blob: 2939cdcb268855178ee77b469e470f8cff26881f [file] [log] [blame]
dmitry pervushindf17f632009-09-22 16:46:26 -07001/*
2 * Freescale STMP37XX/STMP378X Real Time Clock driver
3 *
4 * Copyright (c) 2007 Sigmatel, Inc.
5 * Peter Hartley, <peter.hartley@sigmatel.com>
6 *
7 * Copyright 2008 Freescale Semiconductor, Inc. All Rights Reserved.
8 * Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved.
Wolfram Sang7e794cb2011-05-25 12:56:53 +02009 * Copyright 2011 Wolfram Sang, Pengutronix e.K.
dmitry pervushindf17f632009-09-22 16:46:26 -070010 */
11
12/*
13 * The code contained herein is licensed under the GNU General Public
14 * License. You may obtain a copy of the GNU General Public License
15 * Version 2 or later at the following locations:
16 *
17 * http://www.opensource.org/licenses/gpl-license.html
18 * http://www.gnu.org/copyleft/gpl.html
19 */
20#include <linux/kernel.h>
21#include <linux/module.h>
Wolfram Sangb5167152011-05-25 12:56:52 +020022#include <linux/io.h>
dmitry pervushindf17f632009-09-22 16:46:26 -070023#include <linux/init.h>
24#include <linux/platform_device.h>
25#include <linux/interrupt.h>
Lothar Waßmann28a0c882013-08-13 16:00:56 -070026#include <linux/delay.h>
dmitry pervushindf17f632009-09-22 16:46:26 -070027#include <linux/rtc.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090028#include <linux/slab.h>
Marek Vasutdd8d20a2012-06-26 16:29:27 +080029#include <linux/of_device.h>
Sachin Kamatc8a60462013-02-21 16:44:28 -080030#include <linux/of.h>
Wolfram Sang1a71fb82011-09-27 22:21:37 +020031#include <linux/stmp_device.h>
32#include <linux/stmp3xxx_rtc_wdt.h>
dmitry pervushindf17f632009-09-22 16:46:26 -070033
Wolfram Sang47eac332011-05-25 12:56:49 +020034#define STMP3XXX_RTC_CTRL 0x0
Wolfram Sangb5167152011-05-25 12:56:52 +020035#define STMP3XXX_RTC_CTRL_SET 0x4
36#define STMP3XXX_RTC_CTRL_CLR 0x8
Wolfram Sang47eac332011-05-25 12:56:49 +020037#define STMP3XXX_RTC_CTRL_ALARM_IRQ_EN 0x00000001
38#define STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN 0x00000002
39#define STMP3XXX_RTC_CTRL_ALARM_IRQ 0x00000004
Wolfram Sang1a71fb82011-09-27 22:21:37 +020040#define STMP3XXX_RTC_CTRL_WATCHDOGEN 0x00000010
Wolfram Sang47eac332011-05-25 12:56:49 +020041
42#define STMP3XXX_RTC_STAT 0x10
43#define STMP3XXX_RTC_STAT_STALE_SHIFT 16
44#define STMP3XXX_RTC_STAT_RTC_PRESENT 0x80000000
45
46#define STMP3XXX_RTC_SECONDS 0x30
47
48#define STMP3XXX_RTC_ALARM 0x40
49
Wolfram Sang1a71fb82011-09-27 22:21:37 +020050#define STMP3XXX_RTC_WATCHDOG 0x50
51
Wolfram Sang47eac332011-05-25 12:56:49 +020052#define STMP3XXX_RTC_PERSISTENT0 0x60
Wolfram Sangb5167152011-05-25 12:56:52 +020053#define STMP3XXX_RTC_PERSISTENT0_SET 0x64
54#define STMP3XXX_RTC_PERSISTENT0_CLR 0x68
Wolfram Sang47eac332011-05-25 12:56:49 +020055#define STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN 0x00000002
56#define STMP3XXX_RTC_PERSISTENT0_ALARM_EN 0x00000004
57#define STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE 0x00000080
dmitry pervushindf17f632009-09-22 16:46:26 -070058
Wolfram Sang1a71fb82011-09-27 22:21:37 +020059#define STMP3XXX_RTC_PERSISTENT1 0x70
60/* missing bitmask in headers */
61#define STMP3XXX_RTC_PERSISTENT1_FORCE_UPDATER 0x80000000
62
dmitry pervushindf17f632009-09-22 16:46:26 -070063struct stmp3xxx_rtc_data {
64 struct rtc_device *rtc;
dmitry pervushindf17f632009-09-22 16:46:26 -070065 void __iomem *io;
Wolfram Sang7e794cb2011-05-25 12:56:53 +020066 int irq_alarm;
dmitry pervushindf17f632009-09-22 16:46:26 -070067};
68
Wolfram Sang1a71fb82011-09-27 22:21:37 +020069#if IS_ENABLED(CONFIG_STMP3XXX_RTC_WATCHDOG)
70/**
71 * stmp3xxx_wdt_set_timeout - configure the watchdog inside the STMP3xxx RTC
72 * @dev: the parent device of the watchdog (= the RTC)
73 * @timeout: the desired value for the timeout register of the watchdog.
74 * 0 disables the watchdog
75 *
76 * The watchdog needs one register and two bits which are in the RTC domain.
77 * To handle the resource conflict, the RTC driver will create another
78 * platform_device for the watchdog driver as a child of the RTC device.
79 * The watchdog driver is passed the below accessor function via platform_data
80 * to configure the watchdog. Locking is not needed because accessing SET/CLR
81 * registers is atomic.
82 */
83
84static void stmp3xxx_wdt_set_timeout(struct device *dev, u32 timeout)
85{
86 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
87
88 if (timeout) {
89 writel(timeout, rtc_data->io + STMP3XXX_RTC_WATCHDOG);
90 writel(STMP3XXX_RTC_CTRL_WATCHDOGEN,
91 rtc_data->io + STMP3XXX_RTC_CTRL + STMP_OFFSET_REG_SET);
92 writel(STMP3XXX_RTC_PERSISTENT1_FORCE_UPDATER,
93 rtc_data->io + STMP3XXX_RTC_PERSISTENT1 + STMP_OFFSET_REG_SET);
94 } else {
95 writel(STMP3XXX_RTC_CTRL_WATCHDOGEN,
96 rtc_data->io + STMP3XXX_RTC_CTRL + STMP_OFFSET_REG_CLR);
97 writel(STMP3XXX_RTC_PERSISTENT1_FORCE_UPDATER,
98 rtc_data->io + STMP3XXX_RTC_PERSISTENT1 + STMP_OFFSET_REG_CLR);
99 }
100}
101
102static struct stmp3xxx_wdt_pdata wdt_pdata = {
103 .wdt_set_timeout = stmp3xxx_wdt_set_timeout,
104};
105
106static void stmp3xxx_wdt_register(struct platform_device *rtc_pdev)
107{
108 struct platform_device *wdt_pdev =
109 platform_device_alloc("stmp3xxx_rtc_wdt", rtc_pdev->id);
110
111 if (wdt_pdev) {
112 wdt_pdev->dev.parent = &rtc_pdev->dev;
113 wdt_pdev->dev.platform_data = &wdt_pdata;
114 platform_device_add(wdt_pdev);
115 }
116}
117#else
118static void stmp3xxx_wdt_register(struct platform_device *rtc_pdev)
119{
120}
121#endif /* CONFIG_STMP3XXX_RTC_WATCHDOG */
122
Lothar Waßmann28a0c882013-08-13 16:00:56 -0700123static int stmp3xxx_wait_time(struct stmp3xxx_rtc_data *rtc_data)
dmitry pervushindf17f632009-09-22 16:46:26 -0700124{
Lothar Waßmann28a0c882013-08-13 16:00:56 -0700125 int timeout = 5000; /* 3ms according to i.MX28 Ref Manual */
dmitry pervushindf17f632009-09-22 16:46:26 -0700126 /*
Lothar Waßmann28a0c882013-08-13 16:00:56 -0700127 * The i.MX28 Applications Processor Reference Manual, Rev. 1, 2010
128 * states:
129 * | The order in which registers are updated is
130 * | Persistent 0, 1, 2, 3, 4, 5, Alarm, Seconds.
131 * | (This list is in bitfield order, from LSB to MSB, as they would
132 * | appear in the STALE_REGS and NEW_REGS bitfields of the HW_RTC_STAT
133 * | register. For example, the Seconds register corresponds to
134 * | STALE_REGS or NEW_REGS containing 0x80.)
dmitry pervushindf17f632009-09-22 16:46:26 -0700135 */
Lothar Waßmann28a0c882013-08-13 16:00:56 -0700136 do {
137 if (!(readl(rtc_data->io + STMP3XXX_RTC_STAT) &
138 (0x80 << STMP3XXX_RTC_STAT_STALE_SHIFT)))
139 return 0;
140 udelay(1);
141 } while (--timeout > 0);
142 return (readl(rtc_data->io + STMP3XXX_RTC_STAT) &
143 (0x80 << STMP3XXX_RTC_STAT_STALE_SHIFT)) ? -ETIME : 0;
dmitry pervushindf17f632009-09-22 16:46:26 -0700144}
145
146/* Time read/write */
147static int stmp3xxx_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
148{
Lothar Waßmann28a0c882013-08-13 16:00:56 -0700149 int ret;
dmitry pervushindf17f632009-09-22 16:46:26 -0700150 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
151
Lothar Waßmann28a0c882013-08-13 16:00:56 -0700152 ret = stmp3xxx_wait_time(rtc_data);
153 if (ret)
154 return ret;
155
Wolfram Sangb5167152011-05-25 12:56:52 +0200156 rtc_time_to_tm(readl(rtc_data->io + STMP3XXX_RTC_SECONDS), rtc_tm);
dmitry pervushindf17f632009-09-22 16:46:26 -0700157 return 0;
158}
159
160static int stmp3xxx_rtc_set_mmss(struct device *dev, unsigned long t)
161{
162 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
163
Wolfram Sangb5167152011-05-25 12:56:52 +0200164 writel(t, rtc_data->io + STMP3XXX_RTC_SECONDS);
Lothar Waßmann28a0c882013-08-13 16:00:56 -0700165 return stmp3xxx_wait_time(rtc_data);
dmitry pervushindf17f632009-09-22 16:46:26 -0700166}
167
168/* interrupt(s) handler */
169static irqreturn_t stmp3xxx_rtc_interrupt(int irq, void *dev_id)
170{
171 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev_id);
Wolfram Sang7e794cb2011-05-25 12:56:53 +0200172 u32 status = readl(rtc_data->io + STMP3XXX_RTC_CTRL);
dmitry pervushindf17f632009-09-22 16:46:26 -0700173
Wolfram Sang47eac332011-05-25 12:56:49 +0200174 if (status & STMP3XXX_RTC_CTRL_ALARM_IRQ) {
Wolfram Sangb5167152011-05-25 12:56:52 +0200175 writel(STMP3XXX_RTC_CTRL_ALARM_IRQ,
176 rtc_data->io + STMP3XXX_RTC_CTRL_CLR);
Wolfram Sang7e794cb2011-05-25 12:56:53 +0200177 rtc_update_irq(rtc_data->rtc, 1, RTC_AF | RTC_IRQF);
178 return IRQ_HANDLED;
dmitry pervushindf17f632009-09-22 16:46:26 -0700179 }
180
Wolfram Sang7e794cb2011-05-25 12:56:53 +0200181 return IRQ_NONE;
dmitry pervushindf17f632009-09-22 16:46:26 -0700182}
183
184static int stmp3xxx_alarm_irq_enable(struct device *dev, unsigned int enabled)
185{
186 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
dmitry pervushindf17f632009-09-22 16:46:26 -0700187
188 if (enabled) {
Wolfram Sangb5167152011-05-25 12:56:52 +0200189 writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
190 STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN,
191 rtc_data->io + STMP3XXX_RTC_PERSISTENT0_SET);
192 writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
193 rtc_data->io + STMP3XXX_RTC_CTRL_SET);
dmitry pervushindf17f632009-09-22 16:46:26 -0700194 } else {
Wolfram Sangb5167152011-05-25 12:56:52 +0200195 writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
196 STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN,
197 rtc_data->io + STMP3XXX_RTC_PERSISTENT0_CLR);
198 writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
199 rtc_data->io + STMP3XXX_RTC_CTRL_CLR);
dmitry pervushindf17f632009-09-22 16:46:26 -0700200 }
201 return 0;
202}
203
dmitry pervushindf17f632009-09-22 16:46:26 -0700204static int stmp3xxx_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
205{
206 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
207
Wolfram Sangb5167152011-05-25 12:56:52 +0200208 rtc_time_to_tm(readl(rtc_data->io + STMP3XXX_RTC_ALARM), &alm->time);
