hwmon: (corsair-psu) add support for critical values

Adds support for reading the critical values of the temperature sensors
and the rail sensors (voltage and current) once and caches them. Updates
the naming of the constants following a more clear scheme. Also updates
the documentation and fixes some typos. Updates is_visible and ops_read
functions to be more readable.

The new sensors output of a Corsair HX850i will look like this:
corsairpsu-hid-3-1
Adapter: HID adapter
v_in:        230.00 V
v_out +12v:   12.14 V  (crit min =  +8.41 V, crit max = +15.59 V)
v_out +5v:     5.03 V  (crit min =  +3.50 V, crit max =  +6.50 V)
v_out +3.3v:   3.30 V  (crit min =  +2.31 V, crit max =  +4.30 V)
psu fan:        0 RPM
vrm temp:     +46.2°C  (crit = +70.0°C)
case temp:    +39.8°C  (crit = +70.0°C)
power total: 152.00 W
power +12v:  108.00 W
power +5v:    41.00 W
power +3.3v:   5.00 W
curr +12v:     9.00 A  (crit max = +85.00 A)
curr +5v:      8.31 A  (crit max = +40.00 A)
curr +3.3v:    1.62 A  (crit max = +40.00 A)
Signed-off-by: Wilken Gottwalt <wilken.gottwalt@posteo.net>
Link: https://lore.kernel.org/r/YFNg6vGk3sQmyqgB@monster.powergraphx.localSigned-off-by: Guenter Roeck <linux@roeck-us.net>

Documentation/hwmon/corsair-psu.rst

@@ -47,19 +47,30 @@ Sysfs entries
 =======================	========================================================
 curr1_input		Total current usage
 curr2_input		Current on the 12v psu rail
+curr2_crit		Current max critical value on the 12v psu rail
 curr3_input		Current on the 5v psu rail
+curr3_crit		Current max critical value on the 5v psu rail
 curr4_input		Current on the 3.3v psu rail
+curr4_crit		Current max critical value on the 3.3v psu rail
 fan1_input		RPM of psu fan
 in0_input		Voltage of the psu ac input
 in1_input		Voltage of the 12v psu rail
+in1_crit		Voltage max critical value on the 12v psu rail
+in1_lcrit		Voltage min critical value on the 12v psu rail
 in2_input		Voltage of the 5v psu rail
-in3_input		Voltage of the 3.3 psu rail
+in2_crit		Voltage max critical value on the 5v psu rail
+in2_lcrit		Voltage min critical value on the 5v psu rail
+in3_input		Voltage of the 3.3v psu rail
+in3_crit		Voltage max critical value on the 3.3v psu rail
+in3_lcrit		Voltage min critical value on the 3.3v psu rail
 power1_input		Total power usage
 power2_input		Power usage of the 12v psu rail
 power3_input		Power usage of the 5v psu rail
 power4_input		Power usage of the 3.3v psu rail
 temp1_input		Temperature of the psu vrm component
+temp1_crit		Temperature max cirtical value of the psu vrm component
 temp2_input		Temperature of the psu case
+temp2_crit		Temperature max critical value of psu case
 =======================	========================================================
 
 Usage Notes

drivers/hwmon/corsair-psu.c

@@ -53,11 +53,17 @@
 #define CMD_TIMEOUT_MS		250
 #define SECONDS_PER_HOUR	(60 * 60)
 #define SECONDS_PER_DAY		(SECONDS_PER_HOUR * 24)
+#define RAIL_COUNT		3 /* 3v3 + 5v + 12v */
+#define TEMP_COUNT		2
 
 #define PSU_CMD_SELECT_RAIL	0x00 /* expects length 2 */
-#define PSU_CMD_IN_VOLTS	0x88 /* the rest of the commands expect length 3 */
+#define PSU_CMD_RAIL_VOLTS_HCRIT 0x40 /* the rest of the commands expect length 3 */
+#define PSU_CMD_RAIL_VOLTS_LCRIT 0x44
+#define PSU_CMD_RAIL_AMPS_HCRIT	0x46
+#define PSU_CMD_TEMP_HCRIT	0x4F
+#define PSU_CMD_IN_VOLTS	0x88
 #define PSU_CMD_IN_AMPS		0x89
-#define PSU_CMD_RAIL_OUT_VOLTS	0x8B
+#define PSU_CMD_RAIL_VOLTS	0x8B
 #define PSU_CMD_RAIL_AMPS	0x8C
 #define PSU_CMD_TEMP0		0x8D
 #define PSU_CMD_TEMP1		0x8E
@@ -116,6 +122,15 @@ struct corsairpsu_data {
 	u8 *cmd_buffer;
 	char vendor[REPLY_SIZE];
 	char product[REPLY_SIZE];
+	long temp_crit[TEMP_COUNT];
+	long in_crit[RAIL_COUNT];
+	long in_lcrit[RAIL_COUNT];
+	long curr_crit[RAIL_COUNT];
+	u8 temp_crit_support;
+	u8 in_crit_support;
+	u8 in_lcrit_support;
+	u8 curr_crit_support;
+	bool in_curr_cmd_support; /* not all commands are supported on every PSU */
 };
 
 /* some values are SMBus LINEAR11 data which need a conversion */
@@ -193,7 +208,10 @@ static int corsairpsu_request(struct corsairpsu_data *priv, u8 cmd, u8 rail, voi
 
 	mutex_lock(&priv->lock);
 	switch (cmd) {
-	case PSU_CMD_RAIL_OUT_VOLTS:
+	case PSU_CMD_RAIL_VOLTS_HCRIT:
+	case PSU_CMD_RAIL_VOLTS_LCRIT:
+	case PSU_CMD_RAIL_AMPS_HCRIT:
+	case PSU_CMD_RAIL_VOLTS:
 	case PSU_CMD_RAIL_AMPS:
 	case PSU_CMD_RAIL_WATTS:
 		ret = corsairpsu_usb_cmd(priv, 2, PSU_CMD_SELECT_RAIL, rail, NULL);
@@ -229,9 +247,13 @@ static int corsairpsu_get_value(struct corsairpsu_data *priv, u8 cmd, u8 rail, l
 	 */
 	tmp = ((long)data[3] << 24) + (data[2] << 16) + (data[1] << 8) + data[0];
 	switch (cmd) {
+	case PSU_CMD_RAIL_VOLTS_HCRIT:
+	case PSU_CMD_RAIL_VOLTS_LCRIT:
+	case PSU_CMD_RAIL_AMPS_HCRIT:
+	case PSU_CMD_TEMP_HCRIT:
 	case PSU_CMD_IN_VOLTS:
 	case PSU_CMD_IN_AMPS:
-	case PSU_CMD_RAIL_OUT_VOLTS:
+	case PSU_CMD_RAIL_VOLTS:
 	case PSU_CMD_RAIL_AMPS:
 	case PSU_CMD_TEMP0:
 	case PSU_CMD_TEMP1:
@@ -256,75 +278,265 @@ static int corsairpsu_get_value(struct corsairpsu_data *priv, u8 cmd, u8 rail, l
 	return ret;
 }
 
