lkml.org 
[lkml]   [2009]   [Nov]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH] power_supply: Add driver for TWL4030/TPS65950 BCI charger
    Date
    TWL4030/TPS65950 is a multi-function device with integrated charger,
    which allows charging from AC or USB. This driver enables the
    charger and provides several monitoring functions.

    Signed-off-by: Grazvydas Ignotas <notasas@gmail.com>
    ---
    For this driver to work, TWL4030-core needs to be patched to use
    correct macros so that it registers twl4030_bci platform_device.
    I'll send patches for this later.

    drivers/power/Kconfig | 7 +
    drivers/power/Makefile | 1 +
    drivers/power/twl4030_charger.c | 499 +++++++++++++++++++++++++++++++++++++++
    3 files changed, 507 insertions(+), 0 deletions(-)
    create mode 100644 drivers/power/twl4030_charger.c

    diff --git a/drivers/power/Kconfig b/drivers/power/Kconfig
    index cea6cef..95d7e60 100644
    --- a/drivers/power/Kconfig
    +++ b/drivers/power/Kconfig
    @@ -110,4 +110,11 @@ config CHARGER_PCF50633
    help
    Say Y to include support for NXP PCF50633 Main Battery Charger.

    +config CHARGER_TWL4030
    + tristate "OMAP TWL4030 BCI charger driver"
    + depends on TWL4030_CORE
    + default y
    + help
    + Say Y here to enable support for TWL4030 Battery Charge Interface.
    +
    endif # POWER_SUPPLY
    diff --git a/drivers/power/Makefile b/drivers/power/Makefile
    index b96f29d..9cea9b5 100644
    --- a/drivers/power/Makefile
    +++ b/drivers/power/Makefile
    @@ -29,3 +29,4 @@ obj-$(CONFIG_BATTERY_BQ27x00) += bq27x00_battery.o
    obj-$(CONFIG_BATTERY_DA9030) += da9030_battery.o
    obj-$(CONFIG_BATTERY_MAX17040) += max17040_battery.o
    obj-$(CONFIG_CHARGER_PCF50633) += pcf50633-charger.o
    +obj-$(CONFIG_CHARGER_TWL4030) += twl4030_charger.o
    diff --git a/drivers/power/twl4030_charger.c b/drivers/power/twl4030_charger.c
    new file mode 100644
    index 0000000..604dd56
    --- /dev/null
    +++ b/drivers/power/twl4030_charger.c
    @@ -0,0 +1,499 @@
    +/*
    + * TWL4030/TPS65950 BCI (Battery Charger Interface) driver
    + *
    + * Copyright (C) 2009 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/platform_device.h>
    +#include <linux/interrupt.h>
    +#include <linux/i2c/twl4030.h>
    +#include <linux/power_supply.h>
    +
    +#define REG_BCIMSTATEC 0x02
    +#define REG_BCIICHG 0x08
    +#define REG_BCIVAC 0x0a
    +#define REG_BCIVBUS 0x0c
    +#define REG_BCIMFSTS4 0x10
    +#define REG_BCICTL1 0x23
    +
    +#define REG_BOOT_BCI 0x07
    +#define REG_STS_HW_CONDITIONS 0x0f
    +
    +#define BCIAUTOWEN 0x20
    +#define CONFIG_DONE 0x10
    +#define CVENAC 0x04
    +#define BCIAUTOUSB 0x02
    +#define BCIAUTOAC 0x01
    +#define BCIMSTAT_MASK 0x3F
    +#define STS_VBUS 0x80
    +#define STS_CHG 0x02
    +#define STS_USB_ID 0x04
    +#define CGAIN 0x20
    +#define USBFASTMCHG 0x04
    +
    +#define STATEC_USB 0x10
    +#define STATEC_AC 0x20
    +#define STATEC_STATUS_MASK 0x0f
    +#define STATEC_QUICK1 0x02
    +#define STATEC_QUICK7 0x07
