[thirdparty/kernel/stable.git] / drivers / rtc / rtc-pcf2123.c

/*
 * An SPI driver for the Philips PCF2123 RTC
 * Copyright 2009 Cyber Switching, Inc.
 *
 * Author: Chris Verges <chrisv@cyberswitching.com>
 * Maintainers: http://www.cyberswitching.com
 *
 * based on the RS5C348 driver in this same directory.
 *
 * Thanks to Christian Pellegrin <chripell@fsfe.org> for
 * the sysfs contributions to this driver.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Please note that the CS is active high, so platform data
 * should look something like:
 *
 * static struct spi_board_info ek_spi_devices[] = {
 * 	...
 * 	{
 * 		.modalias		= "rtc-pcf2123",
 * 		.chip_select		= 1,
 * 		.controller_data	= (void *)AT91_PIN_PA10,
 *		.max_speed_hz		= 1000 * 1000,
 *		.mode			= SPI_CS_HIGH,
 *		.bus_num		= 0,
 *	},
 *	...
 *};
 *
 */

#include <linux/bcd.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/rtc.h>
#include <linux/spi/spi.h>

#define DRV_VERSION "0.6"

#define PCF2123_REG_CTRL1	(0x00)	/* Control Register 1 */
#define PCF2123_REG_CTRL2	(0x01)	/* Control Register 2 */
#define PCF2123_REG_SC		(0x02)	/* datetime */
#define PCF2123_REG_MN		(0x03)
#define PCF2123_REG_HR		(0x04)
#define PCF2123_REG_DM		(0x05)
#define PCF2123_REG_DW		(0x06)
#define PCF2123_REG_MO		(0x07)
#define PCF2123_REG_YR		(0x08)

#define PCF2123_SUBADDR		(1 << 4)
#define PCF2123_WRITE		((0 << 7) | PCF2123_SUBADDR)
#define PCF2123_READ		((1 << 7) | PCF2123_SUBADDR)

static struct spi_driver pcf2123_driver;

struct pcf2123_sysfs_reg {
	struct device_attribute attr;
	char name[2];
};

struct pcf2123_plat_data {
	struct rtc_device *rtc;
	struct pcf2123_sysfs_reg regs[16];
};

/*
 * Causes a 30 nanosecond delay to ensure that the PCF2123 chip select
 * is released properly after an SPI write.  This function should be
 * called after EVERY read/write call over SPI.
 */
static inline void pcf2123_delay_trec(void)
{
	ndelay(30);
}

static ssize_t pcf2123_show(struct device *dev, struct device_attribute *attr,
			    char *buffer)
{
	struct spi_device *spi = to_spi_device(dev);
	struct pcf2123_sysfs_reg *r;
	u8 txbuf[1], rxbuf[1];
	unsigned long reg;
	int ret;

	r = container_of(attr, struct pcf2123_sysfs_reg, attr);

	if (strict_strtoul(r->name, 16, &reg))
		return -EINVAL;

	txbuf[0] = PCF2123_READ | reg;
	ret = spi_write_then_read(spi, txbuf, 1, rxbuf, 1);
	if (ret < 0)
		return -EIO;
	pcf2123_delay_trec();
	return sprintf(buffer, "0x%x\n", rxbuf[0]);
}

static ssize_t pcf2123_store(struct device *dev, struct device_attribute *attr,
			     const char *buffer, size_t count) {
	struct spi_device *spi = to_spi_device(dev);
	struct pcf2123_sysfs_reg *r;
	u8 txbuf[2];
	unsigned long reg;
	unsigned long val;

	int ret;

	r = container_of(attr, struct pcf2123_sysfs_reg, attr);

	if (strict_strtoul(r->name, 16, &reg)
		|| strict_strtoul(buffer, 10, &val))
		return -EINVAL;

