/*
 * twl_core.c - driver for TWL4030/TWL5030/TWL60X0/TPS659x0 PM
 * and audio CODEC devices
 *
 * Copyright (C) 2005-2006 Texas Instruments, Inc.
 *
 * Modifications to defer interrupt handling to a kernel thread:
 * Copyright (C) 2006 MontaVista Software, Inc.
 *
 * Based on tlv320aic23.c:
 * Copyright (c) by Kai Svahn <kai.svahn@nokia.com>
 *
 * Code cleanup and modifications to IRQ handler.
 * by syed khasim <x0khasim@ti.com>
 *
 * 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 */

#include <linux/init.h>
#include <linux/mutex.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/device.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/irq.h>
#include <linux/irqdomain.h>

#include <linux/regulator/machine.h>

#include <linux/i2c.h>
#include <linux/i2c/twl.h>

/* Register descriptions for audio */
#include <linux/mfd/twl4030-audio.h>

#include "twl-core.h"

/*
 * The TWL4030 "Triton 2" is one of a family of a multi-function "Power
 * Management and System Companion Device" chips originally designed for
 * use in OMAP2 and OMAP 3 based systems.  Its control interfaces use I2C,
 * often at around 3 Mbit/sec, including for interrupt handling.
 *
 * This driver core provides genirq support for the interrupts emitted,
 * by the various modules, and exports register access primitives.
 *
 * FIXME this driver currently requires use of the first interrupt line
 * (and associated registers).
 */

#define DRIVER_NAME                     "twl"

/* Triton Core internal information (BEGIN) */

/* Base Address defns for twl4030_map[] */

/* subchip/slave 0 - USB ID */
#define TWL4030_BASEADD_USB             0x0000

/* subchip/slave 1 - AUD ID */
#define TWL4030_BASEADD_AUDIO_VOICE     0x0000
#define TWL4030_BASEADD_GPIO            0x0098
#define TWL4030_BASEADD_INTBR           0x0085
#define TWL4030_BASEADD_PIH             0x0080
#define TWL4030_BASEADD_TEST            0x004C

/* subchip/slave 2 - AUX ID */
#define TWL4030_BASEADD_INTERRUPTS      0x00B9
#define TWL4030_BASEADD_LED             0x00EE
#define TWL4030_BASEADD_MADC            0x0000
#define TWL4030_BASEADD_MAIN_CHARGE     0x0074
#define TWL4030_BASEADD_PRECHARGE       0x00AA
#define TWL4030_BASEADD_PWM             0x00F8
#define TWL4030_BASEADD_KEYPAD          0x00D2

#define TWL5031_BASEADD_ACCESSORY       0x0074 /* Replaces Main Charge */
#define TWL5031_BASEADD_INTERRUPTS      0x00B9 /* Different than TWL4030's
                                                  one */

/* subchip/slave 3 - POWER ID */
#define TWL4030_BASEADD_BACKUP          0x0014
#define TWL4030_BASEADD_INT             0x002E
#define TWL4030_BASEADD_PM_MASTER       0x0036

#define TWL4030_BASEADD_PM_RECEIVER     0x005B
#define TWL4030_DCDC_GLOBAL_CFG         0x06
#define SMARTREFLEX_ENABLE              BIT(3)

#define TWL4030_BASEADD_RTC             0x001C
#define TWL4030_BASEADD_SECURED_REG     0x0000

/* Triton Core internal information (END) */


/* subchip/slave 0 0x48 - POWER */
#define TWL6030_BASEADD_RTC             0x0000
#define TWL6030_BASEADD_SECURED_REG     0x0017
#define TWL6030_BASEADD_PM_MASTER       0x001F
#define TWL6030_BASEADD_PM_SLAVE_MISC   0x0030 /* PM_RECEIVER */
#define TWL6030_BASEADD_PM_MISC         0x00E2
#define TWL6030_BASEADD_PM_PUPD         0x00F0

/* subchip/slave 1 0x49 - FEATURE */
#define TWL6030_BASEADD_USB             0x0000
#define TWL6030_BASEADD_GPADC_CTRL      0x002E
#define TWL6030_BASEADD_AUX             0x0090
#define TWL6030_BASEADD_PWM             0x00BA
#define TWL6030_BASEADD_GASGAUGE        0x00C0
#define TWL6030_BASEADD_PIH             0x00D0
#define TWL6030_BASEADD_CHARGER         0x00E0
#define TWL6032_BASEADD_CHARGER         0x00DA
#define TWL6030_BASEADD_LED             0x00F4

/* subchip/slave 2 0x4A - DFT */
#define TWL6030_BASEADD_DIEID           0x00C0

/* subchip/slave 3 0x4B - AUDIO */
#define TWL6030_BASEADD_AUDIO           0x0000
#define TWL6030_BASEADD_RSV             0x0000
#define TWL6030_BASEADD_ZERO            0x0000

/* Few power values */
#define R_CFG_BOOT                      0x05

/* some fields in R_CFG_BOOT */
#define HFCLK_FREQ_19p2_MHZ             (1 << 0)
#define HFCLK_FREQ_26_MHZ               (2 << 0)
#define HFCLK_FREQ_38p4_MHZ             (3 << 0)
#define HIGH_PERF_SQ                    (1 << 3)
#define CK32K_LOWPWR_EN                 (1 << 7)

/*----------------------------------------------------------------------*/

/* Structure for each TWL4030/TWL6030 Slave */
struct twl_client {
        struct i2c_client *client;
        struct regmap *regmap;
};

