diff options
Diffstat (limited to 'chip/stm32/dma.h')
| -rw-r--r-- | chip/stm32/dma.h | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/chip/stm32/dma.h b/chip/stm32/dma.h index 81a4e1edd9..caf6c6228a 100644 --- a/chip/stm32/dma.h +++ b/chip/stm32/dma.h @@ -118,6 +118,19 @@ int dma_start_rx(unsigned channel, unsigned count, void *periph, void dma_disable(unsigned channel); /** + * Get the number of bytes available to read, or number of bytes written + * + * Since the DMA controller counts downwards, if we know the starting value + * we can work out how many bytes have been completed so far. + * + * @param chan DMA channel to check (use dma_get_channel()) + * @param orig_count Original number of bytes requested on channel + * @return number of bytes completed on a channel, or 0 if this channel is + * not enabled + */ +int dma_bytes_done(struct dma_channel *chan, int orig_count); + +/** * Start a previously-prepared dma channel * * @param chan Channel to start (returned from dma_prepare...()) |