[PATCH AUTOSEL 5.4 168/350] spi: sprd: adi: Add missing lock protection when rebooting

Sasha Levin
2019-12-10T21:29:00Z

From: Lingling Xu <ling_ling.xu@unisoc.com>

[ Upstream commit 91ea1d70607e374b014b4b9bea771ce661f9f64b ]

When rebooting the system, we should lock the watchdog after
configuration to make sure the watchdog can reboot the system
successfully.

Signed-off-by: Lingling Xu <ling_ling.xu@unisoc.com>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Link: https://lore.kernel.org/r/7b04711127434555e3a1a86bc6be99860cd86668.1572257085.git.baolin.wang@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/spi/spi-sprd-adi.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/spi/spi-sprd-adi.c b/drivers/spi/spi-sprd-adi.c
index 9a051286f1207..9613cfe3c0a25 100644
--- a/drivers/spi/spi-sprd-adi.c
+++ b/drivers/spi/spi-sprd-adi.c
@@ -393,6 +393,9 @@ static int sprd_adi_restart_handler(struct notifier_block *this,
val |= BIT_WDG_RUN | BIT_WDG_RST;
sprd_adi_write(sadi, sadi->slave_pbase + REG_WDG_CTRL, val);

+ /* Lock the watchdog */
+ sprd_adi_write(sadi, sadi->slave_pbase + REG_WDG_LOCK, ~WDG_UNLOCK_KEY);
+
mdelay(1000);

dev_emerg(sadi->dev, "Unable to restart system\n");
--
2.20.1