power: supply: cpcap-battery: Fix signed counter sample register

The accumulator sample register is signed 32-bits wide register on
droid 4. And only the earlier version of cpcap has a signed 24-bits
wide register. We're currently passing it around as unsigned, so
let's fix that and use sign_extend32() for the earlier revision.

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 d8855078dc1e9765804b5950d5afdd19a8d689f4..a9e4952e9c1270769fa85d5f78dcd5d032a58545 100644 (file)
--- a/drivers/power/supply/cpcap-battery.c
+++ b/drivers/power/supply/cpcap-battery.c
@@ -82,7 +82,7 @@ struct cpcap_battery_config {
 };
 
 struct cpcap_coulomb_counter_data {
-       s32 sample;             /* 24-bits */
+       s32 sample;             /* 24 or 32 bits */
        s32 accumulator;
        s16 offset;             /* 10-bits */
 };
@@ -213,7 +213,7 @@ static int cpcap_battery_get_current(struct cpcap_battery_ddata *ddata)
  * TI or ST coulomb counter in the PMIC.
  */
 static int cpcap_battery_cc_raw_div(struct cpcap_battery_ddata *ddata,
-                                   u32 sample, s32 accumulator,
+                                   s32 sample, s32 accumulator,
                                    s16 offset, u32 divider)
 {
        s64 acc;
@@ -224,7 +224,6 @@ static int cpcap_battery_cc_raw_div(struct cpcap_battery_ddata *ddata,
        if (!divider)
                return 0;
 
-       sample &= 0xffffff;             /* 24-bits, unsigned */
        offset &= 0x7ff;                /* 10-bits, signed */
 
        switch (ddata->vendor) {
@@ -259,7 +258,7 @@ static int cpcap_battery_cc_raw_div(struct cpcap_battery_ddata *ddata,
 
 /* 3600000μAms = 1μAh */
 static int cpcap_battery_cc_to_uah(struct cpcap_battery_ddata *ddata,
-                                  u32 sample, s32 accumulator,
+                                  s32 sample, s32 accumulator,
                                   s16 offset)
 {
        return cpcap_battery_cc_raw_div(ddata, sample,
@@ -268,7 +267,7 @@ static int cpcap_battery_cc_to_uah(struct cpcap_battery_ddata *ddata,
 }
 
 static int cpcap_battery_cc_to_ua(struct cpcap_battery_ddata *ddata,
-                                 u32 sample, s32 accumulator,
+                                 s32 sample, s32 accumulator,
                                  s16 offset)
 {
        return cpcap_battery_cc_raw_div(ddata, sample,
@@ -312,6 +311,8 @@ cpcap_battery_read_accumulated(struct cpcap_battery_ddata *ddata,
        /* Sample value CPCAP_REG_CCS1 & 2 */
        ccd->sample = (buf[1] & 0x0fff) << 16;
        ccd->sample |= buf[0];
+       if (ddata->vendor == CPCAP_VENDOR_TI)
+               ccd->sample = sign_extend32(24, ccd->sample);
 
        /* Accumulator value CPCAP_REG_CCA1 & 2 */
        ccd->accumulator = ((s16)buf[3]) << 16;