diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c index 75ec0754d4ad..330ff41cd614 100644 --- a/drivers/dma/imx-sdma.c +++ b/drivers/dma/imx-sdma.c @@ -701,6 +701,11 @@ static int sdma_config_ownership(struct sdma_channel *sdmac, return 0; } +static int is_sdma_channel_enabled(struct sdma_engine *sdma, int channel) +{ + return !!(readl(sdma->regs + SDMA_H_STATSTOP) & BIT(channel)); +} + static void sdma_enable_channel(struct sdma_engine *sdma, int channel) { writel(BIT(channel), sdma->regs + SDMA_H_START); @@ -860,6 +865,15 @@ static void sdma_update_channel_loop(struct sdma_channel *sdmac) if (error) sdmac->status = old_status; } + + /* + * SDMA stops cyclic channel when DMA request triggers a channel and no SDMA + * owned buffer is available (i.e. BD_DONE was set too late). + */ + if (!is_sdma_channel_enabled(sdmac->sdma, sdmac->channel)) { + dev_warn(sdmac->sdma->dev, "restart cyclic channel %d\n", sdmac->channel); + sdma_enable_channel(sdmac->sdma, sdmac->channel); + } } static void mxc_sdma_handle_channel_normal(struct sdma_channel *data)