lkml.org 
[lkml]   [2010]   [Nov]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 5/6 v2] rtc: Add support for the RTC in VIA VT8500 and compatibles
    Date
    This adds a driver for the RTC devices in VIA and WonderMedia
    Systems-on-Chip. Alarm, 1Hz interrupts, reading and setting time
    are supported.

    Signed-off-by: Alexey Charkov <alchark@gmail.com>
    ---

    Please review and (if appropriate) commit to a relevant git tree for
    further integration in 2.6.38.

    Compared to the previous submission, this code just contains a rebase
    against the latest changes introduced in 2.6.37 merge window.

    Relevant platform definitions are introduced by PATCH 1/6 in this series,
    so one would need that to make use of this code.

    Due credits go to the community for providing feedback, advice and
    testing.

    drivers/rtc/Kconfig | 7 +
    drivers/rtc/Makefile | 1 +
    drivers/rtc/rtc-vt8500.c | 363 ++++++++++++++++++++++++++++++++++++++++++++++
    3 files changed, 371 insertions(+), 0 deletions(-)
    create mode 100644 drivers/rtc/rtc-vt8500.c

    diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
    index 2883428..27ed129 100644
    --- a/drivers/rtc/Kconfig
    +++ b/drivers/rtc/Kconfig
    @@ -865,6 +865,13 @@ config RTC_DRV_PXA
    This RTC driver uses PXA RTC registers available since pxa27x
    series (RDxR, RYxR) instead of legacy RCNR, RTAR.

    +config RTC_DRV_VT8500
    + tristate "VIA/WonderMedia 85xx SoC RTC"
    + depends on ARCH_VT8500
    + help
    + If you say Y here you will get access to the real time clock
    + built into your VIA VT8500 SoC or its relatives.
    +

