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Commit b6ce4083 authored by Vladimir Lebedev's avatar Vladimir Lebedev Committed by Len Brown
Browse files

ACPI: Cache battery status instead of re-evaluating AML 



/proc exports _BST in a single file, and _BST is re-evaulated
whenever that file is read.

Sometimes user-space reads this file frequently, and on some
systems _BST takes a long time to evaluate due to a slow EC.

Further, when we move to sysfs, the values returned from _BST
will be in multiple files, and evaluating _BST for each
file read would make matters worse.

Here code is added to support caching the results of _BST.
A new module parameter "update_time" tells how many seconds the
cached _BST should be used before it is re-evaluated.
Currently, update_time defaults to 0, and so the
existing behaviour of re-evaluating on each read retained.

Signed-off-by: default avatarVladimir Lebedev <vladimir.p.lebedev@intel.com>
Signed-off-by: default avatarLen Brown <len.brown@intel.com>
parent a1f0eff2

drivers/acpi/battery.c

+441 −172
Original line number Diff line number Diff line
@@ -52,12 +52,24 @@ 
#define ACPI_BATTERY_UNITS_AMPS		"mA"



#define _COMPONENT		ACPI_BATTERY_COMPONENT



#define ACPI_BATTERY_UPDATE_TIME	0



#define ACPI_BATTERY_NONE_UPDATE	0

#define ACPI_BATTERY_EASY_UPDATE	1

#define ACPI_BATTERY_INIT_UPDATE	2



ACPI_MODULE_NAME("battery");



MODULE_AUTHOR("Paul Diefenbaugh");

MODULE_DESCRIPTION("ACPI Battery Driver");

MODULE_LICENSE("GPL");



static unsigned int update_time = ACPI_BATTERY_UPDATE_TIME;



/* 0 - every time, > 0 - by update_time */

module_param(update_time, uint, 0644);



extern struct proc_dir_entry *acpi_lock_battery_dir(void);

extern void *acpi_unlock_battery_dir(struct proc_dir_entry *acpi_battery_dir);
@@ -100,32 +112,117 @@ struct acpi_battery_info { 
};



struct acpi_battery_flags {

	u8 present:1;		/* Bay occupied? */

	u8 power_unit:1;	/* 0=watts, 1=apms */

	u8 alarm:1;		/* _BTP present? */

	u8 reserved:5;

};



struct acpi_battery_trips {

	unsigned long warning;

	unsigned long low;

	u8 battery_present_prev;

	u8 alarm_present;

	u8 init_update;

	u8 info_update;

	u8 state_update;

	u8 alarm_update;

	u8 power_unit;

};



struct acpi_battery {

	struct mutex mutex;

	struct acpi_device * device;

	struct acpi_battery_flags flags;

	struct acpi_battery_trips trips;

	struct acpi_buffer bif_data;

	struct acpi_buffer bst_data;

	unsigned long alarm;

	struct acpi_battery_info *info;

	unsigned long info_update_time;

	unsigned long state_update_time;

	unsigned long alarm_update_time;

};



#define acpi_battery_present(battery) battery->device->status.battery_present

#define acpi_battery_present_prev(battery) battery->flags.battery_present_prev

#define acpi_battery_alarm_present(battery) battery->flags.alarm_present

#define acpi_battery_init_update_flag(battery) battery->flags.init_update

#define acpi_battery_info_update_flag(battery) battery->flags.info_update

#define acpi_battery_state_update_flag(battery) battery->flags.state_update

#define acpi_battery_alarm_update_flag(battery) battery->flags.alarm_update

#define acpi_battery_power_units(battery) battery->flags.power_unit ? \

		ACPI_BATTERY_UNITS_AMPS : ACPI_BATTERY_UNITS_WATTS

#define acpi_battery_handle(battery) battery->device->handle

#define acpi_battery_inserted(battery) (!acpi_battery_present_prev(battery) & acpi_battery_present(battery))

#define acpi_battery_removed(battery) (acpi_battery_present_prev(battery) & !acpi_battery_present(battery))

#define acpi_battery_bid(battery) acpi_device_bid(battery->device)

#define acpi_battery_status_str(battery) acpi_battery_present(battery) ? "present" : "absent"



