hwmon: (pmbus/adm1275) Fix power sampling support

Not every chip supported by this driver supports setting the number
of samples for power averaging. Also, the power monitoring register
is not always a 16-bit register, and the configuration bits used for
voltage sampling are different depending on the register width.
Some conditional code is needed to fix the problem.

On top of all that, the compiler complains about problems with
FIELD_GET and FIELD_PREP macros if the file is built with W=1.
Avoid using those macros to silence the warning.

Cc: Krzysztof Adamski <krzysztof.adamski@nokia.com>
Cc: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Reviewed-by: Krzysztof Adamski <krzysztof.adamski@nokia.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

diff --git a/drivers/hwmon/pmbus/adm1275.c b/drivers/hwmon/pmbus/adm1275.c
index a477ce0..5caa37f 100644 (file)
--- a/drivers/hwmon/pmbus/adm1275.c
+++ b/drivers/hwmon/pmbus/adm1275.c
@@ -71,9 +71,17 @@ enum chips { adm1075, adm1272, adm1275, adm1276, adm1278, adm1293, adm1294 };
 #define ADM1075_VAUX_OV_WARN           BIT(7)
 #define ADM1075_VAUX_UV_WARN           BIT(6)
 
-#define ADM1275_PWR_AVG_MASK           GENMASK(13, 11)
-#define ADM1275_VI_AVG_MASK            GENMASK(10, 8)
-#define ADM1275_SAMPLES_AVG_MAX        128
+#define ADM1275_VI_AVG_SHIFT           0
+#define ADM1275_VI_AVG_MASK            GENMASK(ADM1275_VI_AVG_SHIFT + 2, \
+                                               ADM1275_VI_AVG_SHIFT)
+#define ADM1275_SAMPLES_AVG_MAX                128
+
+#define ADM1278_PWR_AVG_SHIFT          11
+#define ADM1278_PWR_AVG_MASK           GENMASK(ADM1278_PWR_AVG_SHIFT + 2, \
+                                               ADM1278_PWR_AVG_SHIFT)
+#define ADM1278_VI_AVG_SHIFT           8
+#define ADM1278_VI_AVG_MASK            GENMASK(ADM1278_VI_AVG_SHIFT + 2, \
+                                               ADM1278_VI_AVG_SHIFT)
 
 struct adm1275_data {
        int id;
@@ -86,6 +94,7 @@ struct adm1275_data {
        bool have_pin_min;
        bool have_pin_max;
        bool have_temp_max;
+       bool have_power_sampling;
        struct pmbus_driver_info info;
 };
 
@@ -161,28 +170,58 @@ static const struct coefficients adm1293_coefficients[] = {
        [18] = { 7658, 0, -3 },         /* power, 21V, irange200 */
 };
 
-static inline int adm1275_read_pmon_config(struct i2c_client *client, u16 mask)
+static int adm1275_read_pmon_config(const struct adm1275_data *data,
+                                   struct i2c_client *client, bool is_power)
 {
-       int ret;
-
-       ret = i2c_smbus_read_word_data(client, ADM1275_PMON_CONFIG);
+       int shift, ret;
+       u16 mask;
+
+       /*
+        * The PMON configuration register is a 16-bit register only on chips
+        * supporting power average sampling. On other chips it is an 8-bit
+        * register.
+        */
+       if (data->have_power_sampling) {
+               ret = i2c_smbus_read_word_data(client, ADM1275_PMON_CONFIG);
+               mask = is_power ? ADM1278_PWR_AVG_MASK : ADM1278_VI_AVG_MASK;
+               shift = is_power ? ADM1278_PWR_AVG_SHIFT : ADM1278_VI_AVG_SHIFT;
+       } else {
+               ret = i2c_smbus_read_byte_data(client, ADM1275_PMON_CONFIG);
+               mask = ADM1275_VI_AVG_MASK;
+               shift = ADM1275_VI_AVG_SHIFT;
+       }
        if (ret < 0)
                return ret;
 
-       return FIELD_GET(mask, (u16)ret);
+       return (ret & mask) >> shift;
 }
 
