hwmon: (ina2xx) Use structure array to distinguish chip types

Replace per-device initialization and per-device calculation code with
per-device configuration data, which is then used to configure the chip and
perform calculations based on that data.

This patch reduces code size by more than 400 bytes on x86_64.

Cc: Lothar Felten <l-felten@ti.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Jean Delvare <khali@linux-fr.org>

1 files changed, 56 insertions, 103 deletions

diff --git a/drivers/hwmon/ina2xx.c b/drivers/hwmon/ina2xx.c
index 602148299f6..de8f2c6c6b6 100644
--- a/drivers/hwmon/ina2xx.c
+++ b/drivers/hwmon/ina2xx.c
@@ -57,18 +57,49 @@
 
 enum ina2xx_ids { ina219, ina226 };
 
+struct ina2xx_config {
+        u16 config_default;
+        int calibration_factor;
+        int registers;
+        int shunt_div;
+        int bus_voltage_shift;
+        int bus_voltage_lsb;    /* uV */
+        int power_lsb;          /* uW */
+};
+
 struct ina2xx_data {
         struct device *hwmon_dev;
+        const struct ina2xx_config *config;
 
         struct mutex update_lock;
         bool valid;
         unsigned long last_updated;
 
         int kind;
-        int registers;
         u16 regs[INA2XX_MAX_REGISTERS];
 };
 
+static const struct ina2xx_config ina2xx_config[] = {
+        [ina219] = {
+                .config_default = INA219_CONFIG_DEFAULT,
+                .calibration_factor = 40960000,
+                .registers = INA219_REGISTERS,
+                .shunt_div = 100,
+                .bus_voltage_shift = 3,
+                .bus_voltage_lsb = 4000,
+                .power_lsb = 20000,
+        },
+        [ina226] = {
+                .config_default = INA226_CONFIG_DEFAULT,
+                .calibration_factor = 5120000,
+                .registers = INA226_REGISTERS,
+                .shunt_div = 400,
+                .bus_voltage_shift = 0,
+                .bus_voltage_lsb = 1250,
+                .power_lsb = 25000,
+        },
+};
+
 static struct ina2xx_data *ina2xx_update_device(struct device *dev)
 {
         struct i2c_client *client = to_i2c_client(dev);
@@ -85,7 +116,7 @@ static struct ina2xx_data *ina2xx_update_device(struct device *dev)
                 dev_dbg(&client->dev, "Starting ina2xx update\n");
 
                 /* Read all registers */
-                for (i = 0; i < data->registers; i++) {
+                for (i = 0; i < data->config->registers; i++) {
                         int rv = i2c_smbus_read_word_swapped(client, i);
                         if (rv < 0) {
                                 ret = ERR_PTR(rv);
@@ -101,73 +132,26 @@ abort:
         return ret;
 }
 
-static int ina219_get_value(struct ina2xx_data *data, u8 reg)
-{
-        /*
-         * calculate exact value for the given register
-         * we assume default power-on reset settings:
-         * bus voltage range 32V
-         * gain = /8
-         * adc 1 & 2 -> conversion time 532uS
-         * mode is continuous shunt and bus
-         * calibration value is INA219_CALIBRATION_VALUE
-         */
-        int val = data->regs[reg];
-
-        switch (reg) {
-        case INA2XX_SHUNT_VOLTAGE:
-                /* LSB=10uV. Convert to mV. */
-                val = DIV_ROUND_CLOSEST(val, 100);
-                break;
-        case INA2XX_BUS_VOLTAGE:
-                /* LSB=4mV. Register is not right aligned, convert to mV. */
-                val = (val >> 3) * 4;
-                break;
-        case INA2XX_POWER:
-                /* LSB=20mW. Convert to uW */
-                val = val * 20 * 1000;
-                break;
-        case INA2XX_CURRENT:
-                /* LSB=1mA (selected). Is in mA */
-                break;
-        default:
-                /* programmer goofed */
-                WARN_ON_ONCE(1);
-                val = 0;
-                break;
-        }
-
-        return val;
-}
-
-static int ina226_get_value(struct ina2xx_data *data, u8 reg)
+static int ina2xx_get_value(struct ina2xx_data *data, u8 reg)
 {
-        /*
-         * calculate exact value for the given register
-         * we assume default power-on reset settings:
-         * bus voltage range 32V
-         * gain = /8
-         * adc 1 & 2 -> conversion time 532uS
-         * mode is continuous shunt and bus
-         * calibration value is INA226_CALIBRATION_VALUE
-         */
-        int val = data->regs[reg];
+        int val;
 
