thinkpad_acpi: Add support for battery thresholds
authorOgnjen Galic <smclt30p@gmail.com>
Wed, 7 Feb 2018 14:58:44 +0000 (15:58 +0100)
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>
Wed, 21 Feb 2018 22:27:13 +0000 (23:27 +0100)
1) Charge start threshold
/sys/class/power_supply/BATN/charge_start_threshold

Valid values are [0, 99]. A value of 0 turns off the
start threshold wear control.

2) Charge stop threshold
/sys/class/power_supply/BATN/charge_stop_threshold

Valid values are [1, 100]. A value of 100 turns off
the stop threshold wear control. This must be
configured first.

Signed-off-by: Ognjen Galic <smclt30p@gmail.com>
Acked-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
drivers/platform/x86/Kconfig
drivers/platform/x86/thinkpad_acpi.c

index 9a8f96465cdc3c04783f6296dcc778128c231df5..0d13d30c15cdaa8bb9640168896eaf9a1f32f7dc 100644 (file)
@@ -425,6 +425,7 @@ config SURFACE3_WMI
 config THINKPAD_ACPI
        tristate "ThinkPad ACPI Laptop Extras"
        depends on ACPI
+       depends on ACPI_BATTERY
        depends on INPUT
        depends on RFKILL || RFKILL = n
        depends on ACPI_VIDEO || ACPI_VIDEO = n
index d5eaf3b1edba91d53723fddd0c2b49125fd64b9d..1c57ee2b6d190501dd3dffe47e82fd1cf628fc4c 100644 (file)
@@ -23,7 +23,7 @@
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
-#define TPACPI_VERSION "0.25"
+#define TPACPI_VERSION "0.26"
 #define TPACPI_SYSFS_VERSION 0x030000
 
 /*
@@ -66,6 +66,7 @@
 #include <linux/seq_file.h>
 #include <linux/sysfs.h>
 #include <linux/backlight.h>
+#include <linux/bitops.h>
 #include <linux/fb.h>
 #include <linux/platform_device.h>
 #include <linux/hwmon.h>
 #include <linux/workqueue.h>
 #include <linux/acpi.h>
 #include <linux/pci_ids.h>
+#include <linux/power_supply.h>
 #include <linux/thinkpad_acpi.h>
 #include <sound/core.h>
 #include <sound/control.h>
 #include <sound/initval.h>
 #include <linux/uaccess.h>
+#include <acpi/battery.h>
 #include <acpi/video.h>
 
 /* ThinkPad CMOS commands */
@@ -335,6 +338,7 @@ static struct {
        u32 sensors_pdev_attrs_registered:1;
        u32 hotkey_poll_active:1;
        u32 has_adaptive_kbd:1;
+       u32 battery:1;
 } tp_features;
 
 static struct {
@@ -9209,6 +9213,385 @@ static struct ibm_struct mute_led_driver_data = {
        .resume = mute_led_resume,
 };
 
