mfd: twl4030-core irq simplification

[linux-2.6/libata-dev.git] / drivers / mfd / twl4030-core.c

/*
 * twl4030_core.c - driver for TWL4030/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/kernel_stat.h>
#include <linux/init.h>
#include <linux/mutex.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/random.h>
#include <linux/kthread.h>
#include <linux/platform_device.h>
#include <linux/clk.h>

#include <linux/i2c.h>
#include <linux/i2c/twl4030.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                     "twl4030"

#if defined(CONFIG_TWL4030_BCI_BATTERY) || \
        defined(CONFIG_TWL4030_BCI_BATTERY_MODULE)
#define twl_has_bci()           true
#else
#define twl_has_bci()           false
#endif

#if defined(CONFIG_KEYBOARD_TWL4030) || defined(CONFIG_KEYBOARD_TWL4030_MODULE)
#define twl_has_keypad()        true
#else
#define twl_has_keypad()        false
#endif

#if defined(CONFIG_GPIO_TWL4030) || defined(CONFIG_GPIO_TWL4030_MODULE)
#define twl_has_gpio()  true
#else
#define twl_has_gpio()  false
#endif

#if defined(CONFIG_TWL4030_MADC) || defined(CONFIG_TWL4030_MADC_MODULE)
#define twl_has_madc()  true
#else
#define twl_has_madc()  false
#endif

#if defined(CONFIG_RTC_DRV_TWL4030) || defined(CONFIG_RTC_DRV_TWL4030_MODULE)
#define twl_has_rtc()   true
#else
#define twl_has_rtc()   false
#endif

#if defined(CONFIG_TWL4030_USB) || defined(CONFIG_TWL4030_USB_MODULE)
#define twl_has_usb()   true
#else
#define twl_has_usb()   false
#endif

static inline void activate_irq(int irq)
{
#ifdef CONFIG_ARM
        /* ARM requires an extra step to clear IRQ_NOREQUEST, which it
         * sets on behalf of every irq_chip.  Also sets IRQ_NOPROBE.
         */
        set_irq_flags(irq, IRQF_VALID);
#else
        /* same effect on other architectures */
        set_irq_noprobe(irq);
#endif
}

/* Primary Interrupt Handler on TWL4030 Registers */

/* Register Definitions */

#define REG_PIH_ISR_P1                  (0x1)
#define REG_PIH_ISR_P2                  (0x2)
#define REG_PIH_SIR                     (0x3)

/* Triton Core internal information (BEGIN) */

/* Last - for index max*/
#define TWL4030_MODULE_LAST             TWL4030_MODULE_SECURED_REG

#define TWL4030_NUM_SLAVES              4


/* 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_PWM0            0x00F8
#define TWL4030_BASEADD_PWM1            0x00FB
#define TWL4030_BASEADD_PWMA            0x00EF
#define TWL4030_BASEADD_PWMB            0x00F1
#define TWL4030_BASEADD_KEYPAD          0x00D2

/* 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_BASEADD_RTC             0x001C
#define TWL4030_BASEADD_SECURED_REG     0x0000

/* Triton Core internal information (END) */


/* Few power values */
#define R_CFG_BOOT                      0x05
#define R_PROTECT_KEY                   0x0E

/* access control values for R_PROTECT_KEY */
#define KEY_UNLOCK1                     0xce
#define KEY_UNLOCK2                     0xec
#define KEY_LOCK                        0x00

/* 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)


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

/**
 * struct twl4030_mod_iregs - TWL module IMR/ISR regs to mask/clear at init
 * @mod_no: TWL4030 module number (e.g., TWL4030_MODULE_GPIO)
 * @sih_ctrl: address of module SIH_CTRL register
 * @reg_cnt: number of IMR/ISR regs
 * @imrs: pointer to array of TWL module interrupt mask register indices
 * @isrs: pointer to array of TWL module interrupt status register indices
 *
 * Ties together TWL4030 modules and lists of IMR/ISR registers to mask/clear
 * during twl_init_irq().
 */
struct twl4030_mod_iregs {
        const u8 mod_no;
        const u8 sih_ctrl;
        const u8 reg_cnt;
        const u8 *imrs;
        const u8 *isrs;
};

/* TWL4030 INT module interrupt mask registers */
static const u8 __initconst twl4030_int_imr_regs[] = {
        TWL4030_INT_PWR_IMR1,
        TWL4030_INT_PWR_IMR2,
};