	txbuf[0] = PCF2123_WRITE | reg;
	txbuf[1] = val;
	ret = spi_write(spi, txbuf, sizeof(txbuf));
	if (ret < 0)
		return -EIO;
	pcf2123_delay_trec();
	return count;
}

static int pcf2123_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
	struct spi_device *spi = to_spi_device(dev);
	u8 txbuf[1], rxbuf[7];
	int ret;

	txbuf[0] = PCF2123_READ | PCF2123_REG_SC;
	ret = spi_write_then_read(spi, txbuf, sizeof(txbuf),
			rxbuf, sizeof(rxbuf));
	if (ret < 0)
		return ret;
	pcf2123_delay_trec();

	tm->tm_sec = bcd2bin(rxbuf[0] & 0x7F);
	tm->tm_min = bcd2bin(rxbuf[1] & 0x7F);
	tm->tm_hour = bcd2bin(rxbuf[2] & 0x3F); /* rtc hr 0-23 */
	tm->tm_mday = bcd2bin(rxbuf[3] & 0x3F);
	tm->tm_wday = rxbuf[4] & 0x07;
	tm->tm_mon = bcd2bin(rxbuf[5] & 0x1F) - 1; /* rtc mn 1-12 */
	tm->tm_year = bcd2bin(rxbuf[6]);
	if (tm->tm_year < 70)
		tm->tm_year += 100;	/* assume we are in 1970...2069 */

	dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
			"mday=%d, mon=%d, year=%d, wday=%d\n",
			__func__,
			tm->tm_sec, tm->tm_min, tm->tm_hour,
			tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);

	/* the clock can give out invalid datetime, but we cannot return
	 * -EINVAL otherwise hwclock will refuse to set the time on bootup.
	 */
	if (rtc_valid_tm(tm) < 0)
		dev_err(dev, "retrieved date/time is not valid.\n");

	return 0;
}

static int pcf2123_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
	struct spi_device *spi = to_spi_device(dev);
	u8 txbuf[8];
	int ret;

	dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
			"mday=%d, mon=%d, year=%d, wday=%d\n",
			__func__,
			tm->tm_sec, tm->tm_min, tm->tm_hour,
			tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);

	/* Stop the counter first */
	txbuf[0] = PCF2123_WRITE | PCF2123_REG_CTRL1;
	txbuf[1] = 0x20;
	ret = spi_write(spi, txbuf, 2);
	if (ret < 0)
		return ret;
	pcf2123_delay_trec();

	/* Set the new time */
	txbuf[0] = PCF2123_WRITE | PCF2123_REG_SC;
	txbuf[1] = bin2bcd(tm->tm_sec & 0x7F);
	txbuf[2] = bin2bcd(tm->tm_min & 0x7F);
	txbuf[3] = bin2bcd(tm->tm_hour & 0x3F);
	txbuf[4] = bin2bcd(tm->tm_mday & 0x3F);
	txbuf[5] = tm->tm_wday & 0x07;
	txbuf[6] = bin2bcd((tm->tm_mon + 1) & 0x1F); /* rtc mn 1-12 */
	txbuf[7] = bin2bcd(tm->tm_year < 100 ? tm->tm_year : tm->tm_year - 100);

	ret = spi_write(spi, txbuf, sizeof(txbuf));
	if (ret < 0)
		return ret;
	pcf2123_delay_trec();

	/* Start the counter */
	txbuf[0] = PCF2123_WRITE | PCF2123_REG_CTRL1;
	txbuf[1] = 0x00;
	ret = spi_write(spi, txbuf, 2);
	if (ret < 0)
		return ret;
	pcf2123_delay_trec();

	return 0;
}

static const struct rtc_class_ops pcf2123_rtc_ops = {
	.read_time	= pcf2123_rtc_read_time,
	.set_time	= pcf2123_rtc_set_time,
};

static int __devinit pcf2123_probe(struct spi_device *spi)
{
	struct rtc_device *rtc;
	struct pcf2123_plat_data *pdata;
	u8 txbuf[2], rxbuf[2];
	int ret, i;

	pdata = kzalloc(sizeof(struct pcf2123_plat_data), GFP_KERNEL);
	if (!pdata)
		return -ENOMEM;
	spi->dev.platform_data = pdata;

