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v5.9
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * ST M48T59 RTC driver
  4 *
  5 * Copyright (c) 2007 Wind River Systems, Inc.
  6 *
  7 * Author: Mark Zhan <rongkai.zhan@windriver.com>
 
 
 
 
  8 */
  9
 10#include <linux/kernel.h>
 11#include <linux/module.h>
 12#include <linux/init.h>
 13#include <linux/io.h>
 14#include <linux/device.h>
 15#include <linux/platform_device.h>
 16#include <linux/rtc.h>
 17#include <linux/rtc/m48t59.h>
 18#include <linux/bcd.h>
 19#include <linux/slab.h>
 20
 21#ifndef NO_IRQ
 22#define NO_IRQ	(-1)
 23#endif
 24
 25#define M48T59_READ(reg) (pdata->read_byte(dev, pdata->offset + reg))
 26#define M48T59_WRITE(val, reg) \
 27	(pdata->write_byte(dev, pdata->offset + reg, val))
 28
 29#define M48T59_SET_BITS(mask, reg)	\
 30	M48T59_WRITE((M48T59_READ(reg) | (mask)), (reg))
 31#define M48T59_CLEAR_BITS(mask, reg)	\
 32	M48T59_WRITE((M48T59_READ(reg) & ~(mask)), (reg))
 33
 34struct m48t59_private {
 35	void __iomem *ioaddr;
 36	int irq;
 37	struct rtc_device *rtc;
 38	spinlock_t lock; /* serialize the NVRAM and RTC access */
 39};
 40
 41/*
 42 * This is the generic access method when the chip is memory-mapped
 43 */
 44static void
 45m48t59_mem_writeb(struct device *dev, u32 ofs, u8 val)
 46{
 47	struct m48t59_private *m48t59 = dev_get_drvdata(dev);
 
 48
 49	writeb(val, m48t59->ioaddr+ofs);
 50}
 51
 52static u8
 53m48t59_mem_readb(struct device *dev, u32 ofs)
 54{
 55	struct m48t59_private *m48t59 = dev_get_drvdata(dev);
 
 56
 57	return readb(m48t59->ioaddr+ofs);
 58}
 59
 60/*
 61 * NOTE: M48T59 only uses BCD mode
 62 */
 63static int m48t59_rtc_read_time(struct device *dev, struct rtc_time *tm)
 64{
 65	struct m48t59_plat_data *pdata = dev_get_platdata(dev);
 66	struct m48t59_private *m48t59 = dev_get_drvdata(dev);
 
 67	unsigned long flags;
 68	u8 val;
 69
 70	spin_lock_irqsave(&m48t59->lock, flags);
 71	/* Issue the READ command */
 72	M48T59_SET_BITS(M48T59_CNTL_READ, M48T59_CNTL);
 73
 74	tm->tm_year	= bcd2bin(M48T59_READ(M48T59_YEAR));
 75	/* tm_mon is 0-11 */
 76	tm->tm_mon	= bcd2bin(M48T59_READ(M48T59_MONTH)) - 1;
 77	tm->tm_mday	= bcd2bin(M48T59_READ(M48T59_MDAY));
 78
 79	val = M48T59_READ(M48T59_WDAY);
 80	if ((pdata->type == M48T59RTC_TYPE_M48T59) &&
 81	    (val & M48T59_WDAY_CEB) && (val & M48T59_WDAY_CB)) {
 82		dev_dbg(dev, "Century bit is enabled\n");
 83		tm->tm_year += 100;	/* one century */
 84	}
 85#ifdef CONFIG_SPARC
 86	/* Sun SPARC machines count years since 1968 */
 87	tm->tm_year += 68;
 88#endif
 89
 90	tm->tm_wday	= bcd2bin(val & 0x07);
 91	tm->tm_hour	= bcd2bin(M48T59_READ(M48T59_HOUR) & 0x3F);
 92	tm->tm_min	= bcd2bin(M48T59_READ(M48T59_MIN) & 0x7F);
 93	tm->tm_sec	= bcd2bin(M48T59_READ(M48T59_SEC) & 0x7F);
 94
 95	/* Clear the READ bit */
 96	M48T59_CLEAR_BITS(M48T59_CNTL_READ, M48T59_CNTL);
 97	spin_unlock_irqrestore(&m48t59->lock, flags);
 98
 99	dev_dbg(dev, "RTC read time %ptR\n", tm);
100	return 0;
 
 
101}
102
103static int m48t59_rtc_set_time(struct device *dev, struct rtc_time *tm)
104{
105	struct m48t59_plat_data *pdata = dev_get_platdata(dev);
106	struct m48t59_private *m48t59 = dev_get_drvdata(dev);
 