/* TWL4030 INT module interrupt status registers */
static const u8 __initconst twl4030_int_isr_regs[] = {
        TWL4030_INT_PWR_ISR1,
        TWL4030_INT_PWR_ISR2,
};

/* TWL4030 INTERRUPTS module interrupt mask registers */
static const u8 __initconst twl4030_interrupts_imr_regs[] = {
        TWL4030_INTERRUPTS_BCIIMR1A,
        TWL4030_INTERRUPTS_BCIIMR1B,
        TWL4030_INTERRUPTS_BCIIMR2A,
        TWL4030_INTERRUPTS_BCIIMR2B,
};

/* TWL4030 INTERRUPTS module interrupt status registers */
static const u8 __initconst twl4030_interrupts_isr_regs[] = {
        TWL4030_INTERRUPTS_BCIISR1A,
        TWL4030_INTERRUPTS_BCIISR1B,
        TWL4030_INTERRUPTS_BCIISR2A,
        TWL4030_INTERRUPTS_BCIISR2B,
};

/* TWL4030 MADC module interrupt mask registers */
static const u8 __initconst twl4030_madc_imr_regs[] = {
        TWL4030_MADC_IMR1,
        TWL4030_MADC_IMR2,
};

/* TWL4030 MADC module interrupt status registers */
static const u8 __initconst twl4030_madc_isr_regs[] = {
        TWL4030_MADC_ISR1,
        TWL4030_MADC_ISR2,
};

/* TWL4030 keypad module interrupt mask registers */
static const u8 __initconst twl4030_keypad_imr_regs[] = {
        TWL4030_KEYPAD_KEYP_IMR1,
        TWL4030_KEYPAD_KEYP_IMR2,
};

/* TWL4030 keypad module interrupt status registers */
static const u8 __initconst twl4030_keypad_isr_regs[] = {
        TWL4030_KEYPAD_KEYP_ISR1,
        TWL4030_KEYPAD_KEYP_ISR2,
};

/* TWL4030 GPIO module interrupt mask registers */
static const u8 __initconst twl4030_gpio_imr_regs[] = {
        REG_GPIO_IMR1A,
        REG_GPIO_IMR1B,
        REG_GPIO_IMR2A,
        REG_GPIO_IMR2B,
        REG_GPIO_IMR3A,
        REG_GPIO_IMR3B,
};

/* TWL4030 GPIO module interrupt status registers */
static const u8 __initconst twl4030_gpio_isr_regs[] = {
        REG_GPIO_ISR1A,
        REG_GPIO_ISR1B,
        REG_GPIO_ISR2A,
        REG_GPIO_ISR2B,
        REG_GPIO_ISR3A,
        REG_GPIO_ISR3B,
};

/* TWL4030 modules that have IMR/ISR registers that must be masked/cleared */
static const struct twl4030_mod_iregs __initconst twl4030_mod_regs[] = {
        {
                .mod_no   = TWL4030_MODULE_INT,
                .sih_ctrl = TWL4030_INT_PWR_SIH_CTRL,
                .reg_cnt  = ARRAY_SIZE(twl4030_int_imr_regs),
                .imrs     = twl4030_int_imr_regs,
                .isrs     = twl4030_int_isr_regs,
        },
        {
                .mod_no   = TWL4030_MODULE_INTERRUPTS,
                .sih_ctrl = TWL4030_INTERRUPTS_BCISIHCTRL,
                .reg_cnt  = ARRAY_SIZE(twl4030_interrupts_imr_regs),
                .imrs     = twl4030_interrupts_imr_regs,
                .isrs     = twl4030_interrupts_isr_regs,
        },
        {
                .mod_no   = TWL4030_MODULE_MADC,
                .sih_ctrl = TWL4030_MADC_SIH_CTRL,
                .reg_cnt  = ARRAY_SIZE(twl4030_madc_imr_regs),
                .imrs     = twl4030_madc_imr_regs,
                .isrs     = twl4030_madc_isr_regs,
        },
        {
                .mod_no   = TWL4030_MODULE_KEYPAD,
                .sih_ctrl = TWL4030_KEYPAD_KEYP_SIH_CTRL,
                .reg_cnt  = ARRAY_SIZE(twl4030_keypad_imr_regs),
                .imrs     = twl4030_keypad_imr_regs,
                .isrs     = twl4030_keypad_isr_regs,
        },
        {
                .mod_no   = TWL4030_MODULE_GPIO,
                .sih_ctrl = REG_GPIO_SIH_CTRL,
                .reg_cnt  = ARRAY_SIZE(twl4030_gpio_imr_regs),
                .imrs     = twl4030_gpio_imr_regs,
                .isrs     = twl4030_gpio_isr_regs,
        },
};

