1 files changed, 254 insertions, 92 deletions

diff --git a/drivers/i2c/chips/m41t00.c b/drivers/i2c/chips/m41t00.c
index 99ab4ec..2dd0a34 100644
--- a/drivers/i2c/chips/m41t00.c
+++ b/drivers/i2c/chips/m41t00.c
@@ -1,11 +1,9 @@
 /*
- * drivers/i2c/chips/m41t00.c
- *
- * I2C client/driver for the ST M41T00 Real-Time Clock chip.
+ * I2C client/driver for the ST M41T00 family of i2c rtc chips.
  *
  * Author: Mark A. Greer <mgreer@mvista.com>
  *
- * 2005 (c) MontaVista Software, Inc. This file is licensed under
+ * 2005, 2006 (c) MontaVista Software, Inc. This file is licensed under
  * the terms of the GNU General Public License version 2. This program
  * is licensed "as is" without any warranty of any kind, whether express
  * or implied.
@@ -13,9 +11,6 @@
 /*
  * This i2c client/driver wedges between the drivers/char/genrtc.c RTC
  * interface and the SMBus interface of the i2c subsystem.
- * It would be more efficient to use i2c msgs/i2c_transfer directly but, as
- * recommened in .../Documentation/i2c/writing-clients section
- * "Sending and receiving", using SMBus level communication is preferred.
  */
 
 #include <linux/kernel.h>
@@ -24,56 +19,110 @@
 #include <linux/i2c.h>
 #include <linux/rtc.h>
 #include <linux/bcd.h>
-#include <linux/mutex.h>
 #include <linux/workqueue.h>
-
+#include <linux/platform_device.h>
+#include <linux/m41t00.h>
 #include <asm/time.h>
 #include <asm/rtc.h>
 
-#define	M41T00_DRV_NAME		"m41t00"
-
-static DEFINE_MUTEX(m41t00_mutex);
-
 static struct i2c_driver m41t00_driver;
 static struct i2c_client *save_client;
 
 static unsigned short ignore[] = { I2C_CLIENT_END };
-static unsigned short normal_addr[] = { 0x68, I2C_CLIENT_END };
+static unsigned short normal_addr[] = { I2C_CLIENT_END, I2C_CLIENT_END };
 
 static struct i2c_client_address_data addr_data = {
-	.normal_i2c		= normal_addr,
-	.probe			= ignore,
-	.ignore			= ignore,
+	.normal_i2c	= normal_addr,
+	.probe		= ignore,
+	.ignore		= ignore,
+};
+
+struct m41t00_chip_info {
+	u8	type;
+	char	*name;
+	u8	read_limit;
+	u8	sec;		/* Offsets for chip regs */
+	u8	min;
+	u8	hour;
+	u8	day;
+	u8	mon;
+	u8	year;
+	u8	alarm_mon;
+	u8	alarm_hour;
+	u8	sqw;
+	u8	sqw_freq;
 };
 
+static struct m41t00_chip_info m41t00_chip_info_tbl[] = {
+	{
+		.type		= M41T00_TYPE_M41T00,
+		.name		= "m41t00",
+		.read_limit	= 5,
+		.sec		= 0,
+		.min		= 1,
+		.hour		= 2,
+		.day		= 4,
+		.mon		= 5,
+		.year		= 6,
+	},
+	{
+		.type		= M41T00_TYPE_M41T81,
+		.name		= "m41t81",
+		.read_limit	= 1,
+		.sec		= 1,
+		.min		= 2,
+		.hour		= 3,
+		.day		= 5,
+		.mon		= 6,
+		.year		= 7,
+		.alarm_mon	= 0xa,
+		.alarm_hour	= 0xc,
+		.sqw		= 0x13,
+	},
+	{
+		.type		= M41T00_TYPE_M41T85,
+		.name		= "m41t85",
+		.read_limit	= 1,
+		.sec		= 1,
+		.min		= 2,
+		.hour		= 3,
+		.day		= 5,
+		.mon		= 6,
+		.year		= 7,
+		.alarm_mon	= 0xa,
+		.alarm_hour	= 0xc,
+		.sqw		= 0x13,
+	},
+};
+static struct m41t00_chip_info *m41t00_chip;
+
 ulong
 m41t00_get_rtc_time(void)
 {
-	s32	sec, min, hour, day, mon, year;
-	s32	sec1, min1, hour1, day1, mon1, year1;
-	ulong	limit = 10;
+	s32 sec, min, hour, day, mon, year;
+	s32 sec1, min1, hour1, day1, mon1, year1;
+	u8 reads = 0;
+	u8 buf[8], msgbuf[1] = { 0 }; /* offset into rtc's regs */
+	struct i2c_msg msgs[] = {
+		{
+			.addr	= save_client->addr,
+			.flags	= 0,
+			.len	= 1,
+			.buf	= msgbuf,
+		},
+		{
+			.addr	= save_client->addr,
+			.flags	= I2C_M_RD,
+			.len	= 8,
+			.buf	= buf,
+		},
+	};
 