	/* Send a software reset command */
	txbuf[0] = PCF2123_WRITE | PCF2123_REG_CTRL1;
	txbuf[1] = 0x58;
	dev_dbg(&spi->dev, "resetting RTC (0x%02X 0x%02X)\n",
			txbuf[0], txbuf[1]);
	ret = spi_write(spi, txbuf, 2 * sizeof(u8));
	if (ret < 0)
		goto kfree_exit;
	pcf2123_delay_trec();

	/* Stop the counter */
	txbuf[0] = PCF2123_WRITE | PCF2123_REG_CTRL1;
	txbuf[1] = 0x20;
	dev_dbg(&spi->dev, "stopping RTC (0x%02X 0x%02X)\n",
			txbuf[0], txbuf[1]);
	ret = spi_write(spi, txbuf, 2 * sizeof(u8));
	if (ret < 0)
		goto kfree_exit;
	pcf2123_delay_trec();

	/* See if the counter was actually stopped */
	txbuf[0] = PCF2123_READ | PCF2123_REG_CTRL1;
	dev_dbg(&spi->dev, "checking for presence of RTC (0x%02X)\n",
			txbuf[0]);
	ret = spi_write_then_read(spi, txbuf, 1 * sizeof(u8),
					rxbuf, 2 * sizeof(u8));
	dev_dbg(&spi->dev, "received data from RTC (0x%02X 0x%02X)\n",
			rxbuf[0], rxbuf[1]);
	if (ret < 0)
		goto kfree_exit;
	pcf2123_delay_trec();

	if (!(rxbuf[0] & 0x20)) {
		dev_err(&spi->dev, "chip not found\n");
		goto kfree_exit;
	}

	dev_info(&spi->dev, "chip found, driver version " DRV_VERSION "\n");
	dev_info(&spi->dev, "spiclk %u KHz.\n",
			(spi->max_speed_hz + 500) / 1000);

	/* Start the counter */
	txbuf[0] = PCF2123_WRITE | PCF2123_REG_CTRL1;
	txbuf[1] = 0x00;
	ret = spi_write(spi, txbuf, sizeof(txbuf));
	if (ret < 0)
		goto kfree_exit;
	pcf2123_delay_trec();

	/* Finalize the initialization */
	rtc = rtc_device_register(pcf2123_driver.driver.name, &spi->dev,
			&pcf2123_rtc_ops, THIS_MODULE);

	if (IS_ERR(rtc)) {
		dev_err(&spi->dev, "failed to register.\n");
		ret = PTR_ERR(rtc);
		goto kfree_exit;
	}

	pdata->rtc = rtc;

	for (i = 0; i < 16; i++) {
		sprintf(pdata->regs[i].name, "%1x", i);
		pdata->regs[i].attr.attr.mode = S_IRUGO | S_IWUSR;
		pdata->regs[i].attr.attr.name = pdata->regs[i].name;
		pdata->regs[i].attr.show = pcf2123_show;
		pdata->regs[i].attr.store = pcf2123_store;
		ret = device_create_file(&spi->dev, &pdata->regs[i].attr);
		if (ret) {
			dev_err(&spi->dev, "Unable to create sysfs %s\n",
				pdata->regs[i].name);
			goto sysfs_exit;
		}
	}

	return 0;

sysfs_exit:
	for (i--; i >= 0; i--)
		device_remove_file(&spi->dev, &pdata->regs[i].attr);

kfree_exit:
	kfree(pdata);
	spi->dev.platform_data = NULL;
	return ret;
}

static int __devexit pcf2123_remove(struct spi_device *spi)
{
	struct pcf2123_plat_data *pdata = spi->dev.platform_data;
	int i;

