2 * Freescale STMP37XX/STMP378X Real Time Clock driver
4 * Copyright (c) 2007 Sigmatel, Inc.
5 * Peter Hartley, <peter.hartley@sigmatel.com>
7 * Copyright 2008 Freescale Semiconductor, Inc. All Rights Reserved.
8 * Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved.
12 * The code contained herein is licensed under the GNU General Public
13 * License. You may obtain a copy of the GNU General Public License
14 * Version 2 or later at the following locations:
16 * http://www.opensource.org/licenses/gpl-license.html
17 * http://www.gnu.org/copyleft/gpl.html
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/init.h>
22 #include <linux/platform_device.h>
23 #include <linux/interrupt.h>
24 #include <linux/rtc.h>
26 #include <mach/platform.h>
27 #include <mach/stmp3xxx.h>
28 #include <mach/regs-rtc.h>
30 struct stmp3xxx_rtc_data {
31 struct rtc_device *rtc;
34 int irq_alarm, irq_1msec;
37 static void stmp3xxx_wait_time(struct stmp3xxx_rtc_data *rtc_data)
40 * The datasheet doesn't say which way round the
41 * NEW_REGS/STALE_REGS bitfields go. In fact it's 0x1=P0,
42 * 0x2=P1, .., 0x20=P5, 0x40=ALARM, 0x80=SECONDS
44 while (__raw_readl(rtc_data->io + HW_RTC_STAT) &
45 BF(0x80, RTC_STAT_STALE_REGS))
50 static int stmp3xxx_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
52 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
54 stmp3xxx_wait_time(rtc_data);
55 rtc_time_to_tm(__raw_readl(rtc_data->io + HW_RTC_SECONDS), rtc_tm);
59 static int stmp3xxx_rtc_set_mmss(struct device *dev, unsigned long t)
61 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
63 __raw_writel(t, rtc_data->io + HW_RTC_SECONDS);
64 stmp3xxx_wait_time(rtc_data);
68 /* interrupt(s) handler */
69 static irqreturn_t stmp3xxx_rtc_interrupt(int irq, void *dev_id)
71 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev_id);
75 status = __raw_readl(rtc_data->io + HW_RTC_CTRL) &
76 (BM_RTC_CTRL_ALARM_IRQ | BM_RTC_CTRL_ONEMSEC_IRQ);
78 if (status & BM_RTC_CTRL_ALARM_IRQ) {
79 stmp3xxx_clearl(BM_RTC_CTRL_ALARM_IRQ,
80 rtc_data->io + HW_RTC_CTRL);
81 events |= RTC_AF | RTC_IRQF;
84 if (status & BM_RTC_CTRL_ONEMSEC_IRQ) {
85 stmp3xxx_clearl(BM_RTC_CTRL_ONEMSEC_IRQ,
86 rtc_data->io + HW_RTC_CTRL);
87 if (++rtc_data->irq_count % 1000 == 0) {
88 events |= RTC_UF | RTC_IRQF;
89 rtc_data->irq_count = 0;
94 rtc_update_irq(rtc_data->rtc, 1, events);
99 static int stmp3xxx_alarm_irq_enable(struct device *dev, unsigned int enabled)
101 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
102 void __iomem *p = rtc_data->io + HW_RTC_PERSISTENT0,
103 *ctl = rtc_data->io + HW_RTC_CTRL;
106 stmp3xxx_setl(BM_RTC_PERSISTENT0_ALARM_EN |
107 BM_RTC_PERSISTENT0_ALARM_WAKE_EN, p);
108 stmp3xxx_setl(BM_RTC_CTRL_ALARM_IRQ_EN, ctl);
110 stmp3xxx_clearl(BM_RTC_PERSISTENT0_ALARM_EN |
111 BM_RTC_PERSISTENT0_ALARM_WAKE_EN, p);
112 stmp3xxx_clearl(BM_RTC_CTRL_ALARM_IRQ_EN, ctl);
117 static int stmp3xxx_update_irq_enable(struct device *dev, unsigned int enabled)
119 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
122 stmp3xxx_setl(BM_RTC_CTRL_ONEMSEC_IRQ_EN,
123 rtc_data->io + HW_RTC_CTRL);
125 stmp3xxx_clearl(BM_RTC_CTRL_ONEMSEC_IRQ_EN,
126 rtc_data->io + HW_RTC_CTRL);
130 static int stmp3xxx_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
132 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
134 rtc_time_to_tm(__raw_readl(rtc_data->io + HW_RTC_ALARM), &alm->time);
138 static int stmp3xxx_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
141 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
143 rtc_tm_to_time(&alm->time, &t);