-static umode_t corsairpsu_hwmon_ops_is_visible(const void *data, enum hwmon_sensor_types type,
-					       u32 attr, int channel)
+static void corsairpsu_get_criticals(struct corsairpsu_data *priv)
 {
-	if (type == hwmon_temp && (attr == hwmon_temp_input || attr == hwmon_temp_label))
-		return 0444;
-	else if (type == hwmon_fan && (attr == hwmon_fan_input || attr == hwmon_fan_label))
-		return 0444;
-	else if (type == hwmon_power && (attr == hwmon_power_input || attr == hwmon_power_label))
-		return 0444;
-	else if (type == hwmon_in && (attr == hwmon_in_input || attr == hwmon_in_label))
+	long tmp;
+	int rail;
+
+	for (rail = 0; rail < TEMP_COUNT; ++rail) {
+		if (!corsairpsu_get_value(priv, PSU_CMD_TEMP_HCRIT, rail, &tmp)) {
+			priv->temp_crit_support |= BIT(rail);
+			priv->temp_crit[rail] = tmp;
+		}
+	}
+
+	for (rail = 0; rail < RAIL_COUNT; ++rail) {
+		if (!corsairpsu_get_value(priv, PSU_CMD_RAIL_VOLTS_HCRIT, rail, &tmp)) {
+			priv->in_crit_support |= BIT(rail);
+			priv->in_crit[rail] = tmp;
+		}
+
+		if (!corsairpsu_get_value(priv, PSU_CMD_RAIL_VOLTS_LCRIT, rail, &tmp)) {
+			priv->in_lcrit_support |= BIT(rail);
+			priv->in_lcrit[rail] = tmp;
+		}
+
+		if (!corsairpsu_get_value(priv, PSU_CMD_RAIL_AMPS_HCRIT, rail, &tmp)) {
+			priv->curr_crit_support |= BIT(rail);
+			priv->curr_crit[rail] = tmp;
+		}
+	}
+}
+
+static void corsairpsu_check_cmd_support(struct corsairpsu_data *priv)
+{
+	long tmp;
+
+	priv->in_curr_cmd_support = !corsairpsu_get_value(priv, PSU_CMD_IN_AMPS, 0, &tmp);
+}
+
+static umode_t corsairpsu_hwmon_temp_is_visible(const struct corsairpsu_data *priv, u32 attr,
+						int channel)
+{
+	umode_t res = 0444;
+
+	switch (attr) {
+	case hwmon_temp_input:
+	case hwmon_temp_label:
+	case hwmon_temp_crit:
+		if (channel > 0 && !(priv->temp_crit_support & BIT(channel - 1)))
+			res = 0;
+		break;
+	default:
+		break;
+	}
+
+	return res;
+}
+
+static umode_t corsairpsu_hwmon_fan_is_visible(const struct corsairpsu_data *priv, u32 attr,
+					       int channel)
+{
+	switch (attr) {
+	case hwmon_fan_input:
+	case hwmon_fan_label:
 		return 0444;
-	else if (type == hwmon_curr && (attr == hwmon_curr_input || attr == hwmon_curr_label))
+	default:
+		return 0;
+	}
+}
+
+static umode_t corsairpsu_hwmon_power_is_visible(const struct corsairpsu_data *priv, u32 attr,
+						 int channel)
+{
+	switch (attr) {
+	case hwmon_power_input:
+	case hwmon_power_label:
 		return 0444;
+	default:
+		return 0;
+	};
+}
 
-	return 0;
+static umode_t corsairpsu_hwmon_in_is_visible(const struct corsairpsu_data *priv, u32 attr,
+					      int channel)
+{
+	umode_t res = 0444;
+
+	switch (attr) {
+	case hwmon_in_input:
+	case hwmon_in_label:
+	case hwmon_in_crit:
+		if (channel > 0 && !(priv->in_crit_support & BIT(channel - 1)))
+			res = 0;
+		break;
+	case hwmon_in_lcrit:
+		if (channel > 0 && !(priv->in_lcrit_support & BIT(channel - 1)))
+			res = 0;
+		break;
+	default:
+		break;
+	};
+
+	return res;
 }
 
-static int corsairpsu_hwmon_ops_read(struct device *dev, enum hwmon_sensor_types type, u32 attr,
-				     int channel, long *val)
+static umode_t corsairpsu_hwmon_curr_is_visible(const struct corsairpsu_data *priv, u32 attr,
+						int channel)
 {
-	struct corsairpsu_data *priv = dev_get_drvdata(dev);
-	int ret;
+	umode_t res = 0444;
 
