[PATCH v1 1/5] power: supply: axp20x_usb_power: Simplify USB current limit handling

From: Aidan MacDonald
Date: Sat Feb 18 2023 - 15:50:01 EST

Handle the USB current limit with a lookup table and regmap field,
which minimizes code duplication. Invalid or unlimited values are
denoted by -1 entries, and can't be selected from userspace.

Signed-off-by: Aidan MacDonald <aidanmacdonald.0x0@xxxxxxxxx>
---
drivers/power/supply/axp20x_usb_power.c | 172 ++++++++----------------
1 file changed, 57 insertions(+), 115 deletions(-)

diff --git a/drivers/power/supply/axp20x_usb_power.c b/drivers/power/supply/axp20x_usb_power.c
index a1e6d1d44808..67998fba702a 100644
--- a/drivers/power/supply/axp20x_usb_power.c
+++ b/drivers/power/supply/axp20x_usb_power.c
@@ -37,16 +37,6 @@
#define AXP20X_VBUS_VHOLD_uV(b) (4000000 + (((b) >> 3) & 7) * 100000)
#define AXP20X_VBUS_VHOLD_MASK GENMASK(5, 3)
#define AXP20X_VBUS_VHOLD_OFFSET 3
-#define AXP20X_VBUS_CLIMIT_MASK 3
-#define AXP20X_VBUS_CLIMIT_900mA 0
-#define AXP20X_VBUS_CLIMIT_500mA 1
-#define AXP20X_VBUS_CLIMIT_100mA 2
-#define AXP20X_VBUS_CLIMIT_NONE 3
-
-#define AXP813_VBUS_CLIMIT_900mA 0
-#define AXP813_VBUS_CLIMIT_1500mA 1
-#define AXP813_VBUS_CLIMIT_2000mA 2
-#define AXP813_VBUS_CLIMIT_2500mA 3

#define AXP20X_ADC_EN1_VBUS_CURR BIT(2)
#define AXP20X_ADC_EN1_VBUS_VOLT BIT(3)
@@ -61,10 +51,21 @@
*/
#define DEBOUNCE_TIME msecs_to_jiffies(50)

+struct axp_data {
+ const struct power_supply_desc *power_desc;
+ const char * const *irq_names;
+ unsigned int num_irq_names;
+ enum axp20x_variants axp20x_id;
+ const int *curr_lim_table;
+ struct reg_field curr_lim_fld;
+};
+
struct axp20x_usb_power {
struct regmap *regmap;
+ struct regmap_field *curr_lim_fld;
struct power_supply *supply;
enum axp20x_variants axp20x_id;
+ const struct axp_data *axp_data;
struct iio_channel *vbus_v;
struct iio_channel *vbus_i;
struct delayed_work vbus_detect;
@@ -121,60 +122,6 @@ static void axp20x_usb_power_poll_vbus(struct work_struct *work)
mod_delayed_work(system_power_efficient_wq, &power->vbus_detect, DEBOUNCE_TIME);
}

-static int axp20x_get_current_max(struct axp20x_usb_power *power, int *val)
-{
- unsigned int v;
- int ret = regmap_read(power->regmap, AXP20X_VBUS_IPSOUT_MGMT, &v);
-
- if (ret)
- return ret;
-
- switch (v & AXP20X_VBUS_CLIMIT_MASK) {
- case AXP20X_VBUS_CLIMIT_100mA:
- if (power->axp20x_id == AXP221_ID)
- *val = -1; /* No 100mA limit */
- else
- *val = 100000;
- break;
- case AXP20X_VBUS_CLIMIT_500mA:
- *val = 500000;
- break;
- case AXP20X_VBUS_CLIMIT_900mA:
- *val = 900000;
- break;
- case AXP20X_VBUS_CLIMIT_NONE:
- *val = -1;
- break;
- }
-
- return 0;
-}
-
-static int axp813_get_current_max(struct axp20x_usb_power *power, int *val)
-{
- unsigned int v;
- int ret = regmap_read(power->regmap, AXP20X_VBUS_IPSOUT_MGMT, &v);
-
- if (ret)
- return ret;
-
- switch (v & AXP20X_VBUS_CLIMIT_MASK) {
- case AXP813_VBUS_CLIMIT_900mA:
- *val = 900000;
- break;
- case AXP813_VBUS_CLIMIT_1500mA:
- *val = 1500000;
- break;
- case AXP813_VBUS_CLIMIT_2000mA:
- *val = 2000000;
- break;
- case AXP813_VBUS_CLIMIT_2500mA:
- *val = 2500000;
- break;
- }
- return 0;
-}
-
static int axp20x_usb_power_get_property(struct power_supply *psy,
enum power_supply_property psp, union power_supply_propval *val)
{
@@ -213,9 +160,12 @@ static int axp20x_usb_power_get_property(struct power_supply *psy,
val->intval = ret * 1700; /* 1 step = 1.7 mV */
return 0;
case POWER_SUPPLY_PROP_CURRENT_MAX:
- if (power->axp20x_id == AXP813_ID)
- return axp813_get_current_max(power, &val->intval);
- return axp20x_get_current_max(power, &val->intval);
+ ret = regmap_field_read(power->curr_lim_fld, &v);
+ if (ret)
+ return ret;
+
+ val->intval = power->axp_data->curr_lim_table[v];
+ return 0;
case POWER_SUPPLY_PROP_CURRENT_NOW:
if (IS_ENABLED(CONFIG_AXP20X_ADC)) {
ret = iio_read_channel_processed(power->vbus_i,
@@ -316,50 +266,17 @@ static int axp20x_usb_power_set_voltage_min(struct axp20x_usb_power *power,
return -EINVAL;
}

