| /* |
| * 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 <linux/slab.h> |
| |
| #include <mach/common.h> |
| #include <mach/mxs.h> |
| |
| #define STMP3XXX_RTC_CTRL 0x0 |
| #define STMP3XXX_RTC_CTRL_ALARM_IRQ_EN 0x00000001 |
| #define STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN 0x00000002 |
| #define STMP3XXX_RTC_CTRL_ALARM_IRQ 0x00000004 |
| #define STMP3XXX_RTC_CTRL_ONEMSEC_IRQ 0x00000008 |
| |
| #define STMP3XXX_RTC_STAT 0x10 |
| #define STMP3XXX_RTC_STAT_STALE_SHIFT 16 |
| #define STMP3XXX_RTC_STAT_RTC_PRESENT 0x80000000 |
| |
| #define STMP3XXX_RTC_SECONDS 0x30 |
| |
| #define STMP3XXX_RTC_ALARM 0x40 |
| |
| #define STMP3XXX_RTC_PERSISTENT0 0x60 |
| #define STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN 0x00000002 |
| #define STMP3XXX_RTC_PERSISTENT0_ALARM_EN 0x00000004 |
| #define STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE 0x00000080 |
| |
| 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 + STMP3XXX_RTC_STAT) & |
| (0x80 << STMP3XXX_RTC_STAT_STALE_SHIFT)) |
| 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 + STMP3XXX_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 + STMP3XXX_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 + STMP3XXX_RTC_CTRL) & |
| (STMP3XXX_RTC_CTRL_ALARM_IRQ | |
| STMP3XXX_RTC_CTRL_ONEMSEC_IRQ); |
| |
| if (status & STMP3XXX_RTC_CTRL_ALARM_IRQ) { |
| __mxs_clrl(STMP3XXX_RTC_CTRL_ALARM_IRQ, |
| rtc_data->io + STMP3XXX_RTC_CTRL); |
| events |= RTC_AF | RTC_IRQF; |
| } |
| |
| if (status & STMP3XXX_RTC_CTRL_ONEMSEC_IRQ) { |
| __mxs_clrl(STMP3XXX_RTC_CTRL_ONEMSEC_IRQ, |
| rtc_data->io + STMP3XXX_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 + STMP3XXX_RTC_PERSISTENT0, |
| *ctl = rtc_data->io + STMP3XXX_RTC_CTRL; |
| |
| if (enabled) { |
| __mxs_setl(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | |
| STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN, p); |
| __mxs_setl(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN, ctl); |
| } else { |
| __mxs_clrl(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | |
| STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN, p); |
| __mxs_clrl(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN, ctl); |
| } |
| 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 + STMP3XXX_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 + STMP3XXX_RTC_ALARM); |
| return 0; |
| } |
| |
| static struct rtc_class_ops stmp3xxx_rtc_ops = { |
| .alarm_irq_enable = |
| stmp3xxx_alarm_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; |
| |
| __mxs_clrl(STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN | |
| STMP3XXX_RTC_CTRL_ALARM_IRQ_EN, |
| rtc_data->io + STMP3XXX_RTC_CTRL); |
| free_irq(rtc_data->irq_alarm, &pdev->dev); |
| free_irq(rtc_data->irq_1msec, &pdev->dev); |
| rtc_device_unregister(rtc_data->rtc); |
| platform_set_drvdata(pdev, NULL); |
| 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(STMP3XXX_RTC_STAT + rtc_data->io) & |
| STMP3XXX_RTC_STAT_RTC_PRESENT)) { |
| dev_err(&pdev->dev, "no device onboard\n"); |
| err = -ENODEV; |
| goto out_remap; |
| } |
| |
| platform_set_drvdata(pdev, rtc_data); |
| |
| mxs_reset_block(rtc_data->io); |
| __mxs_clrl(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | |
| STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN | |
| STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE, |
| rtc_data->io + STMP3XXX_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; |
| } |
| |
| return 0; |
| |
| out_irq1: |
| free_irq(rtc_data->irq_alarm, &pdev->dev); |
| out_irq_alarm: |
| __mxs_clrl(STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN | |
| STMP3XXX_RTC_CTRL_ALARM_IRQ_EN, |
| rtc_data->io + STMP3XXX_RTC_CTRL); |
| rtc_device_unregister(rtc_data->rtc); |
| out_remap: |
| platform_set_drvdata(pdev, NULL); |
| 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); |
| |
| mxs_reset_block(rtc_data->io); |
| __mxs_clrl(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | |
| STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN | |
| STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE, |
| rtc_data->io + STMP3XXX_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"); |