diff options
Diffstat (limited to 'drivers/power/supply/lp8788-charger.c')
| -rw-r--r-- | drivers/power/supply/lp8788-charger.c | 741 |
1 files changed, 741 insertions, 0 deletions
diff --git a/drivers/power/supply/lp8788-charger.c b/drivers/power/supply/lp8788-charger.c new file mode 100644 index 000000000..397e5a03b --- /dev/null +++ b/drivers/power/supply/lp8788-charger.c @@ -0,0 +1,741 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * TI LP8788 MFD - battery charger driver + * + * Copyright 2012 Texas Instruments + * + * Author: Milo(Woogyom) Kim <milo.kim@ti.com> + */ + +#include <linux/err.h> +#include <linux/iio/consumer.h> +#include <linux/interrupt.h> +#include <linux/irqdomain.h> +#include <linux/mfd/lp8788.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/power_supply.h> +#include <linux/slab.h> +#include <linux/workqueue.h> + +/* register address */ +#define LP8788_CHG_STATUS 0x07 +#define LP8788_CHG_IDCIN 0x13 +#define LP8788_CHG_IBATT 0x14 +#define LP8788_CHG_VTERM 0x15 +#define LP8788_CHG_EOC 0x16 + +/* mask/shift bits */ +#define LP8788_CHG_INPUT_STATE_M 0x03 /* Addr 07h */ +#define LP8788_CHG_STATE_M 0x3C +#define LP8788_CHG_STATE_S 2 +#define LP8788_NO_BATT_M BIT(6) +#define LP8788_BAD_BATT_M BIT(7) +#define LP8788_CHG_IBATT_M 0x1F /* Addr 14h */ +#define LP8788_CHG_VTERM_M 0x0F /* Addr 15h */ +#define LP8788_CHG_EOC_LEVEL_M 0x30 /* Addr 16h */ +#define LP8788_CHG_EOC_LEVEL_S 4 +#define LP8788_CHG_EOC_TIME_M 0x0E +#define LP8788_CHG_EOC_TIME_S 1 +#define LP8788_CHG_EOC_MODE_M BIT(0) + +#define LP8788_CHARGER_NAME "charger" +#define LP8788_BATTERY_NAME "main_batt" + +#define LP8788_CHG_START 0x11 +#define LP8788_CHG_END 0x1C + +#define LP8788_ISEL_MAX 23 +#define LP8788_ISEL_STEP 50 +#define LP8788_VTERM_MIN 4100 +#define LP8788_VTERM_STEP 25 +#define LP8788_MAX_BATT_CAPACITY 100 +#define LP8788_MAX_CHG_IRQS 11 + +enum lp8788_charging_state { + LP8788_OFF, + LP8788_WARM_UP, + LP8788_LOW_INPUT = 0x3, + LP8788_PRECHARGE, + LP8788_CC, + LP8788_CV, + LP8788_MAINTENANCE, + LP8788_BATTERY_FAULT, + LP8788_SYSTEM_SUPPORT = 0xC, + LP8788_HIGH_CURRENT = 0xF, + LP8788_MAX_CHG_STATE, +}; + +enum lp8788_charger_adc_sel { + LP8788_VBATT, + LP8788_BATT_TEMP, + LP8788_NUM_CHG_ADC, +}; + +enum lp8788_charger_input_state { + LP8788_SYSTEM_SUPPLY = 1, + LP8788_FULL_FUNCTION, +}; + +/* + * struct lp8788_chg_irq + * @which : lp8788 interrupt id + * @virq : Linux IRQ number from irq_domain + */ +struct lp8788_chg_irq { + enum lp8788_int_id which; + int virq; +}; + +/* + * struct lp8788_charger + * @lp : used for accessing the registers of mfd lp8788 device + * @charger : power supply driver for the battery charger + * @battery : power supply driver for the battery + * @charger_work : work queue for charger input interrupts + * @chan : iio channels for getting adc values + * eg) battery voltage, capacity and temperature + * @irqs : charger dedicated interrupts + * @num_irqs : total numbers of charger interrupts + * @pdata : charger platform specific data + */ +struct lp8788_charger { + struct lp8788 *lp; + struct power_supply *charger; + struct power_supply *battery; + struct work_struct charger_work; + struct