sysfs.c

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/*
 * sysfs.c - ACPI sysfs interface to userspace.
 */

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/moduleparam.h>
#include <acpi/acpi_drivers.h>

#define _COMPONENT      ACPI_SYSTEM_COMPONENT
ACPI_MODULE_NAME("sysfs");

#define PREFIX "ACPI: "

#ifdef CONFIG_ACPI_DEBUG
/*
 * ACPI debug sysfs I/F, including:
 * /sys/modules/acpi/parameters/debug_layer
 * /sys/modules/acpi/parameters/debug_level
 * /sys/modules/acpi/parameters/trace_method_name
 * /sys/modules/acpi/parameters/trace_state
 * /sys/modules/acpi/parameters/trace_debug_layer
 * /sys/modules/acpi/parameters/trace_debug_level
 */

struct acpi_dlayer {
    const char *name;
    unsigned long value;
};
struct acpi_dlevel {
    const char *name;
    unsigned long value;
};
#define ACPI_DEBUG_INIT(v)  { .name = #v, .value = v }

static const struct acpi_dlayer acpi_debug_layers[] = {
    ACPI_DEBUG_INIT(ACPI_UTILITIES),
    ACPI_DEBUG_INIT(ACPI_HARDWARE),
    ACPI_DEBUG_INIT(ACPI_EVENTS),
    ACPI_DEBUG_INIT(ACPI_TABLES),
    ACPI_DEBUG_INIT(ACPI_NAMESPACE),
    ACPI_DEBUG_INIT(ACPI_PARSER),
    ACPI_DEBUG_INIT(ACPI_DISPATCHER),
    ACPI_DEBUG_INIT(ACPI_EXECUTER),
    ACPI_DEBUG_INIT(ACPI_RESOURCES),
    ACPI_DEBUG_INIT(ACPI_CA_DEBUGGER),
    ACPI_DEBUG_INIT(ACPI_OS_SERVICES),
    ACPI_DEBUG_INIT(ACPI_CA_DISASSEMBLER),
    ACPI_DEBUG_INIT(ACPI_COMPILER),
    ACPI_DEBUG_INIT(ACPI_TOOLS),

    ACPI_DEBUG_INIT(ACPI_BUS_COMPONENT),
    ACPI_DEBUG_INIT(ACPI_AC_COMPONENT),
    ACPI_DEBUG_INIT(ACPI_BATTERY_COMPONENT),
    ACPI_DEBUG_INIT(ACPI_BUTTON_COMPONENT),
    ACPI_DEBUG_INIT(ACPI_SBS_COMPONENT),
    ACPI_DEBUG_INIT(ACPI_FAN_COMPONENT),
    ACPI_DEBUG_INIT(ACPI_PCI_COMPONENT),
    ACPI_DEBUG_INIT(ACPI_POWER_COMPONENT),
    ACPI_DEBUG_INIT(ACPI_CONTAINER_COMPONENT),
    ACPI_DEBUG_INIT(ACPI_SYSTEM_COMPONENT),
    ACPI_DEBUG_INIT(ACPI_THERMAL_COMPONENT),
    ACPI_DEBUG_INIT(ACPI_MEMORY_DEVICE_COMPONENT),
    ACPI_DEBUG_INIT(ACPI_VIDEO_COMPONENT),
    ACPI_DEBUG_INIT(ACPI_PROCESSOR_COMPONENT),
};

static const struct acpi_dlevel acpi_debug_levels[] = {
    ACPI_DEBUG_INIT(ACPI_LV_INIT),
    ACPI_DEBUG_INIT(ACPI_LV_DEBUG_OBJECT),
    ACPI_DEBUG_INIT(ACPI_LV_INFO),

    ACPI_DEBUG_INIT(ACPI_LV_INIT_NAMES),
    ACPI_DEBUG_INIT(ACPI_LV_PARSE),
    ACPI_DEBUG_INIT(ACPI_LV_LOAD),
    ACPI_DEBUG_INIT(ACPI_LV_DISPATCH),
    ACPI_DEBUG_INIT(ACPI_LV_EXEC),
    ACPI_DEBUG_INIT(ACPI_LV_NAMES),
    ACPI_DEBUG_INIT(ACPI_LV_OPREGION),
    ACPI_DEBUG_INIT(ACPI_LV_BFIELD),
    ACPI_DEBUG_INIT(ACPI_LV_TABLES),
    ACPI_DEBUG_INIT(ACPI_LV_VALUES),
    ACPI_DEBUG_INIT(ACPI_LV_OBJECTS),
    ACPI_DEBUG_INIT(ACPI_LV_RESOURCES),
    ACPI_DEBUG_INIT(ACPI_LV_USER_REQUESTS),
    ACPI_DEBUG_INIT(ACPI_LV_PACKAGE),