107	unsigned long flags;
108	u8 val = 0;
109	int year = tm->tm_year;
110
111#ifdef CONFIG_SPARC
112	/* Sun SPARC machines count years since 1968 */
113	year -= 68;
114#endif
115
116	dev_dbg(dev, "RTC set time %04d-%02d-%02d %02d/%02d/%02d\n",
117		year + 1900, tm->tm_mon, tm->tm_mday,
118		tm->tm_hour, tm->tm_min, tm->tm_sec);
119
120	if (year < 0)
121		return -EINVAL;
122
123	spin_lock_irqsave(&m48t59->lock, flags);
124	/* Issue the WRITE command */
125	M48T59_SET_BITS(M48T59_CNTL_WRITE, M48T59_CNTL);
126
127	M48T59_WRITE((bin2bcd(tm->tm_sec) & 0x7F), M48T59_SEC);
128	M48T59_WRITE((bin2bcd(tm->tm_min) & 0x7F), M48T59_MIN);
129	M48T59_WRITE((bin2bcd(tm->tm_hour) & 0x3F), M48T59_HOUR);
130	M48T59_WRITE((bin2bcd(tm->tm_mday) & 0x3F), M48T59_MDAY);
131	/* tm_mon is 0-11 */
132	M48T59_WRITE((bin2bcd(tm->tm_mon + 1) & 0x1F), M48T59_MONTH);
133	M48T59_WRITE(bin2bcd(year % 100), M48T59_YEAR);
134
135	if (pdata->type == M48T59RTC_TYPE_M48T59 && (year / 100))
136		val = (M48T59_WDAY_CEB | M48T59_WDAY_CB);
137	val |= (bin2bcd(tm->tm_wday) & 0x07);
138	M48T59_WRITE(val, M48T59_WDAY);
139
140	/* Clear the WRITE bit */
141	M48T59_CLEAR_BITS(M48T59_CNTL_WRITE, M48T59_CNTL);
142	spin_unlock_irqrestore(&m48t59->lock, flags);
143	return 0;
144}
145
146/*
147 * Read alarm time and date in RTC
148 */
149static int m48t59_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
150{
151	struct m48t59_plat_data *pdata = dev_get_platdata(dev);
152	struct m48t59_private *m48t59 = dev_get_drvdata(dev);
 
153	struct rtc_time *tm = &alrm->time;
154	unsigned long flags;
155	u8 val;
156
157	/* If no irq, we don't support ALARM */
158	if (m48t59->irq == NO_IRQ)
159		return -EIO;
160
161	spin_lock_irqsave(&m48t59->lock, flags);
162	/* Issue the READ command */
163	M48T59_SET_BITS(M48T59_CNTL_READ, M48T59_CNTL);
164
165	tm->tm_year = bcd2bin(M48T59_READ(M48T59_YEAR));
166#ifdef CONFIG_SPARC
167	/* Sun SPARC machines count years since 1968 */
168	tm->tm_year += 68;
169#endif
170	/* tm_mon is 0-11 */
171	tm->tm_mon = bcd2bin(M48T59_READ(M48T59_MONTH)) - 1;
172
173	val = M48T59_READ(M48T59_WDAY);
174	if ((val & M48T59_WDAY_CEB) && (val & M48T59_WDAY_CB))
175		tm->tm_year += 100;	/* one century */
176
177	tm->tm_mday = bcd2bin(M48T59_READ(M48T59_ALARM_DATE));
178	tm->tm_hour = bcd2bin(M48T59_READ(M48T59_ALARM_HOUR));
179	tm->tm_min = bcd2bin(M48T59_READ(M48T59_ALARM_MIN));
180	tm->tm_sec = bcd2bin(M48T59_READ(M48T59_ALARM_SEC));
181
182	/* Clear the READ bit */
183	M48T59_CLEAR_BITS(M48T59_CNTL_READ, M48T59_CNTL);
184	spin_unlock_irqrestore(&m48t59->lock, flags);
185
186	dev_dbg(dev, "RTC read alarm time %ptR\n", tm);
 
 
187	return rtc_valid_tm(tm);
188}
189
190/*
191 * Set alarm time and date in RTC
192 */
193static int m48t59_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
194{
195	struct m48t59_plat_data *pdata = dev_get_platdata(dev);
196	struct m48t59_private *m48t59 = dev_get_drvdata(dev);
 
197	struct rtc_time *tm = &alrm->time;
198	u8 mday, hour, min, sec;
199	unsigned long flags;
200	int year = tm->tm_year;
201
202#ifdef CONFIG_SPARC
203	/* Sun SPARC machines count years since 1968 */
204	year -= 68;
205#endif
206
207	/* If no irq, we don't support ALARM */
208	if (m48t59->irq == NO_IRQ)
209		return -EIO;
210
211	if (year < 0)
212		return -EINVAL;
213
214	/*
215	 * 0xff means "always match"
216	 */
217	mday = tm->tm_mday;
218	mday = (mday >= 1 && mday <= 31) ? bin2bcd(mday) : 0xff;
219	if (mday == 0xff)
220		mday = M48T59_READ(M48T59_MDAY);
221
222	hour = tm->tm_hour;
223	hour = (hour < 24) ? bin2bcd(hour) : 0x00;
224
225	min = tm->tm_min;
226	min = (min < 60) ? bin2bcd(min) : 0x00;
227
228	sec = tm->tm_sec;
229	sec = (sec < 60) ? bin2bcd(sec) : 0x00;
230
231	spin_lock_irqsave(&m48t59->lock, flags);
232	/* Issue the WRITE command */
233	M48T59_SET_BITS(M48T59_CNTL_WRITE, M48T59_CNTL);
234
235	M48T59_WRITE(mday, M48T59_ALARM_DATE);
236	M48T59_WRITE(hour, M48T59_ALARM_HOUR);
237	M48T59_WRITE(min, M48T59_ALARM_MIN);
238	M48T59_WRITE(sec, M48T59_ALARM_SEC);
239
240	/* Clear the WRITE bit */
241	M48T59_CLEAR_BITS(M48T59_CNTL_WRITE, M48T59_CNTL);
242	spin_unlock_irqrestore(&m48t59->lock, flags);
243
244	dev_dbg(dev, "RTC set alarm time %04d-%02d-%02d %02d/%02d/%02d\n",
245		year + 1900, tm->tm_mon, tm->tm_mday,
246		tm->tm_hour, tm->tm_min, tm->tm_sec);
247	return 0;
248}
249
250/*
251 * Handle commands from user-space
252 */
253static int m48t59_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
254{
255	struct m48t59_plat_data *pdata = dev_get_platdata(dev);
256	struct m48t59_private *m48t59 = dev_get_drvdata(dev);
 