/* --------------------------------------------------------------------------

                               Battery Management

   -------------------------------------------------------------------------- */



static int

acpi_battery_get_info(struct acpi_battery *battery,

		      struct acpi_battery_info **bif)

static void acpi_battery_mutex_lock(struct acpi_battery *battery)

{

	mutex_lock(&battery->mutex);

}



static void acpi_battery_mutex_unlock(struct acpi_battery *battery)

{

	mutex_unlock(&battery->mutex);

}



static void acpi_battery_check_result(struct acpi_battery *battery, int result)

{

	if (!battery)

		return;



	if (result) {

		acpi_battery_init_update_flag(battery) = 1;

	}

}



static int acpi_battery_extract_package(struct acpi_battery *battery,

					union acpi_object *package,

					struct acpi_buffer *format,

					struct acpi_buffer *data,

					char *package_name)

{

	acpi_status status = AE_OK;

	struct acpi_buffer data_null = { 0, NULL };



	status = acpi_extract_package(package, format, &data_null);

	if (status != AE_BUFFER_OVERFLOW) {

		ACPI_EXCEPTION((AE_INFO, status, "Extracting size %s",

				package_name));

		return -ENODEV;

	}



	if (data_null.length != data->length) {

		if (data->pointer) {

			kfree(data->pointer);

		}

		data->pointer = kzalloc(data_null.length, GFP_KERNEL);

		if (!data->pointer) {

			ACPI_EXCEPTION((AE_INFO, AE_NO_MEMORY, "kzalloc()"));

			return -ENOMEM;

		}

		data->length = data_null.length;

	}



	status = acpi_extract_package(package, format, data);

	if (ACPI_FAILURE(status)) {

		ACPI_EXCEPTION((AE_INFO, status, "Extracting %s",

				package_name));

		return -ENODEV;

	}



	return 0;

}



static int acpi_battery_get_status(struct acpi_battery *battery)

{

	int result = 0;



	result = acpi_bus_get_status(battery->device);

	if (result) {

		ACPI_EXCEPTION((AE_INFO, AE_ERROR, "Evaluating _STA"));

		return -ENODEV;

	}

	return result;

}



static int acpi_battery_get_info(struct acpi_battery *battery)

{

	int result = 0;

	acpi_status status = 0;
@@ -133,16 +230,18 @@ acpi_battery_get_info(struct acpi_battery *battery, 
	struct acpi_buffer format = { sizeof(ACPI_BATTERY_FORMAT_BIF),

		ACPI_BATTERY_FORMAT_BIF

	};

	struct acpi_buffer data = { 0, NULL };

	union acpi_object *package = NULL;

	struct acpi_buffer *data = NULL;

	struct acpi_battery_info *bif = NULL;



	battery->info_update_time = get_seconds();



	if (!battery || !bif)

		return -EINVAL;

	if (!acpi_battery_present(battery))

		return 0;



	/* Evalute _BIF */



	status = acpi_evaluate_object(battery->device->handle, "_BIF", NULL, &buffer);

	status = acpi_evaluate_object(acpi_battery_handle(battery), "_BIF", NULL, &buffer);

	if (ACPI_FAILURE(status)) {

		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BIF"));

		return -ENODEV;
@@ -150,41 +249,29 @@ acpi_battery_get_info(struct acpi_battery *battery, 


	package = buffer.pointer;



	/* Extract Package Data */

	data = &battery->bif_data;



	status = acpi_extract_package(package, &format, &data);

	if (status != AE_BUFFER_OVERFLOW) {

		ACPI_EXCEPTION((AE_INFO, status, "Extracting _BIF"));

		result = -ENODEV;

		goto end;

	}



	data.pointer = kzalloc(data.length, GFP_KERNEL);

	if (!data.pointer) {

		result = -ENOMEM;

		goto end;

	}

	/* Extract Package Data */



	status = acpi_extract_package(package, &format, &data);

	if (ACPI_FAILURE(status)) {

		ACPI_EXCEPTION((AE_INFO, status, "Extracting _BIF"));

		kfree(data.pointer);

		result = -ENODEV;

	result = acpi_battery_extract_package(battery, package, &format, data, "_BIF");

	if (result)

		goto end;

	}



      end:



	if (buffer.pointer) {

		kfree(buffer.pointer);

	}



	if (!result)