/* mapping the module id to slave id and base address */
struct twl_mapping {
        unsigned char sid;      /* Slave ID */
        unsigned char base;     /* base address */
};

struct twl_private {
        bool ready; /* The core driver is ready to be used */
        u32 twl_idcode; /* TWL IDCODE Register value */
        unsigned int twl_id;

        struct twl_mapping *twl_map;
        struct twl_client *twl_modules;
};

static struct twl_private *twl_priv;

static struct twl_mapping twl4030_map[] = {
        /*
         * NOTE:  don't change this table without updating the
         * <linux/i2c/twl.h> defines for TWL4030_MODULE_*
         * so they continue to match the order in this table.
         */

        /* Common IPs */
        { 0, TWL4030_BASEADD_USB },
        { 1, TWL4030_BASEADD_PIH },
        { 2, TWL4030_BASEADD_MAIN_CHARGE },
        { 3, TWL4030_BASEADD_PM_MASTER },
        { 3, TWL4030_BASEADD_PM_RECEIVER },

        { 3, TWL4030_BASEADD_RTC },
        { 2, TWL4030_BASEADD_PWM },
        { 2, TWL4030_BASEADD_LED },
        { 3, TWL4030_BASEADD_SECURED_REG },

        /* TWL4030 specific IPs */
        { 1, TWL4030_BASEADD_AUDIO_VOICE },
        { 1, TWL4030_BASEADD_GPIO },
        { 1, TWL4030_BASEADD_INTBR },
        { 1, TWL4030_BASEADD_TEST },
        { 2, TWL4030_BASEADD_KEYPAD },

        { 2, TWL4030_BASEADD_MADC },
        { 2, TWL4030_BASEADD_INTERRUPTS },
        { 2, TWL4030_BASEADD_PRECHARGE },
        { 3, TWL4030_BASEADD_BACKUP },
        { 3, TWL4030_BASEADD_INT },

        { 2, TWL5031_BASEADD_ACCESSORY },
        { 2, TWL5031_BASEADD_INTERRUPTS },
};

static const struct reg_default twl4030_49_defaults[] = {
        /* Audio Registers */
        { 0x01, 0x00}, /* CODEC_MODE    */
        { 0x02, 0x00}, /* OPTION        */
        /* 0x03  Unused */
        { 0x04, 0x00}, /* MICBIAS_CTL   */
        { 0x05, 0x00}, /* ANAMICL       */
        { 0x06, 0x00}, /* ANAMICR       */
        { 0x07, 0x00}, /* AVADC_CTL     */
        { 0x08, 0x00}, /* ADCMICSEL     */
        { 0x09, 0x00}, /* DIGMIXING     */
        { 0x0a, 0x0f}, /* ATXL1PGA      */
        { 0x0b, 0x0f}, /* ATXR1PGA      */
        { 0x0c, 0x0f}, /* AVTXL2PGA     */
        { 0x0d, 0x0f}, /* AVTXR2PGA     */
        { 0x0e, 0x00}, /* AUDIO_IF      */
        { 0x0f, 0x00}, /* VOICE_IF      */
        { 0x10, 0x3f}, /* ARXR1PGA      */
        { 0x11, 0x3f}, /* ARXL1PGA      */
        { 0x12, 0x3f}, /* ARXR2PGA      */
        { 0x13, 0x3f}, /* ARXL2PGA      */
        { 0x14, 0x25}, /* VRXPGA        */
        { 0x15, 0x00}, /* VSTPGA        */
        { 0x16, 0x00}, /* VRX2ARXPGA    */
        { 0x17, 0x00}, /* AVDAC_CTL     */
        { 0x18, 0x00}, /* ARX2VTXPGA    */
        { 0x19, 0x32}, /* ARXL1_APGA_CTL*/
        { 0x1a, 0x32}, /* ARXR1_APGA_CTL*/
        { 0x1b, 0x32}, /* ARXL2_APGA_CTL*/
        { 0x1c, 0x32}, /* ARXR2_APGA_CTL*/
        { 0x1d, 0x00}, /* ATX2ARXPGA    */
        { 0x1e, 0x00}, /* BT_IF         */
        { 0x1f, 0x55}, /* BTPGA         */
        { 0x20, 0x00}, /* BTSTPGA       */
        { 0x21, 0x00}, /* EAR_CTL       */
        { 0x22, 0x00}, /* HS_SEL        */
        { 0x23, 0x00}, /* HS_GAIN_SET   */
        { 0x24, 0x00}, /* HS_POPN_SET   */
        { 0x25, 0x00}, /* PREDL_CTL     */
        { 0x26, 0x00}, /* PREDR_CTL     */
        { 0x27, 0x00}, /* PRECKL_CTL    */
        { 0x28, 0x00}, /* PRECKR_CTL    */
        { 0x29, 0x00}, /* HFL_CTL       */
        { 0x2a, 0x00}, /* HFR_CTL       */
        { 0x2b, 0x05}, /* ALC_CTL       */
        { 0x2c, 0x00}, /* ALC_SET1      */
        { 0x2d, 0x00}, /* ALC_SET2      */
        { 0x2e, 0x00}, /* BOOST_CTL     */
        { 0x2f, 0x00}, /* SOFTVOL_CTL   */
        { 0x30, 0x13}, /* DTMF_FREQSEL  */
        { 0x31, 0x00}, /* DTMF_TONEXT1H */
        { 0x32, 0x00}, /* DTMF_TONEXT1L */
        { 0x33, 0x00}, /* DTMF_TONEXT2H */
        { 0x34, 0x00}, /* DTMF_TONEXT2L */
        { 0x35, 0x79}, /* DTMF_TONOFF   */
        { 0x36, 0x11}, /* DTMF_WANONOFF */
        { 0x37, 0x00}, /* I2S_RX_SCRAMBLE_H */
        { 0x38, 0x00}, /* I2S_RX_SCRAMBLE_M */
        { 0x39, 0x00}, /* I2S_RX_SCRAMBLE_L */
        { 0x3a, 0x06}, /* APLL_CTL */
        { 0x3b, 0x00}, /* DTMF_CTL */
        { 0x3c, 0x44}, /* DTMF_PGA_CTL2 (0x3C) */
        { 0x3d, 0x69}, /* DTMF_PGA_CTL1 (0x3D) */
        { 0x3e, 0x00}, /* MISC_SET_1 */
        { 0x3f, 0x00}, /* PCMBTMUX */
        /* 0x40 - 0x42  Unused */
        { 0x43, 0x00}, /* RX_PATH_SEL */
        { 0x44, 0x32}, /* VDL_APGA_CTL */
        { 0x45, 0x00}, /* VIBRA_CTL */
        { 0x46, 0x00}, /* VIBRA_SET */
        { 0x47, 0x00}, /* VIBRA_PWM_SET */
        { 0x48, 0x00}, /* ANAMIC_GAIN   */
        { 0x49, 0x00}, /* MISC_SET_2    */
        /* End of Audio Registers */
};

