spi: sprd: adi: Add a reset reason for watchdog mode

When the system was rebooted by watchdog, now we did not save the watchdog
reset mode which will make system enter a incorrect mode after rebooting.

Thus we should set the watchdog reset mode as default when opening the
watchdog configuration, that means if the system was rebooted by other
reason through the restart_handler(), then we will clear the default
watchdog reset mode to save the correct reset mode.
Signed-off-by: Sherry Zong <sherry.zong@unisoc.com>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Link: https://lore.kernel.org/r/1563f3de43c6c2262d597a25d6138b5de61ea23d.1564125131.git.baolin.wang@linaro.orgSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-sprd-adi.c

@@ -99,6 +99,7 @@
 #define HWRST_STATUS_IQMODE		0xb0
 #define HWRST_STATUS_SPRDISK		0xc0
 #define HWRST_STATUS_FACTORYTEST	0xe0
+#define HWRST_STATUS_WATCHDOG		0xf0
 
 /* Use default timeout 50 ms that converts to watchdog values */
 #define WDG_LOAD_VAL			((50 * 1000) / 32768)
@@ -309,6 +310,18 @@ static int sprd_adi_transfer_one(struct spi_controller *ctlr,
 	return 0;
 }
 
+static void sprd_adi_set_wdt_rst_mode(struct sprd_adi *sadi)
+{
+#ifdef CONFIG_SPRD_WATCHDOG
+	u32 val;
+
+	/* Set default watchdog reboot mode */
+	sprd_adi_read(sadi, sadi->slave_pbase + PMIC_RST_STATUS, &val);
+	val |= HWRST_STATUS_WATCHDOG;
+	sprd_adi_write(sadi, sadi->slave_pbase + PMIC_RST_STATUS, val);
+#endif
+}
+
 static int sprd_adi_restart_handler(struct notifier_block *this,
 				    unsigned long mode, void *cmd)
 {
@@ -347,6 +360,7 @@ static int sprd_adi_restart_handler(struct notifier_block *this,
 
 	/* Record the reboot mode */
 	sprd_adi_read(sadi, sadi->slave_pbase + PMIC_RST_STATUS, &val);
+	val &= ~HWRST_STATUS_WATCHDOG;
 	val |= reboot_mode;
 	sprd_adi_write(sadi, sadi->slave_pbase + PMIC_RST_STATUS, val);
 
@@ -475,6 +489,7 @@ static int sprd_adi_probe(struct platform_device *pdev)
 	}
 
 	sprd_adi_hw_init(sadi);
+	sprd_adi_set_wdt_rst_mode(sadi);
 
 	ctlr->dev.of_node = pdev->dev.of_node;
 	ctlr->bus_num = pdev->id;