144 __raw_writel(t, rtc_data->io + HW_RTC_ALARM);
148 static struct rtc_class_ops stmp3xxx_rtc_ops = {
150 stmp3xxx_alarm_irq_enable,
152 stmp3xxx_update_irq_enable,
153 .read_time = stmp3xxx_rtc_gettime,
154 .set_mmss = stmp3xxx_rtc_set_mmss,
155 .read_alarm = stmp3xxx_rtc_read_alarm,
156 .set_alarm = stmp3xxx_rtc_set_alarm,
159 static int stmp3xxx_rtc_remove(struct platform_device *pdev)
161 struct stmp3xxx_rtc_data *rtc_data = platform_get_drvdata(pdev);
166 stmp3xxx_clearl(BM_RTC_CTRL_ONEMSEC_IRQ_EN | BM_RTC_CTRL_ALARM_IRQ_EN,
167 rtc_data->io + HW_RTC_CTRL);
168 free_irq(rtc_data->irq_alarm, &pdev->dev);
169 free_irq(rtc_data->irq_1msec, &pdev->dev);
170 rtc_device_unregister(rtc_data->rtc);
171 iounmap(rtc_data->io);
177 static int stmp3xxx_rtc_probe(struct platform_device *pdev)
179 struct stmp3xxx_rtc_data *rtc_data;
183 rtc_data = kzalloc(sizeof *rtc_data, GFP_KERNEL);
187 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
189 dev_err(&pdev->dev, "failed to get resource\n");
194 rtc_data->io = ioremap(r->start, resource_size(r));
196 dev_err(&pdev->dev, "ioremap failed\n");
201 rtc_data->irq_alarm = platform_get_irq(pdev, 0);
202 rtc_data->irq_1msec = platform_get_irq(pdev, 1);
204 if (!(__raw_readl(HW_RTC_STAT + rtc_data->io) &
205 BM_RTC_STAT_RTC_PRESENT)) {
206 dev_err(&pdev->dev, "no device onboard\n");
211 stmp3xxx_reset_block(rtc_data->io, true);
212 stmp3xxx_clearl(BM_RTC_PERSISTENT0_ALARM_EN |
213 BM_RTC_PERSISTENT0_ALARM_WAKE_EN |
214 BM_RTC_PERSISTENT0_ALARM_WAKE,
215 rtc_data->io + HW_RTC_PERSISTENT0);
216 rtc_data->rtc = rtc_device_register(pdev->name, &pdev->dev,
217 &stmp3xxx_rtc_ops, THIS_MODULE);
218 if (IS_ERR(rtc_data->rtc)) {
219 err = PTR_ERR(rtc_data->rtc);
223 rtc_data->irq_count = 0;
224 err = request_irq(rtc_data->irq_alarm, stmp3xxx_rtc_interrupt,
225 IRQF_DISABLED, "RTC alarm", &pdev->dev);
227 dev_err(&pdev->dev, "Cannot claim IRQ%d\n",
228 rtc_data->irq_alarm);
231 err = request_irq(rtc_data->irq_1msec, stmp3xxx_rtc_interrupt,
232 IRQF_DISABLED, "RTC tick", &pdev->dev);
234 dev_err(&pdev->dev, "Cannot claim IRQ%d\n",
235 rtc_data->irq_1msec);
239 platform_set_drvdata(pdev, rtc_data);
244 free_irq(rtc_data->irq_alarm, &pdev->dev);
246 stmp3xxx_clearl(BM_RTC_CTRL_ONEMSEC_IRQ_EN | BM_RTC_CTRL_ALARM_IRQ_EN,
247 rtc_data->io + HW_RTC_CTRL);
248 rtc_device_unregister(rtc_data->rtc);
250 iounmap(rtc_data->io);
257 static int stmp3xxx_rtc_suspend(struct platform_device *dev, pm_message_t state)
262 static int stmp3xxx_rtc_resume(struct platform_device *dev)
264 struct stmp3xxx_rtc_data *rtc_data = platform_get_drvdata(dev);
266 stmp3xxx_reset_block(rtc_data->io, true);
267 stmp3xxx_clearl(BM_RTC_PERSISTENT0_ALARM_EN |
268 BM_RTC_PERSISTENT0_ALARM_WAKE_EN |
269 BM_RTC_PERSISTENT0_ALARM_WAKE,
270 rtc_data->io + HW_RTC_PERSISTENT0);
274 #define stmp3xxx_rtc_suspend NULL
275 #define stmp3xxx_rtc_resume NULL
278 static struct platform_driver stmp3xxx_rtcdrv = {
279 .probe = stmp3xxx_rtc_probe,
280 .remove = stmp3xxx_rtc_remove,
281 .suspend = stmp3xxx_rtc_suspend,
282 .resume = stmp3xxx_rtc_resume,
284 .name = "stmp3xxx-rtc",
285 .owner = THIS_MODULE,
289 static int __init stmp3xxx_rtc_init(void)
291 return platform_driver_register(&stmp3xxx_rtcdrv);
294 static void __exit stmp3xxx_rtc_exit(void)
296 platform_driver_unregister(&stmp3xxx_rtcdrv);
299 module_init(stmp3xxx_rtc_init);
300 module_exit(stmp3xxx_rtc_exit);
302 MODULE_DESCRIPTION("STMP3xxx RTC Driver");
303 MODULE_AUTHOR("dmitry pervushin <dpervushin@embeddedalley.com>");
304 MODULE_LICENSE("GPL");