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

/* is driver active, bound to a chip? */
static bool inuse;

/* Structure for each TWL4030 Slave */
struct twl4030_client {
        struct i2c_client *client;
        u8 address;

        /* max numb of i2c_msg required is for read =2 */
        struct i2c_msg xfer_msg[2];

        /* To lock access to xfer_msg */
        struct mutex xfer_lock;
};

static struct twl4030_client twl4030_modules[TWL4030_NUM_SLAVES];


/* mapping the module id to slave id and base address */
struct twl4030mapping {
        unsigned char sid;      /* Slave ID */
        unsigned char base;     /* base address */
};

static struct twl4030mapping twl4030_map[TWL4030_MODULE_LAST + 1] = {
        /*
         * NOTE:  don't change this table without updating the
         * <linux/i2c/twl4030.h> defines for TWL4030_MODULE_*
         * so they continue to match the order in this table.
         */

        { 0, TWL4030_BASEADD_USB },

        { 1, TWL4030_BASEADD_AUDIO_VOICE },
        { 1, TWL4030_BASEADD_GPIO },
        { 1, TWL4030_BASEADD_INTBR },
        { 1, TWL4030_BASEADD_PIH },
        { 1, TWL4030_BASEADD_TEST },

        { 2, TWL4030_BASEADD_KEYPAD },
        { 2, TWL4030_BASEADD_MADC },
        { 2, TWL4030_BASEADD_INTERRUPTS },
        { 2, TWL4030_BASEADD_LED },
        { 2, TWL4030_BASEADD_MAIN_CHARGE },
        { 2, TWL4030_BASEADD_PRECHARGE },
        { 2, TWL4030_BASEADD_PWM0 },
        { 2, TWL4030_BASEADD_PWM1 },
        { 2, TWL4030_BASEADD_PWMA },
        { 2, TWL4030_BASEADD_PWMB },

        { 3, TWL4030_BASEADD_BACKUP },
        { 3, TWL4030_BASEADD_INT },
        { 3, TWL4030_BASEADD_PM_MASTER },
        { 3, TWL4030_BASEADD_PM_RECEIVER },
        { 3, TWL4030_BASEADD_RTC },
        { 3, TWL4030_BASEADD_SECURED_REG },
};

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

/*
 * TWL4030 doesn't have PIH mask, hence dummy function for mask
 * and unmask of the (eight) interrupts reported at that level ...
 * masking is only available from SIH (secondary) modules.
 */

static void twl4030_i2c_ackirq(unsigned int irq)
{
}

static void twl4030_i2c_disableint(unsigned int irq)
{
}

static void twl4030_i2c_enableint(unsigned int irq)
{
}

static struct irq_chip twl4030_irq_chip = {
        .name   = "twl4030",
        .ack    = twl4030_i2c_ackirq,
        .mask   = twl4030_i2c_disableint,
        .unmask = twl4030_i2c_enableint,
};

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

/* Exported Functions */

/**
 * twl4030_i2c_write - Writes a n bit register in TWL4030
 * @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
 *
 * IMPORTANT: for 'value' parameter: Allocate value num_bytes+1 and
 * valid data starts at Offset 1.
 *
 * Returns the result of operation - 0 is success
 */
int twl4030_i2c_write(u8 mod_no, u8 *value, u8 reg, u8 num_bytes)
{
        int ret;
        int sid;
        struct twl4030_client *twl;
        struct i2c_msg *msg;

        if (unlikely(mod_no > TWL4030_MODULE_LAST)) {
                pr_err("%s: invalid module number %d\n", DRIVER_NAME, mod_no);
                return -EPERM;
        }
        sid = twl4030_map[mod_no].sid;
        twl = &twl4030_modules[sid];

        if (unlikely(!inuse)) {
                pr_err("%s: client %d is not initialized\n", DRIVER_NAME, sid);
                return -EPERM;
        }
        mutex_lock(&twl->xfer_lock);
        /*
         * [MSG1]: fill the register address data
         * fill the data Tx buffer
         */
        msg = &twl->xfer_msg[0];
        msg->addr = twl->address;
        msg->len = num_bytes + 1;
        msg->flags = 0;
        msg->buf = value;
        /* over write the first byte of buffer with the register address */
        *value = twl4030_map[mod_no].base + reg;
        ret = i2c_transfer(twl->client->adapter, twl->xfer_msg, 1);
        mutex_unlock(&twl->xfer_lock);

