extcon-max8997.c

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/*
 * extcon-max8997.c - MAX8997 extcon driver to support MAX8997 MUIC
 *
 *  Copyright (C) 2012 Samsung Electrnoics
 *  Donggeun Kim <[email protected]>
 *
 * 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.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/kobject.h>
#include <linux/mfd/max8997.h>
#include <linux/mfd/max8997-private.h>
#include <linux/extcon.h>
#include <linux/irqdomain.h>

#define DEV_NAME            "max8997-muic"

/* MAX8997-MUIC STATUS1 register */
#define STATUS1_ADC_SHIFT       0
#define STATUS1_ADCLOW_SHIFT        5
#define STATUS1_ADCERR_SHIFT        6
#define STATUS1_ADC_MASK        (0x1f << STATUS1_ADC_SHIFT)
#define STATUS1_ADCLOW_MASK     (0x1 << STATUS1_ADCLOW_SHIFT)
#define STATUS1_ADCERR_MASK     (0x1 << STATUS1_ADCERR_SHIFT)

/* MAX8997-MUIC STATUS2 register */
#define STATUS2_CHGTYP_SHIFT        0
#define STATUS2_CHGDETRUN_SHIFT     3
#define STATUS2_DCDTMR_SHIFT        4
#define STATUS2_DBCHG_SHIFT     5
#define STATUS2_VBVOLT_SHIFT        6
#define STATUS2_CHGTYP_MASK     (0x7 << STATUS2_CHGTYP_SHIFT)
#define STATUS2_CHGDETRUN_MASK      (0x1 << STATUS2_CHGDETRUN_SHIFT)
#define STATUS2_DCDTMR_MASK     (0x1 << STATUS2_DCDTMR_SHIFT)
#define STATUS2_DBCHG_MASK      (0x1 << STATUS2_DBCHG_SHIFT)
#define STATUS2_VBVOLT_MASK     (0x1 << STATUS2_VBVOLT_SHIFT)

/* MAX8997-MUIC STATUS3 register */
#define STATUS3_OVP_SHIFT       2
#define STATUS3_OVP_MASK        (0x1 << STATUS3_OVP_SHIFT)

/* MAX8997-MUIC CONTROL1 register */
#define COMN1SW_SHIFT           0
#define COMP2SW_SHIFT           3
#define COMN1SW_MASK            (0x7 << COMN1SW_SHIFT)
#define COMP2SW_MASK            (0x7 << COMP2SW_SHIFT)
#define SW_MASK             (COMP2SW_MASK | COMN1SW_MASK)

#define MAX8997_SW_USB      ((1 << COMP2SW_SHIFT) | (1 << COMN1SW_SHIFT))
#define MAX8997_SW_AUDIO    ((2 << COMP2SW_SHIFT) | (2 << COMN1SW_SHIFT))
#define MAX8997_SW_UART     ((3 << COMP2SW_SHIFT) | (3 << COMN1SW_SHIFT))
#define MAX8997_SW_OPEN     ((0 << COMP2SW_SHIFT) | (0 << COMN1SW_SHIFT))

#define MAX8997_ADC_GROUND      0x00
#define MAX8997_ADC_MHL         0x01
#define MAX8997_ADC_JIG_USB_1       0x18
#define MAX8997_ADC_JIG_USB_2       0x19
#define MAX8997_ADC_DESKDOCK        0x1a
#define MAX8997_ADC_JIG_UART        0x1c
#define MAX8997_ADC_CARDOCK     0x1d
#define MAX8997_ADC_OPEN        0x1f

struct max8997_muic_irq {
    unsigned int irq;
    const char *name;
    unsigned int virq;
};

static struct max8997_muic_irq muic_irqs[] = {
    { MAX8997_MUICIRQ_ADCError, "muic-ADC_error" },
    { MAX8997_MUICIRQ_ADCLow, "muic-ADC_low" },
    { MAX8997_MUICIRQ_ADC, "muic-ADC" },
    { MAX8997_MUICIRQ_VBVolt, "muic-VB_voltage" },
    { MAX8997_MUICIRQ_DBChg, "muic-DB_charger" },
    { MAX8997_MUICIRQ_DCDTmr, "muic-DCD_timer" },
    { MAX8997_MUICIRQ_ChgDetRun, "muic-CDR_status" },
    { MAX8997_MUICIRQ_ChgTyp, "muic-charger_type" },
    { MAX8997_MUICIRQ_OVP, "muic-over_voltage" },
};

struct max8997_muic_info {
    struct device *dev;
    struct i2c_client *muic;
    struct max8997_muic_platform_data *muic_pdata;

    int irq;
    struct work_struct irq_work;

    enum max8997_muic_charger_type pre_charger_type;
    int pre_adc;

    struct mutex mutex;

    struct extcon_dev   *edev;
};

const char *max8997_extcon_cable[] = {
    [0] = "USB",
    [1] = "USB-Host",
    [2] = "TA",
    [3] = "Fast-charger",
    [4] = "Slow-charger",
    [5] = "Charge-downstream",
    [6] = "MHL",
    [7] = "Dock-desk",
    [8] = "Dock-card",
    [9] = "JIG",

