diff options
Diffstat (limited to 'drivers/power/twl4030_charger.c')
| -rw-r--r-- | drivers/power/twl4030_charger.c | 565 |
1 files changed, 565 insertions, 0 deletions
diff --git a/drivers/power/twl4030_charger.c b/drivers/power/twl4030_charger.c new file mode 100644 index 0000000..ff1f423 --- /dev/null +++ b/drivers/power/twl4030_charger.c @@ -0,0 +1,565 @@ +/* + * TWL4030/TPS65950 BCI (Battery Charger Interface) driver + * + * Copyright (C) 2010 Gražvydas Ignotas <notasas@gmail.com> + * + * based on twl4030_bci_battery.c by TI + * Copyright (C) 2008 Texas Instruments, Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/platform_device.h> +#include <linux/interrupt.h> +#include <linux/i2c/twl.h> +#include <linux/power_supply.h> +#include <linux/notifier.h> +#include <linux/usb/otg.h> + +#define TWL4030_BCIMSTATEC 0x02 +#define TWL4030_BCIICHG 0x08 +#define TWL4030_BCIVAC 0x0a +#define TWL4030_BCIVBUS 0x0c +#define TWL4030_BCIMFSTS4 0x10 +#define TWL4030_BCICTL1 0x23 + +#define TWL4030_BCIAUTOWEN BIT(5) +#define TWL4030_CONFIG_DONE BIT(4) +#define TWL4030_BCIAUTOUSB BIT(1) +#define TWL4030_BCIAUTOAC BIT(0) +#define TWL4030_CGAIN BIT(5) +#define TWL4030_USBFASTMCHG BIT(2) +#define TWL4030_STS_VBUS BIT(7) +#define TWL4030_STS_USB_ID BIT(2) + +/* BCI interrupts */ +#define TWL4030_WOVF BIT(0) /* Watchdog overflow */ +#define TWL4030_TMOVF BIT(1) /* Timer overflow */ +#define TWL4030_ICHGHIGH BIT(2) /* Battery charge current high */ +#define TWL4030_ICHGLOW BIT(3) /* Battery cc. low / FSM state change */ +#define TWL4030_ICHGEOC BIT(4) /* Battery current end-of-charge */ +#define TWL4030_TBATOR2 BIT(5) /* Battery temperature out of range 2 */ +#define TWL4030_TBATOR1 BIT(6) /* Battery temperature out of range 1 */ +#define TWL4030_BATSTS BIT(7) /* Battery status */ + +#define TWL4030_VBATLVL BIT(0) /* VBAT level */ +#define TWL4030_VBATOV BIT(1) /* VBAT overvoltage */ +#define TWL4030_VBUSOV BIT(2) /* VBUS overvoltage */ +#define TWL4030_ACCHGOV BIT(3) /* Ac charger overvoltage */ + +#define TWL4030_MSTATEC_USB BIT(4) +#define TWL4030_MSTATEC_AC BIT(5) +#define TWL4030_MSTATEC_MASK 0x0f +#define TWL4030_MSTATEC_QUICK1 0x02 +#define TWL4030_MSTATEC_QUICK7 0x07 +#define TWL4030_MSTATEC_COMPLETE1 0x0b +#define TWL4030_MSTATEC_COMPLETE4 0x0e + +static bool allow_usb; +module_param(allow_usb, bool, 1); +MODULE_PARM_DESC(allow_usb, "Allow USB charge drawing default current"); + +struct twl4030_bci { + struct device *dev; + struct power_supply ac; + struct power_supply usb; + struct otg_transceiver *transceiver; + struct notifier_block otg_nb; + int irq_chg; + int irq_bci; +}; + +/* + * clear and set bits on an given register on a given module + */ +static int twl4030_clear_set(u8 mod_no, u8 clear, u8 set, u8 reg) +{ + u8 val = 0; + int ret; + + ret = twl_i2c_read_u8(mod_no, &val, reg); + if (ret) + return ret; + + val &= ~clear; + val |= set; + + return