diff options
Diffstat (limited to 'drivers/power/supply/macsmc_power.c')
| -rw-r--r-- | drivers/power/supply/macsmc_power.c | 516 |
1 files changed, 516 insertions, 0 deletions
diff --git a/drivers/power/supply/macsmc_power.c b/drivers/power/supply/macsmc_power.c new file mode 100644 index 000000000000..dee48ee8b5a4 --- /dev/null +++ b/drivers/power/supply/macsmc_power.c @@ -0,0 +1,516 @@ +// SPDX-License-Identifier: GPL-2.0-only OR MIT +/* + * Apple SMC Power/Battery Management + * Copyright The Asahi Linux Contributors + */ + +#include <linux/ctype.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/mfd/core.h> +#include <linux/mfd/macsmc.h> +#include <linux/power_supply.h> + +#define MAX_STRING_LENGTH 256 + +struct macsmc_power { + struct device *dev; + struct apple_smc *smc; + + struct power_supply *batt; + char model_name[MAX_STRING_LENGTH]; + char serial_number[MAX_STRING_LENGTH]; + char mfg_date[MAX_STRING_LENGTH]; + + struct power_supply *ac; + + struct notifier_block nb; +}; + +#define CHNC_BATTERY_FULL BIT(0) +#define CHNC_NO_CHARGER BIT(7) +#define CHNC_NOCHG_CH0C BIT(14) +#define CHNC_NOCHG_CH0B_CH0K BIT(15) +#define CHNC_BATTERY_FULL_2 BIT(18) +#define CHNC_BMS_BUSY BIT(23) +#define CHNC_NOAC_CH0J BIT(53) +#define CHNC_NOAC_CH0I BIT(54) + +#define CH0R_LOWER_FLAGS GENMASK(15, 0) +#define CH0R_NOAC_CH0I BIT(0) +#define CH0R_NOAC_CH0J BIT(5) +#define CH0R_BMS_BUSY BIT(8) +#define CH0R_NOAC_CH0K BIT(9) + +#define CH0X_CH0C BIT(0) +#define CH0X_CH0B BIT(1) + +static int macsmc_battery_get_status(struct macsmc_power *power) +{ + u64 nocharge_flags; + u32 nopower_flags; + u16 ac_current; + int ret; + + /* + * Note: there are fallbacks in case some of these SMC keys disappear in the future + * or are not present on some machines. We treat the absence of the CHCE/CHCC/BSFC/CHSC + * flags as an error, since they are quite fundamental and simple booleans. + */ + + /* + * If power input is inhibited, we are definitely discharging. + * However, if the only reason is the BMS is doing a balancing cycle, + * go ahead and ignore that one to avoid spooking users. + */ + ret = apple_smc_read_u32(power->smc, SMC_KEY(CH0R), &nopower_flags); + if (!ret && (nopower_flags & CH0R_LOWER_FLAGS & ~CH0R_BMS_BUSY)) + return POWER_SUPPLY_STATUS_DISCHARGING; + + /* If no charger is present, we are definitely discharging. */ + ret = apple_smc_read_flag(power->smc, SMC_KEY(CHCE)); + if (ret < 0) + return ret; + else if (!ret) + return POWER_SUPPLY_STATUS_DISCHARGING; + + /* If AC is not charge capable, we are definitely discharging. */ + ret = apple_smc_read_flag(power->smc, SMC_KEY(CHCC)); + if (ret < 0) + return ret; + else if (!ret) + return POWER_SUPPLY_STATUS_DISCHARGING; + + /* + * If the AC input current limit is tiny or 0, we are discharging no matter + * how much the BMS believes it can charge. + */ + ret = apple_smc_read_u16(power->smc, SMC_KEY(AC-i), &ac_current); + if (!ret && ac_current < 100) + return POWER_SUPPLY_STATUS_DISCHARGING; + + /* If the battery is full, report it as such. */ + ret = apple_smc_read_flag(power->smc, SMC_KEY(BSFC)); + if (ret < 0) + return ret; + else if (ret) + return POWER_SUPPLY_STATUS_FULL; + + /* If