257	unsigned long flags;
258
259	spin_lock_irqsave(&m48t59->lock, flags);
260	if (enabled)
261		M48T59_WRITE(M48T59_INTR_AFE, M48T59_INTR);
262	else
263		M48T59_WRITE(0x00, M48T59_INTR);
264	spin_unlock_irqrestore(&m48t59->lock, flags);
265
266	return 0;
267}
268
269static int m48t59_rtc_proc(struct device *dev, struct seq_file *seq)
270{
271	struct m48t59_plat_data *pdata = dev_get_platdata(dev);
272	struct m48t59_private *m48t59 = dev_get_drvdata(dev);
 
273	unsigned long flags;
274	u8 val;
275
276	spin_lock_irqsave(&m48t59->lock, flags);
277	val = M48T59_READ(M48T59_FLAGS);
278	spin_unlock_irqrestore(&m48t59->lock, flags);
279
280	seq_printf(seq, "battery\t\t: %s\n",
281		 (val & M48T59_FLAGS_BF) ? "low" : "normal");
282	return 0;
283}
284
285/*
286 * IRQ handler for the RTC
287 */
288static irqreturn_t m48t59_rtc_interrupt(int irq, void *dev_id)
289{
290	struct device *dev = (struct device *)dev_id;
291	struct m48t59_plat_data *pdata = dev_get_platdata(dev);
292	struct m48t59_private *m48t59 = dev_get_drvdata(dev);
 
293	u8 event;
294
295	spin_lock(&m48t59->lock);
296	event = M48T59_READ(M48T59_FLAGS);
297	spin_unlock(&m48t59->lock);
298
299	if (event & M48T59_FLAGS_AF) {
300		rtc_update_irq(m48t59->rtc, 1, (RTC_AF | RTC_IRQF));
301		return IRQ_HANDLED;
302	}
303
304	return IRQ_NONE;
305}
306
307static const struct rtc_class_ops m48t59_rtc_ops = {
308	.read_time	= m48t59_rtc_read_time,
309	.set_time	= m48t59_rtc_set_time,
310	.read_alarm	= m48t59_rtc_readalarm,
311	.set_alarm	= m48t59_rtc_setalarm,
312	.proc		= m48t59_rtc_proc,
313	.alarm_irq_enable = m48t59_rtc_alarm_irq_enable,
314};
315
316static const struct rtc_class_ops m48t02_rtc_ops = {
317	.read_time	= m48t59_rtc_read_time,
318	.set_time	= m48t59_rtc_set_time,
319};
320
321static int m48t59_nvram_read(void *priv, unsigned int offset, void *val,
322			     size_t size)
323{
324	struct platform_device *pdev = priv;
325	struct device *dev = &pdev->dev;
326	struct m48t59_plat_data *pdata = dev_get_platdata(&pdev->dev);
 
327	struct m48t59_private *m48t59 = platform_get_drvdata(pdev);
328	ssize_t cnt = 0;
329	unsigned long flags;
330	u8 *buf = val;
331
332	spin_lock_irqsave(&m48t59->lock, flags);
333
334	for (; cnt < size; cnt++)
335		*buf++ = M48T59_READ(cnt);
 
 
336
337	spin_unlock_irqrestore(&m48t59->lock, flags);
338
339	return 0;
340}
341
342static int m48t59_nvram_write(void *priv, unsigned int offset, void *val,
343			      size_t size)
 
344{
345	struct platform_device *pdev = priv;
346	struct device *dev = &pdev->dev;
347	struct m48t59_plat_data *pdata = dev_get_platdata(&pdev->dev);
348	struct m48t59_private *m48t59 = platform_get_drvdata(pdev);
349	ssize_t cnt = 0;
350	unsigned long flags;
351	u8 *buf = val;
352
353	spin_lock_irqsave(&m48t59->lock, flags);
354
355	for (; cnt < size; cnt++)
356		M48T59_WRITE(*buf++, cnt);
 
 
357
358	spin_unlock_irqrestore(&m48t59->lock, flags);
359
360	return 0;
361}
362
363static int m48t59_rtc_probe(struct platform_device *pdev)
 
 
 
 
 
 
 
 
 
364{
365	struct m48t59_plat_data *pdata = dev_get_platdata(&pdev->dev);
366	struct m48t59_private *m48t59 = NULL;
367	struct resource *res;
368	int ret = -ENOMEM;
 
369	const struct rtc_class_ops *ops;
370	struct nvmem_config nvmem_cfg = {
371		.name = "m48t59-",
372		.word_size = 1,
373		.stride = 1,
374		.reg_read = m48t59_nvram_read,
375		.reg_write = m48t59_nvram_write,
376		.priv = pdev,
377	};
378
379	/* This chip could be memory-mapped or I/O-mapped */
380	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
381	if (!res) {
382		res = platform_get_resource(pdev, IORESOURCE_IO, 0);
383		if (!res)
384			return -EINVAL;
385	}
386
387	if (res->flags & IORESOURCE_IO) {
388		/* If we are I/O-mapped, the platform should provide
389		 * the operations accessing chip registers.
390		 */
391		if (!pdata || !pdata->write_byte || !pdata->read_byte)
392			return -EINVAL;
393	} else if (res->flags & IORESOURCE_MEM) {
394		/* we are memory-mapped */
395		if (!pdata) {
396			pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata),
397						GFP_KERNEL);
398			if (!pdata)
399				return -ENOMEM;
400			/* Ensure we only kmalloc platform data once */
401			pdev->dev.platform_data = pdata;
402		}
403		if (!pdata->type)
404			pdata->type = M48T59RTC_TYPE_M48T59;
405
406		/* Try to use the generic memory read/write ops */
407		if (!pdata->write_byte)
408			pdata->write_byte = m48t59_mem_writeb;
409		if (!pdata->read_byte)
410			pdata->read_byte = m48t59_mem_readb;
411	}
412
413	m48t59 = devm_kzalloc(&pdev->dev, sizeof(*m48t59), GFP_KERNEL);
414	if (!m48t59)
415		return -ENOMEM;
416
417	m48t59->ioaddr = pdata->ioaddr;
418
419	if (!m48t59->ioaddr) {
420		/* ioaddr not mapped externally */
421		m48t59->ioaddr = devm_ioremap(&pdev->dev, res->start,
422						resource_size(res));
423		if (!m48t59->ioaddr)
424			return ret;
425	}
426
427	/* Try to get irq number. We also can work in
428	 * the mode without IRQ.
429	 */
430	m48t59->irq = platform_get_irq(pdev, 0);
431	if (m48t59->irq <= 0)
432		m48t59->irq = NO_IRQ;
433
434	if (m48t59->irq != NO_IRQ) {
435		ret = devm_request_irq(&pdev->dev, m48t59->irq,
436				m48t59_rtc_interrupt, IRQF_SHARED,
437				"rtc-m48t59", &pdev->dev);
438		if (ret)
439			return ret;
440	}
441	switch (pdata->type) {
442	case M48T59RTC_TYPE_M48T59:
 
443		ops = &m48t59_rtc_ops;
444		pdata->offset = 0x1ff0;
445		break;
446	case M48T59RTC_TYPE_M48T02:
 
447		ops = &m48t02_rtc_ops;
448		pdata->offset = 0x7f0;
449		break;
450	case M48T59RTC_TYPE_M48T08:
 
451		ops = &m48t02_rtc_ops;
452		pdata->offset = 0x1ff0;
453		break;
454	default:
455		dev_err(&pdev->dev, "Unknown RTC type\n");
456		return -ENODEV;
 
457	}
458
459	spin_lock_init(&m48t59->lock);
460	platform_set_drvdata(pdev, m48t59);
461
462	m48t59->rtc = devm_rtc_allocate_device(&pdev->dev);
463	if (IS_ERR(m48t59->rtc))
464		return PTR_ERR(m48t59->rtc);
465
466	m48t59->rtc->nvram_old_abi = true;
467	m48t59->rtc->ops = ops;
468
469	nvmem_cfg.size = pdata->offset;
470	ret = rtc_nvmem_register(m48t59->rtc, &nvmem_cfg);
471	if (ret)
472		return ret;
473
474	ret = rtc_register_device(m48t59->rtc);
475	if (ret)
476		return ret;
477
478	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
479}
480
481/* work with hotplug and coldplug */
482MODULE_ALIAS("platform:rtc-m48t59");
483
484static struct platform_driver m48t59_rtc_driver = {
485	.driver		= {
486		.name	= "rtc-m48t59",
 
487	},
488	.probe		= m48t59_rtc_probe,
 
489};
490
491module_platform_driver(m48t59_rtc_driver);
 
 
 
 
 
 
 
 
 
 
 
492
493MODULE_AUTHOR("Mark Zhan <rongkai.zhan@windriver.com>");
494MODULE_DESCRIPTION("M48T59/M48T02/M48T08 RTC driver");
495MODULE_LICENSE("GPL");
v3.1
 
