[PATCH] drivers: spi: Fix data loss issue in QSPI

[Naresh Kumar Ravulapalli]

QSPI driver performs chip select operation before every read/write
access. During this operation, driver needs to enable and disable
the QSPI controller. This may cause data loss if there is inadvertent
halting of any ongoing read/write operation. To avoid this scenario,
waiting for the QSPI status to be idle before next read/write
operation is implemented.

Signed-off-by: Naresh Kumar Ravulapalli <nareshkumar.ravulapalli at altera.com>
---
 drivers/spi/cadence_qspi_apb.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/spi/cadence_qspi_apb.c b/drivers/spi/cadence_qspi_apb.c
index f2f69cf9f1..b579699d2e 100644
--- a/drivers/spi/cadence_qspi_apb.c
+++ b/drivers/spi/cadence_qspi_apb.c
@@ -747,6 +747,10 @@ cadence_qspi_apb_indirect_read_execute(struct cadence_spi_priv *priv,
 		goto failrd;
 	}
 
+	/* Wait til QSPI is idle */
+	if (!cadence_qspi_wait_idle(priv->regbase))
+		return -EIO;
+
 	return 0;
 
 failrd:
@@ -914,6 +918,11 @@ cadence_qspi_apb_indirect_write_execute(struct cadence_spi_priv *priv,
 
 	if (bounce_buf)
 		free(bounce_buf);
+
+	/* Wait til QSPI is idle */
+	if (!cadence_qspi_wait_idle(priv->regbase))
+		return -EIO;
+
 	return 0;
 
 failwr:
-- 
2.35.3