X-Git-Url: https://git.karo-electronics.de/?a=blobdiff_plain;f=drivers%2Frtc%2Frtc-ds1307.c;h=8e1c5cb6ece6f60619e5cafcea4271e056d96778;hb=2161a2a644a6d33a29d68395518d103ed805758f;hp=821d9c089cdb48a40a244d1c18ab912d6f0b9432;hpb=3c9a6793bde1feb368cd6ef113c08a40a37f7517;p=karo-tx-linux.git

diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c
index 821d9c089cdb..8e1c5cb6ece6 100644
--- a/drivers/rtc/rtc-ds1307.c
+++ b/drivers/rtc/rtc-ds1307.c
@@ -482,11 +482,6 @@ static int ds1337_read_alarm(struct device *dev, struct rtc_wkalrm *t)
 	t->time.tm_min = bcd2bin(ds1307->regs[1] & 0x7f);
 	t->time.tm_hour = bcd2bin(ds1307->regs[2] & 0x3f);
 	t->time.tm_mday = bcd2bin(ds1307->regs[3] & 0x3f);
-	t->time.tm_mon = -1;
-	t->time.tm_year = -1;
-	t->time.tm_wday = -1;
-	t->time.tm_yday = -1;
-	t->time.tm_isdst = -1;
 
 	/* ... and status */
 	t->enabled = !!(ds1307->regs[7] & DS1337_BIT_A1IE);
@@ -602,6 +597,8 @@ static const struct rtc_class_ops ds13xx_rtc_ops = {
  * Alarm support for mcp794xx devices.
  */
 
+#define MCP794XX_REG_WEEKDAY		0x3
+#define MCP794XX_REG_WEEKDAY_WDAY_MASK	0x7
 #define MCP794XX_REG_CONTROL		0x07
 #	define MCP794XX_BIT_ALM0_EN	0x10
 #	define MCP794XX_BIT_ALM1_EN	0x20
@@ -1231,13 +1228,16 @@ static int ds1307_probe(struct i2c_client *client,
 {
 	struct ds1307		*ds1307;
 	int			err = -ENODEV;
-	int			tmp;
+	int			tmp, wday;
 	struct chip_desc	*chip = &chips[id->driver_data];
 	struct i2c_adapter	*adapter = to_i2c_adapter(client->dev.parent);
 	bool			want_irq = false;
 	bool			ds1307_can_wakeup_device = false;
 	unsigned char		*buf;
 	struct ds1307_platform_data *pdata = dev_get_platdata(&client->dev);
+	struct rtc_time		tm;
+	unsigned long		timestamp;
+
 	irq_handler_t	irq_handler = ds1307_irq;
 
 	static const int	bbsqi_bitpos[] = {
@@ -1526,6 +1526,27 @@ read_rtc:
 				bin2bcd(tmp));
 	}
 
+	/*
+	 * Some IPs have weekday reset value = 0x1 which might not correct
+	 * hence compute the wday using the current date/month/year values
+	 */
+	ds1307_get_time(&client->dev, &tm);
+	wday = tm.tm_wday;
+	timestamp = rtc_tm_to_time64(&tm);
+	rtc_time64_to_tm(timestamp, &tm);
+
+	/*
+	 * Check if reset wday is different from the computed wday
+	 * If different then set the wday which we computed using
+	 * timestamp
+	 */
+	if (wday != tm.tm_wday) {
+		wday = i2c_smbus_read_byte_data(client, MCP794XX_REG_WEEKDAY);
+		wday = wday & ~MCP794XX_REG_WEEKDAY_WDAY_MASK;
+		wday = wday | (tm.tm_wday + 1);
+		i2c_smbus_write_byte_data(client, MCP794XX_REG_WEEKDAY, wday);
+	}
+
 	if (want_irq) {
 		device_set_wakeup_capable(&client->dev, true);
 		set_bit(HAS_ALARM, &ds1307->flags);