Commit df17f631 authored by dmitry pervushin's avatar dmitry pervushin Committed by Linus Torvalds
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rtc: add Freescale stmp37xx/378x driver 



Add support for RTC on the Freescale STMP37xx/378x platform.

Signed-off-by: default avatardmitry pervushin <dpervushin@embeddedalley.com>
Signed-off-by: default avatarAlessandro Zummo <a.zummo@towertech.it>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 6bff5fb8

drivers/rtc/Kconfig

+10 −0
Original line number Diff line number Diff line
@@ -810,4 +810,14 @@ config RTC_DRV_COH901331 
	  will be called "rtc-coh901331".





config RTC_DRV_STMP

	tristate "Freescale STMP3xxx RTC"

	depends on ARCH_STMP3XXX

	help

	  If you say yes here you will get support for the onboard

	  STMP3xxx RTC.



	  This driver can also be built as a module. If so, the module

	  will be called rtc-stmp3xxx.



endif # RTC_CLASS

drivers/rtc/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -83,3 +83,4 @@ obj-$(CONFIG_RTC_DRV_X1205) += rtc-x1205.o 
obj-$(CONFIG_RTC_DRV_PCF50633)	+= rtc-pcf50633.o

obj-$(CONFIG_RTC_DRV_PS3)	+= rtc-ps3.o

obj-$(CONFIG_RTC_DRV_COH901331)	+= rtc-coh901331.o

obj-$(CONFIG_RTC_DRV_STMP)	+= rtc-stmp3xxx.o

drivers/rtc/rtc-stmp3xxx.c

0 → 100644
+304 −0
Original line number Diff line number Diff line 
/*

 * Freescale STMP37XX/STMP378X Real Time Clock driver

 *

 * Copyright (c) 2007 Sigmatel, Inc.

 * Peter Hartley, <peter.hartley@sigmatel.com>

 *

 * Copyright 2008 Freescale Semiconductor, Inc. All Rights Reserved.

 * Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved.

 */



/*

 * The code contained herein is licensed under the GNU General Public

 * License. You may obtain a copy of the GNU General Public License

 * Version 2 or later at the following locations:

 *

 * http://www.opensource.org/licenses/gpl-license.html

 * http://www.gnu.org/copyleft/gpl.html

 */

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/init.h>

#include <linux/platform_device.h>

#include <linux/interrupt.h>

#include <linux/rtc.h>



#include <mach/platform.h>

#include <mach/stmp3xxx.h>

#include <mach/regs-rtc.h>



struct stmp3xxx_rtc_data {

	struct rtc_device *rtc;

	unsigned irq_count;

	void __iomem *io;

	int irq_alarm, irq_1msec;

};



static void stmp3xxx_wait_time(struct stmp3xxx_rtc_data *rtc_data)

{

	/*

	 * The datasheet doesn't say which way round the

	 * NEW_REGS/STALE_REGS bitfields go. In fact it's 0x1=P0,

	 * 0x2=P1, .., 0x20=P5, 0x40=ALARM, 0x80=SECONDS

	 */

	while (__raw_readl(rtc_data->io + HW_RTC_STAT) &

			BF(0x80, RTC_STAT_STALE_REGS))

		cpu_relax();

}



/* Time read/write */

static int stmp3xxx_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)

{

	struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);



	stmp3xxx_wait_time(rtc_data);

	rtc_time_to_tm(__raw_readl(rtc_data->io + HW_RTC_SECONDS), rtc_tm);

	return 0;

}



static int stmp3xxx_rtc_set_mmss(struct device *dev, unsigned long t)

{

	struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);



	__raw_writel(t, rtc_data->io + HW_RTC_SECONDS);

	stmp3xxx_wait_time(rtc_data);

	return 0;

}



/* interrupt(s) handler */

static irqreturn_t stmp3xxx_rtc_interrupt(int irq, void *dev_id)

{

	struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev_id);

	u32 status;

	u32 events = 0;



	status = __raw_readl(rtc_data->io + HW_RTC_CTRL) &

			(BM_RTC_CTRL_ALARM_IRQ | BM_RTC_CTRL_ONEMSEC_IRQ);



	if (status & BM_RTC_CTRL_ALARM_IRQ) {

		stmp3xxx_clearl(BM_RTC_CTRL_ALARM_IRQ,

				rtc_data->io + HW_RTC_CTRL);

		events |= RTC_AF | RTC_IRQF;

