[PATCH] hwmon: tps23861: add support for initializing the chip

[Andreas Böhler <dev@xxxxxxxxxxx>]

The tps23861 driver does not initialize the chip and relies on it being
in auto-mode by default. On some devices, these controllers default to
OFF-Mode and hence cannot be used at all.

This brings minimal support for initializing the controller in a user-
defined mode.

Tested on a TP-Link TL-SG2452P with 12x TI TPS23861 controllers.

Note: The DT bindings still need to be updated.

Usage:

tps23861@9 {
	compatible = "ti,tps23861";
	reg = <0x09>;

	port@0 {
		reg = <0>;
		mode = "auto";
		enable = <1>;
		poe_plus = <1>;
	};

	port@1 {
		reg = <1>;
		mode = "auto";
		enable = <1>;
		poe_plus = <1>;
	};

	port@2 {
		reg = <2>;
		mode = "auto";
		enable = <1>;
		poe_plus = <1>;
	};

	port@3 {
		reg = <3>;
		mode = "auto";
		enable = <1>;
		poe_plus = <1>;
	};
};

Signed-off-by: Andreas Böhler <dev@xxxxxxxxxxx>
---
 drivers/hwmon/tps23861.c | 81 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 81 insertions(+)

diff --git a/drivers/hwmon/tps23861.c b/drivers/hwmon/tps23861.c
index 42762e87b014..27bf8716cf12 100644
--- a/drivers/hwmon/tps23861.c
+++ b/drivers/hwmon/tps23861.c
@@ -85,6 +85,8 @@
 #define PORT_DETECT_CAPACITANCE_INVALID_DELTA	11
 #define PORT_DETECT_CAPACITANCE_OUT_OF_RANGE	12
 #define POE_PLUS			0x40
+#define POE_PLUS_MASK(_port)	\
+	GENMASK(_port + 4, _port + 4)
 #define OPERATING_MODE			0x12
 #define OPERATING_MODE_OFF		0
 #define OPERATING_MODE_MANUAL		1
@@ -94,9 +96,22 @@
 #define OPERATING_MODE_PORT_2_MASK	GENMASK(3, 2)
 #define OPERATING_MODE_PORT_3_MASK	GENMASK(5, 4)
 #define OPERATING_MODE_PORT_4_MASK	GENMASK(7, 6)
+#define OPERATING_MODE_PORT(_mode, _port)	\
+	(_mode << (_port * 2))
 
+#define DISCONNECT_ENABLE		0x13
+#define DISCONNECT_ENABLE_MASK(_port)	\
+	GENMASK(_port, _port)
+#define DISCONNECT_MASK(_port)	\
+	(GENMASK(_port, _port) | GENMASK(_port + 4, _port + 4))
+
+#define DETECT_CLASS_ENABLE		0x14
 #define DETECT_CLASS_RESTART		0x18
 #define POWER_ENABLE			0x19
+#define POWER_ENABLE_ON_MASK(_port)	\
+	GENMASK(_port, _port)
+#define POWER_ENABLE_OFF_MASK(_port)	\
+	GENMASK(_port + 4, _port + 4)
 #define TPS23861_NUM_PORTS		4
 
 #define TPS23861_GENERAL_MASK_1		0x17
@@ -548,7 +563,16 @@ static int tps23861_probe(struct i2c_client *client)
 	struct device *dev = &client->dev;
 	struct tps23861_data *data;
 	struct device *hwmon_dev;
+	struct device_node *child;
 	u32 shunt_resistor;
+	u32 reg;
+	u32 temp;
+	const char *mode;
+	unsigned int poe_plusval;
+	unsigned int mode_val;
+	unsigned int power_val;
+	unsigned int enable_val;
+	unsigned int disconnect_enable_val;
 
 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
 	if (!data)
@@ -577,6 +601,63 @@ static int tps23861_probe(struct i2c_client *client)
 				TPS23861_GENERAL_MASK_1,
 				TPS23861_CURRENT_SHUNT_MASK);
 
+	regmap_read(data->regmap, POE_PLUS, &poe_plusval);
+	regmap_read(data->regmap, POWER_ENABLE, &power_val);
+	regmap_read(data->regmap, OPERATING_MODE, &mode_val);
+	regmap_read(data->regmap, DETECT_CLASS_ENABLE, &enable_val);
+	regmap_read(data->regmap, DISCONNECT_ENABLE, &disconnect_enable_val);
+
+	for_each_child_of_node(dev->of_node, child) {
+		if (of_property_read_u32(child, "reg", &reg))
+			continue;
+
+		if (reg > (TPS23861_NUM_PORTS - 1) || reg < 0)
+			continue;
+
+		if (!of_property_read_string(child, "mode", &mode)) {
+			if (!strncmp(mode, "manual", 6)) {
+				mode_val &= ~OPERATING_MODE_PORT(OPERATING_MODE_AUTO, reg);
+				mode_val |= OPERATING_MODE_PORT(OPERATING_MODE_MANUAL, reg);
+			} else if (!strncmp(mode, "semiauto", 8)) {
+				mode_val &= ~OPERATING_MODE_PORT(OPERATING_MODE_AUTO, reg);
+				mode_val |= OPERATING_MODE_PORT(OPERATING_MODE_SEMI, reg);
+			} else if (!strncmp(mode, "auto", 4))
+				mode_val |= OPERATING_MODE_PORT(OPERATING_MODE_AUTO, reg);
+			else
+				mode_val &= ~OPERATING_MODE_PORT(OPERATING_MODE_AUTO, reg);
+		}
+
+		if (!of_property_read_u32(child, "enable", &temp)) {
+			if (temp) {
+				enable_val |= DISCONNECT_MASK(reg);
+				disconnect_enable_val |= DISCONNECT_ENABLE_MASK(reg);
+			} else {
+				enable_val &= ~DISCONNECT_MASK(reg);
+				disconnect_enable_val &= ~DISCONNECT_ENABLE_MASK(reg);
+			}
+		}
+
+		if (!of_property_read_u32(child, "power", &temp)) {
+			if (temp)
+				power_val |= POWER_ENABLE_ON_MASK(reg);
+			else
+				power_val |= POWER_ENABLE_OFF_MASK(reg);
+		}
+
+		if (!of_property_read_u32(child, "poe_plus", &temp)) {
+			if (temp)
+				poe_plusval |= POE_PLUS_MASK(reg);
+			else
+				poe_plusval &= ~POE_PLUS_MASK(reg);
+		}
+	}
+
+	regmap_write(data->regmap, POE_PLUS, poe_plusval);
+	regmap_write(data->regmap, POWER_ENABLE, power_val);
+	regmap_write(data->regmap, OPERATING_MODE, mode_val);
+	regmap_write(data->regmap, DETECT_CLASS_ENABLE, enable_val);
+	regmap_write(data->regmap, DISCONNECT_ENABLE, disconnect_enable_val);
+
 	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
 							 data, &tps23861_chip_info,
 							 NULL);
-- 
2.37.2