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-rw-r--r--drivers/power/twl4030_charger.c565
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");
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