    ACPI_DEBUG_INIT(ACPI_LV_ALLOCATIONS),
    ACPI_DEBUG_INIT(ACPI_LV_FUNCTIONS),
    ACPI_DEBUG_INIT(ACPI_LV_OPTIMIZATIONS),

    ACPI_DEBUG_INIT(ACPI_LV_MUTEX),
    ACPI_DEBUG_INIT(ACPI_LV_THREADS),
    ACPI_DEBUG_INIT(ACPI_LV_IO),
    ACPI_DEBUG_INIT(ACPI_LV_INTERRUPTS),

    ACPI_DEBUG_INIT(ACPI_LV_AML_DISASSEMBLE),
    ACPI_DEBUG_INIT(ACPI_LV_VERBOSE_INFO),
    ACPI_DEBUG_INIT(ACPI_LV_FULL_TABLES),
    ACPI_DEBUG_INIT(ACPI_LV_EVENTS),
};

static int param_get_debug_layer(char *buffer, const struct kernel_param *kp)
{
    int result = 0;
    int i;

    result = sprintf(buffer, "%-25s\tHex        SET\n", "Description");

    for (i = 0; i < ARRAY_SIZE(acpi_debug_layers); i++) {
        result += sprintf(buffer + result, "%-25s\t0x%08lX [%c]\n",
                  acpi_debug_layers[i].name,
                  acpi_debug_layers[i].value,
                  (acpi_dbg_layer & acpi_debug_layers[i].value)
                  ? '*' : ' ');
    }
    result +=
        sprintf(buffer + result, "%-25s\t0x%08X [%c]\n", "ACPI_ALL_DRIVERS",
            ACPI_ALL_DRIVERS,
            (acpi_dbg_layer & ACPI_ALL_DRIVERS) ==
            ACPI_ALL_DRIVERS ? '*' : (acpi_dbg_layer & ACPI_ALL_DRIVERS)
            == 0 ? ' ' : '-');
    result +=
        sprintf(buffer + result,
            "--\ndebug_layer = 0x%08X ( * = enabled)\n",
            acpi_dbg_layer);

    return result;
}

static int param_get_debug_level(char *buffer, const struct kernel_param *kp)
{
    int result = 0;
    int i;

    result = sprintf(buffer, "%-25s\tHex        SET\n", "Description");

    for (i = 0; i < ARRAY_SIZE(acpi_debug_levels); i++) {
        result += sprintf(buffer + result, "%-25s\t0x%08lX [%c]\n",
                  acpi_debug_levels[i].name,
                  acpi_debug_levels[i].value,
                  (acpi_dbg_level & acpi_debug_levels[i].value)
                  ? '*' : ' ');
    }
    result +=
        sprintf(buffer + result, "--\ndebug_level = 0x%08X (* = enabled)\n",
            acpi_dbg_level);

    return result;
}

static const struct kernel_param_ops param_ops_debug_layer = {
    .set = param_set_uint,
    .get = param_get_debug_layer,
};

static const struct kernel_param_ops param_ops_debug_level = {
    .set = param_set_uint,
    .get = param_get_debug_level,
};

module_param_cb(debug_layer, &param_ops_debug_layer, &acpi_dbg_layer, 0644);
module_param_cb(debug_level, &param_ops_debug_level, &acpi_dbg_level, 0644);

static char trace_method_name[6];
module_param_string(trace_method_name, trace_method_name, 6, 0644);
static unsigned int trace_debug_layer;
module_param(trace_debug_layer, uint, 0644);
static unsigned int trace_debug_level;
module_param(trace_debug_level, uint, 0644);

static int param_set_trace_state(const char *val, struct kernel_param *kp)
{
    int result = 0;