    NULL,
};

static int max8997_muic_handle_usb(struct max8997_muic_info *info,
            enum max8997_muic_usb_type usb_type, bool attached)
{
    int ret = 0;

    if (usb_type == MAX8997_USB_HOST) {
        /* switch to USB */
        ret = max8997_update_reg(info->muic, MAX8997_MUIC_REG_CONTROL1,
                attached ? MAX8997_SW_USB : MAX8997_SW_OPEN,
                SW_MASK);
        if (ret) {
            dev_err(info->dev, "failed to update muic register\n");
            goto out;
        }
    }

    switch (usb_type) {
    case MAX8997_USB_HOST:
        extcon_set_cable_state(info->edev, "USB-Host", attached);
        break;
    case MAX8997_USB_DEVICE:
        extcon_set_cable_state(info->edev, "USB", attached);
        break;
    default:
        ret = -EINVAL;
        break;
    }

out:
    return ret;
}

static int max8997_muic_handle_dock(struct max8997_muic_info *info,
            int adc, bool attached)
{
    int ret = 0;

    /* switch to AUDIO */
    ret = max8997_update_reg(info->muic, MAX8997_MUIC_REG_CONTROL1,
                attached ? MAX8997_SW_AUDIO : MAX8997_SW_OPEN,
                SW_MASK);
    if (ret) {
        dev_err(info->dev, "failed to update muic register\n");
        goto out;
    }

    switch (adc) {
    case MAX8997_ADC_DESKDOCK:
        extcon_set_cable_state(info->edev, "Dock-desk", attached);
        break;
    case MAX8997_ADC_CARDOCK:
        extcon_set_cable_state(info->edev, "Dock-card", attached);
        break;
    default:
        ret = -EINVAL;
        break;
    }
out:
    return ret;
}

static int max8997_muic_handle_jig_uart(struct max8997_muic_info *info,
            bool attached)
{
    int ret = 0;

    /* switch to UART */
    ret = max8997_update_reg(info->muic, MAX8997_MUIC_REG_CONTROL1,
                attached ? MAX8997_SW_UART : MAX8997_SW_OPEN,
                SW_MASK);
    if (ret) {
        dev_err(info->dev, "failed to update muic register\n");
        goto out;
    }

    extcon_set_cable_state(info->edev, "JIG", attached);
out:
    return ret;
}

static int max8997_muic_handle_adc_detach(struct max8997_muic_info *info)
{
    int ret = 0;

    switch (info->pre_adc) {
    case MAX8997_ADC_GROUND:
        ret = max8997_muic_handle_usb(info, MAX8997_USB_HOST, false);
        break;
    case MAX8997_ADC_MHL:
        extcon_set_cable_state(info->edev, "MHL", false);
        break;
    case MAX8997_ADC_JIG_USB_1:
    case MAX8997_ADC_JIG_USB_2:
        ret = max8997_muic_handle_usb(info, MAX8997_USB_DEVICE, false);
        break;
    case MAX8997_ADC_DESKDOCK:
    case MAX8997_ADC_CARDOCK:
        ret = max8997_muic_handle_dock(info, info->pre_adc, false);
        break;
    case MAX8997_ADC_JIG_UART:
        ret = max8997_muic_handle_jig_uart(info, false);
        break;
    default:
        break;
    }

    return ret;
}

static int max8997_muic_handle_adc(struct max8997_muic_info *info, int adc)
{
    int ret = 0;

    switch (adc) {
    case MAX8997_ADC_GROUND:
        ret = max8997_muic_handle_usb(info, MAX8997_USB_HOST, true);
        break;
    case MAX8997_ADC_MHL:
        extcon_set_cable_state(info->edev, "MHL", true);
        break;
    case MAX8997_ADC_JIG_USB_1:
    case MAX8997_ADC_JIG_USB_2:
        ret = max8997_muic_handle_usb(info, MAX8997_USB_DEVICE, true);
        break;
    case MAX8997_ADC_DESKDOCK:
    case MAX8997_ADC_CARDOCK:
        ret = max8997_muic_handle_dock(info, adc, true);
        break;
    case MAX8997_ADC_JIG_UART:
        ret = max8997_muic_handle_jig_uart(info, true);
        break;
    case MAX8997_ADC_OPEN:
        ret = max8997_muic_handle_adc_detach(info);
        break;
    default:
        ret = -EINVAL;
        goto out;
    }

