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Diffstat (limited to 'drivers/power/olpc_battery.c')
-rw-r--r--drivers/power/olpc_battery.c352
1 files changed, 352 insertions, 0 deletions
diff --git a/drivers/power/olpc_battery.c b/drivers/power/olpc_battery.c
new file mode 100644
index 0000000..878684d
--- /dev/null
+++ b/drivers/power/olpc_battery.c
@@ -0,0 +1,352 @@
+/*
+ * Battery driver for One Laptop Per Child board.
+ *
+ * Copyright © 2006 David Woodhouse <dwmw2@infradead.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/power_supply.h>
+#include <linux/jiffies.h>
+#include <linux/sched.h>
+#include <asm/olpc.h>
+
+
+#define EC_BAT_VOLTAGE 0x10 /* uint16_t, *9.76/32, mV */
+#define EC_BAT_CURRENT 0x11 /* int16_t, *15.625/120, mA */
+#define EC_BAT_ACR 0x12
+#define EC_BAT_TEMP 0x13 /* uint16_t, *100/256, °C */
+#define EC_AMB_TEMP 0x14 /* uint16_t, *100/256, °C */
+#define EC_BAT_STATUS 0x15 /* uint8_t, bitmask */
+#define EC_BAT_SOC 0x16 /* uint8_t, percentage */
+#define EC_BAT_SERIAL 0x17 /* uint8_t[6] */
+#define EC_BAT_EEPROM 0x18 /* uint8_t adr as input, uint8_t output */
+#define EC_BAT_ERRCODE 0x1f /* uint8_t, bitmask */
+
+#define BAT_STAT_PRESENT 0x01
+#define BAT_STAT_FULL 0x02
+#define BAT_STAT_LOW 0x04
+#define BAT_STAT_DESTROY 0x08
+#define BAT_STAT_AC 0x10
+#define BAT_STAT_CHARGING 0x20
+#define BAT_STAT_DISCHARGING 0x40
+
+#define BAT_ERR_INFOFAIL 0x02
+#define BAT_ERR_OVERVOLTAGE 0x04
+#define BAT_ERR_OVERTEMP 0x05
+#define BAT_ERR_GAUGESTOP 0x06
+#define BAT_ERR_OUT_OF_CONTROL 0x07
+#define BAT_ERR_ID_FAIL 0x09
+#define BAT_ERR_ACR_FAIL 0x10
+
+#define BAT_ADDR_MFR_TYPE 0x5F
+
+/*********************************************************************
+ * Power
+ *********************************************************************/
+
+static int olpc_ac_get_prop(struct power_supply *psy,
+ enum power_supply_property psp,
+ union power_supply_propval *val)
+{
+ int ret = 0;
+ uint8_t status;
+
+ switch (psp) {
+ case POWER_SUPPLY_PROP_ONLINE:
+ ret = olpc_ec_cmd(EC_BAT_STATUS, NULL, 0, &status, 1);
+ if (ret)
+ return ret;
+
+ val->intval = !!(status & BAT_STAT_AC);
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+ return ret;
+}
+
+static enum power_supply_property olpc_ac_props[] = {
+ POWER_SUPPLY_PROP_ONLINE,
+};
+
+static struct power_supply olpc_ac = {
+ .name = "olpc-ac",
+ .type = POWER_SUPPLY_TYPE_MAINS,
+ .properties = olpc_ac_props,
+ .num_properties = ARRAY_SIZE(olpc_ac_props),
+ .get_property = olpc_ac_get_prop,
+};
+
+/*********************************************************************
+ * Battery properties
+ *********************************************************************/
+static int olpc_bat_get_property(struct power_supply *psy,
+ enum power_supply_property psp,
+ union power_supply_propval *val)
+{
+ int ret = 0;
+ int16_t ec_word;
+ uint8_t ec_byte;
+
+ ret = olpc_ec_cmd(EC_BAT_STATUS, NULL, 0, &ec_byte, 1);
+ if (ret)
+ return ret;
+
+ /* Theoretically there's a race here -- the battery could be
+ removed immediately after we check whether it's present, and
+ then we query for some other property of the now-absent battery.
