linux-imx

/*

 * Copyright (C) ST-Ericsson SA 2010

 *

 * License terms: GNU General Public License (GPL) version 2

 * Author: Virupax Sadashivpetimath <virupax.sadashivpetimath@stericsson.com>

 *

 * RTC clock driver for the RTC part of the AB8500 Power management chip.

 * Based on RTC clock driver for the AB3100 Analog Baseband Chip by

 * Linus Walleij <linus.walleij@stericsson.com>

 */

​

#include <linux/module.h>

#include <linux/kernel.h>

#include <linux/init.h>

#include <linux/platform_device.h>

#include <linux/rtc.h>

#include <linux/mfd/abx500.h>

#include <linux/mfd/abx500/ab8500.h>

#include <linux/delay.h>

#include <linux/of.h>

#include <linux/pm_wakeirq.h>

​

#define AB8500_RTC_SOFF_STAT_REG    0x00

#define AB8500_RTC_CC_CONF_REG      0x01

#define AB8500_RTC_READ_REQ_REG     0x02

#define AB8500_RTC_WATCH_TSECMID_REG    0x03

#define AB8500_RTC_WATCH_TSECHI_REG 0x04

#define AB8500_RTC_WATCH_TMIN_LOW_REG   0x05

#define AB8500_RTC_WATCH_TMIN_MID_REG   0x06

#define AB8500_RTC_WATCH_TMIN_HI_REG    0x07

#define AB8500_RTC_ALRM_MIN_LOW_REG 0x08

#define AB8500_RTC_ALRM_MIN_MID_REG 0x09

#define AB8500_RTC_ALRM_MIN_HI_REG  0x0A

#define AB8500_RTC_STAT_REG     0x0B

#define AB8500_RTC_BKUP_CHG_REG     0x0C

#define AB8500_RTC_FORCE_BKUP_REG   0x0D

#define AB8500_RTC_CALIB_REG        0x0E

#define AB8500_RTC_SWITCH_STAT_REG  0x0F

​

/* RtcReadRequest bits */

#define RTC_READ_REQUEST        0x01

#define RTC_WRITE_REQUEST       0x02

​

/* RtcCtrl bits */

#define RTC_ALARM_ENA           0x04

#define RTC_STATUS_DATA         0x01

​

#define COUNTS_PER_SEC          (0xF000 / 60)

​

static const u8 ab8500_rtc_time_regs[] = {

    AB8500_RTC_WATCH_TMIN_HI_REG, AB8500_RTC_WATCH_TMIN_MID_REG,

    AB8500_RTC_WATCH_TMIN_LOW_REG, AB8500_RTC_WATCH_TSECHI_REG,

    AB8500_RTC_WATCH_TSECMID_REG

};

​

static const u8 ab8500_rtc_alarm_regs[] = {

    AB8500_RTC_ALRM_MIN_HI_REG, AB8500_RTC_ALRM_MIN_MID_REG,

    AB8500_RTC_ALRM_MIN_LOW_REG

};

​

static int ab8500_rtc_read_time(struct device *dev, struct rtc_time *tm)

{

    unsigned long timeout = jiffies + HZ;

    int retval, i;

    unsigned long mins, secs;

    unsigned char buf[ARRAY_SIZE(ab8500_rtc_time_regs)];

    u8 value;

​

    /* Request a data read */

    retval = abx500_set_register_interruptible(dev,

        AB8500_RTC, AB8500_RTC_READ_REQ_REG, RTC_READ_REQUEST);

    if (retval < 0)

        return retval;

​

    /* Wait for some cycles after enabling the rtc read in ab8500 */

    while (time_before(jiffies, timeout)) {

        retval = abx500_get_register_interruptible(dev,

            AB8500_RTC, AB8500_RTC_READ_REQ_REG, &value);

        if (retval < 0)

            return retval;

​

        if (!(value & RTC_READ_REQUEST))

            break;

​

        usleep_range(1000, 5000);

    }

​

    /* Read the Watchtime registers */

    for (i = 0; i < ARRAY_SIZE(ab8500_rtc_time_regs); i++) {

        retval = abx500_get_register_interruptible(dev,

            AB8500_RTC, ab8500_rtc_time_regs[i], &value);

        if (retval < 0)