    info->pre_adc = adc;
out:
    return ret;
}

static int max8997_muic_handle_charger_type_detach(
                struct max8997_muic_info *info)
{
    switch (info->pre_charger_type) {
    case MAX8997_CHARGER_TYPE_USB:
        extcon_set_cable_state(info->edev, "USB", false);
        break;
    case MAX8997_CHARGER_TYPE_DOWNSTREAM_PORT:
        extcon_set_cable_state(info->edev, "Charge-downstream", false);
        break;
    case MAX8997_CHARGER_TYPE_DEDICATED_CHG:
        extcon_set_cable_state(info->edev, "TA", false);
        break;
    case MAX8997_CHARGER_TYPE_500MA:
        extcon_set_cable_state(info->edev, "Slow-charger", false);
        break;
    case MAX8997_CHARGER_TYPE_1A:
        extcon_set_cable_state(info->edev, "Fast-charger", false);
        break;
    default:
        return -EINVAL;
        break;
    }

    return 0;
}

static int max8997_muic_handle_charger_type(struct max8997_muic_info *info,
                enum max8997_muic_charger_type charger_type)
{
    u8 adc;
    int ret;

    ret = max8997_read_reg(info->muic, MAX8997_MUIC_REG_STATUS1, &adc);
    if (ret) {
        dev_err(info->dev, "failed to read muic register\n");
        goto out;
    }

    switch (charger_type) {
    case MAX8997_CHARGER_TYPE_NONE:
        ret = max8997_muic_handle_charger_type_detach(info);
        break;
    case MAX8997_CHARGER_TYPE_USB:
        if ((adc & STATUS1_ADC_MASK) == MAX8997_ADC_OPEN) {
            max8997_muic_handle_usb(info,
                    MAX8997_USB_DEVICE, true);
        }
        break;
    case MAX8997_CHARGER_TYPE_DOWNSTREAM_PORT:
        extcon_set_cable_state(info->edev, "Charge-downstream", true);
        break;
    case MAX8997_CHARGER_TYPE_DEDICATED_CHG:
        extcon_set_cable_state(info->edev, "TA", true);
        break;
    case MAX8997_CHARGER_TYPE_500MA:
        extcon_set_cable_state(info->edev, "Slow-charger", true);
        break;
    case MAX8997_CHARGER_TYPE_1A:
        extcon_set_cable_state(info->edev, "Fast-charger", true);
        break;
    default:
        ret = -EINVAL;
        goto out;
    }

    info->pre_charger_type = charger_type;
out:
    return ret;
}

static void max8997_muic_irq_work(struct work_struct *work)
{
    struct max8997_muic_info *info = container_of(work,
            struct max8997_muic_info, irq_work);
    u8 status[2];
    u8 adc, chg_type;
    int irq_type = 0;
    int i, ret;

    mutex_lock(&info->mutex);

    ret = max8997_bulk_read(info->muic, MAX8997_MUIC_REG_STATUS1,
                2, status);
    if (ret) {
        dev_err(info->dev, "failed to read muic register\n");
        mutex_unlock(&info->mutex);
        return;
    }

    dev_dbg(info->dev, "%s: STATUS1:0x%x, 2:0x%x\n", __func__,
            status[0], status[1]);

    for (i = 0 ; i < ARRAY_SIZE(muic_irqs) ; i++)
        if (info->irq == muic_irqs[i].virq)
            irq_type = muic_irqs[i].irq;

    switch (irq_type) {
    case MAX8997_MUICIRQ_ADC:
        adc = status[0] & STATUS1_ADC_MASK;
        adc >>= STATUS1_ADC_SHIFT;

        max8997_muic_handle_adc(info, adc);
        break;
    case MAX8997_MUICIRQ_ChgTyp:
        chg_type = status[1] & STATUS2_CHGTYP_MASK;
        chg_type >>= STATUS2_CHGTYP_SHIFT;

        max8997_muic_handle_charger_type(info, chg_type);
        break;
    default:
        dev_info(info->dev, "misc interrupt: irq %d occurred\n",
                irq_type);
        break;
    }

    mutex_unlock(&info->mutex);

    return;
}

static irqreturn_t max8997_muic_irq_handler(int irq, void *data)
{
    struct max8997_muic_info *info = data;

