[PATCH 3/4] platform/x86: thinkpad_acpi: support force-discharge
From: Thomas Weißschuh
Date: Sat Nov 13 2021 - 05:45:35 EST
This adds support for the force-discharge charge_behaviour through the
embedded controller of ThinkPads.
Signed-off-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
---
This patch is based on https://lore.kernel.org/platform-driver-x86/c2504700-06e9-e7d8-80f7-de90b0b6dfb5@xxxxxxxxx/
---
drivers/platform/x86/thinkpad_acpi.c | 103 +++++++++++++++++++++++++--
1 file changed, 99 insertions(+), 4 deletions(-)
diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
index 9c632df734bb..e8c98e9aff71 100644
--- a/drivers/platform/x86/thinkpad_acpi.c
+++ b/drivers/platform/x86/thinkpad_acpi.c
@@ -9319,6 +9319,8 @@ static struct ibm_struct mute_led_driver_data = {
#define SET_START "BCCS"
#define GET_STOP "BCSG"
#define SET_STOP "BCSS"
+#define GET_DISCHARGE "BDSG"
+#define SET_DISCHARGE "BDSS"
enum {
BAT_ANY = 0,
@@ -9335,6 +9337,7 @@ enum {
/* This is used in the get/set helpers */
THRESHOLD_START,
THRESHOLD_STOP,
+ FORCE_DISCHARGE,
};
struct tpacpi_battery_data {
@@ -9342,6 +9345,7 @@ struct tpacpi_battery_data {
int start_support;
int charge_stop;
int stop_support;
+ unsigned int charge_behaviours;
};
struct tpacpi_battery_driver_data {
@@ -9399,6 +9403,12 @@ static int tpacpi_battery_get(int what, int battery, int *ret)
if (*ret == 0)
*ret = 100;
return 0;
+ case FORCE_DISCHARGE:
+ if ACPI_FAILURE(tpacpi_battery_acpi_eval(GET_DISCHARGE, ret, battery))
+ return -ENODEV;
+ /* The force discharge status is in bit 0 */
+ *ret = *ret & 0x01;
+ return 0;
default:
pr_crit("wrong parameter: %d", what);
return -EINVAL;
@@ -9427,6 +9437,16 @@ static int tpacpi_battery_set(int what, int battery, int value)
return -ENODEV;
}
return 0;
+ case FORCE_DISCHARGE:
+ /* Force discharge is in bit 0,
+ * break on AC attach is in bit 1 (won't work on some ThinkPads),
+ * battery ID is in bits 8-9, 2 bits.
+ */
+ if (ACPI_FAILURE(tpacpi_battery_acpi_eval(SET_DISCHARGE, &ret, param))) {
+ pr_err("failed to set force dischrage on %d", battery);
+ return -ENODEV;
+ }
+ return 0;
default:
pr_crit("wrong parameter: %d", what);
return -EINVAL;
@@ -9445,6 +9465,8 @@ static int tpacpi_battery_probe(int battery)
* 2) Check for support
* 3) Get the current stop threshold
* 4) Check for support
+ * 5) Get the current force discharge status
+ * 6) Check for support
*/
if (acpi_has_method(hkey_handle, GET_START)) {
if ACPI_FAILURE(tpacpi_battery_acpi_eval(GET_START, &ret, battery)) {
@@ -9481,10 +9503,25 @@ static int tpacpi_battery_probe(int battery)
return -ENODEV;
}
}
- pr_info("battery %d registered (start %d, stop %d)",
- battery,
- battery_info.batteries[battery].charge_start,
- battery_info.batteries[battery].charge_stop);
+ if (acpi_has_method(hkey_handle, GET_DISCHARGE)) {
+ if (ACPI_FAILURE(tpacpi_battery_acpi_eval(GET_DISCHARGE, &ret, battery))) {
+ pr_err("Error probing battery discharge; %d\n", battery);
+ return -ENODEV;
+ }
+ /* Support is marked in bit 8 */
+ if (ret & BIT(8))
+ battery_info.batteries[battery].charge_behaviours |=
+ BIT(POWER_SUPPLY_CHARGE_BEHAVIOUR_FORCE_DISCHARGE);
+ }
+
+ battery_info.batteries[battery].charge_behaviours |=
+ BIT(POWER_SUPPLY_CHARGE_BEHAVIOUR_AUTO);
+
+ pr_info("battery %d registered (start %d, stop %d, behaviours: 0x%x)\n",
+ battery,
+ battery_info.batteries[battery].charge_start,
+ battery_info.batteries[battery].charge_stop,
+ battery_info.batteries[battery].charge_behaviours);
return 0;
}
@@ -9619,6 +9656,28 @@ static ssize_t charge_control_end_threshold_show(struct device *device,
return tpacpi_battery_show(THRESHOLD_STOP, device, buf);
}
+static ssize_t charge_behaviour_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ enum power_supply_charge_behaviour active = POWER_SUPPLY_CHARGE_BEHAVIOUR_AUTO;
+ struct power_supply *supply = to_power_supply(dev);
+ unsigned int available;
+ int ret, battery;
+
+ battery = tpacpi_battery_get_id(supply->desc->name);
+ available = battery_info.batteries[battery].charge_behaviours;
+
+ if (available & BIT(POWER_SUPPLY_CHARGE_BEHAVIOUR_FORCE_DISCHARGE)) {
+ if (tpacpi_battery_get(FORCE_DISCHARGE, battery, &ret))
+ return -ENODEV;
+ if (ret)
+ active = POWER_SUPPLY_CHARGE_BEHAVIOUR_FORCE_DISCHARGE;
+ }
+
+ return power_supply_charge_behaviour_show(dev, available, active, buf);
+}
+
static ssize_t charge_control_start_threshold_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
@@ -9633,8 +9692,43 @@ static ssize_t charge_control_end_threshold_store(struct device *dev,
return tpacpi_battery_store(THRESHOLD_STOP, dev, buf, count);
}
+static ssize_t charge_behaviour_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct power_supply *supply = to_power_supply(dev);
+ int selected, battery, ret;
+ unsigned int available;
+
+ battery = tpacpi_battery_get_id(supply->desc->name);
+ available = battery_info.batteries[battery].charge_behaviours;
+ selected = power_supply_charge_behaviour_parse(available, buf);
+
+ if (selected < 0)
+ return selected;
+
+ switch (selected) {
+ case POWER_SUPPLY_CHARGE_BEHAVIOUR_AUTO:
+ ret = tpacpi_battery_set(FORCE_DISCHARGE, battery, 0);
+ if (ret < 0)
+ return ret;
+ break;
+ case POWER_SUPPLY_CHARGE_BEHAVIOUR_FORCE_DISCHARGE:
+ ret = tpacpi_battery_set(FORCE_DISCHARGE, battery, 1);
+ if (ret < 0)
+ return ret;
+ break;
+ default:
+ dev_err(dev, "Unexpected charge behaviour: %d\n", selected);
+ return -EINVAL;
+ }
+
+ return count;
+}
+
static DEVICE_ATTR_RW(charge_control_start_threshold);
static DEVICE_ATTR_RW(charge_control_end_threshold);
+static DEVICE_ATTR_RW(charge_behaviour);
static struct device_attribute dev_attr_charge_start_threshold = __ATTR(
charge_start_threshold,
0644,
@@ -9653,6 +9747,7 @@ static struct attribute *tpacpi_battery_attrs[] = {
&dev_attr_charge_control_end_threshold.attr,
&dev_attr_charge_start_threshold.attr,
&dev_attr_charge_stop_threshold.attr,
+ &dev_attr_charge_behaviour.attr,
NULL,
};
--
2.33.1