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1/* SPDX-License-Identifier: GPL-2.0 */2/*3 * The contents of this file are private to DMA engine drivers, and is not4 * part of the API to be used by DMA engine users.5 */6#ifndef DMAENGINE_H7#define DMAENGINE_H8 9#include <linux/bug.h>10#include <linux/dmaengine.h>11 12/**13 * dma_cookie_init - initialize the cookies for a DMA channel14 * @chan: dma channel to initialize15 */16static 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 descriptor24 * @tx: descriptor needing cookie25 *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 */29static 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 descriptor44 * @tx: descriptor to complete45 *46 * Mark this descriptor complete by updating the channels completed47 * cookie marker. Zero the descriptors cookie to prevent accidental48 * repeated completions.49 *50 * Note: caller is expected to hold a lock to prevent concurrency.51 */52static 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 status61 * @chan: dma channel62 * @cookie: cookie we are interested in63 * @state: dma_tx_state structure to return last/used cookies64 *65 * Report the status of the cookie, filling in the state structure if66 * non-NULL. No locking is required.67 */68static 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, complete, used);83}84 85static inline void dma_set_residue(struct dma_tx_state *state, u32 residue)86{87 if (state)88 state->residue = residue;89}90 91static 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 98struct 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 function106 * @tx: tx descriptor107 * @cb: temp struct to hold the callback info108 *109 * Fill the passed in cb struct with what's available in the passed in110 * tx descriptor struct111 * No locking is required.112 */113static inline void114dmaengine_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 struct124 * @cb: temp struct that is holding the callback info125 * @result: transaction result126 *127 * Call the callback function provided in the cb struct with the parameter128 * in the cb struct.129 * Locking is dependent on the driver.130 */131static inline void132dmaengine_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 = 0138 };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 and151 * then immediately call the callback.152 * @tx: dma async tx descriptor153 * @result: transaction result154 *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 */159static inline void160dmaengine_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);166 dmaengine_desc_callback_invoke(&cb, result);167}168 169/**170 * dmaengine_desc_callback_valid - verify the callback is valid in cb171 * @cb: callback info struct172 *173 * Return a bool that verifies whether callback in cb is valid or not.174 * No locking is required.175 */176static inline bool177dmaengine_desc_callback_valid(struct dmaengine_desc_callback *cb)178{179 return cb->callback || cb->callback_result;180}181 182struct dma_chan *dma_get_slave_channel(struct dma_chan *chan);183struct dma_chan *dma_get_any_slave_channel(struct dma_device *device);184 185#ifdef CONFIG_DEBUG_FS186#include <linux/debugfs.h>187 188static inline struct dentry *189dmaengine_get_debugfs_root(struct dma_device *dma_dev) {190 return dma_dev->dbg_dev_root;191}192#else193struct dentry;194static inline struct dentry *195dmaengine_get_debugfs_root(struct dma_device *dma_dev)196{197 return NULL;198}199#endif /* CONFIG_DEBUG_FS */200 201#endif202