  1/*
  2 * ST M48T59 RTC driver
  3 *
  4 * Copyright (c) 2007 Wind River Systems, Inc.
  5 *
  6 * Author: Mark Zhan <rongkai.zhan@windriver.com>
  7 *
  8 * This program is free software; you can redistribute it and/or modify
  9 * it under the terms of the GNU General Public License version 2 as
 10 * published by the Free Software Foundation.
 11 */
 12
 13#include <linux/kernel.h>
 14#include <linux/module.h>
 15#include <linux/init.h>
 16#include <linux/io.h>
 17#include <linux/device.h>
 18#include <linux/platform_device.h>
 19#include <linux/rtc.h>
 20#include <linux/rtc/m48t59.h>
 21#include <linux/bcd.h>
 22#include <linux/slab.h>
 23
 24#ifndef NO_IRQ
 25#define NO_IRQ	(-1)
 26#endif
 27
 28#define M48T59_READ(reg) (pdata->read_byte(dev, pdata->offset + reg))
 29#define M48T59_WRITE(val, reg) \
 30	(pdata->write_byte(dev, pdata->offset + reg, val))
 31
 32#define M48T59_SET_BITS(mask, reg)	\
 33	M48T59_WRITE((M48T59_READ(reg) | (mask)), (reg))
 34#define M48T59_CLEAR_BITS(mask, reg)	\
 35	M48T59_WRITE((M48T59_READ(reg) & ~(mask)), (reg))
 36
 37struct m48t59_private {
 38	void __iomem *ioaddr;
 39	int irq;
 40	struct rtc_device *rtc;
 41	spinlock_t lock; /* serialize the NVRAM and RTC access */
 42};
 43
 44/*
 45 * This is the generic access method when the chip is memory-mapped
 46 */
 47static void
 48m48t59_mem_writeb(struct device *dev, u32 ofs, u8 val)
 49{
 50	struct platform_device *pdev = to_platform_device(dev);
 51	struct m48t59_private *m48t59 = platform_get_drvdata(pdev);
 52
 53	writeb(val, m48t59->ioaddr+ofs);
 54}
 55
 56static u8
 57m48t59_mem_readb(struct device *dev, u32 ofs)
 58{
 59	struct platform_device *pdev = to_platform_device(dev);
 60	struct m48t59_private *m48t59 = platform_get_drvdata(pdev);
 61
 62	return readb(m48t59->ioaddr+ofs);
 63}
 64
 65/*
 66 * NOTE: M48T59 only uses BCD mode
 67 */
 68static int m48t59_rtc_read_time(struct device *dev, struct rtc_time *tm)
 69{
 70	struct platform_device *pdev = to_platform_device(dev);
 71	struct m48t59_plat_data *pdata = pdev->dev.platform_data;
 72	struct m48t59_private *m48t59 = platform_get_drvdata(pdev);
 73	unsigned long flags;
 74	u8 val;
 75
 76	spin_lock_irqsave(&m48t59->lock, flags);
 77	/* Issue the READ command */
 78	M48T59_SET_BITS(M48T59_CNTL_READ, M48T59_CNTL);
 79
 80	tm->tm_year	= bcd2bin(M48T59_READ(M48T59_YEAR));
 81	/* tm_mon is 0-11 */
 82	tm->tm_mon	= bcd2bin(M48T59_READ(M48T59_MONTH)) - 1;
 83	tm->tm_mday	= bcd2bin(M48T59_READ(M48T59_MDAY));
 84
 85	val = M48T59_READ(M48T59_WDAY);
 86	if ((pdata->type == M48T59RTC_TYPE_M48T59) &&
 87	    (val & M48T59_WDAY_CEB) && (val & M48T59_WDAY_CB)) {
 88		dev_dbg(dev, "Century bit is enabled\n");
 89		tm->tm_year += 100;	/* one century */
 90	}
 91#ifdef CONFIG_SPARC
 92	/* Sun SPARC machines count years since 1968 */
 93	tm->tm_year += 68;
 94#endif
 95
 96	tm->tm_wday	= bcd2bin(val & 0x07);
 97	tm->tm_hour	= bcd2bin(M48T59_READ(M48T59_HOUR) & 0x3F);
 98	tm->tm_min	= bcd2bin(M48T59_READ(M48T59_MIN) & 0x7F);
 99	tm->tm_sec	= bcd2bin(M48T59_READ(M48T59_SEC) & 0x7F);
100
101	/* Clear the READ bit */
102	M48T59_CLEAR_BITS(M48T59_CNTL_READ, M48T59_CNTL);
103	spin_unlock_irqrestore(&m48t59->lock, flags);
104
105	dev_dbg(dev, "RTC read time %04d-%02d-%02d %02d/%02d/%02d\n",
106		tm->tm_year + 1900, tm->tm_mon, tm->tm_mday,
107		tm->tm_hour, tm->tm_min, tm->tm_sec);
108	return rtc_valid_tm(tm);
109}
110
111static int m48t59_rtc_set_time(struct device *dev, struct rtc_time *tm)
112{
113	struct platform_device *pdev = to_platform_device(dev);
114	struct m48t59_plat_data *pdata = pdev->dev.platform_data;
115	struct m48t59_private *m48t59 = platform_get_drvdata(pdev);
116	unsigned long flags;
117	u8 val = 0;
118	int year = tm->tm_year;
119
120#ifdef CONFIG_SPARC
121	/* Sun SPARC machines count years since 1968 */
122	year -= 68;
123#endif
124
125	dev_dbg(dev, "RTC set time %04d-%02d-%02d %02d/%02d/%02d\n",
126		year + 1900, tm->tm_mon, tm->tm_mday,
127		tm->tm_hour, tm->tm_min, tm->tm_sec);
128
129	if (year < 0)
130		return -EINVAL;
131
132	spin_lock_irqsave(&m48t59->lock, flags);
133	/* Issue the WRITE command */
134	M48T59_SET_BITS(M48T59_CNTL_WRITE, M48T59_CNTL);
135
136	M48T59_WRITE((bin2bcd(tm->tm_sec) & 0x7F), M48T59_SEC);
137	M48T59_WRITE((bin2bcd(tm->tm_min) & 0x7F), M48T59_MIN);
138	M48T59_WRITE((bin2bcd(tm->tm_hour) & 0x3F), M48T59_HOUR);
139	M48T59_WRITE((bin2bcd(tm->tm_mday) & 0x3F), M48T59_MDAY);
140	/* tm_mon is 0-11 */
141	M48T59_WRITE((bin2bcd(tm->tm_mon + 1) & 0x1F), M48T59_MONTH);
142	M48T59_WRITE(bin2bcd(year % 100), M48T59_YEAR);
143
144	if (pdata->type == M48T59RTC_TYPE_M48T59 && (year / 100))
145		val = (M48T59_WDAY_CEB | M48T59_WDAY_CB);
146	val |= (bin2bcd(tm->tm_wday) & 0x07);
147	M48T59_WRITE(val, M48T59_WDAY);
148
149	/* Clear the WRITE bit */
150	M48T59_CLEAR_BITS(M48T59_CNTL_WRITE, M48T59_CNTL);
151	spin_unlock_irqrestore(&m48t59->lock, flags);
152	return 0;
153}
154
155/*
156 * Read alarm time and date in RTC
157 */
158static int m48t59_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
159{
160	struct platform_device *pdev = to_platform_device(dev);
161	struct m48t59_plat_data *pdata = pdev->dev.platform_data;
162	struct m48t59_private *m48t59 = platform_get_drvdata(pdev);
163	struct rtc_time *tm = &alrm->time;
164	unsigned long flags;
165	u8 val;
166
167	/* If no irq, we don't support ALARM */
168	if (m48t59->irq == NO_IRQ)
169		return -EIO;
170
171	spin_lock_irqsave(&m48t59->lock, flags);
