diff options
Diffstat (limited to 'arch/arm/kernel/apm.c')
| -rw-r--r-- | arch/arm/kernel/apm.c | 672 |
1 files changed, 0 insertions, 672 deletions
diff --git a/arch/arm/kernel/apm.c b/arch/arm/kernel/apm.c deleted file mode 100644 index 2c37b70b17ab..000000000000 --- a/arch/arm/kernel/apm.c +++ /dev/null @@ -1,672 +0,0 @@ -/* - * bios-less APM driver for ARM Linux - * Jamey Hicks <jamey@crl.dec.com> - * adapted from the APM BIOS driver for Linux by Stephen Rothwell (sfr@linuxcare.com) - * - * APM 1.2 Reference: - * Intel Corporation, Microsoft Corporation. Advanced Power Management - * (APM) BIOS Interface Specification, Revision 1.2, February 1996. - * - * [This document is available from Microsoft at: - * http://www.microsoft.com/hwdev/busbios/amp_12.htm] - */ -#include <linux/module.h> -#include <linux/poll.h> -#include <linux/slab.h> -#include <linux/proc_fs.h> -#include <linux/miscdevice.h> -#include <linux/apm_bios.h> -#include <linux/capability.h> -#include <linux/sched.h> -#include <linux/pm.h> -#include <linux/device.h> -#include <linux/kernel.h> -#include <linux/list.h> -#include <linux/init.h> -#include <linux/completion.h> -#include <linux/kthread.h> -#include <linux/delay.h> - -#include <asm/apm.h> /* apm_power_info */ -#include <asm/system.h> - -/* - * The apm_bios device is one of the misc char devices. - * This is its minor number. - */ -#define APM_MINOR_DEV 134 - -/* - * See Documentation/Config.help for the configuration options. - * - * Various options can be changed at boot time as follows: - * (We allow underscores for compatibility with the modules code) - * apm=on/off enable/disable APM - */ - -/* - * Maximum number of events stored - */ -#define APM_MAX_EVENTS 16 - -struct apm_queue { - unsigned int event_head; - unsigned int event_tail; - apm_event_t events[APM_MAX_EVENTS]; -}; - -/* - * The per-file APM data - */ -struct apm_user { - struct list_head list; - - unsigned int suser: 1; - unsigned int writer: 1; - unsigned int reader: 1; - - int suspend_result; - unsigned int suspend_state; -#define SUSPEND_NONE 0 /* no suspend pending */ -#define SUSPEND_PENDING 1 /* suspend pending read */ -#define SUSPEND_READ 2 /* suspend read, pending ack */ -#define SUSPEND_ACKED 3 /* suspend acked */ -#define SUSPEND_WAIT 4 /* waiting for suspend */ -#define SUSPEND_DONE 5 /* suspend completed */ - - struct apm_queue queue; -}; - -/* - * Local variables - */ -static int suspends_pending; -static int apm_disabled; -static struct task_struct *kapmd_tsk; - -static DECLARE_WAIT_QUEUE_HEAD(apm_waitqueue); -static DECLARE_WAIT_QUEUE_HEAD(apm_suspend_waitqueue); - -/* - * This is a list of everyone who has opened /dev/apm_bios - */ -static DECLARE_RWSEM(user_list_lock); -static LIST_HEAD(apm_user_list); - -/* - * kapmd info. kapmd provides us a process context to handle - * "APM" events within - specifically necessary if we're going - * to be suspending the system. - */ -static DECLARE_WAIT_QUEUE_HEAD(kapmd_wait); -static DEFINE_SPINLOCK(kapmd_queue_lock); -static struct apm_queue kapmd_queue; - -static DEFINE_MUTEX(state_lock); - -static const char driver_version[] = "1.13"; /* no spaces */ - - - -/* - * Compatibility cruft until the IPAQ people move over to the new - * interface. - */ -static void __apm_get_power_status(struct apm_power_info *info) -{ -} - -/* - * This allows machines to provide their own "apm get power status" function. - */ -void (*apm_get_power_status)(struct apm_power_info *) = __apm_get_power_status; -EXPORT_SYMBOL(apm_get_power_status); - - -/* - * APM event queue management. - */ -static inline int queue_empty(struct apm_queue *q) -{ - return q->event_head == q->event_tail; -} - -static inline apm_event_t queue_get_event(struct apm_queue *q) -{ - q->event_tail = (q->event_tail + 1) % APM_MAX_EVENTS; - return q->events[q->event_tail]; -} - -static void queue_add_event(struct apm_queue *q, apm_event_t event) -{ - q->event_head = (q->event_head + 1) % APM_MAX_EVENTS; - if (q->event_head == q->event_tail) { - static int notified; - - if (notified++ == 0) - printk(KERN_ERR "apm: an event queue overflowed\n"); - q->event_tail = (q->event_tail + 1) % APM_MAX_EVENTS; - } - q->events[q->event_head] = event; -} - -static void queue_event(apm_event_t event) -{ - struct apm_user *as; - - down_read(&user_list_lock); - list_for_each_entry(as, &apm_user_list, list) { - if (as->reader) - queue_add_event(&as->queue, event); - } - up_read(&user_list_lock); - wake_up_interruptible(&apm_waitqueue); -} - -/* - * queue_suspend_event - queue an APM suspend event. - * - * Check that we're in a state where we can suspend. If not, - * return -EBUSY. Otherwise, queue an event to all "writer" - * users. If there are no "writer" users, return '1' to - * indicate that we can immediately suspend. - */ -static int queue_suspend_event(apm_event_t event, struct apm_user *sender) -{ - struct apm_user *as; - int ret = 1; - - mutex_lock(&state_lock); - down_read(&user_list_lock); - - /* - * If a thread is still processing, we can't suspend, so reject - * the request. - */ - list_for_each_entry(as, &apm_user_list, list) { - if (as != sender && as->reader && as->writer && as->suser && - as->suspend_state != SUSPEND_NONE) { - ret = -EBUSY; - goto out; - } - } - - list_for_each_entry(as, &apm_user_list, list) { - if (as != sender && as->reader && as->writer && as->suser) { - as->suspend_state = SUSPEND_PENDING; - suspends_pending++; - queue_add_event(&as->queue, event); - ret = 0; - } - } - out: - up_read(&user_list_lock); - mutex_unlock(&state_lock); - wake_up_interruptible(&apm_waitqueue); - return ret; -} - -static void apm_suspend(void) -{ - struct apm_user *as; - int err = pm_suspend(PM_SUSPEND_MEM); - - /* - * Anyone on the APM queues will think we're still suspended. - * Send a message so everyone knows we're now awake again. - */ - queue_event(APM_NORMAL_RESUME); - - /* - * Finally, wake up anyone who is sleeping on the suspend. - */ - mutex_lock(&state_lock); - down_read(&user_list_lock); - list_for_each_entry(as, &apm_user_list, list) { - if (as->suspend_state == SUSPEND_WAIT || - as->suspend_state == SUSPEND_ACKED) { - as->suspend_result = err; - as->suspend_state = SUSPEND_DONE; - } - } - up_read(&user_list_lock); - mutex_unlock(&state_lock); - - wake_up(&apm_suspend_waitqueue); -} - -static ssize_t apm_read(struct file *fp, char __user *buf, size_t count, loff_t *ppos) -{ - struct apm_user *as = fp->private_data; - apm_event_t event; - int i = count, ret = 0; - - if (count < sizeof(apm_event_t)) - return -EINVAL; - - if (queue_empty(&as->queue) && fp->f_flags & O_NONBLOCK) - return -EAGAIN; - - wait_event_interruptible(apm_waitqueue, !queue_empty(&as->queue)); - - while ((i >= sizeof(event)) && !queue_empty(&as->queue)) { - event = queue_get_event(&as->queue); - - ret = -EFAULT; - if (copy_to_user(buf, &event, sizeof(event))) - break; - - mutex_lock(&state_lock); - if (as->suspend_state == SUSPEND_PENDING && - (event == APM_SYS_SUSPEND || event == APM_USER_SUSPEND)) - as->suspend_state = SUSPEND_READ; - mutex_unlock(&state_lock); - - buf += sizeof(event); - i -= sizeof(event); - } - - if (i < count) - ret = count - i; - - return ret; -} - -static unsigned int apm_poll(struct file *fp, poll_table * wait) -{ - struct apm_user *as = fp->private_data; - - poll_wait(fp, &apm_waitqueue, wait); - return queue_empty(&as->queue) ? 