It's a good idea to reset a ip-block/spi device before using it, this
patch will reset the device.
Added a generic reset function if needed elsewhere.
Signed-off-by: Sean Nyekjaer <sean@xxxxxxxxxx>
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
---
Changes v3:
- added reset if the reset_gpio is not avaliable
drivers/net/can/m_can/tcan4x5x.c | 19 +++++++++++++++++--
1 file changed, 17 insertions(+), 2 deletions(-)
diff --git a/drivers/net/can/m_can/tcan4x5x.c b/drivers/net/can/m_can/tcan4x5x.c
index b6b2feca9e8f..960a16aca7ca 100644
--- a/drivers/net/can/m_can/tcan4x5x.c
+++ b/drivers/net/can/m_can/tcan4x5x.c
@@ -166,6 +166,21 @@ static void tcan4x5x_check_wake(struct tcan4x5x_priv *priv)
}
}
+static void tcan4x5x_reset(struct tcan4x5x_priv *priv)
+{
+ if (priv->reset_gpio) {
+ gpiod_set_value(priv->reset_gpio, 1);
+
+ /* tpulse_width minimum 30us */
+ usleep_range(30, 100);
+ gpiod_set_value(priv->reset_gpio, 0);
+ } else {
+ regmap_write(priv->regmap, TCAN4X5X_CONFIG, TCAN4X5X_SW_RESET);
+ }
+
+ usleep_range(700, 1000);
+}
+
static int regmap_spi_gather_write(void *context, const void *reg,
size_t reg_len, const void *val,
size_t val_len)
@@ -365,8 +380,8 @@ static int tcan4x5x_parse_config(struct m_can_classdev *cdev)
GPIOD_OUT_LOW);
if (IS_ERR(tcan4x5x->reset_gpio))
tcan4x5x->reset_gpio = NULL;
-
- usleep_range(700, 1000);
+ else
+ tcan4x5x_reset(tcan4x5x);
tcan4x5x->device_state_gpio = devm_gpiod_get_optional(cdev->dev,
"device-state",
--
2.24.0
