]>
Commit | Line | Data |
---|---|---|
fda8d26e | 1 | /* SPDX-License-Identifier: GPL-2.0-only */ |
670b19ae LPC |
2 | /* |
3 | * Copyright 2013-2015 Analog Devices Inc. | |
4 | * Author: Lars-Peter Clausen <lars@metafoo.de> | |
670b19ae LPC |
5 | */ |
6 | ||
7 | #ifndef __INDUSTRIALIO_DMA_BUFFER_H__ | |
8 | #define __INDUSTRIALIO_DMA_BUFFER_H__ | |
9 | ||
10 | #include <linux/list.h> | |
11 | #include <linux/kref.h> | |
12 | #include <linux/spinlock.h> | |
13 | #include <linux/mutex.h> | |
14 | #include <linux/iio/buffer.h> | |
15 | ||
16 | struct iio_dma_buffer_queue; | |
17 | struct iio_dma_buffer_ops; | |
18 | struct device; | |
19 | ||
20 | struct iio_buffer_block { | |
21 | u32 size; | |
22 | u32 bytes_used; | |
23 | }; | |
24 | ||
25 | /** | |
26 | * enum iio_block_state - State of a struct iio_dma_buffer_block | |
27 | * @IIO_BLOCK_STATE_DEQUEUED: Block is not queued | |
28 | * @IIO_BLOCK_STATE_QUEUED: Block is on the incoming queue | |
29 | * @IIO_BLOCK_STATE_ACTIVE: Block is currently being processed by the DMA | |
30 | * @IIO_BLOCK_STATE_DONE: Block is on the outgoing queue | |
31 | * @IIO_BLOCK_STATE_DEAD: Block has been marked as to be freed | |
32 | */ | |
33 | enum iio_block_state { | |
34 | IIO_BLOCK_STATE_DEQUEUED, | |
35 | IIO_BLOCK_STATE_QUEUED, | |
36 | IIO_BLOCK_STATE_ACTIVE, | |
37 | IIO_BLOCK_STATE_DONE, | |
38 | IIO_BLOCK_STATE_DEAD, | |
39 | }; | |
40 | ||
41 | /** | |
42 | * struct iio_dma_buffer_block - IIO buffer block | |
43 | * @head: List head | |
44 | * @size: Total size of the block in bytes | |
45 | * @bytes_used: Number of bytes that contain valid data | |
46 | * @vaddr: Virutal address of the blocks memory | |
47 | * @phys_addr: Physical address of the blocks memory | |
48 | * @queue: Parent DMA buffer queue | |
49 | * @kref: kref used to manage the lifetime of block | |
50 | * @state: Current state of the block | |
51 | */ | |
52 | struct iio_dma_buffer_block { | |
53 | /* May only be accessed by the owner of the block */ | |
54 | struct list_head head; | |
55 | size_t bytes_used; | |
56 | ||
57 | /* | |
58 | * Set during allocation, constant thereafter. May be accessed read-only | |
59 | * by anybody holding a reference to the block. | |
60 | */ | |
61 | void *vaddr; | |
62 | dma_addr_t phys_addr; | |
63 | size_t size; | |
64 | struct iio_dma_buffer_queue *queue; | |
65 | ||
66 | /* Must not be accessed outside the core. */ | |
67 | struct kref kref; | |
68 | /* | |
69 | * Must not be accessed outside the core. Access needs to hold | |
70 | * queue->list_lock if the block is not owned by the core. | |
71 | */ | |
72 | enum iio_block_state state; | |
73 | }; | |
74 | ||
75 | /** | |
76 | * struct iio_dma_buffer_queue_fileio - FileIO state for the DMA buffer | |
77 | * @blocks: Buffer blocks used for fileio | |
78 | * @active_block: Block being used in read() | |
79 | * @pos: Read offset in the active block | |
80 | * @block_size: Size of each block | |
81 | */ | |
82 | struct iio_dma_buffer_queue_fileio { | |
83 | struct iio_dma_buffer_block *blocks[2]; | |
84 | struct iio_dma_buffer_block *active_block; | |
85 | size_t pos; | |
86 | size_t block_size; | |
87 | }; | |
88 | ||
89 | /** | |
90 | * struct iio_dma_buffer_queue - DMA buffer base structure | |
91 | * @buffer: IIO buffer base structure | |
92 | * @dev: Parent device | |
93 | * @ops: DMA buffer callbacks | |
94 | * @lock: Protects the incoming list, active and the fields in the fileio | |
95 | * substruct | |
96 | * @list_lock: Protects lists that contain blocks which can be modified in | |
97 | * atomic context as well as blocks on those lists. This is the outgoing queue | |
98 | * list and typically also a list of active blocks in the part that handles | |
99 | * the DMA controller | |
100 | * @incoming: List of buffers on the incoming queue | |
101 | * @outgoing: List of buffers on the outgoing queue | |
102 | * @active: Whether the buffer is currently active | |
103 | * @fileio: FileIO state | |
104 | */ | |
105 | struct iio_dma_buffer_queue { | |
106 | struct iio_buffer buffer; | |
107 | struct device *dev; | |
108 | const struct iio_dma_buffer_ops *ops; | |
109 | ||
110 | struct mutex lock; | |
111 | spinlock_t list_lock; | |
112 | struct list_head incoming; | |
113 | struct list_head outgoing; | |
114 | ||
115 | bool active; | |
116 | ||
117 | struct iio_dma_buffer_queue_fileio fileio; | |
118 | }; | |
119 | ||
120 | /** | |
121 | * struct iio_dma_buffer_ops - DMA buffer callback operations | |
122 | * @submit: Called when a block is submitted to the DMA controller | |
123 | * @abort: Should abort all pending transfers | |
124 | */ | |
125 | struct iio_dma_buffer_ops { | |
126 | int (*submit)(struct iio_dma_buffer_queue *queue, | |
127 | struct iio_dma_buffer_block *block); | |
128 | void (*abort)(struct iio_dma_buffer_queue *queue); | |
129 | }; | |
130 | ||
131 | void iio_dma_buffer_block_done(struct iio_dma_buffer_block *block); | |
132 | void iio_dma_buffer_block_list_abort(struct iio_dma_buffer_queue *queue, | |
133 | struct list_head *list); | |
134 | ||
135 | int iio_dma_buffer_enable(struct iio_buffer *buffer, | |
136 | struct iio_dev *indio_dev); | |
137 | int iio_dma_buffer_disable(struct iio_buffer *buffer, | |
138 | struct iio_dev *indio_dev); | |
139 | int iio_dma_buffer_read(struct iio_buffer *buffer, size_t n, | |
140 | char __user *user_buffer); | |
141 | size_t iio_dma_buffer_data_available(struct iio_buffer *buffer); | |
142 | int iio_dma_buffer_set_bytes_per_datum(struct iio_buffer *buffer, size_t bpd); | |
92397a6c | 143 | int iio_dma_buffer_set_length(struct iio_buffer *buffer, unsigned int length); |
670b19ae LPC |
144 | int iio_dma_buffer_request_update(struct iio_buffer *buffer); |
145 | ||
146 | int iio_dma_buffer_init(struct iio_dma_buffer_queue *queue, | |
147 | struct device *dma_dev, const struct iio_dma_buffer_ops *ops); | |
148 | void iio_dma_buffer_exit(struct iio_dma_buffer_queue *queue); | |
149 | void iio_dma_buffer_release(struct iio_dma_buffer_queue *queue); | |
150 | ||
151 | #endif |