1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | /* |
3 | * The contents of this file are private to DMA engine drivers, and is not |
4 | * part of the API to be used by DMA engine users. |
5 | */ |
6 | #ifndef DMAENGINE_H |
7 | #define DMAENGINE_H |
8 | |
9 | #include <linux/bug.h> |
10 | #include <linux/dmaengine.h> |
11 | |
12 | /** |
13 | * dma_cookie_init - initialize the cookies for a DMA channel |
14 | * @chan: dma channel to initialize |
15 | */ |
16 | static inline void dma_cookie_init(struct dma_chan *chan) |
17 | { |
18 | chan->cookie = DMA_MIN_COOKIE; |
19 | chan->completed_cookie = DMA_MIN_COOKIE; |
20 | } |
21 | |
22 | /** |
23 | * dma_cookie_assign - assign a DMA engine cookie to the descriptor |
24 | * @tx: descriptor needing cookie |
25 | * |
26 | * Assign a unique non-zero per-channel cookie to the descriptor. |
27 | * Note: caller is expected to hold a lock to prevent concurrency. |
28 | */ |
29 | static inline dma_cookie_t dma_cookie_assign(struct dma_async_tx_descriptor *tx) |
30 | { |
31 | struct dma_chan *chan = tx->chan; |
32 | dma_cookie_t cookie; |
33 | |
34 | cookie = chan->cookie + 1; |
35 | if (cookie < DMA_MIN_COOKIE) |
36 | cookie = DMA_MIN_COOKIE; |
37 | tx->cookie = chan->cookie = cookie; |
38 | |
39 | return cookie; |
40 | } |
41 | |
42 | /** |
43 | * dma_cookie_complete - complete a descriptor |
44 | * @tx: descriptor to complete |
45 | * |
46 | * Mark this descriptor complete by updating the channels completed |
47 | * cookie marker. Zero the descriptors cookie to prevent accidental |
48 | * repeated completions. |
49 | * |
50 | * Note: caller is expected to hold a lock to prevent concurrency. |
51 | */ |
52 | static inline void dma_cookie_complete(struct dma_async_tx_descriptor *tx) |
53 | { |
54 | BUG_ON(tx->cookie < DMA_MIN_COOKIE); |
55 | tx->chan->completed_cookie = tx->cookie; |
56 | tx->cookie = 0; |
57 | } |
58 | |
59 | /** |
60 | * dma_cookie_status - report cookie status |
61 | * @chan: dma channel |
62 | * @cookie: cookie we are interested in |
63 | * @state: dma_tx_state structure to return last/used cookies |
64 | * |
65 | * Report the status of the cookie, filling in the state structure if |
66 | * non-NULL. No locking is required. |
67 | */ |
68 | static inline enum dma_status dma_cookie_status(struct dma_chan *chan, |
69 | dma_cookie_t cookie, struct dma_tx_state *state) |
70 | { |
71 | dma_cookie_t used, complete; |
72 | |
73 | used = chan->cookie; |
74 | complete = chan->completed_cookie; |
75 | barrier(); |
76 | if (state) { |
77 | state->last = complete; |
78 | state->used = used; |
79 | state->residue = 0; |
80 | state->in_flight_bytes = 0; |
81 | } |
82 | return dma_async_is_complete(cookie, last_complete: complete, last_used: used); |
83 | } |
84 | |
85 | static inline void dma_set_residue(struct dma_tx_state *state, u32 residue) |
86 | { |
87 | if (state) |
88 | state->residue = residue; |
89 | } |
90 | |
91 | static inline void dma_set_in_flight_bytes(struct dma_tx_state *state, |
92 | u32 in_flight_bytes) |
93 | { |
94 | if (state) |
95 | state->in_flight_bytes = in_flight_bytes; |
96 | } |
97 | |
98 | struct dmaengine_desc_callback { |
99 | dma_async_tx_callback callback; |
100 | dma_async_tx_callback_result callback_result; |
101 | void *callback_param; |
102 | }; |
103 | |
104 | /** |
105 | * dmaengine_desc_get_callback - get the passed in callback function |
