utids.c

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/******************************************************************************
 *
 * Module Name: utids - support for device Ids - HID, UID, CID
 *
 *****************************************************************************/

/*
 * Copyright (C) 2000 - 2012, Intel Corp.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification.
 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 *    substantially similar to the "NO WARRANTY" disclaimer below
 *    ("Disclaimer") and any redistribution must be conditioned upon
 *    including a substantially similar Disclaimer requirement for further
 *    binary redistribution.
 * 3. Neither the names of the above-listed copyright holders nor the names
 *    of any contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * Alternatively, this software may be distributed under the terms of the
 * GNU General Public License ("GPL") version 2 as published by the Free
 * Software Foundation.
 *
 * NO WARRANTY
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGES.
 */

#include <acpi/acpi.h>
#include "accommon.h"
#include "acinterp.h"

#define _COMPONENT          ACPI_UTILITIES
ACPI_MODULE_NAME("utids")

/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_execute_HID
 *
 * PARAMETERS:  device_node         - Node for the device
 *              return_id           - Where the string HID is returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Executes the _HID control method that returns the hardware
 *              ID of the device. The HID is either an 32-bit encoded EISAID
 *              Integer or a String. A string is always returned. An EISAID
 *              is converted to a string.
 *
 *              NOTE: Internal function, no parameter validation
 *
 ******************************************************************************/
acpi_status
acpi_ut_execute_HID(struct acpi_namespace_node *device_node,
            struct acpica_device_id **return_id)
{
    union acpi_operand_object *obj_desc;
    struct acpica_device_id *hid;
    u32 length;
    acpi_status status;

    ACPI_FUNCTION_TRACE(ut_execute_HID);

    status = acpi_ut_evaluate_object(device_node, METHOD_NAME__HID,
                     ACPI_BTYPE_INTEGER | ACPI_BTYPE_STRING,
                     &obj_desc);
    if (ACPI_FAILURE(status)) {
        return_ACPI_STATUS(status);
    }

    /* Get the size of the String to be returned, includes null terminator */

    if (obj_desc->common.type == ACPI_TYPE_INTEGER) {
        length = ACPI_EISAID_STRING_SIZE;
    } else {
        length = obj_desc->string.length + 1;
    }

    /* Allocate a buffer for the HID */

    hid =
        ACPI_ALLOCATE_ZEROED(sizeof(struct acpica_device_id) +
                 (acpi_size) length);
    if (!hid) {
        status = AE_NO_MEMORY;
        goto cleanup;
    }

    /* Area for the string starts after DEVICE_ID struct */

    hid->string = ACPI_ADD_PTR(char, hid, sizeof(struct acpica_device_id));

    /* Convert EISAID to a string or simply copy existing string */

    if (obj_desc->common.type == ACPI_TYPE_INTEGER) {
        acpi_ex_eisa_id_to_string(hid->string, obj_desc->integer.value);
    } else {
        ACPI_STRCPY(hid->string, obj_desc->string.pointer);
    }

    hid->length = length;
    *return_id = hid;

cleanup:

    /* On exit, we must delete the return object */

    acpi_ut_remove_reference(obj_desc);
    return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_execute_UID
 *
 * PARAMETERS:  device_node         - Node for the device
 *              return_id           - Where the string UID is returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Executes the _UID control method that returns the unique
 *              ID of the device. The UID is either a 64-bit Integer (NOT an
 *              EISAID) or a string. Always returns a string. A 64-bit integer
 *              is converted to a decimal string.
 *
 *              NOTE: Internal function, no parameter validation
 *
 ******************************************************************************/

acpi_status
acpi_ut_execute_UID(struct acpi_namespace_node *device_node,
            struct acpica_device_id **return_id)
{
    union acpi_operand_object *obj_desc;
    struct acpica_device_id *uid;
    u32 length;
    acpi_status status;

    ACPI_FUNCTION_TRACE(ut_execute_UID);

    status = acpi_ut_evaluate_object(device_node, METHOD_NAME__UID,
                     ACPI_BTYPE_INTEGER | ACPI_BTYPE_STRING,
                     &obj_desc);
    if (ACPI_FAILURE(status)) {
        return_ACPI_STATUS(status);
    }

    /* Get the size of the String to be returned, includes null terminator */

    if (obj_desc->common.type == ACPI_TYPE_INTEGER) {
        length = ACPI_MAX64_DECIMAL_DIGITS + 1;
    } else {
        length = obj_desc->string.length + 1;
    }

    /* Allocate a buffer for the UID */

    uid =
        ACPI_ALLOCATE_ZEROED(sizeof(struct acpica_device_id) +
                 (acpi_size) length);
    if (!uid) {
        status = AE_NO_MEMORY;
        goto cleanup;
    }

    /* Area for the string starts after DEVICE_ID struct */

    uid->string = ACPI_ADD_PTR(char, uid, sizeof(struct acpica_device_id));

