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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * An rtc driver for the Dallas DS1553
4 *
5 * Copyright (C) 2006 Atsushi Nemoto <anemo@mba.ocn.ne.jp>
6 */
7
8#include <linux/bcd.h>
9#include <linux/init.h>
10#include <linux/kernel.h>
11#include <linux/gfp.h>
12#include <linux/delay.h>
13#include <linux/jiffies.h>
14#include <linux/interrupt.h>
15#include <linux/rtc.h>
16#include <linux/platform_device.h>
17#include <linux/io.h>
18#include <linux/module.h>
19
20#define RTC_REG_SIZE 0x2000
21#define RTC_OFFSET 0x1ff0
22
23#define RTC_FLAGS (RTC_OFFSET + 0)
24#define RTC_SECONDS_ALARM (RTC_OFFSET + 2)
25#define RTC_MINUTES_ALARM (RTC_OFFSET + 3)
26#define RTC_HOURS_ALARM (RTC_OFFSET + 4)
27#define RTC_DATE_ALARM (RTC_OFFSET + 5)
28#define RTC_INTERRUPTS (RTC_OFFSET + 6)
29#define RTC_WATCHDOG (RTC_OFFSET + 7)
30#define RTC_CONTROL (RTC_OFFSET + 8)
31#define RTC_CENTURY (RTC_OFFSET + 8)
32#define RTC_SECONDS (RTC_OFFSET + 9)
33#define RTC_MINUTES (RTC_OFFSET + 10)
34#define RTC_HOURS (RTC_OFFSET + 11)
35#define RTC_DAY (RTC_OFFSET + 12)
36#define RTC_DATE (RTC_OFFSET + 13)
37#define RTC_MONTH (RTC_OFFSET + 14)
38#define RTC_YEAR (RTC_OFFSET + 15)
39
40#define RTC_CENTURY_MASK 0x3f
41#define RTC_SECONDS_MASK 0x7f
42#define RTC_DAY_MASK 0x07
43
44/* Bits in the Control/Century register */
45#define RTC_WRITE 0x80
46#define RTC_READ 0x40
47
48/* Bits in the Seconds register */
49#define RTC_STOP 0x80
50
51/* Bits in the Flags register */
52#define RTC_FLAGS_AF 0x40
53#define RTC_FLAGS_BLF 0x10
54
55/* Bits in the Interrupts register */
56#define RTC_INTS_AE 0x80
57
58struct rtc_plat_data {
59 struct rtc_device *rtc;
60 void __iomem *ioaddr;
61 unsigned long last_jiffies;
62 int irq;
63 unsigned int irqen;
64 int alrm_sec;
65 int alrm_min;
66 int alrm_hour;
67 int alrm_mday;
68 spinlock_t lock;
69};
70
71static int ds1553_rtc_set_time(struct device *dev, struct rtc_time *tm)
72{
73 struct rtc_plat_data *pdata = dev_get_drvdata(dev);
74 void __iomem *ioaddr = pdata->ioaddr;
75 u8 century;
76
77 century = bin2bcd((tm->tm_year + 1900) / 100);
78
79 writeb(RTC_WRITE, pdata->ioaddr + RTC_CONTROL);
80
81 writeb(bin2bcd(tm->tm_year % 100), ioaddr + RTC_YEAR);
82 writeb(bin2bcd(tm->tm_mon + 1), ioaddr + RTC_MONTH);
83 writeb(bin2bcd(tm->tm_wday) & RTC_DAY_MASK, ioaddr + RTC_DAY);
84 writeb(bin2bcd(tm->tm_mday), ioaddr + RTC_DATE);
85 writeb(bin2bcd(tm->tm_hour), ioaddr + RTC_HOURS);
86 writeb(bin2bcd(tm->tm_min), ioaddr + RTC_MINUTES);
87 writeb(bin2bcd(tm->tm_sec) & RTC_SECONDS_MASK, ioaddr + RTC_SECONDS);
88
89 /* RTC_CENTURY and RTC_CONTROL share same register */
90 writeb(RTC_WRITE | (century & RTC_CENTURY_MASK), ioaddr + RTC_CENTURY);
91 writeb(century & RTC_CENTURY_MASK, ioaddr + RTC_CONTROL);
92 return 0;
93}
94
95static int ds1553_rtc_read_time(struct device *dev, struct rtc_time *tm)
96{
97 struct rtc_plat_data *pdata = dev_get_drvdata(dev);