	if (pdata) {
		struct rtc_device *rtc = pdata->rtc;

		if (rtc)
			rtc_device_unregister(rtc);
		for (i = 0; i < 16; i++)
			if (pdata->regs[i].name[0])
				device_remove_file(&spi->dev,
						   &pdata->regs[i].attr);
		kfree(pdata);
	}

	return 0;
}

static struct spi_driver pcf2123_driver = {
	.driver	= {
			.name	= "rtc-pcf2123",
			.bus	= &spi_bus_type,
			.owner	= THIS_MODULE,
	},
	.probe	= pcf2123_probe,
	.remove	= __devexit_p(pcf2123_remove),
};

static int __init pcf2123_init(void)
{
	return spi_register_driver(&pcf2123_driver);
}

static void __exit pcf2123_exit(void)
{
	spi_unregister_driver(&pcf2123_driver);
}

MODULE_AUTHOR("Chris Verges <chrisv@cyberswitching.com>");
MODULE_DESCRIPTION("NXP PCF2123 RTC driver");
MODULE_LICENSE("GPL");
MODULE_VERSION(DRV_VERSION);

module_init(pcf2123_init);
module_exit(pcf2123_exit);
Commit	Line	Data
7f3923a1 CV	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/rtc.h>
	43	#include <linux/spi/spi.h>
	44
f3d2570a	45	#define DRV_VERSION "0.6"
7f3923a1 CV	46
	47	#define PCF2123_REG_CTRL1 (0x00) /* Control Register 1 */
	48	#define PCF2123_REG_CTRL2 (0x01) /* Control Register 2 */
	49	#define PCF2123_REG_SC (0x02) /* datetime */
	50	#define PCF2123_REG_MN (0x03)
	51	#define PCF2123_REG_HR (0x04)
	52	#define PCF2123_REG_DM (0x05)
	53	#define PCF2123_REG_DW (0x06)
	54	#define PCF2123_REG_MO (0x07)
	55	#define PCF2123_REG_YR (0x08)
	56
	57	#define PCF2123_SUBADDR (1 << 4)
	58	#define PCF2123_WRITE ((0 << 7) \| PCF2123_SUBADDR)
	59	#define PCF2123_READ ((1 << 7) \| PCF2123_SUBADDR)
	60
	61	static struct spi_driver pcf2123_driver;
	62
	63	struct pcf2123_sysfs_reg {
f3d2570a	64	struct device_attribute attr;
7f3923a1 CV	65	char name[2];
	66	};
	67
	68	struct pcf2123_plat_data {
	69	struct rtc_device *rtc;
	70	struct pcf2123_sysfs_reg regs[16];
	71	};
	72
	73	/*
	74	* Causes a 30 nanosecond delay to ensure that the PCF2123 chip select
	75	* is released properly after an SPI write. This function should be
	76	* called after EVERY read/write call over SPI.
	77	*/
	78	static inline void pcf2123_delay_trec(void)
	79	{
	80	ndelay(30);
	81	}
	82
	83	static ssize_t pcf2123_show(struct device dev, struct device_attribute attr,
	84	char *buffer)
	85	{
	86	struct spi_device *spi = to_spi_device(dev);
f3d2570a	87	struct pcf2123_sysfs_reg *r;
7f3923a1	88	u8 txbuf[1], rxbuf[1];
f3d2570a	89	unsigned long reg;
7f3923a1 CV	90	int ret;
7f3923a1 CV	91
f3d2570a CV	92	r = container_of(attr, struct pcf2123_sysfs_reg, attr);
	93
	94	if (strict_strtoul(r->name, 16, &reg))
	95	return -EINVAL;
	96
	97	txbuf[0] = PCF2123_READ \| reg;
7f3923a1 CV	98	ret = spi_write_then_read(spi, txbuf, 1, rxbuf, 1);