there are reasons we aren't charging... */ + ret = apple_smc_read_u64(power->smc, SMC_KEY(CHNC), &nocharge_flags); + if (!ret) { + /* Perhaps the battery is full after all */ + if (nocharge_flags & CHNC_BATTERY_FULL) + return POWER_SUPPLY_STATUS_FULL; + /* Or maybe the BMS is just busy doing something, if so call it charging anyway */ + else if (nocharge_flags == CHNC_BMS_BUSY) + return POWER_SUPPLY_STATUS_CHARGING; + /* If we have other reasons we aren't charging, say we aren't */ + else if (nocharge_flags) + return POWER_SUPPLY_STATUS_NOT_CHARGING; + /* Else we're either charging or about to charge */ + else + return POWER_SUPPLY_STATUS_CHARGING; + } + + /* As a fallback, use the system charging flag. */ + ret = apple_smc_read_flag(power->smc, SMC_KEY(CHSC)); + if (ret < 0) + return ret; + if (!ret) + return POWER_SUPPLY_STATUS_NOT_CHARGING; + else + return POWER_SUPPLY_STATUS_CHARGING; +} + +static int macsmc_battery_get_charge_behaviour(struct macsmc_power *power) +{ + int ret; + u8 val; + + /* CH0I returns a bitmask like the low byte of CH0R */ + ret = apple_smc_read_u8(power->smc, SMC_KEY(CH0I), &val); + if (ret) + return ret; + if (val & CH0R_NOAC_CH0I) + return POWER_SUPPLY_CHARGE_BEHAVIOUR_FORCE_DISCHARGE; + + /* CH0C returns a bitmask containing CH0B/CH0C flags */ + ret = apple_smc_read_u8(power->smc, SMC_KEY(CH0C), &val); + if (ret) + return ret; + if (val & CH0X_CH0C) + return POWER_SUPPLY_CHARGE_BEHAVIOUR_INHIBIT_CHARGE; + else + return POWER_SUPPLY_CHARGE_BEHAVIOUR_AUTO; +} + +static int macsmc_battery_set_charge_behaviour(struct macsmc_power *power, int val) +{ + u8 ch0i, ch0c; + int ret; + + /* + * CH0I/CH0C are "hard" controls that will allow the battery to run down to 0. + * CH0K/CH0B are "soft" controls that are reset to 0 when SOC drops below 50%; + * we don't expose these yet. + */ + + switch (val) { + case POWER_SUPPLY_CHARGE_BEHAVIOUR_AUTO: + ch0i = ch0c = 0; + break; + case POWER_SUPPLY_CHARGE_BEHAVIOUR_INHIBIT_CHARGE: + ch0i = 0; + ch0c = 1; + break; + case POWER_SUPPLY_CHARGE_BEHAVIOUR_FORCE_DISCHARGE: + ch0i = 1; + ch0c = 0; + break; + default: + return -EINVAL; + } + + ret = apple_smc_write_u8(power->smc, SMC_KEY(CH0I), ch0i); + if (ret) + return ret; + return apple_smc_write_u8(power->smc, SMC_KEY(CH0C), ch0c); +} + +static int macsmc_battery_get_date(const char *s, int *out) +{ + if (!isdigit(s[0]) || !isdigit(s[1])) + return -ENOTSUPP; + + *out = (s[0] - '0') * 10 + s[1] - '0'; + return 0; +} + +static int macsmc_battery_get_property(struct power_supply *psy, + enum power_supply_property psp, + union power_supply_propval *val) +{ + struct macsmc_power *power = power_supply_get_drvdata(psy); + int ret = 0; + u8 vu8; + u16 vu16; + u32 vu32; + s16 vs16; + s32 vs32; + s64 vs64; + + switch (psp) { + case POWER_SUPPLY_PROP_STATUS: + val->intval = macsmc_battery_get_status(power); + ret = val->intval < 0 ? val->intval : 0; + break; + case POWER_SUPPLY_PROP_PRESENT: + val->intval = 1; + break; + case POWER_SUPPLY_PROP_CHARGE_BEHAVIOUR: + val->intval = macsmc_battery_get_charge_behaviour(power); + ret = val->intval < 0 ? val->intval : 0; + break; + case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW: + ret = apple_smc_read_u16(power->smc, SMC_KEY(B0TE), &vu16); + val->intval = vu16 == 0xffff ? 