[PATCH 3/4] Extend the DMA-engine API.
From: Zhang Wei <hidden>
Date: 2007-07-10 09:37:55
Add channel wait queue and transfer callback dma_xfer_callback(). If the DMA controller and driver support interrupt, when the transfer is finished, it will wakeup the wait queue and call the callback function of the channel. Add dma_async_raw_xfer() to API and device_raw_xfer() to struct dma_device for RAW physical address DMA transfer, which will be used at transfer between I/O address and memory address. Signed-off-by: Zhang Wei <redacted> --- include/linux/dmaengine.h | 35 +++++++++++++++++++++++++++++++++++ 1 files changed, 35 insertions(+), 0 deletions(-)
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index c94d8f1..d9dfc57 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h@@ -28,6 +28,7 @@ #include <linux/kref.h> #include <linux/completion.h> #include <linux/rcupdate.h> +#include <linux/wait.h> /** * enum dma_event - resource PNP/power managment events
@@ -108,6 +109,8 @@ struct dma_chan { struct list_head client_node; struct list_head device_node; struct dma_chan_percpu *local; + + wait_queue_head_t wait_q; }; void dma_chan_cleanup(struct kref *kref);
@@ -138,6 +141,12 @@ static inline void dma_chan_put(struct dma_chan *chan) typedef void (*dma_event_callback) (struct dma_client *client, struct dma_chan *chan, enum dma_event event); +/* + * typedef dma_xfer_callback + * - function pointer to a DMA transfer callback when finished + */ +typedef void (*dma_xfer_callback) (struct dma_chan *chan, void *data); + /** * struct dma_client - info on the entity making use of DMA services * @event_callback: func ptr to call when something happens
@@ -187,6 +196,9 @@ struct dma_device { int (*device_alloc_chan_resources)(struct dma_chan *chan); void (*device_free_chan_resources)(struct dma_chan *chan); + dma_cookie_t (*device_raw_xfer)(struct dma_chan *chan, + dma_addr_t dest, dma_addr_t src, size_t len, + dma_xfer_callback cb, void *data); dma_cookie_t (*device_memcpy_buf_to_buf)(struct dma_chan *chan, void *dest, void *src, size_t len); dma_cookie_t (*device_memcpy_buf_to_pg)(struct dma_chan *chan,
@@ -209,6 +221,29 @@ void dma_async_client_chan_request(struct dma_client *client, unsigned int number); /** + * dma_async_raw_xfer - transfor data between physical addresses with callback + * @chan: DMA channel to be used + * @dest: destination address (physical) + * @src: source address (physical) + * @len: length + */ +static inline dma_cookie_t dma_async_raw_xfer(struct dma_chan *chan, + dma_addr_t dest, dma_addr_t src, size_t len, + dma_xfer_callback cb, void *data) +{ + int cpu = get_cpu(); + per_cpu_ptr(chan->local, cpu)->bytes_transferred += len; + per_cpu_ptr(chan->local, cpu)->memcpy_count++; + put_cpu(); + + if (chan->device->device_raw_xfer) + return chan->device->device_raw_xfer(chan, dest, src, len, + cb, data); + else + return -EPERM; +} + +/** * dma_async_memcpy_buf_to_buf - offloaded copy between virtual addresses * @chan: DMA channel to offload copy to * @dest: destination address (virtual)
--
1.5.1