1/*
  2 * An SPI driver for the Philips PCF2123 RTC
  3 * Copyright 2009 Cyber Switching, Inc.
  4 *
  5 * Author: Chris Verges <chrisv@cyberswitching.com>
  6 * Maintainers: http://www.cyberswitching.com
  7 *
  8 * based on the RS5C348 driver in this same directory.
  9 *
 10 * Thanks to Christian Pellegrin <chripell@fsfe.org> for
 11 * the sysfs contributions to this driver.
 12 *
 13 * This program is free software; you can redistribute it and/or modify
 14 * it under the terms of the GNU General Public License version 2 as
 15 * published by the Free Software Foundation.
 16 *
 17 * Please note that the CS is active high, so platform data
 18 * should look something like:
 19 *
 20 * static struct spi_board_info ek_spi_devices[] = {
 21 * 	...
 22 * 	{
 23 * 		.modalias		= "rtc-pcf2123",
 24 * 		.chip_select		= 1,
 25 * 		.controller_data	= (void *)AT91_PIN_PA10,
 26 *		.max_speed_hz		= 1000 * 1000,
 27 *		.mode			= SPI_CS_HIGH,
 28 *		.bus_num		= 0,
 29 *	},
 30 *	...
 31 *};
 32 *
 33 */
 34
 35#include <linux/bcd.h>
 36#include <linux/delay.h>
 37#include <linux/device.h>
 38#include <linux/errno.h>
 39#include <linux/init.h>
 40#include <linux/kernel.h>
 41#include <linux/string.h>
 42#include <linux/slab.h>
 43#include <linux/rtc.h>
 44#include <linux/spi/spi.h>
 45#include <linux/module.h>
 
 46
 47#define DRV_VERSION "0.6"
 48
 49#define PCF2123_REG_CTRL1	(0x00)	/* Control Register 1 */
 50#define PCF2123_REG_CTRL2	(0x01)	/* Control Register 2 */
 51#define PCF2123_REG_SC		(0x02)	/* datetime */
 52#define PCF2123_REG_MN		(0x03)
 53#define PCF2123_REG_HR		(0x04)
 54#define PCF2123_REG_DM		(0x05)
 55#define PCF2123_REG_DW		(0x06)
 56#define PCF2123_REG_MO		(0x07)
 57#define PCF2123_REG_YR		(0x08)
 58
 59#define PCF2123_SUBADDR		(1 << 4)
 60#define PCF2123_WRITE		((0 << 7) | PCF2123_SUBADDR)
 61#define PCF2123_READ		((1 << 7) | PCF2123_SUBADDR)
 62
 63static struct spi_driver pcf2123_driver;
 64
 65struct pcf2123_sysfs_reg {
 66	struct device_attribute attr;
 67	char name[2];
 68};
 69
 70struct pcf2123_plat_data {
 71	struct rtc_device *rtc;
 72	struct pcf2123_sysfs_reg regs[16];
 73};
 74
 75/*
 76 * Causes a 30 nanosecond delay to ensure that the PCF2123 chip select
 77 * is released properly after an SPI write.  This function should be
 78 * called after EVERY read/write call over SPI.
