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/* APM emulation layer for PowerMac
*
* Copyright 2001 Benjamin Herrenschmidt (benh@kernel.crashing.org)
*
* Lots of code inherited from apm.c, see appropriate notice in
* arch/i386/kernel/apm.c
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2, or (at your option) any
* later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
*
*/
#include <linux/config.h>
#include <linux/module.h>
#include <linux/poll.h>
#include <linux/types.h>
#include <linux/stddef.h>
#include <linux/timer.h>
#include <linux/fcntl.h>
#include <linux/slab.h>
#include <linux/stat.h>
#include <linux/proc_fs.h>
#include <linux/miscdevice.h>
#include <linux/apm_bios.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/pm.h>
#include <linux/kernel.h>
#include <linux/smp_lock.h>
#include <linux/adb.h>
#include <linux/pmu.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include <asm/machdep.h>
#undef DEBUG
#ifdef DEBUG
#define DBG(args...) printk(KERN_DEBUG args)
//#define DBG(args...) xmon_printf(args)
#else
#define DBG(args...) do { } while (0)
#endif
/*
* The apm_bios device is one of the misc char devices.
* This is its minor number.
*/
#define APM_MINOR_DEV 134
/*
* Maximum number of events stored
*/
#define APM_MAX_EVENTS 20
#define FAKE_APM_BIOS_VERSION 0x0101
#define APM_USER_NOTIFY_TIMEOUT (5*HZ)
/*
* The per-file APM data
*/
struct apm_user {
int magic;
struct apm_user * next;
int suser: 1;
int suspend_waiting: 1;
int suspends_pending;
int suspends_read;
int event_head;
int event_tail;
apm_event_t events[APM_MAX_EVENTS];
};
/*
* The magic number in apm_user
*/
#define APM_BIOS_MAGIC 0x4101
/*
* Local variables
*/
static int suspends_pending;
static DECLARE_WAIT_QUEUE_HEAD(apm_waitqueue);
static DECLARE_WAIT_QUEUE_HEAD(apm_suspend_waitqueue);
static struct apm_user * user_list;
static int apm_notify_sleep(struct pmu_sleep_notifier *self, int when);
static struct pmu_sleep_notifier apm_sleep_notifier = {
apm_notify_sleep,
SLEEP_LEVEL_USERLAND,
};
static char driver_version[] = "0.5"; /* no spaces */
#ifdef DEBUG
static char * apm_event_name[] = {
"system standby",
"system suspend",
"normal resume",
"critical resume",
"low battery",
"power status change",
"update time",
"critical suspend",
"user standby",
"user suspend",
"system standby resume",
"capabilities change"
};
#define NR_APM_EVENT_NAME \
(sizeof(apm_event_name) / sizeof(apm_event_name[0]))
#endif
static int queue_empty(struct apm_user *as)
{
return as->event_head == as->event_tail;
}
static apm_event_t get_queued_event(struct apm_user *as)
{
as->event_tail = (as->event_tail + 1) % APM_MAX_EVENTS;
return as->events[as->event_tail];
}
static void queue_event(apm_event_t event, struct apm_user *sender)
{
struct apm_user * as;
DBG("apm_emu: queue_event(%s)\n", apm_event_name[event-1]);
if (user_list == NULL)
return;
for (as = user_list; as != NULL; as = as->next) {
if (as == sender)
continue;
as->event_head = (as->event_head + 1) % APM_MAX_EVENTS;
if (as->event_head == as->event_tail) {
static int notified;
if (notified++ == 0)
printk(KERN_ERR "apm_emu: an event queue overflowed\n");
as->event_tail = (as->event_tail + 1) % APM_MAX_EVENTS;
}
as->events[as->event_head] = event;
if (!as->suser)
continue;
switch (event) {
case APM_SYS_SUSPEND:
case APM_USER_SUSPEND:
as->suspends_pending++;
suspends_pending++;
break;
case APM_NORMAL_RESUME:
as->suspend_waiting = 0;
break;
}
}
wake_up_interruptible(&apm_waitqueue);
}
static int check_apm_user(struct apm_user *as, const char *func)
{
if ((as == NULL) || (as->magic != APM_BIOS_MAGIC)) {
printk(KERN_ERR "apm_emu: %s passed bad filp\n", func);
return 1;
}
return 0;
}
static ssize_t do_read(struct file *fp, char *buf, size_t count, loff_t *ppos)
{
struct apm_user * as;
int i;
apm_event_t event;
DECLARE_WAITQUEUE(wait, current);
as = fp->private_data;
if (check_apm_user(as, "read"))
return -EIO;
if (count < sizeof(apm_event_t))
return -EINVAL;
if (queue_empty(as)) {
if (fp->f_flags & O_NONBLOCK)
return -EAGAIN;
add_wait_queue(&apm_waitqueue, &wait);
repeat:
set_current_state(TASK_INTERRUPTIBLE);
if (queue_empty(as) && !signal_pending(current)) {
schedule();
goto repeat;
}
set_current_state(TASK_RUNNING);
