power: supply: cpcap-battery: Simplify short term power average calculation

We can use sign_extend32() here to simplify things. And let's fix the
comment for CCM register, that contains the calibration offset.

Cc: Merlijn Wajer <merlijn@wizzup.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

diff --git a/drivers/power/supply/cpcap-battery.c b/drivers/power/supply/cpcap-battery.c
index 5e5be42..cb4edb8 100644 (file)
--- a/drivers/power/supply/cpcap-battery.c
+++ b/drivers/power/supply/cpcap-battery.c
@@ -312,31 +312,28 @@ cpcap_battery_read_accumulated(struct cpcap_battery_ddata *ddata,
 static int cpcap_battery_cc_get_avg_current(struct cpcap_battery_ddata *ddata)
 {
        int value, acc, error;
-       s32 sample = 1;
+       s32 sample;
        s16 offset;
 
-       if (ddata->vendor == CPCAP_VENDOR_ST)
-               sample = 4;
-
        /* Coulomb counter integrator */
        error = regmap_read(ddata->reg, CPCAP_REG_CCI, &value);
        if (error)
                return error;
 
-       if ((ddata->vendor == CPCAP_VENDOR_TI) && (value > 0x2000))
-               value = value | 0xc000;
-
-       acc = (s16)value;
+       if (ddata->vendor == CPCAP_VENDOR_TI) {
+               acc = sign_extend32(value, 13);
+               sample = 1;
+       } else {
+               acc = (s16)value;
+               sample = 4;
+       }
 
-       /* Coulomb counter sample time */
+       /* Coulomb counter calibration offset  */
        error = regmap_read(ddata->reg, CPCAP_REG_CCM, &value);
        if (error)
                return error;
 
-       if (value < 0x200)
-               offset = value;
-       else
-               offset = value | 0xfc00;
+       offset = sign_extend32(value, 9);
 
        return cpcap_battery_cc_to_ua(ddata, sample, acc, offset);
 }