    +#define STATEC_COMPLETE1 0x0b
    +#define STATEC_COMPLETE4 0x0e
    +
    +#define BCI_DELAY 100
    +
    +struct twl4030_bci_device_info {
    + struct power_supply ac;
    + struct power_supply usb;
    + struct delayed_work bat_work;
    + bool started;
    +};
    +
    +/*
    + * 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 = twl4030_i2c_read_u8(mod_no, &val, reg);
    + if (ret)
    + return ret;
    +
    + val &= ~clear;
    + val |= set;
    +
    + return twl4030_i2c_write_u8(mod_no, val, reg);
    +}
    +
    +static int twl4030bci_read_adc_val(u8 reg)
    +{
    + int ret, temp;
    + u8 val;
    +
    + /* read MSB */
    + ret = twl4030_i2c_read_u8(TWL4030_MODULE_MAIN_CHARGE, &val, reg + 1);
    + if (ret)
    + return ret;
    +
    + temp = (int)(val & 0x03) << 8;
    +
    + /* read LSB */
    + ret = twl4030_i2c_read_u8(TWL4030_MODULE_MAIN_CHARGE, &val, reg);
    + if (ret)
    + return ret;
    +
    + return temp | val;
    +}
    +
    +static void twl4030bci_power_work(struct work_struct *work)
    +{
    + struct twl4030_bci_device_info *di = container_of(work,
    + struct twl4030_bci_device_info, bat_work.work);
    +
    + power_supply_changed(&di->ac);
    + power_supply_changed(&di->usb);
    +}
    +
    +/*
    + * Attend to TWL4030 CHG_PRES (AC charger presence) events
    + */
    +static irqreturn_t twl4030_charger_interrupt(int irq, void *_di)
    +{
    + struct twl4030_bci_device_info *di = _di;
    +
    +#ifdef CONFIG_LOCKDEP
    + /* WORKAROUND for lockdep forcing IRQF_DISABLED on us, which
    + * we don't want and can't tolerate. Although it might be
    + * friendlier not to borrow this thread context...
    + */
    + local_irq_enable();
    +#endif
    +
    + schedule_delayed_work(&di->bat_work, msecs_to_jiffies(BCI_DELAY));
    +
    + return IRQ_HANDLED;
    +}
    +
    +/*
    + * Enable/Disable AC Charge funtionality.
    + */
    +static int twl4030_charger_enable_ac(bool enable)
    +{
    + int ret;
    +
    + if (enable) {
    + /* forcing the field BCIAUTOAC (BOOT_BCI[0) to 1 */
    + ret = twl4030_clear_set(TWL4030_MODULE_PM_MASTER, 0,
    + CONFIG_DONE | BCIAUTOWEN | BCIAUTOAC,
    + REG_BOOT_BCI);
    + } else {
    + /* forcing the field BCIAUTOAC (BOOT_BCI[0) to 0*/
    + ret = twl4030_clear_set(TWL4030_MODULE_PM_MASTER, BCIAUTOAC,
    + CONFIG_DONE | BCIAUTOWEN,
    + REG_BOOT_BCI);
    + }
    +
    + return ret;
    +}
    +
    +/*
    + * Check if VBUS power is present
    + */
    +static int twl4030_charger_check_vbus(void)
    +{
    + int ret;
    + u8 hwsts;
    +
    + ret = twl4030_i2c_read_u8(TWL4030_MODULE_PM_MASTER, &hwsts,
    + REG_STS_HW_CONDITIONS);
    + if (ret) {
    + pr_err("twl4030_bci: error reading STS_HW_CONDITIONS\n");
    + return ret;
    + }
    +
    + pr_debug("check_vbus: HW_CONDITIONS %02x\n", hwsts);
    +
    + /* in case we also have STS_USB_ID, VBUS is driven by TWL itself */
    + if ((hwsts & STS_VBUS) && !(hwsts & STS_USB_ID))
    + return 1;
    +
    + return 0;
    +}
    +
    +/*
    + * Enable/Disable USB Charge funtionality.