0 : POLLIN | POLLRDNORM; -} - -/* - * apm_ioctl - handle APM ioctl - * - * APM_IOC_SUSPEND - * This IOCTL is overloaded, and performs two functions. It is used to: - * - initiate a suspend - * - acknowledge a suspend read from /dev/apm_bios. - * Only when everyone who has opened /dev/apm_bios with write permission - * has acknowledge does the actual suspend happen. - */ -static int -apm_ioctl(struct inode * inode, struct file *filp, u_int cmd, u_long arg) -{ - struct apm_user *as = filp->private_data; - unsigned long flags; - int err = -EINVAL; - - if (!as->suser || !as->writer) - return -EPERM; - - switch (cmd) { - case APM_IOC_SUSPEND: - mutex_lock(&state_lock); - - as->suspend_result = -EINTR; - - if (as->suspend_state == SUSPEND_READ) { - int pending; - - /* - * If we read a suspend command from /dev/apm_bios, - * then the corresponding APM_IOC_SUSPEND ioctl is - * interpreted as an acknowledge. - */ - as->suspend_state = SUSPEND_ACKED; - suspends_pending--; - pending = suspends_pending == 0; - mutex_unlock(&state_lock); - - /* - * If there are no further acknowledges required, - * suspend the system. - */ - if (pending) - apm_suspend(); - - /* - * Wait for the suspend/resume to complete. If there - * are pending acknowledges, we wait here for them. - * - * Note: we need to ensure that the PM subsystem does - * not kick us out of the wait when it suspends the - * threads. - */ - flags = current->flags; - current->flags |= PF_NOFREEZE; - - wait_event(apm_suspend_waitqueue, - as->suspend_state == SUSPEND_DONE); - } else { - as->suspend_state = SUSPEND_WAIT; - mutex_unlock(&state_lock); - - /* - * Otherwise it is a request to suspend the system. - * Queue an event for all readers, and expect an - * acknowledge from all writers who haven't already - * acknowledged. - */ - err = queue_suspend_event(APM_USER_SUSPEND, as); - if (err < 0) { - /* - * Avoid taking the lock here - this - * should be fine. - */ - as->suspend_state = SUSPEND_NONE; - break; - } - - if (err > 0) - apm_suspend(); - - /* - * Wait for the suspend/resume to complete. If there - * are pending acknowledges, we wait here for them. - * - * Note: we need to ensure that the PM subsystem does - * not kick us out of the wait when it suspends the - * threads. - */ - flags = current->flags; - current->flags |= PF_NOFREEZE; - - wait_event_interruptible(apm_suspend_waitqueue, - as->suspend_state == SUSPEND_DONE); - } - - current->flags = flags; - - mutex_lock(&state_lock); - err = as->suspend_result; - as->suspend_state = SUSPEND_NONE; - mutex_unlock(&state_lock); - break; - } - - return err; -} - -static int apm_release(struct inode * inode, struct file * filp) -{ - struct apm_user *as = filp->private_data; - int pending = 0; - - filp->private_data = NULL; - - down_write(&user_list_lock); - list_del(&as->list); - up_write(&user_list_lock); - - /* - * We are now unhooked from the chain. As far as new - * events are concerned, we no longer exist. However, we - * need to balance suspends_pending, which means the - * possibility of sleeping. - */ - mutex_lock(&state_lock); - if (as->suspend_state != SUSPEND_NONE) { - suspends_pending -= 1; - pending = suspends_pending == 0; - } - mutex_unlock(&state_lock); - if (pending) - apm_suspend(); - - kfree(as); - return 0; -} - -static int apm_open(struct inode * inode, struct file * filp) -{ - struct apm_user *as; - - as = kzalloc(sizeof(*as), GFP_KERNEL); - if (as) { - /* - * 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->writer = (filp->f_mode & FMODE_WRITE) == FMODE_WRITE; - as->reader = (filp->f_mode & FMODE_READ) == FMODE_READ; - - down_write(&user_list_lock); - list_add(&as->list, &apm_user_list); - up_write(&user_list_lock); - - filp->private_data = as; - } - - return as ? 