hwmon: (adm1275) Add support for peak attributes

Add support for voltage and current peak (historic maximum) attributes.

Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
Reviewed-by: Robert Coulson <robert.coulson@ericsson.com>

2 files changed, 66 insertions, 2 deletions

diff --git a/Documentation/hwmon/adm1275 b/Documentation/hwmon/adm1275
index 6a3a6476cf2..097b3ccc4be 100644
--- a/Documentation/hwmon/adm1275
+++ b/Documentation/hwmon/adm1275
@@ -43,8 +43,8 @@ Documentation/hwmon/pmbus for details.
 Sysfs entries
 -------------
 
-The following attributes are supported. Limits are read-write; all other
-attributes are read-only.
+The following attributes are supported. Limits are read-write, history reset
+attributes are write-only, all other attributes are read-only.
 
 in1_label               "vin1" or "vout1" depending on chip variant and
                         configuration.
@@ -53,8 +53,12 @@ in1_min			Minumum Voltage. From VOUT_UV_WARN_LIMIT register.
 in1_max                 Maximum voltage. From VOUT_OV_WARN_LIMIT register.
 in1_min_alarm           Voltage low alarm. From VOLTAGE_UV_WARNING status.
 in1_max_alarm           Voltage high alarm. From VOLTAGE_OV_WARNING status.
+in1_highest             Historical maximum voltage.
+in1_reset_history       Write any value to reset history.
 
 curr1_label             "iout1"
 curr1_input             Measured current. From READ_IOUT register.
 curr1_max               Maximum current. From IOUT_OC_WARN_LIMIT register.
 curr1_max_alarm         Current high alarm. From IOUT_OC_WARN_LIMIT register.
+curr1_highest           Historical maximum current.
+curr1_reset_history     Write any value to reset history.
diff --git a/drivers/hwmon/pmbus/adm1275.c b/drivers/hwmon/pmbus/adm1275.c
index 71770ffbdaf..c936e278230 100644
--- a/drivers/hwmon/pmbus/adm1275.c
+++ b/drivers/hwmon/pmbus/adm1275.c
@@ -23,11 +23,68 @@
 #include <linux/i2c.h>
 #include "pmbus.h"
 
+#define ADM1275_PEAK_IOUT               0xd0
+#define ADM1275_PEAK_VIN                0xd1
+#define ADM1275_PEAK_VOUT               0xd2
 #define ADM1275_PMON_CONFIG             0xd4
 
 #define ADM1275_VIN_VOUT_SELECT         (1 << 6)
 #define ADM1275_VRANGE                  (1 << 5)
 
+static int adm1275_read_word_data(struct i2c_client *client, int page, int reg)
+{
+        int ret;
+
+        if (page)
+                return -EINVAL;
+
+        switch (reg) {
+        case PMBUS_VIRT_READ_IOUT_MAX:
+                ret = pmbus_read_word_data(client, 0, ADM1275_PEAK_IOUT);
+                break;
+        case PMBUS_VIRT_READ_VOUT_MAX:
+                ret = pmbus_read_word_data(client, 0, ADM1275_PEAK_VOUT);
+                break;
+        case PMBUS_VIRT_READ_VIN_MAX:
+                ret = pmbus_read_word_data(client, 0, ADM1275_PEAK_VIN);
+                break;
+        case PMBUS_VIRT_RESET_IOUT_HISTORY:
+        case PMBUS_VIRT_RESET_VOUT_HISTORY:
+        case PMBUS_VIRT_RESET_VIN_HISTORY:
+                ret = 0;
+                break;
+        default:
+                ret = -ENODATA;
+                break;
+        }
+        return ret;
+}
+
+static int adm1275_write_word_data(struct i2c_client *client, int page, int reg,
+                                   u16 word)
+{
+        int ret;
+
+        if (page)
+                return -EINVAL;
+
+        switch (reg) {
+        case PMBUS_VIRT_RESET_IOUT_HISTORY:
+                ret = pmbus_write_word_data(client, 0, ADM1275_PEAK_IOUT, 0);
+                break;
+        case PMBUS_VIRT_RESET_VOUT_HISTORY:
+                ret = pmbus_write_word_data(client, 0, ADM1275_PEAK_VOUT, 0);
+                break;
+        case PMBUS_VIRT_RESET_VIN_HISTORY:
+                ret = pmbus_write_word_data(client, 0, ADM1275_PEAK_VIN, 0);
+                break;
+        default:
+                ret = -ENODATA;
+                break;
+        }
+        return ret;
+}
+
 static int adm1275_probe(struct i2c_client *client,
                          const struct i2c_device_id *id)
 {
@@ -58,6 +115,9 @@ static int adm1275_probe(struct i2c_client *client,
         info->R[PSC_CURRENT_OUT] = -1;
         info->func[0] = PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT;
 
+        info->read_word_data = adm1275_read_word_data;
+        info->write_word_data = adm1275_write_word_data;
+
         if (config & ADM1275_VRANGE) {
                 info->m[PSC_VOLTAGE_IN] = 19199;
                 info->b[PSC_VOLTAGE_IN] = 0;