spi: sprd: Release DMA channel also on probe deferral

If dma_request_chan() for TX channel fails with EPROBE_DEFER, the RX
channel would not be released and on next re-probe it would be requested
second time.

Fixes: 386119bc7b ("spi: sprd: spi: sprd: Add DMA mode support")
Cc: <stable@vger.kernel.org>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Chunyan Zhang <zhang.lyra@gmail.com>
Link: https://lore.kernel.org/r/20200901152713.18629-1-krzk@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-sprd.c

@@ -563,11 +563,11 @@ static int sprd_spi_dma_request(struct sprd_spi *ss)
 
 	ss->dma.dma_chan[SPRD_SPI_TX]  = dma_request_chan(ss->dev, "tx_chn");
 	if (IS_ERR_OR_NULL(ss->dma.dma_chan[SPRD_SPI_TX])) {
+		dma_release_channel(ss->dma.dma_chan[SPRD_SPI_RX]);
 		if (PTR_ERR(ss->dma.dma_chan[SPRD_SPI_TX]) == -EPROBE_DEFER)
 			return PTR_ERR(ss->dma.dma_chan[SPRD_SPI_TX]);
 
 		dev_err(ss->dev, "request TX DMA channel failed!\n");
-		dma_release_channel(ss->dma.dma_chan[SPRD_SPI_RX]);
 		return PTR_ERR(ss->dma.dma_chan[SPRD_SPI_TX]);
 	}