 	sec = min = hour = day = mon = year = 0;
-	sec1 = min1 = hour1 = day1 = mon1 = year1 = 0;
 
-	mutex_lock(&m41t00_mutex);
 	do {
-		if (((sec = i2c_smbus_read_byte_data(save_client, 0)) >= 0)
-			&& ((min = i2c_smbus_read_byte_data(save_client, 1))
-				>= 0)
-			&& ((hour = i2c_smbus_read_byte_data(save_client, 2))
-				>= 0)
-			&& ((day = i2c_smbus_read_byte_data(save_client, 4))
-				>= 0)
-			&& ((mon = i2c_smbus_read_byte_data(save_client, 5))
-				>= 0)
-			&& ((year = i2c_smbus_read_byte_data(save_client, 6))
-				>= 0)
-			&& ((sec == sec1) && (min == min1) && (hour == hour1)
-				&& (day == day1) && (mon == mon1)
-				&& (year == year1)))
-
-				break;
+		if (i2c_transfer(save_client->adapter, msgs, 2) < 0)
+			goto read_err;
 
 		sec1 = sec;
 		min1 = min;
@@ -81,69 +130,88 @@ m41t00_get_rtc_time(void)
 		day1 = day;
 		mon1 = mon;
 		year1 = year;
-	} while (--limit > 0);
-	mutex_unlock(&m41t00_mutex);
-
-	if (limit == 0) {
-		dev_warn(&save_client->dev,
-			"m41t00: can't read rtc chip\n");
-		sec = min = hour = day = mon = year = 0;
-	}
-
-	sec &= 0x7f;
-	min &= 0x7f;
-	hour &= 0x3f;
-	day &= 0x3f;
-	mon &= 0x1f;
-	year &= 0xff;
 
-	BCD_TO_BIN(sec);
-	BCD_TO_BIN(min);
-	BCD_TO_BIN(hour);
-	BCD_TO_BIN(day);
-	BCD_TO_BIN(mon);
-	BCD_TO_BIN(year);
+		sec = buf[m41t00_chip->sec] & 0x7f;
+		min = buf[m41t00_chip->min] & 0x7f;
+		hour = buf[m41t00_chip->hour] & 0x3f;
+		day = buf[m41t00_chip->day] & 0x3f;
+		mon = buf[m41t00_chip->mon] & 0x1f;
+		year = buf[m41t00_chip->year];
+	} while ((++reads < m41t00_chip->read_limit) && ((sec != sec1)
+			|| (min != min1) || (hour != hour1) || (day != day1)
+			|| (mon != mon1) || (year != year1)));
+
+	if ((m41t00_chip->read_limit > 1) && ((sec != sec1) || (min != min1)
+			|| (hour != hour1) || (day != day1) || (mon != mon1)
+			|| (year != year1)))
+		goto read_err;
+
+	sec = BCD2BIN(sec);
+	min = BCD2BIN(min);
+	hour = BCD2BIN(hour);
+	day = BCD2BIN(day);
+	mon = BCD2BIN(mon);
+	year = BCD2BIN(year);
 
 	year += 1900;
 	if (year < 1970)
 		year += 100;
 
 	return mktime(year, mon, day, hour, min, sec);
+
+read_err:
+	dev_err(&save_client->dev, "m41t00_get_rtc_time: Read error\n");
+	return 0;
 }
+EXPORT_SYMBOL_GPL(m41t00_get_rtc_time);
 
 static void
 m41t00_set(void *arg)
 {
 	struct rtc_time	tm;
-	ulong	nowtime = *(ulong *)arg;
+	int nowtime = *(int *)arg;
+	s32 sec, min, hour, day, mon, year;
+	u8 wbuf[9], *buf = &wbuf[1], msgbuf[1] = { 0 };
+	struct i2c_msg msgs[] = {
+		{
+			.addr	= save_client->addr,
+			.flags	= 0,
+			.len	= 1,
+			.buf	= msgbuf,
+		},
+		{
+			.addr	= save_client->addr,
+			.flags	= I2C_M_RD,
+			.len	= 8,
+			.buf	= buf,
+		},
+	};
 
 	to_tm(nowtime, &tm);
 	tm.tm_year = (tm.tm_year - 1900) % 100;
 
-	BIN_TO_BCD(tm.tm_sec);
-	BIN_TO_BCD(tm.tm_min);
-	BIN_TO_BCD(tm.tm_hour);
-	BIN_TO_BCD(tm.tm_mon);
-	BIN_TO_BCD(tm.tm_mday);
-	BIN_TO_BCD(tm.tm_year);
-
-	mutex_lock(&m41t00_mutex);
-	if ((i2c_smbus_write_byte_data(save_client, 0, tm.tm_sec & 0x7f) < 0)
-		|| (i2c_smbus_write_byte_data(save_client, 1, tm.tm_min & 0x7f)
-			< 0)
-		|| (i2c_smbus_write_byte_data(save_client, 2, tm.tm_hour & 0x3f)
-			< 0)
-		|| (i2c_smbus_write_byte_data(save_client, 4, tm.tm_mday & 0x3f)
-			< 0)
-		|| (i2c_smbus_write_byte_data(save_client, 5, tm.tm_mon & 0x1f)
-			< 0)
-		|| (i2c_smbus_write_byte_data(save_client, 6, tm.tm_year & 0xff)
-			< 0))
-
-		dev_warn(&save_client->dev,"m41t00: can't write to rtc chip\n");
-
-	mutex_unlock(&m41t00_mutex);
-	return;
+	sec = BIN2BCD(tm.tm_sec);
+	min = BIN2BCD(tm.tm_min);
+	hour = BIN2BCD(tm.tm_hour);
+	day = BIN2BCD(tm.tm_mday);
+	mon = BIN2BCD(tm.tm_mon);
+	year = BIN2BCD(tm.tm_year);
+
+	/* Read reg values into buf[0..7]/wbuf[1..8] */
+	if (i2c_transfer(save_client->adapter, msgs, 2) < 0) {
+		dev_err(&save_client->dev, "m41t00_set: Read error\n");
+		return;
+	}
+
+	wbuf[0] = 0; /* offset into rtc's regs */
+	buf[m41t00_chip->sec] = (buf[m41t00_chip->sec] & ~0x7f) | (sec & 0x7f);
+	buf[m41t00_chip->min] = (buf[m41t00_chip->min] & ~0x7f) | (min & 0x7f);
+	buf[m41t00_chip->hour] = (buf[m41t00_chip->hour] & ~0x3f) | (hour& 0x3f);
+	buf[m41t00_chip->day] = (buf[m41t00_chip->day] & ~0x3f) | (day & 0x3f);
+	buf[m41t00_chip->mon] = (buf[m41t00_chip->mon] & ~0x1f) | (mon & 0x1f);
+
+	if (i2c_master_send(save_client, wbuf, 9) < 0)
+		dev_err(&save_client->dev, "m41t00_set: Write error\n");
 }
 
 static ulong new_time;
@@ -162,6 +230,48 @@ m41t00_set_rtc_time(ulong nowtime)
 
 	return 0;
 }
+EXPORT_SYMBOL_GPL(m41t00_set_rtc_time);
+
+/*
+ *****************************************************************************
+ *
+ *	platform_data Driver Interface
+ *
+ *****************************************************************************
+ */
+static int __init
+m41t00_platform_probe(struct platform_device *pdev)
+{
+	struct m41t00_platform_data *pdata;
+	int i;
+
+	if (pdev && (pdata = pdev->dev.platform_data)) {
+		normal_addr[0] = pdata->i2c_addr;
+
+		for (i=0; i<ARRAY_SIZE(m41t00_chip_info_tbl); i++)
+			if (m41t00_chip_info_tbl[i].type == pdata->type) {
+				m41t00_chip = &m41t00_chip_info_tbl[i];
+				m41t00_chip->sqw_freq = pdata->sqw_freq;
+				return 0;
+			}
+	}
+	return -ENODEV;
+}
+
+static int __exit
+m41t00_platform_remove(struct platform_device *pdev)
+{
+	return 0;
+}
+
+static struct platform_driver m41t00_platform_driver = {
+	.probe  = m41t00_platform_probe,
+	.remove = m41t00_platform_remove,
+	.driver = {
+		.owner = THIS_MODULE,
+		.name  = M41T00_DRV_NAME,
+	},
+};
 