        /* i2cTransfer returns num messages.translate it pls.. */
        if (ret >= 0)
                ret = 0;
        return ret;
}
EXPORT_SYMBOL(twl4030_i2c_write);

/**
 * twl4030_i2c_read - Reads a n bit register in TWL4030
 * @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 twl4030_i2c_read(u8 mod_no, u8 *value, u8 reg, u8 num_bytes)
{
        int ret;
        u8 val;
        int sid;
        struct twl4030_client *twl;
        struct i2c_msg *msg;

        if (unlikely(mod_no > TWL4030_MODULE_LAST)) {
                pr_err("%s: invalid module number %d\n", DRIVER_NAME, mod_no);
                return -EPERM;
        }
        sid = twl4030_map[mod_no].sid;
        twl = &twl4030_modules[sid];

        if (unlikely(!inuse)) {
                pr_err("%s: client %d is not initialized\n", DRIVER_NAME, sid);
                return -EPERM;
        }
        mutex_lock(&twl->xfer_lock);
        /* [MSG1] fill the register address data */
        msg = &twl->xfer_msg[0];
        msg->addr = twl->address;
        msg->len = 1;
        msg->flags = 0; /* Read the register value */
        val = twl4030_map[mod_no].base + reg;
        msg->buf = &val;
        /* [MSG2] fill the data rx buffer */
        msg = &twl->xfer_msg[1];
        msg->addr = twl->address;
        msg->flags = I2C_M_RD;  /* Read the register value */
        msg->len = num_bytes;   /* only n bytes */
        msg->buf = value;
        ret = i2c_transfer(twl->client->adapter, twl->xfer_msg, 2);
        mutex_unlock(&twl->xfer_lock);

        /* i2cTransfer returns num messages.translate it pls.. */
        if (ret >= 0)
                ret = 0;
        return ret;
}
EXPORT_SYMBOL(twl4030_i2c_read);

/**
 * twl4030_i2c_write_u8 - Writes a 8 bit register in TWL4030
 * @mod_no: module number
 * @value: the value to be written 8 bit
 * @reg: register address (just offset will do)
 *
 * Returns result of operation - 0 is success
 */
int twl4030_i2c_write_u8(u8 mod_no, u8 value, u8 reg)
{

        /* 2 bytes offset 1 contains the data offset 0 is used by i2c_write */
        u8 temp_buffer[2] = { 0 };
        /* offset 1 contains the data */
        temp_buffer[1] = value;
        return twl4030_i2c_write(mod_no, temp_buffer, reg, 1);
}
EXPORT_SYMBOL(twl4030_i2c_write_u8);

/**
 * twl4030_i2c_read_u8 - Reads a 8 bit register from TWL4030
 * @mod_no: module number
 * @value: the value read 8 bit
 * @reg: register address (just offset will do)
 *
 * Returns result of operation - 0 is success
 */
int twl4030_i2c_read_u8(u8 mod_no, u8 *value, u8 reg)
{
        return twl4030_i2c_read(mod_no, value, reg, 1);
}
EXPORT_SYMBOL(twl4030_i2c_read_u8);

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

static unsigned twl4030_irq_base;

static struct completion irq_event;

/*
 * This thread processes interrupts reported by the Primary Interrupt Handler.
 */
static int twl4030_irq_thread(void *data)
{
        long irq = (long)data;
        irq_desc_t *desc = irq_desc + irq;
        static unsigned i2c_errors;
        const static unsigned max_i2c_errors = 100;

        current->flags |= PF_NOFREEZE;

        while (!kthread_should_stop()) {
                int ret;
                int module_irq;
                u8 pih_isr;

                /* Wait for IRQ, then read PIH irq status (also blocking) */
                wait_for_completion_interruptible(&irq_event);

                ret = twl4030_i2c_read_u8(TWL4030_MODULE_PIH, &pih_isr,
                                          REG_PIH_ISR_P1);
                if (ret) {
                        pr_warning("%s: I2C error %d reading PIH ISR\n",
                                        DRIVER_NAME, ret);
                        if (++i2c_errors >= max_i2c_errors) {
                                printk(KERN_ERR "Maximum I2C error count"
                                                " exceeded.  Terminating %s.\n",
                                                __func__);
                                break;
                        }
                        complete(&irq_event);
                        continue;
                }