static bool twl4030_49_nop_reg(struct device *dev, unsigned int reg)
{
        switch (reg) {
        case 0x00:
        case 0x03:
        case 0x40:
        case 0x41:
        case 0x42:
                return false;
        default:
                return true;
        }
}

static const struct regmap_range twl4030_49_volatile_ranges[] = {
        regmap_reg_range(TWL4030_BASEADD_TEST, 0xff),
};

static const struct regmap_access_table twl4030_49_volatile_table = {
        .yes_ranges = twl4030_49_volatile_ranges,
        .n_yes_ranges = ARRAY_SIZE(twl4030_49_volatile_ranges),
};

static const struct regmap_config twl4030_regmap_config[4] = {
        {
                /* Address 0x48 */
                .reg_bits = 8,
                .val_bits = 8,
                .max_register = 0xff,
        },
        {
                /* Address 0x49 */
                .reg_bits = 8,
                .val_bits = 8,
                .max_register = 0xff,

                .readable_reg = twl4030_49_nop_reg,
                .writeable_reg = twl4030_49_nop_reg,

                .volatile_table = &twl4030_49_volatile_table,

                .reg_defaults = twl4030_49_defaults,
                .num_reg_defaults = ARRAY_SIZE(twl4030_49_defaults),
                .cache_type = REGCACHE_RBTREE,
        },
        {
                /* Address 0x4a */
                .reg_bits = 8,
                .val_bits = 8,
                .max_register = 0xff,
        },
        {
                /* Address 0x4b */
                .reg_bits = 8,
                .val_bits = 8,
                .max_register = 0xff,
        },
};

static struct twl_mapping twl6030_map[] = {
        /*
         * NOTE:  don't change this table without updating the
         * <linux/i2c/twl.h> defines for TWL4030_MODULE_*
         * so they continue to match the order in this table.
         */

        /* Common IPs */
        { 1, TWL6030_BASEADD_USB },
        { 1, TWL6030_BASEADD_PIH },
        { 1, TWL6030_BASEADD_CHARGER },
        { 0, TWL6030_BASEADD_PM_MASTER },
        { 0, TWL6030_BASEADD_PM_SLAVE_MISC },

        { 0, TWL6030_BASEADD_RTC },
        { 1, TWL6030_BASEADD_PWM },
        { 1, TWL6030_BASEADD_LED },
        { 0, TWL6030_BASEADD_SECURED_REG },

        /* TWL6030 specific IPs */
        { 0, TWL6030_BASEADD_ZERO },
        { 1, TWL6030_BASEADD_ZERO },
        { 2, TWL6030_BASEADD_ZERO },
        { 1, TWL6030_BASEADD_GPADC_CTRL },
        { 1, TWL6030_BASEADD_GASGAUGE },
};

static const struct regmap_config twl6030_regmap_config[3] = {
        {
                /* Address 0x48 */
                .reg_bits = 8,
                .val_bits = 8,
                .max_register = 0xff,
        },
        {
                /* Address 0x49 */
                .reg_bits = 8,
                .val_bits = 8,
                .max_register = 0xff,
        },
        {
                /* Address 0x4a */
                .reg_bits = 8,
                .val_bits = 8,
                .max_register = 0xff,
        },
};

/*----------------------------------------------------------------------*/

static inline int twl_get_num_slaves(void)
{
        if (twl_class_is_4030())
                return 4; /* TWL4030 class have four slave address */
        else
                return 3; /* TWL6030 class have three slave address */
}

static inline int twl_get_last_module(void)
{
        if (twl_class_is_4030())
                return TWL4030_MODULE_LAST;
        else
                return TWL6030_MODULE_LAST;
}

/* Exported Functions */

unsigned int twl_rev(void)
{
        return twl_priv ? twl_priv->twl_id : 0;
}
EXPORT_SYMBOL(twl_rev);

/**
 * twl_get_regmap - Get the regmap associated with the given module
 * @mod_no: module number
 *
 * Returns the regmap pointer or NULL in case of failure.
 */
static struct regmap *twl_get_regmap(u8 mod_no)
{
        int sid;
        struct twl_client *twl;

        if (unlikely(!twl_priv || !twl_priv->ready)) {
                pr_err("%s: not initialized\n", DRIVER_NAME);
                return NULL;
        }
        if (unlikely(mod_no >= twl_get_last_module())) {
                pr_err("%s: invalid module number %d\n", DRIVER_NAME, mod_no);
                return NULL;
        }

        sid = twl_priv->twl_map[mod_no].sid;
        twl = &twl_priv->twl_modules[sid];

        return twl->regmap;
}

/**
 * twl_i2c_write - Writes a n bit register in TWL4030/TWL5030/TWL60X0
 * @mod_no: module number
 * @value: an array of num_bytes+1 containing data to write
 * @reg: register address (just offset will do)
 * @num_bytes: number of bytes to transfer
 *
 * Returns the result of operation - 0 is success
 */
int twl_i2c_write(u8 mod_no, u8 *value, u8 reg, unsigned num_bytes)
{
        struct regmap *regmap = twl_get_regmap(mod_no);
        int ret;

        if (!regmap)
                return -EPERM;

        ret = regmap_bulk_write(regmap, twl_priv->twl_map[mod_no].base + reg,
                                value, num_bytes);

        if (ret)
                pr_err("%s: Write failed (mod %d, reg 0x%02x count %d)\n",
                       DRIVER_NAME, mod_no, reg, num_bytes);

        return ret;
}
EXPORT_SYMBOL(twl_i2c_write);

