Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-27 06:31:52 +00:00
Code Issues Packages Projects Releases Wiki Activity

max8925_power: Fix incorrect voltage and current calculation

Browse Source 
The datasheet indicates a 12 bit value is returned for i2c
registers for voltage and current.  Code was assuming 8 bits.
But default for chip is 12 bit return value.

Voltage is returned in 2mV units  -- adjust to return as uV
per linux power spec

Adjust current calculation to return units in uA.

Signed-off-by: Philip Rakity <prakity@marvell.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
This commit is contained in:
Philip Rakity 2011-11-25 21:25:23 +04:00 committed by Anton Vorontsov
parent 44abd774f5
commit 9c9cf9e263
1 changed files with 6 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
drivers/power/max8925_power.c
View File

@ -188,7 +188,7 @@ static int start_measure(struct max8925_power_info *info, int type)
}
max8925_bulk_read(info->adc, meas_reg, 2, buf);
ret = (buf[0] << 4) | (buf[1] >> 4);
ret = ((buf[0]<<8) | buf[1]) >> 4;
return ret;
}
@ -208,7 +208,7 @@ static int max8925_ac_get_prop(struct power_supply *psy,
if (info->ac_online) {
ret = start_measure(info, MEASURE_VCHG);
if (ret >= 0) {
val->intval = ret << 1; /* unit is mV */
val->intval = ret * 2000; /* unit is uV */
goto out;
}
}
@ -242,7 +242,7 @@ static int max8925_usb_get_prop(struct power_supply *psy,
if (info->usb_online) {
ret = start_measure(info, MEASURE_VCHG);
if (ret >= 0) {
val->intval = ret << 1; /* unit is mV */
val->intval = ret * 2000; /* unit is uV */
goto out;
}
}
@ -266,7 +266,6 @@ static int max8925_bat_get_prop(struct power_supply *psy,
union power_supply_propval *val)
{
struct max8925_power_info *info = dev_get_drvdata(psy->dev->parent);
long long int tmp = 0;
int ret = 0;
switch (psp) {
@ -277,7 +276,7 @@ static int max8925_bat_get_prop(struct power_supply *psy,
if (info->bat_online) {
ret = start_measure(info, MEASURE_VMBATT);
if (ret >= 0) {
val->intval = ret << 1; /* unit is mV */
val->intval = ret * 2000; /* unit is uV */
ret = 0;
break;
}
@ -288,8 +287,8 @@ static int max8925_bat_get_prop(struct power_supply *psy,
if (info->bat_online) {
ret = start_measure(info, MEASURE_ISNS);
if (ret >= 0) {
tmp = (long long int)ret * 6250 / 4096 - 3125;
ret = (int)tmp;
/* assume r_sns is 0.02 */
ret = ((ret * 6250) - 3125) /* uA */;
val->intval = 0;
if (ret > 0)
val->intval = ret; /* unit is mA */