[PATCH v4 5/9] can: m_can: Support pinctrl wakeup state

[Markus Schneider-Pargmann]

am62 requires a wakeup flag being set in pinctrl when mcan pins acts as
a wakeup source. Add support to select the wakeup state if WOL is
enabled.

Signed-off-by: Markus Schneider-Pargmann <msp@xxxxxxxxxxxx>
---
 drivers/net/can/m_can/m_can.c | 68 +++++++++++++++++++++++++++++++++++++++++++
 drivers/net/can/m_can/m_can.h |  4 +++
 2 files changed, 72 insertions(+)

diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c
index 5a4e0ad07e9ecc82de5f1f606707f3380d3679fc..c539375005f71c88fd1f7d1a885ce890ce0e9327 100644
--- a/drivers/net/can/m_can/m_can.c
+++ b/drivers/net/can/m_can/m_can.c
@@ -2196,6 +2196,7 @@ static void m_can_get_wol(struct net_device *dev, struct ethtool_wolinfo *wol)
 static int m_can_set_wol(struct net_device *dev, struct ethtool_wolinfo *wol)
 {
 	struct m_can_classdev *cdev = netdev_priv(dev);
+	struct pinctrl_state *new_pinctrl_state = NULL;
 	bool wol_enable = !!(wol->wolopts & WAKE_PHY);
 	int ret;
 
@@ -2212,7 +2213,28 @@ static int m_can_set_wol(struct net_device *dev, struct ethtool_wolinfo *wol)
 		return ret;
 	}
 
+	if (wol_enable)
+		new_pinctrl_state = cdev->pinctrl_state_wakeup;
+	else
+		new_pinctrl_state = cdev->pinctrl_state_default;
+
+	if (IS_ERR_OR_NULL(new_pinctrl_state))
+		return 0;
+
+	ret = pinctrl_select_state(cdev->pinctrl, new_pinctrl_state);
+	if (ret) {
+		netdev_err(cdev->net, "Failed to select pinctrl state %pE\n",
+			   ERR_PTR(ret));
+		goto err_wakeup_enable;
+	}
+
 	return 0;
+
+err_wakeup_enable:
+	/* Revert wakeup enable */
+	device_set_wakeup_enable(cdev->dev, !wol_enable);
+
+	return ret;
 }
 
 static const struct ethtool_ops m_can_ethtool_ops_coalescing = {
@@ -2340,6 +2362,44 @@ int m_can_class_get_clocks(struct m_can_classdev *cdev)
 }
 EXPORT_SYMBOL_GPL(m_can_class_get_clocks);
 
+static int m_can_class_setup_optional_pinctrl(struct m_can_classdev *class_dev)
+{
+	struct device *dev = class_dev->dev;
+	int ret;
+
+	class_dev->pinctrl = devm_pinctrl_get(dev);
+	if (IS_ERR(class_dev->pinctrl)) {
+		ret = PTR_ERR(class_dev->pinctrl);
+		class_dev->pinctrl = NULL;
+
+		if (ret == -ENODEV)
+			return 0;
+
+		return dev_err_probe(dev, ret, "Failed to get pinctrl\n");
+	}
+
+	class_dev->pinctrl_state_wakeup =
+		pinctrl_lookup_state(class_dev->pinctrl, "wakeup");
+	if (IS_ERR(class_dev->pinctrl_state_wakeup)) {
+		ret = PTR_ERR(class_dev->pinctrl_state_wakeup);
+		class_dev->pinctrl_state_wakeup = NULL;
+
+		if (ret == -ENODEV)
+			return 0;
+
+		return dev_err_probe(dev, ret, "Failed to lookup pinctrl wakeup state\n");
+	}
+
+	class_dev->pinctrl_state_default =
+		pinctrl_lookup_state(class_dev->pinctrl, "default");
+	if (IS_ERR(class_dev->pinctrl_state_default)) {
+		ret = PTR_ERR(class_dev->pinctrl_state_default);
+		return dev_err_probe(dev, ret, "Failed to lookup pinctrl default state\n");
+	}
+
+	return 0;
+}
+
 struct m_can_classdev *m_can_class_allocate_dev(struct device *dev,
 						int sizeof_priv)
 {
@@ -2380,7 +2440,15 @@ struct m_can_classdev *m_can_class_allocate_dev(struct device *dev,
 
 	m_can_of_parse_mram(class_dev, mram_config_vals);
 
+	ret = m_can_class_setup_optional_pinctrl(class_dev);
+	if (ret)
+		goto err_free_candev;
+
 	return class_dev;
+
+err_free_candev:
+	free_candev(net_dev);
+	return ERR_PTR(ret);
 }
 EXPORT_SYMBOL_GPL(m_can_class_allocate_dev);
 
diff --git a/drivers/net/can/m_can/m_can.h b/drivers/net/can/m_can/m_can.h
index 92b2bd8628e6b31370f4accbc2e28f3b2257a71d..b75b0dd6ccc93973d0891daac07c92b61f81dc2a 100644
--- a/drivers/net/can/m_can/m_can.h
+++ b/drivers/net/can/m_can/m_can.h
@@ -126,6 +126,10 @@ struct m_can_classdev {
 	struct mram_cfg mcfg[MRAM_CFG_NUM];
 
 	struct hrtimer hrtimer;
+
+	struct pinctrl *pinctrl;
+	struct pinctrl_state *pinctrl_state_default;
+	struct pinctrl_state *pinctrl_state_wakeup;
 };
 
 struct m_can_classdev *m_can_class_allocate_dev(struct device *dev, int sizeof_priv);

-- 
2.45.2