hwmon: (adt7475) Rework voltage inputs handling

Rework the handling of voltage inputs to make it possible and easy to
support more inputs. This will be needed for the upcoming ADT7490
support.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Jordan Crouse <jordan@cosmicpenguin.net>
Cc: "Darrick J. Wong" <djwong@us.ibm.com>

1 files changed, 48 insertions, 35 deletions

diff --git a/drivers/hwmon/adt7475.c b/drivers/hwmon/adt7475.c
index 188ae428ccd..e9f69ee197d 100644
--- a/drivers/hwmon/adt7475.c
+++ b/drivers/hwmon/adt7475.c
@@ -39,7 +39,7 @@
 
 /* 7475 Common Registers */
 
-#define REG_VOLTAGE_BASE        0x21
+#define REG_VOLTAGE_BASE        0x20
 #define REG_TEMP_BASE           0x25
 #define REG_TACH_BASE           0x28
 #define REG_PWM_BASE            0x30
@@ -51,8 +51,8 @@
 #define REG_STATUS1             0x41
 #define REG_STATUS2             0x42
 
-#define REG_VOLTAGE_MIN_BASE    0x46
-#define REG_VOLTAGE_MAX_BASE    0x47
+#define REG_VOLTAGE_MIN_BASE    0x44
+#define REG_VOLTAGE_MAX_BASE    0x45
 
 #define REG_TEMP_MIN_BASE       0x4E
 #define REG_TEMP_MAX_BASE       0x4F
@@ -85,7 +85,7 @@
 
 /* ADT7475 Settings */
 
-#define ADT7475_VOLTAGE_COUNT   2
+#define ADT7475_VOLTAGE_COUNT   5       /* Not counting Vtt */
 #define ADT7475_TEMP_COUNT      3
 #define ADT7475_TACH_COUNT      4
 #define ADT7475_PWM_COUNT       3
@@ -137,8 +137,9 @@ struct adt7475_data {
 
         u8 config4;
         u8 config5;
+        u8 has_voltage;
         u16 alarms;
-        u16 voltage[3][3];
+        u16 voltage[3][6];
         u16 temp[7][3];
         u16 tach[2][4];
         u8 pwm[4][3];
@@ -201,26 +202,30 @@ static inline u16 rpm2tach(unsigned long rpm)
         return SENSORS_LIMIT((90000 * 60) / rpm, 1, 0xFFFF);
 }
 
-static inline int reg2vcc(u16 reg)
-{
-        return (4296 * reg) / 1000;
-}
+/* Scaling factors for voltage inputs, taken from the ADT7490 datasheet */
+static const int adt7473_in_scaling[ADT7475_VOLTAGE_COUNT + 1][2] = {
+        { 45, 94 },     /* +2.5V */
+        { 175, 525 },   /* Vccp */
+        { 68, 71 },     /* Vcc */
+        { 93, 47 },     /* +5V */
+        { 120, 20 },    /* +12V */
+        { 45, 45 },     /* Vtt */
+};
 
-static inline int reg2vccp(u16 reg)
+static inline int reg2volt(int channel, u16 reg)
 {
-        return (2929 * reg) / 1000;
-}
+        const int *r = adt7473_in_scaling[channel];
 
-static inline u16 vcc2reg(long vcc)
-{
-        vcc = SENSORS_LIMIT(vcc, 0, 4396);
-        return (vcc * 1000) / 4296;
+        return DIV_ROUND_CLOSEST(reg * (r[0] + r[1]) * 2250, r[1] * 1024);
 }
 
-static inline u16 vccp2reg(long vcc)
+static inline u16 volt2reg(int channel, long volt)
 {
-        vcc = SENSORS_LIMIT(vcc, 0, 2998);
-        return (vcc * 1000) / 2929;
+        const int *r = adt7473_in_scaling[channel];
+        long reg;
+
+        reg = (volt * r[1] * 1024) / ((r[0] + r[1]) * 2250);
+        return SENSORS_LIMIT(reg, 0, 1023) & (0xff << 2);
 }
 
 static u16 adt7475_read_word(struct i2c_client *client, int reg)
@@ -276,12 +281,10 @@ static ssize_t show_voltage(struct device *dev, struct device_attribute *attr,
         switch (sattr->nr) {
         case ALARM:
                 return sprintf(buf, "%d\n",
-                               (data->alarms >> (sattr->index + 1)) & 1);
+                               (data->alarms >> sattr->index) & 1);
         default:
                 val = data->voltage[sattr->nr][sattr->index];
-                return sprintf(buf, "%d\n",
-                               sattr->index ==
-                               0 ? reg2vccp(val) : reg2vcc(val));
+                return sprintf(buf, "%d\n", reg2volt(sattr->index, val));
         }
 }
 
