net: dsa: qca8k: add support for switch rev

qca8k internal phy driver require some special debug value to be set
based on the switch revision. Rework the switch id read function to
also read the chip revision.

Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 34 insertions, 19 deletions

diff --git a/drivers/net/dsa/qca8k.c b/drivers/net/dsa/qca8k.c
index 10e3e1ca7e95..35ff4cf08786 100644
--- a/drivers/net/dsa/qca8k.c
+++ b/drivers/net/dsa/qca8k.c
@@ -1579,12 +1579,40 @@ static const struct dsa_switch_ops qca8k_switch_ops = {
 	.phylink_mac_link_up	= qca8k_phylink_mac_link_up,
 };
 
+static int qca8k_read_switch_id(struct qca8k_priv *priv)
+{
+	const struct qca8k_match_data *data;
+	u32 val;
+	u8 id;
+
+	/* get the switches ID from the compatible */
+	data = of_device_get_match_data(priv->dev);
+	if (!data)
+		return -ENODEV;
+
+	val = qca8k_read(priv, QCA8K_REG_MASK_CTRL);
+	if (val < 0)
+		return -ENODEV;
+
+	id = QCA8K_MASK_CTRL_DEVICE_ID(val & QCA8K_MASK_CTRL_DEVICE_ID_MASK);
+	if (id != data->id) {
+		dev_err(priv->dev, "Switch id detected %x but expected %x", id, data->id);
+		return -ENODEV;
+	}
+
+	priv->switch_id = id;
+
+	/* Save revision to communicate to the internal PHY driver */
+	priv->switch_revision = (val & QCA8K_MASK_CTRL_REV_ID_MASK);
+
+	return 0;
+}
+
 static int
 qca8k_sw_probe(struct mdio_device *mdiodev)
 {
-	const struct qca8k_match_data *data;
 	struct qca8k_priv *priv;
-	u32 id;
+	int ret;
 
 	/* allocate the private data struct so that we can probe the switches
 	 * ID register
@@ -1610,24 +1638,11 @@ qca8k_sw_probe(struct mdio_device *mdiodev)
 		gpiod_set_value_cansleep(priv->reset_gpio, 0);
 	}
 
-	/* get the switches ID from the compatible */
-	data = of_device_get_match_data(&mdiodev->dev);
-	if (!data)
-		return -ENODEV;
-
-	/* read the switches ID register */
-	id = qca8k_read(priv, QCA8K_REG_MASK_CTRL);
-	if (id < 0)
-		return id;
-
-	id >>= QCA8K_MASK_CTRL_ID_S;
-	id &= QCA8K_MASK_CTRL_ID_M;
-	if (id != data->id) {
-		dev_err(&mdiodev->dev, "Switch id detected %x but expected %x", id, data->id);
-		return -ENODEV;
-	}
+	/* Check the detected switch id */
+	ret = qca8k_read_switch_id(priv);
+	if (ret)
+		return ret;
 
-	priv->switch_id = id;
 	priv->ds = devm_kzalloc(&mdiodev->dev, sizeof(*priv->ds), GFP_KERNEL);
 	if (!priv->ds)
 		return -ENOMEM;