-static int axp813_usb_power_set_current_max(struct axp20x_usb_power *power,
- int intval)
+static int axp20x_usb_power_set_current_max(struct axp20x_usb_power *power, int intval)
{
- int val;
+ const unsigned int max = GENMASK(power->axp_data->curr_lim_fld.msb,
+ power->axp_data->curr_lim_fld.lsb);

- switch (intval) {
- case 900000:
- return regmap_update_bits(power->regmap,
- AXP20X_VBUS_IPSOUT_MGMT,
- AXP20X_VBUS_CLIMIT_MASK,
- AXP813_VBUS_CLIMIT_900mA);
- case 1500000:
- case 2000000:
- case 2500000:
- val = (intval - 1000000) / 500000;
- return regmap_update_bits(power->regmap,
- AXP20X_VBUS_IPSOUT_MGMT,
- AXP20X_VBUS_CLIMIT_MASK, val);
- default:
+ if (intval == -1)
return -EINVAL;
- }

- return -EINVAL;
-}
-
-static int axp20x_usb_power_set_current_max(struct axp20x_usb_power *power,
- int intval)
-{
- int val;
-
- switch (intval) {
- case 100000:
- if (power->axp20x_id == AXP221_ID)
- return -EINVAL;
- fallthrough;
- case 500000:
- case 900000:
- val = (900000 - intval) / 400000;
- return regmap_update_bits(power->regmap,
- AXP20X_VBUS_IPSOUT_MGMT,
- AXP20X_VBUS_CLIMIT_MASK, val);
- default:
- return -EINVAL;
- }
+ for (unsigned int i = 0; i <= max; ++i)
+ if (power->axp_data->curr_lim_table[i] == intval)
+ return regmap_field_write(power->curr_lim_fld, i);

return -EINVAL;
}
@@ -380,9 +297,6 @@ static int axp20x_usb_power_set_property(struct power_supply *psy,
return axp20x_usb_power_set_voltage_min(power, val->intval);

case POWER_SUPPLY_PROP_CURRENT_MAX:
- if (power->axp20x_id == AXP813_ID)
- return axp813_usb_power_set_current_max(power,
- val->intval);
return axp20x_usb_power_set_current_max(power, val->intval);

default:
@@ -461,11 +375,25 @@ static const char * const axp22x_irq_names[] = {
"VBUS_REMOVAL",
};

-struct axp_data {
- const struct power_supply_desc *power_desc;
- const char * const *irq_names;
- unsigned int num_irq_names;
- enum axp20x_variants axp20x_id;
+static int axp20x_usb_curr_lim_table[] = {
+ 900000,
+ 500000,
+ 100000,
+ -1,
+};
+
+static int axp221_usb_curr_lim_table[] = {
+ 900000,
+ 500000,
+ -1,
+ -1,
+};
+
+static int axp813_usb_curr_lim_table[] = {
+ 900000,
+ 1500000,
+ 2000000,
+ 2500000,
};

static const struct axp_data axp202_data = {
@@ -473,6 +401,8 @@ static const struct axp_data axp202_data = {
.irq_names = axp20x_irq_names,
.num_irq_names = ARRAY_SIZE(axp20x_irq_names),
.axp20x_id = AXP202_ID,
+ .curr_lim_table = axp20x_usb_curr_lim_table,
+ .curr_lim_fld = REG_FIELD(AXP20X_VBUS_IPSOUT_MGMT, 0, 1),
};

static const struct axp_data axp221_data = {
@@ -480,6 +410,8 @@ static const struct axp_data axp221_data = {
.irq_names = axp22x_irq_names,
.num_irq_names = ARRAY_SIZE(axp22x_irq_names),
.axp20x_id = AXP221_ID,
+ .curr_lim_table = axp221_usb_curr_lim_table,
+ .curr_lim_fld = REG_FIELD(AXP20X_VBUS_IPSOUT_MGMT, 0, 1),
};

static const struct axp_data axp223_data = {
@@ -487,6 +419,8 @@ static const struct axp_data axp223_data = {
.irq_names = axp22x_irq_names,
.num_irq_names = ARRAY_SIZE(axp22x_irq_names),
.axp20x_id = AXP223_ID,
+ .curr_lim_table = axp20x_usb_curr_lim_table,
+ .curr_lim_fld = REG_FIELD(AXP20X_VBUS_IPSOUT_MGMT, 0, 1),
};

static const struct axp_data axp813_data = {
@@ -494,6 +428,8 @@ static const struct axp_data axp813_data = {
.irq_names = axp22x_irq_names,
.num_irq_names = ARRAY_SIZE(axp22x_irq_names),
.axp20x_id = AXP813_ID,
+ .curr_lim_table = axp813_usb_curr_lim_table,
+ .curr_lim_fld = REG_FIELD(AXP20X_VBUS_IPSOUT_MGMT, 0, 1),
};

#ifdef CONFIG_PM_SLEEP
@@ -592,9 +528,15 @@ static int axp20x_usb_power_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, power);

power->axp20x_id = axp_data->axp20x_id;
+ power->axp_data = axp_data;
power->regmap = axp20x->regmap;
power->num_irqs = axp_data->num_irq_names;

+ power->curr_lim_fld = devm_regmap_field_alloc(&pdev->dev, power->regmap,
+ axp_data->curr_lim_fld);
+ if (IS_ERR(power->curr_lim_fld))
+ return PTR_ERR(power->curr_lim_fld);
+
ret = devm_delayed_work_autocancel(&pdev->dev, &power->vbus_detect,
axp20x_usb_power_poll_vbus);
if (ret)
--
2.39.2