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, param: &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, size: 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_xlate: acpi_dma_simple_xlate, data: 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

source code of linux/drivers/dma/dw/acpi.c