[PATCH v3 2/4] platform/x86/uniwill: Implement USB-C power priority setting

From: Werner Sembach

Date: Fri Feb 27 2026 - 15:11:31 EST


On some devices Uniwill offers the option to set the USB-C port to
prioritise charging or performance. This patch exposes this setting to the
userspace via sysfs for all TUXEDO devices supporting it.

Signed-off-by: Werner Sembach <wse@xxxxxxxxxxxxxxxxxxx>
---
drivers/platform/x86/uniwill/uniwill-acpi.c | 147 +++++++++++++++++++-
1 file changed, 140 insertions(+), 7 deletions(-)

diff --git a/drivers/platform/x86/uniwill/uniwill-acpi.c b/drivers/platform/x86/uniwill/uniwill-acpi.c
index 048b265bff374..f92c24d64160b 100644
--- a/drivers/platform/x86/uniwill/uniwill-acpi.c
+++ b/drivers/platform/x86/uniwill/uniwill-acpi.c
@@ -266,8 +266,8 @@
#define BATTERY_CHARGE_FULL_OVER_24H BIT(3)
#define BATTERY_ERM_STATUS_REACHED BIT(4)

-#define EC_ADDR_CHARGE_PRIO 0x07CC
-#define CHARGING_PERFORMANCE BIT(7)
+#define EC_ADDR_USB_C_POWER_PRIORITY 0x07CC
+#define USB_C_POWER_PRIORITY BIT(7)

/* Same bits as EC_ADDR_LIGHTBAR_AC_CTRL except LIGHTBAR_S3_OFF */
#define EC_ADDR_LIGHTBAR_BAT_CTRL 0x07E2
@@ -324,6 +324,12 @@
#define UNIWILL_FEATURE_PRIMARY_FAN BIT(7)
#define UNIWILL_FEATURE_SECONDARY_FAN BIT(8)
#define UNIWILL_FEATURE_NVIDIA_CTGP_CONTROL BIT(9)
+#define UNIWILL_FEATURE_USB_C_POWER_PRIORITY BIT(10)
+
+enum usb_c_power_priority_options {
+ USB_C_POWER_PRIORITY_OPTIONS_CHARGING = 0,
+ USB_C_POWER_PRIORITY_OPTIONS_PERFORMANCE,
+};

struct uniwill_data {
struct device *dev;
@@ -343,6 +349,8 @@ struct uniwill_data {
struct mutex input_lock; /* Protects input sequence during notify */
struct input_dev *input_device;
struct notifier_block nb;
+ struct mutex usb_c_power_priority_lock; /* Protects dependent bit write and state safe */
+ enum usb_c_power_priority_options last_usb_c_power_priority_option;
};

struct uniwill_battery_entry {
@@ -527,6 +535,7 @@ static bool uniwill_writeable_reg(struct device *dev, unsigned int reg)
case EC_ADDR_CTGP_DB_CTGP_OFFSET:
case EC_ADDR_CTGP_DB_TPP_OFFSET:
case EC_ADDR_CTGP_DB_DB_OFFSET:
+ case EC_ADDR_USB_C_POWER_PRIORITY:
return true;
default:
return false;
@@ -565,6 +574,7 @@ static bool uniwill_readable_reg(struct device *dev, unsigned int reg)
case EC_ADDR_CTGP_DB_CTGP_OFFSET:
case EC_ADDR_CTGP_DB_TPP_OFFSET:
case EC_ADDR_CTGP_DB_DB_OFFSET:
+ case EC_ADDR_USB_C_POWER_PRIORITY:
return true;
default:
return false;
@@ -587,6 +597,7 @@ static bool uniwill_volatile_reg(struct device *dev, unsigned int reg)
case EC_ADDR_TRIGGER:
case EC_ADDR_SWITCH_STATUS:
case EC_ADDR_CHARGE_CTRL:
+ case EC_ADDR_USB_C_POWER_PRIORITY:
return true;
default:
return false;
@@ -883,6 +894,106 @@ static int uniwill_nvidia_ctgp_init(struct uniwill_data *data)
return 0;
}