iio_channel *chan[LP8788_NUM_CHG_ADC]; + struct lp8788_chg_irq irqs[LP8788_MAX_CHG_IRQS]; + int num_irqs; + struct lp8788_charger_platform_data *pdata; +}; + +static char *battery_supplied_to[] = { + LP8788_BATTERY_NAME, +}; + +static enum power_supply_property lp8788_charger_prop[] = { + POWER_SUPPLY_PROP_ONLINE, + POWER_SUPPLY_PROP_CURRENT_MAX, +}; + +static enum power_supply_property lp8788_battery_prop[] = { + POWER_SUPPLY_PROP_STATUS, + POWER_SUPPLY_PROP_HEALTH, + POWER_SUPPLY_PROP_PRESENT, + POWER_SUPPLY_PROP_VOLTAGE_NOW, + POWER_SUPPLY_PROP_CAPACITY, + POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT, + POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX, + POWER_SUPPLY_PROP_TEMP, +}; + +static bool lp8788_is_charger_detected(struct lp8788_charger *pchg) +{ + u8 data; + + lp8788_read_byte(pchg->lp, LP8788_CHG_STATUS, &data); + data &= LP8788_CHG_INPUT_STATE_M; + + return data == LP8788_SYSTEM_SUPPLY || data == LP8788_FULL_FUNCTION; +} + +static int lp8788_charger_get_property(struct power_supply *psy, + enum power_supply_property psp, + union power_supply_propval *val) +{ + struct lp8788_charger *pchg = dev_get_drvdata(psy->dev.parent); + u8 read; + + switch (psp) { + case POWER_SUPPLY_PROP_ONLINE: + val->intval = lp8788_is_charger_detected(pchg); + break; + case POWER_SUPPLY_PROP_CURRENT_MAX: + lp8788_read_byte(pchg->lp, LP8788_CHG_IDCIN, &read); + val->intval = LP8788_ISEL_STEP * + (min_t(int, read, LP8788_ISEL_MAX) + 1); + break; + default: + return -EINVAL; + } + + return 0; +} + +static int lp8788_get_battery_status(struct lp8788_charger *pchg, + union power_supply_propval *val) +{ + enum lp8788_charging_state state; + u8 data; + int ret; + + ret = lp8788_read_byte(pchg->lp, LP8788_CHG_STATUS, &data); + if (ret) + return ret; + + state = (data & LP8788_CHG_STATE_M) >> LP8788_CHG_STATE_S; + switch (state) { + case LP8788_OFF: + val->intval = POWER_SUPPLY_STATUS_DISCHARGING; + break; + case LP8788_PRECHARGE: + case LP8788_CC: + case LP8788_CV: + case LP8788_HIGH_CURRENT: + val->intval = POWER_SUPPLY_STATUS_CHARGING; + break; + case LP8788_MAINTENANCE: + val->intval = POWER_SUPPLY_STATUS_FULL; + break; + default: + val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING; + break; + } + + return 0; +} + +static int lp8788_get_battery_health(struct lp8788_charger *pchg, + union power_supply_propval *val) +{ + u8 data; + int ret; + + ret = lp8788_read_byte(pchg->lp, LP8788_CHG_STATUS, &data); + if (ret) + return ret; + + if (data & LP8788_NO_BATT_M) + val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE; + else if (data & LP8788_BAD_BATT_M) + val->intval = POWER_SUPPLY_HEALTH_DEAD; + else + val->intval = POWER_SUPPLY_HEALTH_GOOD; + + return 0; +} + +static int lp8788_get_battery_present(struct lp8788_charger *pchg, + union power_supply_propval *val) +{ + u8 data; + int ret; + + ret = lp8788_read_byte(pchg->lp, LP8788_CHG_STATUS, &data); + if (ret) + return ret; + + val->intval = !