		(*bif) = data.pointer;

	if (!result) {

		bif = data->pointer;

		battery->flags.power_unit = bif->power_unit;

	}



	return result;

}



static int

acpi_battery_get_state(struct acpi_battery *battery,

			struct acpi_battery_state **bst)

static int acpi_battery_get_state(struct acpi_battery *battery)

{

	int result = 0;

	acpi_status status = 0;
@@ -192,16 +279,17 @@ acpi_battery_get_state(struct acpi_battery *battery, 
	struct acpi_buffer format = { sizeof(ACPI_BATTERY_FORMAT_BST),

		ACPI_BATTERY_FORMAT_BST

	};

	struct acpi_buffer data = { 0, NULL };

	union acpi_object *package = NULL;

	struct acpi_buffer *data = NULL;



	battery->state_update_time = get_seconds();



	if (!battery || !bst)

		return -EINVAL;

	if (!acpi_battery_present(battery))

		return 0;



	/* Evalute _BST */



	status = acpi_evaluate_object(battery->device->handle, "_BST", NULL, &buffer);

	status = acpi_evaluate_object(acpi_battery_handle(battery), "_BST", NULL, &buffer);

	if (ACPI_FAILURE(status)) {

		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BST"));

		return -ENODEV;
@@ -209,55 +297,46 @@ acpi_battery_get_state(struct acpi_battery *battery, 


	package = buffer.pointer;



	data = &battery->bst_data;



	/* Extract Package Data */



	status = acpi_extract_package(package, &format, &data);

	if (status != AE_BUFFER_OVERFLOW) {

		ACPI_EXCEPTION((AE_INFO, status, "Extracting _BST"));

		result = -ENODEV;

	result = acpi_battery_extract_package(battery, package, &format, data, "_BST");

	if (result)

		goto end;

	}



	data.pointer = kzalloc(data.length, GFP_KERNEL);

	if (!data.pointer) {

		result = -ENOMEM;

		goto end;

      end:

	if (buffer.pointer) {

		kfree(buffer.pointer);

	}



	status = acpi_extract_package(package, &format, &data);

	if (ACPI_FAILURE(status)) {

		ACPI_EXCEPTION((AE_INFO, status, "Extracting _BST"));

		kfree(data.pointer);

		result = -ENODEV;

		goto end;

	return result;

}



      end:

	kfree(buffer.pointer);



	if (!result)

		(*bst) = data.pointer;

static int acpi_battery_get_alarm(struct acpi_battery *battery)

{

	battery->alarm_update_time = get_seconds();



	return result;

	return 0;

}



static int

acpi_battery_set_alarm(struct acpi_battery *battery, unsigned long alarm)

static int acpi_battery_set_alarm(struct acpi_battery *battery, unsigned long alarm)

{

	acpi_status status = 0;

	union acpi_object arg0 = { ACPI_TYPE_INTEGER };

	struct acpi_object_list arg_list = { 1, &arg0 };



	battery->alarm_update_time = get_seconds();



	if (!battery)

		return -EINVAL;

	if (!acpi_battery_present(battery))

		return -ENODEV;



	if (!battery->flags.alarm)

	if (!acpi_battery_alarm_present(battery))

		return -ENODEV;



	arg0.integer.value = alarm;



	status = acpi_evaluate_object(battery->device->handle, "_BTP", &arg_list, NULL);

	status = acpi_evaluate_object(acpi_battery_handle(battery), "_BTP", &arg_list, NULL);

	if (ACPI_FAILURE(status))

		return -ENODEV;
@@ -268,65 +347,110 @@ acpi_battery_set_alarm(struct acpi_battery *battery, unsigned long alarm) 
	return 0;

}



static int acpi_battery_check(struct acpi_battery *battery)

static int acpi_battery_init_alarm(struct acpi_battery *battery)

{

	int result = 0;

	acpi_status status = AE_OK;

	acpi_handle handle = NULL;

	struct acpi_device *device = NULL;

	struct acpi_battery_info *bif = NULL;

	struct acpi_battery_info *bif = battery->bif_data.pointer;

	unsigned long alarm = battery->alarm;



	/* See if alarms are supported, and if so, set default */



	if (!battery)

		return -EINVAL;

	status = acpi_get_handle(acpi_battery_handle(battery), "_BTP", &handle);

	if (ACPI_SUCCESS(status)) {

		acpi_battery_alarm_present(battery) = 1;

		if (!alarm && bif) {

			alarm = bif->design_capacity_warning;

