tc3589x.c

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/*
 * Copyright (C) ST-Ericsson SA 2010
 *
 * License Terms: GNU General Public License, version 2
 * Author: Hanumath Prasad <[email protected]> for ST-Ericsson
 * Author: Rabin Vincent <[email protected]> for ST-Ericsson
 */

#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/irqdomain.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/of.h>
#include <linux/mfd/core.h>
#include <linux/mfd/tc3589x.h>

#define TC3589x_CLKMODE_MODCTL_SLEEP        0x0
#define TC3589x_CLKMODE_MODCTL_OPERATION    (1 << 0)

int tc3589x_reg_read(struct tc3589x *tc3589x, u8 reg)
{
    int ret;

    ret = i2c_smbus_read_byte_data(tc3589x->i2c, reg);
    if (ret < 0)
        dev_err(tc3589x->dev, "failed to read reg %#x: %d\n",
            reg, ret);

    return ret;
}
EXPORT_SYMBOL_GPL(tc3589x_reg_read);

int tc3589x_reg_write(struct tc3589x *tc3589x, u8 reg, u8 data)
{
    int ret;

    ret = i2c_smbus_write_byte_data(tc3589x->i2c, reg, data);
    if (ret < 0)
        dev_err(tc3589x->dev, "failed to write reg %#x: %d\n",
            reg, ret);

    return ret;
}
EXPORT_SYMBOL_GPL(tc3589x_reg_write);

int tc3589x_block_read(struct tc3589x *tc3589x, u8 reg, u8 length, u8 *values)
{
    int ret;

    ret = i2c_smbus_read_i2c_block_data(tc3589x->i2c, reg, length, values);
    if (ret < 0)
        dev_err(tc3589x->dev, "failed to read regs %#x: %d\n",
            reg, ret);

    return ret;
}
EXPORT_SYMBOL_GPL(tc3589x_block_read);

int tc3589x_block_write(struct tc3589x *tc3589x, u8 reg, u8 length,
            const u8 *values)
{
    int ret;

    ret = i2c_smbus_write_i2c_block_data(tc3589x->i2c, reg, length,
                         values);
    if (ret < 0)
        dev_err(tc3589x->dev, "failed to write regs %#x: %d\n",
            reg, ret);

    return ret;
}
EXPORT_SYMBOL_GPL(tc3589x_block_write);

int tc3589x_set_bits(struct tc3589x *tc3589x, u8 reg, u8 mask, u8 val)
{
    int ret;

    mutex_lock(&tc3589x->lock);

    ret = tc3589x_reg_read(tc3589x, reg);
    if (ret < 0)
        goto out;

    ret &= ~mask;
    ret |= val;

    ret = tc3589x_reg_write(tc3589x, reg, ret);

out:
    mutex_unlock(&tc3589x->lock);
    return ret;
}
EXPORT_SYMBOL_GPL(tc3589x_set_bits);

static struct resource gpio_resources[] = {
    {
        .start  = TC3589x_INT_GPIIRQ,
        .end    = TC3589x_INT_GPIIRQ,
        .flags  = IORESOURCE_IRQ,
    },
};

static struct resource keypad_resources[] = {
    {
        .start  = TC3589x_INT_KBDIRQ,
        .end    = TC3589x_INT_KBDIRQ,
        .flags  = IORESOURCE_IRQ,
    },
};

static struct mfd_cell tc3589x_dev_gpio[] = {
    {
        .name       = "tc3589x-gpio",
        .num_resources  = ARRAY_SIZE(gpio_resources),
        .resources  = &gpio_resources[0],
        .of_compatible  = "tc3589x-gpio",
    },
};

static struct mfd_cell tc3589x_dev_keypad[] = {
    {
        .name           = "tc3589x-keypad",
        .num_resources  = ARRAY_SIZE(keypad_resources),
        .resources      = &keypad_resources[0],
        .of_compatible  = "tc3589x-keypad",
    },
};

static irqreturn_t tc3589x_irq(int irq, void *data)
{
    struct tc3589x *tc3589x = data;
    int status;

again:
    status = tc3589x_reg_read(tc3589x, TC3589x_IRQST);
    if (status < 0)
        return IRQ_NONE;

    while (status) {
        int bit = __ffs(status);
        int virq = irq_create_mapping(tc3589x->domain, bit);

        handle_nested_irq(virq);
        status &= ~(1 << bit);
    }

    /*
     * A dummy read or write (to any register) appears to be necessary to
     * have the last interrupt clear (for example, GPIO IC write) take
     * effect. In such a case, recheck for any interrupt which is still
     * pending.
     */
    status = tc3589x_reg_read(tc3589x, TC3589x_IRQST);
    if (status)
        goto again;