/**
 * twl_i2c_read - Reads a n bit register in TWL4030/TWL5030/TWL60X0
 * @mod_no: module number
 * @value: an array of num_bytes containing data to be read
 * @reg: register address (just offset will do)
 * @num_bytes: number of bytes to transfer
 *
 * Returns result of operation - num_bytes is success else failure.
 */
int twl_i2c_read(u8 mod_no, u8 *value, u8 reg, unsigned num_bytes)
{
        struct regmap *regmap = twl_get_regmap(mod_no);
        int ret;

        if (!regmap)
                return -EPERM;

        ret = regmap_bulk_read(regmap, twl_priv->twl_map[mod_no].base + reg,
                               value, num_bytes);

        if (ret)
                pr_err("%s: Read failed (mod %d, reg 0x%02x count %d)\n",
                       DRIVER_NAME, mod_no, reg, num_bytes);

        return ret;
}
EXPORT_SYMBOL(twl_i2c_read);

/**
 * twl_regcache_bypass - Configure the regcache bypass for the regmap associated
 *                       with the module
 * @mod_no: module number
 * @enable: Regcache bypass state
 *
 * Returns 0 else failure.
 */
int twl_set_regcache_bypass(u8 mod_no, bool enable)
{
        struct regmap *regmap = twl_get_regmap(mod_no);

        if (!regmap)
                return -EPERM;

        regcache_cache_bypass(regmap, enable);

        return 0;
}
EXPORT_SYMBOL(twl_set_regcache_bypass);

/*----------------------------------------------------------------------*/

/**
 * twl_read_idcode_register - API to read the IDCODE register.
 *
 * Unlocks the IDCODE register and read the 32 bit value.
 */
static int twl_read_idcode_register(void)
{
        int err;

        err = twl_i2c_write_u8(TWL4030_MODULE_INTBR, TWL_EEPROM_R_UNLOCK,
                                                REG_UNLOCK_TEST_REG);
        if (err) {
                pr_err("TWL4030 Unable to unlock IDCODE registers -%d\n", err);
                goto fail;
        }

        err = twl_i2c_read(TWL4030_MODULE_INTBR, (u8 *)(&twl_priv->twl_idcode),
                                                REG_IDCODE_7_0, 4);
        if (err) {
                pr_err("TWL4030: unable to read IDCODE -%d\n", err);
                goto fail;
        }

        err = twl_i2c_write_u8(TWL4030_MODULE_INTBR, 0x0, REG_UNLOCK_TEST_REG);
        if (err)
                pr_err("TWL4030 Unable to relock IDCODE registers -%d\n", err);
fail:
        return err;
}

/**
 * twl_get_type - API to get TWL Si type.
 *
 * Api to get the TWL Si type from IDCODE value.
 */
int twl_get_type(void)
{
        return TWL_SIL_TYPE(twl_priv->twl_idcode);
}
EXPORT_SYMBOL_GPL(twl_get_type);

/**
 * twl_get_version - API to get TWL Si version.
 *
 * Api to get the TWL Si version from IDCODE value.
 */
int twl_get_version(void)
{
        return TWL_SIL_REV(twl_priv->twl_idcode);
}
EXPORT_SYMBOL_GPL(twl_get_version);

/**
 * twl_get_hfclk_rate - API to get TWL external HFCLK clock rate.
 *
 * Api to get the TWL HFCLK rate based on BOOT_CFG register.
 */
int twl_get_hfclk_rate(void)
{
        u8 ctrl;
        int rate;

        twl_i2c_read_u8(TWL_MODULE_PM_MASTER, &ctrl, R_CFG_BOOT);

        switch (ctrl & 0x3) {
        case HFCLK_FREQ_19p2_MHZ:
                rate = 19200000;
                break;
        case HFCLK_FREQ_26_MHZ:
                rate = 26000000;
                break;
        case HFCLK_FREQ_38p4_MHZ:
                rate = 38400000;
                break;
        default:
                pr_err("TWL4030: HFCLK is not configured\n");
                rate = -EINVAL;
                break;
        }

        return rate;
}
EXPORT_SYMBOL_GPL(twl_get_hfclk_rate);

static struct device *
add_numbered_child(unsigned mod_no, const char *name, int num,
                void *pdata, unsigned pdata_len,
                bool can_wakeup, int irq0, int irq1)
{
        struct platform_device  *pdev;
        struct twl_client       *twl;
        int                     status, sid;

        if (unlikely(mod_no >= twl_get_last_module())) {
                pr_err("%s: invalid module number %d\n", DRIVER_NAME, mod_no);
                return ERR_PTR(-EPERM);
        }
        sid = twl_priv->twl_map[mod_no].sid;
        twl = &twl_priv->twl_modules[sid];

        pdev = platform_device_alloc(name, num);
        if (!pdev) {
                dev_dbg(&twl->client->dev, "can't alloc dev\n");
                status = -ENOMEM;
                goto err;
        }

        pdev->dev.parent = &twl->client->dev;

        if (pdata) {
                status = platform_device_add_data(pdev, pdata, pdata_len);
                if (status < 0) {
                        dev_dbg(&pdev->dev, "can't add platform_data\n");
                        goto err;
                }
        }