98 void __iomem *ioaddr = pdata->ioaddr;
99 unsigned int year, month, day, hour, minute, second, week;
100 unsigned int century;
101
102 /* give enough time to update RTC in case of continuous read */
103 if (pdata->last_jiffies == jiffies)
104 msleep(1);
105 pdata->last_jiffies = jiffies;
106 writeb(RTC_READ, ioaddr + RTC_CONTROL);
107 second = readb(ioaddr + RTC_SECONDS) & RTC_SECONDS_MASK;
108 minute = readb(ioaddr + RTC_MINUTES);
109 hour = readb(ioaddr + RTC_HOURS);
110 day = readb(ioaddr + RTC_DATE);
111 week = readb(ioaddr + RTC_DAY) & RTC_DAY_MASK;
112 month = readb(ioaddr + RTC_MONTH);
113 year = readb(ioaddr + RTC_YEAR);
114 century = readb(ioaddr + RTC_CENTURY) & RTC_CENTURY_MASK;
115 writeb(0, ioaddr + RTC_CONTROL);
116 tm->tm_sec = bcd2bin(second);
117 tm->tm_min = bcd2bin(minute);
118 tm->tm_hour = bcd2bin(hour);
119 tm->tm_mday = bcd2bin(day);
120 tm->tm_wday = bcd2bin(week);
121 tm->tm_mon = bcd2bin(month) - 1;
122 /* year is 1900 + tm->tm_year */
123 tm->tm_year = bcd2bin(year) + bcd2bin(century) * 100 - 1900;
124
125 return 0;
126}
127
128static void ds1553_rtc_update_alarm(struct rtc_plat_data *pdata)
129{
130 void __iomem *ioaddr = pdata->ioaddr;
131 unsigned long flags;
132
133 spin_lock_irqsave(&pdata->lock, flags);
134 writeb(pdata->alrm_mday < 0 || (pdata->irqen & RTC_UF) ?
135 0x80 : bin2bcd(pdata->alrm_mday),
136 ioaddr + RTC_DATE_ALARM);
137 writeb(pdata->alrm_hour < 0 || (pdata->irqen & RTC_UF) ?
138 0x80 : bin2bcd(pdata->alrm_hour),
139 ioaddr + RTC_HOURS_ALARM);
140 writeb(pdata->alrm_min < 0 || (pdata->irqen & RTC_UF) ?
141 0x80 : bin2bcd(pdata->alrm_min),
142 ioaddr + RTC_MINUTES_ALARM);
143 writeb(pdata->alrm_sec < 0 || (pdata->irqen & RTC_UF) ?
144 0x80 : bin2bcd(pdata->alrm_sec),
145 ioaddr + RTC_SECONDS_ALARM);
146 writeb(pdata->irqen ? RTC_INTS_AE : 0, ioaddr + RTC_INTERRUPTS);
147 readb(ioaddr + RTC_FLAGS); /* clear interrupts */
148 spin_unlock_irqrestore(&pdata->lock, flags);
149}
150
151static int ds1553_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
152{
153 struct rtc_plat_data *pdata = dev_get_drvdata(dev);
154
155 if (pdata->irq <= 0)
156 return -EINVAL;
157 pdata->alrm_mday = alrm->time.tm_mday;
158 pdata->alrm_hour = alrm->time.tm_hour;
159 pdata->alrm_min = alrm->time.tm_min;
160 pdata->alrm_sec = alrm->time.tm_sec;
161 if (alrm->enabled)
162 pdata->irqen |= RTC_AF;
163 ds1553_rtc_update_alarm(pdata);
164 return 0;
165}
166
167static int ds1553_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
168{
169 struct rtc_plat_data *pdata = dev_get_drvdata(dev);
170
171 if (pdata->irq <= 0)
172 return -EINVAL;
173 alrm->time.tm_mday = pdata->alrm_mday < 0 ? 0 : pdata->alrm_mday;
174 alrm->time.tm_hour = pdata->alrm_hour < 0 ? 0 : pdata->alrm_hour;
175 alrm->time.tm_min = pdata->alrm_min < 0 ? 0 : pdata->alrm_min;
176 alrm->time.tm_sec = pdata->alrm_sec < 0 ? 0 : pdata->alrm_sec;
177 alrm->enabled = (pdata->irqen & RTC_AF) ? 1 : 0;
178 return 0;
179}
180
181static irqreturn_t ds1553_rtc_interrupt(int irq, void *dev_id)
182{
183 struct platform_device *pdev = dev_id;
184 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
185 void __iomem *ioaddr = pdata->ioaddr;
186 unsigned long events = 0;
187
188 spin_lock(&pdata->lock);
189 /* read and clear interrupt */
190 if (readb(ioaddr + RTC_FLAGS) & RTC_FLAGS_AF) {
191 events = RTC_IRQF;
192 if (readb(ioaddr + RTC_SECONDS_ALARM) & 0x80)
193 events |= RTC_UF;
194 else
195 events |= RTC_AF;
196 rtc_update_irq(pdata->rtc, 1, events);
197 }
198 spin_unlock(&pdata->lock);
199 return events ? IRQ_HANDLED : IRQ_NONE;
200}
201
202static int ds1553_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
203{
204 struct rtc_plat_data *pdata = dev_get_drvdata(dev);
205
206 if (pdata->irq <= 0)
207 return -EINVAL;
208 if (enabled)
209 pdata->irqen |= RTC_AF;
210 else
211 pdata->irqen &= ~RTC_AF;
212 ds1553_rtc_update_alarm(pdata);
213 return 0;
214}
215
216static const struct rtc_class_ops ds1553_rtc_ops = {
217 .read_time = ds1553_rtc_read_time,
218 .set_time = ds1553_rtc_set_time,
219 .read_alarm = ds1553_rtc_read_alarm,
220 .set_alarm = ds1553_rtc_set_alarm,
221 .alarm_irq_enable = ds1553_rtc_alarm_irq_enable,
222};
223
224static int ds1553_nvram_read(void *priv, unsigned int pos, void *val,
225 size_t bytes)
226{
227 struct platform_device *pdev = priv;
228 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
229 void __iomem *ioaddr = pdata->ioaddr;
230 u8 *buf = val;
231
232 for (; bytes; bytes--)
233 *buf++ = readb(ioaddr + pos++);
234 return 0;
235}
236
237static int ds1553_nvram_write(void *priv, unsigned int pos, void *val,
238 size_t bytes)
239{
240 struct platform_device *pdev = priv;
241 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
242 void __iomem *ioaddr = pdata->ioaddr;
243 u8 *buf = val;
244
245 for (; bytes; bytes--)
246 writeb(*buf++, ioaddr + pos++);
247 return 0;
248}
249
250static int ds1553_rtc_probe(struct platform_device *pdev)
251{
252 unsigned int cen, sec;
253 struct rtc_plat_data *pdata;
254 void __iomem *ioaddr;
255 int ret = 0;
256 struct nvmem_config nvmem_cfg = {
257 .name = "ds1553_nvram",
258 .word_size = 1,
259 .stride = 1,
260 .size = RTC_OFFSET,
261 .reg_read = ds1553_nvram_read,
262 .reg_write = ds1553_nvram_write,
263 .priv = pdev,
264 };
265
266 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
267 if (!pdata)
268 return -ENOMEM;
269
270 ioaddr = devm_platform_ioremap_resource(pdev, 0);
271 if (IS_ERR(ioaddr))
272 return PTR_ERR(ioaddr);
273 pdata->ioaddr = ioaddr;
274 pdata->irq = platform_get_irq(pdev, 0);
275
276 /* turn RTC on if it was not on */
277 sec = readb(ioaddr + RTC_SECONDS);
278 if (sec & RTC_STOP) {
279 sec &= RTC_SECONDS_MASK;
280 cen = readb(ioaddr + RTC_CENTURY) & RTC_CENTURY_MASK;
281 writeb(RTC_WRITE, ioaddr + RTC_CONTROL);
282 writeb(sec, ioaddr + RTC_SECONDS);
