[PATCH 5.4 373/434] can: m_can: tcan4x5x: add required delay after reset

From: Greg Kroah-Hartman
Date: Sun Dec 29 2019 - 13:00:34 EST


From: Sean Nyekjaer <sean@xxxxxxxxxx>

commit 60552253e29c8860ee5bf1e6064591b0917c0394 upstream.

According to section "8.3.8 RST Pin" in the datasheet we are required to
wait >700us after the device is reset.

Signed-off-by: Sean Nyekjaer <sean@xxxxxxxxxx>
Acked-by: Dan Murphy <dmurphy@xxxxxx>
Cc: linux-stable <stable@xxxxxxxxxxxxxxx> # >= v5.4
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/net/can/m_can/tcan4x5x.c | 2 ++
1 file changed, 2 insertions(+)

--- a/drivers/net/can/m_can/tcan4x5x.c
+++ b/drivers/net/can/m_can/tcan4x5x.c
@@ -354,6 +354,8 @@ static int tcan4x5x_parse_config(struct
if (IS_ERR(tcan4x5x->reset_gpio))
tcan4x5x->reset_gpio = NULL;

+ usleep_range(700, 1000);
+
tcan4x5x->device_state_gpio = devm_gpiod_get_optional(cdev->dev,
"device-state",
GPIOD_IN);