LXR linux/drivers/dma/dw/acpi.c

   1// SPDX-License-Identifier: GPL-2.0
   2// Copyright (C) 2013,2019 Intel Corporation
   3
   4#include <linux/acpi.h>
   5#include <linux/acpi_dma.h>
   6
   7#include "internal.h"
   8
   9static bool dw_dma_acpi_filter(struct dma_chan *chan, void *param)
  10{
  11        struct acpi_dma_spec *dma_spec = param;
  12        struct dw_dma_slave slave = {
  13                .dma_dev = dma_spec->dev,
  14                .src_id = dma_spec->slave_id,
  15                .dst_id = dma_spec->slave_id,
  16                .m_master = 0,
  17                .p_master = 1,
  18        };
  19
  20        return dw_dma_filter(chan, &slave);
  21}
  22
  23void dw_dma_acpi_controller_register(struct dw_dma *dw)
  24{
  25        struct device *dev = dw->dma.dev;
  26        struct acpi_dma_filter_info *info;
  27        int ret;
  28
  29        if (!has_acpi_companion(dev))
  30                return;
  31
  32        info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
  33        if (!info)
  34                return;
  35
  36        dma_cap_zero(info->dma_cap);
  37        dma_cap_set(DMA_SLAVE, info->dma_cap);
  38        info->filter_fn = dw_dma_acpi_filter;
  39
  40        ret = acpi_dma_controller_register(dev, acpi_dma_simple_xlate, info);
  41        if (ret)
  42                dev_err(dev, "could not register acpi_dma_controller\n");
  43}
  44EXPORT_SYMBOL_GPL(dw_dma_acpi_controller_register);
  45
  46void dw_dma_acpi_controller_free(struct dw_dma *dw)
  47{
  48        struct device *dev = dw->dma.dev;
  49
  50        if (!has_acpi_companion(dev))
  51                return;
  52
  53        acpi_dma_controller_free(dev);
  54}
  55EXPORT_SYMBOL_GPL(dw_dma_acpi_controller_free);
  56