        if (irq0) {
                struct resource r[2] = {
                        { .start = irq0, .flags = IORESOURCE_IRQ, },
                        { .start = irq1, .flags = IORESOURCE_IRQ, },
                };

                status = platform_device_add_resources(pdev, r, irq1 ? 2 : 1);
                if (status < 0) {
                        dev_dbg(&pdev->dev, "can't add irqs\n");
                        goto err;
                }
        }

        status = platform_device_add(pdev);
        if (status == 0)
                device_init_wakeup(&pdev->dev, can_wakeup);

err:
        if (status < 0) {
                platform_device_put(pdev);
                dev_err(&twl->client->dev, "can't add %s dev\n", name);
                return ERR_PTR(status);
        }
        return &pdev->dev;
}

static inline struct device *add_child(unsigned mod_no, const char *name,
                void *pdata, unsigned pdata_len,
                bool can_wakeup, int irq0, int irq1)
{
        return add_numbered_child(mod_no, name, -1, pdata, pdata_len,
                can_wakeup, irq0, irq1);
}

static struct device *
add_regulator_linked(int num, struct regulator_init_data *pdata,
                struct regulator_consumer_supply *consumers,
                unsigned num_consumers, unsigned long features)
{
        struct twl_regulator_driver_data drv_data;

        /* regulator framework demands init_data ... */
        if (!pdata)
                return NULL;

        if (consumers) {
                pdata->consumer_supplies = consumers;
                pdata->num_consumer_supplies = num_consumers;
        }

        if (pdata->driver_data) {
                /* If we have existing drv_data, just add the flags */
                struct twl_regulator_driver_data *tmp;
                tmp = pdata->driver_data;
                tmp->features |= features;
        } else {
                /* add new driver data struct, used only during init */
                drv_data.features = features;
                drv_data.set_voltage = NULL;
                drv_data.get_voltage = NULL;
                drv_data.data = NULL;
                pdata->driver_data = &drv_data;
        }

        /* NOTE:  we currently ignore regulator IRQs, e.g. for short circuits */
        return add_numbered_child(TWL_MODULE_PM_MASTER, "twl_reg", num,
                pdata, sizeof(*pdata), false, 0, 0);
}

static struct device *
add_regulator(int num, struct regulator_init_data *pdata,
                unsigned long features)
{
        return add_regulator_linked(num, pdata, NULL, 0, features);
}

/*
 * NOTE:  We know the first 8 IRQs after pdata->base_irq are
 * for the PIH, and the next are for the PWR_INT SIH, since
 * that's how twl_init_irq() sets things up.
 */

static int
add_children(struct twl4030_platform_data *pdata, unsigned irq_base,
                unsigned long features)
{
        struct device   *child;

        if (IS_ENABLED(CONFIG_GPIO_TWL4030) && pdata->gpio) {
                child = add_child(TWL4030_MODULE_GPIO, "twl4030_gpio",
                                pdata->gpio, sizeof(*pdata->gpio),
                                false, irq_base + GPIO_INTR_OFFSET, 0);
                if (IS_ERR(child))
                        return PTR_ERR(child);
        }

        if (IS_ENABLED(CONFIG_KEYBOARD_TWL4030) && pdata->keypad) {
                child = add_child(TWL4030_MODULE_KEYPAD, "twl4030_keypad",
                                pdata->keypad, sizeof(*pdata->keypad),
                                true, irq_base + KEYPAD_INTR_OFFSET, 0);
                if (IS_ERR(child))
                        return PTR_ERR(child);
        }

        if (IS_ENABLED(CONFIG_TWL4030_MADC) && pdata->madc &&
            twl_class_is_4030()) {
                child = add_child(TWL4030_MODULE_MADC, "twl4030_madc",
                                pdata->madc, sizeof(*pdata->madc),
                                true, irq_base + MADC_INTR_OFFSET, 0);
                if (IS_ERR(child))
                        return PTR_ERR(child);
        }

        if (IS_ENABLED(CONFIG_RTC_DRV_TWL4030)) {
                /*
                 * REVISIT platform_data here currently might expose the
                 * "msecure" line ... but for now we just expect board
                 * setup to tell the chip "it's always ok to SET_TIME".
                 * Eventually, Linux might become more aware of such
                 * HW security concerns, and "least privilege".
                 */
                child = add_child(TWL_MODULE_RTC, "twl_rtc", NULL, 0,
                                true, irq_base + RTC_INTR_OFFSET, 0);
                if (IS_ERR(child))
                        return PTR_ERR(child);
        }

        if (IS_ENABLED(CONFIG_PWM_TWL)) {
                child = add_child(TWL_MODULE_PWM, "twl-pwm", NULL, 0,
                                  false, 0, 0);
                if (IS_ERR(child))
                        return PTR_ERR(child);
        }

        if (IS_ENABLED(CONFIG_PWM_TWL_LED)) {
                child = add_child(TWL_MODULE_LED, "twl-pwmled", NULL, 0,
                                  false, 0, 0);
                if (IS_ERR(child))
                        return PTR_ERR(child);
        }

        if (IS_ENABLED(CONFIG_TWL4030_USB) && pdata->usb &&
            twl_class_is_4030()) {

                static struct regulator_consumer_supply usb1v5 = {
                        .supply =       "usb1v5",
                };
                static struct regulator_consumer_supply usb1v8 = {
                        .supply =       "usb1v8",
                };
                static struct regulator_consumer_supply usb3v1[] = {
                        { .supply =     "usb3v1" },
                        { .supply =     "bci3v1" },
                };

        /* First add the regulators so that they can be used by transceiver */
                if (IS_ENABLED(CONFIG_REGULATOR_TWL4030)) {
                        /* this is a template that gets copied */
                        struct regulator_init_data usb_fixed = {
                                .constraints.valid_modes_mask =
                                        REGULATOR_MODE_NORMAL
                                        | REGULATOR_MODE_STANDBY,
                                .constraints.valid_ops_mask =
                                        REGULATOR_CHANGE_MODE
                                        | REGULATOR_CHANGE_STATUS,
                        };