@@ -300,8 +303,7 @@ static ssize_t set_voltage(struct device *dev, struct device_attribute *attr,
 
         mutex_lock(&data->lock);
 
-        data->voltage[sattr->nr][sattr->index] =
-                sattr->index ? vcc2reg(val) : vccp2reg(val);
+        data->voltage[sattr->nr][sattr->index] = volt2reg(sattr->index, val);
 
         if (sattr->nr == MIN)
                 reg = VOLTAGE_MIN_REG(sattr->index);
@@ -815,18 +817,18 @@ static ssize_t set_pwm_at_crit(struct device *dev,
         return count;
 }
 
-static SENSOR_DEVICE_ATTR_2(in1_input, S_IRUGO, show_voltage, NULL, INPUT, 0);
+static SENSOR_DEVICE_ATTR_2(in1_input, S_IRUGO, show_voltage, NULL, INPUT, 1);
 static SENSOR_DEVICE_ATTR_2(in1_max, S_IRUGO | S_IWUSR, show_voltage,
-                            set_voltage, MAX, 0);
+                            set_voltage, MAX, 1);
 static SENSOR_DEVICE_ATTR_2(in1_min, S_IRUGO | S_IWUSR, show_voltage,
-                            set_voltage, MIN, 0);
-static SENSOR_DEVICE_ATTR_2(in1_alarm, S_IRUGO, show_voltage, NULL, ALARM, 0);
-static SENSOR_DEVICE_ATTR_2(in2_input, S_IRUGO, show_voltage, NULL, INPUT, 1);
+                            set_voltage, MIN, 1);
+static SENSOR_DEVICE_ATTR_2(in1_alarm, S_IRUGO, show_voltage, NULL, ALARM, 1);
+static SENSOR_DEVICE_ATTR_2(in2_input, S_IRUGO, show_voltage, NULL, INPUT, 2);
 static SENSOR_DEVICE_ATTR_2(in2_max, S_IRUGO | S_IWUSR, show_voltage,
-                            set_voltage, MAX, 1);
+                            set_voltage, MAX, 2);
 static SENSOR_DEVICE_ATTR_2(in2_min, S_IRUGO | S_IWUSR, show_voltage,
-                            set_voltage, MIN, 1);
-static SENSOR_DEVICE_ATTR_2(in2_alarm, S_IRUGO, show_voltage, NULL, ALARM, 1);
+                            set_voltage, MIN, 2);
+static SENSOR_DEVICE_ATTR_2(in2_alarm, S_IRUGO, show_voltage, NULL, ALARM, 2);
 static SENSOR_DEVICE_ATTR_2(temp1_input, S_IRUGO, show_temp, NULL, INPUT, 0);
 static SENSOR_DEVICE_ATTR_2(temp1_alarm, S_IRUGO, show_temp, NULL, ALARM, 0);
 static SENSOR_DEVICE_ATTR_2(temp1_fault, S_IRUGO, show_temp, NULL, FAULT, 0);
@@ -1050,6 +1052,12 @@ static int adt7475_probe(struct i2c_client *client,
         mutex_init(&data->lock);
         i2c_set_clientdata(client, data);
 
+        /* Initialize device-specific values */
+        switch (id->driver_data) {
+        default:
+                data->has_voltage = 0x06;       /* in1, in2 */
+        }
+
         /* Call adt7475_read_pwm for all pwm's as this will reprogram any
            pwm's which are disabled to manual mode with 0% duty cycle */
         for (i = 0; i < ADT7475_PWM_COUNT; i++)
@@ -1176,10 +1184,13 @@ static struct adt7475_data *adt7475_update_device(struct device *dev)
                 data->alarms |= adt7475_read(REG_STATUS1);
 
                 ext = adt7475_read(REG_EXTEND1);
-                for (i = 0; i < ADT7475_VOLTAGE_COUNT; i++)
+                for (i = 0; i < ADT7475_VOLTAGE_COUNT; i++) {
+                        if (!(data->has_voltage & (1 << i)))
+                                continue;
                         data->voltage[INPUT][i] =
                                 (adt7475_read(VOLTAGE_REG(i)) << 2) |
-                                ((ext >> ((i + 1) * 2)) & 3);
+                                ((ext >> (i * 2)) & 3);
+                }
 
                 ext = adt7475_read(REG_EXTEND2);
                 for (i = 0; i < ADT7475_TEMP_COUNT; i++)
@@ -1205,6 +1216,8 @@ static struct adt7475_data *adt7475_update_device(struct device *dev)
                 data->config5 = adt7475_read(REG_CONFIG5);
 
                 for (i = 0; i < ADT7475_VOLTAGE_COUNT; i++) {
+                        if (!(data->has_voltage & (1 << i)))
+                                continue;
                         /* Adjust values so they match the input precision */
                         data->voltage[MIN][i] =
                                 adt7475_read(VOLTAGE_MIN_REG(i)) << 2;