Merge tag 'regmap-3.4' into regmap-stride

regmap: Last minute bug fix for 3.4

This is a last minute bug fix that was only just noticed since the code
path that's being exercised here is one that is fairly rarely used.  The
changelog for the change itself is extremely clear and the code itself
is obvious to inspection so should be pretty safe.

Conflicts:
	drivers/base/regmap/regmap.c (overlap between the fix and stride code)

1 files changed, 38 insertions, 5 deletions

diff --git a/drivers/rtc/rtc-twl.c b/drivers/rtc/rtc-twl.c
index 4c2c6df2a9e..258abeabf62 100644
--- a/drivers/rtc/rtc-twl.c
+++ b/drivers/rtc/rtc-twl.c
@@ -112,6 +112,7 @@ static const u8 twl6030_rtc_reg_map[] = {
 #define BIT_RTC_CTRL_REG_TEST_MODE_M             0x10
 #define BIT_RTC_CTRL_REG_SET_32_COUNTER_M        0x20
 #define BIT_RTC_CTRL_REG_GET_TIME_M              0x40
+#define BIT_RTC_CTRL_REG_RTC_V_OPT               0x80
 
 /* RTC_STATUS_REG bitfields */
 #define BIT_RTC_STATUS_REG_RUN_M                 0x02
@@ -235,25 +236,57 @@ static int twl_rtc_read_time(struct device *dev, struct rtc_time *tm)
 	unsigned char rtc_data[ALL_TIME_REGS + 1];
 	int ret;
 	u8 save_control;
+	u8 rtc_control;
 
 	ret = twl_rtc_read_u8(&save_control, REG_RTC_CTRL_REG);
-	if (ret < 0)
+	if (ret < 0) {
+		dev_err(dev, "%s: reading CTRL_REG, error %d\n", __func__, ret);
 		return ret;
+	}
+	/* for twl6030/32 make sure BIT_RTC_CTRL_REG_GET_TIME_M is clear */
+	if (twl_class_is_6030()) {
+		if (save_control & BIT_RTC_CTRL_REG_GET_TIME_M) {
+			save_control &= ~BIT_RTC_CTRL_REG_GET_TIME_M;
+			ret = twl_rtc_write_u8(save_control, REG_RTC_CTRL_REG);
+			if (ret < 0) {
+				dev_err(dev, "%s clr GET_TIME, error %d\n",
+					__func__, ret);
+				return ret;
+			}
+		}
+	}
 
-	save_control |= BIT_RTC_CTRL_REG_GET_TIME_M;
+	/* Copy RTC counting registers to static registers or latches */
+	rtc_control = save_control | BIT_RTC_CTRL_REG_GET_TIME_M;
 
-	ret = twl_rtc_write_u8(save_control, REG_RTC_CTRL_REG);
-	if (ret < 0)
+	/* for twl6030/32 enable read access to static shadowed registers */
+	if (twl_class_is_6030())
+		rtc_control |= BIT_RTC_CTRL_REG_RTC_V_OPT;
+
+	ret = twl_rtc_write_u8(rtc_control, REG_RTC_CTRL_REG);
+	if (ret < 0) {
+		dev_err(dev, "%s: writing CTRL_REG, error %d\n", __func__, ret);
 		return ret;
+	}
 
 	ret = twl_i2c_read(TWL_MODULE_RTC, rtc_data,
 			(rtc_reg_map[REG_SECONDS_REG]), ALL_TIME_REGS);
 
 	if (ret < 0) {
-		dev_err(dev, "rtc_read_time error %d\n", ret);
+		dev_err(dev, "%s: reading data, error %d\n", __func__, ret);
 		return ret;
 	}
 
+	/* for twl6030 restore original state of rtc control register */
+	if (twl_class_is_6030()) {
+		ret = twl_rtc_write_u8(save_control, REG_RTC_CTRL_REG);
+		if (ret < 0) {
+			dev_err(dev, "%s: restore CTRL_REG, error %d\n",
+				__func__, ret);
+			return ret;
+		}
+	}
+
 	tm->tm_sec = bcd2bin(rtc_data[0]);
 	tm->tm_min = bcd2bin(rtc_data[1]);
 	tm->tm_hour = bcd2bin(rtc_data[2]);