+/*
+ * Battery Wear Control Driver
+ * Contact: Ognjen Galic <smclt30p@gmail.com>
+ */
+
+/* Metadata */
+
+#define GET_START      "BCTG"
+#define SET_START      "BCCS"
+#define GET_STOP       "BCSG"
+#define SET_STOP       "BCSS"
+
+#define START_ATTR "charge_start_threshold"
+#define STOP_ATTR  "charge_stop_threshold"
+
+enum {
+       BAT_ANY = 0,
+       BAT_PRIMARY = 1,
+       BAT_SECONDARY = 2
+};
+
+enum {
+       /* Error condition bit */
+       METHOD_ERR = BIT(31),
+};
+
+enum {
+       /* This is used in the get/set helpers */
+       THRESHOLD_START,
+       THRESHOLD_STOP,
+};
+
+struct tpacpi_battery_data {
+       int charge_start;
+       int start_support;
+       int charge_stop;
+       int stop_support;
+};
+
+struct tpacpi_battery_driver_data {
+       struct tpacpi_battery_data batteries[3];
+       int individual_addressing;
+};
+
+static struct tpacpi_battery_driver_data battery_info;
+
+/* ACPI helpers/functions/probes */
+
+/**
+ * This evaluates a ACPI method call specific to the battery
+ * ACPI extension. The specifics are that an error is marked
+ * in the 32rd bit of the response, so we just check that here.
+ */
+static acpi_status tpacpi_battery_acpi_eval(char *method, int *ret, int param)
+{
+       int response;
+
+       if (!acpi_evalf(hkey_handle, &response, method, "dd", param)) {
+               acpi_handle_err(hkey_handle, "%s: evaluate failed", method);
+               return AE_ERROR;
+       }
+       if (response & METHOD_ERR) {
+               acpi_handle_err(hkey_handle,
+                               "%s evaluated but flagged as error", method);
+               return AE_ERROR;
+       }
+       *ret = response;
+       return AE_OK;
+}
+
+static int tpacpi_battery_get(int what, int battery, int *ret)
+{
+       switch (what) {
+       case THRESHOLD_START:
+               if ACPI_FAILURE(tpacpi_battery_acpi_eval(GET_START, ret, battery))
+                       return -ENODEV;
+
+               /* The value is in the low 8 bits of the response */
+               *ret = *ret & 0xFF;
+               return 0;
+       case THRESHOLD_STOP:
+               if ACPI_FAILURE(tpacpi_battery_acpi_eval(GET_STOP, ret, battery))
+                       return -ENODEV;
+               /* Value is in lower 8 bits */
+               *ret = *ret & 0xFF;
+               /*
+                * On the stop value, if we return 0 that
+                * does not make any sense. 0 means Default, which
+                * means that charging stops at 100%, so we return
+                * that.
+                */
+               if (*ret == 0)
+                       *ret = 100;
+               return 0;
+       default:
+               pr_crit("wrong parameter: %d", what);
+               return -EINVAL;
+       }
+}
+
+static int tpacpi_battery_set(int what, int battery, int value)
+{
+       int param, ret;
+       /* The first 8 bits are the value of the threshold */
+       param = value;
+       /* The battery ID is in bits 8-9, 2 bits */
+       param |= battery << 8;
+
+       switch (what) {
+       case THRESHOLD_START:
+               if ACPI_FAILURE(tpacpi_battery_acpi_eval(SET_START, &ret, param)) {
+                       pr_err("failed to set charge threshold on battery %d",
+                                       battery);
+                       return -ENODEV;
+               }
+               return 0;
+       case THRESHOLD_STOP:
+               if ACPI_FAILURE(tpacpi_battery_acpi_eval(SET_STOP, &ret, param)) {
+                       pr_err("failed to set stop threshold: %d", battery);
+                       return -ENODEV;
+               }
+               return 0;
+       default:
+               pr_crit("wrong parameter: %d", what);
+               return -EINVAL;
+       }
+}
+
+static int tpacpi_battery_probe(int battery)
+{
+       int ret = 0;
+
+       memset(&battery_info, 0, sizeof(struct tpacpi_battery_driver_data));
+       /*
+        * 1) Get the current start threshold
+        * 2) Check for support
+        * 3) Get the current stop threshold
+        * 4) Check for support
+        */
+       if (acpi_has_method(hkey_handle, GET_START)) {
+               if ACPI_FAILURE(tpacpi_battery_acpi_eval(GET_START, &ret, battery)) {
+                       pr_err("Error probing battery %d\n", battery);
