mtd: rawnand: marvell: Release DMA channel on error

Release the DMA channel on errors after the channel has been successfully
requested.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200227123749.24064-3-peter.ujfalusi@ti.com

drivers/mtd/nand/raw/marvell_nand.c

@@ -2751,8 +2751,10 @@ static int marvell_nfc_init_dma(struct marvell_nfc *nfc)
 	}
 
 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	if (!r)
-		return -ENXIO;
+	if (!r) {
+		ret = -ENXIO;
+		goto release_channel;
+	}
 
 	config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
 	config.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
@@ -2763,7 +2765,7 @@ static int marvell_nfc_init_dma(struct marvell_nfc *nfc)
 	ret = dmaengine_slave_config(nfc->dma_chan, &config);
 	if (ret < 0) {
 		dev_err(nfc->dev, "Failed to configure DMA channel\n");
-		return ret;
+		goto release_channel;
 	}
 
 	/*
@@ -2773,12 +2775,20 @@ static int marvell_nfc_init_dma(struct marvell_nfc *nfc)
 	 * the provided buffer.
 	 */
 	nfc->dma_buf = kmalloc(MAX_CHUNK_SIZE, GFP_KERNEL | GFP_DMA);
-	if (!nfc->dma_buf)
-		return -ENOMEM;
+	if (!nfc->dma_buf) {
+		ret = -ENOMEM;
+		goto release_channel;
+	}
 
 	nfc->use_dma = true;
 
 	return 0;
+
+release_channel:
+	dma_release_channel(nfc->dma_chan);
+	nfc->dma_chan = NULL;
+
+	return ret;
 }
 
 static void marvell_nfc_reset(struct marvell_nfc *nfc)
@@ -2920,10 +2930,13 @@ static int marvell_nfc_probe(struct platform_device *pdev)
 
 	ret = marvell_nand_chips_init(dev, nfc);
 	if (ret)
-		goto unprepare_reg_clk;
+		goto release_dma;
 
 	return 0;
 
+release_dma:
+	if (nfc->use_dma)
+		dma_release_channel(nfc->dma_chan);
 unprepare_reg_clk:
 	clk_disable_unprepare(nfc->reg_clk);
 unprepare_core_clk: