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authordmitry pervushin <dpervushin@embeddedalley.com>2009-09-22 19:46:26 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2009-09-23 10:39:45 -0400
commitdf17f63173bcfcc8b4b90f63bf88f54ca0dd2dd7 (patch)
treeeaa04e59ee51ef63801e70135db0668869be8eb5 /drivers/rtc/rtc-stmp3xxx.c
parent6bff5fb80b86b461a233eaea4da769ba1b349cbe (diff)
rtc: add Freescale stmp37xx/378x driver
Add support for RTC on the Freescale STMP37xx/378x platform. Signed-off-by: dmitry pervushin <dpervushin@embeddedalley.com> Signed-off-by: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/rtc/rtc-stmp3xxx.c')
-rw-r--r--drivers/rtc/rtc-stmp3xxx.c304
1 files changed, 304 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-stmp3xxx.c b/drivers/rtc/rtc-stmp3xxx.c
new file mode 100644
index 000000000000..d7ce1a5c857d
--- /dev/null
+++ b/drivers/rtc/rtc-stmp3xxx.c
@@ -0,0 +1,304 @@
1/*
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.
9 */
10
11/*
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:
15 *
16 * http://www.opensource.org/licenses/gpl-license.html
17 * http://www.gnu.org/copyleft/gpl.html
18 */
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>
25
26#include <mach/platform.h>
27#include <mach/stmp3xxx.h>
28#include <mach/regs-rtc.h>
29
30struct stmp3xxx_rtc_data {
31 struct rtc_device *rtc;
32 unsigned irq_count;
33 void __iomem *io;
34 int irq_alarm, irq_1msec;
35};
36
37static void stmp3xxx_wait_time(struct stmp3xxx_rtc_data *rtc_data)
38{
39 /*
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
43 */
44 while (__raw_readl(rtc_data->io + HW_RTC_STAT) &
45 BF(0x80, RTC_STAT_STALE_REGS))
46 cpu_relax();
47}
48
49/* Time read/write */
50static int stmp3xxx_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
51{
52 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
53
54 stmp3xxx_wait_time(rtc_data);
55 rtc_time_to_tm(__raw_readl(rtc_data->io + HW_RTC_SECONDS), rtc_tm);
56 return 0;
57}
58
59static int stmp3xxx_rtc_set_mmss(struct device *dev, unsigned long t)
60{
61 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
62
63 __raw_writel(t, rtc_data->io + HW_RTC_SECONDS);
64 stmp3xxx_wait_time(rtc_data);
65 return 0;
66}
67
68/* interrupt(s) handler */
69static irqreturn_t stmp3xxx_rtc_interrupt(int irq, void *dev_id)
70{
71 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev_id);
72 u32 status;
73 u32 events = 0;
74
75 status = __raw_readl(rtc_data->io + HW_RTC_CTRL) &
76 (BM_RTC_CTRL_ALARM_IRQ | BM_RTC_CTRL_ONEMSEC_IRQ);
77
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;
82 }
83
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;
90 }
91 }
92
93 if (events)
94 rtc_update_irq(rtc_data->rtc, 1, events);
95
96 return IRQ_HANDLED;
97}
98
99static int stmp3xxx_alarm_irq_enable(struct device *dev, unsigned int enabled)
100{
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;
104
105 if (enabled) {
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);
109 } else {
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);
113 }
114 return 0;
115}
116
117static int stmp3xxx_update_irq_enable(struct device *dev, unsigned int enabled)
118{
119 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
120
121 if (enabled)
122 stmp3xxx_setl(BM_RTC_CTRL_ONEMSEC_IRQ_EN,
123 rtc_data->io + HW_RTC_CTRL);
124 else
125 stmp3xxx_clearl(BM_RTC_CTRL_ONEMSEC_IRQ_EN,
126 rtc_data->io + HW_RTC_CTRL);
127 return 0;
128}
129
130static int stmp3xxx_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
131{
132 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
