hwmon: ina230: enable current monitoring without resistor value

This patch adds support to current monitoring alert when resistor
value is not defined in the platform configuration (which is the
nominal case for most of the platforms).

Change-Id: I504a0d601713470f74853bada45c42806dd0febd
Signed-off-by: Timo Alho <talho@nvidia.com>
Reviewed-on: http://git-master/r/262563
Reviewed-by: Juha Tukkinen <jtukkinen@nvidia.com>

diff --git a/drivers/hwmon/ina230.c b/drivers/hwmon/ina230.c
index 373a4062ef11bd44ee0f3bc819dfd8173fb8f73d..65b94eeb70cd85075792b6bad388e5d4cc6b840b 100644 (file)
--- a/drivers/hwmon/ina230.c
+++ b/drivers/hwmon/ina230.c
@@ -206,7 +206,18 @@ static s32 __locked_start_current_mon(struct i2c_client *client)
                return retval;
        }
 
-       shunt_uV = data->pdata->resistor * data->pdata->current_threshold;
+       if (data->pdata->resistor) {
+               shunt_uV = data->pdata->resistor;
+               shunt_uV *= data->pdata->current_threshold;
+       } else {
+               s32 v;
+               /* no resistor value defined, compute shunt_uV the hard way */
+               v = data->pdata->precision_multiplier * 5120 * 25;
+               v /= data->pdata->calibration_data;
+               v *= data->pdata->current_threshold;
+               v /= data->pdata->power_lsb;
+               shunt_uV = (s16)(v & 0xffff);
+       }
        if (data->pdata->shunt_polarity_inverted)
                shunt_uV *= -1;