dmaengine: imx-sdma: Fix the event id check to include RX event for UART6

commit 25962e1a7f1d522f1b57ead2f266fab570042a70 upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index 839f610436551549c974ed26400e7d49d4399e54..67736c801f3caa69220030b2f1d2bce9b9c0e9f9 100644 (file)
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -1328,7 +1328,7 @@ 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);
@@ -1629,7 +1629,7 @@ 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);