7f3923a1 CV	99	if (ret < 0)
f3d2570a	100	return -EIO;
7f3923a1	101	pcf2123_delay_trec();
f3d2570a	102	return sprintf(buffer, "0x%x\n", rxbuf[0]);
7f3923a1 CV	103	}
	104
	105	static ssize_t pcf2123_store(struct device dev, struct device_attribute attr,
	106	const char *buffer, size_t count) {
	107	struct spi_device *spi = to_spi_device(dev);
f3d2570a	108	struct pcf2123_sysfs_reg *r;
7f3923a1	109	u8 txbuf[2];
f3d2570a CV	110	unsigned long reg;
	111	unsigned long val;
	112
7f3923a1 CV	113	int ret;
7f3923a1 CV	114
f3d2570a CV	115	r = container_of(attr, struct pcf2123_sysfs_reg, attr);
	116
	117	if (strict_strtoul(r->name, 16, &reg)
	118	\|\| strict_strtoul(buffer, 10, &val))
	119	return -EINVAL;
	120
	121	txbuf[0] = PCF2123_WRITE \| reg;
	122	txbuf[1] = val;
7f3923a1 CV	123	ret = spi_write(spi, txbuf, sizeof(txbuf));
	124	if (ret < 0)
	125	return -EIO;
	126	pcf2123_delay_trec();
	127	return count;
	128	}
	129
	130	static int pcf2123_rtc_read_time(struct device dev, struct rtc_time tm)
	131	{
	132	struct spi_device *spi = to_spi_device(dev);
	133	u8 txbuf[1], rxbuf[7];
	134	int ret;
	135
	136	txbuf[0] = PCF2123_READ \| PCF2123_REG_SC;
	137	ret = spi_write_then_read(spi, txbuf, sizeof(txbuf),
	138	rxbuf, sizeof(rxbuf));
	139	if (ret < 0)
	140	return ret;
	141	pcf2123_delay_trec();
	142
	143	tm->tm_sec = bcd2bin(rxbuf[0] & 0x7F);
	144	tm->tm_min = bcd2bin(rxbuf[1] & 0x7F);
	145	tm->tm_hour = bcd2bin(rxbuf[2] & 0x3F); /* rtc hr 0-23 */
	146	tm->tm_mday = bcd2bin(rxbuf[3] & 0x3F);
	147	tm->tm_wday = rxbuf[4] & 0x07;
	148	tm->tm_mon = bcd2bin(rxbuf[5] & 0x1F) - 1; /* rtc mn 1-12 */
	149	tm->tm_year = bcd2bin(rxbuf[6]);
	150	if (tm->tm_year < 70)
	151	tm->tm_year += 100; /* assume we are in 1970...2069 */
	152
	153	dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
	154	"mday=%d, mon=%d, year=%d, wday=%d\n",
	155	__func__,
	156	tm->tm_sec, tm->tm_min, tm->tm_hour,
	157	tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
	158
	159	/* the clock can give out invalid datetime, but we cannot return
	160	* -EINVAL otherwise hwclock will refuse to set the time on bootup.
	161	*/
	162	if (rtc_valid_tm(tm) < 0)
	163	dev_err(dev, "retrieved date/time is not valid.\n");
	164
	165	return 0;
	166	}
	167
	168	static int pcf2123_rtc_set_time(struct device dev, struct rtc_time tm)
	169	{
	170	struct spi_device *spi = to_spi_device(dev);
	171	u8 txbuf[8];
	172	int ret;
	173
	174	dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
	175	"mday=%d, mon=%d, year=%d, wday=%d\n",
	176	__func__,
	177	tm->tm_sec, tm->tm_min, tm->tm_hour,
	178	tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
	179