 79 */
 80static inline void pcf2123_delay_trec(void)
 81{
 82	ndelay(30);
 83}
 84
 85static ssize_t pcf2123_show(struct device *dev, struct device_attribute *attr,
 86			    char *buffer)
 87{
 88	struct spi_device *spi = to_spi_device(dev);
 89	struct pcf2123_sysfs_reg *r;
 90	u8 txbuf[1], rxbuf[1];
 91	unsigned long reg;
 92	int ret;
 93
 94	r = container_of(attr, struct pcf2123_sysfs_reg, attr);
 95
 96	if (strict_strtoul(r->name, 16, &reg))
 97		return -EINVAL;
 
 98
 99	txbuf[0] = PCF2123_READ | reg;
100	ret = spi_write_then_read(spi, txbuf, 1, rxbuf, 1);
101	if (ret < 0)
102		return -EIO;
103	pcf2123_delay_trec();
104	return sprintf(buffer, "0x%x\n", rxbuf[0]);
105}
106
107static ssize_t pcf2123_store(struct device *dev, struct device_attribute *attr,
108			     const char *buffer, size_t count) {
109	struct spi_device *spi = to_spi_device(dev);
110	struct pcf2123_sysfs_reg *r;
111	u8 txbuf[2];
112	unsigned long reg;
113	unsigned long val;
114
115	int ret;
116
117	r = container_of(attr, struct pcf2123_sysfs_reg, attr);
118
119	if (strict_strtoul(r->name, 16, &reg)
120		|| strict_strtoul(buffer, 10, &val))
121		return -EINVAL;
 
 
 
 
122
123	txbuf[0] = PCF2123_WRITE | reg;
124	txbuf[1] = val;
125	ret = spi_write(spi, txbuf, sizeof(txbuf));
126	if (ret < 0)
127		return -EIO;
128	pcf2123_delay_trec();
129	return count;
130}
131
132static int pcf2123_rtc_read_time(struct device *dev, struct rtc_time *tm)
133{
134	struct spi_device *spi = to_spi_device(dev);
135	u8 txbuf[1], rxbuf[7];
136	int ret;
137
138	txbuf[0] = PCF2123_READ | PCF2123_REG_SC;
139	ret = spi_write_then_read(spi, txbuf, sizeof(txbuf),
140			rxbuf, sizeof(rxbuf));
141	if (ret < 0)
142		return ret;
143	pcf2123_delay_trec();
144
145	tm->tm_sec = bcd2bin(rxbuf[0] & 0x7F);
146	tm->tm_min = bcd2bin(rxbuf[1] & 0x7F);
147	tm->tm_hour = bcd2bin(rxbuf[2] & 0x3F); /* rtc hr 0-23 */
148	tm->tm_mday = bcd2bin(rxbuf[3] & 0x3F);
149	tm->tm_wday = rxbuf[4] & 0x07;
150	tm->tm_mon = bcd2bin(rxbuf[5] & 0x1F) - 1; /* rtc mn 1-12 */
151	tm->tm_year = bcd2bin(rxbuf[6]);
152	if (tm->tm_year < 70)
153		tm->tm_year += 100;	/* assume we are in 1970...2069 */
154
155	dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
156			"mday=%d, mon=%d, year=%d, wday=%d\n",
157			__func__,
158			tm->tm_sec, tm->tm_min, tm->tm_hour,
159			tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
160
161	/* the clock can give out invalid datetime, but we cannot return
162	 * -EINVAL otherwise hwclock will refuse to set the time on bootup.
163	 */
164	if (rtc_valid_tm(tm) < 0)
165		dev_err(dev, "retrieved date/time is not valid.\n");
166
167	return 0;
168}
169
170static int pcf2123_rtc_set_time(struct device *dev, struct rtc_time *tm)
171{
172	struct spi_device *spi = to_spi_device(dev);
173	u8 txbuf[8];
174	int ret;
175
176	dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
177			"mday=%d, mon=%d, year=%d, wday=%d\n",
178			__func__,
179			tm->tm_sec, tm->tm_min, tm->tm_hour,
