sh: clkfwk: Handle NULL clkops for root clocks.
[linux-2.6/mini2440.git] / drivers / rtc / rtc-rs5c313.c
blobe6ea3f5ee1eb84836999111aff709888e9012c55
1 /*
2 * Ricoh RS5C313 RTC device/driver
3 * Copyright (C) 2007 Nobuhiro Iwamatsu
5 * 2005-09-19 modifed by kogiidena
7 * Based on the old drivers/char/rs5c313_rtc.c by:
8 * Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org>
9 * Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka
11 * Based on code written by Paul Gortmaker.
12 * Copyright (C) 1996 Paul Gortmaker
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.
18 * Based on other minimal char device drivers, like Alan's
19 * watchdog, Ted's random, etc. etc.
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: Updata driver.
42 #include <linux/module.h>
43 #include <linux/err.h>
44 #include <linux/rtc.h>
45 #include <linux/platform_device.h>
46 #include <linux/bcd.h>
47 #include <linux/delay.h>
48 #include <asm/io.h>
50 #define DRV_NAME "rs5c313"
51 #define DRV_VERSION "1.13"
53 #ifdef CONFIG_SH_LANDISK
54 /*****************************************************/
55 /* LANDISK dependence part of RS5C313 */
56 /*****************************************************/
58 #define SCSMR1 0xFFE00000
59 #define SCSCR1 0xFFE00008
60 #define SCSMR1_CA 0x80
61 #define SCSCR1_CKE 0x03
62 #define SCSPTR1 0xFFE0001C
63 #define SCSPTR1_EIO 0x80
64 #define SCSPTR1_SPB1IO 0x08
65 #define SCSPTR1_SPB1DT 0x04
66 #define SCSPTR1_SPB0IO 0x02
67 #define SCSPTR1_SPB0DT 0x01
69 #define SDA_OEN SCSPTR1_SPB1IO
70 #define SDA SCSPTR1_SPB1DT
71 #define SCL_OEN SCSPTR1_SPB0IO
72 #define SCL SCSPTR1_SPB0DT
74 /* RICOH RS5C313 CE port */
75 #define RS5C313_CE 0xB0000003
77 /* RICOH RS5C313 CE port bit */
78 #define RS5C313_CE_RTCCE 0x02
80 /* SCSPTR1 data */
81 unsigned char scsptr1_data;
83 #define RS5C313_CEENABLE ctrl_outb(RS5C313_CE_RTCCE, RS5C313_CE);
84 #define RS5C313_CEDISABLE ctrl_outb(0x00, RS5C313_CE)
85 #define RS5C313_MISCOP ctrl_outb(0x02, 0xB0000008)
87 static void rs5c313_init_port(void)
89 /* Set SCK as I/O port and Initialize SCSPTR1 data & I/O port. */
90 ctrl_outb(ctrl_inb(SCSMR1) & ~SCSMR1_CA, SCSMR1);
91 ctrl_outb(ctrl_inb(SCSCR1) & ~SCSCR1_CKE, SCSCR1);
93 /* And Initialize SCL for RS5C313 clock */
94 scsptr1_data = ctrl_inb(SCSPTR1) | SCL; /* SCL:H */
95 ctrl_outb(scsptr1_data, SCSPTR1);
96 scsptr1_data = ctrl_inb(SCSPTR1) | SCL_OEN; /* SCL output enable */
97 ctrl_outb(scsptr1_data, SCSPTR1);
98 RS5C313_CEDISABLE; /* CE:L */
101 static void rs5c313_write_data(unsigned char data)
103 int i;
105 for (i = 0; i < 8; i++) {
106 /* SDA:Write Data */
107 scsptr1_data = (scsptr1_data & ~SDA) |