172	/* Issue the READ command */
173	M48T59_SET_BITS(M48T59_CNTL_READ, M48T59_CNTL);
174
175	tm->tm_year = bcd2bin(M48T59_READ(M48T59_YEAR));
176#ifdef CONFIG_SPARC
177	/* Sun SPARC machines count years since 1968 */
178	tm->tm_year += 68;
179#endif
180	/* tm_mon is 0-11 */
181	tm->tm_mon = bcd2bin(M48T59_READ(M48T59_MONTH)) - 1;
182
183	val = M48T59_READ(M48T59_WDAY);
184	if ((val & M48T59_WDAY_CEB) && (val & M48T59_WDAY_CB))
185		tm->tm_year += 100;	/* one century */
186
187	tm->tm_mday = bcd2bin(M48T59_READ(M48T59_ALARM_DATE));
188	tm->tm_hour = bcd2bin(M48T59_READ(M48T59_ALARM_HOUR));
189	tm->tm_min = bcd2bin(M48T59_READ(M48T59_ALARM_MIN));
190	tm->tm_sec = bcd2bin(M48T59_READ(M48T59_ALARM_SEC));
191
192	/* Clear the READ bit */
193	M48T59_CLEAR_BITS(M48T59_CNTL_READ, M48T59_CNTL);
194	spin_unlock_irqrestore(&m48t59->lock, flags);
195
196	dev_dbg(dev, "RTC read alarm time %04d-%02d-%02d %02d/%02d/%02d\n",
197		tm->tm_year + 1900, tm->tm_mon, tm->tm_mday,
198		tm->tm_hour, tm->tm_min, tm->tm_sec);
199	return rtc_valid_tm(tm);
200}
201
202/*
203 * Set alarm time and date in RTC
204 */
205static int m48t59_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
206{
207	struct platform_device *pdev = to_platform_device(dev);
208	struct m48t59_plat_data *pdata = pdev->dev.platform_data;
209	struct m48t59_private *m48t59 = platform_get_drvdata(pdev);
210	struct rtc_time *tm = &alrm->time;
211	u8 mday, hour, min, sec;
212	unsigned long flags;
213	int year = tm->tm_year;
214
215#ifdef CONFIG_SPARC
216	/* Sun SPARC machines count years since 1968 */
217	year -= 68;
218#endif
219
220	/* If no irq, we don't support ALARM */
221	if (m48t59->irq == NO_IRQ)
222		return -EIO;
223
224	if (year < 0)
225		return -EINVAL;
226
227	/*
228	 * 0xff means "always match"
229	 */
230	mday = tm->tm_mday;
231	mday = (mday >= 1 && mday <= 31) ? bin2bcd(mday) : 0xff;
232	if (mday == 0xff)
233		mday = M48T59_READ(M48T59_MDAY);
234
235	hour = tm->tm_hour;
236	hour = (hour < 24) ? bin2bcd(hour) : 0x00;
237
238	min = tm->tm_min;
239	min = (min < 60) ? bin2bcd(min) : 0x00;
240
241	sec = tm->tm_sec;
242	sec = (sec < 60) ? bin2bcd(sec) : 0x00;
243
244	spin_lock_irqsave(&m48t59->lock, flags);
245	/* Issue the WRITE command */
246	M48T59_SET_BITS(M48T59_CNTL_WRITE, M48T59_CNTL);
247
248	M48T59_WRITE(mday, M48T59_ALARM_DATE);
249	M48T59_WRITE(hour, M48T59_ALARM_HOUR);
250	M48T59_WRITE(min, M48T59_ALARM_MIN);
251	M48T59_WRITE(sec, M48T59_ALARM_SEC);
252
253	/* Clear the WRITE bit */
254	M48T59_CLEAR_BITS(M48T59_CNTL_WRITE, M48T59_CNTL);
255	spin_unlock_irqrestore(&m48t59->lock, flags);
256
257	dev_dbg(dev, "RTC set alarm time %04d-%02d-%02d %02d/%02d/%02d\n",
258		year + 1900, tm->tm_mon, tm->tm_mday,
259		tm->tm_hour, tm->tm_min, tm->tm_sec);
260	return 0;
261}
262
263/*
264 * Handle commands from user-space
265 */
266static int m48t59_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
267{
268	struct platform_device *pdev = to_platform_device(dev);
269	struct m48t59_plat_data *pdata = pdev->dev.platform_data;
270	struct m48t59_private *m48t59 = platform_get_drvdata(pdev);
271	unsigned long flags;
272
273	spin_lock_irqsave(&m48t59->lock, flags);
274	if (enabled)
275		M48T59_WRITE(M48T59_INTR_AFE, M48T59_INTR);
276	else
277		M48T59_WRITE(0x00, M48T59_INTR);
278	spin_unlock_irqrestore(&m48t59->lock, flags);
279
280	return 0;
281}
282
283static int m48t59_rtc_proc(struct device *dev, struct seq_file *seq)
284{
285	struct platform_device *pdev = to_platform_device(dev);
286	struct m48t59_plat_data *pdata = pdev->dev.platform_data;
287	struct m48t59_private *m48t59 = platform_get_drvdata(pdev);
288	unsigned long flags;
289	u8 val;
290
291	spin_lock_irqsave(&m48t59->lock, flags);
292	val = M48T59_READ(M48T59_FLAGS);
293	spin_unlock_irqrestore(&m48t59->lock, flags);
294
295	seq_printf(seq, "battery\t\t: %s\n",
296		 (val & M48T59_FLAGS_BF) ? "low" : "normal");
297	return 0;
298}
299
300/*
301 * IRQ handler for the RTC
302 */
303static irqreturn_t m48t59_rtc_interrupt(int irq, void *dev_id)
304{
305	struct device *dev = (struct device *)dev_id;
306	struct platform_device *pdev = to_platform_device(dev);
307	struct m48t59_plat_data *pdata = pdev->dev.platform_data;
308	struct m48t59_private *m48t59 = platform_get_drvdata(pdev);
309	u8 event;
310
311	spin_lock(&m48t59->lock);
312	event = M48T59_READ(M48T59_FLAGS);
313	spin_unlock(&m48t59->lock);
314
315	if (event & M48T59_FLAGS_AF) {
316		rtc_update_irq(m48t59->rtc, 1, (RTC_AF | RTC_IRQF));
317		return IRQ_HANDLED;
318	}
319
320	return IRQ_NONE;
321}
322
323static const struct rtc_class_ops m48t59_rtc_ops = {
324	.read_time	= m48t59_rtc_read_time,
325	.set_time	= m48t59_rtc_set_time,
326	.read_alarm	= m48t59_rtc_readalarm,
327	.set_alarm	= m48t59_rtc_setalarm,
328	.proc		= m48t59_rtc_proc,
329	.alarm_irq_enable = m48t59_rtc_alarm_irq_enable,
330};
331
332static const struct rtc_class_ops m48t02_rtc_ops = {
333	.read_time	= m48t59_rtc_read_time,
334	.set_time	= m48t59_rtc_set_time,
335};
336
337static ssize_t m48t59_nvram_read(struct file *filp, struct kobject *kobj,
338				struct bin_attribute *bin_attr,
339				char *buf, loff_t pos, size_t size)
340{
341	struct device *dev = container_of(kobj, struct device, kobj);
342	struct platform_device *pdev = to_platform_device(dev);
343	struct m48t59_plat_data *pdata = pdev->dev.platform_data;
344	struct m48t59_private *m48t59 = platform_get_drvdata(pdev);
345	ssize_t cnt = 0;
346	unsigned long flags;
 
