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dmaengine dw: Revert "dmaengine: dw: Enable runtime PM"

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This reverts commit 842067940a.
For some solutions e.g. sound/soc/intel/catpt, DW DMA is part of a
compound device (in that very example, domains: ADSP, SSP0, SSP1, DMA0
and DMA1 are part of a single entity) rather than being a standalone
one. Driver for said device may enlist DMA to transfer data during
suspend or resume sequences.

Manipulating RPM explicitly in dw's DMA request and release channel
functions causes suspend() to also invoke resume() for the exact same
device. Similar situation occurs for resume() sequence. Effectively
renders device dysfunctional after first suspend() attempt. Revert the
change to address the problem.

Fixes: 842067940a ("dmaengine: dw: Enable runtime PM")
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Cezary Rojewski <cezary.rojewski@intel.com>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20210203191924.15706-1-cezary.rojewski@intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
This commit is contained in:
Cezary Rojewski 2021-02-03 20:19:24 +01:00 committed by Vinod Koul
parent 89e3becd8f
commit b6c14d7a83
1 changed files with 0 additions and 6 deletions
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6
drivers/dma/dw/core.c
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@ -982,11 +982,8 @@ 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;
}
@ -1003,7 +1000,6 @@ 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;
}
@ -1047,8 +1043,6 @@ 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__);
}