spi: fsi: Fix spurious timeout

The driver may return a timeout error even if the status register
indicates that the transfer may proceed. Fix this by restructuring
the polling loop.

Fixes: 89b35e3 ("spi: fsi: Implement a timeout for polling status")
Signed-off-by: Eddie James <eajames@linux.ibm.com>
Link: https://lore.kernel.org/r/20220525165852.33167-2-eajames@linux.ibm.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: Eddie James

drivers/spi/spi-fsi.c

@@ -319,12 +319,12 @@ static int fsi_spi_transfer_data(struct fsi_spi *ctx,
 
 			end = jiffies + msecs_to_jiffies(SPI_FSI_STATUS_TIMEOUT_MS);
 			do {
+				if (time_after(jiffies, end))
+					return -ETIMEDOUT;
+
 				rc = fsi_spi_status(ctx, &status, "TX");
 				if (rc)
 					return rc;
-
-				if (time_after(jiffies, end))
-					return -ETIMEDOUT;
 			} while (status & SPI_FSI_STATUS_TDR_FULL);
 
 			sent += nb;
@@ -337,12 +337,12 @@ static int fsi_spi_transfer_data(struct fsi_spi *ctx,
 		while (transfer->len > recv) {
 			end = jiffies + msecs_to_jiffies(SPI_FSI_STATUS_TIMEOUT_MS);
 			do {
+				if (time_after(jiffies, end))
+					return -ETIMEDOUT;
+
 				rc = fsi_spi_status(ctx, &status, "RX");
 				if (rc)
 					return rc;
-
-				if (time_after(jiffies, end))
-					return -ETIMEDOUT;
 			} while (!(status & SPI_FSI_STATUS_RDR_FULL));
 
 			rc = fsi_spi_read_reg(ctx, SPI_FSI_DATA_RX, &in);