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Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ] > > pm_runtime_get_sync() leaves the IMG MDC device's usage counter > incremented when runtime resume fails. mdc_alloc_chan_resources() returns > that error to the DMA core, so the channel's client count is not > incremented and mdc_free_chan_resources() is not called to drop the > reference. Repeated allocation attempts can therefore accumulate usage > references and prevent runtime suspend. > > Use pm_runtime_resume_and_get() so a failed resume does not retain a > usage reference while successful allocations remain paired with > mdc_free_chan_resources(). DMA core only treats negative return values as > allocation failures, so the helper's zero success return preserves > behavior. > > This issue was found by a static analysis checker and confirmed by manual > source review. > > Fixes: 56d355e6f586 ("dmaengine: img-mdc: Add runtime PM") > Signed-off-by: Ruoyu Wang > --- Reviewed-by: Frank Li > drivers/dma/img-mdc-dma.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/dma/img-mdc-dma.c b/drivers/dma/img-mdc-dma.c > index b3765ba1580308..a3192d49b6c860 100644 > --- a/drivers/dma/img-mdc-dma.c > +++ b/drivers/dma/img-mdc-dma.c > @@ -738,7 +738,7 @@ static int mdc_alloc_chan_resources(struct dma_chan *chan) > struct mdc_chan *mchan = to_mdc_chan(chan); > struct device *dev = mdma2dev(mchan->mdma); > > - return pm_runtime_get_sync(dev); > + return pm_runtime_resume_and_get(dev); > } > > static void mdc_free_chan_resources(struct dma_chan *chan) > -- > 2.51.0 >