-	if (type == hwmon_temp && attr == hwmon_temp_input && channel < 2) {
-		ret = corsairpsu_get_value(priv, channel ? PSU_CMD_TEMP1 : PSU_CMD_TEMP0, channel,
-					   val);
-	} else if (type == hwmon_fan && attr == hwmon_fan_input) {
-		ret = corsairpsu_get_value(priv, PSU_CMD_FAN, 0, val);
-	} else if (type == hwmon_power && attr == hwmon_power_input) {
+	switch (attr) {
+	case hwmon_curr_input:
+		if (channel == 0 && !priv->in_curr_cmd_support)
+			res = 0;
+		break;
+	case hwmon_curr_label:
+	case hwmon_curr_crit:
+		if (channel > 0 && !(priv->curr_crit_support & BIT(channel - 1)))
+			res = 0;
+		break;
+	default:
+		break;
+	}
+
+	return res;
+}
+
+static umode_t corsairpsu_hwmon_ops_is_visible(const void *data, enum hwmon_sensor_types type,
+					       u32 attr, int channel)
+{
+	const struct corsairpsu_data *priv = data;
+
+	switch (type) {
+	case hwmon_temp:
+		return corsairpsu_hwmon_temp_is_visible(priv, attr, channel);
+	case hwmon_fan:
+		return corsairpsu_hwmon_fan_is_visible(priv, attr, channel);
+	case hwmon_power:
+		return corsairpsu_hwmon_power_is_visible(priv, attr, channel);
+	case hwmon_in:
+		return corsairpsu_hwmon_in_is_visible(priv, attr, channel);
+	case hwmon_curr:
+		return corsairpsu_hwmon_curr_is_visible(priv, attr, channel);
+	default:
+		return 0;
+	}
+}
+
+static int corsairpsu_hwmon_temp_read(struct corsairpsu_data *priv, u32 attr, int channel,
+				      long *val)
+{
+	int err = -EOPNOTSUPP;
+
+	switch (attr) {
+	case hwmon_temp_input:
+		return corsairpsu_get_value(priv, channel ? PSU_CMD_TEMP1 : PSU_CMD_TEMP0,
+					    channel, val);
+	case hwmon_temp_crit:
+		*val = priv->temp_crit[channel];
+		err = 0;
+		break;
+	default:
+		break;
+	}
+
+	return err;
+}
+
+static int corsairpsu_hwmon_power_read(struct corsairpsu_data *priv, u32 attr, int channel,
+				       long *val)
+{
+	if (attr == hwmon_power_input) {
 		switch (channel) {
 		case 0:
-			ret = corsairpsu_get_value(priv, PSU_CMD_TOTAL_WATTS, 0, val);
-			break;
+			return corsairpsu_get_value(priv, PSU_CMD_TOTAL_WATTS, 0, val);
 		case 1 ... 3:
-			ret = corsairpsu_get_value(priv, PSU_CMD_RAIL_WATTS, channel - 1, val);
-			break;
+			return corsairpsu_get_value(priv, PSU_CMD_RAIL_WATTS, channel - 1, val);
 		default:
-			return -EOPNOTSUPP;
+			break;
 		}
-	} else if (type == hwmon_in && attr == hwmon_in_input) {
+	}
+
+	return -EOPNOTSUPP;
+}
+
+static int corsairpsu_hwmon_in_read(struct corsairpsu_data *priv, u32 attr, int channel, long *val)
+{
+	int err = -EOPNOTSUPP;
+
+	switch (attr) {
+	case hwmon_in_input:
 		switch (channel) {
 		case 0:
-			ret = corsairpsu_get_value(priv, PSU_CMD_IN_VOLTS, 0, val);
-			break;
+			return corsairpsu_get_value(priv, PSU_CMD_IN_VOLTS, 0, val);
 		case 1 ... 3:
-			ret = corsairpsu_get_value(priv, PSU_CMD_RAIL_OUT_VOLTS, channel - 1, val);
-			break;
+			return corsairpsu_get_value(priv, PSU_CMD_RAIL_VOLTS, channel - 1, val);
 		default:
-			return -EOPNOTSUPP;
+			break;
 		}
-	} else if (type == hwmon_curr && attr == hwmon_curr_input) {
+		break;
+	case hwmon_in_crit:
+		*val = priv->in_crit[channel - 1];
+		err = 0;
+		break;
+	case hwmon_in_lcrit:
+		*val = priv->in_lcrit[channel - 1];
+		err = 0;
+		break;
+	}
+
+	return err;
+}
+
+static int corsairpsu_hwmon_curr_read(struct corsairpsu_data *priv, u32 attr, int channel,
+				      long *val)
+{
+	int err = -EOPNOTSUPP;
+
+	switch (attr) {
+	case hwmon_curr_input:
 		switch (channel) {
 		case 0:
-			ret = corsairpsu_get_value(priv, PSU_CMD_IN_AMPS, 0, val);
-			break;
+			return corsairpsu_get_value(priv, PSU_CMD_IN_AMPS, 0, val);
 		case 1 ... 3:
-			ret = corsairpsu_get_value(priv, PSU_CMD_RAIL_AMPS, channel - 1, val);
-			break;
+			return corsairpsu_get_value(priv, PSU_CMD_RAIL_AMPS, channel - 1, val);
 		default:
-			return -EOPNOTSUPP;
+			break;
 		}
-	} else {
-		return -EOPNOTSUPP;
+		break;
+	case hwmon_curr_crit:
+		*val = priv->curr_crit[channel - 1];
+		err = 0;
+		break;
+	default:
+		break;
 	}
 