		}

		result = acpi_battery_set_alarm(battery, alarm);

		if (result)

			goto end;

	} else {

		acpi_battery_alarm_present(battery) = 0;

	}



	device = battery->device;

      end:



	result = acpi_bus_get_status(device);

	if (result)

	return result;

}



	/* Insertion? */



	if (!battery->flags.present && device->status.battery_present) {

static int acpi_battery_init_update(struct acpi_battery *battery)

{

	int result = 0;



		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Battery inserted\n"));

	result = acpi_battery_get_status(battery);

	if (result)

		return result;



		/* Evalute _BIF to get certain static information */

	acpi_battery_present_prev(battery) = acpi_battery_present(battery);



		result = acpi_battery_get_info(battery, &bif);

	if (acpi_battery_present(battery)) {

		result = acpi_battery_get_info(battery);

		if (result)

			return result;

		result = acpi_battery_get_state(battery);

		if (result)

			return result;



		battery->flags.power_unit = bif->power_unit;

		battery->trips.warning = bif->design_capacity_warning;

		battery->trips.low = bif->design_capacity_low;

		kfree(bif);

		acpi_battery_init_alarm(battery);

	}



		/* See if alarms are supported, and if so, set default */

	return result;

}



		status = acpi_get_handle(battery->device->handle, "_BTP", &handle);

		if (ACPI_SUCCESS(status)) {

			battery->flags.alarm = 1;

			acpi_battery_set_alarm(battery, battery->trips.warning);

static int acpi_battery_update(struct acpi_battery *battery,

			   int update, int *update_result_ptr)

{

	int result = 0;

	int update_result = ACPI_BATTERY_NONE_UPDATE;



	if (!acpi_battery_present(battery)) {

		update = 1;

	}



	if (acpi_battery_init_update_flag(battery)) {

		result = acpi_battery_init_update(battery);

		if (result)

			goto end;;

		update_result = ACPI_BATTERY_INIT_UPDATE;

	} else if (update) {

		result = acpi_battery_get_status(battery);

		if (result)

			goto end;;

		if (acpi_battery_inserted(battery) || acpi_battery_removed(battery)) {

			result = acpi_battery_init_update(battery);

			if (result)

				goto end;;

			update_result = ACPI_BATTERY_INIT_UPDATE;

		} else {

			update_result = ACPI_BATTERY_EASY_UPDATE;

		}

	}



	/* Removal? */

      end:



	else if (battery->flags.present && !device->status.battery_present) {

		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Battery removed\n"));

	}

	acpi_battery_init_update_flag(battery) = (result != 0);



	battery->flags.present = device->status.battery_present;

	*update_result_ptr = update_result;



	return result;

}



static void acpi_battery_check_present(struct acpi_battery *battery)

static void acpi_battery_notify_update(struct acpi_battery *battery)

{

	if (!battery->flags.present) {

		acpi_battery_check(battery);

	acpi_battery_get_status(battery);



	if (acpi_battery_init_update_flag(battery)) {

		return;

	}



	if (acpi_battery_inserted(battery) || acpi_battery_removed(battery)) {

		acpi_battery_init_update_flag(battery) = 1;

	} else {

		acpi_battery_info_update_flag(battery) = 1;

		acpi_battery_state_update_flag(battery) = 1;

		acpi_battery_alarm_update_flag(battery) = 1;

	}

}
@@ -335,37 +459,33 @@ static void acpi_battery_check_present(struct acpi_battery *battery) 
   -------------------------------------------------------------------------- */



static struct proc_dir_entry *acpi_battery_dir;

static int acpi_battery_read_info(struct seq_file *seq, void *offset)



static int acpi_battery_read_info_print(struct seq_file *seq, int result)

{

	int result = 0;

	struct acpi_battery *battery = seq->private;

	struct acpi_battery_info *bif = NULL;

	char *units = "?";





	if (!battery)

	if (result)

		goto end;



	acpi_battery_check_present(battery);



	if (battery->flags.present)

	if (acpi_battery_present(battery))

		seq_printf(seq, "present:                 yes\n");

	else {

		seq_printf(seq, "present:                 no\n");

		goto end;