         switch (reg) {
         case INA2XX_SHUNT_VOLTAGE:
-                /* LSB=2.5uV. Convert to mV. */
-                val = DIV_ROUND_CLOSEST(val, 400);
+                val = DIV_ROUND_CLOSEST(data->regs[reg],
+                                        data->config->shunt_div);
                 break;
         case INA2XX_BUS_VOLTAGE:
-                /* LSB=1.25mV. Convert to mV. */
-                val = val + DIV_ROUND_CLOSEST(val, 4);
+                val = (data->regs[reg] >> data->config->bus_voltage_shift)
+                  * data->config->bus_voltage_lsb;
+                val = DIV_ROUND_CLOSEST(val, 1000);
                 break;
         case INA2XX_POWER:
-                /* LSB=25mW. Convert to uW */
-                val = val * 25 * 1000;
+                val = data->regs[reg] * data->config->power_lsb;
                 break;
         case INA2XX_CURRENT:
                 /* LSB=1mA (selected). Is in mA */
+                val = data->regs[reg];
                 break;
         default:
                 /* programmer goofed */
@@ -184,23 +168,12 @@ static ssize_t ina2xx_show_value(struct device *dev,
 {
         struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
         struct ina2xx_data *data = ina2xx_update_device(dev);
-        int value = 0;
 
         if (IS_ERR(data))
                 return PTR_ERR(data);
 
-        switch (data->kind) {
-        case ina219:
-                value = ina219_get_value(data, attr->index);
-                break;
-        case ina226:
-                value = ina226_get_value(data, attr->index);
-                break;
-        default:
-                WARN_ON_ONCE(1);
-                break;
-        }
-        return snprintf(buf, PAGE_SIZE, "%d\n", value);
+        return snprintf(buf, PAGE_SIZE, "%d\n",
+                        ina2xx_get_value(data, attr->index));
 }
 
 /* shunt voltage */
@@ -238,7 +211,7 @@ static int ina2xx_probe(struct i2c_client *client,
         struct i2c_adapter *adapter = client->adapter;
         struct ina2xx_data *data;
         struct ina2xx_platform_data *pdata;
-        int ret = 0;
+        int ret;
         long shunt = 10000; /* default shunt value 10mOhms */
 
         if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA))
@@ -259,38 +232,15 @@ static int ina2xx_probe(struct i2c_client *client,
 
         /* set the device type */
         data->kind = id->driver_data;
+        data->config = &ina2xx_config[data->kind];
 
-        switch (data->kind) {
-        case ina219:
-                /* device configuration */
-                i2c_smbus_write_word_swapped(client, INA2XX_CONFIG,
-                                             INA219_CONFIG_DEFAULT);
-
-                /* set current LSB to 1mA, shunt is in uOhms */
-                /* (equation 13 in datasheet) */
-                i2c_smbus_write_word_swapped(client, INA2XX_CALIBRATION,
-                                             40960000 / shunt);
-                dev_info(&client->dev,
-                         "power monitor INA219 (Rshunt = %li uOhm)\n", shunt);
-                data->registers = INA219_REGISTERS;
-                break;
-        case ina226:
-                /* device configuration */
-                i2c_smbus_write_word_swapped(client, INA2XX_CONFIG,
-                                             INA226_CONFIG_DEFAULT);
-
-                /* set current LSB to 1mA, shunt is in uOhms */
-                /* (equation 1 in datasheet)*/
-                i2c_smbus_write_word_swapped(client, INA2XX_CALIBRATION,
-                                             5120000 / shunt);
-                dev_info(&client->dev,
-                         "power monitor INA226 (Rshunt = %li uOhm)\n", shunt);
-                data->registers = INA226_REGISTERS;
-                break;
-        default:
-                /* unknown device id */
-                return -ENODEV;
-        }
+        /* device configuration */
+        i2c_smbus_write_word_swapped(client, INA2XX_CONFIG,
+                                     data->config->config_default);
+        /* set current LSB to 1mA, shunt is in uOhms */
+        /* (equation 13 in datasheet) */
+        i2c_smbus_write_word_swapped(client, INA2XX_CALIBRATION,
+                                     data->config->calibration_factor / shunt);
 
         i2c_set_clientdata(client, data);
         mutex_init(&data->update_lock);
@@ -305,6 +255,9 @@ static int ina2xx_probe(struct i2c_client *client,
                 goto out_err_hwmon;
         }
 
+        dev_info(&client->dev, "power monitor %s (Rshunt = %li uOhm)\n",
+                 id->name, shunt);
+
         return 0;
 
 out_err_hwmon: