v4.19.13 snapshot.
diff --git a/drivers/dma/dmaengine.h b/drivers/dma/dmaengine.h
new file mode 100644
index 0000000..501c0b0
--- /dev/null
+++ b/drivers/dma/dmaengine.h
@@ -0,0 +1,174 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * The contents of this file are private to DMA engine drivers, and is not
+ * part of the API to be used by DMA engine users.
+ */
+#ifndef DMAENGINE_H
+#define DMAENGINE_H
+
+#include <linux/bug.h>
+#include <linux/dmaengine.h>
+
+/**
+ * dma_cookie_init - initialize the cookies for a DMA channel
+ * @chan: dma channel to initialize
+ */
+static inline void dma_cookie_init(struct dma_chan *chan)
+{
+ chan->cookie = DMA_MIN_COOKIE;
+ chan->completed_cookie = DMA_MIN_COOKIE;
+}
+
+/**
+ * dma_cookie_assign - assign a DMA engine cookie to the descriptor
+ * @tx: descriptor needing cookie
+ *
+ * Assign a unique non-zero per-channel cookie to the descriptor.
+ * Note: caller is expected to hold a lock to prevent concurrency.
+ */
+static inline dma_cookie_t dma_cookie_assign(struct dma_async_tx_descriptor *tx)
+{
+ struct dma_chan *chan = tx->chan;
+ dma_cookie_t cookie;
+
+ cookie = chan->cookie + 1;
+ if (cookie < DMA_MIN_COOKIE)
+ cookie = DMA_MIN_COOKIE;
+ tx->cookie = chan->cookie = cookie;
+
+ return cookie;
+}
+
+/**
+ * dma_cookie_complete - complete a descriptor
+ * @tx: descriptor to complete
+ *
+ * Mark this descriptor complete by updating the channels completed
+ * cookie marker. Zero the descriptors cookie to prevent accidental
+ * repeated completions.
+ *
+ * Note: caller is expected to hold a lock to prevent concurrency.
+ */
+static inline void dma_cookie_complete(struct dma_async_tx_descriptor *tx)
+{
+ BUG_ON(tx->cookie < DMA_MIN_COOKIE);
+ tx->chan->completed_cookie = tx->cookie;
+ tx->cookie = 0;
+}
+
+/**
+ * dma_cookie_status - report cookie status
+ * @chan: dma channel
+ * @cookie: cookie we are interested in
+ * @state: dma_tx_state structure to return last/used cookies
+ *
+ * Report the status of the cookie, filling in the state structure if
+ * non-NULL. No locking is required.
+ */
+static inline enum dma_status dma_cookie_status(struct dma_chan *chan,
+ dma_cookie_t cookie, struct dma_tx_state *state)
+{
+ dma_cookie_t used, complete;
+
+ used = chan->cookie;
+ complete = chan->completed_cookie;
+ barrier();
+ if (state) {
+ state->last = complete;
+ state->used = used;
+ state->residue = 0;
+ }
+ return dma_async_is_complete(cookie, complete, used);
+}
+
+static inline void dma_set_residue(struct dma_tx_state *state, u32 residue)
+{
+ if (state)
+ state->residue = residue;
+}
+
+struct dmaengine_desc_callback {
+ dma_async_tx_callback callback;
+ dma_async_tx_callback_result callback_result;
+ void *callback_param;
+};
+
+/**
+ * dmaengine_desc_get_callback - get the passed in callback function
+ * @tx: tx descriptor
+ * @cb: temp struct to hold the callback info
+ *
+ * Fill the passed in cb struct with what's available in the passed in
+ * tx descriptor struct
+ * No locking is required.
+ */
+static inline void
+dmaengine_desc_get_callback(struct dma_async_tx_descriptor *tx,
+ struct dmaengine_desc_callback *cb)
+{
+ cb->callback = tx->callback;
+ cb->callback_result = tx->callback_result;
+ cb->callback_param = tx->callback_param;
+}
+
+/**
+ * dmaengine_desc_callback_invoke - call the callback function in cb struct
+ * @cb: temp struct that is holding the callback info
+ * @result: transaction result
+ *
+ * Call the callback function provided in the cb struct with the parameter
+ * in the cb struct.
+ * Locking is dependent on the driver.
+ */
+static inline void
+dmaengine_desc_callback_invoke(struct dmaengine_desc_callback *cb,
+ const struct dmaengine_result *result)
+{
+ struct dmaengine_result dummy_result = {
+ .result = DMA_TRANS_NOERROR,
+ .residue = 0
+ };
+
+ if (cb->callback_result) {
+ if (!result)
+ result = &dummy_result;
+ cb->callback_result(cb->callback_param, result);
+ } else if (cb->callback) {
+ cb->callback(cb->callback_param);
+ }
+}
+
+/**
+ * dmaengine_desc_get_callback_invoke - get the callback in tx descriptor and
+ * then immediately call the callback.
+ * @tx: dma async tx descriptor
+ * @result: transaction result
+ *
+ * Call dmaengine_desc_get_callback() and dmaengine_desc_callback_invoke()
+ * in a single function since no work is necessary in between for the driver.
+ * Locking is dependent on the driver.
+ */
+static inline void
+dmaengine_desc_get_callback_invoke(struct dma_async_tx_descriptor *tx,
+ const struct dmaengine_result *result)
+{
+ struct dmaengine_desc_callback cb;
+
+ dmaengine_desc_get_callback(tx, &cb);
+ dmaengine_desc_callback_invoke(&cb, result);
+}
+
+/**
+ * dmaengine_desc_callback_valid - verify the callback is valid in cb
+ * @cb: callback info struct
+ *
+ * Return a bool that verifies whether callback in cb is valid or not.
+ * No locking is required.
+ */
+static inline bool
+dmaengine_desc_callback_valid(struct dmaengine_desc_callback *cb)
+{
+ return (cb->callback) ? true : false;
+}
+
+#endif