	}



	/* Battery Info (_BIF) */



	result = acpi_battery_get_info(battery, &bif);

	if (result || !bif) {

		seq_printf(seq, "ERROR: Unable to read battery information\n");

	bif = battery->bif_data.pointer;

	if (!bif) {

		ACPI_EXCEPTION((AE_INFO, AE_ERROR, "BIF buffer is NULL"));

		result = -ENODEV;

		goto end;

	}



	units =

	    bif->

	    power_unit ? ACPI_BATTERY_UNITS_AMPS : ACPI_BATTERY_UNITS_WATTS;

	/* Battery Units */



	units = acpi_battery_power_units(battery);



	if (bif->design_capacity == ACPI_BATTERY_VALUE_UNKNOWN)

		seq_printf(seq, "design capacity:         unknown\n");
@@ -396,7 +516,6 @@ static int acpi_battery_read_info(struct seq_file *seq, void *offset) 
	else

		seq_printf(seq, "design voltage:          %d mV\n",

			   (u32) bif->design_voltage);



	seq_printf(seq, "design capacity warning: %d %sh\n",

		   (u32) bif->design_capacity_warning, units);

	seq_printf(seq, "design capacity low:     %d %sh\n",
@@ -411,9 +530,48 @@ static int acpi_battery_read_info(struct seq_file *seq, void *offset) 
	seq_printf(seq, "OEM info:                %s\n", bif->oem_info);



      end:

	kfree(bif);



	return 0;

	if (result)

		seq_printf(seq, "ERROR: Unable to read battery info\n");



	return result;

}



static int acpi_battery_read_info(struct seq_file *seq, void *offset)

{

	struct acpi_battery *battery = seq->private;

	int result = 0;

	int update_result = ACPI_BATTERY_NONE_UPDATE;

	int update = 0;



	acpi_battery_mutex_lock(battery);



	update = (get_seconds() - battery->info_update_time >= update_time);

	update = (update | acpi_battery_info_update_flag(battery));



	result = acpi_battery_update(battery, update, &update_result);

	if (result)

		goto end;



	/* Battery Info (_BIF) */



	if (update_result == ACPI_BATTERY_EASY_UPDATE) {

		result = acpi_battery_get_info(battery);

		if (result)

			goto end;

	}



      end:



	result = acpi_battery_read_info_print(seq, result);



	acpi_battery_check_result(battery, result);



	acpi_battery_info_update_flag(battery) = result;



	acpi_battery_mutex_unlock(battery);



	return result;

}



static int acpi_battery_info_open_fs(struct inode *inode, struct file *file)
@@ -421,40 +579,33 @@ static int acpi_battery_info_open_fs(struct inode *inode, struct file *file) 
	return single_open(file, acpi_battery_read_info, PDE(inode)->data);

}



static int acpi_battery_read_state(struct seq_file *seq, void *offset)

static int acpi_battery_read_state_print(struct seq_file *seq, int result)

{

	int result = 0;

	struct acpi_battery *battery = seq->private;

	struct acpi_battery_state *bst = NULL;

	char *units = "?";





	if (!battery)

	if (result)

		goto end;



	acpi_battery_check_present(battery);



	if (battery->flags.present)

	if (acpi_battery_present(battery))

		seq_printf(seq, "present:                 yes\n");

	else {

		seq_printf(seq, "present:                 no\n");

		goto end;

	}



	/* Battery Units */



	units =

	    battery->flags.

	    power_unit ? ACPI_BATTERY_UNITS_AMPS : ACPI_BATTERY_UNITS_WATTS;



	/* Battery Status (_BST) */



	result = acpi_battery_get_state(battery, &bst);

	if (result || !bst) {

		seq_printf(seq, "ERROR: Unable to read battery state\n");

	bst = battery->bst_data.pointer;

	if (!bst) {

		ACPI_EXCEPTION((AE_INFO, AE_ERROR, "BST buffer is NULL"));

		result = -ENODEV;

		goto end;

	}



	/* Battery Units */



	units = acpi_battery_power_units(battery);



	if (!(bst->state & 0x04))

		seq_printf(seq, "capacity state:          ok\n");

	else
@@ -490,9 +641,49 @@ static int acpi_battery_read_state(struct seq_file *seq, void *offset) 
			   (u32) bst->present_voltage);



      end:

	kfree(bst);



	return 0;

	if (result) {

		seq_printf(seq, "ERROR: Unable to read battery state\n");