    config RTC_DRV_SUN4V
    bool "SUN4V Hypervisor RTC"
    diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
    index 4c2832d..1a354e1 100644
    --- a/drivers/rtc/Makefile
    +++ b/drivers/rtc/Makefile
    @@ -97,6 +97,7 @@ obj-$(CONFIG_RTC_DRV_TWL4030) += rtc-twl.o
    obj-$(CONFIG_RTC_DRV_TX4939) += rtc-tx4939.o
    obj-$(CONFIG_RTC_DRV_V3020) += rtc-v3020.o
    obj-$(CONFIG_RTC_DRV_VR41XX) += rtc-vr41xx.o
    +obj-$(CONFIG_RTC_DRV_VT8500) += rtc-vt8500.o
    obj-$(CONFIG_RTC_DRV_WM831X) += rtc-wm831x.o
    obj-$(CONFIG_RTC_DRV_WM8350) += rtc-wm8350.o
    obj-$(CONFIG_RTC_DRV_X1205) += rtc-x1205.o
    diff --git a/drivers/rtc/rtc-vt8500.c b/drivers/rtc/rtc-vt8500.c
    new file mode 100644
    index 0000000..7260c95
    --- /dev/null
    +++ b/drivers/rtc/rtc-vt8500.c
    @@ -0,0 +1,363 @@
    +/*
    + * drivers/rtc/rtc-vt8500.c
    + *
    + * Copyright (C) 2010 Alexey Charkov <alchark@gmail.com>
    + *
    + * Based on rtc-pxa.c
    + *
    + * This software is licensed under the terms of the GNU General Public
    + * License version 2, as published by the Free Software Foundation, and
    + * may be copied, distributed, and modified under those terms.
    + *
    + * 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.
    + */
    +
    +#include <linux/module.h>
    +#include <linux/rtc.h>
    +#include <linux/init.h>
    +#include <linux/interrupt.h>
    +#include <linux/io.h>
    +#include <linux/bcd.h>
    +#include <linux/platform_device.h>
    +#include <linux/slab.h>
    +
    +/*
    + * Register definitions
    + */
    +#define VT8500_RTC_TS 0x00 /* Time set */
    +#define VT8500_RTC_DS 0x04 /* Date set */
    +#define VT8500_RTC_AS 0x08 /* Alarm set */
    +#define VT8500_RTC_CR 0x0c /* Control */
    +#define VT8500_RTC_TR 0x10 /* Time read */
    +#define VT8500_RTC_DR 0x14 /* Date read */
    +#define VT8500_RTC_WS 0x18 /* Write status */
    +#define VT8500_RTC_CL 0x20 /* Calibration */
    +#define VT8500_RTC_IS 0x24 /* Interrupt status */
    +#define VT8500_RTC_ST 0x28 /* Status */
    +
    +#define INVALID_TIME_BIT (1 << 31)
    +
    +#define DATE_CENTURY_S 19
    +#define DATE_YEAR_S 11
    +#define DATE_YEAR_MASK (0xff << DATE_YEAR_S)
    +#define DATE_MONTH_S 6
    +#define DATE_MONTH_MASK (0x1f << DATE_MONTH_S)
    +#define DATE_DAY_MASK 0x3f
    +
    +#define TIME_DOW_S 20
    +#define TIME_DOW_MASK (0x07 << TIME_DOW_S)
    +#define TIME_HOUR_S 14
    +#define TIME_HOUR_MASK (0x3f << TIME_HOUR_S)
    +#define TIME_MIN_S 7
    +#define TIME_MIN_MASK (0x7f << TIME_MIN_S)
    +#define TIME_SEC_MASK 0x7f
    +
    +#define ALARM_DAY_S 20
    +#define ALARM_DAY_MASK (0x3f << ALARM_DAY_S)
    +
    +#define ALARM_DAY_BIT (1 << 29)
    +#define ALARM_HOUR_BIT (1 << 28)
    +#define ALARM_MIN_BIT (1 << 27)
    +#define ALARM_SEC_BIT (1 << 26)
    +
    +#define ALARM_ENABLE_MASK (ALARM_DAY_BIT \
    + | ALARM_HOUR_BIT \
    + | ALARM_MIN_BIT \
    + | ALARM_SEC_BIT)
    +
    +struct vt8500_rtc {
    + void __iomem *regbase;
    + int irq_alarm;
    + int irq_hz;
    + struct rtc_device *rtc;
    + spinlock_t lock; /* Protects this structure */
    + struct rtc_time rtc_alarm;
    +};
    +
    +static irqreturn_t vt8500_rtc_irq(int irq, void *dev_id)
    +{
    + struct platform_device *pdev = to_platform_device(dev_id);
    + struct vt8500_rtc *vt8500_rtc = platform_get_drvdata(pdev);
    + u32 isr;
    + unsigned long events = 0;
    +
    + spin_lock(&vt8500_rtc->lock);
    +
    + /* clear interrupt sources */
    + isr = readl(vt8500_rtc->regbase + VT8500_RTC_IS);
    + writel(isr, vt8500_rtc->regbase + VT8500_RTC_IS);
    +
    + if (isr & 1)
    + events |= RTC_AF | RTC_IRQF;
    +
    + /* Only second/minute interrupts are supported */
    + if (isr & 2)
    + events |= RTC_UF | RTC_IRQF;
    +
    + rtc_update_irq(vt8500_rtc->rtc, 1, events);
    +
    + spin_unlock(&vt8500_rtc->lock);
    + return IRQ_HANDLED;
    +}
    +
    +static int vt8500_rtc_open(struct device *dev)
    +{
    + struct vt8500_rtc *vt8500_rtc = dev_get_drvdata(dev);