180			tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
181
182	/* Stop the counter first */
183	txbuf[0] = PCF2123_WRITE | PCF2123_REG_CTRL1;
184	txbuf[1] = 0x20;
185	ret = spi_write(spi, txbuf, 2);
186	if (ret < 0)
187		return ret;
188	pcf2123_delay_trec();
189
190	/* Set the new time */
191	txbuf[0] = PCF2123_WRITE | PCF2123_REG_SC;
192	txbuf[1] = bin2bcd(tm->tm_sec & 0x7F);
193	txbuf[2] = bin2bcd(tm->tm_min & 0x7F);
194	txbuf[3] = bin2bcd(tm->tm_hour & 0x3F);
195	txbuf[4] = bin2bcd(tm->tm_mday & 0x3F);
196	txbuf[5] = tm->tm_wday & 0x07;
197	txbuf[6] = bin2bcd((tm->tm_mon + 1) & 0x1F); /* rtc mn 1-12 */
198	txbuf[7] = bin2bcd(tm->tm_year < 100 ? tm->tm_year : tm->tm_year - 100);
199
200	ret = spi_write(spi, txbuf, sizeof(txbuf));
201	if (ret < 0)
202		return ret;
203	pcf2123_delay_trec();
204
205	/* Start the counter */
206	txbuf[0] = PCF2123_WRITE | PCF2123_REG_CTRL1;
207	txbuf[1] = 0x00;
208	ret = spi_write(spi, txbuf, 2);
209	if (ret < 0)
210		return ret;
211	pcf2123_delay_trec();
212
213	return 0;
214}
215
216static const struct rtc_class_ops pcf2123_rtc_ops = {
217	.read_time	= pcf2123_rtc_read_time,
218	.set_time	= pcf2123_rtc_set_time,
219};
220
221static int __devinit pcf2123_probe(struct spi_device *spi)
222{
223	struct rtc_device *rtc;
224	struct pcf2123_plat_data *pdata;
225	u8 txbuf[2], rxbuf[2];
226	int ret, i;
227
228	pdata = kzalloc(sizeof(struct pcf2123_plat_data), GFP_KERNEL);
 
229	if (!pdata)
230		return -ENOMEM;
231	spi->dev.platform_data = pdata;
232
233	/* Send a software reset command */
234	txbuf[0] = PCF2123_WRITE | PCF2123_REG_CTRL1;
235	txbuf[1] = 0x58;
236	dev_dbg(&spi->dev, "resetting RTC (0x%02X 0x%02X)\n",
237			txbuf[0], txbuf[1]);
238	ret = spi_write(spi, txbuf, 2 * sizeof(u8));
239	if (ret < 0)
240		goto kfree_exit;
241	pcf2123_delay_trec();
242
243	/* Stop the counter */
244	txbuf[0] = PCF2123_WRITE | PCF2123_REG_CTRL1;
245	txbuf[1] = 0x20;
246	dev_dbg(&spi->dev, "stopping RTC (0x%02X 0x%02X)\n",
247			txbuf[0], txbuf[1]);
248	ret = spi_write(spi, txbuf, 2 * sizeof(u8));
249	if (ret < 0)
250		goto kfree_exit;
251	pcf2123_delay_trec();
252
253	/* See if the counter was actually stopped */
254	txbuf[0] = PCF2123_READ | PCF2123_REG_CTRL1;
255	dev_dbg(&spi->dev, "checking for presence of RTC (0x%02X)\n",
256			txbuf[0]);
257	ret = spi_write_then_read(spi, txbuf, 1 * sizeof(u8),
258					rxbuf, 2 * sizeof(u8));
259	dev_dbg(&spi->dev, "received data from RTC (0x%02X 0x%02X)\n",
260			rxbuf[0], rxbuf[1]);
261	if (ret < 0)
262		goto kfree_exit;
263	pcf2123_delay_trec();
264
265	if (!(rxbuf[0] & 0x20)) {
266		dev_err(&spi->dev, "chip not found\n");
 
267		goto kfree_exit;
268	}
269
270	dev_info(&spi->dev, "chip found, driver version " DRV_VERSION "\n");
271	dev_info(&spi->dev, "spiclk %u KHz.\n",
272			(spi->max_speed_hz + 500) / 1000);
273
274	/* Start the counter */
275	txbuf[0] = PCF2123_WRITE | PCF2123_REG_CTRL1;
276	txbuf[1] = 0x00;
