From: Niklas Söderlund Date: Mon, 15 May 2017 23:09:16 +0000 (+0200) Subject: dmaengine: rcar-dmac: implement device_synchronize() X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=30c45005a46bf55ba52086da5e090ec5a2f1c949;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git dmaengine: rcar-dmac: implement device_synchronize() Implement the device_synchronize() callback which wait until a dma channel is stopped to provide a synchronization point. This protects the driver from multiple race conditions when terminating and freeing resources. E.g. the completion callback still running after device_terminate_all() has completed. Signed-off-by: Niklas Söderlund Signed-off-by: Vinod Koul --- diff --git a/drivers/dma/sh/rcar-dmac.c b/drivers/dma/sh/rcar-dmac.c index c68c3336bdad..fb07cd5fe77b 100644 --- a/drivers/dma/sh/rcar-dmac.c +++ b/drivers/dma/sh/rcar-dmac.c @@ -1365,6 +1365,13 @@ done: spin_unlock_irqrestore(&rchan->lock, flags); } +static void rcar_dmac_device_synchronize(struct dma_chan *chan) +{ + struct rcar_dmac_chan *rchan = to_rcar_dmac_chan(chan); + + synchronize_irq(rchan->irq); +} + /* ----------------------------------------------------------------------------- * IRQ handling */ @@ -1846,6 +1853,7 @@ static int rcar_dmac_probe(struct platform_device *pdev) engine->device_terminate_all = rcar_dmac_chan_terminate_all; engine->device_tx_status = rcar_dmac_tx_status; engine->device_issue_pending = rcar_dmac_issue_pending; + engine->device_synchronize = rcar_dmac_device_synchronize; ret = dma_async_device_register(engine); if (ret < 0)