We should runtime resume the device before calling axi_chan_is_hw_enable(), otherwise we may see cpu aborts when accessing registers in axi_chan_is_hw_enable(). Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxx> --- drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c index 796b6caf0bab..203be13499e3 100644 --- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c +++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c @@ -469,13 +469,17 @@ static void dw_axi_dma_synchronize(struct dma_chan *dchan) static int dma_chan_alloc_chan_resources(struct dma_chan *dchan) { + int ret; struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan); + pm_runtime_get(chan->chip->dev); + /* ASSERT: channel is idle */ if (axi_chan_is_hw_enable(chan)) { dev_err(chan2dev(chan), "%s is non-idle!\n", axi_chan_name(chan)); - return -EBUSY; + ret = -EBUSY; + goto err_busy; } /* LLI address must be aligned to a 64-byte boundary */ @@ -485,13 +489,16 @@ static int dma_chan_alloc_chan_resources(struct dma_chan *dchan) 64, 0); if (!chan->desc_pool) { dev_err(chan2dev(chan), "No memory for descriptors\n"); - return -ENOMEM; + ret = -ENOMEM; + goto err_busy; } dev_vdbg(dchan2dev(dchan), "%s: allocating\n", axi_chan_name(chan)); - pm_runtime_get(chan->chip->dev); - return 0; + +err_busy: + pm_runtime_put(chan->chip->dev); + return ret; } static void dma_chan_free_chan_resources(struct dma_chan *dchan) -- 2.40.0