spi: dw: Get rid of dma_inited flag

This flag is superfluous in all cases where it's being used, i.e.
 * ->can_dma() won't be called without dma_inited == 1
 * DMA ->exit() callback can rely on txchan and rxchan variables

So, get rid of dma_inited flag.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200507115449.8093-2-andriy.shevchenko@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-dw-mid.c

@@ -57,20 +57,21 @@ static int mid_spi_dma_init_mfld(struct device *dev, struct dw_spi *dws)
 	dws->rxchan = dma_request_channel(mask, mid_spi_dma_chan_filter, rx);
 	if (!dws->rxchan)
 		goto err_exit;
-	dws->master->dma_rx = dws->rxchan;
 
 	/* 2. Init tx channel */
 	tx->dma_dev = &dma_dev->dev;
 	dws->txchan = dma_request_channel(mask, mid_spi_dma_chan_filter, tx);
 	if (!dws->txchan)
 		goto free_rxchan;
+
+	dws->master->dma_rx = dws->rxchan;
 	dws->master->dma_tx = dws->txchan;
 
-	dws->dma_inited = 1;
 	return 0;
 
 free_rxchan:
 	dma_release_channel(dws->rxchan);
+	dws->rxchan = NULL;
 err_exit:
 	return -EBUSY;
 }
@@ -80,29 +81,31 @@ static int mid_spi_dma_init_generic(struct device *dev, struct dw_spi *dws)
 	dws->rxchan = dma_request_slave_channel(dev, "rx");
 	if (!dws->rxchan)
 		return -ENODEV;
-	dws->master->dma_rx = dws->rxchan;
 
 	dws->txchan = dma_request_slave_channel(dev, "tx");
 	if (!dws->txchan) {
 		dma_release_channel(dws->rxchan);
+		dws->rxchan = NULL;
 		return -ENODEV;
 	}
+
+	dws->master->dma_rx = dws->rxchan;
 	dws->master->dma_tx = dws->txchan;
 
-	dws->dma_inited = 1;
 	return 0;
 }
 
 static void mid_spi_dma_exit(struct dw_spi *dws)
 {
-	if (!dws->dma_inited)
-		return;
-
-	dmaengine_terminate_sync(dws->txchan);
-	dma_release_channel(dws->txchan);
+	if (dws->txchan) {
+		dmaengine_terminate_sync(dws->txchan);
+		dma_release_channel(dws->txchan);
+	}
 
-	dmaengine_terminate_sync(dws->rxchan);
-	dma_release_channel(dws->rxchan);
+	if (dws->rxchan) {
+		dmaengine_terminate_sync(dws->rxchan);
+		dma_release_channel(dws->rxchan);
+	}
 }
 
 static irqreturn_t dma_transfer(struct dw_spi *dws)
@@ -126,9 +129,6 @@ static bool mid_spi_can_dma(struct spi_controller *master,
 {
 	struct dw_spi *dws = spi_controller_get_devdata(master);
 
-	if (!dws->dma_inited)
-		return false;
-
 	return xfer->len > dws->fifo_len;
 }
 

drivers/spi/spi-dw.c

@@ -470,7 +470,6 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws)
 
 	dws->master = master;
 	dws->type = SSI_MOTO_SPI;
-	dws->dma_inited = 0;
 	dws->dma_addr = (dma_addr_t)(dws->paddr + DW_SPI_DR);
 	spin_lock_init(&dws->buf_lock);
 
@@ -509,7 +508,6 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws)
 		ret = dws->dma_ops->dma_init(dev, dws);
 		if (ret) {
 			dev_warn(dev, "DMA init failed\n");
-			dws->dma_inited = 0;
 		} else {
 			master->can_dma = dws->dma_ops->can_dma;
 		}

drivers/spi/spi-dw.h

@@ -141,7 +141,6 @@ struct dw_spi {
 	u32			current_freq;	/* frequency in hz */
 
 	/* DMA info */
-	int			dma_inited;
 	struct dma_chan		*txchan;
 	struct dma_chan		*rxchan;
 	unsigned long		dma_chan_busy;