diff options
Diffstat (limited to 'nuttx/arch/arm/src/stm32/stm32f40xxx_dma.c')
| -rw-r--r-- | nuttx/arch/arm/src/stm32/stm32f40xxx_dma.c | 11 |
1 files changed, 7 insertions, 4 deletions
diff --git a/nuttx/arch/arm/src/stm32/stm32f40xxx_dma.c b/nuttx/arch/arm/src/stm32/stm32f40xxx_dma.c index dcbbf1856..40fce8cb5 100644 --- a/nuttx/arch/arm/src/stm32/stm32f40xxx_dma.c +++ b/nuttx/arch/arm/src/stm32/stm32f40xxx_dma.c @@ -94,7 +94,6 @@ struct stm32_dma_s uint8_t irq; /* DMA stream IRQ number */ uint8_t shift; /* ISR/IFCR bit shift value */ uint8_t channel; /* DMA channel number (0-7) */ - bool nonstop; /* Stream is configured in a non-stopping mode. */ sem_t sem; /* Used to wait for DMA channel to become available */ uint32_t base; /* DMA register channel base address */ dma_callback_t callback; /* Callback invoked when the DMA completes */ @@ -728,7 +727,6 @@ void stm32_dmasetup(DMA_HANDLE handle, uint32_t paddr, uint32_t maddr, DMA_SCR_DBM|DMA_SCR_CIRC| DMA_SCR_PBURST_MASK|DMA_SCR_MBURST_MASK); regval |= scr; - dmast->nonstop = (scr & (DMA_SCR_DBM|DMA_SCR_CIRC)) != 0; dmast_putreg(dmast, STM32_DMA_SCR_OFFSET, regval); } @@ -764,7 +762,12 @@ void stm32_dmastart(DMA_HANDLE handle, dma_callback_t callback, void *arg, bool scr = dmast_getreg(dmast, STM32_DMA_SCR_OFFSET); scr |= DMA_SCR_EN; - if (!dmast->nonstop) + /* In normal mode, interrupt at either half or full completion. In circular + * and double-buffered modes, always interrupt on buffer wrap, and optionally + * interrupt at the halfway point. + */ + + if ((scr & (DMA_SCR_DBM|DMA_SCR_CIRC)) == 0) { /* Once half of the bytes are transferred, the half-transfer flag (HTIF) is * set and an interrupt is generated if the Half-Transfer Interrupt Enable @@ -777,7 +780,7 @@ void stm32_dmastart(DMA_HANDLE handle, dma_callback_t callback, void *arg, bool } else { - /* In nonstop mode, when the transfer completes it immediately resets + /* In non-stop modes, when the transfer completes it immediately resets * and starts again. The transfer-complete interrupt is thus always * enabled, and the half-complete interrupt can be used in circular * mode to determine when the buffer is half-full, or in double-buffered |