106 | * @tx: tx descriptor |
107 | * @cb: temp struct to hold the callback info |
108 | * |
109 | * Fill the passed in cb struct with what's available in the passed in |
110 | * tx descriptor struct |
111 | * No locking is required. |
112 | */ |
113 | static inline void |
114 | dmaengine_desc_get_callback(struct dma_async_tx_descriptor *tx, |
115 | struct dmaengine_desc_callback *cb) |
116 | { |
117 | cb->callback = tx->callback; |
118 | cb->callback_result = tx->callback_result; |
119 | cb->callback_param = tx->callback_param; |
120 | } |
121 | |
122 | /** |
123 | * dmaengine_desc_callback_invoke - call the callback function in cb struct |
124 | * @cb: temp struct that is holding the callback info |
125 | * @result: transaction result |
126 | * |
127 | * Call the callback function provided in the cb struct with the parameter |
128 | * in the cb struct. |
129 | * Locking is dependent on the driver. |
130 | */ |
131 | static inline void |
132 | dmaengine_desc_callback_invoke(struct dmaengine_desc_callback *cb, |
133 | const struct dmaengine_result *result) |
134 | { |
135 | struct dmaengine_result dummy_result = { |
136 | .result = DMA_TRANS_NOERROR, |
137 | .residue = 0 |
138 | }; |
139 | |
140 | if (cb->callback_result) { |
141 | if (!result) |
142 | result = &dummy_result; |
143 | cb->callback_result(cb->callback_param, result); |
144 | } else if (cb->callback) { |
145 | cb->callback(cb->callback_param); |
146 | } |
147 | } |
148 | |
149 | /** |
150 | * dmaengine_desc_get_callback_invoke - get the callback in tx descriptor and |
151 | * then immediately call the callback. |
152 | * @tx: dma async tx descriptor |
153 | * @result: transaction result |
154 | * |
155 | * Call dmaengine_desc_get_callback() and dmaengine_desc_callback_invoke() |
156 | * in a single function since no work is necessary in between for the driver. |
157 | * Locking is dependent on the driver. |
158 | */ |
159 | static inline void |
160 | dmaengine_desc_get_callback_invoke(struct dma_async_tx_descriptor *tx, |
161 | const struct dmaengine_result *result) |
162 | { |
163 | struct dmaengine_desc_callback cb; |
164 | |
165 | dmaengine_desc_get_callback(tx, cb: &cb); |
166 | dmaengine_desc_callback_invoke(cb: &cb, result); |
167 | } |
168 | |
169 | /** |
170 | * dmaengine_desc_callback_valid - verify the callback is valid in cb |
171 | * @cb: callback info struct |
172 | * |
173 | * Return a bool that verifies whether callback in cb is valid or not. |
174 | * No locking is required. |
175 | */ |
176 | static inline bool |
177 | dmaengine_desc_callback_valid(struct dmaengine_desc_callback *cb) |
178 | { |
179 | return cb->callback || cb->callback_result; |
180 | } |
181 | |
182 | struct dma_chan *dma_get_slave_channel(struct dma_chan *chan); |
183 | struct dma_chan *dma_get_any_slave_channel(struct dma_device *device); |
184 | |
185 | #ifdef CONFIG_DEBUG_FS |
186 | #include <linux/debugfs.h> |
187 | |
188 | static inline struct dentry * |
189 | dmaengine_get_debugfs_root(struct dma_device *dma_dev) { |
190 | return dma_dev->dbg_dev_root; |
191 | } |
192 | #else |
193 | struct dentry; |
194 | static inline struct dentry * |
195 | dmaengine_get_debugfs_root(struct dma_device *dma_dev) |
196 | { |
197 | return NULL; |
198 | } |
199 | #endif /* CONFIG_DEBUG_FS */ |
200 | |
201 | #endif |
202 | |