                        child = add_regulator_linked(TWL4030_REG_VUSB1V5,
                                                      &usb_fixed, &usb1v5, 1,
                                                      features);
                        if (IS_ERR(child))
                                return PTR_ERR(child);

                        child = add_regulator_linked(TWL4030_REG_VUSB1V8,
                                                      &usb_fixed, &usb1v8, 1,
                                                      features);
                        if (IS_ERR(child))
                                return PTR_ERR(child);

                        child = add_regulator_linked(TWL4030_REG_VUSB3V1,
                                                      &usb_fixed, usb3v1, 2,
                                                      features);
                        if (IS_ERR(child))
                                return PTR_ERR(child);

                }

                child = add_child(TWL_MODULE_USB, "twl4030_usb",
                                pdata->usb, sizeof(*pdata->usb), true,
                                /* irq0 = USB_PRES, irq1 = USB */
                                irq_base + USB_PRES_INTR_OFFSET,
                                irq_base + USB_INTR_OFFSET);

                if (IS_ERR(child))
                        return PTR_ERR(child);

                /* we need to connect regulators to this transceiver */
                if (IS_ENABLED(CONFIG_REGULATOR_TWL4030) && child) {
                        usb1v5.dev_name = dev_name(child);
                        usb1v8.dev_name = dev_name(child);
                        usb3v1[0].dev_name = dev_name(child);
                }
        }

        if (IS_ENABLED(CONFIG_TWL4030_WATCHDOG) && twl_class_is_4030()) {
                child = add_child(TWL_MODULE_PM_RECEIVER, "twl4030_wdt", NULL,
                                  0, false, 0, 0);
                if (IS_ERR(child))
                        return PTR_ERR(child);
        }

        if (IS_ENABLED(CONFIG_INPUT_TWL4030_PWRBUTTON) && twl_class_is_4030()) {
                child = add_child(TWL_MODULE_PM_MASTER, "twl4030_pwrbutton",
                                  NULL, 0, true, irq_base + 8 + 0, 0);
                if (IS_ERR(child))
                        return PTR_ERR(child);
        }

        if (IS_ENABLED(CONFIG_MFD_TWL4030_AUDIO) && pdata->audio &&
            twl_class_is_4030()) {
                child = add_child(TWL4030_MODULE_AUDIO_VOICE, "twl4030-audio",
                                pdata->audio, sizeof(*pdata->audio),
                                false, 0, 0);
                if (IS_ERR(child))
                        return PTR_ERR(child);
        }

        /* twl4030 regulators */
        if (IS_ENABLED(CONFIG_REGULATOR_TWL4030) && twl_class_is_4030()) {
                child = add_regulator(TWL4030_REG_VPLL1, pdata->vpll1,
                                        features);
                if (IS_ERR(child))
                        return PTR_ERR(child);

                child = add_regulator(TWL4030_REG_VIO, pdata->vio,
                                        features);
                if (IS_ERR(child))
                        return PTR_ERR(child);

                child = add_regulator(TWL4030_REG_VDD1, pdata->vdd1,
                                        features);
                if (IS_ERR(child))
                        return PTR_ERR(child);

                child = add_regulator(TWL4030_REG_VDD2, pdata->vdd2,
                                        features);
                if (IS_ERR(child))
                        return PTR_ERR(child);

                child = add_regulator(TWL4030_REG_VMMC1, pdata->vmmc1,
                                        features);
                if (IS_ERR(child))
                        return PTR_ERR(child);

                child = add_regulator(TWL4030_REG_VDAC, pdata->vdac,
                                        features);
                if (IS_ERR(child))
                        return PTR_ERR(child);

                child = add_regulator((features & TWL4030_VAUX2)
                                        ? TWL4030_REG_VAUX2_4030
                                        : TWL4030_REG_VAUX2,
                                pdata->vaux2, features);
                if (IS_ERR(child))
                        return PTR_ERR(child);

                child = add_regulator(TWL4030_REG_VINTANA1, pdata->vintana1,
                                        features);
                if (IS_ERR(child))
                        return PTR_ERR(child);

                child = add_regulator(TWL4030_REG_VINTANA2, pdata->vintana2,
                                        features);
                if (IS_ERR(child))
                        return PTR_ERR(child);

                child = add_regulator(TWL4030_REG_VINTDIG, pdata->vintdig,
                                        features);
                if (IS_ERR(child))
                        return PTR_ERR(child);
        }

        /* maybe add LDOs that are omitted on cost-reduced parts */
        if (IS_ENABLED(CONFIG_REGULATOR_TWL4030) && !(features & TPS_SUBSET)
          && twl_class_is_4030()) {
                child = add_regulator(TWL4030_REG_VPLL2, pdata->vpll2,
                                        features);
                if (IS_ERR(child))
                        return PTR_ERR(child);

                child = add_regulator(TWL4030_REG_VMMC2, pdata->vmmc2,
                                        features);
                if (IS_ERR(child))
                        return PTR_ERR(child);

                child = add_regulator(TWL4030_REG_VSIM, pdata->vsim,
                                        features);
                if (IS_ERR(child))
                        return PTR_ERR(child);

                child = add_regulator(TWL4030_REG_VAUX1, pdata->vaux1,
                                        features);
                if (IS_ERR(child))
                        return PTR_ERR(child);

                child = add_regulator(TWL4030_REG_VAUX3, pdata->vaux3,
                                        features);
                if (IS_ERR(child))
                        return PTR_ERR(child);

                child = add_regulator(TWL4030_REG_VAUX4, pdata->vaux4,
                                        features);
                if (IS_ERR(child))
                        return PTR_ERR(child);
        }