(data & LP8788_NO_BATT_M); + return 0; +} + +static int lp8788_get_vbatt_adc(struct lp8788_charger *pchg, int *result) +{ + struct iio_channel *channel = pchg->chan[LP8788_VBATT]; + + if (!channel) + return -EINVAL; + + return iio_read_channel_processed(channel, result); +} + +static int lp8788_get_battery_voltage(struct lp8788_charger *pchg, + union power_supply_propval *val) +{ + return lp8788_get_vbatt_adc(pchg, &val->intval); +} + +static int lp8788_get_battery_capacity(struct lp8788_charger *pchg, + union power_supply_propval *val) +{ + struct lp8788 *lp = pchg->lp; + struct lp8788_charger_platform_data *pdata = pchg->pdata; + unsigned int max_vbatt; + int vbatt; + enum lp8788_charging_state state; + u8 data; + int ret; + + if (!pdata) + return -EINVAL; + + max_vbatt = pdata->max_vbatt_mv; + if (max_vbatt == 0) + return -EINVAL; + + ret = lp8788_read_byte(lp, LP8788_CHG_STATUS, &data); + if (ret) + return ret; + + state = (data & LP8788_CHG_STATE_M) >> LP8788_CHG_STATE_S; + + if (state == LP8788_MAINTENANCE) { + val->intval = LP8788_MAX_BATT_CAPACITY; + } else { + ret = lp8788_get_vbatt_adc(pchg, &vbatt); + if (ret) + return ret; + + val->intval = (vbatt * LP8788_MAX_BATT_CAPACITY) / max_vbatt; + val->intval = min(val->intval, LP8788_MAX_BATT_CAPACITY); + } + + return 0; +} + +static int lp8788_get_battery_temperature(struct lp8788_charger *pchg, + union power_supply_propval *val) +{ + struct iio_channel *channel = pchg->chan[LP8788_BATT_TEMP]; + int result; + int ret; + + if (!channel) + return -EINVAL; + + ret = iio_read_channel_processed(channel, &result); + if (ret < 0) + return -EINVAL; + + /* unit: 0.1 'C */ + val->intval = result * 10; + + return 0; +} + +static int lp8788_get_battery_charging_current(struct lp8788_charger *pchg, + union power_supply_propval *val) +{ + u8 read; + + lp8788_read_byte(pchg->lp, LP8788_CHG_IBATT, &read); + read &= LP8788_CHG_IBATT_M; + val->intval = LP8788_ISEL_STEP * + (min_t(int, read, LP8788_ISEL_MAX) + 1); + + return 0; +} + +static int lp8788_get_charging_termination_voltage(struct lp8788_charger *pchg, + union power_supply_propval *val) +{ + u8 read; + + lp8788_read_byte(pchg->lp, LP8788_CHG_VTERM, &read); + read &= LP8788_CHG_VTERM_M; + val->intval = LP8788_VTERM_MIN + LP8788_VTERM_STEP * read; + + return 0; +} + +static int lp8788_battery_get_property(struct power_supply *psy, + enum power_supply_property psp, + union power_supply_propval *val) +{ + struct lp8788_charger *pchg = dev_get_drvdata(psy->dev.parent); + + switch (psp) { + case POWER_SUPPLY_PROP_STATUS: + return lp8788_get_battery_status(pchg, val); + case POWER_SUPPLY_PROP_HEALTH: + return lp8788_get_battery_health(pchg, val); + case POWER_SUPPLY_PROP_PRESENT: + return lp8788_get_battery_present(pchg, val); + case POWER_SUPPLY_PROP_VOLTAGE_NOW: + return lp8788_get_battery_voltage(pchg, val); + case POWER_SUPPLY_PROP_CAPACITY: + return lp8788_get_battery_capacity(pchg, val); + case POWER_SUPPLY_PROP_TEMP: + return lp8788_get_battery_temperature(pchg, val); + case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT: + return lp8788_get_battery_charging_current(pchg, val); + case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX: + return lp8788_get_charging_termination_voltage(pchg, val); + default: + return -EINVAL; + } +} + +static inline bool lp8788_is_valid_charger_register(u8 addr) +{ + return addr >= LP8788_CHG_START && addr <= LP8788_CHG_END; +} + +static int lp8788_update_charger_params(struct platform_device *pdev, + struct lp8788_charger *pchg) +{ + struct lp8788 *lp = pchg->lp; + struct lp8788_charger_platform_data *pdata = pchg->pdata; + struct lp8788_chg_param *param; + int i; + int ret; + + if (!pdata || !pdata->chg_params) { + dev_info(&pdev->dev, "skip updating charger parameters\n"); + return 0; + } + + /* settting charging parameters */ + for (i = 0; i < pdata->num_chg_params; i++) { + param = pdata->chg_params + i; + + if (lp8788_is_valid_charger_register(param->addr)) { + ret = lp8788_write_byte(lp, param->addr, param->val); + if (ret) + return ret; + } + } + + return 0; +} + +static const struct power_supply_desc lp8788_psy_charger_desc = { + .name = LP8788_CHARGER_NAME, + .type = POWER_SUPPLY_TYPE_MAINS, + .properties = lp8788_charger_prop, + .num_properties = ARRAY_SIZE(lp8788_charger_prop), + .get_property = lp8788_charger_get_property, +}; + +static const struct power_supply_desc lp8788_psy_battery_desc = { + .name = LP8788_BATTERY_NAME, + .type = POWER_SUPPLY_TYPE_BATTERY, + .properties = lp8788_battery_prop, + .num_properties = ARRAY_SIZE(lp8788_battery_prop), + .get_property = lp8788_battery_get_property, +}; + +static void lp8788_psy_unregister(struct lp8788_charger *pchg) +{ + power_supply_unregister(pchg->battery); + power_supply_unregister(pchg->charger); +} + +static void lp8788_charger_event(struct work_struct *work) +{ + struct lp8788_charger *pchg = + container_of(work, struct lp8788_charger, charger_work); + struct lp8788_charger_platform_data *pdata = pchg->pdata; + enum lp8788_charger_event event = lp8788_is_charger_detected(pchg); + + pdata->charger_event(pchg->lp, event); +} + +static bool lp8788_find_irq_id(struct lp8788_charger *pchg, int virq, int *id) +{ + bool found = false; + int i; + + for (i = 0; i < pchg->num_irqs; i++) { + if (pchg->irqs[i].virq == virq) { + *id = pchg->irqs[i].which; + found = true; + break; + } + } + + return found; +} + +static irqreturn_t lp8788_charger_irq_thread(int virq, void *ptr) +{ + struct lp8788_charger *pchg = ptr; + struct lp8788_charger_platform_data *pdata = pchg->pdata; + int id = -1; + + if (!lp8788_find_irq_id(pchg, virq, &id)) + return IRQ_NONE; + + switch (id) { + case LP8788_INT_CHG_INPUT_STATE: + case LP8788_INT_CHG_STATE: + case LP8788_INT_EOC: + case LP8788_INT_BATT_LOW: + case LP8788_INT_NO_BATT: + power_supply_changed(pchg->charger); + power_supply_changed(pchg->battery); + break; + default: + break; + } + + /* report charger dectection event if used */ + if (!pdata) + goto irq_handled; + + if (pdata->charger_event && id == LP8788_INT_CHG_INPUT_STATE) + schedule_work(&pchg->charger_work); + +irq_handled: + return IRQ_HANDLED; +} + +static int lp8788_set_irqs(struct platform_device *pdev, + struct lp8788_charger *pchg, const char *name) +{ + struct resource *r; + struct irq_domain *irqdm = pchg->lp->irqdm; + int irq_start; + int irq_end; + int virq; + int nr_irq; + int i; + int ret; + + /* no error even if no irq resource */ + r = platform_get_resource_byname(pdev, IORESOURCE_IRQ, name); + if (!r) + return 0; + + irq_start = r->start; + irq_end = r->end; + + for (i = irq_start; i <= irq_end; i++) { + nr_irq = pchg->num_irqs; + + virq = irq_create_mapping(irqdm, i); + pchg->irqs[nr_irq].virq = virq; + pchg->irqs[nr_irq].which = i; + pchg->num_irqs++; + + ret = request_threaded_irq(virq, NULL, + lp8788_charger_irq_thread, + IRQF_ONESHOT, name, pchg); + if (ret) + break; + } + + if (i <= irq_end) + goto err_free_irq; + + return 0; + +err_free_irq: + for (i = 0; i < pchg->num_irqs; i++) + free_irq(pchg->irqs[i].virq, pchg); + return ret; +} + +static int lp8788_irq_register(struct platform_device *pdev, + struct lp8788_charger *pchg) +{ + const char *name[] = { + LP8788_CHG_IRQ, LP8788_PRSW_IRQ, LP8788_BATT_IRQ + }; + int i; + int ret; + + INIT_WORK(&pchg->charger_work, lp8788_charger_event); + pchg->num_irqs = 0; + + for (i = 0; i < ARRAY_SIZE(name); i++) { + ret = lp8788_set_irqs(pdev, pchg, name[i]); + if (ret) { + dev_warn(&pdev->dev, "irq setup failed: %s\n", name[i]); + return ret; + } + } + + if (pchg->num_irqs > LP8788_MAX_CHG_IRQS) { + dev_err(&pdev->dev, "invalid total number of irqs: %d\n", + pchg->num_irqs); + return -EINVAL; + } + + + return 0; +} + +static void lp8788_irq_unregister(struct platform_device *pdev, + struct lp8788_charger *pchg) +{ + int i; + int irq; + + for (i = 0; i < pchg->num_irqs; i++) { + irq = pchg->irqs[i].virq; + if (!irq) + continue; + + free_irq(irq, pchg); + } +} + +static void lp8788_setup_adc_channel(struct device *dev, + struct lp8788_charger *pchg) +{ + struct lp8788_charger_platform_data *pdata = pchg->pdata; + struct iio_channel *chan; + + if (!pdata) + return; + + /* ADC channel for battery voltage */ + chan = devm_iio_channel_get(dev, pdata->adc_vbatt); + pchg->chan[LP8788_VBATT] = IS_ERR(chan) ? NULL : chan; + + /* ADC channel for battery temperature */ + chan = devm_iio_channel_get(dev, pdata->adc_batt_temp); + pchg->chan[LP8788_BATT_TEMP] = IS_ERR(chan) ? NULL : chan; +} + +static ssize_t lp8788_show_charger_status(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct lp8788_charger *pchg = dev_get_drvdata(dev); + enum lp8788_charging_state state; + static const char * const desc[LP8788_MAX_CHG_STATE] = { + [LP8788_OFF] = "CHARGER OFF", + [LP8788_WARM_UP] = "WARM UP", + [LP8788_LOW_INPUT] = "LOW INPUT STATE", + [LP8788_PRECHARGE] = "CHARGING - PRECHARGE", + [LP8788_CC] = "CHARGING - CC", + [LP8788_CV] = "CHARGING - CV", + [LP8788_MAINTENANCE] = "NO CHARGING - MAINTENANCE", + [LP8788_BATTERY_FAULT] = "BATTERY FAULT", + [LP8788_SYSTEM_SUPPORT] = "SYSTEM SUPPORT", + [LP8788_HIGH_CURRENT] = "HIGH CURRENT", + }; + u8 data; + + lp8788_read_byte(pchg->lp, LP8788_CHG_STATUS, &data); + state = (data & LP8788_CHG_STATE_M) >> LP8788_CHG_STATE_S; + + return scnprintf(buf, PAGE_SIZE, "%s\n", desc[state]); +} + +static ssize_t lp8788_show_eoc_time(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct lp8788_charger *pchg = dev_get_drvdata(dev); + static const char * const stime[] = { + "400ms", "5min", "10min", "15min", + "20min", "25min", "30min", "No timeout" + }; + u8 val; + + lp8788_read_byte(pchg->lp, LP8788_CHG_EOC, &val); + val = (val & LP8788_CHG_EOC_TIME_M) >> LP8788_CHG_EOC_TIME_S; + + return