108 ((((0x80 >> i) & data) >> (7 - i)) << 2);
109 ctrl_outb(scsptr1_data, SCSPTR1);
110 if (i == 0) {
111 scsptr1_data |= SDA_OEN; /* SDA:output enable */
112 ctrl_outb(scsptr1_data, SCSPTR1);
114 ndelay(700);
115 scsptr1_data &= ~SCL; /* SCL:L */
116 ctrl_outb(scsptr1_data, SCSPTR1);
117 ndelay(700);
118 scsptr1_data |= SCL; /* SCL:H */
119 ctrl_outb(scsptr1_data, SCSPTR1);
122 scsptr1_data &= ~SDA_OEN; /* SDA:output disable */
123 ctrl_outb(scsptr1_data, SCSPTR1);
126 static unsigned char rs5c313_read_data(void)
128 int i;
129 unsigned char data = 0;
131 for (i = 0; i < 8; i++) {
132 ndelay(700);
133 /* SDA:Read Data */
134 data |= ((ctrl_inb(SCSPTR1) & SDA) >> 2) << (7 - i);
135 scsptr1_data &= ~SCL; /* SCL:L */
136 ctrl_outb(scsptr1_data, SCSPTR1);
137 ndelay(700);
138 scsptr1_data |= SCL; /* SCL:H */
139 ctrl_outb(scsptr1_data, SCSPTR1);
141 return data & 0x0F;
144 #endif /* CONFIG_SH_LANDISK */
146 /*****************************************************/
147 /* machine independence part of RS5C313 */
148 /*****************************************************/
150 /* RICOH RS5C313 address */
151 #define RS5C313_ADDR_SEC 0x00
152 #define RS5C313_ADDR_SEC10 0x01
153 #define RS5C313_ADDR_MIN 0x02
154 #define RS5C313_ADDR_MIN10 0x03
155 #define RS5C313_ADDR_HOUR 0x04
156 #define RS5C313_ADDR_HOUR10 0x05
157 #define RS5C313_ADDR_WEEK 0x06
158 #define RS5C313_ADDR_INTINTVREG 0x07
159 #define RS5C313_ADDR_DAY 0x08
160 #define RS5C313_ADDR_DAY10 0x09
161 #define RS5C313_ADDR_MON 0x0A
162 #define RS5C313_ADDR_MON10 0x0B
163 #define RS5C313_ADDR_YEAR 0x0C
164 #define RS5C313_ADDR_YEAR10 0x0D
165 #define RS5C313_ADDR_CNTREG 0x0E
166 #define RS5C313_ADDR_TESTREG 0x0F
168 /* RICOH RS5C313 control register */
169 #define RS5C313_CNTREG_ADJ_BSY 0x01
170 #define RS5C313_CNTREG_WTEN_XSTP 0x02
171 #define RS5C313_CNTREG_12_24 0x04
172 #define RS5C313_CNTREG_CTFG 0x08
174 /* RICOH RS5C313 test register */
175 #define RS5C313_TESTREG_TEST 0x01
177 /* RICOH RS5C313 control bit */
178 #define RS5C313_CNTBIT_READ 0x40
179 #define RS5C313_CNTBIT_AD 0x20
180 #define RS5C313_CNTBIT_DT 0x10
182 static unsigned char rs5c313_read_reg(unsigned char addr)
185 rs5c313_write_data(addr | RS5C313_CNTBIT_READ | RS5C313_CNTBIT_AD);
186 return rs5c313_read_data();
189 static void rs5c313_write_reg(unsigned char addr, unsigned char data)
191 data &= 0x0f;
192 rs5c313_write_data(addr | RS5C313_CNTBIT_AD);
193 rs5c313_write_data(data | RS5C313_CNTBIT_DT);
194 return;
197 static inline unsigned char rs5c313_read_cntreg(void)
199 return rs5c313_read_reg(RS5C313_ADDR_CNTREG);
202 static inline void rs5c313_write_cntreg(unsigned char data)
