Commit 2e727f17 authored by Grazvydas Ignotas's avatar Grazvydas Ignotas Committed by Anton Vorontsov
Browse files

power_supply: Add driver for TWL4030/TPS65950 BCI charger 



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.

Tested on OMAP3 Pandora board.

Signed-off-by: default avatarGrazvydas Ignotas <notasas@gmail.com>
Acked-by: default avatarFelipe Balbi <balbi@ti.com>
Signed-off-by: default avatarAnton Vorontsov <cbouatmailru@gmail.com>
parent d3ab61ec

drivers/power/Kconfig

+6 −0
Original line number Diff line number Diff line
@@ -179,4 +179,10 @@ config CHARGER_ISP1704 
	  Say Y to enable support for USB Charger Detection with

	  ISP1707/ISP1704 USB transceivers.



config CHARGER_TWL4030

	tristate "OMAP TWL4030 BCI charger driver"

	depends on TWL4030_CORE

	help

	  Say Y here to enable support for TWL4030 Battery Charge Interface.



endif # POWER_SUPPLY

drivers/power/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -39,3 +39,4 @@ obj-$(CONFIG_CHARGER_PCF50633) += pcf50633-charger.o 
obj-$(CONFIG_BATTERY_JZ4740)	+= jz4740-battery.o

obj-$(CONFIG_BATTERY_INTEL_MID)	+= intel_mid_battery.o

obj-$(CONFIG_CHARGER_ISP1704)	+= isp1704_charger.o

obj-$(CONFIG_CHARGER_TWL4030)	+= twl4030_charger.o

drivers/power/twl4030_charger.c

0 → 100644
+565 −0
Original line number Diff line number Diff line 
/*

 * 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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