	}



	if (status & BM_RTC_CTRL_ONEMSEC_IRQ) {

		stmp3xxx_clearl(BM_RTC_CTRL_ONEMSEC_IRQ,

				rtc_data->io + HW_RTC_CTRL);

		if (++rtc_data->irq_count % 1000 == 0) {

			events |= RTC_UF | RTC_IRQF;

			rtc_data->irq_count = 0;

		}

	}



	if (events)

		rtc_update_irq(rtc_data->rtc, 1, events);



	return IRQ_HANDLED;

}



static int stmp3xxx_alarm_irq_enable(struct device *dev, unsigned int enabled)

{

	struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);

	void __iomem *p = rtc_data->io + HW_RTC_PERSISTENT0,

		     *ctl = rtc_data->io + HW_RTC_CTRL;



	if (enabled) {

		stmp3xxx_setl(BM_RTC_PERSISTENT0_ALARM_EN |

			      BM_RTC_PERSISTENT0_ALARM_WAKE_EN, p);

		stmp3xxx_setl(BM_RTC_CTRL_ALARM_IRQ_EN, ctl);

	} else {

		stmp3xxx_clearl(BM_RTC_PERSISTENT0_ALARM_EN |

			      BM_RTC_PERSISTENT0_ALARM_WAKE_EN, p);

		stmp3xxx_clearl(BM_RTC_CTRL_ALARM_IRQ_EN, ctl);

	}

	return 0;

}



static int stmp3xxx_update_irq_enable(struct device *dev, unsigned int enabled)

{

	struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);



	if (enabled)

		stmp3xxx_setl(BM_RTC_CTRL_ONEMSEC_IRQ_EN,

				rtc_data->io + HW_RTC_CTRL);

	else

		stmp3xxx_clearl(BM_RTC_CTRL_ONEMSEC_IRQ_EN,

				rtc_data->io + HW_RTC_CTRL);

	return 0;

}



static int stmp3xxx_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)

{

	struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);



	rtc_time_to_tm(__raw_readl(rtc_data->io + HW_RTC_ALARM), &alm->time);

	return 0;

}



static int stmp3xxx_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)

{

	unsigned long t;

	struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);



	rtc_tm_to_time(&alm->time, &t);

	__raw_writel(t, rtc_data->io + HW_RTC_ALARM);

	return 0;

}



static struct rtc_class_ops stmp3xxx_rtc_ops = {

	.alarm_irq_enable =

			  stmp3xxx_alarm_irq_enable,

	.update_irq_enable =

			  stmp3xxx_update_irq_enable,

	.read_time	= stmp3xxx_rtc_gettime,

	.set_mmss	= stmp3xxx_rtc_set_mmss,

	.read_alarm	= stmp3xxx_rtc_read_alarm,

	.set_alarm	= stmp3xxx_rtc_set_alarm,

};



static int stmp3xxx_rtc_remove(struct platform_device *pdev)

{

	struct stmp3xxx_rtc_data *rtc_data = platform_get_drvdata(pdev);



	if (!rtc_data)

		return 0;



	stmp3xxx_clearl(BM_RTC_CTRL_ONEMSEC_IRQ_EN | BM_RTC_CTRL_ALARM_IRQ_EN,

			rtc_data->io + HW_RTC_CTRL);

	free_irq(rtc_data->irq_alarm, &pdev->dev);

	free_irq(rtc_data->irq_1msec, &pdev->dev);

	rtc_device_unregister(rtc_data->rtc);

	iounmap(rtc_data->io);

	kfree(rtc_data);



	return 0;

}



static int stmp3xxx_rtc_probe(struct platform_device *pdev)

{

	struct stmp3xxx_rtc_data *rtc_data;

	struct resource *r;

	int err;



	rtc_data = kzalloc(sizeof *rtc_data, GFP_KERNEL);

	if (!rtc_data)

		return -ENOMEM;



	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);

	if (!r) {

		dev_err(&pdev->dev, "failed to get resource\n");

		err = -ENXIO;

		goto out_free;

	}



	rtc_data->io = ioremap(r->start, resource_size(r));

	if (!rtc_data->io) {

		dev_err(&pdev->dev, "ioremap failed\n");

		err = -EIO;

		goto out_free;

	}



	rtc_data->irq_alarm = platform_get_irq(pdev, 0);

	rtc_data->irq_1msec = platform_get_irq(pdev, 1);



	if (!(__raw_readl(HW_RTC_STAT + rtc_data->io) &

			BM_RTC_STAT_RTC_PRESENT)) {

		dev_err(&pdev->dev, "no device onboard\n");

		err = -ENODEV;

		goto out_remap;

	}



	stmp3xxx_reset_block(rtc_data->io, true);

	stmp3xxx_clearl(BM_RTC_PERSISTENT0_ALARM_EN |

			BM_RTC_PERSISTENT0_ALARM_WAKE_EN |

			BM_RTC_PERSISTENT0_ALARM_WAKE,

			rtc_data->io + HW_RTC_PERSISTENT0);

	rtc_data->rtc = rtc_device_register(pdev->name, &pdev->dev,

				&stmp3xxx_rtc_ops, THIS_MODULE);

	if (IS_ERR(rtc_data->rtc)) {

		err = PTR_ERR(rtc_data->rtc);

		goto out_remap;

	}



	rtc_data->irq_count = 0;

	err = request_irq(rtc_data->irq_alarm, stmp3xxx_rtc_interrupt,

			IRQF_DISABLED, "RTC alarm", &pdev->dev);

	if (err) {

		dev_err(&pdev->dev, "Cannot claim IRQ%d\n",

			rtc_data->irq_alarm);

		goto out_irq_alarm;

	}

	err = request_irq(rtc_data->irq_1msec, stmp3xxx_rtc_interrupt,

			IRQF_DISABLED, "RTC tick", &pdev->dev);

	if (err) {

		dev_err(&pdev->dev, "Cannot claim IRQ%d\n",

			rtc_data->irq_1msec);

		goto out_irq1;

	}



	platform_set_drvdata(pdev, rtc_data);



	return 0;



out_irq1:

	free_irq(rtc_data->irq_alarm, &pdev->dev);

out_irq_alarm:

	stmp3xxx_clearl(BM_RTC_CTRL_ONEMSEC_IRQ_EN | BM_RTC_CTRL_ALARM_IRQ_EN,

			rtc_data->io + HW_RTC_CTRL);

	rtc_device_unregister(rtc_data->rtc);

out_remap:

	iounmap(rtc_data->io);

out_free:

	kfree(rtc_data);

	return err;

}



#ifdef CONFIG_PM

static int stmp3xxx_rtc_suspend(struct platform_device *dev, pm_message_t state)

{

	return 0;

}



static int stmp3xxx_rtc_resume(struct platform_device *dev)

{

	struct stmp3xxx_rtc_data *rtc_data = platform_get_drvdata(dev);



	stmp3xxx_reset_block(rtc_data->io, true);

	stmp3xxx_clearl(BM_RTC_PERSISTENT0_ALARM_EN |

			BM_RTC_PERSISTENT0_ALARM_WAKE_EN |

			BM_RTC_PERSISTENT0_ALARM_WAKE,

			rtc_data->io + HW_RTC_PERSISTENT0);

	return 0;

}

#else

#define stmp3xxx_rtc_suspend	NULL

#define stmp3xxx_rtc_resume	NULL

#endif



static struct platform_driver stmp3xxx_rtcdrv = {

	.probe		= stmp3xxx_rtc_probe,

	.remove		= stmp3xxx_rtc_remove,

	.suspend	= stmp3xxx_rtc_suspend,

	.resume		= stmp3xxx_rtc_resume,

	.driver		= {

		.name	= "stmp3xxx-rtc",

		.owner	= THIS_MODULE,

	},

};



static int __init stmp3xxx_rtc_init(void)

{

	return platform_driver_register(&stmp3xxx_rtcdrv);

}



static void __exit stmp3xxx_rtc_exit(void)

{

	platform_driver_unregister(&stmp3xxx_rtcdrv);

}



module_init(stmp3xxx_rtc_init);

module_exit(stmp3xxx_rtc_exit);



MODULE_DESCRIPTION("STMP3xxx RTC Driver");

MODULE_AUTHOR("dmitry pervushin <dpervushin@embeddedalley.com>");

MODULE_LICENSE("GPL");