+static const char * const USB_C_POWER_PRIORITY_OPTIONS_TEXT[] = {
+ [USB_C_POWER_PRIORITY_OPTIONS_CHARGING] = "charging",
+ [USB_C_POWER_PRIORITY_OPTIONS_PERFORMANCE] = "performance",
+};
+
+static const u8 USB_C_POWER_PRIORITY_OPTIONS_VALUE[] = {
+ [USB_C_POWER_PRIORITY_OPTIONS_CHARGING] = 0,
+ [USB_C_POWER_PRIORITY_OPTIONS_PERFORMANCE] = USB_C_POWER_PRIORITY,
+};
+
+static ssize_t usb_c_power_priority_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct uniwill_data *data = dev_get_drvdata(dev);
+ enum usb_c_power_priority_options option;
+ unsigned int value;
+ int ret;
+
+ option = sysfs_match_string(USB_C_POWER_PRIORITY_OPTIONS_TEXT, buf);
+ if (option < 0)
+ return option;
+
+ value = USB_C_POWER_PRIORITY_OPTIONS_VALUE[option];
+
+ guard(mutex)(&data->usb_c_power_priority_lock);
+
+ ret = regmap_update_bits(data->regmap, EC_ADDR_USB_C_POWER_PRIORITY,
+ USB_C_POWER_PRIORITY, value);
+ if (ret < 0)
+ return ret;
+
+ data->last_usb_c_power_priority_option = option;
+
+ return count;
+}
+
+static ssize_t usb_c_power_priority_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct uniwill_data *data = dev_get_drvdata(dev);
+ unsigned int value, i;
+ int ret;
+
+ ret = regmap_read(data->regmap, EC_ADDR_USB_C_POWER_PRIORITY, &value);
+ if (ret < 0)
+ return ret;
+
+ value &= USB_C_POWER_PRIORITY;
+
+ for (i = 0; i < ARRAY_SIZE(USB_C_POWER_PRIORITY_OPTIONS_VALUE); ++i)
+ if (USB_C_POWER_PRIORITY_OPTIONS_VALUE[i] == value)
+ return sysfs_emit(buf, "%s\n",
+ USB_C_POWER_PRIORITY_OPTIONS_TEXT[i]);
+
+ /* Since all possible values are valid, this should be unreachable. */
+ return -EINVAL;
+}
+
+static DEVICE_ATTR_RW(usb_c_power_priority);
+
+static int usb_c_power_priority_restore(struct uniwill_data *data)
+{
+ unsigned int value;
+
+ value = USB_C_POWER_PRIORITY_OPTIONS_VALUE[data->last_usb_c_power_priority_option];
+
+ return regmap_update_bits(data->regmap, EC_ADDR_USB_C_POWER_PRIORITY,
+ USB_C_POWER_PRIORITY, value);
+}
+
+static int usb_c_power_priority_init(struct uniwill_data *data)
+{
+ unsigned int value, i;
+ int ret;
+
+ if (!uniwill_device_supports(data, UNIWILL_FEATURE_USB_C_POWER_PRIORITY))
+ return 0;
+
+ ret = devm_mutex_init(data->dev, &data->usb_c_power_priority_lock);
+ if (ret < 0)
+ return ret;
+
+ ret = regmap_read(data->regmap, EC_ADDR_USB_C_POWER_PRIORITY, &value);
+ if (ret < 0)
+ return ret;
+
+ value &= USB_C_POWER_PRIORITY;
+
+ for (i = 0; i < ARRAY_SIZE(USB_C_POWER_PRIORITY_OPTIONS_VALUE); ++i)
+ if (USB_C_POWER_PRIORITY_OPTIONS_VALUE[i] == value) {
+ data->last_usb_c_power_priority_option = i;
+ return 0;
+ }
+
+ /* Since all possible values are valid, this should be unreachable. */
+ return -EINVAL;
+}
+
static struct attribute *uniwill_attrs[] = {
/* Keyboard-related */
&dev_attr_fn_lock.attr,
@@ -893,6 +1004,7 @@ static struct attribute *uniwill_attrs[] = {
&dev_attr_breathing_in_suspend.attr,
/* Power-management-related */
&dev_attr_ctgp_offset.attr,
+ &dev_attr_usb_c_power_priority.attr,
NULL
};

@@ -927,6 +1039,11 @@ static umode_t uniwill_attr_is_visible(struct kobject *kobj, struct attribute *a
return attr->mode;
}

+ if (attr == &dev_attr_usb_c_power_priority.attr) {
+ if (uniwill_device_supports(data, UNIWILL_FEATURE_USB_C_POWER_PRIORITY))
+ return attr->mode;
+ }
+
return 0;
}

@@ -1417,11 +1534,10 @@ static int uniwill_notifier_call(struct notifier_block *nb, unsigned long action

return NOTIFY_OK;
case UNIWILL_OSD_DC_ADAPTER_CHANGED:
- /* noop for the time being, will change once charging priority
- * gets implemented.
- */
+ if (!uniwill_device_supports(data, UNIWILL_FEATURE_USB_C_POWER_PRIORITY))
+ return NOTIFY_DONE;

- return NOTIFY_OK;
+ return notifier_from_errno(usb_c_power_priority_restore(data));
case UNIWILL_OSD_FN_LOCK:
if (!uniwill_device_supports(data, UNIWILL_FEATURE_FN_LOCK))
return NOTIFY_DONE;
@@ -1515,10 +1631,15 @@ static int uniwill_probe(struct platform_device *pdev)
return PTR_ERR(regmap);

data->regmap = regmap;
+
ret = devm_mutex_init(&pdev->dev, &data->super_key_lock);
if (ret < 0)
return ret;

+ ret = usb_c_power_priority_init(data);
+ if (ret < 0)
+ return ret;
+
ret = uniwill_ec_init(data);
if (ret < 0)
return ret;
@@ -1681,6 +1802,14 @@ static int uniwill_resume_nvidia_ctgp(struct uniwill_data *data)
CTGP_DB_DB_ENABLE | CTGP_DB_CTGP_ENABLE);
}

+static int uniwill_resume_usb_c_power_priority(struct uniwill_data *data)
+{
+ if (!uniwill_device_supports(data, UNIWILL_FEATURE_USB_C_POWER_PRIORITY))
+ return 0;
+
+ return usb_c_power_priority_restore(data);
+}
+
static int uniwill_resume(struct device *dev)
{
struct uniwill_data *data = dev_get_drvdata(dev);
@@ -1704,7 +1833,11 @@ static int uniwill_resume(struct device *dev)
if (ret < 0)
return ret;

- return uniwill_resume_nvidia_ctgp(data);
+ ret = uniwill_resume_nvidia_ctgp(data);
+ if (ret < 0)
+ return ret;
+
+ return uniwill_resume_usb_c_power_priority(data);
}

static DEFINE_SIMPLE_DEV_PM_OPS(uniwill_pm_ops, uniwill_suspend, uniwill_resume);
--
2.43.0