+                       return -ENODEV;
+               }
+               /* Individual addressing is in bit 9 */
+               if (ret & BIT(9))
+                       battery_info.individual_addressing = true;
+               /* Support is marked in bit 8 */
+               if (ret & BIT(8))
+                       battery_info.batteries[battery].start_support = 1;
+               else
+                       return -ENODEV;
+               if (tpacpi_battery_get(THRESHOLD_START, battery,
+                       &battery_info.batteries[battery].charge_start)) {
+                       pr_err("Error probing battery %d\n", battery);
+                       return -ENODEV;
+               }
+       }
+       if (acpi_has_method(hkey_handle, GET_STOP)) {
+               if ACPI_FAILURE(tpacpi_battery_acpi_eval(GET_STOP, &ret, battery)) {
+                       pr_err("Error probing battery stop; %d\n", battery);
+                       return -ENODEV;
+               }
+               /* Support is marked in bit 8 */
+               if (ret & BIT(8))
+                       battery_info.batteries[battery].stop_support = 1;
+               else
+                       return -ENODEV;
+               if (tpacpi_battery_get(THRESHOLD_STOP, battery,
+                       &battery_info.batteries[battery].charge_stop)) {
+                       pr_err("Error probing battery stop: %d\n", 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);
+
+       return 0;
+}
+
+/* General helper functions */
+
+static int tpacpi_battery_get_id(const char *battery_name)
+{
+
+       if (strcmp(battery_name, "BAT0") == 0)
+               return BAT_PRIMARY;
+       if (strcmp(battery_name, "BAT1") == 0)
+               return BAT_SECONDARY;
+       /*
+        * If for some reason the battery is not BAT0 nor is it
+        * BAT1, we will assume it's the default, first battery,
+        * AKA primary.
+        */
+       pr_warn("unknown battery %s, assuming primary", battery_name);
+       return BAT_PRIMARY;
+}
+
+/* sysfs interface */
+
+static ssize_t tpacpi_battery_store(int what,
+                                   struct device *dev,
+                                   const char *buf, size_t count)
+{
+       struct power_supply *supply = to_power_supply(dev);
+       unsigned long value;
+       int battery, rval;
+       /*
+        * Some systems have support for more than
+        * one battery. If that is the case,
+        * tpacpi_battery_probe marked that addressing
+        * them individually is supported, so we do that
+        * based on the device struct.
+        *
+        * On systems that are not supported, we assume
+        * the primary as most of the ACPI calls fail
+        * with "Any Battery" as the parameter.
+        */
+       if (battery_info.individual_addressing)
+               /* BAT_PRIMARY or BAT_SECONDARY */
+               battery = tpacpi_battery_get_id(supply->desc->name);
+       else
+               battery = BAT_PRIMARY;
+
+       rval = kstrtoul(buf, 10, &value);
+       if (rval)
+               return rval;
+
+       switch (what) {
+       case THRESHOLD_START:
+               if (!battery_info.batteries[battery].start_support)
+                       return -ENODEV;
+               /* valid values are [0, 99] */
+               if (value < 0 || value > 99)
+                       return -EINVAL;
+               if (value > battery_info.batteries[battery].charge_stop)
+                       return -EINVAL;
+               if (tpacpi_battery_set(THRESHOLD_START, battery, value))
+                       return -ENODEV;
+               battery_info.batteries[battery].charge_start = value;
+               return count;
+
+       case THRESHOLD_STOP:
+               if (!battery_info.batteries[battery].stop_support)
+                       return -ENODEV;
+               /* valid values are [1, 100] */
+               if (value < 1 || value > 100)
+                       return -EINVAL;
+               if (value < battery_info.batteries[battery].charge_start)
+                       return -EINVAL;
+               battery_info.batteries[battery].charge_stop = value;
+               /*
+                * When 100 is passed to stop, we need to flip
+                * it to 0 as that the EC understands that as
+                * "Default", which will charge to 100%
