The ADC in the JZ4740 can work either in high-precision mode with a 2.5V
range, or in low-precision mode with a 7.5V range. The code in place in
this driver will select the proper scale according to the maximum
voltage of the battery.
The JZ4770 however only has one mode, with a 6.6V range. If only one
scale is available, there's no need to change it (and nothing to change
it to), and trying to do so will fail with -EINVAL.
Fixes: fb24ccfbe1e0 ("power: supply: add Ingenic JZ47xx battery driver.")
Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
---
Notes:
v2: Rebased on v5.4-rc7
v3: Move code after check for max scale voltage
drivers/power/supply/ingenic-battery.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)
diff --git a/drivers/power/supply/ingenic-battery.c b/drivers/power/supply/ingenic-battery.c
index 35816d4b3012..2748715c4c75 100644
--- a/drivers/power/supply/ingenic-battery.c
+++ b/drivers/power/supply/ingenic-battery.c
@@ -100,10 +100,17 @@ static int ingenic_battery_set_scale(struct ingenic_battery *bat)
return -EINVAL;
}
- return iio_write_channel_attribute(bat->channel,
- scale_raw[best_idx],
- scale_raw[best_idx + 1],
- IIO_CHAN_INFO_SCALE);
+ /* Only set scale if there is more than one (fractional) entry */
+ if (scale_len > 2) {
+ ret = iio_write_channel_attribute(bat->channel,
+ scale_raw[best_idx],
+ scale_raw[best_idx + 1],
+ IIO_CHAN_INFO_SCALE);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
}
static enum power_supply_property ingenic_battery_properties[] = {
--
2.24.0