    if (!strncmp(val, "enable", sizeof("enable") - 1)) {
        result = acpi_debug_trace(trace_method_name, trace_debug_level,
                      trace_debug_layer, 0);
        if (result)
            result = -EBUSY;
        goto exit;
    }

    if (!strncmp(val, "disable", sizeof("disable") - 1)) {
        int name = 0;
        result = acpi_debug_trace((char *)&name, trace_debug_level,
                      trace_debug_layer, 0);
        if (result)
            result = -EBUSY;
        goto exit;
    }

    if (!strncmp(val, "1", 1)) {
        result = acpi_debug_trace(trace_method_name, trace_debug_level,
                      trace_debug_layer, 1);
        if (result)
            result = -EBUSY;
        goto exit;
    }

    result = -EINVAL;
exit:
    return result;
}

static int param_get_trace_state(char *buffer, struct kernel_param *kp)
{
    if (!acpi_gbl_trace_method_name)
        return sprintf(buffer, "disable");
    else {
        if (acpi_gbl_trace_flags & 1)
            return sprintf(buffer, "1");
        else
            return sprintf(buffer, "enable");
    }
    return 0;
}

module_param_call(trace_state, param_set_trace_state, param_get_trace_state,
          NULL, 0644);
#endif /* CONFIG_ACPI_DEBUG */


/* /sys/modules/acpi/parameters/aml_debug_output */

module_param_named(aml_debug_output, acpi_gbl_enable_aml_debug_object,
           bool, 0644);
MODULE_PARM_DESC(aml_debug_output,
         "To enable/disable the ACPI Debug Object output.");

/* /sys/module/acpi/parameters/acpica_version */
static int param_get_acpica_version(char *buffer, struct kernel_param *kp)
{
    int result;

    result = sprintf(buffer, "%x", ACPI_CA_VERSION);

    return result;
}

module_param_call(acpica_version, NULL, param_get_acpica_version, NULL, 0444);

/*
 * ACPI table sysfs I/F:
 * /sys/firmware/acpi/tables/
 * /sys/firmware/acpi/tables/dynamic/
 */

static LIST_HEAD(acpi_table_attr_list);
static struct kobject *tables_kobj;
static struct kobject *dynamic_tables_kobj;

struct acpi_table_attr {
    struct bin_attribute attr;
    char name[8];
    int instance;
    struct list_head node;
};

static ssize_t acpi_table_show(struct file *filp, struct kobject *kobj,
                   struct bin_attribute *bin_attr, char *buf,
                   loff_t offset, size_t count)
{
    struct acpi_table_attr *table_attr =
        container_of(bin_attr, struct acpi_table_attr, attr);
    struct acpi_table_header *table_header = NULL;
    acpi_status status;
    char name[ACPI_NAME_SIZE];

    if (strncmp(table_attr->name, "NULL", 4))
        memcpy(name, table_attr->name, ACPI_NAME_SIZE);
    else
        memcpy(name, "\0\0\0\0", 4);

    status = acpi_get_table(name, table_attr->instance, &table_header);
    if (ACPI_FAILURE(status))
        return -ENODEV;

    return memory_read_from_buffer(buf, count, &offset,
                       table_header, table_header->length);
}

static void acpi_table_attr_init(struct acpi_table_attr *table_attr,
                 struct acpi_table_header *table_header)
{
    struct acpi_table_header *header = NULL;
    struct acpi_table_attr *attr = NULL;

    sysfs_attr_init(&table_attr->attr.attr);
    if (table_header->signature[0] != '\0')
        memcpy(table_attr->name, table_header->signature,
               ACPI_NAME_SIZE);
    else
        memcpy(table_attr->name, "NULL", 4);

    list_for_each_entry(attr, &acpi_table_attr_list, node) {
        if (!memcmp(table_attr->name, attr->name, ACPI_NAME_SIZE))
            if (table_attr->instance < attr->instance)
                table_attr->instance = attr->instance;
    }
    table_attr->instance++;

    if (table_attr->instance > 1 || (table_attr->instance == 1 &&
                     !acpi_get_table
                     (table_header->signature, 2, &header)))
        sprintf(table_attr->name + ACPI_NAME_SIZE, "%d",
            table_attr->instance);

    table_attr->attr.size = 0;
    table_attr->attr.read = acpi_table_show;
    table_attr->attr.attr.name = table_attr->name;
    table_attr->attr.attr.mode = 0400;