283 writeb(cen & RTC_CENTURY_MASK, ioaddr + RTC_CONTROL);
284 }
285 if (readb(ioaddr + RTC_FLAGS) & RTC_FLAGS_BLF)
286 dev_warn(&pdev->dev, "voltage-low detected.\n");
287
288 spin_lock_init(&pdata->lock);
289 pdata->last_jiffies = jiffies;
290 platform_set_drvdata(pdev, pdata);
291
292 pdata->rtc = devm_rtc_allocate_device(&pdev->dev);
293 if (IS_ERR(pdata->rtc))
294 return PTR_ERR(pdata->rtc);
295
296 pdata->rtc->ops = &ds1553_rtc_ops;
297
298 ret = devm_rtc_register_device(pdata->rtc);
299 if (ret)
300 return ret;
301
302 if (pdata->irq > 0) {
303 writeb(0, ioaddr + RTC_INTERRUPTS);
304 if (devm_request_irq(&pdev->dev, pdata->irq,
305 ds1553_rtc_interrupt,
306 0, pdev->name, pdev) < 0) {
307 dev_warn(&pdev->dev, "interrupt not available.\n");
308 pdata->irq = 0;
309 }
310 }
311
312 devm_rtc_nvmem_register(pdata->rtc, &nvmem_cfg);
313
314 return 0;
315}
316
317/* work with hotplug and coldplug */
318MODULE_ALIAS("platform:rtc-ds1553");
319
320static struct platform_driver ds1553_rtc_driver = {
321 .probe = ds1553_rtc_probe,
322 .driver = {
323 .name = "rtc-ds1553",
324 },
325};
326
327module_platform_driver(ds1553_rtc_driver);
328
329MODULE_AUTHOR("Atsushi Nemoto <anemo@mba.ocn.ne.jp>");
330MODULE_DESCRIPTION("Dallas DS1553 RTC driver");
331MODULE_LICENSE("GPL");
1/*
2 * An rtc driver for the Dallas DS1553
3 *
4 * Copyright (C) 2006 Atsushi Nemoto <anemo@mba.ocn.ne.jp>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11#include <linux/bcd.h>
12#include <linux/init.h>
13#include <linux/kernel.h>
14#include <linux/gfp.h>
15#include <linux/delay.h>
16#include <linux/jiffies.h>
17#include <linux/interrupt.h>
18#include <linux/rtc.h>
19#include <linux/platform_device.h>
20#include <linux/io.h>
21#include <linux/module.h>
22
23#define RTC_REG_SIZE 0x2000
24#define RTC_OFFSET 0x1ff0
25
26#define RTC_FLAGS (RTC_OFFSET + 0)
27#define RTC_SECONDS_ALARM (RTC_OFFSET + 2)
28#define RTC_MINUTES_ALARM (RTC_OFFSET + 3)
29#define RTC_HOURS_ALARM (RTC_OFFSET + 4)
30#define RTC_DATE_ALARM (RTC_OFFSET + 5)
31#define RTC_INTERRUPTS (RTC_OFFSET + 6)
32#define RTC_WATCHDOG (RTC_OFFSET + 7)
33#define RTC_CONTROL (RTC_OFFSET + 8)
34#define RTC_CENTURY (RTC_OFFSET + 8)
35#define RTC_SECONDS (RTC_OFFSET + 9)
36#define RTC_MINUTES (RTC_OFFSET + 10)
37#define RTC_HOURS (RTC_OFFSET + 11)
38#define RTC_DAY (RTC_OFFSET + 12)
39#define RTC_DATE (RTC_OFFSET + 13)
40#define RTC_MONTH (RTC_OFFSET + 14)
41#define RTC_YEAR (RTC_OFFSET + 15)
42
43#define RTC_CENTURY_MASK 0x3f
44#define RTC_SECONDS_MASK 0x7f
45#define RTC_DAY_MASK 0x07
46
47/* Bits in the Control/Century register */
48#define RTC_WRITE 0x80
49#define RTC_READ 0x40
50
51/* Bits in the Seconds register */
52#define RTC_STOP 0x80
53
54/* Bits in the Flags register */
55#define RTC_FLAGS_AF 0x40
56#define RTC_FLAGS_BLF 0x10
57
58/* Bits in the Interrupts register */
59#define RTC_INTS_AE 0x80
60
61struct rtc_plat_data {
62 struct rtc_device *rtc;
63 void __iomem *ioaddr;
