commit e09784728689de7949d4cdd559a9590e0bfcc702
author T Karthik Reddy <t.karthik.reddy@xilinx.com> Fri Jul 15 19:31:17 2022 +0530
committer Michal Simek <michal.simek@amd.com> Tue Jul 26 09:34:21 2022 +0200
tree 7b58c440768c63049f4fa327f30d3104a57c4b49
parent 1acb70393f2719c70d92f52d91be2525fa1db679

spi: zynq_qspi: Use dummy buswidth in dummy byte calculation

Fix dummy bytes calculation incase of valid dummy bytes when dummy
buswidth is > 1. Current dummy bytes calculation does not provide
correct dummy values for dummy buswidth > 1.

Signed-off-by: T Karthik Reddy <t.karthik.reddy@xilinx.com>
Signed-off-by: Ashok Reddy Soma <ashok.reddy.soma@xilinx.com>
Link: https://lore.kernel.org/r/1657893679-20039-3-git-send-email-ashok.reddy.soma@xilinx.com
Signed-off-by: Michal Simek <michal.simek@amd.com>

drivers/spi/zynq_qspi.c

diff --git a/drivers/spi/zynq_qspi.c b/drivers/spi/zynq_qspi.c
index 066a0c6..b138c3c 100644
--- a/drivers/spi/zynq_qspi.c
+++ b/drivers/spi/zynq_qspi.c
@@ -679,6 +679,7 @@
 			     const struct spi_mem_op *op)
 {
 	int op_len, pos = 0, ret, i;
+	u32 dummy_bytes = 0;
 	unsigned int flag = 0;
 	const u8 *tx_buf = NULL;
 	u8 *rx_buf = NULL;
@@ -691,6 +692,11 @@
 	}
 
 	op_len = op->cmd.nbytes + op->addr.nbytes + op->dummy.nbytes;
+	if (op->dummy.nbytes) {
+		op_len = op->cmd.nbytes + op->addr.nbytes +
+			 op->dummy.nbytes / op->dummy.buswidth;
+		dummy_bytes = op->dummy.nbytes / op->dummy.buswidth;
+	}
 
 	u8 op_buf[op_len];
 
@@ -704,8 +710,8 @@
 		pos += op->addr.nbytes;
 	}
 
-	if (op->dummy.nbytes)
-		memset(op_buf + pos, 0xff, op->dummy.nbytes);
+	if (dummy_bytes)
+		memset(op_buf + pos, 0xff, dummy_bytes);
 
 	/* 1st transfer: opcode + address + dummy cycles */
 	/* Make sure to set END bit if no tx or rx data messages follow */