI_MATCH(DMI_PRODUCT_NAME, "PC-PJ/AX"),
2146 	{	/* Handle problems with APM on Sony Vaio PCG-N505X(DE) */
2152 	{	/* Handle problems with APM on Sony Vaio PCG-N505VX */
2158 	{	/* Handle problems with APM on Sony Vaio PCG-XG29 */
2164 	{	/* Handle problems with APM on Sony Vaio PCG-Z600NE */
2170 	{	/* Handle problems with APM on Sony Vaio PCG-Z600NE */
2176 	{	/* Handle problems with APM on Sony Vaio PCG-Z600LEK(DE) */
2182 	{	/* Handle problems with APM on Sony Vaio PCG-Z505LS */
2188 	{	/* Handle problems with APM on Sony Vaio PCG-Z505LS */
2194 	{	/* Handle problems with APM on Sony Vaio PCG-Z505LS (with updated BIOS) */
2200 	{	/* Handle problems with APM on Sony Vaio PCG-F104K */
2207 	{	/* Handle problems with APM on Sony Vaio PCG-C1VN/C1VE */
2213 	{	/* Handle problems with APM on Sony Vaio PCG-C1VE */
2219 	{	/* Handle problems with APM on Sony Vaio PCG-C1VE */
2261 		return -ENODEV;  in apm_init()
2271 		return -ENODEV;  in apm_init()
2281 	if (apm_disabled != -1)  in apm_init()
2310 		return -ENODEV;  in apm_init()
2313 		pr_notice("disabled - APM is not SMP safe.\n");  in apm_init()
2315 		return -ENODEV;  in apm_init()
2320 		return -ENODEV;  in apm_init()
2352 		pr_err("disabled - Unable to start kernel thread\n");  in apm_init()
2362 		       "apm: disabled - APM is not SMP safe (power off active).\n");  in apm_init()
2372 		printk(KERN_WARNING "apm: Could not register misc device.\n");  in apm_init()