dmitry pervushindf17f632009-09-22 16:46:26 -0700209 return 0;
210}
211
212static int stmp3xxx_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
213{
214 unsigned long t;
215 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
216
217 rtc_tm_to_time(&alm->time, &t);
Wolfram Sangb5167152011-05-25 12:56:52 +0200218 writel(t, rtc_data->io + STMP3XXX_RTC_ALARM);
Wolfram Sang7e794cb2011-05-25 12:56:53 +0200219
220 stmp3xxx_alarm_irq_enable(dev, alm->enabled);
221
dmitry pervushindf17f632009-09-22 16:46:26 -0700222 return 0;
223}
224
225static struct rtc_class_ops stmp3xxx_rtc_ops = {
226 .alarm_irq_enable =
227 stmp3xxx_alarm_irq_enable,
dmitry pervushindf17f632009-09-22 16:46:26 -0700228 .read_time = stmp3xxx_rtc_gettime,
229 .set_mmss = stmp3xxx_rtc_set_mmss,
230 .read_alarm = stmp3xxx_rtc_read_alarm,
231 .set_alarm = stmp3xxx_rtc_set_alarm,
232};
233
234static int stmp3xxx_rtc_remove(struct platform_device *pdev)
235{
236 struct stmp3xxx_rtc_data *rtc_data = platform_get_drvdata(pdev);
237
238 if (!rtc_data)
239 return 0;
240
Wolfram Sang7e794cb2011-05-25 12:56:53 +0200241 writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
Wolfram Sangb5167152011-05-25 12:56:52 +0200242 rtc_data->io + STMP3XXX_RTC_CTRL_CLR);
dmitry pervushindf17f632009-09-22 16:46:26 -0700243
244 return 0;
245}
246
247static int stmp3xxx_rtc_probe(struct platform_device *pdev)
248{
249 struct stmp3xxx_rtc_data *rtc_data;
250 struct resource *r;
251 int err;
252
Jingoo Han87a81422013-04-29 16:20:55 -0700253 rtc_data = devm_kzalloc(&pdev->dev, sizeof(*rtc_data), GFP_KERNEL);
dmitry pervushindf17f632009-09-22 16:46:26 -0700254 if (!rtc_data)
255 return -ENOMEM;
256
257 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
258 if (!r) {
259 dev_err(&pdev->dev, "failed to get resource\n");
Jingoo Han87a81422013-04-29 16:20:55 -0700260 return -ENXIO;
dmitry pervushindf17f632009-09-22 16:46:26 -0700261 }
262
Jingoo Han87a81422013-04-29 16:20:55 -0700263 rtc_data->io = devm_ioremap(&pdev->dev, r->start, resource_size(r));
dmitry pervushindf17f632009-09-22 16:46:26 -0700264 if (!rtc_data->io) {
265 dev_err(&pdev->dev, "ioremap failed\n");
Jingoo Han87a81422013-04-29 16:20:55 -0700266 return -EIO;
dmitry pervushindf17f632009-09-22 16:46:26 -0700267 }
268
269 rtc_data->irq_alarm = platform_get_irq(pdev, 0);
dmitry pervushindf17f632009-09-22 16:46:26 -0700270
Wolfram Sangb5167152011-05-25 12:56:52 +0200271 if (!(readl(STMP3XXX_RTC_STAT + rtc_data->io) &
Wolfram Sang47eac332011-05-25 12:56:49 +0200272 STMP3XXX_RTC_STAT_RTC_PRESENT)) {
dmitry pervushindf17f632009-09-22 16:46:26 -0700273 dev_err(&pdev->dev, "no device onboard\n");
Jingoo Han87a81422013-04-29 16:20:55 -0700274 return -ENODEV;
dmitry pervushindf17f632009-09-22 16:46:26 -0700275 }
276
Wolfram Sanga91d2ba2011-05-25 12:56:51 +0200277 platform_set_drvdata(pdev, rtc_data);
278
Fabio Estevam4e80b182013-07-08 16:00:45 -0700279 err = stmp_reset_block(rtc_data->io);
280 if (err) {
281 dev_err(&pdev->dev, "stmp_reset_block failed: %d\n", err);
282 return err;
283 }
284
Wolfram Sangb5167152011-05-25 12:56:52 +0200285 writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
Wolfram Sang47eac332011-05-25 12:56:49 +0200286 STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN |
287 STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE,
Wolfram Sangb5167152011-05-25 12:56:52 +0200288 rtc_data->io + STMP3XXX_RTC_PERSISTENT0_CLR);
Wolfram Sanga91d2ba2011-05-25 12:56:51 +0200289