remove_wait_queue(&apm_waitqueue, &wait);
}
i = count;
while ((i >= sizeof(event)) && !queue_empty(as)) {
event = get_queued_event(as);
DBG("apm_emu: do_read, returning: %s\n", apm_event_name[event-1]);
if (copy_to_user(buf, &event, sizeof(event))) {
if (i < count)
break;
return -EFAULT;
}
switch (event) {
case APM_SYS_SUSPEND:
case APM_USER_SUSPEND:
as->suspends_read++;
break;
}
buf += sizeof(event);
i -= sizeof(event);
}
if (i < count)
return count - i;
if (signal_pending(current))
return -ERESTARTSYS;
return 0;
}
static unsigned int do_poll(struct file *fp, poll_table * wait)
{
struct apm_user * as;
as = fp->private_data;
if (check_apm_user(as, "poll"))
return 0;
poll_wait(fp, &apm_waitqueue, wait);
if (!queue_empty(as))
return POLLIN | POLLRDNORM;
return 0;
}
static int do_ioctl(struct inode * inode, struct file *filp,
u_int cmd, u_long arg)
{
struct apm_user * as;
DECLARE_WAITQUEUE(wait, current);
as = filp->private_data;
if (check_apm_user(as, "ioctl"))
return -EIO;
if (!as->suser)
return -EPERM;
switch (cmd) {
case APM_IOC_SUSPEND:
/* If a suspend message was sent to userland, we
* consider this as a confirmation message
*/
if (as->suspends_read > 0) {
as->suspends_read--;
as->suspends_pending--;
suspends_pending--;
} else {
// Route to PMU suspend ?
break;
}
as->suspend_waiting = 1;
add_wait_queue(&apm_waitqueue, &wait);
DBG("apm_emu: ioctl waking up sleep waiter !\n");
wake_up(&apm_suspend_waitqueue);
mb();
while(as->suspend_waiting && !signal_pending(current)) {
set_current_state(TASK_INTERRUPTIBLE);
schedule();
}
set_current_state(TASK_RUNNING);
remove_wait_queue(&apm_waitqueue, &wait);
break;
default:
return -EINVAL;
}
return 0;
}
static int do_release(struct inode * inode, struct file * filp)
{
struct apm_user * as;
as = filp->private_data;
if (check_apm_user(as, "release"))
return 0;
filp->private_data = NULL;
lock_kernel();
if (as->suspends_pending > 0) {
suspends_pending -= as->suspends_pending;
if (suspends_pending <= 0)
wake_up(&apm_suspend_waitqueue);
}
if (user_list == as)
user_list = as->next;
else {
struct apm_user * as1;
for (as1 = user_list;
(as1 != NULL) && (as1->next != as);
as1 = as1->next)
;
if (as1 == NULL)
printk(KERN_ERR "apm: filp not in user list\n");
else
as1->next = as->next;
}
unlock_kernel();
kfree(as);
return 0;
}
static int do_open(struct inode * inode, struct file * filp)
{
struct apm_user * as;
as = (struct apm_user *)kmalloc(sizeof(*as), GFP_KERNEL);
if (as == NULL) {
printk(KERN_ERR "apm: cannot allocate struct of size %d bytes\n",
sizeof(*as));
return -ENOMEM;
}
as->magic = APM_BIOS_MAGIC;
as->event_tail = as->event_head = 0;
as->suspends_pending = 0;
as->suspends_read = 0;
/*
* XXX - this is a tiny bit broken, when we consider BSD
* process accounting. If the device is opened by root, we
* instantly flag that we used superuser privs. Who knows,
* we might close the device immediately without doing a
* privileged operation -- cevans
*/
as->suser = capable(CAP_SYS_ADMIN);
as->next = user_list;
user_list = as;
filp->private_data = as;
DBG("apm_emu: opened by %s, suser: %d\n", current->comm, (int)as->suser);
return 0;
}
/* Wait for all clients to ack the suspend request. APM API
* doesn't provide a way to NAK, but this could be added
* here.
*/
static int wait_all_suspend(void)
{
DECLARE_WAITQUEUE(wait, current);
add_wait_queue(&apm_suspend_waitqueue, &wait);
DBG("apm_emu: wait_all_suspend(), suspends_pending: %d\n", suspends_pending);
while(suspends_pending > 0) {
set_current_state(TASK_UNINTERRUPTIBLE);
schedule();
}
set_current_state(TASK_RUNNING);
remove_wait_queue(&apm_suspend_waitqueue, &wait);
DBG("apm_emu: wait_all_suspend() - complete !\n");
return 1;
}
static int apm_notify_sleep(struct pmu_sleep_notifier *self, int when)
{
switch(when) {
case PBOOK_SLEEP_REQUEST:
queue_event(APM_SYS_SUSPEND, NULL);
if (!wait_all_suspend())
return PBOOK_SLEEP_REFUSE;
break;
case PBOOK_SLEEP_REJECT:
case PBOOK_WAKE:
queue_event(APM_NORMAL_RESUME, NULL);
break;
}
return PBOOK_SLEEP_OK;
}
#define APM_CRITICAL 10
#define APM_LOW 30
static int apm_emu_get_info(char *buf, char **start, off_t fpos, int length)
{
/* Arguments, with symbols from linux/apm_bios.h. Information is
from the Get Power Status (0x0a) call unless otherwise noted.
0) Linux driver version (this will change if format changes)
1) APM BIOS Version. Usually 1.0, 1.1 or 1.2.
2) APM flags from APM Installation Check (0x00):
bit 0: APM_16_BIT_SUPPORT
bit 1: APM_32_BIT_SUPPORT
bit 2: APM_IDLE_SLOWS_CLOCK
bit 3: APM_BIOS_DISABLED
bit 4: APM_BIOS_DISENGAGED
3) AC line status
0x00: Off-line
0x01: On-line
0x02: On backup power (BIOS >= 1.1 only)
0xff: Unknown
4) Battery status
0x00: High
0x01: Low
0x02: Critical
0x03: Charging
0x04: Selected battery not present (BIOS >= 1.2 only)
0xff: Unknown
5) Battery flag
bit 0: High
bit 1: Low
bit 2: Critical
bit 3: Charging
bit 7: No system battery
0xff: Unknown
6) Remaining battery life (percentage of charge):
0-100: valid
-1: Unknown
7) Remaining battery life (time units):
Number of remaining minutes or seconds
-1: Unknown
8) min = minutes; sec = seconds */
unsigned short ac_line_status = 0xff;
unsigned short battery_status = 0xff;
unsigned short battery_flag = 0xff;
int percentage = -1;
int time_units = -1;
int real_count = 0;
int i;
char * p = buf;
ac_line_status = ((pmu_power_flags & PMU_PWR_AC_PRESENT) != 0);
for (i=0; i<pmu_battery_count; i++) {
if (percentage < 0)
percentage = 0;
if (time_units < 0)
time_units = 0;
if (pmu_batteries[i].flags & PMU_BATT_PRESENT) {
percentage += (pmu_batteries[i].charge * 100) /
pmu_batteries[i].max_charge;
/* hrm... should we provide the remaining charge
* time when AC is plugged ? If yes, just remove
* that test --BenH
*/
if (!ac_line_status)
time_units += pmu_batteries[i].time_remaining / 60;
real_count++;
if (!(pmu_batteries[i].flags & PMU_BATT_CHARGING))
battery_flag &= ~0x08;
}
}
if (real_count) {
percentage /= real_count;
if (battery_flag & 0x08) {
battery_status = 0x03;
battery_flag = 0x08;
} else if (percentage <= APM_CRITICAL) {
battery_status = 0x02;
battery_flag = 0x04;
} else if (percentage <= APM_LOW) {
battery_status = 0x01;
battery_flag = 0x02;
} else {
battery_status = 0x00;
battery_flag = 0x01;
}
}
p += sprintf(p, "%s %d.%d 0x%02x 0x%02x 0x%02x 0x%02x %d%% %d %s\n",
driver_version,
(FAKE_APM_BIOS_VERSION >> 8) & 0xff,
FAKE_APM_BIOS_VERSION & 0xff,
0,
ac_line_status,
battery_status,
battery_flag,
percentage,
time_units,
"min");
return p - buf;
}
static struct file_operations apm_bios_fops = {
owner: THIS_MODULE,
read: do_read,
poll: do_poll,
ioctl: do_ioctl,
open: do_open,
release: do_release,
};
static struct miscdevice apm_device = {
APM_MINOR_DEV,
"apm_bios",
&apm_bios_fops
};
static int __init apm_emu_init(void)
{
struct proc_dir_entry *apm_proc;
if (sys_ctrler != SYS_CTRLER_PMU) {
printk(KERN_INFO "apm_emu: Requires a machine with a PMU.\n");
return -ENODEV;
}
apm_proc = create_proc_info_entry("apm", 0, NULL, apm_emu_get_info);
if (apm_proc)
SET_MODULE_OWNER(apm_proc);
misc_register(&apm_device);
pmu_register_sleep_notifier(&apm_sleep_notifier);
printk(KERN_INFO "apm_emu: APM Emulation %s initialized.\n", driver_version);
return 0;
}
static void __exit apm_emu_exit(void)
{
pmu_unregister_sleep_notifier(&apm_sleep_notifier);
misc_deregister(&apm_device);
remove_proc_entry("apm", NULL);
printk(KERN_INFO "apm_emu: APM Emulation removed.\n");
}
module_init(apm_emu_init);
module_exit(apm_emu_exit);
MODULE_AUTHOR("Benjamin Herrenschmidt");
MODULE_DESCRIPTION("APM emulation layer for PowerMac");
MODULE_LICENSE("GPL");
EXPORT_NO_SYMBOLS;
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