twl_i2c_write_u8(mod_no, val, reg); +} + +static int twl4030_bci_read(u8 reg, u8 *val) +{ + return twl_i2c_read_u8(TWL4030_MODULE_MAIN_CHARGE, val, reg); +} + +static int twl4030_clear_set_boot_bci(u8 clear, u8 set) +{ + return twl4030_clear_set(TWL4030_MODULE_PM_MASTER, 0, + TWL4030_CONFIG_DONE | TWL4030_BCIAUTOWEN | set, + TWL4030_PM_MASTER_BOOT_BCI); +} + +static int twl4030bci_read_adc_val(u8 reg) +{ + int ret, temp; + u8 val; + + /* read MSB */ + ret = twl4030_bci_read(reg + 1, &val); + if (ret) + return ret; + + temp = (int)(val & 0x03) << 8; + + /* read LSB */ + ret = twl4030_bci_read(reg, &val); + if (ret) + return ret; + + return temp | val; +} + +/* + * Check if VBUS power is present + */ +static int twl4030_bci_have_vbus(struct twl4030_bci *bci) +{ + int ret; + u8 hwsts; + + ret = twl_i2c_read_u8(TWL4030_MODULE_PM_MASTER, &hwsts, + TWL4030_PM_MASTER_STS_HW_CONDITIONS); + if (ret < 0) + return 0; + + dev_dbg(bci->dev, "check_vbus: HW_CONDITIONS %02x\n", hwsts); + + /* in case we also have STS_USB_ID, VBUS is driven by TWL itself */ + if ((hwsts & TWL4030_STS_VBUS) && !(hwsts & TWL4030_STS_USB_ID)) + return 1; + + return 0; +} + +/* + * Enable/Disable USB Charge funtionality. + */ +static int twl4030_charger_enable_usb(struct twl4030_bci *bci, bool enable) +{ + int ret; + + if (enable) { + /* Check for USB charger conneted */ + if (!twl4030_bci_have_vbus(bci)) + return -ENODEV; + + /* + * Until we can find out what current the device can provide, + * require a module param to enable USB charging. + */ + if (!allow_usb) { + dev_warn(bci->dev, "USB charging is disabled.\n"); + return -EACCES; + } + + /* forcing the field BCIAUTOUSB (BOOT_BCI[1]) to 1 */ + ret = twl4030_clear_set_boot_bci(0, TWL4030_BCIAUTOUSB); + if (ret < 0) + return ret; + + /* forcing USBFASTMCHG(BCIMFSTS4[2]) to 1 */ + ret = twl4030_clear_set(TWL4030_MODULE_MAIN_CHARGE, 0, + TWL4030_USBFASTMCHG, TWL4030_BCIMFSTS4); + } else { + ret = twl4030_clear_set_boot_bci(TWL4030_BCIAUTOUSB, 0); + } + + return ret; +} + +/* + * Enable/Disable AC Charge funtionality. + */ +static int twl4030_charger_enable_ac(bool enable) +{ + int ret; + + if (enable) + ret = twl4030_clear_set_boot_bci(0, TWL4030_BCIAUTOAC); + else + ret = twl4030_clear_set_boot_bci(TWL4030_BCIAUTOAC, 0); + + return ret; +} + +/* + * TWL4030 CHG_PRES (AC charger presence) events + */ +static irqreturn_t twl4030_charger_interrupt(int irq, void *arg) +{ + struct twl4030_bci *bci = arg; + + dev_dbg(bci->dev, "CHG_PRES irq\n"); + power_supply_changed(&bci->ac); + power_supply_changed(&bci->usb); + + return IRQ_HANDLED; +} + +/* + * TWL4030 BCI monitoring events + */ +static irqreturn_t twl4030_bci_interrupt(int irq, void *arg) +{ + struct twl4030_bci *bci = arg; + u8 irqs1, irqs2; + int ret; + + ret = twl_i2c_read_u8(TWL4030_MODULE_INTERRUPTS, &irqs1, + TWL4030_INTERRUPTS_BCIISR1A); + if (ret < 0) + return IRQ_HANDLED; + + ret = twl_i2c_read_u8(TWL4030_MODULE_INTERRUPTS, &irqs2, + TWL4030_INTERRUPTS_BCIISR2A); + if (ret < 0) + return IRQ_HANDLED; + + dev_dbg(bci->dev, "BCI irq %02x %02x\n", irqs2, irqs1); + + if (irqs1 & (TWL4030_ICHGLOW | TWL4030_ICHGEOC)) { + /* charger state change, inform the core */ + power_supply_changed(&bci->ac); + power_supply_changed(&bci->usb); + } + + /* various monitoring events, for now we just log them here */ + if (irqs1 & (TWL4030_TBATOR2 | TWL4030_TBATOR1)) + dev_warn(bci->dev, "battery temperature out of range\n"); + + if (irqs1 & TWL4030_BATSTS) + dev_crit(bci->dev, "battery disconnected\n"); + + if (irqs2 & TWL4030_VBATOV) + dev_crit(bci->dev, "VBAT overvoltage\n"); + + if (irqs2 & TWL4030_VBUSOV) + dev_crit(bci->dev, "VBUS overvoltage\n"); + + if (irqs2 & TWL4030_ACCHGOV) + dev_crit(bci->dev, "Ac charger overvoltage\n"); + + return IRQ_HANDLED; +} + +static int twl4030_bci_usb_ncb(struct notifier_block *nb, unsigned long val, + void *priv) +{ + struct twl4030_bci *bci = container_of(nb, struct twl4030_bci, otg_nb); + + dev_dbg(bci->dev, "OTG notify %lu\n", val); + + switch (val) { + case USB_EVENT_VBUS: + case USB_EVENT_CHARGER: + twl4030_charger_enable_usb(bci, true); + break; + case USB_EVENT_NONE: + twl4030_charger_enable_usb(bci, false); + break; + } + + return NOTIFY_OK; +} + +/* + * TI provided formulas: + * CGAIN == 0: ICHG = (BCIICHG * 1.7) / (2^10 - 1) - 0.85 + * CGAIN == 1: ICHG = (BCIICHG * 3.4) / (2^10 - 1) - 1.7 + * Here we use integer approximation of: + * CGAIN == 0: val * 1.6618 - 0.85 + * CGAIN == 1: (val * 1.6618 - 0.85) * 2 + */ +static int twl4030_charger_get_current(void) +{ + int curr; + int ret; + u8 bcictl1; + + curr = twl4030bci_read_adc_val(TWL4030_BCIICHG); + if (curr < 0) + return curr; + + ret = twl4030_bci_read(TWL4030_BCICTL1, &bcictl1); + if (ret) + return ret; + + ret = (curr * 16618 - 850 * 10000) / 10; + if (bcictl1 & TWL4030_CGAIN) + ret *= 2; + + return ret; +} + +/* + * Returns the main charge FSM state + * Or < 0 on failure. + */ +static int twl4030bci_state(struct twl4030_bci *bci) +{ + int ret; + u8 state; + + ret = twl4030_bci_read(TWL4030_BCIMSTATEC, &state); + if (ret) { + pr_err("twl4030_bci: error reading BCIMSTATEC\n"); + return ret; + } + + dev_dbg(bci->dev, "state: %02x\n", state); + + return state; +} + +static int twl4030_bci_state_to_status(int state) +{ + state &= TWL4030_MSTATEC_MASK; + if (TWL4030_MSTATEC_QUICK1 <= state && state <= TWL4030_MSTATEC_QUICK7) + return POWER_SUPPLY_STATUS_CHARGING; + else if (TWL4030_MSTATEC_COMPLETE1 <= state && + state <= TWL4030_MSTATEC_COMPLETE4) + return POWER_SUPPLY_STATUS_FULL; + else + return POWER_SUPPLY_STATUS_NOT_CHARGING; +} + +static int twl4030_bci_get_property(struct power_supply *psy, + enum power_supply_property psp, + union power_supply_propval *val) +{ + struct twl4030_bci *bci = dev_get_drvdata(psy->dev->parent); + int is_charging; + int state; + int ret; + + state = twl4030bci_state(bci); + if (state < 0) + return state; + + if (psy->type == POWER_SUPPLY_TYPE_USB) + is_charging = state & TWL4030_MSTATEC_USB; + else + is_charging = state & TWL4030_MSTATEC_AC; + + switch (psp) { + case POWER_SUPPLY_PROP_STATUS: + if (is_charging) + val->intval = twl4030_bci_state_to_status(state); + else + val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING; + break; + case POWER_SUPPLY_PROP_VOLTAGE_NOW: + /* charging must be active for meaningful result */ + if (!is_charging) + return -ENODATA; + if (psy->type == POWER_SUPPLY_TYPE_USB) { + ret = twl4030bci_read_adc_val(TWL4030_BCIVBUS); + if (ret < 0) + return ret; + /* BCIVBUS uses ADCIN8, 7/1023 V/step */ + val->intval = ret * 6843; + } else { + ret = twl4030bci_read_adc_val(TWL4030_BCIVAC); + if (ret < 0) + return ret; + /* BCIVAC uses ADCIN11, 10/1023 V/step */ + val->intval = ret * 9775; + } + break; + case POWER_SUPPLY_PROP_CURRENT_NOW: + if (!is_charging) + return -ENODATA; + /* current measurement is shared between AC and USB */ + ret = twl4030_charger_get_current(); + if (ret < 0) + return ret; + val->intval = ret; + break; + case POWER_SUPPLY_PROP_ONLINE: + val->intval = is_charging && + twl4030_bci_state_to_status(state) != + POWER_SUPPLY_STATUS_NOT_CHARGING; + break; + default: + return -EINVAL; + } + + return 0; +} + +static enum power_supply_property twl4030_charger_props[] = { + POWER_SUPPLY_PROP_STATUS, + POWER_SUPPLY_PROP_ONLINE, + POWER_SUPPLY_PROP_VOLTAGE_NOW, + POWER_SUPPLY_PROP_CURRENT_NOW, +}; + +static int __init twl4030_bci_probe(struct platform_device *pdev) +{ + struct twl4030_bci *bci; + int ret; + int reg; + + bci = kzalloc(sizeof(*bci), GFP_KERNEL); + if (bci == NULL) + return -ENOMEM; + + bci->dev = &pdev->dev; + bci->irq_chg = platform_get_irq(pdev, 0); + bci->irq_bci = platform_get_irq(pdev, 1); + + platform_set_drvdata(pdev, bci); + + bci->ac.name = "twl4030_ac"; + bci->ac.type = POWER_SUPPLY_TYPE_MAINS; + bci->ac.properties = twl4030_charger_props; + bci->ac.num_properties = ARRAY_SIZE(twl4030_charger_props); + bci->ac.get_property = twl4030_bci_get_property; + + ret = power_supply_register(&pdev->dev, &bci->ac); + if (ret) { + dev_err(&pdev->dev, "failed to register ac: %d\n", ret); + goto fail_register_ac; + } + + bci->usb.name = "twl4030_usb"; + bci->usb.type = POWER_SUPPLY_TYPE_USB; + bci->usb.properties = twl4030_charger_props; + bci->usb.num_properties = ARRAY_SIZE(twl4030_charger_props); + bci->usb.get_property = twl4030_bci_get_property; + + ret = power_supply_register(&pdev->dev, &bci->usb); + if (ret) { + dev_err(&pdev->dev, "failed to register usb: %d\n", ret); + goto fail_register_usb; + } + + ret = request_threaded_irq(bci->irq_chg, NULL, + twl4030_charger_interrupt, 0, pdev->name, bci); + if (ret < 0) { + dev_err(&pdev->dev, "could not request irq %d, status %d\n", + bci->irq_chg, ret); + goto