projects/linux·blob master · refs

392 lines · 10.2 KiB

1/*
2 * Ricoh RS5C313 RTC device/driver
3 * Copyright (C) 2007 Nobuhiro Iwamatsu
4 *
5 * 2005-09-19 modified by kogiidena
6 *
7 * Based on the old drivers/char/rs5c313_rtc.c by:
8 * Copyright (C) 2000 Philipp Rumpf <[email protected]>
9 * Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka
10 *
11 * Based on code written by Paul Gortmaker.
12 * Copyright (C) 1996 Paul Gortmaker
13 *
14 * This file is subject to the terms and conditions of the GNU General Public
15 * License. See the file "COPYING" in the main directory of this archive
16 * for more details.
17 *
18 * Based on other minimal char device drivers, like Alan's
19 * watchdog, Ted's random, etc. etc.
20 *
21 * 1.07 Paul Gortmaker.
22 * 1.08 Miquel van Smoorenburg: disallow certain things on the
23 * DEC Alpha as the CMOS clock is also used for other things.
24 * 1.09 Nikita Schmidt: epoch support and some Alpha cleanup.
25 * 1.09a Pete Zaitcev: Sun SPARC
26 * 1.09b Jeff Garzik: Modularize, init cleanup
27 * 1.09c Jeff Garzik: SMP cleanup
28 * 1.10 Paul Barton-Davis: add support for async I/O
29 * 1.10a Andrea Arcangeli: Alpha updates
30 * 1.10b Andrew Morton: SMP lock fix
31 * 1.10c Cesar Barros: SMP locking fixes and cleanup
32 * 1.10d Paul Gortmaker: delete paranoia check in rtc_exit
33 * 1.10e Maciej W. Rozycki: Handle DECstation's year weirdness.
34 * 1.11 Takashi Iwai: Kernel access functions
35 * rtc_register/rtc_unregister/rtc_control
36 * 1.11a Daniele Bellucci: Audit create_proc_read_entry in rtc_init
37 * 1.12 Venkatesh Pallipadi: Hooks for emulating rtc on HPET base-timer
38 * CONFIG_HPET_EMULATE_RTC
39 * 1.13 Nobuhiro Iwamatsu: Update driver.
40 */
41
42#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
43
44#include <linux/module.h>
45#include <linux/err.h>
46#include <linux/rtc.h>
47#include <linux/platform_device.h>
48#include <linux/bcd.h>
49#include <linux/delay.h>
50#include <linux/io.h>
51
52#define DRV_NAME "rs5c313"
53
54#ifdef CONFIG_SH_LANDISK
55/*****************************************************/
56/* LANDISK dependence part of RS5C313 */
57/*****************************************************/
58
59#define SCSMR1 0xFFE00000
60#define SCSCR1 0xFFE00008
61#define SCSMR1_CA 0x80
62#define SCSCR1_CKE 0x03
63#define SCSPTR1 0xFFE0001C
64#define SCSPTR1_EIO 0x80
65#define SCSPTR1_SPB1IO 0x08
66#define SCSPTR1_SPB1DT 0x04
67#define SCSPTR1_SPB0IO 0x02
68#define SCSPTR1_SPB0DT 0x01
69
70#define SDA_OEN SCSPTR1_SPB1IO
71#define SDA SCSPTR1_SPB1DT
72#define SCL_OEN SCSPTR1_SPB0IO
73#define SCL SCSPTR1_SPB0DT
74
75/* RICOH RS5C313 CE port */
76#define RS5C313_CE 0xB0000003
77
78/* RICOH RS5C313 CE port bit */
79#define RS5C313_CE_RTCCE 0x02
80
81/* SCSPTR1 data */
82unsigned char scsptr1_data;
83
84#define RS5C313_CEENABLE __raw_writeb(RS5C313_CE_RTCCE, RS5C313_CE);
