spi: zynq_qspi: Read only one byte at a time from txbuf

Read only one byte at a time from txbuf as txbuf may not be
aligned and accessing more than a byte at a time may cause
alignment issues. This fixes the issue of data abort exception
while writing to flash device.

Signed-off-by: Siva Durga Prasad Paladugu <siva.durga.paladugu@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Ashok Reddy Soma <ashok.reddy.soma@xilinx.com>
Link: https://lore.kernel.org/r/20220131052240.23403-3-ashok.reddy.soma@xilinx.com

diff --git a/drivers/spi/zynq_qspi.c b/drivers/spi/zynq_qspi.c
index 34d39d6..aa060d7 100644 (file)
--- a/drivers/spi/zynq_qspi.c
+++ b/drivers/spi/zynq_qspi.c
@@ -276,13 +276,17 @@ static void zynq_qspi_write_data(struct  zynq_qspi_priv *priv,
                        *data |= 0xFFFFFF00;
                        break;
                case 2:
-                       *data = *((u16 *)priv->tx_buf);
-                       priv->tx_buf += 2;
+                       *data = *((u8 *)priv->tx_buf);
+                       priv->tx_buf += 1;
+                       *data |= (*((u8 *)priv->tx_buf) << 8);
+                       priv->tx_buf += 1;
                        *data |= 0xFFFF0000;
                        break;
                case 3:
-                       *data = *((u16 *)priv->tx_buf);
-                       priv->tx_buf += 2;
+                       *data = *((u8 *)priv->tx_buf);
+                       priv->tx_buf += 1;
+                       *data |= (*((u8 *)priv->tx_buf) << 8);
+                       priv->tx_buf += 1;
                        *data |= (*((u8 *)priv->tx_buf) << 16);
                        priv->tx_buf += 1;
                        *data |= 0xFF000000;