0 : vu16 * 60; + break; + case POWER_SUPPLY_PROP_TIME_TO_FULL_NOW: + ret = apple_smc_read_u16(power->smc, SMC_KEY(B0TF), &vu16); + val->intval = vu16 == 0xffff ? 0 : vu16 * 60; + break; + case POWER_SUPPLY_PROP_CAPACITY: + ret = apple_smc_read_u8(power->smc, SMC_KEY(BUIC), &vu8); + val->intval = vu8; + break; + case POWER_SUPPLY_PROP_VOLTAGE_NOW: + ret = apple_smc_read_u16(power->smc, SMC_KEY(B0AV), &vu16); + val->intval = vu16 * 1000; + break; + case POWER_SUPPLY_PROP_CURRENT_NOW: + ret = apple_smc_read_s16(power->smc, SMC_KEY(B0AC), &vs16); + val->intval = vs16 * 1000; + break; + case POWER_SUPPLY_PROP_POWER_NOW: + ret = apple_smc_read_s32(power->smc, SMC_KEY(B0AP), &vs32); + val->intval = vs32 * 1000; + break; + case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN: + ret = apple_smc_read_u16(power->smc, SMC_KEY(BITV), &vu16); + val->intval = vu16 * 1000; + break; + case POWER_SUPPLY_PROP_CHARGE_TERM_CURRENT: + ret = apple_smc_read_u16(power->smc, SMC_KEY(B0RC), &vu16); + val->intval = vu16 * 1000; + break; + case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT: + ret = apple_smc_read_u32(power->smc, SMC_KEY(CSIL), &vu32); + val->intval = vu32 * 1000; + break; + case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX: + ret = apple_smc_read_u16(power->smc, SMC_KEY(B0RI), &vu16); + val->intval = vu16 * 1000; + break; + case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE: + ret = apple_smc_read_u16(power->smc, SMC_KEY(B0RV), &vu16); + val->intval = vu16 * 1000; + break; + case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN: + ret = apple_smc_read_u16(power->smc, SMC_KEY(B0DC), &vu16); + val->intval = vu16 * 1000; + break; + case POWER_SUPPLY_PROP_CHARGE_FULL: + ret = apple_smc_read_u16(power->smc, SMC_KEY(B0FC), &vu16); + val->intval = vu16 * 1000; + break; + case POWER_SUPPLY_PROP_CHARGE_NOW: + ret = apple_smc_read_u16(power->smc, SMC_KEY(B0RM), &vu16); + val->intval = swab16(vu16) * 1000; + break; + case POWER_SUPPLY_PROP_TEMP: + ret = apple_smc_read_u16(power->smc, SMC_KEY(B0AT), &vu16); + val->intval = vu16 - 2732; + break; + case POWER_SUPPLY_PROP_CHARGE_COUNTER: + ret = apple_smc_read_s64(power->smc, SMC_KEY(BAAC), &vs64); + val->intval = vs64; + break; + case POWER_SUPPLY_PROP_CYCLE_COUNT: + ret = apple_smc_read_u16(power->smc, SMC_KEY(B0CT), &vu16); + val->intval = vu16; + break; + case POWER_SUPPLY_PROP_SCOPE: + val->intval = POWER_SUPPLY_SCOPE_SYSTEM; + break; + case POWER_SUPPLY_PROP_HEALTH: + ret = apple_smc_read_flag(power->smc, SMC_KEY(BBAD)); + val->intval = ret == 1 ? POWER_SUPPLY_HEALTH_DEAD : POWER_SUPPLY_HEALTH_GOOD; + ret = ret < 0 ? ret : 0; + break; + case POWER_SUPPLY_PROP_MODEL_NAME: + val->strval = power->model_name; + break; + case POWER_SUPPLY_PROP_SERIAL_NUMBER: + val->strval = power->serial_number; + break; + case POWER_SUPPLY_PROP_MANUFACTURE_YEAR: + ret = macsmc_battery_get_date(&power->mfg_date[0], &val->intval); + val->intval += 2000 - 8; /* -8 is a fixup for a firmware bug... */ + break; + case POWER_SUPPLY_PROP_MANUFACTURE_MONTH: + ret = macsmc_battery_get_date(&power->mfg_date[2], &val->intval); + break; + case POWER_SUPPLY_PROP_MANUFACTURE_DAY: + ret = macsmc_battery_get_date(&power->mfg_date[4], &val->intval); + break; + default: + return -EINVAL; + } + + return ret; +} + +static int macsmc_battery_set_property(struct power_supply *psy, + enum power_supply_property psp, + const union power_supply_propval *val) +{ + struct macsmc_power *power = power_supply_get_drvdata(psy); + + switch (psp) { + case POWER_SUPPLY_PROP_CHARGE_BEHAVIOUR: + return macsmc_battery_set_charge_behaviour(power, val->intval); + default: + return -EINVAL; + } +} + +static int macsmc_battery_property_is_writeable(struct power_supply *psy, + enum power_supply_property psp) +{ + switch (psp) { + case POWER_SUPPLY_PROP_CHARGE_BEHAVIOUR: + return true; + default: + return false; + } +} + +static enum power_supply_property macsmc_battery_props[] = { + POWER_SUPPLY_PROP_STATUS, + POWER_SUPPLY_PROP_PRESENT, + POWER_SUPPLY_PROP_CHARGE_BEHAVIOUR, + POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW, + POWER_SUPPLY_PROP_TIME_TO_FULL_NOW, + POWER_SUPPLY_PROP_CAPACITY, + POWER_SUPPLY_PROP_VOLTAGE_NOW, + POWER_SUPPLY_PROP_CURRENT_NOW, + POWER_SUPPLY_PROP_POWER_NOW, + POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN, + POWER_SUPPLY_PROP_CHARGE_TERM_CURRENT, + POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT, + POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX, + POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE, + POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN, + POWER_SUPPLY_PROP_CHARGE_FULL, + POWER_SUPPLY_PROP_CHARGE_NOW, + POWER_SUPPLY_PROP_TEMP, + POWER_SUPPLY_PROP_CHARGE_COUNTER, + POWER_SUPPLY_PROP_CYCLE_COUNT, + POWER_SUPPLY_PROP_SCOPE, + POWER_SUPPLY_PROP_HEALTH, + POWER_SUPPLY_PROP_MODEL_NAME, + POWER_SUPPLY_PROP_SERIAL_NUMBER, + POWER_SUPPLY_PROP_MANUFACTURE_YEAR, + POWER_SUPPLY_PROP_MANUFACTURE_MONTH, + POWER_SUPPLY_PROP_MANUFACTURE_DAY, +}; + +static const struct power_supply_desc macsmc_battery_desc = { + .name = "macsmc-battery", + .type = POWER_SUPPLY_TYPE_BATTERY, + .get_property = macsmc_battery_get_property, + .set_property = macsmc_battery_set_property, + .property_is_writeable = macsmc_battery_property_is_writeable, + .properties = macsmc_battery_props, + .num_properties = ARRAY_SIZE(macsmc_battery_props), +}; + +static int macsmc_ac_get_property(struct power_supply *psy, + enum power_supply_property psp, + union power_supply_propval *val) +{ + struct macsmc_power *power = power_supply_get_drvdata(psy); + int ret = 0; + u16 vu16; + u32 vu32; + + switch (psp) { + case POWER_SUPPLY_PROP_ONLINE: + ret = apple_smc_read_u32(power->smc, SMC_KEY(CHIS), &vu32); + val->intval = !!vu32; + break; + case POWER_SUPPLY_PROP_VOLTAGE_NOW: + ret = apple_smc_read_u16(power->smc, SMC_KEY(AC-n), &vu16); + val->intval = vu16 * 1000; + break; + case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT: + ret = apple_smc_read_u16(power->smc, SMC_KEY(AC-i), &vu16); + val->intval = vu16 * 1000; + break; + case POWER_SUPPLY_PROP_INPUT_POWER_LIMIT: + ret = apple_smc_read_u32(power->smc, SMC_KEY(ACPW), &vu32); + val->intval = vu32 * 1000; + break; + default: + return -EINVAL; + } + + return ret; +} + +static enum power_supply_property macsmc_ac_props[] = { + POWER_SUPPLY_PROP_ONLINE, + POWER_SUPPLY_PROP_VOLTAGE_NOW, + POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT, + POWER_SUPPLY_PROP_INPUT_POWER_LIMIT, +}; + +static const struct power_supply_desc macsmc_ac_desc = { + .name = "macsmc-ac", + .type = POWER_SUPPLY_TYPE_MAINS, + .get_property = macsmc_ac_get_property, + .properties = macsmc_ac_props, + .num_properties = ARRAY_SIZE(macsmc_ac_props), +}; + +static int macsmc_power_event(struct notifier_block *nb, unsigned long event, void *data) +{ + struct macsmc_power *power = container_of(nb, struct macsmc_power, nb); + + if ((event & 0xffffff00) == 0x71010100) { + bool charging = (event & 0xff) != 0; + + dev_info(power->dev, "Charging: %d\n", charging); + power_supply_changed(power->batt); + power_supply_changed(power->ac); + + return NOTIFY_OK; + } + + return NOTIFY_DONE; +} + +static int macsmc_power_probe(struct platform_device *pdev) +{ + struct apple_smc *smc = dev_get_drvdata(pdev->dev.parent); + struct power_supply_config psy_cfg = {}; + struct macsmc_power *power; + int ret; + + power = devm_kzalloc(&pdev->dev, sizeof(*power), GFP_KERNEL); + if (!power) + return -ENOMEM; + + power->dev = &pdev->dev; + power->smc = smc; + dev_set_drvdata(&pdev->dev, power); + + /* Ignore devices without a charger/battery */ + if (macsmc_battery_get_status(power) <= POWER_SUPPLY_STATUS_UNKNOWN) + return -ENODEV; + + /* Fetch string properties */ + apple_smc_read(smc, SMC_KEY(BMDN), power->model_name, sizeof(power->model_name) - 1); + apple_smc_read(smc, SMC_KEY(BMSN), power->serial_number, sizeof(power->serial_number) - 1); + apple_smc_read(smc, SMC_KEY(BMDT), power->mfg_date, sizeof(power->mfg_date) - 1); + + /* Turn off the "optimized battery charging" flags, in case macOS left them on */ + apple_smc_write_u8(power->smc, SMC_KEY(CH0K), 0); + apple_smc_write_u8(power->smc, SMC_KEY(CH0B), 0); + + psy_cfg.drv_data = power; + power->batt = devm_power_supply_register(&pdev->dev, &macsmc_battery_desc, &psy_cfg); + if (IS_ERR(power->batt)) { + dev_err(&pdev->dev, "Failed to register battery\n"); + ret = PTR_ERR(power->batt); + return ret; + } + + power->ac = devm_power_supply_register(&pdev->dev, &macsmc_ac_desc, &psy_cfg); + if (IS_ERR(power->ac)) { + dev_err(&pdev->dev, "Failed to register AC adapter\n"); + ret = PTR_ERR(power->ac); + return ret; + } + + power->nb.notifier_call = macsmc_power_event; + apple_smc_register_notifier(power->smc, &power->nb); + + return 0; +} + +static int macsmc_power_remove(struct platform_device *pdev) +{ + struct macsmc_power *power = dev_get_drvdata(&pdev->dev); + + apple_smc_unregister_notifier(power->smc, &power->nb); + + return 0; +} + +static struct platform_driver macsmc_power_driver = { + .driver = { + .name = "macsmc-power", + .owner = THIS_MODULE, + }, + .probe = macsmc_power_probe, + .remove = macsmc_power_remove, +}; +module_platform_driver(macsmc_power_driver); + +MODULE_LICENSE("Dual MIT/GPL"); +MODULE_DESCRIPTION("Apple SMC battery and power management driver"); +MODULE_AUTHOR("Hector Martin <marcan@marcan.st>"); +MODULE_ALIAS("platform:macsmc-power"); |