spi: stm32-ospi: avoid false timeout expiration

In case of stress test, timeout could occurred. To avoid false timeout,
check that the transfer is completed or not.

Change-Id: I6684b67faf77d9ea148838c488a979d69b3a16aa
Signed-off-by: Christophe Kerello <christophe.kerello@foss.st.com>
Reviewed-on: https://gerrit.st.com/c/mpu/oe/st/linux-stm32/+/400728
ACI: CITOOLS <MDG-smet-aci-reviews@list.st.com>
Tested-by: Jerome BESNARD <jerome.besnard@st.com>
Tested-by: Christophe KERELLO <christophe.kerello@st.com>
Domain-Review: Christophe KERELLO <christophe.kerello@st.com>
Reviewed-by: Christophe KERELLO <christophe.kerello@st.com>
ACI: CIBUILD <MDG-smet-aci-builds@list.st.com>

Author: Christophe Kerello

drivers/spi/spi-stm32-ospi.c

@@ -200,8 +200,13 @@ static int stm32_ospi_wait_poll_status(struct stm32_ospi *ospi,
 	writel_relaxed(cr | CR_SMIE, regs_base + OSPI_CR);
 
 	if (!wait_for_completion_timeout(&omi->match_completion,
-					 msecs_to_jiffies(ospi->status_timeout)))
-		return -ETIMEDOUT;
+					 msecs_to_jiffies(ospi->status_timeout))) {
+		u32 sr = readl_relaxed(regs_base + OSPI_SR);
+
+		/* Avoid false timeout */
+		if (!(sr & SR_SMF))
+			return -ETIMEDOUT;
+	}
 
 	writel_relaxed(FCR_CSMF, regs_base + OSPI_FCR);