347
348	for (; size > 0 && pos < pdata->offset; cnt++, size--) {
349		spin_lock_irqsave(&m48t59->lock, flags);
 
350		*buf++ = M48T59_READ(cnt);
351		spin_unlock_irqrestore(&m48t59->lock, flags);
352	}
353
354	return cnt;
 
 
355}
356
357static ssize_t m48t59_nvram_write(struct file *filp, struct kobject *kobj,
358				struct bin_attribute *bin_attr,
359				char *buf, loff_t pos, size_t size)
360{
361	struct device *dev = container_of(kobj, struct device, kobj);
362	struct platform_device *pdev = to_platform_device(dev);
363	struct m48t59_plat_data *pdata = pdev->dev.platform_data;
364	struct m48t59_private *m48t59 = platform_get_drvdata(pdev);
365	ssize_t cnt = 0;
366	unsigned long flags;
 
367
368	for (; size > 0 && pos < pdata->offset; cnt++, size--) {
369		spin_lock_irqsave(&m48t59->lock, flags);
 
370		M48T59_WRITE(*buf++, cnt);
371		spin_unlock_irqrestore(&m48t59->lock, flags);
372	}
373
374	return cnt;
 
 
375}
376
377static struct bin_attribute m48t59_nvram_attr = {
378	.attr = {
379		.name = "nvram",
380		.mode = S_IRUGO | S_IWUSR,
381	},
382	.read = m48t59_nvram_read,
383	.write = m48t59_nvram_write,
384};
385
386static int __devinit m48t59_rtc_probe(struct platform_device *pdev)
387{
388	struct m48t59_plat_data *pdata = pdev->dev.platform_data;
389	struct m48t59_private *m48t59 = NULL;
390	struct resource *res;
391	int ret = -ENOMEM;
392	char *name;
393	const struct rtc_class_ops *ops;
 
 
 
 
 
 
 