85#define RS5C313_CEDISABLE __raw_writeb(0x00, RS5C313_CE)
86#define RS5C313_MISCOP __raw_writeb(0x02, 0xB0000008)
87
88static void rs5c313_init_port(void)
89{
90 /* Set SCK as I/O port and Initialize SCSPTR1 data & I/O port. */
91 __raw_writeb(__raw_readb(SCSMR1) & ~SCSMR1_CA, SCSMR1);
92 __raw_writeb(__raw_readb(SCSCR1) & ~SCSCR1_CKE, SCSCR1);
93
94 /* And Initialize SCL for RS5C313 clock */
95 scsptr1_data = __raw_readb(SCSPTR1) | SCL; /* SCL:H */
96 __raw_writeb(scsptr1_data, SCSPTR1);
97 scsptr1_data = __raw_readb(SCSPTR1) | SCL_OEN; /* SCL output enable */
98 __raw_writeb(scsptr1_data, SCSPTR1);
99 RS5C313_CEDISABLE; /* CE:L */
100}
101
102static void rs5c313_write_data(unsigned char data)
103{
104 int i;
105
106 for (i = 0; i < 8; i++) {
107 /* SDA:Write Data */
108 scsptr1_data = (scsptr1_data & ~SDA) |
109 ((((0x80 >> i) & data) >> (7 - i)) << 2);
110 __raw_writeb(scsptr1_data, SCSPTR1);
111 if (i == 0) {
112 scsptr1_data |= SDA_OEN; /* SDA:output enable */
113 __raw_writeb(scsptr1_data, SCSPTR1);
114 }
115 ndelay(700);
116 scsptr1_data &= ~SCL; /* SCL:L */
117 __raw_writeb(scsptr1_data, SCSPTR1);
118 ndelay(700);
119 scsptr1_data |= SCL; /* SCL:H */
120 __raw_writeb(scsptr1_data, SCSPTR1);
121 }
122
123 scsptr1_data &= ~SDA_OEN; /* SDA:output disable */
124 __raw_writeb(scsptr1_data, SCSPTR1);
125}
126
127static unsigned char rs5c313_read_data(void)
128{
129 int i;
130 unsigned char data = 0;
131
132 for (i = 0; i < 8; i++) {
133 ndelay(700);
134 /* SDA:Read Data */
135 data |= ((__raw_readb(SCSPTR1) & SDA) >> 2) << (7 - i);
136 scsptr1_data &= ~SCL; /* SCL:L */
137 __raw_writeb(scsptr1_data, SCSPTR1);
138 ndelay(700);
139 scsptr1_data |= SCL; /* SCL:H */
140 __raw_writeb(scsptr1_data, SCSPTR1);
141 }
142 return data & 0x0F;
143}
144
145#endif /* CONFIG_SH_LANDISK */
146
147/*****************************************************/
148/* machine independence part of RS5C313 */
149/*****************************************************/
150
151/* RICOH RS5C313 address */
152#define RS5C313_ADDR_SEC 0x00
153#define RS5C313_ADDR_SEC10 0x01
154#define RS5C313_ADDR_MIN 0x02
155#define RS5C313_ADDR_MIN10 0x03
156#define RS5C313_ADDR_HOUR 0x04
157#define RS5C313_ADDR_HOUR10 0x05
158#define RS5C313_ADDR_WEEK 0x06
159#define RS5C313_ADDR_INTINTVREG 0x07
160#define RS5C313_ADDR_DAY 0x08
161#define RS5C313_ADDR_DAY10 0x09
162#define RS5C313_ADDR_MON 0x0A
163#define RS5C313_ADDR_MON10 0x0B
164#define RS5C313_ADDR_YEAR 0x0C
165#define RS5C313_ADDR_YEAR10 0x0D
166#define RS5C313_ADDR_CNTREG 0x0E
167#define RS5C313_ADDR_TESTREG 0x0F
168
169/* RICOH RS5C313 control register */
170#define RS5C313_CNTREG_ADJ_BSY 0x01
171#define RS5C313_CNTREG_WTEN_XSTP 0x02
172#define RS5C313_CNTREG_12_24 0x04
173#define RS5C313_CNTREG_CTFG 0x08
174
175/* RICOH RS5C313 test register */
