battery.c

linux 内核源代码

		return result;
	return device_create_file(battery->bat.dev, &alarm_attr);
}

static void sysfs_remove_battery(struct acpi_battery *battery)
{
	if (!battery->bat.dev)
		return;
	device_remove_file(battery->bat.dev, &alarm_attr);
	power_supply_unregister(&battery->bat);
	battery->bat.dev = NULL;
}
#endif

static int acpi_battery_update(struct acpi_battery *battery)
{
	int result;
	result = acpi_battery_get_status(battery);
	if (result)
		return result;
#ifdef CONFIG_ACPI_SYSFS_POWER
	if (!acpi_battery_present(battery)) {
		sysfs_remove_battery(battery);
		battery->update_time = 0;
		return 0;
	}
#endif
	if (!battery->update_time) {
		result = acpi_battery_get_info(battery);
		if (result)
			return result;
		acpi_battery_init_alarm(battery);
	}
#ifdef CONFIG_ACPI_SYSFS_POWER
	if (!battery->bat.dev)
		sysfs_add_battery(battery);
#endif
	return acpi_battery_get_state(battery);
}

/* --------------------------------------------------------------------------
                              FS Interface (/proc)
   -------------------------------------------------------------------------- */

#ifdef CONFIG_ACPI_PROCFS_POWER
static struct proc_dir_entry *acpi_battery_dir;

static int acpi_battery_print_info(struct seq_file *seq, int result)
{
	struct acpi_battery *battery = seq->private;

	if (result)
		goto end;

	seq_printf(seq, "present:                 %s\n",
		   acpi_battery_present(battery)?"yes":"no");
	if (!acpi_battery_present(battery))
		goto end;
	if (battery->design_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
		seq_printf(seq, "design capacity:         unknown\n");
	else
		seq_printf(seq, "design capacity:         %d %sh\n",
			   battery->design_capacity,
			   acpi_battery_units(battery));

	if (battery->full_charge_capacity == ACPI_BATTERY_VALUE_UNKNOWN)
		seq_printf(seq, "last full capacity:      unknown\n");
	else
		seq_printf(seq, "last full capacity:      %d %sh\n",
			   battery->full_charge_capacity,
			   acpi_battery_units(battery));

	seq_printf(seq, "battery technology:      %srechargeable\n",
		   (!battery->technology)?"non-":"");

	if (battery->design_voltage == ACPI_BATTERY_VALUE_UNKNOWN)
		seq_printf(seq, "design voltage:          unknown\n");
	else
		seq_printf(seq, "design voltage:          %d mV\n",
			   battery->design_voltage);
	seq_printf(seq, "design capacity warning: %d %sh\n",
		   battery->design_capacity_warning,
		   acpi_battery_units(battery));
	seq_printf(seq, "design capacity low:     %d %sh\n",
		   battery->design_capacity_low,
		   acpi_battery_units(battery));
	seq_printf(seq, "capacity granularity 1:  %d %sh\n",
		   battery->capacity_granularity_1,
		   acpi_battery_units(battery));
	seq_printf(seq, "capacity granularity 2:  %d %sh\n",
		   battery->capacity_granularity_2,
		   acpi_battery_units(battery));
	seq_printf(seq, "model number:            %s\n", battery->model_number);
	seq_printf(seq, "serial number:           %s\n", battery->serial_number);
	seq_printf(seq, "battery type:            %s\n", battery->type);
	seq_printf(seq, "OEM info:                %s\n", battery->oem_info);
      end:
	if (result)
		seq_printf(seq, "ERROR: Unable to read battery info\n");
	return result;
}

static int acpi_battery_print_state(struct seq_file *seq, int result)
{
	struct acpi_battery *battery = seq->private;

	if (result)
		goto end;

	seq_printf(seq, "present:                 %s\n",
		   acpi_battery_present(battery)?"yes":"no");
	if (!acpi_battery_present(battery))
		goto end;

	seq_printf(seq, "capacity state:          %s\n",
			(battery->state & 0x04)?"critical":"ok");
	if ((battery->state & 0x01) && (battery->state & 0x02))
		seq_printf(seq,
			   "charging state:          charging/discharging\n");
	else if (battery->state & 0x01)
		seq_printf(seq, "charging state:          discharging\n");
	else if (battery->state & 0x02)
		seq_printf(seq, "charging state:          charging\n");
	else
		seq_printf(seq, "charging state:          charged\n");

	if (battery->current_now == ACPI_BATTERY_VALUE_UNKNOWN)
		seq_printf(seq, "present rate:            unknown\n");
	else
		seq_printf(seq, "present rate:            %d %s\n",
			   battery->current_now, acpi_battery_units(battery));

	if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN)
		seq_printf(seq, "remaining capacity:      unknown\n");
	else
		seq_printf(seq, "remaining capacity:      %d %sh\n",
			   battery->capacity_now, acpi_battery_units(battery));
	if (battery->voltage_now == ACPI_BATTERY_VALUE_UNKNOWN)
		seq_printf(seq, "present voltage:         unknown\n");
	else
		seq_printf(seq, "present voltage:         %d mV\n",
			   battery->voltage_now);
      end:
	if (result)
		seq_printf(seq, "ERROR: Unable to read battery state\n");