 
394
395	/* This chip could be memory-mapped or I/O-mapped */
396	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
397	if (!res) {
398		res = platform_get_resource(pdev, IORESOURCE_IO, 0);
399		if (!res)
400			return -EINVAL;
401	}
402
403	if (res->flags & IORESOURCE_IO) {
404		/* If we are I/O-mapped, the platform should provide
405		 * the operations accessing chip registers.
406		 */
407		if (!pdata || !pdata->write_byte || !pdata->read_byte)
408			return -EINVAL;
409	} else if (res->flags & IORESOURCE_MEM) {
410		/* we are memory-mapped */
411		if (!pdata) {
412			pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
 
413			if (!pdata)
414				return -ENOMEM;
415			/* Ensure we only kmalloc platform data once */
416			pdev->dev.platform_data = pdata;
417		}
418		if (!pdata->type)
419			pdata->type = M48T59RTC_TYPE_M48T59;
420
421		/* Try to use the generic memory read/write ops */
422		if (!pdata->write_byte)
423			pdata->write_byte = m48t59_mem_writeb;
424		if (!pdata->read_byte)
425			pdata->read_byte = m48t59_mem_readb;
426	}
427
428	m48t59 = kzalloc(sizeof(*m48t59), GFP_KERNEL);
429	if (!m48t59)
430		return -ENOMEM;
431
432	m48t59->ioaddr = pdata->ioaddr;
433
434	if (!m48t59->ioaddr) {
435		/* ioaddr not mapped externally */
436		m48t59->ioaddr = ioremap(res->start, resource_size(res));
 
437		if (!m48t59->ioaddr)
438			goto out;
439	}
440
441	/* Try to get irq number. We also can work in
442	 * the mode without IRQ.
443	 */
444	m48t59->irq = platform_get_irq(pdev, 0);
445	if (m48t59->irq <= 0)
446		m48t59->irq = NO_IRQ;
447
448	if (m48t59->irq != NO_IRQ) {
449		ret = request_irq(m48t59->irq, m48t59_rtc_interrupt,
450			IRQF_SHARED, "rtc-m48t59", &pdev->dev);
 
451		if (ret)
452			goto out;
453	}
454	switch (pdata->type) {
455	case M48T59RTC_TYPE_M48T59:
456		name = "m48t59";
457		ops = &m48t59_rtc_ops;
458		pdata->offset = 0x1ff0;
459		break;
460	case M48T59RTC_TYPE_M48T02:
461		name = "m48t02";
462		ops = &m48t02_rtc_ops;
463		pdata->offset = 0x7f0;
464		break;
465	case M48T59RTC_TYPE_M48T08:
466		name = "m48t08";
467		ops = &m48t02_rtc_ops;
468		pdata->offset = 0x1ff0;
469		break;
470	default:
471		dev_err(&pdev->dev, "Unknown RTC type\n");
472		ret = -ENODEV;
473		goto out;
474	}
475
476	spin_lock_init(&m48t59->lock);
477	platform_set_drvdata(pdev, m48t59);
478
479	m48t59->rtc = rtc_device_register(name, &pdev->dev, ops, THIS_MODULE);
480	if (IS_ERR(m48t59->rtc)) {
481		ret = PTR_ERR(m48t59->rtc);
482		goto out;
483	}
484
485	m48t59_nvram_attr.size = pdata->offset;
486
487	ret = sysfs_create_bin_file(&pdev->dev.kobj, &m48t59_nvram_attr);
488	if (ret) {
489		rtc_device_unregister(m48t59->rtc);
490		goto out;
491	}
 
 
492
493	return 0;
494
495out:
496	if (m48t59->irq != NO_IRQ)
497		free_irq(m48t59->irq, &pdev->dev);
498	if (m48t59->ioaddr)
499		iounmap(m48t59->ioaddr);
500		kfree(m48t59);
501	return ret;
502}
503
504static int __devexit m48t59_rtc_remove(struct platform_device *pdev)
505{
506	struct m48t59_private *m48t59 = platform_get_drvdata(pdev);
507	struct m48t59_plat_data *pdata = pdev->dev.platform_data;
508
509	sysfs_remove_bin_file(&pdev->dev.kobj, &m48t59_nvram_attr);
510	if (!IS_ERR(m48t59->rtc))
511		rtc_device_unregister(m48t59->rtc);
512	if (m48t59->ioaddr && !pdata->ioaddr)
513		iounmap(m48t59->ioaddr);
514	if (m48t59->irq != NO_IRQ)
515		free_irq(m48t59->irq, &pdev->dev);
516	platform_set_drvdata(pdev, NULL);
517	kfree(m48t59);
518	return 0;
519}
520
521/* work with hotplug and coldplug */
522MODULE_ALIAS("platform:rtc-m48t59");
523
524static struct platform_driver m48t59_rtc_driver = {
525	.driver		= {
526		.name	= "rtc-m48t59",
527		.owner	= THIS_MODULE,
528	},
529	.probe		= m48t59_rtc_probe,
530	.remove		= __devexit_p(m48t59_rtc_remove),
531};
532
533static int __init m48t59_rtc_init(void)
534{
535	return platform_driver_register(&m48t59_rtc_driver);
536}
537
538static void __exit m48t59_rtc_exit(void)
539{
540	platform_driver_unregister(&m48t59_rtc_driver);
541}
542
543module_init(m48t59_rtc_init);
544module_exit(m48t59_rtc_exit);
545
546MODULE_AUTHOR("Mark Zhan <rongkai.zhan@windriver.com>");
547MODULE_DESCRIPTION("M48T59/M48T02/M48T08 RTC driver");
548MODULE_LICENSE("GPL");