 /*
  *****************************************************************************
@@ -176,23 +286,71 @@ m41t00_probe(struct i2c_adapter *adap, int addr, int kind)
 	struct i2c_client *client;
 	int rc;
 
+	if (!i2c_check_functionality(adap, I2C_FUNC_I2C
+			| I2C_FUNC_SMBUS_BYTE_DATA))
+		return 0;
+
 	client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL);
 	if (!client)
 		return -ENOMEM;
 
-	strncpy(client->name, M41T00_DRV_NAME, I2C_NAME_SIZE);
+	strlcpy(client->name, m41t00_chip->name, I2C_NAME_SIZE);
 	client->addr = addr;
 	client->adapter = adap;
 	client->driver = &m41t00_driver;
 
-	if ((rc = i2c_attach_client(client)) != 0) {
-		kfree(client);
-		return rc;
+	if ((rc = i2c_attach_client(client)))
+		goto attach_err;
+
+	if (m41t00_chip->type != M41T00_TYPE_M41T00) {
+		/* If asked, disable SQW, set SQW frequency & re-enable */
+		if (m41t00_chip->sqw_freq)
+			if (((rc = i2c_smbus_read_byte_data(client,
+					m41t00_chip->alarm_mon)) < 0)
+			 || ((rc = i2c_smbus_write_byte_data(client,
+					m41t00_chip->alarm_mon, rc & ~0x40)) <0)
+			 || ((rc = i2c_smbus_write_byte_data(client,
+					m41t00_chip->sqw,
+					m41t00_chip->sqw_freq)) < 0)
+			 || ((rc = i2c_smbus_write_byte_data(client,
+					m41t00_chip->alarm_mon, rc | 0x40)) <0))
+				goto sqw_err;
+
+		/* Make sure HT (Halt Update) bit is cleared */
+		if ((rc = i2c_smbus_read_byte_data(client,
+				m41t00_chip->alarm_hour)) < 0)
+			goto ht_err;
+
+		if (rc & 0x40)
+			if ((rc = i2c_smbus_write_byte_data(client,
+					m41t00_chip->alarm_hour, rc & ~0x40))<0)
+				goto ht_err;
 	}
 
-	m41t00_wq = create_singlethread_workqueue("m41t00");
+	/* Make sure ST (stop) bit is cleared */
+	if ((rc = i2c_smbus_read_byte_data(client, m41t00_chip->sec)) < 0)
+		goto st_err;
+
+	if (rc & 0x80)
+		if ((rc = i2c_smbus_write_byte_data(client, m41t00_chip->sec,
+				rc & ~0x80)) < 0)
+			goto st_err;
+
+	m41t00_wq = create_singlethread_workqueue(m41t00_chip->name);
 	save_client = client;
 	return 0;
+
+st_err:
+	dev_err(&client->dev, "m41t00_probe: Can't clear ST bit\n");
+	goto attach_err;
+ht_err:
+	dev_err(&client->dev, "m41t00_probe: Can't clear HT bit\n");
+	goto attach_err;
+sqw_err:
+	dev_err(&client->dev, "m41t00_probe: Can't set SQW Frequency\n");
+attach_err:
+	kfree(client);
+	return rc;
 }
 
 static int
@@ -204,7 +362,7 @@ m41t00_attach(struct i2c_adapter *adap)
 static int
 m41t00_detach(struct i2c_client *client)
 {
-	int	rc;
+	int rc;
 
 	if ((rc = i2c_detach_client(client)) == 0) {
 		kfree(client);
@@ -225,14 +383,18 @@ static struct i2c_driver m41t00_driver = {
 static int __init
 m41t00_init(void)
 {
-	return i2c_add_driver(&m41t00_driver);
+	int rc;
+
+	if (!(rc = platform_driver_register(&m41t00_platform_driver)))
+		rc = i2c_add_driver(&m41t00_driver);
+	return rc;
 }
 
 static void __exit
 m41t00_exit(void)
 {
 	i2c_del_driver(&m41t00_driver);
-	return;
+	platform_driver_unregister(&m41t00_platform_driver);
 }
 
 module_init(m41t00_init);