277	ret = spi_write(spi, txbuf, sizeof(txbuf));
278	if (ret < 0)
279		goto kfree_exit;
280	pcf2123_delay_trec();
281
282	/* Finalize the initialization */
283	rtc = rtc_device_register(pcf2123_driver.driver.name, &spi->dev,
284			&pcf2123_rtc_ops, THIS_MODULE);
285
286	if (IS_ERR(rtc)) {
287		dev_err(&spi->dev, "failed to register.\n");
288		ret = PTR_ERR(rtc);
289		goto kfree_exit;
290	}
291
292	pdata->rtc = rtc;
293
294	for (i = 0; i < 16; i++) {
 
295		sprintf(pdata->regs[i].name, "%1x", i);
296		pdata->regs[i].attr.attr.mode = S_IRUGO | S_IWUSR;
297		pdata->regs[i].attr.attr.name = pdata->regs[i].name;
298		pdata->regs[i].attr.show = pcf2123_show;
299		pdata->regs[i].attr.store = pcf2123_store;
300		ret = device_create_file(&spi->dev, &pdata->regs[i].attr);
301		if (ret) {
302			dev_err(&spi->dev, "Unable to create sysfs %s\n",
303				pdata->regs[i].name);
304			goto sysfs_exit;
305		}
306	}
307
308	return 0;
309
310sysfs_exit:
311	for (i--; i >= 0; i--)
312		device_remove_file(&spi->dev, &pdata->regs[i].attr);
313
314kfree_exit:
315	kfree(pdata);
316	spi->dev.platform_data = NULL;
317	return ret;
318}
319
320static int __devexit pcf2123_remove(struct spi_device *spi)
321{
322	struct pcf2123_plat_data *pdata = spi->dev.platform_data;
323	int i;
324
325	if (pdata) {
326		struct rtc_device *rtc = pdata->rtc;
327
328		if (rtc)
329			rtc_device_unregister(rtc);
330		for (i = 0; i < 16; i++)
331			if (pdata->regs[i].name[0])
332				device_remove_file(&spi->dev,
333						   &pdata->regs[i].attr);
334		kfree(pdata);
335	}
336
337	return 0;
338}
339
340static struct spi_driver pcf2123_driver = {
341	.driver	= {
342			.name	= "rtc-pcf2123",
343			.owner	= THIS_MODULE,
344	},
345	.probe	= pcf2123_probe,
346	.remove	= __devexit_p(pcf2123_remove),
347};
348
349module_spi_driver(pcf2123_driver);
350
351MODULE_AUTHOR("Chris Verges <chrisv@cyberswitching.com>");
352MODULE_DESCRIPTION("NXP PCF2123 RTC driver");
353MODULE_LICENSE("GPL");
354MODULE_VERSION(DRV_VERSION);

  1/*
  2 * An SPI driver for the Philips PCF2123 RTC
  3 * Copyright 2009 Cyber Switching, Inc.
  4 *
  5 * Author: Chris Verges <chrisv@cyberswitching.com>
  6 * Maintainers: http://www.cyberswitching.com
  7 *
  8 * based on the RS5C348 driver in this same directory.
  9 *
 10 * Thanks to Christian Pellegrin <chripell@fsfe.org> for
 11 * the sysfs contributions to this driver.
 12 *
 13 * This program is free software; you can redistribute it and/or modify
 14 * it under the terms of the GNU General Public License version 2 as
 15 * published by the Free Software Foundation.
 16 *
 17 * Please note that the CS is active high, so platform data
 18 * should look something like:
 19 *
 20 * static struct spi_board_info ek_spi_devices[] = {
 21 *	...
 22 *	{
 23 *		.modalias		= "rtc-pcf2123",
 24 *		.chip_select		= 1,
 25 *		.controller_data	= (void *)AT91_PIN_PA10,
 26 *		.max_speed_hz		= 1000 * 1000,
 27 *		.mode			= SPI_CS_HIGH,
 28 *		.bus_num		= 0,
 29 *	},
 30 *	...
