linux-imx

/*

 * ACPI helpers for DMA request / controller

 *

 * Based on of-dma.c

 *

 * Copyright (C) 2013, Intel Corporation

 * Authors: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

 *      Mika Westerberg <mika.westerberg@linux.intel.com>

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 */

​

#include <linux/device.h>

#include <linux/err.h>

#include <linux/module.h>

#include <linux/kernel.h>

#include <linux/list.h>

#include <linux/mutex.h>

#include <linux/slab.h>

#include <linux/ioport.h>

#include <linux/acpi.h>

#include <linux/acpi_dma.h>

#include <linux/property.h>

​

static LIST_HEAD(acpi_dma_list);

static DEFINE_MUTEX(acpi_dma_lock);

​

/**

 * acpi_dma_parse_resource_group - match device and parse resource group

 * @grp:    CSRT resource group

 * @adev:   ACPI device to match with

 * @adma:   struct acpi_dma of the given DMA controller

 *

 * In order to match a device from DSDT table to the corresponding CSRT device

 * we use MMIO address and IRQ.

 *

 * Return:

 * 1 on success, 0 when no information is available, or appropriate errno value

 * on error.

 */

static int acpi_dma_parse_resource_group(const struct acpi_csrt_group *grp,

        struct acpi_device *adev, struct acpi_dma *adma)

{

    const struct acpi_csrt_shared_info *si;

    struct list_head resource_list;

    struct resource_entry *rentry;

    resource_size_t mem = 0, irq = 0;

    int ret;

​

    if (grp->shared_info_length != sizeof(struct acpi_csrt_shared_info))

        return -ENODEV;

​

    INIT_LIST_HEAD(&resource_list);

    ret = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);

    if (ret <= 0)

        return 0;

​

    list_for_each_entry(rentry, &resource_list, node) {

        if (resource_type(rentry->res) == IORESOURCE_MEM)

            mem = rentry->res->start;

        else if (resource_type(rentry->res) == IORESOURCE_IRQ)