scnprintf(buf, PAGE_SIZE, "End Of Charge Time: %s\n", + stime[val]); +} + +static ssize_t lp8788_show_eoc_level(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct lp8788_charger *pchg = dev_get_drvdata(dev); + static const char * const abs_level[] = { + "25mA", "49mA", "75mA", "98mA" + }; + static const char * const relative_level[] = { + "5%", "10%", "15%", "20%" + }; + const char *level; + u8 val; + u8 mode; + + lp8788_read_byte(pchg->lp, LP8788_CHG_EOC, &val); + + mode = val & LP8788_CHG_EOC_MODE_M; + val = (val & LP8788_CHG_EOC_LEVEL_M) >> LP8788_CHG_EOC_LEVEL_S; + level = mode ? abs_level[val] : relative_level[val]; + + return scnprintf(buf, PAGE_SIZE, "End Of Charge Level: %s\n", level); +} + +static DEVICE_ATTR(charger_status, S_IRUSR, lp8788_show_charger_status, NULL); +static DEVICE_ATTR(eoc_time, S_IRUSR, lp8788_show_eoc_time, NULL); +static DEVICE_ATTR(eoc_level, S_IRUSR, lp8788_show_eoc_level, NULL); + +static struct attribute *lp8788_charger_sysfs_attrs[] = { + &dev_attr_charger_status.attr, + &dev_attr_eoc_time.attr, + &dev_attr_eoc_level.attr, + NULL, +}; + +ATTRIBUTE_GROUPS(lp8788_charger_sysfs); + +static int lp8788_psy_register(struct platform_device *pdev, + struct lp8788_charger *pchg) +{ + struct power_supply_config charger_cfg = {}; + + charger_cfg.attr_grp = lp8788_charger_sysfs_groups; + charger_cfg.supplied_to = battery_supplied_to; + charger_cfg.num_supplicants = ARRAY_SIZE(battery_supplied_to); + + pchg->charger = power_supply_register(&pdev->dev, + &lp8788_psy_charger_desc, + &charger_cfg); + if (IS_ERR(pchg->charger)) + return -EPERM; + + pchg->battery = power_supply_register(&pdev->dev, + &lp8788_psy_battery_desc, NULL); + if (IS_ERR(pchg->battery)) { + power_supply_unregister(pchg->charger); + return -EPERM; + } + + return 0; +} + +static int lp8788_charger_probe(struct platform_device *pdev) +{ + struct lp8788 *lp = dev_get_drvdata(pdev->dev.parent); + struct lp8788_charger *pchg; + struct device *dev = &pdev->dev; + int ret; + + pchg = devm_kzalloc(dev, sizeof(struct lp8788_charger), GFP_KERNEL); + if (!pchg) + return -ENOMEM; + + pchg->lp = lp; + pchg->pdata = lp->pdata ? lp->pdata->chg_pdata : NULL; + platform_set_drvdata(pdev, pchg); + + ret = lp8788_update_charger_params(pdev, pchg); + if (ret) + return ret; + + lp8788_setup_adc_channel(&pdev->dev, pchg); + + ret = lp8788_psy_register(pdev, pchg); + if (ret) + return ret; + + ret = lp8788_irq_register(pdev, pchg); + if (ret) + dev_warn(dev, "failed to register charger irq: %d\n", ret); + + return 0; +} + +static int lp8788_charger_remove(struct platform_device *pdev) +{ + struct lp8788_charger *pchg = platform_get_drvdata(pdev); + + flush_work(&pchg->charger_work); + lp8788_irq_unregister(pdev, pchg); + lp8788_psy_unregister(pchg); + + return 0; +} + +static struct platform_driver lp8788_charger_driver = { + .probe = lp8788_charger_probe, + .remove = lp8788_charger_remove, + .driver = { + .name = LP8788_DEV_CHARGER, + }, +}; +module_platform_driver(lp8788_charger_driver); + +MODULE_DESCRIPTION("TI LP8788 Charger Driver"); +MODULE_AUTHOR("Milo Kim"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:lp8788-charger"); |