From 842067940a3e3fc008a60fee388e000219b32632 Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Tue, 3 Nov 2020 20:39:38 +0200 Subject: [PATCH] dmaengine: dw: Enable runtime PM When consumer requests channel power on the DMA controller device and otherwise on the freeing channel resources. Note, in some cases consumer acquires channel at the ->probe() stage and releases it at the ->remove() stage. It will mean that DMA controller device will be powered during all this time if there is no assist from hardware to idle it. The above mentioned cases should be investigated separately and individually. Signed-off-by: Andy Shevchenko Acked-by: Viresh Kumar Link: https://lore.kernel.org/r/20201103183938.64752-1-andriy.shevchenko@linux.intel.com Signed-off-by: Vinod Koul --- drivers/dma/dw/core.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c index 7ab83fe601ed..19a23767533a 100644 --- a/drivers/dma/dw/core.c +++ b/drivers/dma/dw/core.c @@ -982,8 +982,11 @@ static int dwc_alloc_chan_resources(struct dma_chan *chan) dev_vdbg(chan2dev(chan), "%s\n", __func__); + pm_runtime_get_sync(dw->dma.dev); + /* ASSERT: channel is idle */ if (dma_readl(dw, CH_EN) & dwc->mask) { + pm_runtime_put_sync_suspend(dw->dma.dev); dev_dbg(chan2dev(chan), "DMA channel not idle?\n"); return -EIO; } @@ -1000,6 +1003,7 @@ static int dwc_alloc_chan_resources(struct dma_chan *chan) * We need controller-specific data to set up slave transfers. */ if (chan->private && !dw_dma_filter(chan, chan->private)) { + pm_runtime_put_sync_suspend(dw->dma.dev); dev_warn(chan2dev(chan), "Wrong controller-specific data\n"); return -EINVAL; } @@ -1043,6 +1047,8 @@ static void dwc_free_chan_resources(struct dma_chan *chan) if (!dw->in_use) do_dw_dma_off(dw); + pm_runtime_put_sync_suspend(dw->dma.dev); + dev_vdbg(chan2dev(chan), "%s: done\n", __func__); }