/*
* 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;
}
static int ftrtc010_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
struct ftrtc010_rtc *rtc = dev_get_drvdata(dev);
u32 sec, min, hour, day, offset;
timeu64_t time;
time = rtc_tm_to_time64(tm);
sec = readl(rtc->rtc_base + FTRTC010_RTC_SECOND);
min = readl(rtc->rtc_base + FTRTC010_RTC_MINUTE);
hour = readl(rtc->rtc_base + FTRTC010_RTC_HOUR);
day = readl(rtc->rtc_base + FTRTC010_RTC_DAYS);
offset = time - (day * 86400 + hour * 3600 + min * 60 + sec);
writel(offset, rtc->rtc_base + FTRTC010_RTC_RECORD);
writel(0x01, rtc->rtc_base + FTRTC010_RTC_CR);
return 0;
}
static const struct rtc_class_ops ftrtc010_rtc_ops = {
.read_time = ftrtc010_rtc_read_time,
.set_time = ftrtc010_rtc_set_time,
};
static int ftrtc010_rtc_probe(struct platform_device *pdev)
{
u32 days, hour, min, sec;
struct ftrtc010_rtc *rtc;
struct device *dev = &pdev->dev;
struct resource *res;
int ret;
rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
if (unlikely(!rtc))
return -ENOMEM;
platform_set_drvdata(pdev, rtc);
rtc->pclk = devm_clk_get(dev, "PCLK");
if (IS_ERR(rtc->pclk)) {
dev_err(dev, "could not get PCLK\n");
} else {
ret = clk_prepare_enable(rtc->pclk);
if (ret) {
dev_err(dev, "failed to enable PCLK\n");
return ret;
}
}
rtc->extclk = devm_clk_get(dev, "EXTCLK");
if (IS_ERR(rtc->extclk)) {
dev_err(dev, "could not get EXTCLK\n");
} else {
ret = clk_prepare_enable(rtc->extclk);
if (ret) {
dev_err(dev, "failed to enable EXTCLK\n");
return ret;
}
}
res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
if (!res)
return -ENODEV;
rtc->rtc_irq = res->start;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res)
return -ENODEV;
rtc->rtc_base = devm_ioremap(dev, res->start,
resource_size(res));
if (!rtc->rtc_base)
return -ENOMEM;
rtc->rtc_dev = devm_rtc_allocate_device(dev);
if (IS_ERR(rtc->rtc_dev))
return PTR_ERR(rtc->rtc_dev);
rtc->rtc_dev->ops = &ftrtc010_rtc_ops;
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);
rtc->rtc_dev->range_min = (u64)days * 86400 + hour * 3600 +
min * 60 + sec;
rtc->rtc_dev->range_max = U32_MAX + rtc->rtc_dev->range_min;
ret = devm_request_irq(dev, rtc->rtc_irq, ftrtc010_rtc_interrupt,
IRQF_SHARED, pdev->name, dev);
if (unlikely(ret))
return ret;
return rtc_register_device(rtc->rtc_dev);
}
static int ftrtc010_rtc_remove(struct platform_device *pdev)
{
struct ftrtc010_rtc *rtc = platform_get_drvdata(pdev);
if (!IS_ERR(rtc->extclk))
clk_disable_unprepare(rtc->extclk);
if (!IS_ERR(rtc->pclk))
clk_disable_unprepare(rtc->pclk);
return 0;
}
static const struct of_device_id ftrtc010_rtc_dt_match[] = {
{ .compatible = "cortina,gemini-rtc" },
{ .compatible = "faraday,ftrtc010" },
{ }
};
MODULE_DEVICE_TABLE(of, ftrtc010_rtc_dt_match);
static struct platform_driver ftrtc010_rtc_driver = {
.driver = {
.name = DRV_NAME,
.of_match_table = ftrtc010_rtc_dt_match,
},
.probe = ftrtc010_rtc_probe,
.remove = ftrtc010_rtc_remove,
};
module_platform_driver_probe(ftrtc010_rtc_driver, ftrtc010_rtc_probe);
