ARM: tegra30: pm: flush L1 data before exit coherency on secondary CPU
[linux-2.6.git] / drivers / rtc / rtc-stmp3xxx.c
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  * Copyright 2011 Wolfram Sang, Pengutronix e.K.
10  */
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>
22 #include <linux/io.h>
23 #include <linux/init.h>
24 #include <linux/platform_device.h>
25 #include <linux/interrupt.h>
26 #include <linux/rtc.h>
27 #include <linux/slab.h>
28
29 #include <mach/common.h>
30
31 #define STMP3XXX_RTC_CTRL                       0x0
32 #define STMP3XXX_RTC_CTRL_SET                   0x4
33 #define STMP3XXX_RTC_CTRL_CLR                   0x8
34 #define STMP3XXX_RTC_CTRL_ALARM_IRQ_EN          0x00000001
35 #define STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN        0x00000002
36 #define STMP3XXX_RTC_CTRL_ALARM_IRQ             0x00000004
37
38 #define STMP3XXX_RTC_STAT                       0x10
39 #define STMP3XXX_RTC_STAT_STALE_SHIFT           16
40 #define STMP3XXX_RTC_STAT_RTC_PRESENT           0x80000000
41
42 #define STMP3XXX_RTC_SECONDS                    0x30
43
44 #define STMP3XXX_RTC_ALARM                      0x40
45
46 #define STMP3XXX_RTC_PERSISTENT0                0x60
47 #define STMP3XXX_RTC_PERSISTENT0_SET            0x64
48 #define STMP3XXX_RTC_PERSISTENT0_CLR            0x68
49 #define STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN  0x00000002
50 #define STMP3XXX_RTC_PERSISTENT0_ALARM_EN       0x00000004
51 #define STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE     0x00000080
52
53 struct stmp3xxx_rtc_data {
54         struct rtc_device *rtc;
55         void __iomem *io;
56         int irq_alarm;
57 };
58
59 static void stmp3xxx_wait_time(struct stmp3xxx_rtc_data *rtc_data)
60 {
61         /*
62          * The datasheet doesn't say which way round the
63          * NEW_REGS/STALE_REGS bitfields go. In fact it's 0x1=P0,
64          * 0x2=P1, .., 0x20=P5, 0x40=ALARM, 0x80=SECONDS
65          */
66         while (readl(rtc_data->io + STMP3XXX_RTC_STAT) &
67                         (0x80 << STMP3XXX_RTC_STAT_STALE_SHIFT))
68                 cpu_relax();
69 }
70
71 /* Time read/write */
72 static int stmp3xxx_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
73 {
74         struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
75
76         stmp3xxx_wait_time(rtc_data);
77         rtc_time_to_tm(readl(rtc_data->io + STMP3XXX_RTC_SECONDS), rtc_tm);
78         return 0;
79 }
80
81 static int stmp3xxx_rtc_set_mmss(struct device *dev, unsigned long t)
82 {
83         struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
84
85         writel(t, rtc_data->io + STMP3XXX_RTC_SECONDS);
86         stmp3xxx_wait_time(rtc_data);
87         return 0;
88 }
89
90 /* interrupt(s) handler */
91 static irqreturn_t stmp3xxx_rtc_interrupt(int irq, void *dev_id)
92 {
93         struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev_id);
94         u32 status = readl(rtc_data->io + STMP3XXX_RTC_CTRL);
95
96         if (status & STMP3XXX_RTC_CTRL_ALARM_IRQ) {
97                 writel(STMP3XXX_RTC_CTRL_ALARM_IRQ,
98                                 rtc_data->io + STMP3XXX_RTC_CTRL_CLR);
99                 rtc_update_irq(rtc_data->rtc, 1, RTC_AF | RTC_IRQF);
100                 return IRQ_HANDLED;
101         }
102
103         return IRQ_NONE;
104 }
105
106 static int stmp3xxx_alarm_irq_enable(struct device *dev, unsigned int enabled)
107 {
108         struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
109
110         if (enabled) {
111                 writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
112                                 STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN,
113                                 rtc_data->io + STMP3XXX_RTC_PERSISTENT0_SET);
114                 writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
115                                 rtc_data->io + STMP3XXX_RTC_CTRL_SET);
116         } else {
117                 writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
118                                 STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN,
119                                 rtc_data->io + STMP3XXX_RTC_PERSISTENT0_CLR);
120                 writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
121                                 rtc_data->io + STMP3XXX_RTC_CTRL_CLR);
122         }
123         return 0;
124 }
125
126 static int stmp3xxx_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
127 {
128         struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
129
130         rtc_time_to_tm(readl(rtc_data->io + STMP3XXX_RTC_ALARM), &alm->time);
131         return 0;
132 }
133
134 static int stmp3xxx_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
135 {
136         unsigned long t;
137         struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev);
138
139         rtc_tm_to_time(&alm->time, &t);
140         writel(t, rtc_data->io + STMP3XXX_RTC_ALARM);
141
142         stmp3xxx_alarm_irq_enable(dev, alm->enabled);
143
144         return 0;
145 }
146
147 static struct rtc_class_ops stmp3xxx_rtc_ops = {
148         .alarm_irq_enable =
149                           stmp3xxx_alarm_irq_enable,
