rtc: s5m: remove undocumented time init on first boot

Remove the code for initializing time if this is first boot.

The code for detecting first boot uses undocumented field RTC_TCON in
RTC_UDR_CON register.  According to S5M8767's datasheet this field is
reserved.  On S2MPS14 it is not documented at all.

On device first boot the registers will be initialized with reset value
(2000-01-01 00:00:00).

The code might work on S5M8763 but still this does not look like a task
for RTC driver.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Sangbeom Kim <sbkim73@samsung.com>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-s5m.c

@@ -517,16 +517,7 @@ static void s5m_rtc_enable_smpl(struct s5m_rtc_info *info, bool enable)
 static int s5m8767_rtc_init_reg(struct s5m_rtc_info *info)
 {
 	u8 data[2];
-	unsigned int tp_read;
 	int ret;
-	struct rtc_time tm;
-
-	ret = regmap_read(info->regmap, S5M_RTC_UDR_CON, &tp_read);
-	if (ret < 0) {
-		dev_err(info->dev, "%s: fail to read control reg(%d)\n",
-			__func__, ret);
-		return ret;
-	}
 
 	/* Set RTC control register : Binary mode, 24hour mode */
 	data[0] = (1 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
@@ -540,27 +531,6 @@ static int s5m8767_rtc_init_reg(struct s5m_rtc_info *info)
 		return ret;
 	}
 
-	/* In first boot time, Set rtc time to 1/1/2012 00:00:00(SUN) */
-	if ((tp_read & RTC_TCON_MASK) == 0) {
-		dev_dbg(info->dev, "rtc init\n");
-		tm.tm_sec = 0;
-		tm.tm_min = 0;
-		tm.tm_hour = 0;
-		tm.tm_wday = 0;
-		tm.tm_mday = 1;
-		tm.tm_mon = 0;
-		tm.tm_year = 112;
-		tm.tm_yday = 0;
-		tm.tm_isdst = 0;
-		ret = s5m_rtc_set_time(info->dev, &tm);
-	}
-
-	ret = regmap_update_bits(info->regmap, S5M_RTC_UDR_CON,
-				 RTC_TCON_MASK, tp_read | RTC_TCON_MASK);
-	if (ret < 0)
-		dev_err(info->dev, "%s: fail to update TCON reg(%d)\n",
-			__func__, ret);
-
 	return ret;
 }