	return result;
}

static int acpi_battery_print_alarm(struct seq_file *seq, int result)
{
	struct acpi_battery *battery = seq->private;

	if (result)
		goto end;

	if (!acpi_battery_present(battery)) {
		seq_printf(seq, "present:                 no\n");
		goto end;
	}
	seq_printf(seq, "alarm:                   ");
	if (!battery->alarm)
		seq_printf(seq, "unsupported\n");
	else
		seq_printf(seq, "%u %sh\n", battery->alarm,
				acpi_battery_units(battery));
      end:
	if (result)
		seq_printf(seq, "ERROR: Unable to read battery alarm\n");
	return result;
}

static ssize_t acpi_battery_write_alarm(struct file *file,
					const char __user * buffer,
					size_t count, loff_t * ppos)
{
	int result = 0;
	char alarm_string[12] = { '\0' };
	struct seq_file *m = file->private_data;
	struct acpi_battery *battery = m->private;

	if (!battery || (count > sizeof(alarm_string) - 1))
		return -EINVAL;
	if (!acpi_battery_present(battery)) {
		result = -ENODEV;
		goto end;
	}
	if (copy_from_user(alarm_string, buffer, count)) {
		result = -EFAULT;
		goto end;
	}
	alarm_string[count] = '\0';
	battery->alarm = simple_strtol(alarm_string, NULL, 0);
	result = acpi_battery_set_alarm(battery);
      end:
	if (!result)
		return count;
	return result;
}

typedef int(*print_func)(struct seq_file *seq, int result);

static print_func acpi_print_funcs[ACPI_BATTERY_NUMFILES] = {
	acpi_battery_print_info,
	acpi_battery_print_state,
	acpi_battery_print_alarm,
};

static int acpi_battery_read(int fid, struct seq_file *seq)
{
	struct acpi_battery *battery = seq->private;
	int result = acpi_battery_update(battery);
	return acpi_print_funcs[fid](seq, result);
}

#define DECLARE_FILE_FUNCTIONS(_name) \
static int acpi_battery_read_##_name(struct seq_file *seq, void *offset) \
{ \
	return acpi_battery_read(_name##_tag, seq); \
} \
static int acpi_battery_##_name##_open_fs(struct inode *inode, struct file *file) \
{ \
	return single_open(file, acpi_battery_read_##_name, PDE(inode)->data); \
}

DECLARE_FILE_FUNCTIONS(info);
DECLARE_FILE_FUNCTIONS(state);
DECLARE_FILE_FUNCTIONS(alarm);

#undef DECLARE_FILE_FUNCTIONS

#define FILE_DESCRIPTION_RO(_name) \
	{ \
	.name = __stringify(_name), \
	.mode = S_IRUGO, \
	.ops = { \
		.open = acpi_battery_##_name##_open_fs, \
		.read = seq_read, \
		.llseek = seq_lseek, \
		.release = single_release, \
		.owner = THIS_MODULE, \
		}, \
	}

#define FILE_DESCRIPTION_RW(_name) \
	{ \
	.name = __stringify(_name), \
	.mode = S_IFREG | S_IRUGO | S_IWUSR, \
	.ops = { \
		.open = acpi_battery_##_name##_open_fs, \
		.read = seq_read, \
		.llseek = seq_lseek, \
		.write = acpi_battery_write_##_name, \
		.release = single_release, \
		.owner = THIS_MODULE, \
		}, \
	}

static struct battery_file {
	struct file_operations ops;
	mode_t mode;
	char *name;
} acpi_battery_file[] = {
	FILE_DESCRIPTION_RO(info),
	FILE_DESCRIPTION_RO(state),
	FILE_DESCRIPTION_RW(alarm),
};

#undef FILE_DESCRIPTION_RO
#undef FILE_DESCRIPTION_RW

static int acpi_battery_add_fs(struct acpi_device *device)
{
	struct proc_dir_entry *entry = NULL;
	int i;

	if (!acpi_device_dir(device)) {
		acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
						     acpi_battery_dir);
		if (!acpi_device_dir(device))
			return -ENODEV;
		acpi_device_dir(device)->owner = THIS_MODULE;
	}

	for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i) {
		entry = create_proc_entry(acpi_battery_file[i].name,
				  acpi_battery_file[i].mode, acpi_device_dir(device));
		if (!entry)
			return -ENODEV;
		else {
			entry->proc_fops = &acpi_battery_file[i].ops;
			entry->data = acpi_driver_data(device);
			entry->owner = THIS_MODULE;
		}
	}
	return 0;
}

static void acpi_battery_remove_fs(struct acpi_device *device)
{
	int i;
	if (!acpi_device_dir(device))
		return;
	for (i = 0; i < ACPI_BATTERY_NUMFILES; ++i)
		remove_proc_entry(acpi_battery_file[i].name,
				  acpi_device_dir(device));

	remove_proc_entry(acpi_device_bid(device), acpi_battery_dir);
	acpi_device_dir(device) = NULL;
}