-	if (ret < 0)
-		return ret;
+	return err;
+}
 
-	return 0;
+static int corsairpsu_hwmon_ops_read(struct device *dev, enum hwmon_sensor_types type, u32 attr,
+				     int channel, long *val)
+{
+	struct corsairpsu_data *priv = dev_get_drvdata(dev);
+
+	switch (type) {
+	case hwmon_temp:
+		return corsairpsu_hwmon_temp_read(priv, attr, channel, val);
+	case hwmon_fan:
+		if (attr == hwmon_fan_input)
+			return corsairpsu_get_value(priv, PSU_CMD_FAN, 0, val);
+		return -EOPNOTSUPP;
+	case hwmon_power:
+		return corsairpsu_hwmon_power_read(priv, attr, channel, val);
+	case hwmon_in:
+		return corsairpsu_hwmon_in_read(priv, attr, channel, val);
+	case hwmon_curr:
+		return corsairpsu_hwmon_curr_read(priv, attr, channel, val);
+	default:
+		return -EOPNOTSUPP;
+	}
 }
 
 static int corsairpsu_hwmon_ops_read_string(struct device *dev, enum hwmon_sensor_types type,
@@ -360,8 +572,8 @@ static const struct hwmon_channel_info *corsairpsu_info[] = {
 	HWMON_CHANNEL_INFO(chip,
 			   HWMON_C_REGISTER_TZ),
 	HWMON_CHANNEL_INFO(temp,
-			   HWMON_T_INPUT | HWMON_T_LABEL,
-			   HWMON_T_INPUT | HWMON_T_LABEL),
+			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
+			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT),
 	HWMON_CHANNEL_INFO(fan,
 			   HWMON_F_INPUT | HWMON_F_LABEL),
 	HWMON_CHANNEL_INFO(power,
@@ -371,14 +583,14 @@ static const struct hwmon_channel_info *corsairpsu_info[] = {
 			   HWMON_P_INPUT | HWMON_P_LABEL),
 	HWMON_CHANNEL_INFO(in,
 			   HWMON_I_INPUT | HWMON_I_LABEL,
-			   HWMON_I_INPUT | HWMON_I_LABEL,
-			   HWMON_I_INPUT | HWMON_I_LABEL,
-			   HWMON_I_INPUT | HWMON_I_LABEL),
+			   HWMON_I_INPUT | HWMON_I_LABEL | HWMON_I_LCRIT | HWMON_I_CRIT,
+			   HWMON_I_INPUT | HWMON_I_LABEL | HWMON_I_LCRIT | HWMON_I_CRIT,
+			   HWMON_I_INPUT | HWMON_I_LABEL | HWMON_I_LCRIT | HWMON_I_CRIT),
 	HWMON_CHANNEL_INFO(curr,
 			   HWMON_C_INPUT | HWMON_C_LABEL,
-			   HWMON_C_INPUT | HWMON_C_LABEL,
-			   HWMON_C_INPUT | HWMON_C_LABEL,
-			   HWMON_C_INPUT | HWMON_C_LABEL),
+			   HWMON_C_INPUT | HWMON_C_LABEL | HWMON_C_CRIT,
+			   HWMON_C_INPUT | HWMON_C_LABEL | HWMON_C_CRIT,
+			   HWMON_C_INPUT | HWMON_C_LABEL | HWMON_C_CRIT),
 	NULL
 };
 
@@ -513,6 +725,9 @@ static int corsairpsu_probe(struct hid_device *hdev, const struct hid_device_id
 		goto fail_and_stop;
 	}
 
+	corsairpsu_get_criticals(priv);
+	corsairpsu_check_cmd_support(priv);
+
 	priv->hwmon_dev = hwmon_device_register_with_info(&hdev->dev, "corsairpsu", priv,
 							  &corsairpsu_chip_info, 0);