+ It doesn't matter though -- the EC will return the last-known
+ information, and it's as if we just ran that _little_ bit faster
+ and managed to read it out before the battery went away. */
+ if (!(ec_byte & BAT_STAT_PRESENT) && psp != POWER_SUPPLY_PROP_PRESENT)
+ return -ENODEV;
+
+ switch (psp) {
+ case POWER_SUPPLY_PROP_STATUS:
+ if (olpc_platform_info.ecver > 0x44) {
+ if (ec_byte & BAT_STAT_CHARGING)
+ val->intval = POWER_SUPPLY_STATUS_CHARGING;
+ else if (ec_byte & BAT_STAT_DISCHARGING)
+ val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
+ else if (ec_byte & BAT_STAT_FULL)
+ val->intval = POWER_SUPPLY_STATUS_FULL;
+ else /* er,... */
+ val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
+ } else {
+ /* Older EC didn't report charge/discharge bits */
+ if (!(ec_byte & BAT_STAT_AC)) /* No AC means discharging */
+ val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
+ else if (ec_byte & BAT_STAT_FULL)
+ val->intval = POWER_SUPPLY_STATUS_FULL;
+ else /* Not _necessarily_ true but EC doesn't tell all yet */
+ val->intval = POWER_SUPPLY_STATUS_CHARGING;
+ break;
+ }
+ case POWER_SUPPLY_PROP_PRESENT:
+ val->intval = !!(ec_byte & BAT_STAT_PRESENT);
+ break;
+
+ case POWER_SUPPLY_PROP_HEALTH:
+ if (ec_byte & BAT_STAT_DESTROY)
+ val->intval = POWER_SUPPLY_HEALTH_DEAD;
+ else {
+ ret = olpc_ec_cmd(EC_BAT_ERRCODE, NULL, 0, &ec_byte, 1);
+ if (ret)
+ return ret;
+
+ switch (ec_byte) {
+ case 0:
+ val->intval = POWER_SUPPLY_HEALTH_GOOD;
+ break;
+
+ case BAT_ERR_OVERTEMP:
+ val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;
+ break;
+
+ case BAT_ERR_OVERVOLTAGE:
+ val->intval = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
+ break;
+
+ case BAT_ERR_INFOFAIL:
+ case BAT_ERR_OUT_OF_CONTROL:
+ case BAT_ERR_ID_FAIL:
+ case BAT_ERR_ACR_FAIL:
+ val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
+ break;
+
+ default:
+ /* Eep. We don't know this failure code */
+ return -EIO;
+ }
+ }
+ break;
+
+ case POWER_SUPPLY_PROP_MANUFACTURER:
+ ec_byte = BAT_ADDR_MFR_TYPE;
+ ret = olpc_ec_cmd(EC_BAT_EEPROM, &ec_byte, 1, &ec_byte, 1);
+ if (ret)
+ return ret;
+
+ switch (ec_byte >> 4) {
+ case 1:
+ val->strval = "Gold Peak";
+ break;
+ case 2:
+ val->strval = "BYD";
+ break;
+ default:
+ val->strval = "Unknown";
+ break;
+ }
+ break;
+ case POWER_SUPPLY_PROP_TECHNOLOGY:
+ ec_byte = BAT_ADDR_MFR_TYPE;
+ ret = olpc_ec_cmd(EC_BAT_EEPROM, &ec_byte, 1, &ec_byte, 1);
+ if (ret)
+ return ret;
+
+ switch (ec_byte & 0xf) {
+ case 1:
+ val->intval = POWER_SUPPLY_TECHNOLOGY_NiMH;
+ break;
+ case 2:
+ val->intval = POWER_SUPPLY_TECHNOLOGY_LiFe;
+ break;
+ default:
+ val->intval = POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
+ break;
+ }
+ break;
+ case POWER_SUPPLY_PROP_VOLTAGE_AVG:
+ ret = olpc_ec_cmd(EC_BAT_VOLTAGE, NULL, 0, (void *)&ec_word, 2);
+ if (ret)
+ return ret;
+
+ ec_word = be16_to_cpu(ec_word);
+ val->intval = ec_word * 9760L / 32;
+ break;
+ case POWER_SUPPLY_PROP_CURRENT_AVG:
+ ret = olpc_ec_cmd(EC_BAT_CURRENT, NULL, 0, (void *)&ec_word, 2);
+ if (ret)
+ return ret;
+
+ ec_word = be16_to_cpu(ec_word);
+ val->intval = ec_word * 15625L / 120;
+ break;
+ case POWER_SUPPLY_PROP_CAPACITY:
+ ret = olpc_ec_cmd(EC_BAT_SOC, NULL, 0, &ec_byte, 1);
+ if (ret)
+ return ret;
+ val->intval = ec_byte;
+ break;