64 unsigned long last_jiffies;
65 int irq;
66 unsigned int irqen;
67 int alrm_sec;
68 int alrm_min;
69 int alrm_hour;
70 int alrm_mday;
71 spinlock_t lock;
72};
73
74static int ds1553_rtc_set_time(struct device *dev, struct rtc_time *tm)
75{
76 struct platform_device *pdev = to_platform_device(dev);
77 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
78 void __iomem *ioaddr = pdata->ioaddr;
79 u8 century;
80
81 century = bin2bcd((tm->tm_year + 1900) / 100);
82
83 writeb(RTC_WRITE, pdata->ioaddr + RTC_CONTROL);
84
85 writeb(bin2bcd(tm->tm_year % 100), ioaddr + RTC_YEAR);
86 writeb(bin2bcd(tm->tm_mon + 1), ioaddr + RTC_MONTH);
87 writeb(bin2bcd(tm->tm_wday) & RTC_DAY_MASK, ioaddr + RTC_DAY);
88 writeb(bin2bcd(tm->tm_mday), ioaddr + RTC_DATE);
89 writeb(bin2bcd(tm->tm_hour), ioaddr + RTC_HOURS);
90 writeb(bin2bcd(tm->tm_min), ioaddr + RTC_MINUTES);
91 writeb(bin2bcd(tm->tm_sec) & RTC_SECONDS_MASK, ioaddr + RTC_SECONDS);
92
93 /* RTC_CENTURY and RTC_CONTROL share same register */
94 writeb(RTC_WRITE | (century & RTC_CENTURY_MASK), ioaddr + RTC_CENTURY);
95 writeb(century & RTC_CENTURY_MASK, ioaddr + RTC_CONTROL);
96 return 0;
97}
98
99static int ds1553_rtc_read_time(struct device *dev, struct rtc_time *tm)
100{
101 struct platform_device *pdev = to_platform_device(dev);
102 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
103 void __iomem *ioaddr = pdata->ioaddr;
104 unsigned int year, month, day, hour, minute, second, week;
105 unsigned int century;
106
107 /* give enough time to update RTC in case of continuous read */
108 if (pdata->last_jiffies == jiffies)
109 msleep(1);
110 pdata->last_jiffies = jiffies;
111 writeb(RTC_READ, ioaddr + RTC_CONTROL);
112 second = readb(ioaddr + RTC_SECONDS) & RTC_SECONDS_MASK;
113 minute = readb(ioaddr + RTC_MINUTES);
114 hour = readb(ioaddr + RTC_HOURS);
115 day = readb(ioaddr + RTC_DATE);
116 week = readb(ioaddr + RTC_DAY) & RTC_DAY_MASK;
117 month = readb(ioaddr + RTC_MONTH);
118 year = readb(ioaddr + RTC_YEAR);
119 century = readb(ioaddr + RTC_CENTURY) & RTC_CENTURY_MASK;
120 writeb(0, ioaddr + RTC_CONTROL);
121 tm->tm_sec = bcd2bin(second);
122 tm->tm_min = bcd2bin(minute);
123 tm->tm_hour = bcd2bin(hour);
124 tm->tm_mday = bcd2bin(day);
125 tm->tm_wday = bcd2bin(week);
126 tm->tm_mon = bcd2bin(month) - 1;
127 /* year is 1900 + tm->tm_year */
128 tm->tm_year = bcd2bin(year) + bcd2bin(century) * 100 - 1900;
129
130 if (rtc_valid_tm(tm) < 0) {
131 dev_err(dev, "retrieved date/time is not valid.\n");
132 rtc_time_to_tm(0, tm);
133 }
134 return 0;
135}
136
137static void ds1553_rtc_update_alarm(struct rtc_plat_data *pdata)
138{
139 void __iomem *ioaddr = pdata->ioaddr;
140 unsigned long flags;
141
142 spin_lock_irqsave(&pdata->lock, flags);
143 writeb(pdata->alrm_mday < 0 || (pdata->irqen & RTC_UF) ?
144 0x80 : bin2bcd(pdata->alrm_mday),
145 ioaddr + RTC_DATE_ALARM);
146 writeb(pdata->alrm_hour < 0 || (pdata->irqen & RTC_UF) ?