                /* these handlers deal with the relevant SIH irq status */
                local_irq_disable();
                for (module_irq = twl4030_irq_base;
                                pih_isr;
                                pih_isr >>= 1, module_irq++) {
                        if (pih_isr & 0x1) {
                                irq_desc_t *d = irq_desc + module_irq;

                                d->handle_irq(module_irq, d);
                        }
                }
                local_irq_enable();

                desc->chip->unmask(irq);
        }

        return 0;
}

/*
 * do_twl4030_irq() is the desc->handle method for the twl4030 interrupt.
 * This is a chained interrupt, so there is no desc->action method for it.
 * Now we need to query the interrupt controller in the twl4030 to determine
 * which module is generating the interrupt request.  However, we can't do i2c
 * transactions in interrupt context, so we must defer that work to a kernel
 * thread.  All we do here is acknowledge and mask the interrupt and wakeup
 * the kernel thread.
 */
static void do_twl4030_irq(unsigned int irq, irq_desc_t *desc)
{
        const unsigned int cpu = smp_processor_id();

        /*
         * Earlier this was desc->triggered = 1;
         */
        desc->status |= IRQ_LEVEL;

        /*
         * Acknowledge, clear _AND_ disable the interrupt.
         */
        desc->chip->ack(irq);

        if (!desc->depth) {
                kstat_cpu(cpu).irqs[irq]++;

                complete(&irq_event);
        }
}

static struct task_struct * __init start_twl4030_irq_thread(long irq)
{
        struct task_struct *thread;

        init_completion(&irq_event);
        thread = kthread_run(twl4030_irq_thread, (void *)irq, "twl4030-irq");
        if (!thread)
                pr_err("%s: could not create twl4030 irq %ld thread!\n",
                       DRIVER_NAME, irq);

        return thread;
}

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

static int add_children(struct twl4030_platform_data *pdata)
{
        struct platform_device  *pdev = NULL;
        struct twl4030_client   *twl = NULL;
        int                     status = 0;

        if (twl_has_bci() && pdata->bci) {
                twl = &twl4030_modules[3];

                pdev = platform_device_alloc("twl4030_bci", -1);
                if (!pdev) {
                        pr_debug("%s: can't alloc bci dev\n", DRIVER_NAME);
                        status = -ENOMEM;
                        goto err;
                }

                if (status == 0) {
                        pdev->dev.parent = &twl->client->dev;
                        status = platform_device_add_data(pdev, pdata->bci,
                                        sizeof(*pdata->bci));
                        if (status < 0) {
                                dev_dbg(&twl->client->dev,
                                        "can't add bci data, %d\n",
                                        status);
                                goto err;
                        }
                }

                if (status == 0) {
                        struct resource r = {
                                .start = TWL4030_PWRIRQ_CHG_PRES,
                                .flags = IORESOURCE_IRQ,
                        };

                        status = platform_device_add_resources(pdev, &r, 1);
                }

                if (status == 0)
                        status = platform_device_add(pdev);

                if (status < 0) {
                        platform_device_put(pdev);
                        dev_dbg(&twl->client->dev,
                                        "can't create bci dev, %d\n",
                                        status);
                        goto err;
                }
        }

        if (twl_has_gpio() && pdata->gpio) {
                twl = &twl4030_modules[1];

                pdev = platform_device_alloc("twl4030_gpio", -1);
                if (!pdev) {
                        pr_debug("%s: can't alloc gpio dev\n", DRIVER_NAME);
                        status = -ENOMEM;
                        goto err;
                }

                /* more driver model init */
                if (status == 0) {
                        pdev->dev.parent = &twl->client->dev;
                        /* device_init_wakeup(&pdev->dev, 1); */

                        status = platform_device_add_data(pdev, pdata->gpio,
                                        sizeof(*pdata->gpio));
                        if (status < 0) {
                                dev_dbg(&twl->client->dev,
                                        "can't add gpio data, %d\n",
                                        status);
                                goto err;
                        }
                }

                /* GPIO module IRQ */
                if (status == 0) {
                        struct resource r = {
                                .start = pdata->irq_base + 0,
                                .flags = IORESOURCE_IRQ,
                        };

