diff options
Diffstat (limited to 'drivers/dma')
| -rw-r--r-- | drivers/dma/fsldma.c | 45 | ||||
| -rw-r--r-- | drivers/dma/fsldma.h | 3 |
2 files changed, 31 insertions, 17 deletions
diff --git a/drivers/dma/fsldma.c b/drivers/dma/fsldma.c index 73dd7482319..7a0cb6064f8 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 4493afed53f..0df14cbb8ca 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) |