133
134 rtc_time_to_tm(__raw_readl(rtc_data->io + HW_RTC_ALARM), &alm->time);
135 return 0;
136}
137
138static int stmp3xxx_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
139{
140 unsigned long t;
141 struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
142
143 rtc_tm_to_time(&alm->time, &t);
144 __raw_writel(t, rtc_data->io + HW_RTC_ALARM);
145 return 0;
146}
147
148static struct rtc_class_ops stmp3xxx_rtc_ops = {
149 .alarm_irq_enable =
150 stmp3xxx_alarm_irq_enable,
151 .update_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,
157};
158
159static int stmp3xxx_rtc_remove(struct platform_device *pdev)
160{
161 struct stmp3xxx_rtc_data *rtc_data = platform_get_drvdata(pdev);
162
163 if (!rtc_data)
164 return 0;
165
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);
172 kfree(rtc_data);
173
174 return 0;
175}
176
177static int stmp3xxx_rtc_probe(struct platform_device *pdev)
178{
179 struct stmp3xxx_rtc_data *rtc_data;
180 struct resource *r;
181 int err;
182
183 rtc_data = kzalloc(sizeof *rtc_data, GFP_KERNEL);
184 if (!rtc_data)
185 return -ENOMEM;
186
187 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
188 if (!r) {
189 dev_err(&pdev->dev, "failed to get resource\n");
190 err = -ENXIO;
191 goto out_free;
192 }
193
194 rtc_data->io = ioremap(r->start, resource_size(r));
195 if (!rtc_data->io) {
196 dev_err(&pdev->dev, "ioremap failed\n");
197 err = -EIO;
198 goto out_free;
199 }
200
201 rtc_data->irq_alarm = platform_get_irq(pdev, 0);
202 rtc_data->irq_1msec = platform_get_irq(pdev, 1);
203
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");
207 err = -ENODEV;
208 goto out_remap;
209 }
210
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);
220 goto out_remap;
221 }
222
223 rtc_data->irq_count = 0;
224 err = request_irq(rtc_data->irq_alarm, stmp3xxx_rtc_interrupt,
225 IRQF_DISABLED, "RTC alarm", &pdev->dev);
226 if (err) {
227 dev_err(&pdev->dev, "Cannot claim IRQ%d\n",
228 rtc_data->irq_alarm);
229 goto out_irq_alarm;
230 }
231 err = request_irq(rtc_data->irq_1msec, stmp3xxx_rtc_interrupt,
232 IRQF_DISABLED, "RTC tick", &pdev->dev);
233 if (err) {
234 dev_err(&pdev->dev, "Cannot claim IRQ%d\n",
235 rtc_data->irq_1msec);
236 goto out_irq1;
237 }
238
239 platform_set_drvdata(pdev, rtc_data);
240
241 return 0;
242
243out_irq1:
244 free_irq(rtc_data->irq_alarm, &pdev->dev);
245out_irq_alarm:
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);
249out_remap:
250 iounmap(rtc_data->io);
251out_free:
252 kfree(rtc_data);
253 return err;
254}
255
256#ifdef CONFIG_PM
257static int stmp3xxx_rtc_suspend(struct platform_device *dev, pm_message_t state)
258{
259 return 0;
260}
261
262static int stmp3xxx_rtc_resume(struct platform_device *dev)
263{
264 struct stmp3xxx_rtc_data *rtc_data = platform_get_drvdata(dev);
265
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);
271 return 0;
272}
273#else
274#define stmp3xxx_rtc_suspend NULL
275#define stmp3xxx_rtc_resume NULL
276#endif
277
278static 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,
283 .driver = {
284 .name = "stmp3xxx-rtc",
285 .owner = THIS_MODULE,
286 },
287};
288
289static int __init stmp3xxx_rtc_init(void)
290{
291 return platform_driver_register(&stmp3xxx_rtcdrv);
292}
293
294static void __exit stmp3xxx_rtc_exit(void)
295{
296 platform_driver_unregister(&stmp3xxx_rtcdrv);
297}
298
299module_init(stmp3xxx_rtc_init);
300module_exit(stmp3xxx_rtc_exit);
301
302MODULE_DESCRIPTION("STMP3xxx RTC Driver");
303MODULE_AUTHOR("dmitry pervushin <dpervushin@embeddedalley.com>");
304MODULE_LICENSE("GPL");