From 6fea6ca2a40cb08ba483df938243344d5dc4b420 Mon Sep 17 00:00:00 2001
From: David Anders <danders.dev@gmail.com>
Date: Wed, 2 Nov 2011 13:37:53 -0700
Subject: [PATCH] --- yaml --- r: 273233 b: refs/heads/master c:
 43fcb81550f7a16be192b19c77a379c9b27b1585 h: refs/heads/master i:   273231:
 1f7efcae4da6a3e9c55d465deab6ad8532f94cf3 v: v3

---
 [refs]                         |  2 +-
 trunk/drivers/rtc/rtc-ds1307.c | 27 +++++++++++++++++++++++++++
 2 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index 570f32f49223..f29609c218be 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 6d03d06db8881f4f9da87d5c77234b98c40a30e9
+refs/heads/master: 43fcb81550f7a16be192b19c77a379c9b27b1585
diff --git a/trunk/drivers/rtc/rtc-ds1307.c b/trunk/drivers/rtc/rtc-ds1307.c
index b2005b44e4f7..62b0763b7b9a 100644
--- a/trunk/drivers/rtc/rtc-ds1307.c
+++ b/trunk/drivers/rtc/rtc-ds1307.c
@@ -34,6 +34,7 @@ enum ds_type {
 	ds_1388,
 	ds_3231,
 	m41t00,
+	mcp7941x,
 	rx_8025,
 	// rs5c372 too?  different address...
 };
@@ -43,6 +44,7 @@ enum ds_type {
 #define DS1307_REG_SECS		0x00	/* 00-59 */
 #	define DS1307_BIT_CH		0x80
 #	define DS1340_BIT_nEOSC		0x80
+#	define MCP7941X_BIT_ST		0x80
 #define DS1307_REG_MIN		0x01	/* 00-59 */
 #define DS1307_REG_HOUR		0x02	/* 00-23, or 1-12{am,pm} */
 #	define DS1307_BIT_12HR		0x40	/* in REG_HOUR */
@@ -50,6 +52,7 @@ enum ds_type {
 #	define DS1340_BIT_CENTURY_EN	0x80	/* in REG_HOUR */
 #	define DS1340_BIT_CENTURY	0x40	/* in REG_HOUR */
 #define DS1307_REG_WDAY		0x03	/* 01-07 */
+#	define MCP7941X_BIT_VBATEN	0x08
 #define DS1307_REG_MDAY		0x04	/* 01-31 */
 #define DS1307_REG_MONTH	0x05	/* 01-12 */
 #	define DS1337_BIT_CENTURY	0x80	/* in REG_MONTH */
@@ -137,6 +140,8 @@ static const struct chip_desc chips[] = {
 },
 [m41t00] = {
 },
+[mcp7941x] = {
+},
 [rx_8025] = {
 }, };
 
@@ -149,6 +154,7 @@ static const struct i2c_device_id ds1307_id[] = {
 	{ "ds1340", ds_1340 },
 	{ "ds3231", ds_3231 },
 	{ "m41t00", m41t00 },
+	{ "mcp7941x", mcp7941x },
 	{ "pt7c4338", ds_1307 },
 	{ "rx8025", rx_8025 },
 	{ }
@@ -365,6 +371,10 @@ static int ds1307_set_time(struct device *dev, struct rtc_time *t)
 		buf[DS1307_REG_HOUR] |= DS1340_BIT_CENTURY_EN
 				| DS1340_BIT_CENTURY;
 		break;
+	case mcp7941x:
+		buf[DS1307_REG_SECS] |= MCP7941X_BIT_ST;
+		buf[DS1307_REG_WDAY] |= MCP7941X_BIT_VBATEN;
+		break;
 	default:
 		break;
 	}
@@ -808,6 +818,23 @@ static int __devinit ds1307_probe(struct i2c_client *client,
 			i2c_smbus_write_byte_data(client, DS1340_REG_FLAG, 0);
 			dev_warn(&client->dev, "SET TIME!\n");
 		}
+		break;
+	case mcp7941x:
+		/* make sure that the backup battery is enabled */
+		if (!(ds1307->regs[DS1307_REG_WDAY] & MCP7941X_BIT_VBATEN)) {
+			i2c_smbus_write_byte_data(client, DS1307_REG_WDAY,
+					ds1307->regs[DS1307_REG_WDAY]
+					| MCP7941X_BIT_VBATEN);
+		}
+
+		/* clock halted?  turn it on, so clock can tick. */
+		if (!(tmp & MCP7941X_BIT_ST)) {
+			i2c_smbus_write_byte_data(client, DS1307_REG_SECS,
+					MCP7941X_BIT_ST);
+			dev_warn(&client->dev, "SET TIME!\n");
+			goto read_rtc;
+		}
+
 		break;
 	case rx_8025:
 	case ds_1337: