ARM: NUC900: add rtc controller driver support for NUC900

Dear sirs,

This is a RTC driver patch support for NUC910 and NUC920 processors of Winbind/Nuvoton NUC900 ARM series.


Signed-off-by: Wan ZongShun <mcuos.com@gmail.com>

---
 drivers/rtc/Kconfig      |    6 +
 drivers/rtc/Makefile     |    1 +
 drivers/rtc/rtc-nuc900.c |  347 ++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 354 insertions(+), 0 deletions(-)
 create mode 100644 drivers/rtc/rtc-nuc900.c

On Mon, 23 Nov 2009 02:14:56 +0800
Wan ZongShun <mcuos.com@gmail.com> wrote:

> Dear sirs,
> This is a RTC driver patch support for NUC910 and NUC920 processors of Winbind/Nuvoton NUC900 ARM series.
> 
> 
> Signed-off-by: Wan ZongShun <mcuos.com@gmail.com>

 Hello,
 please be sure to follow the checklist at 
 http://groups.google.com/group/rtc-linux/web/checklist

 comments below:
 
> ---
>  drivers/rtc/Kconfig      |    6 +
>  drivers/rtc/Makefile     |    1 +
>  drivers/rtc/rtc-nuc900.c |  347 ++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 354 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/rtc/rtc-nuc900.c
> 
> diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
> index 3c20dae..266ce62 100644
> --- a/drivers/rtc/Kconfig
> +++ b/drivers/rtc/Kconfig
> @@ -573,6 +573,12 @@ config RTC_DRV_AB3100
>  	  Select this to enable the ST-Ericsson AB3100 Mixed Signal IC RTC
>  	  support. This chip contains a battery- and capacitor-backed RTC.
>  
> +config RTC_DRV_NUC900
> +	tristate "NUC910/NUC920 RTC driver"
> +	depends on RTC_CLASS && ARCH_W90X900
> +	help
> +	  If you say yes here you get support for the RTC subsystem of the
> +	  NUC910/NUC920 used in embedded systems.
>  
>  comment "on-CPU RTC drivers"
>  
> diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
> index aa3fbd5..6338887 100644
> --- a/drivers/rtc/Makefile
> +++ b/drivers/rtc/Makefile
> @@ -85,3 +85,4 @@ obj-$(CONFIG_RTC_DRV_VR41XX)	+= rtc-vr41xx.o
>  obj-$(CONFIG_RTC_DRV_WM831X)	+= rtc-wm831x.o
>  obj-$(CONFIG_RTC_DRV_WM8350)	+= rtc-wm8350.o
>  obj-$(CONFIG_RTC_DRV_X1205)	+= rtc-x1205.o
> +obj-$(CONFIG_RTC_DRV_NUC900)	+= rtc-nuc900.o

 alphabeti corder please

> diff --git a/drivers/rtc/rtc-nuc900.c b/drivers/rtc/rtc-nuc900.c
> new file mode 100644
> index 0000000..5059fdc
> --- /dev/null
> +++ b/drivers/rtc/rtc-nuc900.c
> @@ -0,0 +1,347 @@
> +/*
> + * Copyright (c) 2008-2009 Nuvoton technology corporation.
> + *
> + * Wan ZongShun <mcuos.com@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;version 2 of the License.
> + *
> + */
> +
> +#include <linux/module.h>
> +#include <linux/kernel.h>
> +#include <linux/platform_device.h>
> +#include <linux/time.h>
> +#include <linux/rtc.h>
> +#include <linux/delay.h>
> +#include <linux/interrupt.h>
> +#include <linux/ioctl.h>
> +#include <linux/io.h>
> +#include <linux/bcd.h>
> +
> +/* RTC Control Registers */
> +#define REG_RTC_INIR		0x00
> +#define REG_RTC_AER		0x04
> +#define REG_RTC_FCR		0x08
> +#define REG_RTC_TLR		0x0C
> +#define REG_RTC_CLR		0x10
> +#define REG_RTC_TSSR		0x14
> +#define REG_RTC_DWR		0x18
> +#define REG_RTC_TAR		0x1C
> +#define REG_RTC_CAR		0x20
> +#define REG_RTC_LIR		0x24
> +#define REG_RTC_RIER		0x28
> +#define REG_RTC_RIIR		0x2C
> +#define REG_RTC_TTR		0x30
> +
> +#define RTCSET			0x01
> +#define AERRWENB		0x10000
> +#define INIRRESET		0xa5eb1357
> +#define AERPOWERON		0xA965
> +#define AERPOWEROFF		0x0000
> +#define LEAPYEAR		0x0001
> +#define TICKENB			0x80
> +#define TICKINTENB		0x0002
> +#define ALARMINTENB		0x0001
> +
> +struct nuc900_rtc {
> +	int			irq_num;
> +	void __iomem		*rtc_reg;
> +	struct rtc_device	*rtcdev;
> +	spinlock_t		lock;

 why this lock? you need a comment for each spinlock_t .

> +};
> +
> +static const unsigned char days_in_mo[] = {
> +0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31

 no go. check rtc-lib

> +
> +static irqreturn_t nuc900_rtc_interrupt(int irq, void *_rtc)
> +{
> +	struct nuc900_rtc *rtc = _rtc;
> +	unsigned long events = 0, rtc_irq;
> +
> +	rtc_irq = __raw_readl(rtc->rtc_reg + REG_RTC_RIIR);
> +
> +	if (rtc_irq & ALARMINTENB) {
> +		rtc_irq &= ~ALARMINTENB;
> +		__raw_writel(rtc_irq, rtc->rtc_reg + REG_RTC_RIIR);
> +		events |= RTC_AF | RTC_IRQF;
> +	}
> +
> +	if (rtc_irq & TICKINTENB) {
> +		rtc_irq &= ~TICKINTENB;
> +		__raw_writel(rtc_irq, rtc->rtc_reg + REG_RTC_RIIR);
> +		events |= RTC_UF | RTC_IRQF;
> +	}
> +
> +	rtc_update_irq(rtc->rtcdev, 1, events);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static void check_rtc_power(struct nuc900_rtc *nuc900_rtc)
> +{
> +	unsigned int i;
> +	__raw_writel(INIRRESET, nuc900_rtc->rtc_reg + REG_RTC_INIR);
> +
> +	mdelay(10);
> +
> +	__raw_writel(AERPOWERON, nuc900_rtc->rtc_reg + REG_RTC_AER);
> +
> +	for (i = 0; i < 1000000; i++) {
> +		if (__raw_readl(nuc900_rtc->rtc_reg + REG_RTC_AER) & AERRWENB)
> +			break;
> +	}
> +}
> +
> +static void nuc900_rtc_decodetime(unsigned int timereg,
> +				unsigned int calreg, struct rtc_time *tm)
> +{
> +	tm->tm_mday	= bcd2bin(calreg >> 0);
> +	tm->tm_mon	= bcd2bin(calreg >> 8);
> +	tm->tm_year	= bcd2bin(calreg >> 16) + 2000;
> +
> +	tm->tm_sec	= bcd2bin(timereg >> 0);
> +	tm->tm_min	= bcd2bin(timereg >> 8);
> +	tm->tm_hour	= bcd2bin(timereg >> 16);
> +}
> +
> +static void nuc900_rtc_encodetime(struct rtc_time *settm,
> +						struct rtc_time *gettm)
> +{
> +	gettm->tm_mday = bin2bcd((settm->tm_mday) << 0);
> +	gettm->tm_mon  = bin2bcd((settm->tm_mon) << 8);
> +	gettm->tm_year = bin2bcd((settm->tm_year) << 16) - 2000;
> +
> +	gettm->tm_sec  = bin2bcd((settm->tm_sec) << 0);
> +	gettm->tm_min  = bin2bcd((settm->tm_min) << 8);
> +	gettm->tm_hour = bin2bcd((settm->tm_hour) << 16);

 extra parenthesis.
 you are storing bcd values in a struct rtc_time which is
 not meant for that.

> +}
> +
> +static int nuc900_rtc_ioctl(struct device *dev, unsigned int cmd,
> +		unsigned long arg)
> +{
> +	struct nuc900_rtc *rtc = dev_get_drvdata(dev);
> +	int ret = 0;
> +	unsigned int val;
> +	unsigned long flags;
> +
> +	spin_lock_irqsave(&rtc->lock, flags);
> +
> +	val = __raw_readl(rtc->rtc_reg + REG_RTC_RIER);
> +
> +	switch (cmd) {
> +	case RTC_AIE_OFF:		/* alarm off */
> +		val &= (~ALARMINTENB);
> +		break;
> +	case RTC_AIE_ON:		/* alarm on */
> +		val |= ALARMINTENB;
> +		break;
> +	case RTC_UIE_OFF:		/* update off */
> +		val &= (~TICKINTENB);
> +		break;
> +	case RTC_UIE_ON:		/* update on */
> +		val |= TICKINTENB;
> +		break;
> +	default:
> +		ret = -ENOIOCTLCMD;
> +		break;
> +	}
> +
> +	__raw_writel(val, rtc->rtc_reg + REG_RTC_RIER);
> +
> +	spin_unlock_irqrestore(&rtc->lock, flags);
> +
> +	return ret;
> +}

 you don't need ioctl(). check the irq api that other drivers
 use.

> +static int nuc900_rtc_read_time(struct device *dev, struct rtc_time *tm)
> +{
> +	struct nuc900_rtc *rtc = dev_get_drvdata(dev);
> +	unsigned int timeval, clrval;
> +
> +	timeval = __raw_readl(rtc->rtc_reg + REG_RTC_TLR);
> +	clrval	= __raw_readl(rtc->rtc_reg + REG_RTC_CLR);
> +
> +	nuc900_rtc_decodetime(timeval, clrval, tm);
> +
> +	return 0;
> +}
> +
> +static int nuc900_rtc_set_time(struct device *dev, struct rtc_time *tm)
> +{
> +	struct nuc900_rtc *rtc = dev_get_drvdata(dev);
> +	struct rtc_time gettm;
> +	unsigned char leap_yr;
> +	unsigned long val;
> +
> +	nuc900_rtc_encodetime(tm, &gettm);
> +
> +	check_rtc_power(rtc);
> +
> +	leap_yr = __raw_readl(rtc->rtc_reg + REG_RTC_LIR) & LEAPYEAR;
> +
> +	if ((gettm.tm_mon > 12) || (gettm.tm_mday == 0))
> +		return -EINVAL;
> +	if (gettm.tm_mday > (days_in_mo[gettm.tm_mon] +
> +					((gettm.tm_mon == 2) && leap_yr)))
> +		return -EINVAL;
> +	if ((gettm.tm_hour >= 24) || (gettm.tm_min >= 60) ||
> +						(gettm.tm_sec >= 60))
> +		return -EINVAL;
> +
> +	val = gettm.tm_mday | gettm.tm_mon | gettm.tm_year;
> +	__raw_writel(val, rtc->rtc_reg + REG_RTC_CLR);
> +
> +	val = gettm.tm_sec | gettm.tm_min | gettm.tm_hour;
> +	__raw_writel(val, rtc->rtc_reg + REG_RTC_TLR);
> +
> +	return 0;
> +}
> +
> +static int nuc900_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
> +{
> +	struct nuc900_rtc *rtc = dev_get_drvdata(dev);
> +	unsigned int timeval, carval;
> +
> +	timeval = __raw_readl(rtc->rtc_reg + REG_RTC_TAR);
> +	carval	= __raw_readl(rtc->rtc_reg + REG_RTC_CAR);
> +
> +	nuc900_rtc_decodetime(timeval, carval, &alrm->time);
> +
> +	return 0;
> +}
> +
> +static int nuc900_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
> +{
> +	struct nuc900_rtc *rtc = dev_get_drvdata(dev);
> +	struct rtc_time tm;
> +	unsigned long val;
> +
> +	nuc900_rtc_encodetime(&alrm->time, &tm);
> +
> +	check_rtc_power(rtc);
> +
> +	val = tm.tm_mday | tm.tm_mon | tm.tm_year;
> +	__raw_writel(val, rtc->rtc_reg + REG_RTC_CAR);
> +
> +	val = tm.tm_sec | tm.tm_min | tm.tm_hour;
> +	__raw_writel(val, rtc->rtc_reg + REG_RTC_TAR);
> +
> +	if (alrm->enabled) {
> +		__raw_writel(__raw_readl(rtc->rtc_reg + REG_RTC_RIER)|
> +			(ALARMINTENB), rtc->rtc_reg + REG_RTC_RIER);
> +	}
> +
> +	return 0;
> +}
> +
> +static struct rtc_class_ops nuc900_rtc_ops = {
> +	.ioctl = nuc900_rtc_ioctl,
> +	.read_time = nuc900_rtc_read_time,
> +	.set_time = nuc900_rtc_set_time,
> +	.read_alarm = nuc900_rtc_read_alarm,
> +	.set_alarm = nuc900_rtc_set_alarm,
> +};
> +
> +static int __devinit nuc900_rtc_probe(struct platform_device *pdev)
> +{
> +	struct resource *res;
> +	struct nuc900_rtc *nuc900_rtc;
> +	int err;
> +
> +	nuc900_rtc = kzalloc(sizeof(struct nuc900_rtc), GFP_KERNEL);
> +	if (!nuc900_rtc) {
> +		err = -ENOMEM;
> +		goto fail1;
> +	}
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!res) {
> +		err = -ENXIO;
> +		goto fail1;
> +	}
> +
> +	if (!request_mem_region(res->start, resource_size(res),
> +				pdev->name)) {
> +		err = -EBUSY;
> +		goto fail1;
> +	}
> +
> +	nuc900_rtc->rtc_reg = ioremap(res->start, resource_size(res));
> +	if (!nuc900_rtc->rtc_reg) {
> +		err = -ENOMEM;
> +		goto fail2;
> +	}
> +
> +	nuc900_rtc->irq_num = platform_get_irq(pdev, 0);
> +	if (request_irq(nuc900_rtc->irq_num, nuc900_rtc_interrupt,
> +			IRQF_DISABLED, "nuc900rtc", nuc900_rtc)) {
> +		err = -EBUSY;
> +		goto fail3;
> +	}
> +
> +	nuc900_rtc->rtcdev = rtc_device_register(pdev->name, &pdev->dev,
> +						&nuc900_rtc_ops, THIS_MODULE);
> +	if (IS_ERR(nuc900_rtc->rtcdev)) {
> +		err = PTR_ERR(nuc900_rtc->rtcdev);
> +		goto fail4;
> +	}
> +	platform_set_drvdata(pdev, nuc900_rtc->rtcdev);
> +	spin_lock_init(&nuc900_rtc->lock);
> +
> +	return 0;
> +
> +fail4:	free_irq(nuc900_rtc->irq_num, nuc900_rtc);
> +fail3:	iounmap(nuc900_rtc->rtc_reg);
> +fail2:	release_mem_region(res->start, resource_size(res));
> +fail1:	kfree(nuc900_rtc);
> +	return err;
> +}
> +
> +static int __devexit nuc900_rtc_remove(struct platform_device *pdev)
> +{
> +	struct nuc900_rtc *nuc900_rtc = platform_get_drvdata(pdev);
> +	struct resource *res;
> +
> +	free_irq(nuc900_rtc->irq_num, nuc900_rtc);
> +	iounmap(nuc900_rtc->rtc_reg);
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	release_mem_region(res->start, resource_size(res));
> +
> +	rtc_device_unregister(nuc900_rtc->rtcdev);
> +	kfree(nuc900_rtc);
> +
> +	platform_set_drvdata(pdev, NULL);
> +
> +	return 0;
> +}

 rtc_device_unregister should be called first.

> +
> +static struct platform_driver nuc900_rtc_driver = {
> +	.probe		= nuc900_rtc_probe,
> +	.remove		= __devexit_p(nuc900_rtc_remove),
> +	.driver		= {
> +		.name	= "nuc900-rtc",
> +		.owner	= THIS_MODULE,
> +	},
> +};
> +
> +static int __init nuc900_rtc_init(void)
> +{
> +	return platform_driver_register(&nuc900_rtc_driver);
> +}

 I guess you can use platform_device_probe. 

> +
> +static void __exit nuc900_rtc_exit(void)
> +{
> +	platform_driver_unregister(&nuc900_rtc_driver);
> +}
> +
> +module_init(nuc900_rtc_init);
> +module_exit(nuc900_rtc_exit);
> +
> +MODULE_AUTHOR("Wan ZongShun <mcuos.com@gmail.com>");
> +MODULE_DESCRIPTION("nuc910/nuc920 RTC driver");
> +MODULE_LICENSE("GPL");
> +MODULE_ALIAS("platform:nuc900-rtc");
> -- 
> 1.5.6.3