	180	/* Stop the counter first */
	181	txbuf[0] = PCF2123_WRITE \| PCF2123_REG_CTRL1;
	182	txbuf[1] = 0x20;
	183	ret = spi_write(spi, txbuf, 2);
	184	if (ret < 0)
	185	return ret;
	186	pcf2123_delay_trec();
187
188	/* Set the new time */
189	txbuf[0] = PCF2123_WRITE \| PCF2123_REG_SC;
190	txbuf[1] = bin2bcd(tm->tm_sec & 0x7F);
191	txbuf[2] = bin2bcd(tm->tm_min & 0x7F);
192	txbuf[3] = bin2bcd(tm->tm_hour & 0x3F);
193	txbuf[4] = bin2bcd(tm->tm_mday & 0x3F);
194	txbuf[5] = tm->tm_wday & 0x07;
195	txbuf[6] = bin2bcd((tm->tm_mon + 1) & 0x1F); /* rtc mn 1-12 */
196	txbuf[7] = bin2bcd(tm->tm_year < 100 ? tm->tm_year : tm->tm_year - 100);
197
198	ret = spi_write(spi, txbuf, sizeof(txbuf));
199	if (ret < 0)
200	return ret;
201	pcf2123_delay_trec();
202
203	/* Start the counter */
204	txbuf[0] = PCF2123_WRITE \| PCF2123_REG_CTRL1;
205	txbuf[1] = 0x00;
206	ret = spi_write(spi, txbuf, 2);
207	if (ret < 0)
208	return ret;
209	pcf2123_delay_trec();
210
211	return 0;
212	}
213
214	static const struct rtc_class_ops pcf2123_rtc_ops = {
215	.read_time = pcf2123_rtc_read_time,
216	.set_time = pcf2123_rtc_set_time,
217	};
218
219	static int __devinit pcf2123_probe(struct spi_device *spi)
220	{
221	struct rtc_device *rtc;
222	struct pcf2123_plat_data *pdata;
223	u8 txbuf[2], rxbuf[2];
224	int ret, i;
225
226	pdata = kzalloc(sizeof(struct pcf2123_plat_data), GFP_KERNEL);
227	if (!pdata)
228	return -ENOMEM;
229	spi->dev.platform_data = pdata;
230
231	/* Send a software reset command */
232	txbuf[0] = PCF2123_WRITE \| PCF2123_REG_CTRL1;
233	txbuf[1] = 0x58;
234	dev_dbg(&spi->dev, "resetting RTC (0x%02X 0x%02X)\n",
235	txbuf[0], txbuf[1]);
236	ret = spi_write(spi, txbuf, 2 * sizeof(u8));
237	if (ret < 0)
f3d2570a	238	goto kfree_exit;
7f3923a1 CV	239	pcf2123_delay_trec();
	240
	241	/* Stop the counter */
	242	txbuf[0] = PCF2123_WRITE \| PCF2123_REG_CTRL1;
	243	txbuf[1] = 0x20;
	244	dev_dbg(&spi->dev, "stopping RTC (0x%02X 0x%02X)\n",
	245	txbuf[0], txbuf[1]);
	246	ret = spi_write(spi, txbuf, 2 * sizeof(u8));
	247	if (ret < 0)
f3d2570a	248	goto kfree_exit;
7f3923a1 CV	249	pcf2123_delay_trec();
	250
	251	/* See if the counter was actually stopped */
	252	txbuf[0] = PCF2123_READ \| PCF2123_REG_CTRL1;
	253	dev_dbg(&spi->dev, "checking for presence of RTC (0x%02X)\n",
	254	txbuf[0]);
	255	ret = spi_write_then_read(spi, txbuf, 1 * sizeof(u8),
	256	rxbuf, 2 * sizeof(u8));
	257	dev_dbg(&spi->dev, "received data from RTC (0x%02X 0x%02X)\n",
	258	rxbuf[0], rxbuf[1]);
	259	if (ret < 0)
	260	goto kfree_exit;
	261	pcf2123_delay_trec();
	262
	263	if (!(rxbuf[0] & 0x20)) {
	264	dev_err(&spi->dev, "chip not found\n");
	265	goto kfree_exit;
