pm8921-core.c

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/*
 * Copyright (c) 2011, Code Aurora Forum. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 and
 * only version 2 as published by the Free Software Foundation.
 *
 * 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.
 */

#define pr_fmt(fmt) "%s: " fmt, __func__

#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/msm_ssbi.h>
#include <linux/mfd/core.h>
#include <linux/mfd/pm8xxx/pm8921.h>
#include <linux/mfd/pm8xxx/core.h>

#define REG_HWREV       0x002  /* PMIC4 revision */
#define REG_HWREV_2     0x0E8  /* PMIC4 revision 2 */

struct pm8921 {
    struct device           *dev;
    struct pm_irq_chip      *irq_chip;
};

static int pm8921_readb(const struct device *dev, u16 addr, u8 *val)
{
    const struct pm8xxx_drvdata *pm8921_drvdata = dev_get_drvdata(dev);
    const struct pm8921 *pmic = pm8921_drvdata->pm_chip_data;

    return msm_ssbi_read(pmic->dev->parent, addr, val, 1);
}

static int pm8921_writeb(const struct device *dev, u16 addr, u8 val)
{
    const struct pm8xxx_drvdata *pm8921_drvdata = dev_get_drvdata(dev);
    const struct pm8921 *pmic = pm8921_drvdata->pm_chip_data;

    return msm_ssbi_write(pmic->dev->parent, addr, &val, 1);
}

static int pm8921_read_buf(const struct device *dev, u16 addr, u8 *buf,
                                    int cnt)
{
    const struct pm8xxx_drvdata *pm8921_drvdata = dev_get_drvdata(dev);
    const struct pm8921 *pmic = pm8921_drvdata->pm_chip_data;

    return msm_ssbi_read(pmic->dev->parent, addr, buf, cnt);
}

static int pm8921_write_buf(const struct device *dev, u16 addr, u8 *buf,
                                    int cnt)
{
    const struct pm8xxx_drvdata *pm8921_drvdata = dev_get_drvdata(dev);
    const struct pm8921 *pmic = pm8921_drvdata->pm_chip_data;

    return msm_ssbi_write(pmic->dev->parent, addr, buf, cnt);
}

static int pm8921_read_irq_stat(const struct device *dev, int irq)
{
    const struct pm8xxx_drvdata *pm8921_drvdata = dev_get_drvdata(dev);
    const struct pm8921 *pmic = pm8921_drvdata->pm_chip_data;

    return pm8xxx_get_irq_stat(pmic->irq_chip, irq);
}

static struct pm8xxx_drvdata pm8921_drvdata = {
    .pmic_readb     = pm8921_readb,
    .pmic_writeb        = pm8921_writeb,
    .pmic_read_buf      = pm8921_read_buf,
    .pmic_write_buf     = pm8921_write_buf,
    .pmic_read_irq_stat = pm8921_read_irq_stat,
};

static int __devinit pm8921_add_subdevices(const struct pm8921_platform_data
                       *pdata,
                       struct pm8921 *pmic,
                       u32 rev)
{
    int ret = 0, irq_base = 0;
    struct pm_irq_chip *irq_chip;

    if (pdata->irq_pdata) {
        pdata->irq_pdata->irq_cdata.nirqs = PM8921_NR_IRQS;
        pdata->irq_pdata->irq_cdata.rev = rev;
        irq_base = pdata->irq_pdata->irq_base;
        irq_chip = pm8xxx_irq_init(pmic->dev, pdata->irq_pdata);

        if (IS_ERR(irq_chip)) {
            pr_err("Failed to init interrupts ret=%ld\n",
                    PTR_ERR(irq_chip));
            return PTR_ERR(irq_chip);
        }
        pmic->irq_chip = irq_chip;
    }
    return ret;
}

static int __devinit pm8921_probe(struct platform_device *pdev)
{
    const struct pm8921_platform_data *pdata = pdev->dev.platform_data;
    struct pm8921 *pmic;
    int rc;
    u8 val;
    u32 rev;

    if (!pdata) {
        pr_err("missing platform data\n");
        return -EINVAL;
    }

    pmic = kzalloc(sizeof(struct pm8921), GFP_KERNEL);
    if (!pmic) {
        pr_err("Cannot alloc pm8921 struct\n");
        return -ENOMEM;
    }

    /* Read PMIC chip revision */
    rc = msm_ssbi_read(pdev->dev.parent, REG_HWREV, &val, sizeof(val));
    if (rc) {
        pr_err("Failed to read hw rev reg %d:rc=%d\n", REG_HWREV, rc);
        goto err_read_rev;
    }
    pr_info("PMIC revision 1: %02X\n", val);
    rev = val;

    /* Read PMIC chip revision 2 */
    rc = msm_ssbi_read(pdev->dev.parent, REG_HWREV_2, &val, sizeof(val));
    if (rc) {
        pr_err("Failed to read hw rev 2 reg %d:rc=%d\n",
            REG_HWREV_2, rc);
        goto err_read_rev;
    }
    pr_info("PMIC revision 2: %02X\n", val);
    rev |= val << BITS_PER_BYTE;

    pmic->dev = &pdev->dev;
    pm8921_drvdata.pm_chip_data = pmic;
    platform_set_drvdata(pdev, &pm8921_drvdata);

    rc = pm8921_add_subdevices(pdata, pmic, rev);
    if (rc) {
        pr_err("Cannot add subdevices rc=%d\n", rc);
        goto err;
    }

    /* gpio might not work if no irq device is found */
    WARN_ON(pmic->irq_chip == NULL);

    return 0;

err:
    mfd_remove_devices(pmic->dev);
    platform_set_drvdata(pdev, NULL);
err_read_rev:
    kfree(pmic);
    return rc;
}

static int __devexit pm8921_remove(struct platform_device *pdev)
{
    struct pm8xxx_drvdata *drvdata;
    struct pm8921 *pmic = NULL;

    drvdata = platform_get_drvdata(pdev);
    if (drvdata)
        pmic = drvdata->pm_chip_data;
    if (pmic)
        mfd_remove_devices(pmic->dev);
    if (pmic->irq_chip) {
        pm8xxx_irq_exit(pmic->irq_chip);
        pmic->irq_chip = NULL;
    }
    platform_set_drvdata(pdev, NULL);
    kfree(pmic);

    return 0;
}

static struct platform_driver pm8921_driver = {
    .probe      = pm8921_probe,
    .remove     = __devexit_p(pm8921_remove),
    .driver     = {
        .name   = "pm8921-core",
        .owner  = THIS_MODULE,
    },
};

static int __init pm8921_init(void)
{
    return platform_driver_register(&pm8921_driver);
}
subsys_initcall(pm8921_init);

static void __exit pm8921_exit(void)
{
    platform_driver_unregister(&pm8921_driver);
}
module_exit(pm8921_exit);

MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("PMIC 8921 core driver");
MODULE_VERSION("1.0");
MODULE_ALIAS("platform:pm8921-core");