net: dsa: qca8k: add support for pws config reg

Some qca8327 switch require to force the ignore of power on sel
strapping. Some switch require to set the led open drain mode in regs
instead of using strapping. While most of the device implements this
using the correct way using pin strapping, there are still some broken
device that require to be set using sw regs.
Introduce a new binding and support these special configuration.
As led open drain require to ignore pin strapping to work, the probe
fails with EINVAL error with incorrect configuration.

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>

drivers/net/dsa/qca8k.c

@@ -931,6 +931,41 @@ static int qca8k_find_cpu_port(struct dsa_switch *ds)
 	return -EINVAL;
 }
 
+static int
+qca8k_setup_of_pws_reg(struct qca8k_priv *priv)
+{
+	struct device_node *node = priv->dev->of_node;
+	u32 val = 0;
+	int ret;
+
+	/* QCA8327 require to set to the correct mode.
+	 * His bigger brother QCA8328 have the 172 pin layout.
+	 * Should be applied by default but we set this just to make sure.
+	 */
+	if (priv->switch_id == QCA8K_ID_QCA8327) {
+		ret = qca8k_rmw(priv, QCA8K_REG_PWS, QCA8327_PWS_PACKAGE148_EN,
+				QCA8327_PWS_PACKAGE148_EN);
+		if (ret)
+			return ret;
+	}
+
+	if (of_property_read_bool(node, "qca,ignore-power-on-sel"))
+		val |= QCA8K_PWS_POWER_ON_SEL;
+
+	if (of_property_read_bool(node, "qca,led-open-drain")) {
+		if (!(val & QCA8K_PWS_POWER_ON_SEL)) {
+			dev_err(priv->dev, "qca,led-open-drain require qca,ignore-power-on-sel to be set.");
+			return -EINVAL;
+		}
+
+		val |= QCA8K_PWS_LED_OPEN_EN_CSR;
+	}
+
+	return qca8k_rmw(priv, QCA8K_REG_PWS,
+			QCA8K_PWS_LED_OPEN_EN_CSR | QCA8K_PWS_POWER_ON_SEL,
+			val);
+}
+
 static int
 qca8k_parse_port_config(struct qca8k_priv *priv)
 {
@@ -1053,6 +1088,10 @@ qca8k_setup(struct dsa_switch *ds)
 	if (ret)
 		return ret;
 
+	ret = qca8k_setup_of_pws_reg(priv);
+	if (ret)
+		return ret;
+
 	ret = qca8k_setup_mac_pwr_sel(priv);
 	if (ret)
 		return ret;

drivers/net/dsa/qca8k.h

@@ -46,6 +46,12 @@
 #define   QCA8K_MAX_DELAY				3
 #define   QCA8K_PORT_PAD_SGMII_EN			BIT(7)
 #define QCA8K_REG_PWS					0x010
+#define   QCA8K_PWS_POWER_ON_SEL			BIT(31)
+/* This reg is only valid for QCA832x and toggle the package
+ * type from 176 pin (by default) to 148 pin used on QCA8327
+ */
+#define   QCA8327_PWS_PACKAGE148_EN			BIT(30)
+#define   QCA8K_PWS_LED_OPEN_EN_CSR			BIT(24)
 #define   QCA8K_PWS_SERDES_AEN_DIS			BIT(7)
 #define QCA8K_REG_MODULE_EN				0x030
 #define   QCA8K_MODULE_EN_MIB				BIT(0)