	266	}
	267
	268	dev_info(&spi->dev, "chip found, driver version " DRV_VERSION "\n");
	269	dev_info(&spi->dev, "spiclk %u KHz.\n",
	270	(spi->max_speed_hz + 500) / 1000);
	271
	272	/* Start the counter */
	273	txbuf[0] = PCF2123_WRITE \| PCF2123_REG_CTRL1;
	274	txbuf[1] = 0x00;
	275	ret = spi_write(spi, txbuf, sizeof(txbuf));
	276	if (ret < 0)
	277	goto kfree_exit;
	278	pcf2123_delay_trec();
	279
	280	/* Finalize the initialization */
	281	rtc = rtc_device_register(pcf2123_driver.driver.name, &spi->dev,
	282	&pcf2123_rtc_ops, THIS_MODULE);
	283
	284	if (IS_ERR(rtc)) {
	285	dev_err(&spi->dev, "failed to register.\n");
	286	ret = PTR_ERR(rtc);
	287	goto kfree_exit;
	288	}
	289
	290	pdata->rtc = rtc;
	291
	292	for (i = 0; i < 16; i++) {
	293	sprintf(pdata->regs[i].name, "%1x", i);
	294	pdata->regs[i].attr.attr.mode = S_IRUGO \| S_IWUSR;
	295	pdata->regs[i].attr.attr.name = pdata->regs[i].name;
	296	pdata->regs[i].attr.show = pcf2123_show;
	297	pdata->regs[i].attr.store = pcf2123_store;
	298	ret = device_create_file(&spi->dev, &pdata->regs[i].attr);
	299	if (ret) {
	300	dev_err(&spi->dev, "Unable to create sysfs %s\n",
	301	pdata->regs[i].name);
f3d2570a	302	goto sysfs_exit;
7f3923a1 CV	303	}
	304	}
	305
	306	return 0;
f3d2570a CV	307
	308	sysfs_exit:
	309	for (i--; i >= 0; i--)
	310	device_remove_file(&spi->dev, &pdata->regs[i].attr);
	311
7f3923a1 CV	312	kfree_exit:
	313	kfree(pdata);
	314	spi->dev.platform_data = NULL;
	315	return ret;
	316	}
	317
b51e8293	318	static int __devexit pcf2123_remove(struct spi_device *spi)
7f3923a1 CV	319	{
	320	struct pcf2123_plat_data *pdata = spi->dev.platform_data;
	321	int i;
	322
	323	if (pdata) {
	324	struct rtc_device *rtc = pdata->rtc;
	325
	326	if (rtc)
	327	rtc_device_unregister(rtc);
	328	for (i = 0; i < 16; i++)
	329	if (pdata->regs[i].name[0])
	330	device_remove_file(&spi->dev,
	331	&pdata->regs[i].attr);
	332	kfree(pdata);
	333	}
	334
	335	return 0;
	336	}
	337
	338	static struct spi_driver pcf2123_driver = {
	339	.driver = {
	340	.name = "rtc-pcf2123",
	341	.bus = &spi_bus_type,
	342	.owner = THIS_MODULE,
	343	},
	344	.probe = pcf2123_probe,
	345	.remove = __devexit_p(pcf2123_remove),
	346	};
	347
	348	static int __init pcf2123_init(void)
	349	{
	350	return spi_register_driver(&pcf2123_driver);
	351	}
	352
	353	static void __exit pcf2123_exit(void)
	354	{
	355	spi_unregister_driver(&pcf2123_driver);
	356	}
	357
	358	MODULE_AUTHOR("Chris Verges <chrisv@cyberswitching.com>");
	359	MODULE_DESCRIPTION("NXP PCF2123 RTC driver");
	360	MODULE_LICENSE("GPL");
	361	MODULE_VERSION(DRV_VERSION);
	362
	363	module_init(pcf2123_init);
	364	module_exit(pcf2123_exit);