    return IRQ_HANDLED;
}

static int tc3589x_irq_map(struct irq_domain *d, unsigned int virq,
                irq_hw_number_t hwirq)
{
    struct tc3589x *tc3589x = d->host_data;

    irq_set_chip_data(virq, tc3589x);
    irq_set_chip_and_handler(virq, &dummy_irq_chip,
                handle_edge_irq);
    irq_set_nested_thread(virq, 1);
#ifdef CONFIG_ARM
    set_irq_flags(virq, IRQF_VALID);
#else
    irq_set_noprobe(virq);
#endif

    return 0;
}

static void tc3589x_irq_unmap(struct irq_domain *d, unsigned int virq)
{
#ifdef CONFIG_ARM
    set_irq_flags(virq, 0);
#endif
    irq_set_chip_and_handler(virq, NULL, NULL);
    irq_set_chip_data(virq, NULL);
}

static struct irq_domain_ops tc3589x_irq_ops = {
        .map    = tc3589x_irq_map,
    .unmap  = tc3589x_irq_unmap,
        .xlate  = irq_domain_xlate_twocell,
};

static int tc3589x_irq_init(struct tc3589x *tc3589x, struct device_node *np)
{
    int base = tc3589x->irq_base;

    if (base) {
        tc3589x->domain = irq_domain_add_legacy(
            NULL, TC3589x_NR_INTERNAL_IRQS, base,
            0, &tc3589x_irq_ops, tc3589x);
    }
    else {
        tc3589x->domain = irq_domain_add_linear(
            np, TC3589x_NR_INTERNAL_IRQS,
            &tc3589x_irq_ops, tc3589x);
    }

    if (!tc3589x->domain) {
        dev_err(tc3589x->dev, "Failed to create irqdomain\n");
        return -ENOSYS;
    }

    return 0;
}

static int tc3589x_chip_init(struct tc3589x *tc3589x)
{
    int manf, ver, ret;

    manf = tc3589x_reg_read(tc3589x, TC3589x_MANFCODE);
    if (manf < 0)
        return manf;

    ver = tc3589x_reg_read(tc3589x, TC3589x_VERSION);
    if (ver < 0)
        return ver;

    if (manf != TC3589x_MANFCODE_MAGIC) {
        dev_err(tc3589x->dev, "unknown manufacturer: %#x\n", manf);
        return -EINVAL;
    }

    dev_info(tc3589x->dev, "manufacturer: %#x, version: %#x\n", manf, ver);

    /*
     * Put everything except the IRQ module into reset;
     * also spare the GPIO module for any pin initialization
     * done during pre-kernel boot
     */
    ret = tc3589x_reg_write(tc3589x, TC3589x_RSTCTRL,
                TC3589x_RSTCTRL_TIMRST
                | TC3589x_RSTCTRL_ROTRST
                | TC3589x_RSTCTRL_KBDRST);
    if (ret < 0)
        return ret;

    /* Clear the reset interrupt. */
    return tc3589x_reg_write(tc3589x, TC3589x_RSTINTCLR, 0x1);
}

static int __devinit tc3589x_device_init(struct tc3589x *tc3589x)
{
    int ret = 0;
    unsigned int blocks = tc3589x->pdata->block;

    if (blocks & TC3589x_BLOCK_GPIO) {
        ret = mfd_add_devices(tc3589x->dev, -1, tc3589x_dev_gpio,
                      ARRAY_SIZE(tc3589x_dev_gpio), NULL,
                      tc3589x->irq_base, tc3589x->domain);
        if (ret) {
            dev_err(tc3589x->dev, "failed to add gpio child\n");
            return ret;
        }
        dev_info(tc3589x->dev, "added gpio block\n");
    }

    if (blocks & TC3589x_BLOCK_KEYPAD) {
        ret = mfd_add_devices(tc3589x->dev, -1, tc3589x_dev_keypad,
                      ARRAY_SIZE(tc3589x_dev_keypad), NULL,
                      tc3589x->irq_base, tc3589x->domain);
        if (ret) {
            dev_err(tc3589x->dev, "failed to keypad child\n");
            return ret;
        }
        dev_info(tc3589x->dev, "added keypad block\n");
    }

    return ret;
}

static int tc3589x_of_probe(struct device_node *np,
            struct tc3589x_platform_data *pdata)
{
    struct device_node *child;

    for_each_child_of_node(np, child) {
        if (!strcmp(child->name, "tc3589x_gpio")) {
            pdata->block |= TC3589x_BLOCK_GPIO;
        }
        if (!strcmp(child->name, "tc3589x_keypad")) {
            pdata->block |= TC3589x_BLOCK_KEYPAD;
        }
    }

    return 0;
}

static int __devinit tc3589x_probe(struct i2c_client *i2c,
                   const struct i2c_device_id *id)
{
    struct tc3589x_platform_data *pdata = i2c->dev.platform_data;
    struct device_node *np = i2c->dev.of_node;
    struct tc3589x *tc3589x;
    int ret;

    if (!pdata) {
        if (np) {
            pdata = devm_kzalloc(&i2c->dev, sizeof(*pdata), GFP_KERNEL);
            if (!pdata)
                return -ENOMEM;

            ret = tc3589x_of_probe(np, pdata);
            if (ret)
                return ret;
        }
        else {
            dev_err(&i2c->dev, "No platform data or DT found\n");
            return -EINVAL;
        }
    }

    if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA
                     | I2C_FUNC_SMBUS_I2C_BLOCK))
        return -EIO;

    tc3589x = kzalloc(sizeof(struct tc3589x), GFP_KERNEL);
    if (!tc3589x)
        return -ENOMEM;

    mutex_init(&tc3589x->lock);

    tc3589x->dev = &i2c->dev;
    tc3589x->i2c = i2c;
    tc3589x->pdata = pdata;
    tc3589x->irq_base = pdata->irq_base;
    tc3589x->num_gpio = id->driver_data;

    i2c_set_clientdata(i2c, tc3589x);

    ret = tc3589x_chip_init(tc3589x);
    if (ret)
        goto out_free;

    ret = tc3589x_irq_init(tc3589x, np);
    if (ret)
        goto out_free;

    ret = request_threaded_irq(tc3589x->i2c->irq, NULL, tc3589x_irq,
                   IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
                   "tc3589x", tc3589x);
    if (ret) {
        dev_err(tc3589x->dev, "failed to request IRQ: %d\n", ret);
        goto out_free;
    }

    ret = tc3589x_device_init(tc3589x);
    if (ret) {
        dev_err(tc3589x->dev, "failed to add child devices\n");
        goto out_freeirq;
    }

    return 0;

out_freeirq:
    free_irq(tc3589x->i2c->irq, tc3589x);
out_free:
    kfree(tc3589x);
    return ret;
}

static int __devexit tc3589x_remove(struct i2c_client *client)
{
    struct tc3589x *tc3589x = i2c_get_clientdata(client);

    mfd_remove_devices(tc3589x->dev);

    free_irq(tc3589x->i2c->irq, tc3589x);

    kfree(tc3589x);

    return 0;
}

#ifdef CONFIG_PM_SLEEP
static int tc3589x_suspend(struct device *dev)
{
    struct tc3589x *tc3589x = dev_get_drvdata(dev);
    struct i2c_client *client = tc3589x->i2c;
    int ret = 0;

    /* put the system to sleep mode */
    if (!device_may_wakeup(&client->dev))
        ret = tc3589x_reg_write(tc3589x, TC3589x_CLKMODE,
                TC3589x_CLKMODE_MODCTL_SLEEP);

    return ret;
}

static int tc3589x_resume(struct device *dev)
{
    struct tc3589x *tc3589x = dev_get_drvdata(dev);
    struct i2c_client *client = tc3589x->i2c;
    int ret = 0;

    /* enable the system into operation */
    if (!device_may_wakeup(&client->dev))
        ret = tc3589x_reg_write(tc3589x, TC3589x_CLKMODE,
                TC3589x_CLKMODE_MODCTL_OPERATION);

    return ret;
}
#endif

static SIMPLE_DEV_PM_OPS(tc3589x_dev_pm_ops, tc3589x_suspend, tc3589x_resume);

static const struct i2c_device_id tc3589x_id[] = {
    { "tc3589x", 24 },
    { }
};
MODULE_DEVICE_TABLE(i2c, tc3589x_id);

static struct i2c_driver tc3589x_driver = {
    .driver.name    = "tc3589x",
    .driver.owner   = THIS_MODULE,
    .driver.pm  = &tc3589x_dev_pm_ops,
    .probe      = tc3589x_probe,
    .remove     = __devexit_p(tc3589x_remove),
    .id_table   = tc3589x_id,
};

static int __init tc3589x_init(void)
{
    return i2c_add_driver(&tc3589x_driver);
}
subsys_initcall(tc3589x_init);

static void __exit tc3589x_exit(void)
{
    i2c_del_driver(&tc3589x_driver);
}
module_exit(tc3589x_exit);

MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("TC3589x MFD core driver");
MODULE_AUTHOR("Hanumath Prasad, Rabin Vincent");