Merge tag 'linux-can-fixes-for-6.16-20250715' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can

Marc Kleine-Budde says:

====================
pull-request: can 2025-07-15

Brett Werling's patch for the tcan4x5x glue code driver fixes the
detection of chips which are held in reset/sleep and must be woken up
by GPIO prior to communication.

* tag 'linux-can-fixes-for-6.16-20250715' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can:
  can: tcan4x5x: fix reset gpio usage during probe
====================

Link: https://patch.msgid.link/20250715101625.3202690-1-mkl@pengutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 41 insertions, 20 deletions

diff --git a/drivers/net/can/m_can/tcan4x5x-core.c b/drivers/net/can/m_can/tcan4x5x-core.c
index 8edaa339d590..39b0b5277b11 100644
--- a/drivers/net/can/m_can/tcan4x5x-core.c
+++ b/drivers/net/can/m_can/tcan4x5x-core.c
@@ -343,21 +343,19 @@ static void tcan4x5x_get_dt_data(struct m_can_classdev *cdev)
 		of_property_read_bool(cdev->dev->of_node, "ti,nwkrq-voltage-vio");
 }
 
-static int tcan4x5x_get_gpios(struct m_can_classdev *cdev,
-			      const struct tcan4x5x_version_info *version_info)
+static int tcan4x5x_get_gpios(struct m_can_classdev *cdev)
 {
 	struct tcan4x5x_priv *tcan4x5x = cdev_to_priv(cdev);
 	int ret;
 
-	if (version_info->has_wake_pin) {
-		tcan4x5x->device_wake_gpio = devm_gpiod_get(cdev->dev, "device-wake",
-							    GPIOD_OUT_HIGH);
-		if (IS_ERR(tcan4x5x->device_wake_gpio)) {
-			if (PTR_ERR(tcan4x5x->device_wake_gpio) == -EPROBE_DEFER)
-				return -EPROBE_DEFER;
+	tcan4x5x->device_wake_gpio = devm_gpiod_get_optional(cdev->dev,
+							     "device-wake",
+							     GPIOD_OUT_HIGH);
+	if (IS_ERR(tcan4x5x->device_wake_gpio)) {
+		if (PTR_ERR(tcan4x5x->device_wake_gpio) == -EPROBE_DEFER)
+			return -EPROBE_DEFER;
 
-			tcan4x5x_disable_wake(cdev);
-		}
+		tcan4x5x->device_wake_gpio = NULL;
 	}
 
 	tcan4x5x->reset_gpio = devm_gpiod_get_optional(cdev->dev, "reset",
@@ -369,14 +367,31 @@ static int tcan4x5x_get_gpios(struct m_can_classdev *cdev,
 	if (ret)
 		return ret;
 
-	if (version_info->has_state_pin) {
-		tcan4x5x->device_state_gpio = devm_gpiod_get_optional(cdev->dev,
-								      "device-state",
-								      GPIOD_IN);
-		if (IS_ERR(tcan4x5x->device_state_gpio)) {
-			tcan4x5x->device_state_gpio = NULL;
-			tcan4x5x_disable_state(cdev);
-		}
+	tcan4x5x->device_state_gpio = devm_gpiod_get_optional(cdev->dev,
+							      "device-state",
+							      GPIOD_IN);
+	if (IS_ERR(tcan4x5x->device_state_gpio))
+		tcan4x5x->device_state_gpio = NULL;
+
+	return 0;
+}
+
+static int tcan4x5x_check_gpios(struct m_can_classdev *cdev,
+				const struct tcan4x5x_version_info *version_info)
+{
+	struct tcan4x5x_priv *tcan4x5x = cdev_to_priv(cdev);
+	int ret;
+
+	if (version_info->has_wake_pin && !tcan4x5x->device_wake_gpio) {
+		ret = tcan4x5x_disable_wake(cdev);
+		if (ret)
+			return ret;
+	}
+
+	if (version_info->has_state_pin && !tcan4x5x->device_state_gpio) {
+		ret = tcan4x5x_disable_state(cdev);
+		if (ret)
+			return ret;
 	}
 
 	return 0;
@@ -468,15 +483,21 @@ static int tcan4x5x_can_probe(struct spi_device *spi)
 		goto out_m_can_class_free_dev;
 	}
 
+	ret = tcan4x5x_get_gpios(mcan_class);
+	if (ret) {
+		dev_err(&spi->dev, "Getting gpios failed %pe\n", ERR_PTR(ret));
+		goto out_power;
+	}
+
 	version_info = tcan4x5x_find_version(priv);
 	if (IS_ERR(version_info)) {
 		ret = PTR_ERR(version_info);
 		goto out_power;
 	}
 
-	ret = tcan4x5x_get_gpios(mcan_class, version_info);
+	ret = tcan4x5x_check_gpios(mcan_class, version_info);
 	if (ret) {
-		dev_err(&spi->dev, "Getting gpios failed %pe\n", ERR_PTR(ret));
+		dev_err(&spi->dev, "Checking gpios failed %pe\n", ERR_PTR(ret));
 		goto out_power;
 	}