 31 *};
 32 *
 33 */
 34
 35#include <linux/bcd.h>
 36#include <linux/delay.h>
 37#include <linux/device.h>
 38#include <linux/errno.h>
 39#include <linux/init.h>
 40#include <linux/kernel.h>
 41#include <linux/string.h>
 42#include <linux/slab.h>
 43#include <linux/rtc.h>
 44#include <linux/spi/spi.h>
 45#include <linux/module.h>
 46#include <linux/sysfs.h>
 47
 48#define DRV_VERSION "0.6"
 49
 50#define PCF2123_REG_CTRL1	(0x00)	/* Control Register 1 */
 51#define PCF2123_REG_CTRL2	(0x01)	/* Control Register 2 */
 52#define PCF2123_REG_SC		(0x02)	/* datetime */
 53#define PCF2123_REG_MN		(0x03)
 54#define PCF2123_REG_HR		(0x04)
 55#define PCF2123_REG_DM		(0x05)
 56#define PCF2123_REG_DW		(0x06)
 57#define PCF2123_REG_MO		(0x07)
 58#define PCF2123_REG_YR		(0x08)
 59
 60#define PCF2123_SUBADDR		(1 << 4)
 61#define PCF2123_WRITE		((0 << 7) | PCF2123_SUBADDR)
 62#define PCF2123_READ		((1 << 7) | PCF2123_SUBADDR)
 63
 64static struct spi_driver pcf2123_driver;
 65
 66struct pcf2123_sysfs_reg {
 67	struct device_attribute attr;
 68	char name[2];
 69};
 70
 71struct pcf2123_plat_data {
 72	struct rtc_device *rtc;
 73	struct pcf2123_sysfs_reg regs[16];
 74};
 75
 76/*
 77 * Causes a 30 nanosecond delay to ensure that the PCF2123 chip select
 78 * is released properly after an SPI write.  This function should be
 79 * called after EVERY read/write call over SPI.
 80 */
 81static inline void pcf2123_delay_trec(void)
 82{
 83	ndelay(30);
 84}
 85
 86static ssize_t pcf2123_show(struct device *dev, struct device_attribute *attr,
 87			    char *buffer)
 88{
 89	struct spi_device *spi = to_spi_device(dev);
 90	struct pcf2123_sysfs_reg *r;
 91	u8 txbuf[1], rxbuf[1];
 92	unsigned long reg;
 93	int ret;
 94
 95	r = container_of(attr, struct pcf2123_sysfs_reg, attr);
 96
 97	ret = kstrtoul(r->name, 16, &reg);
 98	if (ret)
 99		return ret;
100
101	txbuf[0] = PCF2123_READ | reg;
102	ret = spi_write_then_read(spi, txbuf, 1, rxbuf, 1);
103	if (ret < 0)
104		return -EIO;
105	pcf2123_delay_trec();
106	return sprintf(buffer, "0x%x\n", rxbuf[0]);
107}
108
109static ssize_t pcf2123_store(struct device *dev, struct device_attribute *attr,
110			     const char *buffer, size_t count) {
111	struct spi_device *spi = to_spi_device(dev);
112	struct pcf2123_sysfs_reg *r;
113	u8 txbuf[2];
114	unsigned long reg;
115	unsigned long val;
116
117	int ret;
118
119	r = container_of(attr, struct pcf2123_sysfs_reg, attr);
120
121	ret = kstrtoul(r->name, 16, &reg);
122	if (ret)
123		return ret;
124
125	ret = kstrtoul(buffer, 10, &val);
126	if (ret)
127		return ret;
128
129	txbuf[0] = PCF2123_WRITE | reg;
130	txbuf[1] = val;
131	ret = spi_write(spi, txbuf, sizeof(txbuf));
132	if (ret < 0)
133		return -EIO;
134	pcf2123_delay_trec();
135	return count;
136}
137
138static int pcf2123_rtc_read_time(struct device *dev, struct rtc_time *tm)
139{
140	struct spi_device *spi = to_spi_device(dev);
141	u8 txbuf[1], rxbuf[7];
142	int ret;
143
144	txbuf[0] = PCF2123_READ | PCF2123_REG_SC;
145	ret = spi_write_then_read(spi, txbuf, sizeof(txbuf),
146			rxbuf, sizeof(rxbuf));
147	if (ret < 0)
148		return ret;
149	pcf2123_delay_trec();
150
151	tm->tm_sec = bcd2bin(rxbuf[0] & 0x7F);
152	tm->tm_min = bcd2bin(rxbuf[1] & 0x7F);
153	tm->tm_hour = bcd2bin(rxbuf[2] & 0x3F); /* rtc hr 0-23 */
154	tm->tm_mday = bcd2bin(rxbuf[3] & 0x3F);
155	tm->tm_wday = rxbuf[4] & 0x07;
156	tm->tm_mon = bcd2bin(rxbuf[5] & 0x1F) - 1; /* rtc mn 1-12 */
157	tm->tm_year = bcd2bin(rxbuf[6]);
158	if (tm->tm_year < 70)
159		tm->tm_year += 100;	/* assume we are in 1970...2069 */
160
161	dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
162			"mday=%d, mon=%d, year=%d, wday=%d\n",
163			__func__,
164			tm->tm_sec, tm->tm_min, tm->tm_hour,
165			tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
166
167	/* the clock can give out invalid datetime, but we cannot return
168	 * -EINVAL otherwise hwclock will refuse to set the time on bootup.