    + int ret;
    +
    + ret = request_irq(vt8500_rtc->irq_hz, vt8500_rtc_irq, IRQF_DISABLED,
    + "rtc 1Hz", dev);
    + if (ret < 0) {
    + dev_err(dev, "can't get irq %i, err %d\n", vt8500_rtc->irq_hz,
    + ret);
    + goto err_irq_hz;
    + }
    + ret = request_irq(vt8500_rtc->irq_alarm, vt8500_rtc_irq, IRQF_DISABLED,
    + "rtc alarm", dev);
    + if (ret < 0) {
    + dev_err(dev, "can't get irq %i, err %d\n",
    + vt8500_rtc->irq_alarm, ret);
    + goto err_irq_alarm;
    + }
    + return 0;
    +
    +err_irq_alarm:
    + free_irq(vt8500_rtc->irq_hz, dev);
    +err_irq_hz:
    + return ret;
    +}
    +
    +static void vt8500_rtc_release(struct device *dev)
    +{
    + struct vt8500_rtc *vt8500_rtc = dev_get_drvdata(dev);
    +
    + spin_lock_irq(&vt8500_rtc->lock);
    + /* Disable alarm matching */
    + writel(0, vt8500_rtc->regbase + VT8500_RTC_IS);
    + spin_unlock_irq(&vt8500_rtc->lock);
    +
    + free_irq(vt8500_rtc->irq_alarm, dev);
    + free_irq(vt8500_rtc->irq_hz, dev);
    +}
    +
    +static int vt8500_rtc_read_time(struct device *dev, struct rtc_time *tm)
    +{
    + struct vt8500_rtc *vt8500_rtc = dev_get_drvdata(dev);
    + u32 date, time;
    +
    + date = readl(vt8500_rtc->regbase + VT8500_RTC_DR);
    + time = readl(vt8500_rtc->regbase + VT8500_RTC_TR);
    +
    + tm->tm_sec = bcd2bin(time & TIME_SEC_MASK);
    + tm->tm_min = bcd2bin((time & TIME_MIN_MASK) >> TIME_MIN_S);
    + tm->tm_hour = bcd2bin((time & TIME_HOUR_MASK) >> TIME_HOUR_S);
    + tm->tm_mday = bcd2bin(date & DATE_DAY_MASK);
    + tm->tm_mon = bcd2bin((date & DATE_MONTH_MASK) >> DATE_MONTH_S);
    + tm->tm_year = bcd2bin((date & DATE_YEAR_MASK) >> DATE_YEAR_S);
    + tm->tm_wday = (time & TIME_DOW_MASK) >> TIME_DOW_S;
    +
    + return 0;
    +}
    +
    +static int vt8500_rtc_set_time(struct device *dev, struct rtc_time *tm)
    +{
    + struct vt8500_rtc *vt8500_rtc = dev_get_drvdata(dev);
    +
    + writel((bin2bcd(tm->tm_year) << DATE_YEAR_S)
    + | (bin2bcd(tm->tm_mon) << DATE_MONTH_S)
    + | (bin2bcd(tm->tm_mday)),
    + vt8500_rtc->regbase + VT8500_RTC_DS);
    + writel((bin2bcd(tm->tm_wday) << TIME_DOW_S)
    + | (bin2bcd(tm->tm_hour) << TIME_HOUR_S)
    + | (bin2bcd(tm->tm_min) << TIME_MIN_S)
    + | (bin2bcd(tm->tm_sec)),
    + vt8500_rtc->regbase + VT8500_RTC_TS);
    +
    + return 0;
    +}
    +
    +static int vt8500_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
    +{
    + struct vt8500_rtc *vt8500_rtc = dev_get_drvdata(dev);
    + u32 isr, alarm;
    +
    + alarm = readl(vt8500_rtc->regbase + VT8500_RTC_AS);
    + isr = readl(vt8500_rtc->regbase + VT8500_RTC_IS);
    +
    + alrm->time.tm_mday = bcd2bin((alarm & ALARM_DAY_MASK) >> ALARM_DAY_S);
    + alrm->time.tm_hour = bcd2bin((alarm & TIME_HOUR_MASK) >> TIME_HOUR_S);
    + alrm->time.tm_min = bcd2bin((alarm & TIME_MIN_MASK) >> TIME_MIN_S);
    + alrm->time.tm_sec = bcd2bin((alarm & TIME_SEC_MASK));
    +
    + alrm->enabled = (alarm & ALARM_ENABLE_MASK) ? 1 : 0;
    +
    + alrm->pending = (isr & 1) ? 1 : 0;
    + return 0;
    +}
    +
    +static int vt8500_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
    +{
    + struct vt8500_rtc *vt8500_rtc = dev_get_drvdata(dev);
    +
    + writel((alrm->enabled ? ALARM_ENABLE_MASK : 0)
    + | (bin2bcd(alrm->time.tm_mday) << ALARM_DAY_S)
    + | (bin2bcd(alrm->time.tm_hour) << TIME_HOUR_S)
    + | (bin2bcd(alrm->time.tm_min) << TIME_MIN_S)
    + | (bin2bcd(alrm->time.tm_sec)),
    + vt8500_rtc->regbase + VT8500_RTC_AS);
    +
    + return 0;
    +}
    +
    +static int vt8500_rtc_ioctl(struct device *dev, unsigned int cmd,
    + unsigned long arg)
    +{
    + struct vt8500_rtc *vt8500_rtc = dev_get_drvdata(dev);
    + int ret = 0;
    + unsigned long tmp;
    +
    + spin_lock_irq(&vt8500_rtc->lock);
    + switch (cmd) {
    + case RTC_AIE_OFF:
    + tmp = readl(vt8500_rtc->regbase + VT8500_RTC_AS);
    + writel(tmp & ~ALARM_ENABLE_MASK,
    + vt8500_rtc->regbase + VT8500_RTC_AS);
    + break;