        if (IS_ENABLED(CONFIG_CHARGER_TWL4030) && pdata->bci &&
                        !(features & (TPS_SUBSET | TWL5031))) {
                child = add_child(TWL_MODULE_MAIN_CHARGE, "twl4030_bci",
                                pdata->bci, sizeof(*pdata->bci), false,
                                /* irq0 = CHG_PRES, irq1 = BCI */
                                irq_base + BCI_PRES_INTR_OFFSET,
                                irq_base + BCI_INTR_OFFSET);
                if (IS_ERR(child))
                        return PTR_ERR(child);
        }

        if (IS_ENABLED(CONFIG_TWL4030_POWER) && pdata->power) {
                child = add_child(TWL_MODULE_PM_MASTER, "twl4030_power",
                                  pdata->power, sizeof(*pdata->power), false,
                                  0, 0);
                if (IS_ERR(child))
                        return PTR_ERR(child);
        }

        return 0;
}

/*----------------------------------------------------------------------*/

/*
 * These three functions initialize the on-chip clock framework,
 * letting it generate the right frequencies for USB, MADC, and
 * other purposes.
 */
static inline int __init protect_pm_master(void)
{
        int e = 0;

        e = twl_i2c_write_u8(TWL_MODULE_PM_MASTER, 0,
                             TWL4030_PM_MASTER_PROTECT_KEY);
        return e;
}

static inline int __init unprotect_pm_master(void)
{
        int e = 0;

        e |= twl_i2c_write_u8(TWL_MODULE_PM_MASTER, TWL4030_PM_MASTER_KEY_CFG1,
                              TWL4030_PM_MASTER_PROTECT_KEY);

        e |= twl_i2c_write_u8(TWL_MODULE_PM_MASTER, TWL4030_PM_MASTER_KEY_CFG2,
                              TWL4030_PM_MASTER_PROTECT_KEY);

        return e;
}

static void clocks_init(struct device *dev,
                        struct twl4030_clock_init_data *clock)
{
        int e = 0;
        struct clk *osc;
        u32 rate;
        u8 ctrl = HFCLK_FREQ_26_MHZ;

        osc = clk_get(dev, "fck");
        if (IS_ERR(osc)) {
                printk(KERN_WARNING "Skipping twl internal clock init and "
                                "using bootloader value (unknown osc rate)\n");
                return;
        }

        rate = clk_get_rate(osc);
        clk_put(osc);

        switch (rate) {
        case 19200000:
                ctrl = HFCLK_FREQ_19p2_MHZ;
                break;
        case 26000000:
                ctrl = HFCLK_FREQ_26_MHZ;
                break;
        case 38400000:
                ctrl = HFCLK_FREQ_38p4_MHZ;
                break;
        }

        ctrl |= HIGH_PERF_SQ;
        if (clock && clock->ck32k_lowpwr_enable)
                ctrl |= CK32K_LOWPWR_EN;

        e |= unprotect_pm_master();
        /* effect->MADC+USB ck en */
        e |= twl_i2c_write_u8(TWL_MODULE_PM_MASTER, ctrl, R_CFG_BOOT);
        e |= protect_pm_master();

        if (e < 0)
                pr_err("%s: clock init err [%d]\n", DRIVER_NAME, e);
}

/*----------------------------------------------------------------------*/


static int twl_remove(struct i2c_client *client)
{
        unsigned i, num_slaves;
        int status;

        if (twl_class_is_4030())
                status = twl4030_exit_irq();
        else
                status = twl6030_exit_irq();

        if (status < 0)
                return status;

        num_slaves = twl_get_num_slaves();
        for (i = 0; i < num_slaves; i++) {
                struct twl_client       *twl = &twl_priv->twl_modules[i];

                if (twl->client && twl->client != client)
                        i2c_unregister_device(twl->client);
                twl->client = NULL;
        }
        twl_priv->ready = false;
        return 0;
}

static struct of_dev_auxdata twl_auxdata_lookup[] = {
        OF_DEV_AUXDATA("ti,twl4030-gpio", 0, "twl4030-gpio", NULL),
        { /* sentinel */ },
};

/* NOTE: This driver only handles a single twl4030/tps659x0 chip */
static int
twl_probe(struct i2c_client *client, const struct i2c_device_id *id)
{
        struct twl4030_platform_data    *pdata = dev_get_platdata(&client->dev);
        struct device_node              *node = client->dev.of_node;
        struct platform_device          *pdev;
        const struct regmap_config      *twl_regmap_config;
        int                             irq_base = 0;
        int                             status;
        unsigned                        i, num_slaves;

        if (!node && !pdata) {
                dev_err(&client->dev, "no platform data\n");
                return -EINVAL;
        }

        if (twl_priv) {
                dev_dbg(&client->dev, "only one instance of %s allowed\n",
                        DRIVER_NAME);
                return -EBUSY;
        }

        pdev = platform_device_alloc(DRIVER_NAME, -1);
        if (!pdev) {
                dev_err(&client->dev, "can't alloc pdev\n");
                return -ENOMEM;
        }

        status = platform_device_add(pdev);
        if (status) {
                platform_device_put(pdev);
                return status;
        }

        if (i2c_check_functionality(client->adapter, I2C_FUNC_I2C) == 0) {
                dev_dbg(&client->dev, "can't talk I2C?\n");
                status = -EIO;
                goto free;
        }

        twl_priv = devm_kzalloc(&client->dev, sizeof(struct twl_private),
                                GFP_KERNEL);
        if (!twl_priv) {
                status = -ENOMEM;
                goto free;
        }