+                */
+               if (value == 100)
+                       value = 0;
+               if (tpacpi_battery_set(THRESHOLD_STOP, battery, value))
+                       return -EINVAL;
+               return count;
+       default:
+               pr_crit("Wrong parameter: %d", what);
+               return -EINVAL;
+       }
+       return count;
+}
+
+static ssize_t tpacpi_battery_show(int what,
+                                  struct device *dev,
+                                  char *buf)
+{
+       struct power_supply *supply = to_power_supply(dev);
+       int ret, battery;
+       /*
+        * Some systems have support for more than
+        * one battery. If that is the case,
+        * tpacpi_battery_probe marked that addressing
+        * them individually is supported, so we;
+        * based on the device struct.
+        *
+        * On systems that are not supported, we assume
+        * the primary as most of the ACPI calls fail
+        * with "Any Battery" as the parameter.
+        */
+       if (battery_info.individual_addressing)
+               /* BAT_PRIMARY or BAT_SECONDARY */
+               battery = tpacpi_battery_get_id(supply->desc->name);
+       else
+               battery = BAT_PRIMARY;
+       if (tpacpi_battery_get(what, battery, &ret))
+               return -ENODEV;
+       return sprintf(buf, "%d\n", ret);
+}
+
+static ssize_t charge_start_threshold_show(struct device *device,
+                               struct device_attribute *attr,
+                               char *buf)
+{
+       return tpacpi_battery_show(THRESHOLD_START, device, buf);
+}
+
+static ssize_t charge_stop_threshold_show(struct device *device,
+                               struct device_attribute *attr,
+                               char *buf)
+{
+       return tpacpi_battery_show(THRESHOLD_STOP, device, buf);
+}
+
+static ssize_t charge_start_threshold_store(struct device *dev,
+                               struct device_attribute *attr,
+                               const char *buf, size_t count)
+{
+       return tpacpi_battery_store(THRESHOLD_START, dev, buf, count);
+}
+
+static ssize_t charge_stop_threshold_store(struct device *dev,
+                               struct device_attribute *attr,
+                               const char *buf, size_t count)
+{
+       return tpacpi_battery_store(THRESHOLD_STOP, dev, buf, count);
+}
+
+static DEVICE_ATTR_RW(charge_start_threshold);
+static DEVICE_ATTR_RW(charge_stop_threshold);
+
+static struct attribute *tpacpi_battery_attrs[] = {
+       &dev_attr_charge_start_threshold.attr,
+       &dev_attr_charge_stop_threshold.attr,
+       NULL,
+};
+
+ATTRIBUTE_GROUPS(tpacpi_battery);
+
+/* ACPI battery hooking */
+
+static int tpacpi_battery_add(struct power_supply *battery)
+{
+       int batteryid = tpacpi_battery_get_id(battery->desc->name);
+
+       if (tpacpi_battery_probe(batteryid))
+               return -ENODEV;
+       if (device_add_groups(&battery->dev, tpacpi_battery_groups))
+               return -ENODEV;
+       return 0;
+}
+
+static int tpacpi_battery_remove(struct power_supply *battery)
+{
+       device_remove_groups(&battery->dev, tpacpi_battery_groups);
+       return 0;
+}
+
+static struct acpi_battery_hook battery_hook = {
+       .add_battery = tpacpi_battery_add,
+       .remove_battery = tpacpi_battery_remove,
+       .name = "ThinkPad Battery Extension",
+};
+
+/* Subdriver init/exit */
+
+static int __init tpacpi_battery_init(struct ibm_init_struct *ibm)
+{
+       battery_hook_register(&battery_hook);
+       return 0;
+}
+
+static void tpacpi_battery_exit(void)
+{
+       battery_hook_unregister(&battery_hook);
+}
+
+static struct ibm_struct battery_driver_data = {
+       .name = "battery",
+       .exit = tpacpi_battery_exit,
+};
+
 /****************************************************************************
  ****************************************************************************
  *
@@ -9655,6 +10038,10 @@ static struct ibm_init_struct ibms_init[] __initdata = {
                .init = mute_led_init,
                .data = &mute_led_driver_data,
        },
+       {
+               .init = tpacpi_battery_init,
+               .data = &battery_driver_data,
+       },
 };
 
 static int __init set_ibm_param(const char *val, const struct kernel_param *kp)