hwmon: (mp2925) Add vid offset for vid mode

In vid mode, the mp2925 vout telemetry has 49 vid step offset, add
vid offset for this.

Signed-off-by: Wensheng Wang <wenswang@yeah.net>
Link: https://lore.kernel.org/r/20260106061348.170509-1-wenswang@yeah.net
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

diff --git a/drivers/hwmon/pmbus/mp2925.c b/drivers/hwmon/pmbus/mp2925.c
index 6bebd60230219941b8961173abfb3742c6eaa326..ad094842cf2d737bea1a815f6f8f1953c984ed98 100644 (file)
--- a/drivers/hwmon/pmbus/mp2925.c
+++ b/drivers/hwmon/pmbus/mp2925.c
@@ -40,6 +40,7 @@
 struct mp2925_data {
        struct pmbus_driver_info info;
        int vout_scale[MP2925_PAGE_NUM];
+       int vid_offset[MP2925_PAGE_NUM];
 };
 
 #define to_mp2925_data(x) container_of(x, struct mp2925_data, info)
@@ -94,8 +95,15 @@ static int mp2925_read_word_data(struct i2c_client *client, int page, int phase,
                if (ret < 0)
                        return ret;
 
-               ret = DIV_ROUND_CLOSEST((ret & GENMASK(11, 0)) * data->vout_scale[page],
-                                       MP2925_VOUT_DIV);
+               /*
+                * In vid mode, the MP2925 vout telemetry has 49 vid step offset, but
+                * PMBUS_VOUT_OV_FAULT_LIMIT and PMBUS_VOUT_UV_FAULT_LIMIT do not take
+                * this into consideration, its resolution is 1.95mV/LSB, as a result,
+                * format[PSC_VOLTAGE_OUT] can not be set to vid directly. Adding extra
+                * vid_offset variable for vout telemetry.
+                */
+               ret = DIV_ROUND_CLOSEST(((ret & GENMASK(11, 0)) + data->vid_offset[page]) *
+                                       data->vout_scale[page], MP2925_VOUT_DIV);
                break;
        case PMBUS_VOUT_OV_FAULT_LIMIT:
        case PMBUS_VOUT_UV_FAULT_LIMIT:
@@ -231,10 +239,21 @@ mp2925_identify_vout_scale(struct i2c_client *client, struct pmbus_driver_info *
                        data->vout_scale[page] = 2560;
                else
                        data->vout_scale[page] = 5120;
+
+               /*
+                * In vid mode, the MP2925 vout telemetry has 49 vid step offset, but
+                * PMBUS_VOUT_OV_FAULT_LIMIT and PMBUS_VOUT_UV_FAULT_LIMIT do not take
+                * this into consideration, its resolution is 1.95mV/LSB, as a result,
+                * format[PSC_VOLTAGE_OUT] can not be set to vid directly. Adding extra
+                * vid_offset variable for vout telemetry.
+                */
+               data->vid_offset[page] = 49;
        } else if (FIELD_GET(GENMASK(4, 4), ret)) {
                data->vout_scale[page] = 1;
+               data->vid_offset[page] = 0;
        } else {
                data->vout_scale[page] = 512;
+               data->vid_offset[page] = 0;
        }
 
        return 0;