    return;
}

static acpi_status
acpi_sysfs_table_handler(u32 event, void *table, void *context)
{
    struct acpi_table_attr *table_attr;

    switch (event) {
    case ACPI_TABLE_EVENT_LOAD:
        table_attr =
            kzalloc(sizeof(struct acpi_table_attr), GFP_KERNEL);
        if (!table_attr)
            return AE_NO_MEMORY;

        acpi_table_attr_init(table_attr, table);
        if (sysfs_create_bin_file(dynamic_tables_kobj,
                      &table_attr->attr)) {
            kfree(table_attr);
            return AE_ERROR;
        } else
            list_add_tail(&table_attr->node, &acpi_table_attr_list);
        break;
    case ACPI_TABLE_EVENT_UNLOAD:
        /*
         * we do not need to do anything right now
         * because the table is not deleted from the
         * global table list when unloading it.
         */
        break;
    default:
        return AE_BAD_PARAMETER;
    }
    return AE_OK;
}

static int acpi_tables_sysfs_init(void)
{
    struct acpi_table_attr *table_attr;
    struct acpi_table_header *table_header = NULL;
    int table_index = 0;
    int result;

    tables_kobj = kobject_create_and_add("tables", acpi_kobj);
    if (!tables_kobj)
        goto err;

    dynamic_tables_kobj = kobject_create_and_add("dynamic", tables_kobj);
    if (!dynamic_tables_kobj)
        goto err_dynamic_tables;

    do {
        result = acpi_get_table_by_index(table_index, &table_header);
        if (!result) {
            table_index++;
            table_attr = NULL;
            table_attr =
                kzalloc(sizeof(struct acpi_table_attr), GFP_KERNEL);
            if (!table_attr)
                return -ENOMEM;

            acpi_table_attr_init(table_attr, table_header);
            result =
                sysfs_create_bin_file(tables_kobj,
                          &table_attr->attr);
            if (result) {
                kfree(table_attr);
                return result;
            } else
                list_add_tail(&table_attr->node,
                          &acpi_table_attr_list);
        }
    } while (!result);
    kobject_uevent(tables_kobj, KOBJ_ADD);
    kobject_uevent(dynamic_tables_kobj, KOBJ_ADD);
    result = acpi_install_table_handler(acpi_sysfs_table_handler, NULL);

    return result == AE_OK ? 0 : -EINVAL;
err_dynamic_tables:
    kobject_put(tables_kobj);
err:
    return -ENOMEM;
}

/*
 * Detailed ACPI IRQ counters:
 * /sys/firmware/acpi/interrupts/
 */

u32 acpi_irq_handled;
u32 acpi_irq_not_handled;

#define COUNT_GPE 0
#define COUNT_SCI 1     /* acpi_irq_handled */
#define COUNT_SCI_NOT 2     /* acpi_irq_not_handled */
#define COUNT_ERROR 3       /* other */
#define NUM_COUNTERS_EXTRA 4

struct event_counter {
    u32 count;
    u32 flags;
};

static struct event_counter *all_counters;
static u32 num_gpes;
static u32 num_counters;
static struct attribute **all_attrs;
static u32 acpi_gpe_count;

static struct attribute_group interrupt_stats_attr_group = {
    .name = "interrupts",
};

static struct kobj_attribute *counter_attrs;

static void delete_gpe_attr_array(void)
{
    struct event_counter *tmp = all_counters;

    all_counters = NULL;
    kfree(tmp);

    if (counter_attrs) {
        int i;

        for (i = 0; i < num_gpes; i++)
            kfree(counter_attrs[i].attr.name);

        kfree(counter_attrs);
    }
    kfree(all_attrs);

    return;
}

static void gpe_count(u32 gpe_number)
{
    acpi_gpe_count++;

    if (!all_counters)
        return;

    if (gpe_number < num_gpes)
        all_counters[gpe_number].count++;
    else
        all_counters[num_gpes + ACPI_NUM_FIXED_EVENTS +
                 COUNT_ERROR].count++;

    return;
}

static void fixed_event_count(u32 event_number)
{
    if (!all_counters)
        return;

    if (event_number < ACPI_NUM_FIXED_EVENTS)
        all_counters[num_gpes + event_number].count++;
    else
        all_counters[num_gpes + ACPI_NUM_FIXED_EVENTS +
                 COUNT_ERROR].count++;

    return;
}

static void acpi_gbl_event_handler(u32 event_type, acpi_handle device,
    u32 event_number, void *context)
{
    if (event_type == ACPI_EVENT_TYPE_GPE)
        gpe_count(event_number);

    if (event_type == ACPI_EVENT_TYPE_FIXED)
        fixed_event_count(event_number);
}

static int get_status(u32 index, acpi_event_status *status,
              acpi_handle *handle)
{
    int result = 0;

    if (index >= num_gpes + ACPI_NUM_FIXED_EVENTS)
        goto end;

    if (index < num_gpes) {
        result = acpi_get_gpe_device(index, handle);
        if (result) {
            ACPI_EXCEPTION((AE_INFO, AE_NOT_FOUND,
                    "Invalid GPE 0x%x\n", index));
            goto end;
        }
        result = acpi_get_gpe_status(*handle, index, status);
    } else if (index < (num_gpes + ACPI_NUM_FIXED_EVENTS))
        result = acpi_get_event_status(index - num_gpes, status);

end:
    return result;
}

static ssize_t counter_show(struct kobject *kobj,
                struct kobj_attribute *attr, char *buf)
{
    int index = attr - counter_attrs;
    int size;
    acpi_handle handle;
    acpi_event_status status;
    int result = 0;

    all_counters[num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_SCI].count =
        acpi_irq_handled;
    all_counters[num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_SCI_NOT].count =
        acpi_irq_not_handled;
    all_counters[num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_GPE].count =
        acpi_gpe_count;
    size = sprintf(buf, "%8d", all_counters[index].count);

    /* "gpe_all" or "sci" */
    if (index >= num_gpes + ACPI_NUM_FIXED_EVENTS)
        goto end;

    result = get_status(index, &status, &handle);
    if (result)
        goto end;

    if (!(status & ACPI_EVENT_FLAG_HANDLE))
        size += sprintf(buf + size, "   invalid");
    else if (status & ACPI_EVENT_FLAG_ENABLED)
        size += sprintf(buf + size, "   enabled");
    else if (status & ACPI_EVENT_FLAG_WAKE_ENABLED)
        size += sprintf(buf + size, "   wake_enabled");
    else
        size += sprintf(buf + size, "   disabled");

end:
    size += sprintf(buf + size, "\n");
    return result ? result : size;
}

/*
 * counter_set() sets the specified counter.
 * setting the total "sci" file to any value clears all counters.
 * enable/disable/clear a gpe/fixed event in user space.
 */
static ssize_t counter_set(struct kobject *kobj,
               struct kobj_attribute *attr, const char *buf,
               size_t size)
{
    int index = attr - counter_attrs;
    acpi_event_status status;
    acpi_handle handle;
    int result = 0;

    if (index == num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_SCI) {
        int i;
        for (i = 0; i < num_counters; ++i)
            all_counters[i].count = 0;
        acpi_gpe_count = 0;
        acpi_irq_handled = 0;
        acpi_irq_not_handled = 0;
        goto end;
    }

    /* show the event status for both GPEs and Fixed Events */
    result = get_status(index, &status, &handle);
    if (result)
        goto end;

    if (!(status & ACPI_EVENT_FLAG_HANDLE)) {
        printk(KERN_WARNING PREFIX
               "Can not change Invalid GPE/Fixed Event status\n");
        return -EINVAL;
    }

    if (index < num_gpes) {
        if (!strcmp(buf, "disable\n") &&
            (status & ACPI_EVENT_FLAG_ENABLED))
            result = acpi_disable_gpe(handle, index);
        else if (!strcmp(buf, "enable\n") &&
             !(status & ACPI_EVENT_FLAG_ENABLED))
            result = acpi_enable_gpe(handle, index);
        else if (!strcmp(buf, "clear\n") &&
             (status & ACPI_EVENT_FLAG_SET))
            result = acpi_clear_gpe(handle, index);
        else
            all_counters[index].count = strtoul(buf, NULL, 0);
    } else if (index < num_gpes + ACPI_NUM_FIXED_EVENTS) {
        int event = index - num_gpes;
        if (!strcmp(buf, "disable\n") &&
            (status & ACPI_EVENT_FLAG_ENABLED))
            result = acpi_disable_event(event, ACPI_NOT_ISR);
        else if (!strcmp(buf, "enable\n") &&
             !(status & ACPI_EVENT_FLAG_ENABLED))
            result = acpi_enable_event(event, ACPI_NOT_ISR);
        else if (!strcmp(buf, "clear\n") &&
             (status & ACPI_EVENT_FLAG_SET))
            result = acpi_clear_event(event);
        else
            all_counters[index].count = strtoul(buf, NULL, 0);
    } else
        all_counters[index].count = strtoul(buf, NULL, 0);