169	 */
170	if (rtc_valid_tm(tm) < 0)
171		dev_err(dev, "retrieved date/time is not valid.\n");
172
173	return 0;
174}
175
176static int pcf2123_rtc_set_time(struct device *dev, struct rtc_time *tm)
177{
178	struct spi_device *spi = to_spi_device(dev);
179	u8 txbuf[8];
180	int ret;
181
182	dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
183			"mday=%d, mon=%d, year=%d, wday=%d\n",
184			__func__,
185			tm->tm_sec, tm->tm_min, tm->tm_hour,
186			tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
187
188	/* Stop the counter first */
189	txbuf[0] = PCF2123_WRITE | PCF2123_REG_CTRL1;
190	txbuf[1] = 0x20;
191	ret = spi_write(spi, txbuf, 2);
192	if (ret < 0)
193		return ret;
194	pcf2123_delay_trec();
195
196	/* Set the new time */
197	txbuf[0] = PCF2123_WRITE | PCF2123_REG_SC;
198	txbuf[1] = bin2bcd(tm->tm_sec & 0x7F);
199	txbuf[2] = bin2bcd(tm->tm_min & 0x7F);
200	txbuf[3] = bin2bcd(tm->tm_hour & 0x3F);
201	txbuf[4] = bin2bcd(tm->tm_mday & 0x3F);
202	txbuf[5] = tm->tm_wday & 0x07;
203	txbuf[6] = bin2bcd((tm->tm_mon + 1) & 0x1F); /* rtc mn 1-12 */
204	txbuf[7] = bin2bcd(tm->tm_year < 100 ? tm->tm_year : tm->tm_year - 100);
205
206	ret = spi_write(spi, txbuf, sizeof(txbuf));
207	if (ret < 0)
208		return ret;
209	pcf2123_delay_trec();
210
211	/* Start the counter */
212	txbuf[0] = PCF2123_WRITE | PCF2123_REG_CTRL1;
213	txbuf[1] = 0x00;
214	ret = spi_write(spi, txbuf, 2);
215	if (ret < 0)
216		return ret;
217	pcf2123_delay_trec();
218
219	return 0;
220}
221
222static const struct rtc_class_ops pcf2123_rtc_ops = {
223	.read_time	= pcf2123_rtc_read_time,
224	.set_time	= pcf2123_rtc_set_time,
225};
226
227static int pcf2123_probe(struct spi_device *spi)
228{
229	struct rtc_device *rtc;
230	struct pcf2123_plat_data *pdata;
231	u8 txbuf[2], rxbuf[2];
232	int ret, i;
233
234	pdata = devm_kzalloc(&spi->dev, sizeof(struct pcf2123_plat_data),
235				GFP_KERNEL);
236	if (!pdata)
237		return -ENOMEM;
238	spi->dev.platform_data = pdata;
239
240	/* Send a software reset command */
241	txbuf[0] = PCF2123_WRITE | PCF2123_REG_CTRL1;
242	txbuf[1] = 0x58;
243	dev_dbg(&spi->dev, "resetting RTC (0x%02X 0x%02X)\n",
244			txbuf[0], txbuf[1]);
245	ret = spi_write(spi, txbuf, 2 * sizeof(u8));
246	if (ret < 0)
247		goto kfree_exit;
248	pcf2123_delay_trec();
249
250	/* Stop the counter */
251	txbuf[0] = PCF2123_WRITE | PCF2123_REG_CTRL1;
252	txbuf[1] = 0x20;
253	dev_dbg(&spi->dev, "stopping RTC (0x%02X 0x%02X)\n",
254			txbuf[0], txbuf[1]);
255	ret = spi_write(spi, txbuf, 2 * sizeof(u8));
256	if (ret < 0)
257		goto kfree_exit;
258	pcf2123_delay_trec();
259
260	/* See if the counter was actually stopped */
