* [PATCH 2/2] power: supply: qcom_battmgr: expose the charge current limit
2026-10-16 12:48 [PATCH 1/2] power: supply: qcom_battmgr: fix the battery current sign on Kaanapali Joonhoe Kim
@ 2026-10-16 12:48 ` Joonhoe Kim
2026-10-16 13:34 ` [PATCH 1/2] power: supply: qcom_battmgr: fix the battery current sign on Kaanapali Konrad Dybcio
1 sibling, 0 replies; 3+ messages in thread
From: Joonhoe Kim @ 2026-10-16 12:48 UTC (permalink / raw)
To: sre
Cc: konrad.dybcio, kamal.wadhwa, anjelique.melendez, dhruvin.rajpura,
andersson, dmitry.baryshkov, linux-arm-msm, linux-pm,
linux-kernel
The battery manager firmware takes a charge current limit in uA
(BATT_CHG_CTRL_LIM) and reports the highest value it accepts
(BATT_CHG_CTRL_LIM_MAX). Expose them on SM8550 class batteries as
charge_control_limit and charge_control_limit_max, clamping writes to
the maximum.
Also handle the BATTMGR_BAT_PROPERTY_SET response, which was logged as
an unknown message, and return its result.
On a Lenovo Legion Tab Y700 Gen 5 with a 45 W PD charger, limits of
500 mA and 100 mA give about 480 mA and 90 mA of charge current while
the PD contract stays at 9 V. A limit of 0 stops charging, and this
firmware does not resume when the limit is raised again until the end
threshold is moved below the capacity and back.
Signed-off-by: Joonhoe Kim <26rote@gmail.com>
---
The downstream qti_battery_charger driver also writes this property in
uA. The thermal mitigation series [1] used it as a level index, and
Konrad noted that the ABI defines charge_control_limit in uA; this
follows the ABI. Only tested on Kaanapali.
[1] https://lore.kernel.org/all/20260609-cooling_device_reg-v1-2-e15bddcb0086@qti.qualcomm.com/
drivers/power/supply/qcom_battmgr.c | 52 +++++++++++++++++++++++++++++
1 file changed, 52 insertions(+)
diff --git a/drivers/power/supply/qcom_battmgr.c b/drivers/power/supply/qcom_battmgr.c
index 0d55458b2881..69931827bc08 100644
--- a/drivers/power/supply/qcom_battmgr.c
+++ b/drivers/power/supply/qcom_battmgr.c
@@ -260,6 +260,8 @@ struct qcom_battmgr_info {
unsigned int charge_count;
unsigned int charge_ctrl_start;
unsigned int charge_ctrl_end;
+ unsigned int charge_ctrl_limit;
+ unsigned int charge_ctrl_limit_max;
char model_number[BATTMGR_STRING_LEN];
char serial_number[BATTMGR_STRING_LEN];
char oem_info[BATTMGR_STRING_LEN];
@@ -451,6 +453,8 @@ static const u8 sm8350_bat_prop_map[] = {
[POWER_SUPPLY_PROP_POWER_NOW] = BATT_POWER_NOW,
[POWER_SUPPLY_PROP_CHARGE_CONTROL_START_THRESHOLD] = BATT_CHG_CTRL_START_THR,
[POWER_SUPPLY_PROP_CHARGE_CONTROL_END_THRESHOLD] = BATT_CHG_CTRL_END_THR,
+ [POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT] = BATT_CHG_CTRL_LIM,
+ [POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX] = BATT_CHG_CTRL_LIM_MAX,
};
static int qcom_battmgr_bat_sm8350_update(struct qcom_battmgr *battmgr,
@@ -635,6 +639,12 @@ static int qcom_battmgr_bat_get_property(struct power_supply *psy,
case POWER_SUPPLY_PROP_CHARGE_CONTROL_END_THRESHOLD:
val->intval = battmgr->info.charge_ctrl_end;
break;