    + case RTC_AIE_ON:
    + tmp = readl(vt8500_rtc->regbase + VT8500_RTC_AS);
    + writel(tmp | ALARM_ENABLE_MASK,
    + vt8500_rtc->regbase + VT8500_RTC_AS);
    + break;
    + case RTC_UIE_OFF:
    + tmp = readl(vt8500_rtc->regbase + VT8500_RTC_CR);
    + writel(tmp & ~(1 << 2),
    + vt8500_rtc->regbase + VT8500_RTC_CR);
    + break;
    + case RTC_UIE_ON:
    + tmp = readl(vt8500_rtc->regbase + VT8500_RTC_CR);
    + writel(tmp | ((1 << 3) | (1 << 2)),
    + vt8500_rtc->regbase + VT8500_RTC_CR);
    + break;
    + default:
    + ret = -ENOIOCTLCMD;
    + }
    +
    + spin_unlock_irq(&vt8500_rtc->lock);
    + return ret;
    +}
    +
    +static const struct rtc_class_ops vt8500_rtc_ops = {
    + .open = vt8500_rtc_open,
    + .release = vt8500_rtc_release,
    + .ioctl = vt8500_rtc_ioctl,
    + .read_time = vt8500_rtc_read_time,
    + .set_time = vt8500_rtc_set_time,
    + .read_alarm = vt8500_rtc_read_alarm,
    + .set_alarm = vt8500_rtc_set_alarm,
    +};
    +
    +static int __init vt8500_rtc_probe(struct platform_device *pdev)
    +{
    + struct device *dev = &pdev->dev;
    + struct vt8500_rtc *vt8500_rtc;
    + struct resource *res;
    + int ret;
    +
    + vt8500_rtc = kzalloc(sizeof(struct vt8500_rtc), GFP_KERNEL);
    + if (!vt8500_rtc)
    + return -ENOMEM;
    +
    + spin_lock_init(&vt8500_rtc->lock);
    + platform_set_drvdata(pdev, vt8500_rtc);
    +
    + ret = -ENXIO;
    + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    + if (!res) {
    + dev_err(dev, "No I/O memory resource defined\n");
    + goto err_map;
    + }
    +
    + vt8500_rtc->irq_alarm = platform_get_irq(pdev, 0);
    + if (vt8500_rtc->irq_alarm < 0) {
    + dev_err(dev, "No alarm IRQ resource defined\n");
    + goto err_map;
    + }
    +
    + vt8500_rtc->irq_hz = platform_get_irq(pdev, 1);
    + if (vt8500_rtc->irq_hz < 0) {
    + dev_err(dev, "No 1Hz IRQ resource defined\n");
    + goto err_map;
    + }
    +
    + ret = -ENOMEM;
    + vt8500_rtc->regbase = ioremap(res->start, resource_size(res));
    + if (!vt8500_rtc->regbase) {
    + dev_err(&pdev->dev, "Unable to map RTC I/O memory\n");
    + goto err_map;
    + }
    +
    + /* Enable the second/minute interrupt generation and enable RTC */
    + writel((1 << 3) | (1 << 2) | 1, vt8500_rtc->regbase + VT8500_RTC_CR);
    +
    + vt8500_rtc->rtc = rtc_device_register("vt8500-rtc", &pdev->dev,
    + &vt8500_rtc_ops, THIS_MODULE);
    + ret = PTR_ERR(vt8500_rtc->rtc);
    + if (IS_ERR(vt8500_rtc->rtc)) {
    + dev_err(dev, "Failed to register RTC device -> %d\n", ret);
    + goto err_rtc_reg;
    + }
    +
    + device_init_wakeup(dev, 1);
    +
    + return 0;
    +
    +err_rtc_reg:
    + iounmap(vt8500_rtc->regbase);
    +err_map:
    + kfree(vt8500_rtc);
    + return ret;
    +}
    +
    +static int __exit vt8500_rtc_remove(struct platform_device *pdev)
    +{
    + struct vt8500_rtc *vt8500_rtc = platform_get_drvdata(pdev);
    +
    + rtc_device_unregister(vt8500_rtc->rtc);
    +
    + spin_lock_irq(&vt8500_rtc->lock);
    + iounmap(vt8500_rtc->regbase);
    + spin_unlock_irq(&vt8500_rtc->lock);
    +
    + kfree(vt8500_rtc);
    +
    + return 0;
    +}
    +
    +static struct platform_driver vt8500_rtc_driver = {
    + .probe = vt8500_rtc_probe,
    + .remove = __exit_p(vt8500_rtc_remove),
    + .driver = {
    + .name = "vt8500-rtc"
    + },
    +};
    +
    +static int __init vt8500_rtc_init(void)
    +{
    + return platform_driver_register(&vt8500_rtc_driver);
    +}
    +
    +static void __exit vt8500_rtc_exit(void)
    +{
    + platform_driver_unregister(&vt8500_rtc_driver);
    +}
    +
    +module_init(vt8500_rtc_init);
    +module_exit(vt8500_rtc_exit);
    +
    +MODULE_AUTHOR("Alexey Charkov <alchark@gmail.com>");
    +MODULE_DESCRIPTION("VIA VT8500 SoC Realtime Clock Driver (RTC)");
    +MODULE_LICENSE("GPL");
    +MODULE_ALIAS("platform:vt8500-rtc");
    --
    1.7.3.2


    \
     
     \ /
      Last update: 2010-11-07 17:35    [W:0.042 / U:0.140 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site