+ case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
+ if (ec_byte & BAT_STAT_FULL)
+ val->intval = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
+ else if (ec_byte & BAT_STAT_LOW)
+ val->intval = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
+ else
+ val->intval = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
+ break;
+ case POWER_SUPPLY_PROP_TEMP:
+ ret = olpc_ec_cmd(EC_BAT_TEMP, NULL, 0, (void *)&ec_word, 2);
+ if (ret)
+ return ret;
+ ec_word = be16_to_cpu(ec_word);
+ val->intval = ec_word * 100 / 256;
+ break;
+ case POWER_SUPPLY_PROP_TEMP_AMBIENT:
+ ret = olpc_ec_cmd(EC_AMB_TEMP, NULL, 0, (void *)&ec_word, 2);
+ if (ret)
+ return ret;
+
+ ec_word = be16_to_cpu(ec_word);
+ val->intval = ec_word * 100 / 256;
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ return ret;
+}
+
+static enum power_supply_property olpc_bat_props[] = {
+ POWER_SUPPLY_PROP_STATUS,
+ POWER_SUPPLY_PROP_PRESENT,
+ POWER_SUPPLY_PROP_HEALTH,
+ POWER_SUPPLY_PROP_TECHNOLOGY,
+ POWER_SUPPLY_PROP_VOLTAGE_AVG,
+ POWER_SUPPLY_PROP_CURRENT_AVG,
+ POWER_SUPPLY_PROP_CAPACITY,
+ POWER_SUPPLY_PROP_CAPACITY_LEVEL,
+ POWER_SUPPLY_PROP_TEMP,
+ POWER_SUPPLY_PROP_TEMP_AMBIENT,
+ POWER_SUPPLY_PROP_MANUFACTURER,
+};
+
+/*********************************************************************
+ * Initialisation
+ *********************************************************************/
+
+static struct platform_device *bat_pdev;
+
+static struct power_supply olpc_bat = {
+ .properties = olpc_bat_props,
+ .num_properties = ARRAY_SIZE(olpc_bat_props),
+ .get_property = olpc_bat_get_property,
+ .use_for_apm = 1,
+};
+
+void olpc_battery_trigger_uevent(unsigned long cause)
+{
+ if (cause & EC_SCI_SRC_ACPWR)
+ kobject_uevent(&olpc_ac.dev->kobj, KOBJ_CHANGE);
+ if (cause & (EC_SCI_SRC_BATERR|EC_SCI_SRC_BATSOC|EC_SCI_SRC_BATTERY))
+ kobject_uevent(&olpc_bat.dev->kobj, KOBJ_CHANGE);
+}
+
+static int __init olpc_bat_init(void)
+{
+ int ret = 0;
+ uint8_t status;
+
+ if (!olpc_platform_info.ecver)
+ return -ENXIO;
+ if (olpc_platform_info.ecver < 0x43) {
+ printk(KERN_NOTICE "OLPC EC version 0x%02x too old for battery driver.\n", olpc_platform_info.ecver);
+ return -ENXIO;
+ }
+
+ ret = olpc_ec_cmd(EC_BAT_STATUS, NULL, 0, &status, 1);
+ if (ret)
+ return ret;
+
+ /* Ignore the status. It doesn't actually matter */
+
+ bat_pdev = platform_device_register_simple("olpc-battery", 0, NULL, 0);
+ if (IS_ERR(bat_pdev))
+ return PTR_ERR(bat_pdev);
+
+ ret = power_supply_register(&bat_pdev->dev, &olpc_ac);
+ if (ret)
+ goto ac_failed;
+
+ olpc_bat.name = bat_pdev->name;
+
+ ret = power_supply_register(&bat_pdev->dev, &olpc_bat);
+ if (ret)
+ goto battery_failed;
+
+ olpc_register_battery_callback(&olpc_battery_trigger_uevent);
+ goto success;
+
+battery_failed:
+ power_supply_unregister(&olpc_ac);
+ac_failed:
+ platform_device_unregister(bat_pdev);
+success:
+ return ret;
+}
+
+static void __exit olpc_bat_exit(void)
+{
+ olpc_deregister_battery_callback();
+ power_supply_unregister(&olpc_bat);
+ power_supply_unregister(&olpc_ac);
+ platform_device_unregister(bat_pdev);
+ return;
+}
+
+module_init(olpc_bat_init);
+module_exit(olpc_bat_exit);
+
+MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Battery driver for One Laptop Per Child 'XO' machine");
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