        if ((id->driver_data) & TWL6030_CLASS) {
                twl_priv->twl_id = TWL6030_CLASS_ID;
                twl_priv->twl_map = &twl6030_map[0];
                /* The charger base address is different in twl6032 */
                if ((id->driver_data) & TWL6032_SUBCLASS)
                        twl_priv->twl_map[TWL_MODULE_MAIN_CHARGE].base =
                                                        TWL6032_BASEADD_CHARGER;
                twl_regmap_config = twl6030_regmap_config;
        } else {
                twl_priv->twl_id = TWL4030_CLASS_ID;
                twl_priv->twl_map = &twl4030_map[0];
                twl_regmap_config = twl4030_regmap_config;
        }

        num_slaves = twl_get_num_slaves();
        twl_priv->twl_modules = devm_kzalloc(&client->dev,
                                         sizeof(struct twl_client) * num_slaves,
                                         GFP_KERNEL);
        if (!twl_priv->twl_modules) {
                status = -ENOMEM;
                goto free;
        }

        for (i = 0; i < num_slaves; i++) {
                struct twl_client *twl = &twl_priv->twl_modules[i];

                if (i == 0) {
                        twl->client = client;
                } else {
                        twl->client = i2c_new_dummy(client->adapter,
                                                    client->addr + i);
                        if (!twl->client) {
                                dev_err(&client->dev,
                                        "can't attach client %d\n", i);
                                status = -ENOMEM;
                                goto fail;
                        }
                }

                twl->regmap = devm_regmap_init_i2c(twl->client,
                                                   &twl_regmap_config[i]);
                if (IS_ERR(twl->regmap)) {
                        status = PTR_ERR(twl->regmap);
                        dev_err(&client->dev,
                                "Failed to allocate regmap %d, err: %d\n", i,
                                status);
                        goto fail;
                }
        }

        twl_priv->ready = true;

        /* setup clock framework */
        clocks_init(&pdev->dev, pdata ? pdata->clock : NULL);

        /* read TWL IDCODE Register */
        if (twl_class_is_4030()) {
                status = twl_read_idcode_register();
                WARN(status < 0, "Error: reading twl_idcode register value\n");
        }

        /* Maybe init the T2 Interrupt subsystem */
        if (client->irq) {
                if (twl_class_is_4030()) {
                        twl4030_init_chip_irq(id->name);
                        irq_base = twl4030_init_irq(&client->dev, client->irq);
                } else {
                        irq_base = twl6030_init_irq(&client->dev, client->irq);
                }

                if (irq_base < 0) {
                        status = irq_base;
                        goto fail;
                }
        }

        /*
         * Disable TWL4030/TWL5030 I2C Pull-up on I2C1 and I2C4(SR) interface.
         * Program I2C_SCL_CTRL_PU(bit 0)=0, I2C_SDA_CTRL_PU (bit 2)=0,
         * SR_I2C_SCL_CTRL_PU(bit 4)=0 and SR_I2C_SDA_CTRL_PU(bit 6)=0.
         *
         * Also, always enable SmartReflex bit as that's needed for omaps to
         * to do anything over I2C4 for voltage scaling even if SmartReflex
         * is disabled. Without the SmartReflex bit omap sys_clkreq idle
         * signal will never trigger for retention idle.
         */
        if (twl_class_is_4030()) {
                u8 temp;

                twl_i2c_read_u8(TWL4030_MODULE_INTBR, &temp, REG_GPPUPDCTR1);
                temp &= ~(SR_I2C_SDA_CTRL_PU | SR_I2C_SCL_CTRL_PU | \
                        I2C_SDA_CTRL_PU | I2C_SCL_CTRL_PU);
                twl_i2c_write_u8(TWL4030_MODULE_INTBR, temp, REG_GPPUPDCTR1);

                twl_i2c_read_u8(TWL_MODULE_PM_RECEIVER, &temp,
                                TWL4030_DCDC_GLOBAL_CFG);
                temp |= SMARTREFLEX_ENABLE;
                twl_i2c_write_u8(TWL_MODULE_PM_RECEIVER, temp,
                                 TWL4030_DCDC_GLOBAL_CFG);
        }

        if (node) {
                if (pdata)
                        twl_auxdata_lookup[0].platform_data = pdata->gpio;
                status = of_platform_populate(node, NULL, twl_auxdata_lookup,
                                              &client->dev);
        } else {
                status = add_children(pdata, irq_base, id->driver_data);
        }

fail:
        if (status < 0)
                twl_remove(client);
free:
        if (status < 0)
                platform_device_unregister(pdev);

        return status;
}

static const struct i2c_device_id twl_ids[] = {
        { "twl4030", TWL4030_VAUX2 },   /* "Triton 2" */
        { "twl5030", 0 },               /* T2 updated */
        { "twl5031", TWL5031 },         /* TWL5030 updated */
        { "tps65950", 0 },              /* catalog version of twl5030 */
        { "tps65930", TPS_SUBSET },     /* fewer LDOs and DACs; no charger */
        { "tps65920", TPS_SUBSET },     /* fewer LDOs; no codec or charger */
        { "tps65921", TPS_SUBSET },     /* fewer LDOs; no codec, no LED
                                           and vibrator. Charger in USB module*/
        { "twl6030", TWL6030_CLASS },   /* "Phoenix power chip" */
        { "twl6032", TWL6030_CLASS | TWL6032_SUBCLASS }, /* "Phoenix lite" */
        { /* end of list */ },
};
MODULE_DEVICE_TABLE(i2c, twl_ids);

/* One Client Driver , 4 Clients */
static struct i2c_driver twl_driver = {
        .driver.name    = DRIVER_NAME,
        .id_table       = twl_ids,
        .probe          = twl_probe,
        .remove         = twl_remove,
};

module_i2c_driver(twl_driver);

MODULE_AUTHOR("Texas Instruments, Inc.");
MODULE_DESCRIPTION("I2C Core interface for TWL");
MODULE_LICENSE("GPL");