	}



	return result;

}



static int acpi_battery_read_state(struct seq_file *seq, void *offset)

{

	struct acpi_battery *battery = seq->private;

	int result = 0;

	int update_result = ACPI_BATTERY_NONE_UPDATE;

	int update = 0;



	acpi_battery_mutex_lock(battery);



	update = (get_seconds() - battery->state_update_time >= update_time);

	update = (update | acpi_battery_state_update_flag(battery));



	result = acpi_battery_update(battery, update, &update_result);

	if (result)

		goto end;



	/* Battery State (_BST) */



	if (update_result == ACPI_BATTERY_EASY_UPDATE) {

		result = acpi_battery_get_state(battery);

		if (result)

			goto end;

	}



      end:



	result = acpi_battery_read_state_print(seq, result);



	acpi_battery_check_result(battery, result);



	acpi_battery_state_update_flag(battery) = result;



	acpi_battery_mutex_unlock(battery);



	return result;

}



static int acpi_battery_state_open_fs(struct inode *inode, struct file *file)
@@ -500,38 +691,72 @@ static int acpi_battery_state_open_fs(struct inode *inode, struct file *file) 
	return single_open(file, acpi_battery_read_state, PDE(inode)->data);

}



static int acpi_battery_read_alarm(struct seq_file *seq, void *offset)

static int acpi_battery_read_alarm_print(struct seq_file *seq, int result)

{

	struct acpi_battery *battery = seq->private;

	char *units = "?";





	if (!battery)

	if (result)

		goto end;



	acpi_battery_check_present(battery);



	if (!battery->flags.present) {

	if (!acpi_battery_present(battery)) {

		seq_printf(seq, "present:                 no\n");

		goto end;

	}



	/* Battery Units */



	units =

	    battery->flags.

	    power_unit ? ACPI_BATTERY_UNITS_AMPS : ACPI_BATTERY_UNITS_WATTS;



	/* Battery Alarm */

	units = acpi_battery_power_units(battery);



	seq_printf(seq, "alarm:                   ");

	if (!battery->alarm)

		seq_printf(seq, "unsupported\n");

	else

		seq_printf(seq, "%d %sh\n", (u32) battery->alarm, units);

		seq_printf(seq, "%lu %sh\n", battery->alarm, units);



      end:

	return 0;



	if (result)

		seq_printf(seq, "ERROR: Unable to read battery alarm\n");



	return result;

}



static int acpi_battery_read_alarm(struct seq_file *seq, void *offset)

{

	struct acpi_battery *battery = seq->private;

	int result = 0;

	int update_result = ACPI_BATTERY_NONE_UPDATE;

	int update = 0;



	acpi_battery_mutex_lock(battery);



	update = (get_seconds() - battery->alarm_update_time >= update_time);

	update = (update | acpi_battery_alarm_update_flag(battery));



	result = acpi_battery_update(battery, update, &update_result);

	if (result)

		goto end;



	/* Battery Alarm */



	if (update_result == ACPI_BATTERY_EASY_UPDATE) {

		result = acpi_battery_get_alarm(battery);

		if (result)

			goto end;

	}



      end:



	result = acpi_battery_read_alarm_print(seq, result);



	acpi_battery_check_result(battery, result);



	acpi_battery_alarm_update_flag(battery) = result;



	acpi_battery_mutex_unlock(battery);



	return result;

}



static ssize_t
@@ -543,27 +768,47 @@ acpi_battery_write_alarm(struct file *file, 
	char alarm_string[12] = { '\0' };

	struct seq_file *m = file->private_data;

	struct acpi_battery *battery = m->private;

	int update_result = ACPI_BATTERY_NONE_UPDATE;





	if (!battery || (count > sizeof(alarm_string) - 1))

		return -EINVAL;



	acpi_battery_check_present(battery);

	acpi_battery_mutex_lock(battery);



	if (!battery->flags.present)

		return -ENODEV;

	result = acpi_battery_update(battery, 1, &update_result);

	if (result) {

		result = -ENODEV;

		goto end;

