1 | /* SPDX-License-Identifier: GPL-2.0-only */ |
2 | /* |
3 | * ACPI helpers for DMA request / controller |
4 | * |
5 | * Based on of_dma.h |
6 | * |
7 | * Copyright (C) 2013, Intel Corporation |
8 | * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com> |
9 | */ |
10 | |
11 | #ifndef __LINUX_ACPI_DMA_H |
12 | #define __LINUX_ACPI_DMA_H |
13 | |
14 | #include <linux/list.h> |
15 | #include <linux/device.h> |
16 | #include <linux/err.h> |
17 | #include <linux/dmaengine.h> |
18 | |
19 | /** |
20 | * struct acpi_dma_spec - slave device DMA resources |
21 | * @chan_id: channel unique id |
22 | * @slave_id: request line unique id |
23 | * @dev: struct device of the DMA controller to be used in the filter |
24 | * function |
25 | */ |
26 | struct acpi_dma_spec { |
27 | int chan_id; |
28 | int slave_id; |
29 | struct device *dev; |
30 | }; |
31 | |
32 | /** |
33 | * struct acpi_dma - representation of the registered DMAC |
34 | * @dma_controllers: linked list node |
35 | * @dev: struct device of this controller |
36 | * @acpi_dma_xlate: callback function to find a suitable channel |
37 | * @data: private data used by a callback function |
38 | * @base_request_line: first supported request line (CSRT) |
39 | * @end_request_line: last supported request line (CSRT) |
40 | */ |
41 | struct acpi_dma { |
42 | struct list_head dma_controllers; |
43 | struct device *dev; |
44 | struct dma_chan *(*acpi_dma_xlate) |
45 | (struct acpi_dma_spec *, struct acpi_dma *); |
46 | void *data; |
47 | unsigned short base_request_line; |
48 | unsigned short end_request_line; |
49 | }; |
50 | |
51 | /* Used with acpi_dma_simple_xlate() */ |
52 | struct acpi_dma_filter_info { |
53 | dma_cap_mask_t dma_cap; |
54 | dma_filter_fn filter_fn; |
55 | }; |
56 | |
57 | #ifdef CONFIG_DMA_ACPI |
58 | |
59 | int acpi_dma_controller_register(struct device *dev, |
60 | struct dma_chan *(*acpi_dma_xlate) |
61 | (struct acpi_dma_spec *, struct acpi_dma *), |
62 | void *data); |
63 | int acpi_dma_controller_free(struct device *dev); |
64 | int devm_acpi_dma_controller_register(struct device *dev, |
65 | struct dma_chan *(*acpi_dma_xlate) |
66 | (struct acpi_dma_spec *, struct acpi_dma *), |
67 | void *data); |
68 | void devm_acpi_dma_controller_free(struct device *dev); |
69 | |
70 | struct dma_chan *acpi_dma_request_slave_chan_by_index(struct device *dev, |
71 | size_t index); |
72 | struct dma_chan *acpi_dma_request_slave_chan_by_name(struct device *dev, |
73 | const char *name); |
74 | |
75 | struct dma_chan *acpi_dma_simple_xlate(struct acpi_dma_spec *dma_spec, |
76 | struct acpi_dma *adma); |
77 | #else |
78 | |
79 | static inline int acpi_dma_controller_register(struct device *dev, |
80 | struct dma_chan *(*acpi_dma_xlate) |
81 | (struct acpi_dma_spec *, struct acpi_dma *), |
82 | void *data) |
83 | { |
84 | return -ENODEV; |
85 | } |
86 | static inline int acpi_dma_controller_free(struct device *dev) |
87 | { |
88 | return -ENODEV; |
89 | } |
90 | static inline int devm_acpi_dma_controller_register(struct device *dev, |
91 | struct dma_chan *(*acpi_dma_xlate) |
92 | (struct acpi_dma_spec *, struct acpi_dma *), |
93 | void *data) |
94 | { |
95 | return -ENODEV; |
96 | } |
97 | static inline void devm_acpi_dma_controller_free(struct device *dev) |
98 | { |
99 | } |
100 | |
101 | static inline struct dma_chan *acpi_dma_request_slave_chan_by_index( |
102 | struct device *dev, size_t index) |
103 | { |
104 | return ERR_PTR(-ENODEV); |
105 | } |
106 | static inline struct dma_chan *acpi_dma_request_slave_chan_by_name( |
107 | struct device *dev, const char *name) |
108 | { |
109 | return ERR_PTR(-ENODEV); |
110 | } |
111 | |
112 | #define acpi_dma_simple_xlate NULL |
113 | |
114 | #endif |
115 | |
116 | #define acpi_dma_request_slave_channel acpi_dma_request_slave_chan_by_index |
117 | |
118 | #endif /* __LINUX_ACPI_DMA_H */ |
119 | |