                        status = platform_device_add_resources(pdev, &r, 1);
                }

                if (status == 0)
                        status = platform_device_add(pdev);

                if (status < 0) {
                        platform_device_put(pdev);
                        dev_dbg(&twl->client->dev,
                                        "can't create gpio dev, %d\n",
                                        status);
                        goto err;
                }
        }

        if (twl_has_keypad() && pdata->keypad) {
                pdev = platform_device_alloc("twl4030_keypad", -1);
                if (pdev) {
                        twl = &twl4030_modules[2];
                        pdev->dev.parent = &twl->client->dev;
                        device_init_wakeup(&pdev->dev, 1);
                        status = platform_device_add_data(pdev, pdata->keypad,
                                        sizeof(*pdata->keypad));
                        if (status < 0) {
                                dev_dbg(&twl->client->dev,
                                        "can't add keypad data, %d\n",
                                        status);
                                platform_device_put(pdev);
                                goto err;
                        }
                        status = platform_device_add(pdev);
                        if (status < 0) {
                                platform_device_put(pdev);
                                dev_dbg(&twl->client->dev,
                                                "can't create keypad dev, %d\n",
                                                status);
                                goto err;
                        }
                } else {
                        pr_debug("%s: can't alloc keypad dev\n", DRIVER_NAME);
                        status = -ENOMEM;
                        goto err;
                }
        }

        if (twl_has_madc() && pdata->madc) {
                pdev = platform_device_alloc("twl4030_madc", -1);
                if (pdev) {
                        twl = &twl4030_modules[2];
                        pdev->dev.parent = &twl->client->dev;
                        device_init_wakeup(&pdev->dev, 1);
                        status = platform_device_add_data(pdev, pdata->madc,
                                        sizeof(*pdata->madc));
                        if (status < 0) {
                                platform_device_put(pdev);
                                dev_dbg(&twl->client->dev,
                                        "can't add madc data, %d\n",
                                        status);
                                goto err;
                        }
                        status = platform_device_add(pdev);
                        if (status < 0) {
                                platform_device_put(pdev);
                                dev_dbg(&twl->client->dev,
                                                "can't create madc dev, %d\n",
                                                status);
                                goto err;
                        }
                } else {
                        pr_debug("%s: can't alloc madc dev\n", DRIVER_NAME);
                        status = -ENOMEM;
                        goto err;
                }
        }

        if (twl_has_rtc()) {
                twl = &twl4030_modules[3];

                pdev = platform_device_alloc("twl4030_rtc", -1);
                if (!pdev) {
                        pr_debug("%s: can't alloc rtc dev\n", DRIVER_NAME);
                        status = -ENOMEM;
                } else {
                        pdev->dev.parent = &twl->client->dev;
                        device_init_wakeup(&pdev->dev, 1);
                }

                /*
                 * REVISIT platform_data here currently might use of
                 * "msecure" line ... but for now we just expect board
                 * setup to tell the chip "we are secure" at all times.
                 * Eventually, Linux might become more aware of such
                 * HW security concerns, and "least privilege".
                 */

                /* RTC module IRQ */
                if (status == 0) {
                        struct resource r = {
                                /* REVISIT don't hard-wire this stuff */
                                .start = TWL4030_PWRIRQ_RTC,
                                .flags = IORESOURCE_IRQ,
                        };

                        status = platform_device_add_resources(pdev, &r, 1);
                }

                if (status == 0)
                        status = platform_device_add(pdev);

                if (status < 0) {
                        platform_device_put(pdev);
                        dev_dbg(&twl->client->dev,
                                        "can't create rtc dev, %d\n",
                                        status);
                        goto err;
                }
        }

        if (twl_has_usb() && pdata->usb) {
                twl = &twl4030_modules[0];

                pdev = platform_device_alloc("twl4030_usb", -1);
                if (!pdev) {
                        pr_debug("%s: can't alloc usb dev\n", DRIVER_NAME);
                        status = -ENOMEM;
                        goto err;
                }

                if (status == 0) {
                        pdev->dev.parent = &twl->client->dev;
                        device_init_wakeup(&pdev->dev, 1);
                        status = platform_device_add_data(pdev, pdata->usb,
                                        sizeof(*pdata->usb));
                        if (status < 0) {
                                platform_device_put(pdev);
                                dev_dbg(&twl->client->dev,
                                        "can't add usb data, %d\n",
                                        status);
                                goto err;
                        }
                }

                if (status == 0) {
                        struct resource r = {
                                .start = TWL4030_PWRIRQ_USB_PRES,
                                .flags = IORESOURCE_IRQ,
                        };