	}



	if (!acpi_battery_present(battery)) {

		result = -ENODEV;

		goto end;

	}



	if (copy_from_user(alarm_string, buffer, count))

		return -EFAULT;

	if (copy_from_user(alarm_string, buffer, count)) {

		result = -EFAULT;

		goto end;

	}



	alarm_string[count] = '\0';



	result = acpi_battery_set_alarm(battery,

					simple_strtoul(alarm_string, NULL, 0));

	if (result)

		return result;

		goto end;



      end:



	acpi_battery_check_result(battery, result);



	return count;

	if (!result)

		result = count;



	acpi_battery_mutex_unlock(battery);



	return result;

}



static int acpi_battery_alarm_open_fs(struct inode *inode, struct file *file)
@@ -648,7 +893,6 @@ static int acpi_battery_add_fs(struct acpi_device *device) 


static int acpi_battery_remove_fs(struct acpi_device *device)

{



	if (acpi_device_dir(device)) {

		remove_proc_entry(ACPI_BATTERY_FILE_ALARM,

				  acpi_device_dir(device));
@@ -684,8 +928,11 @@ static void acpi_battery_notify(acpi_handle handle, u32 event, void *data) 
	case ACPI_BATTERY_NOTIFY_INFO:

	case ACPI_NOTIFY_BUS_CHECK:

	case ACPI_NOTIFY_DEVICE_CHECK:

		acpi_battery_check(battery);

		acpi_bus_generate_event(device, event, battery->flags.present);

		acpi_battery_mutex_lock(battery);

		device = battery->device;

		acpi_battery_notify_update(battery);

		acpi_battery_mutex_unlock(battery);

		acpi_bus_generate_event(device, event, acpi_battery_present(battery));

		break;

	default:

		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
@@ -702,7 +949,6 @@ static int acpi_battery_add(struct acpi_device *device) 
	acpi_status status = 0;

	struct acpi_battery *battery = NULL;





	if (!device)

		return -EINVAL;
@@ -710,15 +956,21 @@ static int acpi_battery_add(struct acpi_device *device) 
	if (!battery)

		return -ENOMEM;



	mutex_init(&battery->mutex);



	acpi_battery_mutex_lock(battery);



	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;



	result = acpi_battery_check(battery);

	result = acpi_battery_get_status(battery);

	if (result)

		goto end;



	acpi_battery_init_update_flag(battery) = 1;



	result = acpi_battery_add_fs(device);

	if (result)

		goto end;
@@ -727,6 +979,7 @@ static int acpi_battery_add(struct acpi_device *device) 
					     ACPI_ALL_NOTIFY,

					     acpi_battery_notify, battery);

	if (ACPI_FAILURE(status)) {

		ACPI_EXCEPTION((AE_INFO, status, "Installing notify handler"));

		result = -ENODEV;

		goto end;

	}
@@ -736,11 +989,14 @@ static int acpi_battery_add(struct acpi_device *device) 
	       device->status.battery_present ? "present" : "absent");



      end:



	if (result) {

		acpi_battery_remove_fs(device);

		kfree(battery);

	}



	acpi_battery_mutex_unlock(battery);



	return result;

}
@@ -749,18 +1005,29 @@ 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);



	acpi_battery_mutex_lock(battery);



	status = acpi_remove_notify_handler(device->handle,

					    ACPI_ALL_NOTIFY,

					    acpi_battery_notify);



	acpi_battery_remove_fs(device);



	if (battery->bif_data.pointer)

		kfree(battery->bif_data.pointer);



	if (battery->bst_data.pointer)

		kfree(battery->bst_data.pointer);



	acpi_battery_mutex_unlock(battery);



	mutex_destroy(&battery->mutex);



	kfree(battery);



	return 0;
@@ -775,7 +1042,10 @@ static int acpi_battery_resume(struct acpi_device *device) 
		return -EINVAL;



	battery = device->driver_data;

	return acpi_battery_check(battery);



	acpi_battery_init_update_flag(battery) = 1;



	return 0;

}



static int __init acpi_battery_init(void)
@@ -800,7 +1070,6 @@ static int __init acpi_battery_init(void) 


static void __exit acpi_battery_exit(void)

{



	acpi_bus_unregister_driver(&acpi_battery_driver);



	acpi_unlock_battery_dir(acpi_battery_dir);