    /* Convert an Integer to string, or just copy an existing string */

    if (obj_desc->common.type == ACPI_TYPE_INTEGER) {
        acpi_ex_integer_to_string(uid->string, obj_desc->integer.value);
    } else {
        ACPI_STRCPY(uid->string, obj_desc->string.pointer);
    }

    uid->length = length;
    *return_id = uid;

cleanup:

    /* On exit, we must delete the return object */

    acpi_ut_remove_reference(obj_desc);
    return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_execute_CID
 *
 * PARAMETERS:  device_node         - Node for the device
 *              return_cid_list     - Where the CID list is returned
 *
 * RETURN:      Status, list of CID strings
 *
 * DESCRIPTION: Executes the _CID control method that returns one or more
 *              compatible hardware IDs for the device.
 *
 *              NOTE: Internal function, no parameter validation
 *
 * A _CID method can return either a single compatible ID or a package of
 * compatible IDs. Each compatible ID can be one of the following:
 * 1) Integer (32 bit compressed EISA ID) or
 * 2) String (PCI ID format, e.g. "PCI\VEN_vvvv&DEV_dddd&SUBSYS_ssssssss")
 *
 * The Integer CIDs are converted to string format by this function.
 *
 ******************************************************************************/

acpi_status
acpi_ut_execute_CID(struct acpi_namespace_node *device_node,
            struct acpica_device_id_list **return_cid_list)
{
    union acpi_operand_object **cid_objects;
    union acpi_operand_object *obj_desc;
    struct acpica_device_id_list *cid_list;
    char *next_id_string;
    u32 string_area_size;
    u32 length;
    u32 cid_list_size;
    acpi_status status;
    u32 count;
    u32 i;

    ACPI_FUNCTION_TRACE(ut_execute_CID);

    /* Evaluate the _CID method for this device */

    status = acpi_ut_evaluate_object(device_node, METHOD_NAME__CID,
                     ACPI_BTYPE_INTEGER | ACPI_BTYPE_STRING
                     | ACPI_BTYPE_PACKAGE, &obj_desc);
    if (ACPI_FAILURE(status)) {
        return_ACPI_STATUS(status);
    }

    /*
     * Get the count and size of the returned _CIDs. _CID can return either
     * a Package of Integers/Strings or a single Integer or String.
     * Note: This section also validates that all CID elements are of the
     * correct type (Integer or String).
     */
    if (obj_desc->common.type == ACPI_TYPE_PACKAGE) {
        count = obj_desc->package.count;
        cid_objects = obj_desc->package.elements;
    } else {        /* Single Integer or String CID */

        count = 1;
        cid_objects = &obj_desc;
    }

    string_area_size = 0;
    for (i = 0; i < count; i++) {

        /* String lengths include null terminator */

        switch (cid_objects[i]->common.type) {
        case ACPI_TYPE_INTEGER:
            string_area_size += ACPI_EISAID_STRING_SIZE;
            break;

        case ACPI_TYPE_STRING:
            string_area_size += cid_objects[i]->string.length + 1;
            break;

        default:
            status = AE_TYPE;
            goto cleanup;
        }
    }

    /*
     * Now that we know the length of the CIDs, allocate return buffer:
     * 1) Size of the base structure +
     * 2) Size of the CID DEVICE_ID array +
     * 3) Size of the actual CID strings
     */
    cid_list_size = sizeof(struct acpica_device_id_list) +
        ((count - 1) * sizeof(struct acpica_device_id)) + string_area_size;

    cid_list = ACPI_ALLOCATE_ZEROED(cid_list_size);
    if (!cid_list) {
        status = AE_NO_MEMORY;
        goto cleanup;
    }

    /* Area for CID strings starts after the CID DEVICE_ID array */

    next_id_string = ACPI_CAST_PTR(char, cid_list->ids) +
        ((acpi_size) count * sizeof(struct acpica_device_id));

    /* Copy/convert the CIDs to the return buffer */

    for (i = 0; i < count; i++) {
        if (cid_objects[i]->common.type == ACPI_TYPE_INTEGER) {

            /* Convert the Integer (EISAID) CID to a string */

            acpi_ex_eisa_id_to_string(next_id_string,
                          cid_objects[i]->integer.
                          value);
            length = ACPI_EISAID_STRING_SIZE;
        } else {    /* ACPI_TYPE_STRING */

            /* Copy the String CID from the returned object */

            ACPI_STRCPY(next_id_string,
                    cid_objects[i]->string.pointer);
            length = cid_objects[i]->string.length + 1;
        }

        cid_list->ids[i].string = next_id_string;
        cid_list->ids[i].length = length;
        next_id_string += length;
    }

    /* Finish the CID list */

    cid_list->count = count;
    cid_list->list_size = cid_list_size;
    *return_cid_list = cid_list;

cleanup:

    /* On exit, we must delete the _CID return object */

    acpi_ut_remove_reference(obj_desc);
    return_ACPI_STATUS(status);
}