+ case POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT:
+ val->intval = battmgr->info.charge_ctrl_limit;
+ break;
+ case POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX:
+ val->intval = battmgr->info.charge_ctrl_limit_max;
+ break;
case POWER_SUPPLY_PROP_MANUFACTURE_YEAR:
val->intval = battmgr->info.year;
break;
@@ -729,6 +739,26 @@ static int qcom_battmgr_set_charge_end_threshold(struct qcom_battmgr *battmgr, i
return 0;
}
+static int qcom_battmgr_set_charge_control_limit(struct qcom_battmgr *battmgr, int limit)
+{
+ int ret;
+
+ if (limit < 0)
+ return -EINVAL;
+
+ mutex_lock(&battmgr->lock);
+ ret = qcom_battmgr_request_property(battmgr, BATTMGR_BAT_PROPERTY_GET,
+ BATT_CHG_CTRL_LIM_MAX, 0);
+ if (!ret) {
+ limit = min_t(u32, limit, battmgr->info.charge_ctrl_limit_max);
+ ret = qcom_battmgr_request_property(battmgr, BATTMGR_BAT_PROPERTY_SET,
+ BATT_CHG_CTRL_LIM, limit);
+ }
+ mutex_unlock(&battmgr->lock);
+
+ return ret;
+}
+
static int qcom_battmgr_charge_control_thresholds_init(struct qcom_battmgr *battmgr)
{
int ret;
@@ -764,6 +794,7 @@ static int qcom_battmgr_bat_is_writeable(struct power_supply *psy,
switch (psp) {
case POWER_SUPPLY_PROP_CHARGE_CONTROL_START_THRESHOLD:
case POWER_SUPPLY_PROP_CHARGE_CONTROL_END_THRESHOLD:
+ case POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT:
return 1;
default:
return 0;
@@ -786,6 +817,8 @@ static int qcom_battmgr_bat_set_property(struct power_supply *psy,
return qcom_battmgr_set_charge_start_threshold(battmgr, pval->intval);
case POWER_SUPPLY_PROP_CHARGE_CONTROL_END_THRESHOLD:
return qcom_battmgr_set_charge_end_threshold(battmgr, pval->intval);
+ case POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT:
+ return qcom_battmgr_set_charge_control_limit(battmgr, pval->intval);
default:
return -EINVAL;
}
@@ -921,6 +954,8 @@ static const enum power_supply_property sm8550_bat_props[] = {
POWER_SUPPLY_PROP_POWER_NOW,
POWER_SUPPLY_PROP_CHARGE_CONTROL_START_THRESHOLD,
POWER_SUPPLY_PROP_CHARGE_CONTROL_END_THRESHOLD,
+ POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT,
+ POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX,
};
static const struct power_supply_desc sm8550_bat_psy_desc = {
@@ -1479,11 +1514,28 @@ static void qcom_battmgr_sm8350_callback(struct qcom_battmgr *battmgr,
case BATT_CHG_CTRL_END_THR:
battmgr->info.charge_ctrl_end = le32_to_cpu(resp->intval.value);
break;
+ case BATT_CHG_CTRL_LIM:
+ battmgr->info.charge_ctrl_limit = le32_to_cpu(resp->intval.value);
+ break;
+ case BATT_CHG_CTRL_LIM_MAX:
+ battmgr->info.charge_ctrl_limit_max = le32_to_cpu(resp->intval.value);
+ break;
default:
dev_warn(battmgr->dev, "unknown property %#x\n", property);
break;
}
break;
+ case BATTMGR_BAT_PROPERTY_SET:
+ if (payload_len != sizeof(resp->intval)) {
+ dev_warn(battmgr->dev,
+ "invalid payload length for battery property set: %zd\n",
+ payload_len);
+ battmgr->error = -ENODATA;
+ return;
+ }
+
+ battmgr->error = le32_to_cpu(resp->intval.result) ? -EIO : 0;
+ break;
case BATTMGR_USB_PROPERTY_GET:
property = le32_to_cpu(resp->intval.property);