-static inline int adm1275_write_pmon_config(struct i2c_client *client, u16 mask,
-                                           u16 word)
+static int adm1275_write_pmon_config(const struct adm1275_data *data,
+                                    struct i2c_client *client,
+                                    bool is_power, u16 word)
 {
-       int ret;
-
-       ret = i2c_smbus_read_word_data(client, ADM1275_PMON_CONFIG);
+       int shift, ret;
+       u16 mask;
+
+       if (data->have_power_sampling) {
+               ret = i2c_smbus_read_word_data(client, ADM1275_PMON_CONFIG);
+               mask = is_power ? ADM1278_PWR_AVG_MASK : ADM1278_VI_AVG_MASK;
+               shift = is_power ? ADM1278_PWR_AVG_SHIFT : ADM1278_VI_AVG_SHIFT;
+       } else {
+               ret = i2c_smbus_read_byte_data(client, ADM1275_PMON_CONFIG);
+               mask = ADM1275_VI_AVG_MASK;
+               shift = ADM1275_VI_AVG_SHIFT;
+       }
        if (ret < 0)
                return ret;
 
-       word = FIELD_PREP(mask, word) | (ret & ~mask);
-       ret = i2c_smbus_write_word_data(client, ADM1275_PMON_CONFIG, word);
+       word = (ret & ~mask) | ((word << shift) & mask);
+       if (data->have_power_sampling)
+               ret = i2c_smbus_write_word_data(client, ADM1275_PMON_CONFIG,
+                                               word);
+       else
+               ret = i2c_smbus_write_byte_data(client, ADM1275_PMON_CONFIG,
+                                               word);
 
        return ret;
 }
@@ -266,14 +305,16 @@ static int adm1275_read_word_data(struct i2c_client *client, int page, int reg)
                        return -ENXIO;
                break;
        case PMBUS_VIRT_POWER_SAMPLES:
-               ret = adm1275_read_pmon_config(client, ADM1275_PWR_AVG_MASK);
+               if (!data->have_power_sampling)
+                       return -ENXIO;
+               ret = adm1275_read_pmon_config(data, client, true);
                if (ret < 0)
                        break;
                ret = BIT(ret);
                break;
        case PMBUS_VIRT_IN_SAMPLES:
        case PMBUS_VIRT_CURR_SAMPLES:
-               ret = adm1275_read_pmon_config(client, ADM1275_VI_AVG_MASK);
+               ret = adm1275_read_pmon_config(data, client, false);
                if (ret < 0)
                        break;
                ret = BIT(ret);
@@ -323,14 +364,16 @@ static int adm1275_write_word_data(struct i2c_client *client, int page, int reg,
                ret = pmbus_write_word_data(client, 0, ADM1278_PEAK_TEMP, 0);
                break;
        case PMBUS_VIRT_POWER_SAMPLES:
+               if (!data->have_power_sampling)
+                       return -ENXIO;
                word = clamp_val(word, 1, ADM1275_SAMPLES_AVG_MAX);
-               ret = adm1275_write_pmon_config(client, ADM1275_PWR_AVG_MASK,
+               ret = adm1275_write_pmon_config(data, client, true,
                                                ilog2(word));
                break;
        case PMBUS_VIRT_IN_SAMPLES:
        case PMBUS_VIRT_CURR_SAMPLES:
                word = clamp_val(word, 1, ADM1275_SAMPLES_AVG_MAX);
-               ret = adm1275_write_pmon_config(client, ADM1275_VI_AVG_MASK,
+               ret = adm1275_write_pmon_config(data, client, false,
                                                ilog2(word));
                break;
        default:
@@ -528,6 +571,7 @@ static int adm1275_probe(struct i2c_client *client,
                data->have_vout = true;
                data->have_pin_max = true;
                data->have_temp_max = true;
+               data->have_power_sampling = true;
 
                coefficients = adm1272_coefficients;
                vindex = (config & ADM1275_VRANGE) ? 1 : 0;
@@ -613,6 +657,7 @@ static int adm1275_probe(struct i2c_client *client,
                data->have_vout = true;
                data->have_pin_max = true;
                data->have_temp_max = true;
+               data->have_power_sampling = true;
 
                coefficients = adm1278_coefficients;
                vindex = 0;
@@ -648,6 +693,7 @@ static int adm1275_probe(struct i2c_client *client,
                data->have_pin_min = true;
                data->have_pin_max = true;
                data->have_mfr_vaux_status = true;
+               data->have_power_sampling = true;
 
                coefficients = adm1293_coefficients;