linux-imx

/*

 *  Faraday Technology FTRTC010 driver

 *

 *  Copyright (C) 2009 Janos Laube <janos.dev@gmail.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.

 *

 * Original code for older kernel 2.6.15 are from Stormlinksemi

 * first update from Janos Laube for > 2.6.29 kernels

 *

 * checkpatch fixes and usage of rtc-lib code

 * Hans Ulli Kroll <ulli.kroll@googlemail.com>

 */

​

#include <linux/rtc.h>

#include <linux/io.h>

#include <linux/slab.h>

#include <linux/platform_device.h>

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/mod_devicetable.h>

#include <linux/clk.h>

​

#define DRV_NAME        "rtc-ftrtc010"

​

MODULE_AUTHOR("Hans Ulli Kroll <ulli.kroll@googlemail.com>");

MODULE_DESCRIPTION("RTC driver for Gemini SoC");

MODULE_LICENSE("GPL");

MODULE_ALIAS("platform:" DRV_NAME);

​

struct ftrtc010_rtc {

    struct rtc_device   *rtc_dev;

    void __iomem        *rtc_base;

    int         rtc_irq;

    struct clk      *pclk;

    struct clk      *extclk;

};

​

enum ftrtc010_rtc_offsets {

    FTRTC010_RTC_SECOND     = 0x00,

    FTRTC010_RTC_MINUTE     = 0x04,

    FTRTC010_RTC_HOUR       = 0x08,

    FTRTC010_RTC_DAYS       = 0x0C,

    FTRTC010_RTC_ALARM_SECOND   = 0x10,

    FTRTC010_RTC_ALARM_MINUTE   = 0x14,

    FTRTC010_RTC_ALARM_HOUR     = 0x18,

    FTRTC010_RTC_RECORD     = 0x1C,

    FTRTC010_RTC_CR         = 0x20,

};

​

static irqreturn_t ftrtc010_rtc_interrupt(int irq, void *dev)

{

    return IRQ_HANDLED;

}

​

/*

 * Looks like the RTC in the Gemini SoC is (totaly) broken

 * We can't read/write directly the time from RTC registers.

 * We must do some "offset" calculation to get the real time

 *

 * This FIX works pretty fine and Stormlinksemi aka Cortina-Networks does

 * the same thing, without the rtc-lib.c calls.

 */

​

static int ftrtc010_rtc_read_time(struct device *dev, struct rtc_time *tm)

{

    struct ftrtc010_rtc *rtc = dev_get_drvdata(dev);

​

    u32 days, hour, min, sec, offset;

    timeu64_t time;

​

    sec  = readl(rtc->rtc_base + FTRTC010_RTC_SECOND);

    min  = readl(rtc->rtc_base + FTRTC010_RTC_MINUTE);

    hour = readl(rtc->rtc_base + FTRTC010_RTC_HOUR);

    days = readl(rtc->rtc_base + FTRTC010_RTC_DAYS);

    offset = readl(rtc->rtc_base + FTRTC010_RTC_RECORD);

​

    time = offset + days * 86400 + hour * 3600 + min * 60 + sec;

​

    rtc_time64_to_tm(time, tm);

​

    return 0;

}

​