    if (ACPI_FAILURE(result))
        result = -EINVAL;
end:
    return result ? result : size;
}

void acpi_irq_stats_init(void)
{
    acpi_status status;
    int i;

    if (all_counters)
        return;

    num_gpes = acpi_current_gpe_count;
    num_counters = num_gpes + ACPI_NUM_FIXED_EVENTS + NUM_COUNTERS_EXTRA;

    all_attrs = kzalloc(sizeof(struct attribute *) * (num_counters + 1),
                GFP_KERNEL);
    if (all_attrs == NULL)
        return;

    all_counters = kzalloc(sizeof(struct event_counter) * (num_counters),
                   GFP_KERNEL);
    if (all_counters == NULL)
        goto fail;

    status = acpi_install_global_event_handler(acpi_gbl_event_handler, NULL);
    if (ACPI_FAILURE(status))
        goto fail;

    counter_attrs = kzalloc(sizeof(struct kobj_attribute) * (num_counters),
                GFP_KERNEL);
    if (counter_attrs == NULL)
        goto fail;

    for (i = 0; i < num_counters; ++i) {
        char buffer[12];
        char *name;

        if (i < num_gpes)
            sprintf(buffer, "gpe%02X", i);
        else if (i == num_gpes + ACPI_EVENT_PMTIMER)
            sprintf(buffer, "ff_pmtimer");
        else if (i == num_gpes + ACPI_EVENT_GLOBAL)
            sprintf(buffer, "ff_gbl_lock");
        else if (i == num_gpes + ACPI_EVENT_POWER_BUTTON)
            sprintf(buffer, "ff_pwr_btn");
        else if (i == num_gpes + ACPI_EVENT_SLEEP_BUTTON)
            sprintf(buffer, "ff_slp_btn");
        else if (i == num_gpes + ACPI_EVENT_RTC)
            sprintf(buffer, "ff_rt_clk");
        else if (i == num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_GPE)
            sprintf(buffer, "gpe_all");
        else if (i == num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_SCI)
            sprintf(buffer, "sci");
        else if (i == num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_SCI_NOT)
            sprintf(buffer, "sci_not");
        else if (i == num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_ERROR)
            sprintf(buffer, "error");
        else
            sprintf(buffer, "bug%02X", i);

        name = kzalloc(strlen(buffer) + 1, GFP_KERNEL);
        if (name == NULL)
            goto fail;
        strncpy(name, buffer, strlen(buffer) + 1);

        sysfs_attr_init(&counter_attrs[i].attr);
        counter_attrs[i].attr.name = name;
        counter_attrs[i].attr.mode = 0644;
        counter_attrs[i].show = counter_show;
        counter_attrs[i].store = counter_set;

        all_attrs[i] = &counter_attrs[i].attr;
    }

    interrupt_stats_attr_group.attrs = all_attrs;
    if (!sysfs_create_group(acpi_kobj, &interrupt_stats_attr_group))
        return;

fail:
    delete_gpe_attr_array();
    return;
}

static void __exit interrupt_stats_exit(void)
{
    sysfs_remove_group(acpi_kobj, &interrupt_stats_attr_group);

    delete_gpe_attr_array();

    return;
}

static ssize_t
acpi_show_profile(struct device *dev, struct device_attribute *attr,
          char *buf)
{
    return sprintf(buf, "%d\n", acpi_gbl_FADT.preferred_profile);
}

static const struct device_attribute pm_profile_attr =
    __ATTR(pm_profile, S_IRUGO, acpi_show_profile, NULL);

int __init acpi_sysfs_init(void)
{
    int result;

    result = acpi_tables_sysfs_init();
    if (result)
        return result;
    result = sysfs_create_file(acpi_kobj, &pm_profile_attr.attr);
    return result;
}