261	txbuf[0] = PCF2123_READ | PCF2123_REG_CTRL1;
262	dev_dbg(&spi->dev, "checking for presence of RTC (0x%02X)\n",
263			txbuf[0]);
264	ret = spi_write_then_read(spi, txbuf, 1 * sizeof(u8),
265					rxbuf, 2 * sizeof(u8));
266	dev_dbg(&spi->dev, "received data from RTC (0x%02X 0x%02X)\n",
267			rxbuf[0], rxbuf[1]);
268	if (ret < 0)
269		goto kfree_exit;
270	pcf2123_delay_trec();
271
272	if (!(rxbuf[0] & 0x20)) {
273		dev_err(&spi->dev, "chip not found\n");
274		ret = -ENODEV;
275		goto kfree_exit;
276	}
277
278	dev_info(&spi->dev, "chip found, driver version " DRV_VERSION "\n");
279	dev_info(&spi->dev, "spiclk %u KHz.\n",
280			(spi->max_speed_hz + 500) / 1000);
281
282	/* Start the counter */
283	txbuf[0] = PCF2123_WRITE | PCF2123_REG_CTRL1;
284	txbuf[1] = 0x00;
285	ret = spi_write(spi, txbuf, sizeof(txbuf));
286	if (ret < 0)
287		goto kfree_exit;
288	pcf2123_delay_trec();
289
290	/* Finalize the initialization */
291	rtc = devm_rtc_device_register(&spi->dev, pcf2123_driver.driver.name,
292			&pcf2123_rtc_ops, THIS_MODULE);
293
294	if (IS_ERR(rtc)) {
295		dev_err(&spi->dev, "failed to register.\n");
296		ret = PTR_ERR(rtc);
297		goto kfree_exit;
298	}
299
300	pdata->rtc = rtc;
301
302	for (i = 0; i < 16; i++) {
303		sysfs_attr_init(&pdata->regs[i].attr.attr);
304		sprintf(pdata->regs[i].name, "%1x", i);
305		pdata->regs[i].attr.attr.mode = S_IRUGO | S_IWUSR;
306		pdata->regs[i].attr.attr.name = pdata->regs[i].name;
307		pdata->regs[i].attr.show = pcf2123_show;
308		pdata->regs[i].attr.store = pcf2123_store;
309		ret = device_create_file(&spi->dev, &pdata->regs[i].attr);
310		if (ret) {
311			dev_err(&spi->dev, "Unable to create sysfs %s\n",
312				pdata->regs[i].name);
313			goto sysfs_exit;
314		}
315	}
316
317	return 0;
318
319sysfs_exit:
320	for (i--; i >= 0; i--)
321		device_remove_file(&spi->dev, &pdata->regs[i].attr);
322
323kfree_exit:
 
324	spi->dev.platform_data = NULL;
325	return ret;
326}
327
328static int pcf2123_remove(struct spi_device *spi)
329{
330	struct pcf2123_plat_data *pdata = dev_get_platdata(&spi->dev);
331	int i;
332
333	if (pdata) {
 
 
 
 
334		for (i = 0; i < 16; i++)
335			if (pdata->regs[i].name[0])
336				device_remove_file(&spi->dev,
337						   &pdata->regs[i].attr);
 
338	}
339
340	return 0;
341}
342
343static struct spi_driver pcf2123_driver = {
344	.driver	= {
345			.name	= "rtc-pcf2123",
346			.owner	= THIS_MODULE,
347	},
348	.probe	= pcf2123_probe,
349	.remove	= pcf2123_remove,
350};
351
352module_spi_driver(pcf2123_driver);
353
354MODULE_AUTHOR("Chris Verges <chrisv@cyberswitching.com>");
355MODULE_DESCRIPTION("NXP PCF2123 RTC driver");
356MODULE_LICENSE("GPL");
357MODULE_VERSION(DRV_VERSION);