                        status = platform_device_add_resources(pdev, &r, 1);
                }

                if (status == 0)
                        status = platform_device_add(pdev);

                if (status < 0) {
                        platform_device_put(pdev);
                        dev_dbg(&twl->client->dev,
                                        "can't create usb dev, %d\n",
                                        status);
                }
        }

err:
        if (status)
                pr_err("failed to add twl4030's children (status %d)\n", status);
        return status;
}

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

/*
 * 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 = twl4030_i2c_write_u8(TWL4030_MODULE_PM_MASTER, KEY_LOCK,
                        R_PROTECT_KEY);
        return e;
}

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

        e |= twl4030_i2c_write_u8(TWL4030_MODULE_PM_MASTER, KEY_UNLOCK1,
                        R_PROTECT_KEY);
        e |= twl4030_i2c_write_u8(TWL4030_MODULE_PM_MASTER, KEY_UNLOCK2,
                        R_PROTECT_KEY);
        return e;
}

static void __init clocks_init(void)
{
        int e = 0;
        struct clk *osc;
        u32 rate;
        u8 ctrl = HFCLK_FREQ_26_MHZ;

#if defined(CONFIG_ARCH_OMAP2) || defined(CONFIG_ARCH_OMAP3)
        if (cpu_is_omap2430())
                osc = clk_get(NULL, "osc_ck");
        else
                osc = clk_get(NULL, "osc_sys_ck");
#else
        /* REVISIT for non-OMAP systems, pass the clock rate from
         * board init code, using platform_data.
         */
        osc = ERR_PTR(-EIO);
#endif
        if (IS_ERR(osc)) {
                printk(KERN_WARNING "Skipping twl4030 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;
        e |= unprotect_pm_master();
        /* effect->MADC+USB ck en */
        e |= twl4030_i2c_write_u8(TWL4030_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);
}

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

/**
 * twl4030_i2c_clear_isr - clear TWL4030 SIH ISR regs via read + write
 * @mod_no: TWL4030 module number
 * @reg: register index to clear
 * @cor: value of the <module>_SIH_CTRL.COR bit (1 or 0)
 *
 * Either reads (cor == 1) or writes (cor == 0) to a TWL4030 interrupt
 * status register to ensure that any prior interrupts are cleared.
 * Returns the status from the I2C read operation.
 */
static int __init twl4030_i2c_clear_isr(u8 mod_no, u8 reg, u8 cor)
{
        u8 tmp;

        return (cor) ? twl4030_i2c_read_u8(mod_no, &tmp, reg) :
                twl4030_i2c_write_u8(mod_no, 0xff, reg);
}

/**
 * twl4030_read_cor_bit - are TWL module ISRs cleared by reads or writes?
 * @mod_no: TWL4030 module number
 * @reg: register index to clear
 *
 * Returns 1 if the TWL4030 SIH interrupt status registers (ISRs) for
 * the specified TWL module are cleared by reads, or 0 if cleared by
 * writes.
 */
static int twl4030_read_cor_bit(u8 mod_no, u8 reg)
{
        u8 tmp = 0;

        WARN_ON(twl4030_i2c_read_u8(mod_no, &tmp, reg) < 0);

        tmp &= TWL4030_SIH_CTRL_COR_MASK;
        tmp >>= __ffs(TWL4030_SIH_CTRL_COR_MASK);

        return tmp;
}

/**
 * twl4030_mask_clear_intrs - mask and clear all TWL4030 interrupts
 * @t: pointer to twl4030_mod_iregs array
 * @t_sz: ARRAY_SIZE(t) (starting at 1)
 *
 * Mask all TWL4030 interrupt mask registers (IMRs) and clear all
 * interrupt status registers (ISRs).  No return value, but will WARN if
 * any I2C operations fail.
 */
static void __init twl4030_mask_clear_intrs(const struct twl4030_mod_iregs *t,
                                            const u8 t_sz)
{
        int i, j;

        /*
         * N.B. - further efficiency is possible here.  Eight I2C
         * operations on BCI and GPIO modules are avoidable if I2C
         * burst read/write transactions were implemented.  Would
         * probably save about 1ms of boot time and a small amount of
         * power.
         */
        for (i = 0; i < t_sz; i++) {
                const struct twl4030_mod_iregs tmr = t[i];
                int cor;

