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[PATCH 2/3] thinkpad_acpi: add support for inhibit_charge
From ca9de2cf93e89bdfc9d9634e141739691be63fb7 Mon Sep 17 00:00:00 2001
From: Thomas Koch <linrunner@gmx.net>
Date: Fri, 26 Jun 2020 09:25:34 +0200
Subject: [PATCH 2/3] thinkpad_acpi: add support for inhibit_charge
Lenovo ThinkPad systems support to hold battery charging
via a manual override called Inhibit Charge.
This patch implements that feature and exposes it via the generic
ACPI battery driver in the generic location:
/sys/class/power_supply/BATx/inhibit_charge
Signed-off-by: Thomas Koch <linrunner@gmx.net>
---
drivers/platform/x86/thinkpad_acpi.c | 68 ++++++++++++++++++++++++++--
1 file changed, 63 insertions(+), 5 deletions(-)
diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
index 6c7dca3a10d2..a13feb1d7313 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_STOP "BCSS"
#define GET_DISCHARGE "BDSG"
#define SET_DISCHARGE "BDSS"
+#define GET_INHIBIT "PSSG"
+#define SET_INHIBIT "BICS"
enum {
BAT_ANY = 0,
@@ -9335,7 +9337,8 @@ enum {
/* This is used in the get/set helpers */
THRESHOLD_START,
THRESHOLD_STOP,
- FORCE_DISCHARGE
+ FORCE_DISCHARGE,
+ INHIBIT_CHARGE
};
struct tpacpi_battery_data {
@@ -9344,6 +9347,7 @@ struct tpacpi_battery_data {
int charge_stop;
int stop_support;
int discharge_support;
+ int inhibit_support;
};
struct tpacpi_battery_driver_data {
@@ -9407,6 +9411,13 @@ static int tpacpi_battery_get(int what, int battery, int *ret)
/* The force discharge status is in bit 0 */
*ret = *ret & 0x01;
return 0;
+ case INHIBIT_CHARGE:
+ /* This is actually reading peak shift state, like tpacpi-bat does */
+ if ACPI_FAILURE(tpacpi_battery_acpi_eval(GET_INHIBIT, ret, battery))
+ return -ENODEV;
+ /* The inhibit charge status is in bit 0 */
+ *ret = *ret & 0x01;
+ return 0;
default:
pr_crit("wrong parameter: %d", what);
return -EINVAL;
@@ -9445,6 +9456,22 @@ static int tpacpi_battery_set(int what, int battery, int value)
return -ENODEV;
}
return 0;
+ case INHIBIT_CHARGE:
+ /* When setting inhibit charge, we set a default value of
+ * always breaking on AC detach and the effective time is set to
+ * be permanent.
+ * The battery ID is in bits 4-5, 2 bits,
+ * the effective time is in bits 8-23, 2 bytes.
+ * A time of FFFF indicates forever.
+ */
+ param = value;
+ param |= battery << 4;
+ param |= 0xFFFF << 8;
+ if ACPI_FAILURE(tpacpi_battery_acpi_eval(SET_INHIBIT, &ret, param)) {
+ pr_err("failed to set inhibit charge on %d", battery);
+ return -ENODEV;
+ }
+ return 0;
default:
pr_crit("wrong parameter: %d", what);
return -EINVAL;
@@ -9465,6 +9492,8 @@ static int tpacpi_battery_probe(int battery)
* 4) Check for support
* 5) Get the current force discharge status
* 6) Check for support
+ * 7) Get the current inhibit charge status
+ * 8) Check for support
*/
if (acpi_has_method(hkey_handle, GET_START)) {
if ACPI_FAILURE(tpacpi_battery_acpi_eval(GET_START, &ret, battery)) {
@@ -9505,12 +9534,17 @@ static int tpacpi_battery_probe(int battery)
if (!ACPI_FAILURE(tpacpi_battery_acpi_eval(GET_DISCHARGE, &ret, battery)))
/* Support is marked in bit 8 */
battery_info.batteries[battery].discharge_support = ret & BIT(8);
+ if (acpi_has_method(hkey_handle, GET_INHIBIT))
+ if (!ACPI_FAILURE(tpacpi_battery_acpi_eval(GET_INHIBIT, &ret, battery)))
+ /* Support is marked in bit 5 */
+ battery_info.batteries[battery].inhibit_support = ret & BIT(5);
- pr_info("battery %d registered (start %d, stop %d, force: %d)",
+ pr_info("battery %d registered (start %d, stop %d, force: %d, inhibit: %d)",
battery,
battery_info.batteries[battery].charge_start,
battery_info.batteries[battery].charge_stop,
- battery_info.batteries[battery].discharge_support);
+ battery_info.batteries[battery].discharge_support,
+ battery_info.batteries[battery].inhibit_support);
return 0;
}
@@ -9576,7 +9610,6 @@ static ssize_t tpacpi_battery_store(int what,
return -ENODEV;
battery_info.batteries[battery].charge_start = value;
return count;
-
case THRESHOLD_STOP:
if (!battery_info.batteries[battery].stop_support)
return -ENODEV;
@@ -9605,6 +9638,15 @@ static ssize_t tpacpi_battery_store(int what,
if (tpacpi_battery_set(FORCE_DISCHARGE, battery, value))
return -ENODEV;
return count;
+ case INHIBIT_CHARGE:
+ if (!battery_info.batteries[battery].inhibit_support)
+ return -ENODEV;
+ /* The only valid values are 1 and 0 */
+ if (value != 0 && value != 1)
+ return -EINVAL;
+ if (tpacpi_battery_set(INHIBIT_CHARGE, battery, value))
+ return -ENODEV;
+ return count;
default:
pr_crit("Wrong parameter: %d", what);
return -EINVAL;
@@ -9660,6 +9702,13 @@ static ssize_t force_discharge_show(struct device *device,
return tpacpi_battery_show(FORCE_DISCHARGE, device, buf);
}
+static ssize_t inhibit_charge_show(struct device *device,
+ struct device_attribute *attr,
+ char *buf)
+{
+ return tpacpi_battery_show(INHIBIT_CHARGE, device, buf);
+}
+
static ssize_t charge_control_start_threshold_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
@@ -9681,9 +9730,17 @@ static ssize_t force_discharge_store(struct device *dev,
return tpacpi_battery_store(FORCE_DISCHARGE, dev, buf, count);
}
+static ssize_t inhibit_charge_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ return tpacpi_battery_store(INHIBIT_CHARGE, dev, buf, count);
+}
+
static DEVICE_ATTR_RW(charge_control_start_threshold);
static DEVICE_ATTR_RW(charge_control_end_threshold);
static DEVICE_ATTR_RW(force_discharge);
+static DEVICE_ATTR_RW(inhibit_charge);
static struct device_attribute dev_attr_charge_start_threshold = __ATTR(
charge_start_threshold,
0644,
@@ -9702,7 +9759,8 @@ static struct attribute *tpacpi_battery_attrs[] = {
&dev_attr_charge_start_threshold.attr,
&dev_attr_charge_stop_threshold.attr,
&dev_attr_force_discharge.attr,
- NULL,
+ &dev_attr_inhibit_charge.attr,
+ NULL
};
ATTRIBUTE_GROUPS(tpacpi_battery);
--
2.25.1
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