    dev_dbg(info->dev, "irq:%d\n", irq);
    info->irq = irq;

    schedule_work(&info->irq_work);

    return IRQ_HANDLED;
}

static void max8997_muic_detect_dev(struct max8997_muic_info *info)
{
    int ret;
    u8 status[2], adc, chg_type;

    ret = max8997_bulk_read(info->muic, MAX8997_MUIC_REG_STATUS1,
                2, status);
    if (ret) {
        dev_err(info->dev, "failed to read muic register\n");
        return;
    }

    dev_info(info->dev, "STATUS1:0x%x, STATUS2:0x%x\n",
            status[0], status[1]);

    adc = status[0] & STATUS1_ADC_MASK;
    adc >>= STATUS1_ADC_SHIFT;

    chg_type = status[1] & STATUS2_CHGTYP_MASK;
    chg_type >>= STATUS2_CHGTYP_SHIFT;

    max8997_muic_handle_adc(info, adc);
    max8997_muic_handle_charger_type(info, chg_type);
}

static int __devinit max8997_muic_probe(struct platform_device *pdev)
{
    struct max8997_dev *max8997 = dev_get_drvdata(pdev->dev.parent);
    struct max8997_platform_data *pdata = dev_get_platdata(max8997->dev);
    struct max8997_muic_info *info;
    int ret, i;

    info = kzalloc(sizeof(struct max8997_muic_info), GFP_KERNEL);
    if (!info) {
        dev_err(&pdev->dev, "failed to allocate memory\n");
        ret = -ENOMEM;
        goto err_kfree;
    }

    info->dev = &pdev->dev;
    info->muic = max8997->muic;

    platform_set_drvdata(pdev, info);
    mutex_init(&info->mutex);

    INIT_WORK(&info->irq_work, max8997_muic_irq_work);

    for (i = 0; i < ARRAY_SIZE(muic_irqs); i++) {
        struct max8997_muic_irq *muic_irq = &muic_irqs[i];
        int virq = 0;

        virq = irq_create_mapping(max8997->irq_domain, muic_irq->irq);
        if (!virq)
            goto err_irq;
        muic_irq->virq = virq;

        ret = request_threaded_irq(virq, NULL,max8997_muic_irq_handler,
                0, muic_irq->name, info);
        if (ret) {
            dev_err(&pdev->dev,
                "failed: irq request (IRQ: %d,"
                " error :%d)\n",
                muic_irq->irq, ret);
            goto err_irq;
        }
    }

    /* External connector */
    info->edev = kzalloc(sizeof(struct extcon_dev), GFP_KERNEL);
    if (!info->edev) {
        dev_err(&pdev->dev, "failed to allocate memory for extcon\n");
        ret = -ENOMEM;
        goto err_irq;
    }
    info->edev->name = DEV_NAME;
    info->edev->supported_cable = max8997_extcon_cable;
    ret = extcon_dev_register(info->edev, NULL);
    if (ret) {
        dev_err(&pdev->dev, "failed to register extcon device\n");
        goto err_extcon;
    }

    /* Initialize registers according to platform data */
    if (pdata->muic_pdata) {
        struct max8997_muic_platform_data *mdata = info->muic_pdata;

        for (i = 0; i < mdata->num_init_data; i++) {
            max8997_write_reg(info->muic, mdata->init_data[i].addr,
                    mdata->init_data[i].data);
        }
    }

    /* Initial device detection */
    max8997_muic_detect_dev(info);

    return ret;

err_extcon:
    kfree(info->edev);
err_irq:
    while (--i >= 0)
        free_irq(muic_irqs[i].virq, info);
    kfree(info);
err_kfree:
    return ret;
}

static int __devexit max8997_muic_remove(struct platform_device *pdev)
{
    struct max8997_muic_info *info = platform_get_drvdata(pdev);
    int i;

    for (i = 0; i < ARRAY_SIZE(muic_irqs); i++)
        free_irq(muic_irqs[i].virq, info);
    cancel_work_sync(&info->irq_work);

    extcon_dev_unregister(info->edev);

    kfree(info->edev);
    kfree(info);

    return 0;
}

static struct platform_driver max8997_muic_driver = {
    .driver     = {
        .name   = DEV_NAME,
        .owner  = THIS_MODULE,
    },
    .probe      = max8997_muic_probe,
    .remove     = __devexit_p(max8997_muic_remove),
};

module_platform_driver(max8997_muic_driver);

MODULE_DESCRIPTION("Maxim MAX8997 Extcon driver");
MODULE_AUTHOR("Donggeun Kim <[email protected]>");
MODULE_LICENSE("GPL");