147 0x80 : bin2bcd(pdata->alrm_hour),
148 ioaddr + RTC_HOURS_ALARM);
149 writeb(pdata->alrm_min < 0 || (pdata->irqen & RTC_UF) ?
150 0x80 : bin2bcd(pdata->alrm_min),
151 ioaddr + RTC_MINUTES_ALARM);
152 writeb(pdata->alrm_sec < 0 || (pdata->irqen & RTC_UF) ?
153 0x80 : bin2bcd(pdata->alrm_sec),
154 ioaddr + RTC_SECONDS_ALARM);
155 writeb(pdata->irqen ? RTC_INTS_AE : 0, ioaddr + RTC_INTERRUPTS);
156 readb(ioaddr + RTC_FLAGS); /* clear interrupts */
157 spin_unlock_irqrestore(&pdata->lock, flags);
158}
159
160static int ds1553_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
161{
162 struct platform_device *pdev = to_platform_device(dev);
163 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
164
165 if (pdata->irq <= 0)
166 return -EINVAL;
167 pdata->alrm_mday = alrm->time.tm_mday;
168 pdata->alrm_hour = alrm->time.tm_hour;
169 pdata->alrm_min = alrm->time.tm_min;
170 pdata->alrm_sec = alrm->time.tm_sec;
171 if (alrm->enabled)
172 pdata->irqen |= RTC_AF;
173 ds1553_rtc_update_alarm(pdata);
174 return 0;
175}
176
177static int ds1553_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
178{
179 struct platform_device *pdev = to_platform_device(dev);
180 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
181
182 if (pdata->irq <= 0)
183 return -EINVAL;
184 alrm->time.tm_mday = pdata->alrm_mday < 0 ? 0 : pdata->alrm_mday;
185 alrm->time.tm_hour = pdata->alrm_hour < 0 ? 0 : pdata->alrm_hour;
186 alrm->time.tm_min = pdata->alrm_min < 0 ? 0 : pdata->alrm_min;
187 alrm->time.tm_sec = pdata->alrm_sec < 0 ? 0 : pdata->alrm_sec;
188 alrm->enabled = (pdata->irqen & RTC_AF) ? 1 : 0;
189 return 0;
190}
191
192static irqreturn_t ds1553_rtc_interrupt(int irq, void *dev_id)
193{
194 struct platform_device *pdev = dev_id;
195 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
196 void __iomem *ioaddr = pdata->ioaddr;
197 unsigned long events = 0;
198
199 spin_lock(&pdata->lock);
200 /* read and clear interrupt */
201 if (readb(ioaddr + RTC_FLAGS) & RTC_FLAGS_AF) {
202 events = RTC_IRQF;
203 if (readb(ioaddr + RTC_SECONDS_ALARM) & 0x80)
204 events |= RTC_UF;
205 else
206 events |= RTC_AF;
207 rtc_update_irq(pdata->rtc, 1, events);
208 }
209 spin_unlock(&pdata->lock);
210 return events ? IRQ_HANDLED : IRQ_NONE;
211}
212
213static int ds1553_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
214{
215 struct platform_device *pdev = to_platform_device(dev);
216 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
217
218 if (pdata->irq <= 0)
219 return -EINVAL;
220 if (enabled)
221 pdata->irqen |= RTC_AF;
222 else
223 pdata->irqen &= ~RTC_AF;
224 ds1553_rtc_update_alarm(pdata);
225 return 0;
226}
227
228static const struct rtc_class_ops ds1553_rtc_ops = {
229 .read_time = ds1553_rtc_read_time,
230 .set_time = ds1553_rtc_set_time,
231 .read_alarm = ds1553_rtc_read_alarm,
232 .set_alarm = ds1553_rtc_set_alarm,
233 .alarm_irq_enable = ds1553_rtc_alarm_irq_enable,
234};
235
236static ssize_t ds1553_nvram_read(struct file *filp, struct kobject *kobj,
237 struct bin_attribute *bin_attr,
238 char *buf, loff_t pos, size_t size)
239{
240 struct device *dev = container_of(kobj, struct device, kobj);
241 struct platform_device *pdev = to_platform_device(dev);
242 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
243 void __iomem *ioaddr = pdata->ioaddr;
244 ssize_t count;