Wolfram Sang7e794cb2011-05-25 12:56:53 +0200290 writel(STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN |
291 STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
292 rtc_data->io + STMP3XXX_RTC_CTRL_CLR);
293
Jingoo Han87a81422013-04-29 16:20:55 -0700294 rtc_data->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
dmitry pervushindf17f632009-09-22 16:46:26 -0700295 &stmp3xxx_rtc_ops, THIS_MODULE);
Jingoo Handfd2a172013-07-03 15:06:37 -0700296 if (IS_ERR(rtc_data->rtc))
297 return PTR_ERR(rtc_data->rtc);
dmitry pervushindf17f632009-09-22 16:46:26 -0700298
Jingoo Han87a81422013-04-29 16:20:55 -0700299 err = devm_request_irq(&pdev->dev, rtc_data->irq_alarm,
300 stmp3xxx_rtc_interrupt, 0, "RTC alarm", &pdev->dev);
dmitry pervushindf17f632009-09-22 16:46:26 -0700301 if (err) {
302 dev_err(&pdev->dev, "Cannot claim IRQ%d\n",
303 rtc_data->irq_alarm);
Jingoo Handfd2a172013-07-03 15:06:37 -0700304 return err;
dmitry pervushindf17f632009-09-22 16:46:26 -0700305 }
dmitry pervushindf17f632009-09-22 16:46:26 -0700306
Wolfram Sang1a71fb82011-09-27 22:21:37 +0200307 stmp3xxx_wdt_register(pdev);
dmitry pervushindf17f632009-09-22 16:46:26 -0700308 return 0;
dmitry pervushindf17f632009-09-22 16:46:26 -0700309}
310
Jingoo Hanef69a7f2013-04-29 16:21:03 -0700311#ifdef CONFIG_PM_SLEEP
312static int stmp3xxx_rtc_suspend(struct device *dev)
dmitry pervushindf17f632009-09-22 16:46:26 -0700313{
314 return 0;
315}
316
Jingoo Hanef69a7f2013-04-29 16:21:03 -0700317static int stmp3xxx_rtc_resume(struct device *dev)
dmitry pervushindf17f632009-09-22 16:46:26 -0700318{
Jingoo Hanef69a7f2013-04-29 16:21:03 -0700319 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
dmitry pervushindf17f632009-09-22 16:46:26 -0700320
Shawn Guo36d1da12013-03-28 23:13:14 +0800321 stmp_reset_block(rtc_data->io);
Wolfram Sangb5167152011-05-25 12:56:52 +0200322 writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
Wolfram Sang47eac332011-05-25 12:56:49 +0200323 STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN |
324 STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE,
Wolfram Sangb5167152011-05-25 12:56:52 +0200325 rtc_data->io + STMP3XXX_RTC_PERSISTENT0_CLR);
dmitry pervushindf17f632009-09-22 16:46:26 -0700326 return 0;
327}
dmitry pervushindf17f632009-09-22 16:46:26 -0700328#endif
329
Jingoo Hanef69a7f2013-04-29 16:21:03 -0700330static SIMPLE_DEV_PM_OPS(stmp3xxx_rtc_pm_ops, stmp3xxx_rtc_suspend,
331 stmp3xxx_rtc_resume);
332
Marek Vasutdd8d20a2012-06-26 16:29:27 +0800333static const struct of_device_id rtc_dt_ids[] = {
334 { .compatible = "fsl,stmp3xxx-rtc", },
335 { /* sentinel */ }
336};
337MODULE_DEVICE_TABLE(of, rtc_dt_ids);
338
dmitry pervushindf17f632009-09-22 16:46:26 -0700339static struct platform_driver stmp3xxx_rtcdrv = {
340 .probe = stmp3xxx_rtc_probe,
341 .remove = stmp3xxx_rtc_remove,
dmitry pervushindf17f632009-09-22 16:46:26 -0700342 .driver = {
343 .name = "stmp3xxx-rtc",
Jingoo Hanef69a7f2013-04-29 16:21:03 -0700344 .pm = &stmp3xxx_rtc_pm_ops,
Sachin Kamat462a4652013-11-12 15:10:58 -0800345 .of_match_table = rtc_dt_ids,
dmitry pervushindf17f632009-09-22 16:46:26 -0700346 },
347};
348
Axel Lin0c4eae62012-01-10 15:10:48 -0800349module_platform_driver(stmp3xxx_rtcdrv);
dmitry pervushindf17f632009-09-22 16:46:26 -0700350
351MODULE_DESCRIPTION("STMP3xxx RTC Driver");
Wolfram Sang7e794cb2011-05-25 12:56:53 +0200352MODULE_AUTHOR("dmitry pervushin <dpervushin@embeddedalley.com> and "
353 "Wolfram Sang <w.sang@pengutronix.de>");
dmitry pervushindf17f632009-09-22 16:46:26 -0700354MODULE_LICENSE("GPL");