#endif

/* --------------------------------------------------------------------------
                                 Driver Interface
   -------------------------------------------------------------------------- */

static void acpi_battery_notify(acpi_handle handle, u32 event, void *data)
{
	struct acpi_battery *battery = data;
	struct acpi_device *device;
	if (!battery)
		return;
	device = battery->device;
	acpi_battery_update(battery);
	acpi_bus_generate_proc_event(device, event,
				     acpi_battery_present(battery));
	acpi_bus_generate_netlink_event(device->pnp.device_class,
					device->dev.bus_id, event,
					acpi_battery_present(battery));
#ifdef CONFIG_ACPI_SYSFS_POWER
	/* acpi_batter_update could remove power_supply object */
	if (battery->bat.dev)
		kobject_uevent(&battery->bat.dev->kobj, KOBJ_CHANGE);
#endif
}

static int acpi_battery_add(struct acpi_device *device)
{
	int result = 0;
	acpi_status status = 0;
	struct acpi_battery *battery = NULL;
	if (!device)
		return -EINVAL;
	battery = kzalloc(sizeof(struct acpi_battery), GFP_KERNEL);
	if (!battery)
		return -ENOMEM;
	battery->device = device;
	strcpy(acpi_device_name(device), ACPI_BATTERY_DEVICE_NAME);
	strcpy(acpi_device_class(device), ACPI_BATTERY_CLASS);
	acpi_driver_data(device) = battery;
	mutex_init(&battery->lock);
	acpi_battery_update(battery);
#ifdef CONFIG_ACPI_PROCFS_POWER
	result = acpi_battery_add_fs(device);
	if (result)
		goto end;
#endif
	status = acpi_install_notify_handler(device->handle,
					     ACPI_ALL_NOTIFY,
					     acpi_battery_notify, battery);
	if (ACPI_FAILURE(status)) {
		ACPI_EXCEPTION((AE_INFO, status, "Installing notify handler"));
		result = -ENODEV;
		goto end;
	}
	printk(KERN_INFO PREFIX "%s Slot [%s] (battery %s)\n",
	       ACPI_BATTERY_DEVICE_NAME, acpi_device_bid(device),
	       device->status.battery_present ? "present" : "absent");
      end:
	if (result) {
#ifdef CONFIG_ACPI_PROCFS_POWER
		acpi_battery_remove_fs(device);
#endif
		kfree(battery);
	}
	return result;
}

static int acpi_battery_remove(struct acpi_device *device, int type)
{
	acpi_status status = 0;
	struct acpi_battery *battery = NULL;

	if (!device || !acpi_driver_data(device))
		return -EINVAL;
	battery = acpi_driver_data(device);
	status = acpi_remove_notify_handler(device->handle,
					    ACPI_ALL_NOTIFY,
					    acpi_battery_notify);
#ifdef CONFIG_ACPI_PROCFS_POWER
	acpi_battery_remove_fs(device);
#endif
#ifdef CONFIG_ACPI_SYSFS_POWER
	sysfs_remove_battery(battery);
#endif
	mutex_destroy(&battery->lock);
	kfree(battery);
	return 0;
}

/* this is needed to learn about changes made in suspended state */
static int acpi_battery_resume(struct acpi_device *device)
{
	struct acpi_battery *battery;
	if (!device)
		return -EINVAL;
	battery = acpi_driver_data(device);
	battery->update_time = 0;
	acpi_battery_update(battery);
	return 0;
}

static struct acpi_driver acpi_battery_driver = {
	.name = "battery",
	.class = ACPI_BATTERY_CLASS,
	.ids = battery_device_ids,
	.ops = {
		.add = acpi_battery_add,
		.resume = acpi_battery_resume,
		.remove = acpi_battery_remove,
		},
};

static int __init acpi_battery_init(void)
{
	if (acpi_disabled)
		return -ENODEV;
#ifdef CONFIG_ACPI_PROCFS_POWER
	acpi_battery_dir = acpi_lock_battery_dir();
	if (!acpi_battery_dir)
		return -ENODEV;
#endif
	if (acpi_bus_register_driver(&acpi_battery_driver) < 0) {
#ifdef CONFIG_ACPI_PROCFS_POWER
		acpi_unlock_battery_dir(acpi_battery_dir);
#endif
		return -ENODEV;
	}
	return 0;
}

static void __exit acpi_battery_exit(void)
{
	acpi_bus_unregister_driver(&acpi_battery_driver);
#ifdef CONFIG_ACPI_PROCFS_POWER
	acpi_unlock_battery_dir(acpi_battery_dir);
#endif
}

module_init(acpi_battery_init);
module_exit(acpi_battery_exit);