spi: tegra210-quad: Refactor error handling into helper functions

Extract common cleanup code into dedicated helper functions to simplify
the code and improve readability. This refactoring includes:

- tegra_qspi_reset(): Device reset and interrupt cleanup
- tegra_qspi_dma_stop(): DMA termination and disable
- tegra_qspi_pio_stop(): PIO mode disable

No functional changes. This is purely a code reorganization to prepare
for improved timeout handling in subsequent patches.

Signed-off-by: Vishwaroop A <va@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://patch.msgid.link/20251028155703.4151791-3-va@nvidia.com
Signed-off-by: Mark Brown <broonie@kernel.org>
(cherry picked from commit 6022eac)
Signed-off-by: Carol L Soto <csoto@nvidia.com>
Acked-by: Matthew R. Ochs <mochs@nvidia.com>
Acked-by: Jamie Nguyen <jamien@nvidia.com>
Signed-off-by: Jamie Nguyen <jamien@nvidia.com>

Author: Vishwaroop A

drivers/spi/spi-tegra210-quad.c

@@ -1019,17 +1019,22 @@ static void tegra_qspi_dump_regs(struct tegra_qspi *tqspi)
 		tegra_qspi_readl(tqspi, QSPI_FIFO_STATUS));
 }
 
-static void tegra_qspi_handle_error(struct tegra_qspi *tqspi)
+static void tegra_qspi_reset(struct tegra_qspi *tqspi)
 {
-	dev_err(tqspi->dev, "error in transfer, fifo status 0x%08x\n", tqspi->status_reg);
-	tegra_qspi_dump_regs(tqspi);
-	tegra_qspi_flush_fifos(tqspi, true);
 	if (device_reset(tqspi->dev) < 0) {
 		dev_warn_once(tqspi->dev, "device reset failed\n");
 		tegra_qspi_mask_clear_irq(tqspi);
 	}
 }
 
+static void tegra_qspi_handle_error(struct tegra_qspi *tqspi)
+{
+	dev_err(tqspi->dev, "error in transfer, fifo status 0x%08x\n", tqspi->status_reg);
+	tegra_qspi_dump_regs(tqspi);
+	tegra_qspi_flush_fifos(tqspi, true);
+	tegra_qspi_reset(tqspi);
+}
+
 static void tegra_qspi_transfer_end(struct spi_device *spi)
 {
 	struct tegra_qspi *tqspi = spi_controller_get_devdata(spi->controller);
@@ -1074,14 +1079,38 @@ static u32 tegra_qspi_addr_config(bool is_ddr, u8 bus_width, u8 len)
 	return addr_config;
 }
 
+static void tegra_qspi_dma_stop(struct tegra_qspi *tqspi)
+{
+	u32 value;
+
+	if ((tqspi->cur_direction & DATA_DIR_TX) && tqspi->tx_dma_chan)
+		dmaengine_terminate_all(tqspi->tx_dma_chan);
+
+	if ((tqspi->cur_direction & DATA_DIR_RX) && tqspi->rx_dma_chan)
+		dmaengine_terminate_all(tqspi->rx_dma_chan);
+
+	value = tegra_qspi_readl(tqspi, QSPI_DMA_CTL);
+	value &= ~QSPI_DMA_EN;
+	tegra_qspi_writel(tqspi, value, QSPI_DMA_CTL);
+}
+
+static void tegra_qspi_pio_stop(struct tegra_qspi *tqspi)
+{
+	u32 value;
+
+	value = tegra_qspi_readl(tqspi, QSPI_COMMAND1);
+	value &= ~QSPI_PIO;
+	tegra_qspi_writel(tqspi, value, QSPI_COMMAND1);
+}
+
 static int tegra_qspi_combined_seq_xfer(struct tegra_qspi *tqspi,
 					struct spi_message *msg)
 {
 	bool is_first_msg = true;
 	struct spi_transfer *xfer;
 	struct spi_device *spi = msg->spi;
 	u8 transfer_phase = 0;
-	u32 cmd1 = 0, dma_ctl = 0;
+	u32 cmd1 = 0;
 	int ret = 0;
 	u32 address_value = 0;
 	u32 cmd_config = 0, addr_config = 0;
@@ -1150,39 +1179,16 @@ static int tegra_qspi_combined_seq_xfer(struct tegra_qspi *tqspi,
 			if (WARN_ON_ONCE(ret == 0)) {
 				dev_err_ratelimited(tqspi->dev,
 						    "QSPI Transfer failed with timeout\n");
-				if (tqspi->is_curr_dma_xfer) {
-					if ((tqspi->cur_direction & DATA_DIR_TX) &&
-					    tqspi->tx_dma_chan)
-						dmaengine_terminate_all(tqspi->tx_dma_chan);
-					if ((tqspi->cur_direction & DATA_DIR_RX) &&
-					    tqspi->rx_dma_chan)
-						dmaengine_terminate_all(tqspi->rx_dma_chan);
-				}
 
 				/* Abort transfer by resetting pio/dma bit */
-				if (!tqspi->is_curr_dma_xfer) {
-					cmd1 = tegra_qspi_readl
-							(tqspi,
-							 QSPI_COMMAND1);
-					cmd1 &= ~QSPI_PIO;
-					tegra_qspi_writel
-							(tqspi, cmd1,
-							 QSPI_COMMAND1);
-				} else {
-					dma_ctl = tegra_qspi_readl
-							(tqspi,
-							 QSPI_DMA_CTL);
-					dma_ctl &= ~QSPI_DMA_EN;
-					tegra_qspi_writel(tqspi, dma_ctl,
-							  QSPI_DMA_CTL);
-				}
+				if (tqspi->is_curr_dma_xfer)
+					tegra_qspi_dma_stop(tqspi);
+				else
+					tegra_qspi_pio_stop(tqspi);
 
 				/* Reset controller if timeout happens */
-				if (device_reset(tqspi->dev) < 0) {
-					dev_warn_once(tqspi->dev,
-						      "device reset failed\n");
-					tegra_qspi_mask_clear_irq(tqspi);
-				}
+				tegra_qspi_reset(tqspi);
+
 				ret = -EIO;
 				goto exit;
 			}
@@ -1276,12 +1282,10 @@ static int tegra_qspi_non_combined_seq_xfer(struct tegra_qspi *tqspi,
 						  QSPI_DMA_TIMEOUT);
 		if (WARN_ON(ret == 0)) {
 			dev_err(tqspi->dev, "transfer timeout\n");
-			if (tqspi->is_curr_dma_xfer) {
-				if ((tqspi->cur_direction & DATA_DIR_TX) && tqspi->tx_dma_chan)
-					dmaengine_terminate_all(tqspi->tx_dma_chan);
-				if ((tqspi->cur_direction & DATA_DIR_RX) && tqspi->rx_dma_chan)
-					dmaengine_terminate_all(tqspi->rx_dma_chan);
-			}
+
+			if (tqspi->is_curr_dma_xfer)
+				tegra_qspi_dma_stop(tqspi);
+
 			tegra_qspi_handle_error(tqspi);
 			ret = -EIO;
 			goto complete_xfer;