if (payload_len != sizeof(resp->intval)) {
--
2.43.0
^ permalink raw reply related [flat|nested] 3+ messages in thread* Re: [PATCH 1/2] power: supply: qcom_battmgr: fix the battery current sign on Kaanapali
2026-10-16 12:48 [PATCH 1/2] power: supply: qcom_battmgr: fix the battery current sign on Kaanapali Joonhoe Kim
2026-10-16 12:48 ` [PATCH 2/2] power: supply: qcom_battmgr: expose the charge current limit Joonhoe Kim
@ 2026-10-16 13:34 ` Konrad Dybcio
1 sibling, 0 replies; 3+ messages in thread
From: Konrad Dybcio @ 2026-10-16 13:34 UTC (permalink / raw)
To: Joonhoe Kim, sre, Jingyi Wang
Cc: kamal.wadhwa, anjelique.melendez, dhruvin.rajpura, andersson,
dmitry.baryshkov, linux-arm-msm, linux-pm, linux-kernel
On 10/16/26 2:48 PM, Joonhoe Kim wrote:
> The Kaanapali battery firmware reports the battery current with
> discharge positive: on a Lenovo Legion Tab Y700 Gen 5 current_now reads
> -9.1 A while charging and +0.57 A on battery. The power_supply ABI has
> charging positive, and upower reports such a charging battery as
> discharging.
>
> Other firmware behind the same callback uses the ABI sign [1], so
> negate the value only for qcom,kaanapali-pmic-glink.
>
> Fixes: 16a7c32e586e ("power: supply: qcom_battmgr: Add support for Glymur and Kaanapali")
> Link: https://lore.kernel.org/all/20260829054546.86210-1-jan.brummer@tabos.org/ [1]
> Signed-off-by: Joonhoe Kim <26rote@gmail.com>
> ---
> I could only check this on one device, not on MTP or QRD firmware.
> Anjelique, could you confirm the sign there?
>
> Both patches apply before or after my two battmgr patches still under
> review (USB_ADAP_TYPE v2 and the USB input current limit).
+Jingyi could you please check if this applies to QRD/MTP?
Konrad
>
> drivers/power/supply/qcom_battmgr.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/drivers/power/supply/qcom_battmgr.c b/drivers/power/supply/qcom_battmgr.c
> index a7237ba09be1..0d55458b2881 100644
> --- a/drivers/power/supply/qcom_battmgr.c
> +++ b/drivers/power/supply/qcom_battmgr.c
> @@ -313,6 +313,7 @@ struct qcom_battmgr {
> struct pmic_glink_client *client;
>
> enum qcom_battmgr_variant variant;
> + bool current_inverted;
>
> struct power_supply *ac_psy;
> struct power_supply *bat_psy;
> @@ -1435,6 +1436,8 @@ static void qcom_battmgr_sm8350_callback(struct qcom_battmgr *battmgr,
> break;
> case BATT_CURR_NOW:
> battmgr->status.current_now = le32_to_cpu(resp->intval.value);
> + if (battmgr->current_inverted)
> + battmgr->status.current_now = -battmgr->status.current_now;
> break;
> case BATT_TEMP:
> val = le32_to_cpu(resp->intval.value);
> @@ -1659,6 +1662,9 @@ static int qcom_battmgr_probe(struct auxiliary_device *adev,
> else
> battmgr->variant = QCOM_BATTMGR_SM8350;
>
> + battmgr->current_inverted = device_is_compatible(dev->parent,
> + "qcom,kaanapali-pmic-glink");
> +
> ret = qcom_battmgr_charge_control_thresholds_init(battmgr);
> if (ret < 0)
> return dev_err_probe(dev, ret,
>
> base-commit: b810335a0699d1810683796b0e3ffe8827ddfe6c
^ permalink raw reply [flat|nested] 3+ messages in thread