hwmon: (pmbus): Add generic alarm bit for iin and pin

Add PB_STATUS_INPUT as the generic alarm bit for iin and pin. We also
need to redo the status register checking before setting up the boolean
attribute, since it won't necessarily check STATUS_WORD if the device
doesn't support it, which we need for this bit.

Signed-off-by: Edward A. James <eajames@us.ibm.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

drivers/hwmon/pmbus/pmbus_core.c

@@ -114,6 +114,7 @@ struct pmbus_data {
 	 */
 	u16 status[PB_NUM_STATUS_REG];
 
+	bool has_status_word;		/* device uses STATUS_WORD register */
 	int (*read_status)(struct i2c_client *client, int page);
 
 	u8 currpage;
@@ -1045,6 +1046,7 @@ static int pmbus_add_sensor_attrs_one(struct i2c_client *client,
 				      const struct pmbus_sensor_attr *attr)
 {
 	struct pmbus_sensor *base;
+	bool upper = !!(attr->gbit & 0xff00);	/* need to check STATUS_WORD */
 	int ret;
 
 	if (attr->label) {
@@ -1065,9 +1067,11 @@ static int pmbus_add_sensor_attrs_one(struct i2c_client *client,
 		/*
 		 * Add generic alarm attribute only if there are no individual
 		 * alarm attributes, if there is a global alarm bit, and if
-		 * the generic status register for this page is accessible.
+		 * the generic status register (word or byte, depending on
+		 * which global bit is set) for this page is accessible.
 		 */
 		if (!ret && attr->gbit &&
+		    (!upper || (upper && data->has_status_word)) &&
 		    pmbus_check_status_register(client, page)) {
 			ret = pmbus_add_boolean(data, name, "alarm", index,
 						NULL, NULL,
@@ -1324,6 +1328,7 @@ static const struct pmbus_sensor_attr current_attributes[] = {
 		.func = PMBUS_HAVE_IIN,
 		.sfunc = PMBUS_HAVE_STATUS_INPUT,
 		.sbase = PB_STATUS_INPUT_BASE,
+		.gbit = PB_STATUS_INPUT,
 		.limit = iin_limit_attrs,
 		.nlimit = ARRAY_SIZE(iin_limit_attrs),
 	}, {
@@ -1408,6 +1413,7 @@ static const struct pmbus_sensor_attr power_attributes[] = {
 		.func = PMBUS_HAVE_PIN,
 		.sfunc = PMBUS_HAVE_STATUS_INPUT,
 		.sbase = PB_STATUS_INPUT_BASE,
+		.gbit = PB_STATUS_INPUT,
 		.limit = pin_limit_attrs,
 		.nlimit = ARRAY_SIZE(pin_limit_attrs),
 	}, {
@@ -1775,6 +1781,8 @@ static int pmbus_init_common(struct i2c_client *client, struct pmbus_data *data,
 			dev_err(dev, "PMBus status register not found\n");
 			return -ENODEV;
 		}
+	} else {
+		data->has_status_word = true;
 	}
 
 	/* Enable PEC if the controller supports it */