176#define RS5C313_TESTREG_TEST 0x01
177
178/* RICOH RS5C313 control bit */
179#define RS5C313_CNTBIT_READ 0x40
180#define RS5C313_CNTBIT_AD 0x20
181#define RS5C313_CNTBIT_DT 0x10
182
183static unsigned char rs5c313_read_reg(unsigned char addr)
184{
185
186 rs5c313_write_data(addr | RS5C313_CNTBIT_READ | RS5C313_CNTBIT_AD);
187 return rs5c313_read_data();
188}
189
190static void rs5c313_write_reg(unsigned char addr, unsigned char data)
191{
192 data &= 0x0f;
193 rs5c313_write_data(addr | RS5C313_CNTBIT_AD);
194 rs5c313_write_data(data | RS5C313_CNTBIT_DT);
195 return;
196}
197
198static inline unsigned char rs5c313_read_cntreg(void)
199{
200 return rs5c313_read_reg(RS5C313_ADDR_CNTREG);
201}
202
203static inline void rs5c313_write_cntreg(unsigned char data)
204{
205 rs5c313_write_reg(RS5C313_ADDR_CNTREG, data);
206}
207
208static inline void rs5c313_write_intintvreg(unsigned char data)
209{
210 rs5c313_write_reg(RS5C313_ADDR_INTINTVREG, data);
211}
212
213static int rs5c313_rtc_read_time(struct device *dev, struct rtc_time *tm)
214{
215 int data;
216 int cnt;
217
218 cnt = 0;
219 while (1) {
220 RS5C313_CEENABLE; /* CE:H */
221
222 /* Initialize control reg. 24 hour */
223 rs5c313_write_cntreg(0x04);
224
225 if (!(rs5c313_read_cntreg() & RS5C313_CNTREG_ADJ_BSY))
226 break;
227
228 RS5C313_CEDISABLE;
229 ndelay(700); /* CE:L */
230
231 if (cnt++ > 100) {
232 dev_err(dev, "%s: timeout error\n", __func__);
233 return -EIO;
234 }
235 }
236
237 data = rs5c313_read_reg(RS5C313_ADDR_SEC);
238 data |= (rs5c313_read_reg(RS5C313_ADDR_SEC10) << 4);
239 tm->tm_sec = bcd2bin(data);
240
241 data = rs5c313_read_reg(RS5C313_ADDR_MIN);
242 data |= (rs5c313_read_reg(RS5C313_ADDR_MIN10) << 4);
243 tm->tm_min = bcd2bin(data);
244
245 data = rs5c313_read_reg(RS5C313_ADDR_HOUR);
246 data |= (rs5c313_read_reg(RS5C313_ADDR_HOUR10) << 4);
247 tm->tm_hour = bcd2bin(data);
248
249 data = rs5c313_read_reg(RS5C313_ADDR_DAY);
250 data |= (rs5c313_read_reg(RS5C313_ADDR_DAY10) << 4);
251 tm->tm_mday = bcd2bin(data);
252
253 data = rs5c313_read_reg(RS5C313_ADDR_MON);
254 data |= (rs5c313_read_reg(RS5C313_ADDR_MON10) << 4);
255 tm->tm_mon = bcd2bin(data) - 1;
256
257 data = rs5c313_read_reg(RS5C313_ADDR_YEAR);
258 data |= (rs5c313_read_reg(RS5C313_ADDR_YEAR10) << 4);
259 tm->tm_year = bcd2bin(data);
260
261 if (tm->tm_year < 70)
262 tm->tm_year += 100;
263
264 data = rs5c313_read_reg(RS5C313_ADDR_WEEK);
265 tm->tm_wday = bcd2bin(data);
266
267 RS5C313_CEDISABLE;
268 ndelay(700); /* CE:L */
269
270 return 0;
271}
272
273static int rs5c313_rtc_set_time(struct device *dev, struct rtc_time *tm)
274{
275 int data;
276 int cnt;
277
278 cnt = 0;
279 /* busy check. */
280 while (1) {
281 RS5C313_CEENABLE; /* CE:H */
282
283 /* Initialize control reg. 24 hour */
284 rs5c313_write_cntreg(0x04);
285
286 if (!(rs5c313_read_cntreg() & RS5C313_CNTREG_ADJ_BSY))
