The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 25962e1a7f1d522f1b57ead2f266fab570042a70 Mon Sep 17 00:00:00 2001

From: Frieder Schrempf frieder.schrempf@kontron.de Date: Tue, 25 Feb 2020 08:23:20 +0000 Subject: [PATCH] dmaengine: imx-sdma: Fix the event id check to include RX event for UART6

On i.MX6UL/ULL and i.MX6SX the DMA event id for the RX channel of UART6 is '0'. To fix the broken DMA support for UART6, we change the check for event_id0 to include '0' as a valid id.

Fixes: 1ec1e82f2510 ("dmaengine: Add Freescale i.MX SDMA support") Signed-off-by: Frieder Schrempf frieder.schrempf@kontron.de Reviewed-by: Fabio Estevam festevam@gmail.com Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200225082139.7646-1-frieder.schrempf@kontron.de Signed-off-by: Vinod Koul vkoul@kernel.org

diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c index 332ca5034504..4d4477df4ede 100644 --- a/drivers/dma/imx-sdma.c +++ b/drivers/dma/imx-sdma.c @@ -1331,7 +1331,7 @@ static void sdma_free_chan_resources(struct dma_chan *chan)

sdma_channel_synchronize(chan);

- if (sdmac->event_id0) + if (sdmac->event_id0 >= 0) sdma_event_disable(sdmac, sdmac->event_id0); if (sdmac->event_id1) sdma_event_disable(sdmac, sdmac->event_id1); @@ -1632,7 +1632,7 @@ static int sdma_config(struct dma_chan *chan, memcpy(&sdmac->slave_config, dmaengine_cfg, sizeof(*dmaengine_cfg));

/* Set ENBLn earlier to make sure dma request triggered after that */ - if (sdmac->event_id0) { + if (sdmac->event_id0 >= 0) { if (sdmac->event_id0 >= sdmac->sdma->drvdata->num_events) return -EINVAL; sdma_event_enable(sdmac, sdmac->event_id0);