xref: /openbmc/linux/drivers/dma/dw/acpi.c (revision 95298d63)
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 
9 static 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 
23 void 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 }
44 
45 void dw_dma_acpi_controller_free(struct dw_dma *dw)
46 {
47 	struct device *dev = dw->dma.dev;
48 
49 	if (!has_acpi_companion(dev))
50 		return;
51 
52 	acpi_dma_controller_free(dev);
53 }
54