    + */
    +static int twl4030_charger_enable_usb(bool enable)
    +{
    + int ret;
    +
    + if (enable) {
    + /* Check for USB charger conneted */
    + ret = twl4030_charger_check_vbus();
    + if (ret < 0)
    + return ret;
    +
    + if (!ret)
    + return -ENXIO;
    +
    + /* forcing the field BCIAUTOUSB (BOOT_BCI[1]) to 1 */
    + ret = twl4030_clear_set(TWL4030_MODULE_PM_MASTER, 0,
    + CONFIG_DONE | BCIAUTOWEN | BCIAUTOUSB,
    + REG_BOOT_BCI);
    + if (ret)
    + return ret;
    +
    + /* forcing USBFASTMCHG(BCIMFSTS4[2]) to 1 */
    + ret = twl4030_clear_set(TWL4030_MODULE_MAIN_CHARGE, 0,
    + USBFASTMCHG, REG_BCIMFSTS4);
    + } else {
    + ret = twl4030_clear_set(TWL4030_MODULE_PM_MASTER, BCIAUTOUSB,
    + CONFIG_DONE | BCIAUTOWEN, REG_BOOT_BCI);
    + }
    +
    + return ret;
    +}
    +
    +/*
    + * Return voltage (valid while charging only)
    + * 10 bit ADC (0...0x3ff) scales to 0...6V
    + */
    +static int twl4030_get_voltage(int reg)
    +{
    + int ret = twl4030bci_read_adc_val(reg);
    + if (ret < 0)
    + return ret;
    +
    + return 6000 * ret / 1023;
    +}
    +
    +/*
    + * 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(REG_BCIICHG);
    + if (curr < 0)
    + return curr;
    +
    + ret = twl4030_i2c_read_u8(TWL4030_MODULE_MAIN_CHARGE, &bcictl1,
    + REG_BCICTL1);
    + if (ret)
    + return ret;
    +
    + ret = (curr * 16618 - 850 * 10000) / 10000;
    + if (bcictl1 & CGAIN)
    + ret *= 2;
    +
    + return ret;
    +}
    +
    +/*
    + * Returns the main charge FSM state
    + * Or < 0 on failure.
    + */
    +static int twl4030bci_state(void)
    +{
    + int ret;
    + u8 state;
    +
    + ret = twl4030_i2c_read_u8(TWL4030_MODULE_MAIN_CHARGE,
    + &state, REG_BCIMSTATEC);
    + if (ret) {
    + pr_err("twl4030_bci: error reading BCIMSTATEC\n");
    + return ret;
    + }
    +
    + pr_debug("state: %02x\n", state);
    +
    + return state & BCIMSTAT_MASK;
    +}
    +
    +static int twl4030_bci_state_to_status(int state)
    +{
    + state &= STATEC_STATUS_MASK;
    + if (STATEC_QUICK1 <= state && state <= STATEC_QUICK7)
    + return POWER_SUPPLY_STATUS_CHARGING;
    + else if (STATEC_COMPLETE1 <= state && state <= STATEC_COMPLETE4)
    + return POWER_SUPPLY_STATUS_FULL;
    + else
    + return POWER_SUPPLY_STATUS_NOT_CHARGING;
    +}
    +
    +static int twl4030_charger_get_property(struct power_supply *psy,
    + enum power_supply_property psp,
    + union power_supply_propval *val)
    +{
    + int is_charging;
    + int voltage_reg;
    + int state;
    + int ret;
    +
    + state = twl4030bci_state();
    + if (state < 0)
    + return state;
    +
    + if (psy->type == POWER_SUPPLY_TYPE_USB) {
    + is_charging = state & STATEC_USB;
    + voltage_reg = REG_BCIVBUS;
    + } else {
    + is_charging = state & STATEC_AC;
    + voltage_reg = REG_BCIVAC;
    + }
    +
    + 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) {
    + val->intval = 0;
    + break;
    + }
    + ret = twl4030_get_voltage(voltage_reg);
    + if (ret < 0)
    + return ret;
    + val->intval = ret;
    + break;
    + case POWER_SUPPLY_PROP_CURRENT_NOW:
    + if (!is_charging) {
    + val->intval = 0;
    + break;
    + }
    + /* 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 struct twl4030_bci_device_info twl4030_bci = {
    + .ac = {
    + .name = "twl4030_ac",
    + .type = POWER_SUPPLY_TYPE_MAINS,
    + .properties = twl4030_charger_props,
    + .num_properties = ARRAY_SIZE(twl4030_charger_props),
    + .get_property = twl4030_charger_get_property,
    + },
    + .usb = {
    + .name = "twl4030_usb",
    + .type = POWER_SUPPLY_TYPE_USB,
    + .properties = twl4030_charger_props,
    + .num_properties = ARRAY_SIZE(twl4030_charger_props),
    + .get_property = twl4030_charger_get_property,
    + },
    +};
    +
    +/*
    + * called by TWL4030 USB transceiver driver on USB_PRES interrupt.
