Re: [PATCH v2 15/17] power: axp20x_battery: Add constant charge current table

Aidan MacDonald
2022-06-10T15:42:41Z

Sebastian Reichel <sebastian.reichel@collabora.com> writes:

> Hi,
>
> On Tue, Jun 07, 2022 at 04:53:22PM +0100, Aidan MacDonald wrote:
>> Add a table-based lookup method for constant charge current,
>> which is necessary when the setting cannot be represented as
>> a linear range.
>>
>> Signed-off-by: Aidan MacDonald <aidanmacdonald.0x0@gmail.com>
>> ---
>> drivers/power/supply/axp20x_battery.c | 53 +++++++++++++++++++++------
>> 1 file changed, 41 insertions(+), 12 deletions(-)
>>
>> diff --git a/drivers/power/supply/axp20x_battery.c b/drivers/power/supply/axp20x_battery.c
>> index 9106077c0dbb..87fb958f2224 100644
>> --- a/drivers/power/supply/axp20x_battery.c
>> +++ b/drivers/power/supply/axp20x_battery.c
>> @@ -61,6 +61,7 @@ struct axp20x_batt_ps;
>> struct axp_data {
>> int ccc_scale;
>> int ccc_offset;
>> + const int *ccc_table;
>
> Please document the struct; especially the fact that ccc_table must
> have a size of AXP20X_CHRG_CTRL1_TGT_CURR + 1.
>
> -- Sebastian
>

Thanks, I'll make sure to do that in v3.

Regards,
Aidan

>> bool has_fg_valid;
>> int (*get_max_voltage)(struct axp20x_batt_ps *batt, int *val);
>> int (*set_max_voltage)(struct axp20x_batt_ps *batt, int val);
>> @@ -176,7 +177,10 @@ static int axp20x_get_constant_charge_current(struct axp20x_batt_ps *axp,
>>
>> *val &= AXP20X_CHRG_CTRL1_TGT_CURR;
>>
>> - *val = *val * axp->data->ccc_scale + axp->data->ccc_offset;
>> + if (axp->data->ccc_table)
>> + *val = axp->data->ccc_table[*val];
>> + else
>> + *val = *val * axp->data->ccc_scale + axp->data->ccc_offset;
>>
>> return 0;
>> }
>> @@ -389,16 +393,36 @@ static int axp20x_battery_set_max_voltage(struct axp20x_batt_ps *axp20x_batt,
>> AXP20X_CHRG_CTRL1_TGT_VOLT, val);
>> }
>>
>> +static int axp20x_get_constant_charge_current_sel(struct axp20x_batt_ps *axp_batt,
>> + int charge_current)
>> +{
>> + int i;
>> +
>> + if (axp_batt->data->ccc_table) {
>> + for (i = AXP20X_CHRG_CTRL1_TGT_CURR; i >= 0; --i) {
>> + if (axp_batt->data->ccc_table[i] <= charge_current)
>> + return i;
>> + }
>> +
>> + return -EINVAL;
>> + }
>> +
>> + i = (charge_current - axp_batt->data->ccc_offset) / axp_batt->data->ccc_scale;
>> +
>> + if (i > AXP20X_CHRG_CTRL1_TGT_CURR || i < 0)
>> + return -EINVAL;
>> +
>> + return i;
>> +}
>> +
>> static int axp20x_set_constant_charge_current(struct axp20x_batt_ps *axp_batt,
>> int charge_current)
>> {
>> if (charge_current > axp_batt->max_ccc)
>> return -EINVAL;
>>
>> - charge_current = (charge_current - axp_batt->data->ccc_offset) /
>> - axp_batt->data->ccc_scale;
>> -
>> - if (charge_current > AXP20X_CHRG_CTRL1_TGT_CURR || charge_current < 0)
>> + charge_current = axp20x_get_constant_charge_current_sel(axp_batt, charge_current);
>> + if (charge_current < 0)
>> return -EINVAL;
>>
>> return regmap_update_bits(axp_batt->regmap, AXP20X_CHRG_CTRL1,
>> @@ -410,14 +434,14 @@ static int axp20x_set_max_constant_charge_current(struct axp20x_batt_ps *axp,
>> {
>> bool lower_max = false;
>>
>> - charge_current = (charge_current - axp->data->ccc_offset) /
>> - axp->data->ccc_scale;
>> -
>> - if (charge_current > AXP20X_CHRG_CTRL1_TGT_CURR || charge_current < 0)
>> + charge_current = axp20x_get_constant_charge_current_sel(axp, charge_current);
>> + if (charge_current < 0)
>> return -EINVAL;
>>
>> - charge_current = charge_current * axp->data->ccc_scale +
>> - axp->data->ccc_offset;
>> + if (axp->data->ccc_table)
>> + charge_current = axp->data->ccc_table[charge_current];
>> + else
>> + charge_current = charge_current * axp->data->ccc_scale + axp->data->ccc_offset;
>>
>> if (charge_current > axp->max_ccc)
>> dev_warn(axp->dev,
>> @@ -629,7 +653,12 @@ static int axp20x_power_probe(struct platform_device *pdev)
>> ccc)) {
>> dev_err(&pdev->dev,
>> "couldn't set constant charge current from DT: fallback to minimum value\n");
>> - ccc = 300000;
>> +
>> + if (axp20x_batt->data->ccc_table)
>> + ccc = axp20x_batt->data->ccc_table[0];
>> + else
>> + ccc = axp20x_batt->data->ccc_offset;
>> +
>> axp20x_batt->max_ccc = ccc;
>> axp20x_set_constant_charge_current(axp20x_batt, ccc);
>> }
>> --
>> 2.35.1
>>