287 break;
288 RS5C313_MISCOP;
289 RS5C313_CEDISABLE;
290 ndelay(700); /* CE:L */
291
292 if (cnt++ > 100) {
293 dev_err(dev, "%s: timeout error\n", __func__);
294 return -EIO;
295 }
296 }
297
298 data = bin2bcd(tm->tm_sec);
299 rs5c313_write_reg(RS5C313_ADDR_SEC, data);
300 rs5c313_write_reg(RS5C313_ADDR_SEC10, (data >> 4));
301
302 data = bin2bcd(tm->tm_min);
303 rs5c313_write_reg(RS5C313_ADDR_MIN, data);
304 rs5c313_write_reg(RS5C313_ADDR_MIN10, (data >> 4));
305
306 data = bin2bcd(tm->tm_hour);
307 rs5c313_write_reg(RS5C313_ADDR_HOUR, data);
308 rs5c313_write_reg(RS5C313_ADDR_HOUR10, (data >> 4));
309
310 data = bin2bcd(tm->tm_mday);
311 rs5c313_write_reg(RS5C313_ADDR_DAY, data);
312 rs5c313_write_reg(RS5C313_ADDR_DAY10, (data >> 4));
313
314 data = bin2bcd(tm->tm_mon + 1);
315 rs5c313_write_reg(RS5C313_ADDR_MON, data);
316 rs5c313_write_reg(RS5C313_ADDR_MON10, (data >> 4));
317
318 data = bin2bcd(tm->tm_year % 100);
319 rs5c313_write_reg(RS5C313_ADDR_YEAR, data);
320 rs5c313_write_reg(RS5C313_ADDR_YEAR10, (data >> 4));
321
322 data = bin2bcd(tm->tm_wday);
323 rs5c313_write_reg(RS5C313_ADDR_WEEK, data);
324
325 RS5C313_CEDISABLE; /* CE:H */
326 ndelay(700);
327
328 return 0;
329}
330
331static void rs5c313_check_xstp_bit(void)
332{
333 struct rtc_time tm;
334 int cnt;
335
336 RS5C313_CEENABLE; /* CE:H */
337 if (rs5c313_read_cntreg() & RS5C313_CNTREG_WTEN_XSTP) {
338 /* INT interval reg. OFF */
339 rs5c313_write_intintvreg(0x00);
340 /* Initialize control reg. 24 hour & adjust */
341 rs5c313_write_cntreg(0x07);
342
343 /* busy check. */
344 for (cnt = 0; cnt < 100; cnt++) {
345 if (!(rs5c313_read_cntreg() & RS5C313_CNTREG_ADJ_BSY))
346 break;
347 RS5C313_MISCOP;
348 }
349
350 memset(&tm, 0, sizeof(struct rtc_time));
351 tm.tm_mday = 1;
352 tm.tm_mon = 1 - 1;
353 tm.tm_year = 2000 - 1900;
354
355 rs5c313_rtc_set_time(NULL, &tm);
356 pr_err("invalid value, resetting to 1 Jan 2000\n");
357 }
358 RS5C313_CEDISABLE;
359 ndelay(700); /* CE:L */
360}
361
362static const struct rtc_class_ops rs5c313_rtc_ops = {
363 .read_time = rs5c313_rtc_read_time,
364 .set_time = rs5c313_rtc_set_time,
365};
366
367static int rs5c313_rtc_probe(struct platform_device *pdev)
368{
369 struct rtc_device *rtc;
370
371 rs5c313_init_port();
372 rs5c313_check_xstp_bit();
373
374 rtc = devm_rtc_device_register(&pdev->dev, "rs5c313", &rs5c313_rtc_ops,
375 THIS_MODULE);
376
377 return PTR_ERR_OR_ZERO(rtc);
378}
379
380static struct platform_driver rs5c313_rtc_platform_driver = {
381 .driver = {
382 .name = DRV_NAME,
383 },
384 .probe = rs5c313_rtc_probe,
385};
386
387module_platform_driver(rs5c313_rtc_platform_driver);
388
389MODULE_AUTHOR("kogiidena , Nobuhiro Iwamatsu <[email protected]>");
390MODULE_DESCRIPTION("Ricoh RS5C313 RTC device driver");
391MODULE_LICENSE("GPL");
392MODULE_ALIAS("platform:" DRV_NAME);