fail_chg_irq; + } + + ret = request_threaded_irq(bci->irq_bci, NULL, + twl4030_bci_interrupt, 0, pdev->name, bci); + if (ret < 0) { + dev_err(&pdev->dev, "could not request irq %d, status %d\n", + bci->irq_bci, ret); + goto fail_bci_irq; + } + + bci->transceiver = otg_get_transceiver(); + if (bci->transceiver != NULL) { + bci->otg_nb.notifier_call = twl4030_bci_usb_ncb; + otg_register_notifier(bci->transceiver, &bci->otg_nb); + } + + /* Enable interrupts now. */ + reg = ~(TWL4030_ICHGLOW | TWL4030_ICHGEOC | TWL4030_TBATOR2 | + TWL4030_TBATOR1 | TWL4030_BATSTS); + ret = twl_i2c_write_u8(TWL4030_MODULE_INTERRUPTS, reg, + TWL4030_INTERRUPTS_BCIIMR1A); + if (ret < 0) { + dev_err(&pdev->dev, "failed to unmask interrupts: %d\n", ret); + goto fail_unmask_interrupts; + } + + reg = ~(TWL4030_VBATOV | TWL4030_VBUSOV | TWL4030_ACCHGOV); + ret = twl_i2c_write_u8(TWL4030_MODULE_INTERRUPTS, reg, + TWL4030_INTERRUPTS_BCIIMR2A); + if (ret < 0) + dev_warn(&pdev->dev, "failed to unmask interrupts: %d\n", ret); + + twl4030_charger_enable_ac(true); + twl4030_charger_enable_usb(bci, true); + + return 0; + +fail_unmask_interrupts: + if (bci->transceiver != NULL) { + otg_unregister_notifier(bci->transceiver, &bci->otg_nb); + otg_put_transceiver(bci->transceiver); + } + free_irq(bci->irq_bci, bci); +fail_bci_irq: + free_irq(bci->irq_chg, bci); +fail_chg_irq: + power_supply_unregister(&bci->usb); +fail_register_usb: + power_supply_unregister(&bci->ac); +fail_register_ac: + platform_set_drvdata(pdev, NULL); + kfree(bci); + + return ret; +} + +static int __exit twl4030_bci_remove(struct platform_device *pdev) +{ + struct twl4030_bci *bci = platform_get_drvdata(pdev); + + twl4030_charger_enable_ac(false); + twl4030_charger_enable_usb(bci, false); + + /* mask interrupts */ + twl_i2c_write_u8(TWL4030_MODULE_INTERRUPTS, 0xff, + TWL4030_INTERRUPTS_BCIIMR1A); + twl_i2c_write_u8(TWL4030_MODULE_INTERRUPTS, 0xff, + TWL4030_INTERRUPTS_BCIIMR2A); + + if (bci->transceiver != NULL) { + otg_unregister_notifier(bci->transceiver, &bci->otg_nb); + otg_put_transceiver(bci->transceiver); + } + free_irq(bci->irq_bci, bci); + free_irq(bci->irq_chg, bci); + power_supply_unregister(&bci->usb); + power_supply_unregister(&bci->ac); + platform_set_drvdata(pdev, NULL); + kfree(bci); + + return 0; +} + +static struct platform_driver twl4030_bci_driver = { + .driver = { + .name = "twl4030_bci", + .owner = THIS_MODULE, + }, + .remove = __exit_p(twl4030_bci_remove), +}; + +static int __init twl4030_bci_init(void) +{ + return platform_driver_probe(&twl4030_bci_driver, twl4030_bci_probe); +} +module_init(twl4030_bci_init); + +static void __exit twl4030_bci_exit(void) +{ + platform_driver_unregister(&twl4030_bci_driver); +} +module_exit(twl4030_bci_exit); + +MODULE_AUTHOR("Gražydas Ignotas"); +MODULE_DESCRIPTION("TWL4030 Battery Charger Interface driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:twl4030_bci"); |
