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-rw-r--r--drivers/dma/fsldma.c45
-rw-r--r--drivers/dma/fsldma.h3
2 files changed, 31 insertions, 17 deletions
diff --git a/drivers/dma/fsldma.c b/drivers/dma/fsldma.c
index 73dd74823195..7a0cb6064f83 100644
--- a/drivers/dma/fsldma.c
+++ b/drivers/dma/fsldma.c
@@ -280,28 +280,40 @@ static void fsl_chan_set_dest_loop_size(struct fsl_dma_chan *fsl_chan, int size)
}
/**
- * fsl_chan_toggle_ext_pause - Toggle channel external pause status
+ * fsl_chan_set_request_count - Set DMA Request Count for external control
* @fsl_chan : Freescale DMA channel
- * @size : Pause control size, 0 for disable external pause control.
- * The maximum is 1024.
+ * @size : Number of bytes to transfer in a single request
+ *
+ * The Freescale DMA channel can be controlled by the external signal DREQ#.
+ * The DMA request count is how many bytes are allowed to transfer before
+ * pausing the channel, after which a new assertion of DREQ# resumes channel
+ * operation.
*
- * The Freescale DMA channel can be controlled by the external
- * signal DREQ#. The pause control size is how many bytes are allowed
- * to transfer before pausing the channel, after which a new assertion
- * of DREQ# resumes channel operation.
+ * A size of 0 disables external pause control. The maximum size is 1024.
*/
-static void fsl_chan_toggle_ext_pause(struct fsl_dma_chan *fsl_chan, int size)
+static void fsl_chan_set_request_count(struct fsl_dma_chan *fsl_chan, int size)
{
- if (size > 1024)
- return;
+ BUG_ON(size > 1024);
+ DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
+ DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32)
+ | ((__ilog2(size) << 24) & 0x0f000000),
+ 32);
+}
- if (size) {
- DMA_OUT(fsl_chan, &fsl_chan->reg_base->mr,
- DMA_IN(fsl_chan, &fsl_chan->reg_base->mr, 32)
- | ((__ilog2(size) << 24) & 0x0f000000),
- 32);
+/**
+ * fsl_chan_toggle_ext_pause - Toggle channel external pause status
+ * @fsl_chan : Freescale DMA channel
+ * @enable : 0 is disabled, 1 is enabled.
+ *
+ * The Freescale DMA channel can be controlled by the external signal DREQ#.
+ * The DMA Request Count feature should be used in addition to this feature
+ * to set the number of bytes to transfer before pausing the channel.
+ */
+static void fsl_chan_toggle_ext_pause(struct fsl_dma_chan *fsl_chan, int enable)
+{
+ if (enable)
fsl_chan->feature |= FSL_DMA_CHAN_PAUSE_EXT;
- } else
+ else
fsl_chan->feature &= ~FSL_DMA_CHAN_PAUSE_EXT;
}
@@ -885,6 +897,7 @@ static int __devinit fsl_dma_chan_probe(struct fsl_dma_device *fdev,
new_fsl_chan->toggle_ext_start = fsl_chan_toggle_ext_start;
new_fsl_chan->set_src_loop_size = fsl_chan_set_src_loop_size;
new_fsl_chan->set_dest_loop_size = fsl_chan_set_dest_loop_size;
+ new_fsl_chan->set_request_count = fsl_chan_set_request_count;
}
spin_lock_init(&new_fsl_chan->desc_lock);
diff --git a/drivers/dma/fsldma.h b/drivers/dma/fsldma.h
index 4493afed53f0..0df14cbb8ca3 100644
--- a/drivers/dma/fsldma.h
+++ b/drivers/dma/fsldma.h
@@ -144,10 +144,11 @@ struct fsl_dma_chan {
struct tasklet_struct tasklet;
u32 feature;
- void (*toggle_ext_pause)(struct fsl_dma_chan *fsl_chan, int size);
+ void (*toggle_ext_pause)(struct fsl_dma_chan *fsl_chan, int enable);
void (*toggle_ext_start)(struct fsl_dma_chan *fsl_chan, int enable);
void (*set_src_loop_size)(struct fsl_dma_chan *fsl_chan, int size);
void (*set_dest_loop_size)(struct fsl_dma_chan *fsl_chan, int size);
+ void (*set_request_count)(struct fsl_dma_chan *fsl_chan, int size);
};
#define to_fsl_chan(chan) container_of(chan, struct fsl_dma_chan, common)