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drivers/hwmon: max31785 Set fan fault response based on dev tree

PATCH Applied Christopher Bostic 2 participants 2 messages Jun 20, 2017 – Jun 21, 2017 Hardware monitoring

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Christopher Bostic

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#0 lore raw

PATCH 1/1 drivers/hwmon: max31785 Set fan fault response based on dev tree

Check for the optional device tree property 'fault-max-fan'. If present, configure hardware for 100% PWM fan duty cycle on fault condition.

Signed-off-by Christopher Bostic <[email protected]>

---
v3 - Change bit field definition to use macro BIT(x)
- Set all 6 fans to same fault response
- Rename fault response register #define to match the spec

v2 - Set 4 fans to same fault response

---
 drivers/hwmon/max31785.c | 37 +++++++++++++++++++++++++++++++++++++
 1 file changed, 37 insertions(+)
drivers/hwmon/max31785.c +37 -0
index fc03b7c..4010504 100644
@@ -38,6 +38,7 @@
 #define MAX31785_REG_MFR_ID			0x99
 #define MAX31785_REG_MFR_MODEL			0x9a
 #define MAX31785_REG_MFR_REVISION		0x9b
+#define MAX31785_REG_MFR_FAULT_RESP		0xd9
 #define MAX31785_REG_MFR_FAN_CONFIG		0xf1
 #define MAX31785_REG_READ_FAN_PWM		0xf3
 

@@ -51,6 +52,9 @@
 /* Fan Status register bits */
 #define MAX31785_FAN_STATUS_FAULT_MASK		0x80
 
+/* Fault response register bits */
+#define MAX31785_FAULT_PIN_MONITOR		BIT(0)
+
 /* Fan Command constants */
 #define MAX31785_FAN_COMMAND_PWM_RATIO		40
 

@@ -762,6 +766,35 @@ static int max31785_get_capabilities(struct max31785 *data)
 	return 0;
 }
 
+static int max31785_init_fault_resp(struct i2c_client *client)
+{
+	struct device_node *np = client->dev.of_node;
+	int page;
+	int rc;
+
+	if (np && of_get_property(np, "fault-max-fan", NULL)) {
+		for (page = 0; page < NR_CHANNEL; page++) {
+
+			/* set max fans on fault */
+			rc = max31785_set_page(client, page);
+			if (rc < 0)
+				return rc;
+
+			rc = i2c_smbus_read_byte_data(client,
+					MAX31785_REG_MFR_FAULT_RESP);
+			if (rc < 0)
+				return rc;
+
+			rc |= MAX31785_FAULT_PIN_MONITOR;
+			rc = i2c_smbus_write_byte_data(client,
+					MAX31785_REG_MFR_FAULT_RESP, rc);
+		}
+		return rc;
+	}
+
+	return 0;
+}
+
 static int max31785_probe(struct i2c_client *client,
 			  const struct i2c_device_id *id)
 {

@@ -783,6 +816,10 @@ static int max31785_probe(struct i2c_client *client,
 	data->client = client;
 	mutex_init(&data->lock);
 
+	rc = max31785_init_fault_resp(client);
+	if (rc)
+		return rc;
+
 	rc = max31785_init_fans(data);
 	if (rc)
 		return rc;
Signature · 1 line
1.8.2.2
Applied
#1 lore raw
Quoted 9 lines · Christopher Bostic

Check for the optional device tree property 'fault-max-fan'. If present, configure hardware for 100% PWM fan duty cycle on fault condition.

Signed-off-by Christopher Bostic <[email protected]>

---
v3 - Change bit field definition to use macro BIT(x)
- Set all 6 fans to same fault response
- Rename fault response register #define to match the spec

Applied to dev-4.10.

Cheers,

Joel

Quoted 29 lines

v2 - Set 4 fans to same fault response

---
 drivers/hwmon/max31785.c | 37 +++++++++++++++++++++++++++++++++++++
 1 file changed, 37 insertions(+)
drivers/hwmon/max31785.c +4 -0
index fc03b7c..4010504 100644
@@ -38,6 +38,7 @@
 #define MAX31785_REG_MFR_ID                    0x99
 #define MAX31785_REG_MFR_MODEL                 0x9a
 #define MAX31785_REG_MFR_REVISION              0x9b
+#define MAX31785_REG_MFR_FAULT_RESP            0xd9
 #define MAX31785_REG_MFR_FAN_CONFIG            0xf1
 #define MAX31785_REG_READ_FAN_PWM              0xf3
 

@@ -51,6 +52,9 @@
 /* Fan Status register bits */
 #define MAX31785_FAN_STATUS_FAULT_MASK         0x80
 
+/* Fault response register bits */
+#define MAX31785_FAULT_PIN_MONITOR             BIT(0)
+
 /* Fan Command constants */
 #define MAX31785_FAN_COMMAND_PWM_RATIO         40

drivers/hwmon/max31785.c static int max31785_get_capabilities(struct max31785 *data) · line 775

Quoted 10 lines
drivers/hwmon/max31785.c +7 -0
@@ -762,6 +766,35 @@ static int max31785_get_capabilities(struct max31785 *data)
        return 0;
 }
 
+static int max31785_init_fault_resp(struct i2c_client *client)
+{
+       struct device_node *np = client->dev.of_node;
+       int page;
+       int rc;
+
+       if (np && of_get_property(np, "fault-max-fan", NULL)) {

For reference, you can use of_property_read_bool here.

Quoted 39 lines
drivers/hwmon/max31785.c +26 -1
+               for (page = 0; page < NR_CHANNEL; page++) {
+
+                       /* set max fans on fault */
+                       rc = max31785_set_page(client, page);
+                       if (rc < 0)
+                               return rc;
+
+                       rc = i2c_smbus_read_byte_data(client,
+                                       MAX31785_REG_MFR_FAULT_RESP);
+                       if (rc < 0)
+                               return rc;
+
+                       rc |= MAX31785_FAULT_PIN_MONITOR;
+                       rc = i2c_smbus_write_byte_data(client,
+                                       MAX31785_REG_MFR_FAULT_RESP, rc);
+               }
+               return rc;
+       }
+
+       return 0;
+}
+
 static int max31785_probe(struct i2c_client *client,
                          const struct i2c_device_id *id)
 {

@@ -783,6 +816,10 @@ static int max31785_probe(struct i2c_client *client,
        data->client = client;
        mutex_init(&data->lock);
 
+       rc = max31785_init_fault_resp(client);
+       if (rc)
+               return rc;
+
        rc = max31785_init_fans(data);
        if (rc)
                return rc;
--

1.8.2.2