204 rs5c313_write_reg(RS5C313_ADDR_CNTREG, data);
207 static inline void rs5c313_write_intintvreg(unsigned char data)
209 rs5c313_write_reg(RS5C313_ADDR_INTINTVREG, data);
212 static int rs5c313_rtc_read_time(struct device *dev, struct rtc_time *tm)
214 int data;
215 int cnt;
217 cnt = 0;
218 while (1) {
219 RS5C313_CEENABLE; /* CE:H */
221 /* Initialize control reg. 24 hour */
222 rs5c313_write_cntreg(0x04);
224 if (!(rs5c313_read_cntreg() & RS5C313_CNTREG_ADJ_BSY))
225 break;
227 RS5C313_CEDISABLE;
228 ndelay(700); /* CE:L */
230 if (cnt++ > 100) {
231 dev_err(dev, "%s: timeout error\n", __func__);
232 return -EIO;
236 data = rs5c313_read_reg(RS5C313_ADDR_SEC);
237 data |= (rs5c313_read_reg(RS5C313_ADDR_SEC10) << 4);
238 tm->tm_sec = bcd2bin(data);
240 data = rs5c313_read_reg(RS5C313_ADDR_MIN);
241 data |= (rs5c313_read_reg(RS5C313_ADDR_MIN10) << 4);
242 tm->tm_min = bcd2bin(data);
244 data = rs5c313_read_reg(RS5C313_ADDR_HOUR);
245 data |= (rs5c313_read_reg(RS5C313_ADDR_HOUR10) << 4);
246 tm->tm_hour = bcd2bin(data);
248 data = rs5c313_read_reg(RS5C313_ADDR_DAY);
249 data |= (rs5c313_read_reg(RS5C313_ADDR_DAY10) << 4);
250 tm->tm_mday = bcd2bin(data);
252 data = rs5c313_read_reg(RS5C313_ADDR_MON);
253 data |= (rs5c313_read_reg(RS5C313_ADDR_MON10) << 4);
254 tm->tm_mon = bcd2bin(data) - 1;
256 data = rs5c313_read_reg(RS5C313_ADDR_YEAR);
257 data |= (rs5c313_read_reg(RS5C313_ADDR_YEAR10) << 4);
258 tm->tm_year = bcd2bin(data);
260 if (tm->tm_year < 70)
261 tm->tm_year += 100;
263 data = rs5c313_read_reg(RS5C313_ADDR_WEEK);
264 tm->tm_wday = bcd2bin(data);
266 RS5C313_CEDISABLE;
267 ndelay(700); /* CE:L */
269 return 0;
272 static int rs5c313_rtc_set_time(struct device *dev, struct rtc_time *tm)
274 int data;
275 int cnt;
277 cnt = 0;
278 /* busy check. */
279 while (1) {
280 RS5C313_CEENABLE; /* CE:H */
282 /* Initiatlize control reg. 24 hour */
283 rs5c313_write_cntreg(0x04);
285 if (!(rs5c313_read_cntreg() & RS5C313_CNTREG_ADJ_BSY))
286 break;
287 RS5C313_MISCOP;
288 RS5C313_CEDISABLE;
289 ndelay(700); /* CE:L */
291 if (cnt++ > 100) {
292 dev_err(dev, "%s: timeout error\n", __func__);
293 return -EIO;
297 data = bin2bcd(tm->tm_sec);
298 rs5c313_write_reg(RS5C313_ADDR_SEC, data);
299 rs5c313_write_reg(RS5C313_ADDR_SEC10, (data >> 4));
301 data = bin2bcd(tm->tm_min);
302 rs5c313_write_reg(RS5C313_ADDR_MIN, data );
303 rs5c313_write_reg(RS5C313_ADDR_MIN10, (data >> 4));
305 data = bin2bcd(tm->tm_hour);
306 rs5c313_write_reg(RS5C313_ADDR_HOUR, data);
307 rs5c313_write_reg(RS5C313_ADDR_HOUR10, (data >> 4));
309 data = bin2bcd(tm->tm_mday);
310 rs5c313_write_reg(RS5C313_ADDR_DAY, data);
311 rs5c313_write_reg(RS5C313_ADDR_DAY10, (data>> 4));