150         .read_time      = stmp3xxx_rtc_gettime,
151         .set_mmss       = stmp3xxx_rtc_set_mmss,
152         .read_alarm     = stmp3xxx_rtc_read_alarm,
153         .set_alarm      = stmp3xxx_rtc_set_alarm,
154 };
155
156 static int stmp3xxx_rtc_remove(struct platform_device *pdev)
157 {
158         struct stmp3xxx_rtc_data *rtc_data = platform_get_drvdata(pdev);
159
160         if (!rtc_data)
161                 return 0;
162
163         writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
164                         rtc_data->io + STMP3XXX_RTC_CTRL_CLR);
165         free_irq(rtc_data->irq_alarm, &pdev->dev);
166         rtc_device_unregister(rtc_data->rtc);
167         platform_set_drvdata(pdev, NULL);
168         iounmap(rtc_data->io);
169         kfree(rtc_data);
170
171         return 0;
172 }
173
174 static int stmp3xxx_rtc_probe(struct platform_device *pdev)
175 {
176         struct stmp3xxx_rtc_data *rtc_data;
177         struct resource *r;
178         int err;
179
180         rtc_data = kzalloc(sizeof *rtc_data, GFP_KERNEL);
181         if (!rtc_data)
182                 return -ENOMEM;
183
184         r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
185         if (!r) {
186                 dev_err(&pdev->dev, "failed to get resource\n");
187                 err = -ENXIO;
188                 goto out_free;
189         }
190
191         rtc_data->io = ioremap(r->start, resource_size(r));
192         if (!rtc_data->io) {
193                 dev_err(&pdev->dev, "ioremap failed\n");
194                 err = -EIO;
195                 goto out_free;
196         }
197
198         rtc_data->irq_alarm = platform_get_irq(pdev, 0);
199
200         if (!(readl(STMP3XXX_RTC_STAT + rtc_data->io) &
201                         STMP3XXX_RTC_STAT_RTC_PRESENT)) {
202                 dev_err(&pdev->dev, "no device onboard\n");
203                 err = -ENODEV;
204                 goto out_remap;
205         }
206
207         platform_set_drvdata(pdev, rtc_data);
208
209         mxs_reset_block(rtc_data->io);
210         writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
211                         STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN |
212                         STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE,
213                         rtc_data->io + STMP3XXX_RTC_PERSISTENT0_CLR);
214
215         writel(STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN |
216                         STMP3XXX_RTC_CTRL_ALARM_IRQ_EN,
217                         rtc_data->io + STMP3XXX_RTC_CTRL_CLR);
218
219         rtc_data->rtc = rtc_device_register(pdev->name, &pdev->dev,
220                                 &stmp3xxx_rtc_ops, THIS_MODULE);
221         if (IS_ERR(rtc_data->rtc)) {
222                 err = PTR_ERR(rtc_data->rtc);
223                 goto out_remap;
224         }
225
226         err = request_irq(rtc_data->irq_alarm, stmp3xxx_rtc_interrupt, 0,
227                         "RTC alarm", &pdev->dev);
228         if (err) {
229                 dev_err(&pdev->dev, "Cannot claim IRQ%d\n",
230                         rtc_data->irq_alarm);
231                 goto out_irq_alarm;
232         }
233
234         return 0;
235
236 out_irq_alarm:
237         rtc_device_unregister(rtc_data->rtc);
238 out_remap:
239         platform_set_drvdata(pdev, NULL);
240         iounmap(rtc_data->io);
241 out_free:
242         kfree(rtc_data);
243         return err;
244 }
245
246 #ifdef CONFIG_PM
247 static int stmp3xxx_rtc_suspend(struct platform_device *dev, pm_message_t state)
248 {
249         return 0;
250 }
251
252 static int stmp3xxx_rtc_resume(struct platform_device *dev)
253 {
254         struct stmp3xxx_rtc_data *rtc_data = platform_get_drvdata(dev);
255
256         mxs_reset_block(rtc_data->io);
257         writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN |
258                         STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN |
259                         STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE,
260                         rtc_data->io + STMP3XXX_RTC_PERSISTENT0_CLR);
261         return 0;
262 }
263 #else
264 #define stmp3xxx_rtc_suspend    NULL
265 #define stmp3xxx_rtc_resume     NULL
266 #endif
267
268 static struct platform_driver stmp3xxx_rtcdrv = {
269         .probe          = stmp3xxx_rtc_probe,
270         .remove         = stmp3xxx_rtc_remove,
271         .suspend        = stmp3xxx_rtc_suspend,
272         .resume         = stmp3xxx_rtc_resume,
273         .driver         = {
274                 .name   = "stmp3xxx-rtc",
275                 .owner  = THIS_MODULE,
276         },
277 };
278
279 static int __init stmp3xxx_rtc_init(void)
280 {
281         return platform_driver_register(&stmp3xxx_rtcdrv);
282 }
283
284 static void __exit stmp3xxx_rtc_exit(void)
285 {
286         platform_driver_unregister(&stmp3xxx_rtcdrv);
287 }
288
289 module_init(stmp3xxx_rtc_init);
290 module_exit(stmp3xxx_rtc_exit);
291
292 MODULE_DESCRIPTION("STMP3xxx RTC Driver");
293 MODULE_AUTHOR("dmitry pervushin <dpervushin@embeddedalley.com> and "
294                 "Wolfram Sang <w.sang@pengutronix.de>");
295 MODULE_LICENSE("GPL");