245
246 for (count = 0; count < size; count++)
247 *buf++ = readb(ioaddr + pos++);
248 return count;
249}
250
251static ssize_t ds1553_nvram_write(struct file *filp, struct kobject *kobj,
252 struct bin_attribute *bin_attr,
253 char *buf, loff_t pos, size_t size)
254{
255 struct device *dev = container_of(kobj, struct device, kobj);
256 struct platform_device *pdev = to_platform_device(dev);
257 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
258 void __iomem *ioaddr = pdata->ioaddr;
259 ssize_t count;
260
261 for (count = 0; count < size; count++)
262 writeb(*buf++, ioaddr + pos++);
263 return count;
264}
265
266static struct bin_attribute ds1553_nvram_attr = {
267 .attr = {
268 .name = "nvram",
269 .mode = S_IRUGO | S_IWUSR,
270 },
271 .size = RTC_OFFSET,
272 .read = ds1553_nvram_read,
273 .write = ds1553_nvram_write,
274};
275
276static int ds1553_rtc_probe(struct platform_device *pdev)
277{
278 struct resource *res;
279 unsigned int cen, sec;
280 struct rtc_plat_data *pdata;
281 void __iomem *ioaddr;
282 int ret = 0;
283
284 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
285 if (!pdata)
286 return -ENOMEM;
287
288 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
289 ioaddr = devm_ioremap_resource(&pdev->dev, res);
290 if (IS_ERR(ioaddr))
291 return PTR_ERR(ioaddr);
292 pdata->ioaddr = ioaddr;
293 pdata->irq = platform_get_irq(pdev, 0);
294
295 /* turn RTC on if it was not on */
296 sec = readb(ioaddr + RTC_SECONDS);
297 if (sec & RTC_STOP) {
298 sec &= RTC_SECONDS_MASK;
299 cen = readb(ioaddr + RTC_CENTURY) & RTC_CENTURY_MASK;
300 writeb(RTC_WRITE, ioaddr + RTC_CONTROL);
301 writeb(sec, ioaddr + RTC_SECONDS);
302 writeb(cen & RTC_CENTURY_MASK, ioaddr + RTC_CONTROL);
303 }
304 if (readb(ioaddr + RTC_FLAGS) & RTC_FLAGS_BLF)
305 dev_warn(&pdev->dev, "voltage-low detected.\n");
306
307 spin_lock_init(&pdata->lock);
308 pdata->last_jiffies = jiffies;
309 platform_set_drvdata(pdev, pdata);
310
311 pdata->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
312 &ds1553_rtc_ops, THIS_MODULE);
313 if (IS_ERR(pdata->rtc))
314 return PTR_ERR(pdata->rtc);
315
316 if (pdata->irq > 0) {
317 writeb(0, ioaddr + RTC_INTERRUPTS);
318 if (devm_request_irq(&pdev->dev, pdata->irq,
319 ds1553_rtc_interrupt,
320 0, pdev->name, pdev) < 0) {
321 dev_warn(&pdev->dev, "interrupt not available.\n");
322 pdata->irq = 0;
323 }
324 }
325
326 ret = sysfs_create_bin_file(&pdev->dev.kobj, &ds1553_nvram_attr);
327 if (ret)
328 dev_err(&pdev->dev, "unable to create sysfs file: %s\n",
329 ds1553_nvram_attr.attr.name);
330
331 return 0;
332}
333
334static int ds1553_rtc_remove(struct platform_device *pdev)
335{
336 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
337
338 sysfs_remove_bin_file(&pdev->dev.kobj, &ds1553_nvram_attr);
339 if (pdata->irq > 0)
340 writeb(0, pdata->ioaddr + RTC_INTERRUPTS);
341 return 0;
342}
343
344/* work with hotplug and coldplug */
345MODULE_ALIAS("platform:rtc-ds1553");
346
347static struct platform_driver ds1553_rtc_driver = {
348 .probe = ds1553_rtc_probe,
349 .remove = ds1553_rtc_remove,
350 .driver = {
351 .name = "rtc-ds1553",
352 },
353};
354
355module_platform_driver(ds1553_rtc_driver);
356
357MODULE_AUTHOR("Atsushi Nemoto <anemo@mba.ocn.ne.jp>");
358MODULE_DESCRIPTION("Dallas DS1553 RTC driver");
359MODULE_LICENSE("GPL");