                /* Are ISRs cleared by reads or writes? */
                cor = twl4030_read_cor_bit(tmr.mod_no, tmr.sih_ctrl);

                for (j = 0; j < tmr.reg_cnt; j++) {

                        /* Mask interrupts at the TWL4030 */
                        WARN_ON(twl4030_i2c_write_u8(tmr.mod_no, 0xff,
                                                     tmr.imrs[j]) < 0);

                        /* Clear TWL4030 ISRs */
                        WARN_ON(twl4030_i2c_clear_isr(tmr.mod_no,
                                                      tmr.isrs[j], cor) < 0);
                }
        }
}


static void twl_init_irq(int irq_num, unsigned irq_base, unsigned irq_end)
{
        int     i;

        /*
         * Mask and clear all TWL4030 interrupts since initially we do
         * not have any TWL4030 module interrupt handlers present
         */
        twl4030_mask_clear_intrs(twl4030_mod_regs,
                                 ARRAY_SIZE(twl4030_mod_regs));

        twl4030_irq_base = irq_base;

        /* install an irq handler for each of the PIH modules */
        for (i = irq_base; i < irq_end; i++) {
                set_irq_chip_and_handler(i, &twl4030_irq_chip,
                                handle_simple_irq);
                activate_irq(i);
        }

        /* install an irq handler to demultiplex the TWL4030 interrupt */
        set_irq_data(irq_num, start_twl4030_irq_thread(irq_num));
        set_irq_chained_handler(irq_num, do_twl4030_irq);
}

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

static int twl4030_remove(struct i2c_client *client)
{
        unsigned i;

        /* FIXME undo twl_init_irq() */
        if (twl4030_irq_base) {
                dev_err(&client->dev, "can't yet clean up IRQs?\n");
                return -ENOSYS;
        }

        for (i = 0; i < TWL4030_NUM_SLAVES; i++) {
                struct twl4030_client   *twl = &twl4030_modules[i];

                if (twl->client && twl->client != client)
                        i2c_unregister_device(twl->client);
                twl4030_modules[i].client = NULL;
        }
        inuse = false;
        return 0;
}

/* NOTE:  this driver only handles a single twl4030/tps659x0 chip */
static int
twl4030_probe(struct i2c_client *client, const struct i2c_device_id *id)
{
        int                             status;
        unsigned                        i;
        struct twl4030_platform_data    *pdata = client->dev.platform_data;

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

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

        if (inuse || twl4030_irq_base) {
                dev_dbg(&client->dev, "driver is already in use\n");
                return -EBUSY;
        }

        for (i = 0; i < TWL4030_NUM_SLAVES; i++) {
                struct twl4030_client   *twl = &twl4030_modules[i];

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

        /* setup clock framework */
        clocks_init();

        /* Maybe init the T2 Interrupt subsystem */
        if (client->irq
                        && pdata->irq_base
                        && pdata->irq_end > pdata->irq_base) {
                twl_init_irq(client->irq, pdata->irq_base, pdata->irq_end);
                dev_info(&client->dev, "IRQ %d chains IRQs %d..%d\n",
                                client->irq, pdata->irq_base, pdata->irq_end - 1);
        }

        status = add_children(pdata);
fail:
        if (status < 0)
                twl4030_remove(client);
        return status;
}

static const struct i2c_device_id twl4030_ids[] = {
        { "twl4030", 0 },       /* "Triton 2" */
        { "tps65950", 0 },      /* catalog version of twl4030 */
        { "tps65930", 0 },      /* fewer LDOs and DACs; no charger */
        { "tps65920", 0 },      /* fewer LDOs; no codec or charger */
        { "twl5030", 0 },       /* T2 updated */
        { /* end of list */ },
};
MODULE_DEVICE_TABLE(i2c, twl4030_ids);

/* One Client Driver , 4 Clients */
static struct i2c_driver twl4030_driver = {
        .driver.name    = DRIVER_NAME,
        .id_table       = twl4030_ids,
        .probe          = twl4030_probe,
        .remove         = twl4030_remove,
};

static int __init twl4030_init(void)
{
        return i2c_add_driver(&twl4030_driver);
}
subsys_initcall(twl4030_init);

static void __exit twl4030_exit(void)
{
        i2c_del_driver(&twl4030_driver);
}
module_exit(twl4030_exit);

MODULE_AUTHOR("Texas Instruments, Inc.");
MODULE_DESCRIPTION("I2C Core interface for TWL4030");
MODULE_LICENSE("GPL");