    + */
    +int twl4030charger_usb_en(int enable)
    +{
    + if (twl4030_bci.started)
    + schedule_delayed_work(&twl4030_bci.bat_work,
    + msecs_to_jiffies(BCI_DELAY));
    +
    + return twl4030_charger_enable_usb(enable);
    +}
    +
    +static int __devinit twl4030_bci_probe(struct platform_device *pdev)
    +{
    + int irq;
    + int ret;
    +
    + twl4030_charger_enable_ac(true);
    + twl4030_charger_enable_usb(true);
    +
    + irq = platform_get_irq(pdev, 0);
    +
    + /* CHG_PRES irq */
    + ret = request_irq(irq, twl4030_charger_interrupt,
    + 0, pdev->name, &twl4030_bci);
    + if (ret) {
    + dev_err(&pdev->dev, "could not request irq %d, status %d\n",
    + irq, ret);
    + goto fail_chg_irq;
    + }
    +
    + ret = power_supply_register(&pdev->dev, &twl4030_bci.ac);
    + if (ret) {
    + dev_err(&pdev->dev, "failed to register ac: %d\n", ret);
    + goto fail_register_ac;
    + }
    +
    + ret = power_supply_register(&pdev->dev, &twl4030_bci.usb);
    + if (ret) {
    + dev_err(&pdev->dev, "failed to register usb: %d\n", ret);
    + goto fail_register_usb;
    + }
    +
    + platform_set_drvdata(pdev, &twl4030_bci);
    +
    + INIT_DELAYED_WORK_DEFERRABLE(&twl4030_bci.bat_work,
    + twl4030bci_power_work);
    + schedule_delayed_work(&twl4030_bci.bat_work,
    + msecs_to_jiffies(BCI_DELAY));
    + twl4030_bci.started = true;
    +
    + return 0;
    +
    +fail_register_usb:
    + power_supply_unregister(&twl4030_bci.ac);
    +fail_register_ac:
    + free_irq(irq, &twl4030_bci);
    +fail_chg_irq:
    + twl4030_charger_enable_ac(false);
    + twl4030_charger_enable_usb(false);
    +
    + return ret;
    +}
    +
    +static int __devexit twl4030_bci_remove(struct platform_device *pdev)
    +{
    + struct twl4030_bci_device_info *di = platform_get_drvdata(pdev);
    + int irq = platform_get_irq(pdev, 0);
    +
    + di->started = false;
    + twl4030_charger_enable_ac(false);
    + twl4030_charger_enable_usb(false);
    +
    + free_irq(irq, di);
    +
    + flush_scheduled_work();
    + power_supply_unregister(&di->ac);
    + power_supply_unregister(&di->usb);
    + platform_set_drvdata(pdev, NULL);
    +
    + return 0;
    +}
    +
    +#ifdef CONFIG_PM
    +static int twl4030_bci_suspend(struct platform_device *pdev,
    + pm_message_t state)
    +{
    + /* flush all pending status updates */
    + flush_scheduled_work();
    + return 0;
    +}
    +
    +static int twl4030_bci_resume(struct platform_device *pdev)
    +{
    + struct twl4030_bci_device_info *di = platform_get_drvdata(pdev);
    +
    + /* things may have changed while we were away */
    + schedule_delayed_work(&di->bat_work, msecs_to_jiffies(BCI_DELAY));
    + return 0;
    +}
    +#else
    +#define twl4030_bci_suspend NULL
    +#define twl4030_bci_resume NULL
    +#endif /* CONFIG_PM */
    +
    +static struct platform_driver twl4030_bci_driver = {
    + .probe = twl4030_bci_probe,
    + .remove = __devexit_p(twl4030_bci_remove),
    + .suspend = twl4030_bci_suspend,
    + .resume = twl4030_bci_resume,
    + .driver = {
    + .name = "twl4030_bci",
    + .owner = THIS_MODULE,
    + },
    +};
    +
    +static int __init twl4030_bci_init(void)
    +{
    + return platform_driver_register(&twl4030_bci_driver);
    +}
    +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("Gražvydas Ignotas");
    +MODULE_DESCRIPTION("TWL4030 Battery Charger Interface driver");
    +MODULE_LICENSE("GPL");
    +MODULE_ALIAS("platform:twl4030_bci");
    --
    1.6.3.3
    --
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2009-11-27 15:47    [W:0.058 / U:118.648 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site