0 : -ENOMEM; -} - -static struct file_operations apm_bios_fops = { - .owner = THIS_MODULE, - .read = apm_read, - .poll = apm_poll, - .ioctl = apm_ioctl, - .open = apm_open, - .release = apm_release, -}; - -static struct miscdevice apm_device = { - .minor = APM_MINOR_DEV, - .name = "apm_bios", - .fops = &apm_bios_fops -}; - - -#ifdef CONFIG_PROC_FS -/* - * Arguments, with symbols from linux/apm_bios.h. - * - * 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 - */ -static int apm_get_info(char *buf, char **start, off_t fpos, int length) -{ - struct apm_power_info info; - char *units; - int ret; - - info.ac_line_status = 0xff; - info.battery_status = 0xff; - info.battery_flag = 0xff; - info.battery_life = -1; - info.time = -1; - info.units = -1; - - if (apm_get_power_status) - apm_get_power_status(&info); - - switch (info.units) { - default: units = "?"; break; - case 0: units = "min"; break; - case 1: units = "sec"; break; - } - - ret = sprintf(buf, "%s 1.2 0x%02x 0x%02x 0x%02x 0x%02x %d%% %d %s\n", - driver_version, APM_32_BIT_SUPPORT, - info.ac_line_status, info.battery_status, - info.battery_flag, info.battery_life, - info.time, units); - - return ret; -} -#endif - -static int kapmd(void *arg) -{ - do { - apm_event_t event; - int ret; - - wait_event_interruptible(kapmd_wait, - !queue_empty(&kapmd_queue) || kthread_should_stop()); - - if (kthread_should_stop()) - break; - - spin_lock_irq(&kapmd_queue_lock); - event = 0; - if (!queue_empty(&kapmd_queue)) - event = queue_get_event(&kapmd_queue); - spin_unlock_irq(&kapmd_queue_lock); - - switch (event) { - case 0: - break; - - case APM_LOW_BATTERY: - case APM_POWER_STATUS_CHANGE: - queue_event(event); - break; - - case APM_USER_SUSPEND: - case APM_SYS_SUSPEND: - ret = queue_suspend_event(event, NULL); - if (ret < 0) { - /* - * We were busy. Try again in 50ms. - */ - queue_add_event(&kapmd_queue, event); - msleep(50); - } - if (ret > 0) - apm_suspend(); - break; - - case APM_CRITICAL_SUSPEND: - apm_suspend(); - break; - } - } while (1); - - return 0; -} - -static int __init apm_init(void) -{ - int ret; - - if (apm_disabled) { - printk(KERN_NOTICE "apm: disabled on user request.\n"); - return -ENODEV; - } - - kapmd_tsk = kthread_create(kapmd, NULL, "kapmd"); - if (IS_ERR(kapmd_tsk)) { - ret = PTR_ERR(kapmd_tsk); - kapmd_tsk = NULL; - return ret; - } - kapmd_tsk->flags |= PF_NOFREEZE; - wake_up_process(kapmd_tsk); - -#ifdef CONFIG_PROC_FS - create_proc_info_entry("apm", 0, NULL, apm_get_info); -#endif - - ret = misc_register(&apm_device); - if (ret != 0) { - remove_proc_entry("apm", NULL); - kthread_stop(kapmd_tsk); - } - - return ret; -} - -static void __exit apm_exit(void) -{ - misc_deregister(&apm_device); - remove_proc_entry("apm", NULL); - - kthread_stop(kapmd_tsk); -} - -module_init(apm_init); -module_exit(apm_exit); - -MODULE_AUTHOR("Stephen Rothwell"); -MODULE_DESCRIPTION("Advanced Power Management"); -MODULE_LICENSE("GPL"); - -#ifndef MODULE -static int __init apm_setup(char *str) -{ - while ((str != NULL) && (*str != '\0')) { - if (strncmp(str, "off", 3) == 0) - apm_disabled = 1; - if (strncmp(str, "on", 2) == 0) - apm_disabled = 0; - str = strchr(str, ','); - if (str != NULL) - str += strspn(str, ", \t"); - } - return 1; -} - -__setup("apm=", apm_setup); -#endif - -/** - * apm_queue_event - queue an APM event for kapmd - * @event: APM event - * - * Queue an APM event for kapmd to process and ultimately take the - * appropriate action. Only a subset of events are handled: - * %APM_LOW_BATTERY - * %APM_POWER_STATUS_CHANGE - * %APM_USER_SUSPEND - * %APM_SYS_SUSPEND - * %APM_CRITICAL_SUSPEND - */ -void apm_queue_event(apm_event_t event) -{ - unsigned long flags; - - spin_lock_irqsave(&kapmd_queue_lock, flags); - queue_add_event(&kapmd_queue, event); - spin_unlock_irqrestore(&kapmd_queue_lock, flags); - - wake_up_interruptible(&kapmd_wait); -} -EXPORT_SYMBOL(apm_queue_event); |
