2019-11-14 16:37:12

by Paul Cercueil

Subject: [PATCH v2] power/supply: ingenic-battery: Don't change scale if there's only one

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 <[email protected]>
Cc: [email protected]
---

Notes:
v2: Rebased on v5.4-rc7

drivers/power/supply/ingenic-battery.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/power/supply/ingenic-battery.c b/drivers/power/supply/ingenic-battery.c
index 35816d4b3012..5a53057b4f64 100644
--- a/drivers/power/supply/ingenic-battery.c
+++ b/drivers/power/supply/ingenic-battery.c
@@ -80,6 +80,10 @@ static int ingenic_battery_set_scale(struct ingenic_battery *bat)
if (ret != IIO_AVAIL_LIST || scale_type != IIO_VAL_FRACTIONAL_LOG2)
return -EINVAL;

+ /* Only one (fractional) entry - nothing to change */
+ if (scale_len == 2)
+ return 0;
+
max_mV = bat->info.voltage_max_design_uv / 1000;

for (i = 0; i < scale_len; i += 2) {
--
2.24.0

2019-11-15 17:42:54

by Artur Rojek

Subject: Re: [PATCH v2] power/supply: ingenic-battery: Don't change scale if there's only one

Hi Paul.
Comments inline.

On 2019-11-14 17:35, Paul Cercueil wrote:
> 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 <[email protected]>
> Cc: [email protected]
> ---
>
> Notes:
> v2: Rebased on v5.4-rc7
>
> drivers/power/supply/ingenic-battery.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/drivers/power/supply/ingenic-battery.c
> b/drivers/power/supply/ingenic-battery.c
> index 35816d4b3012..5a53057b4f64 100644
> --- a/drivers/power/supply/ingenic-battery.c
> +++ b/drivers/power/supply/ingenic-battery.c
> @@ -80,6 +80,10 @@ static int ingenic_battery_set_scale(struct
> ingenic_battery *bat)
> if (ret != IIO_AVAIL_LIST || scale_type != IIO_VAL_FRACTIONAL_LOG2)
> return -EINVAL;
>
> + /* Only one (fractional) entry - nothing to change */
> + if (scale_len == 2)
> + return 0;
> +

This function also serves to validate that the maximum voltage is in
range of available scales.
Please move your code down a bit so that the check for max_mV is still
being done.

Thanks,
Artur

> max_mV = bat->info.voltage_max_design_uv / 1000;
>
> for (i = 0; i < scale_len; i += 2) {

2019-11-16 13:57:55

by Paul Cercueil

Subject: Re: [PATCH v2] power/supply: ingenic-battery: Don't change scale if there's only one

Hi Artur,


Le ven., nov. 15, 2019 at 18:39, Artur Rojek <[email protected]> a
?crit :
> Hi Paul.
> Comments inline.
>
> On 2019-11-14 17:35, Paul Cercueil wrote:
>> 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 <[email protected]>
>> Cc: [email protected]
>> ---
>>
>> Notes:
>> v2: Rebased on v5.4-rc7
>>
>> drivers/power/supply/ingenic-battery.c | 4 ++++
>> 1 file changed, 4 insertions(+)
>>
>> diff --git a/drivers/power/supply/ingenic-battery.c
>> b/drivers/power/supply/ingenic-battery.c
>> index 35816d4b3012..5a53057b4f64 100644
>> --- a/drivers/power/supply/ingenic-battery.c
>> +++ b/drivers/power/supply/ingenic-battery.c
>> @@ -80,6 +80,10 @@ static int ingenic_battery_set_scale(struct
>> ingenic_battery *bat)
>> if (ret != IIO_AVAIL_LIST || scale_type != IIO_VAL_FRACTIONAL_LOG2)
>> return -EINVAL;
>>
>> + /* Only one (fractional) entry - nothing to change */
>> + if (scale_len == 2)
>> + return 0;
>> +
>
> This function also serves to validate that the maximum voltage is in
> range of available scales.
> Please move your code down a bit so that the check for max_mV is
> still being done.

Good point - I'll send a V3.

-Paul

>
> Thanks,
> Artur
>
>> max_mV = bat->info.voltage_max_design_uv / 1000;
>>
>> for (i = 0; i < scale_len; i += 2) {