313 data = bin2bcd(tm->tm_mon + 1);
314 rs5c313_write_reg(RS5C313_ADDR_MON, data);
315 rs5c313_write_reg(RS5C313_ADDR_MON10, (data >> 4));
317 data = bin2bcd(tm->tm_year % 100);
318 rs5c313_write_reg(RS5C313_ADDR_YEAR, data);
319 rs5c313_write_reg(RS5C313_ADDR_YEAR10, (data >> 4));
321 data = bin2bcd(tm->tm_wday);
322 rs5c313_write_reg(RS5C313_ADDR_WEEK, data);
324 RS5C313_CEDISABLE; /* CE:H */
325 ndelay(700);
327 return 0;
330 static void rs5c313_check_xstp_bit(void)
332 struct rtc_time tm;
333 int cnt;
335 RS5C313_CEENABLE; /* CE:H */
336 if (rs5c313_read_cntreg() & RS5C313_CNTREG_WTEN_XSTP) {
337 /* INT interval reg. OFF */
338 rs5c313_write_intintvreg(0x00);
339 /* Initialize control reg. 24 hour & adjust */
340 rs5c313_write_cntreg(0x07);
342 /* busy check. */
343 for (cnt = 0; cnt < 100; cnt++) {
344 if (!(rs5c313_read_cntreg() & RS5C313_CNTREG_ADJ_BSY))
345 break;
346 RS5C313_MISCOP;
349 memset(&tm, 0, sizeof(struct rtc_time));
350 tm.tm_mday = 1;
351 tm.tm_mon = 1 - 1;
352 tm.tm_year = 2000 - 1900;
354 rs5c313_rtc_set_time(NULL, &tm);
355 printk(KERN_ERR "RICHO RS5C313: invalid value, resetting to "
356 "1 Jan 2000\n");
358 RS5C313_CEDISABLE;
359 ndelay(700); /* CE:L */
362 static const struct rtc_class_ops rs5c313_rtc_ops = {
363 .read_time = rs5c313_rtc_read_time,
364 .set_time = rs5c313_rtc_set_time,
367 static int rs5c313_rtc_probe(struct platform_device *pdev)
369 struct rtc_device *rtc = rtc_device_register("rs5c313", &pdev->dev,
370 &rs5c313_rtc_ops, THIS_MODULE);
372 if (IS_ERR(rtc))
373 return PTR_ERR(rtc);
375 platform_set_drvdata(pdev, rtc);
377 return 0;
380 static int __devexit rs5c313_rtc_remove(struct platform_device *pdev)
382 struct rtc_device *rtc = platform_get_drvdata( pdev );
384 rtc_device_unregister(rtc);
386 return 0;
389 static struct platform_driver rs5c313_rtc_platform_driver = {
390 .driver = {
391 .name = DRV_NAME,
392 .owner = THIS_MODULE,
394 .probe = rs5c313_rtc_probe,
395 .remove = __devexit_p( rs5c313_rtc_remove ),
398 static int __init rs5c313_rtc_init(void)
400 int err;
402 err = platform_driver_register(&rs5c313_rtc_platform_driver);
403 if (err)
404 return err;
406 rs5c313_init_port();
407 rs5c313_check_xstp_bit();
409 return 0;
412 static void __exit rs5c313_rtc_exit(void)
414 platform_driver_unregister( &rs5c313_rtc_platform_driver );
417 module_init(rs5c313_rtc_init);
418 module_exit(rs5c313_rtc_exit);
420 MODULE_VERSION(DRV_VERSION);
421 MODULE_AUTHOR("kogiidena , Nobuhiro Iwamatsu <iwamatsu@nigauri.org>");
422 MODULE_DESCRIPTION("Ricoh RS5C313 RTC device driver");
423 MODULE_LICENSE("GPL");
424 MODULE_ALIAS("platform:" DRV_NAME);