rtc: s5m: add support for S2MPS14 RTC

Add support for S2MPS14 to the rtc-s5m driver.  Differences in S2MPS14
(in comparison to S5M8767):

 - Layout of registers
 - Lack of century support for time and alarms (7 registers used for
   storing time/alarm)
 - Two buffer control registers: WUDR and RUDR
 - No register for enabling writing time
 - RTC interrupts are reported in main PMIC I2C device

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>
diff --git a/drivers/rtc/rtc-s5m.c b/drivers/rtc/rtc-s5m.c
index 5986012..76287eb 100644
--- a/drivers/rtc/rtc-s5m.c
+++ b/drivers/rtc/rtc-s5m.c
@@ -17,16 +17,14 @@
 
 #include <linux/module.h>
 #include <linux/i2c.h>
-#include <linux/slab.h>
 #include <linux/bcd.h>
-#include <linux/bitops.h>
 #include <linux/regmap.h>
 #include <linux/rtc.h>
-#include <linux/delay.h>
 #include <linux/platform_device.h>
 #include <linux/mfd/samsung/core.h>
 #include <linux/mfd/samsung/irq.h>
 #include <linux/mfd/samsung/rtc.h>
+#include <linux/mfd/samsung/s2mps14.h>
 
 /*
  * Maximum number of retries for checking changes in UDR field
@@ -74,6 +72,21 @@
 	.rtc_udr_mask		= S5M_RTC_UDR_MASK,
 };
 
+/*
+ * Register map for S2MPS14.
+ * It may be also suitable for S2MPS11 but this was not tested.
+ */
+static const struct s5m_rtc_reg_config s2mps_rtc_regs = {
+	.regs_count		= 7,
+	.time			= S2MPS_RTC_SEC,
+	.ctrl			= S2MPS_RTC_CTRL,
+	.alarm0			= S2MPS_ALARM0_SEC,
+	.alarm1			= S2MPS_ALARM1_SEC,
+	.smpl_wtsr		= S2MPS_WTSR_SMPL_CNTL,
+	.rtc_udr_update		= S2MPS_RTC_UDR_CON,
+	.rtc_udr_mask		= S2MPS_RTC_WUDR_MASK,
+};
+
 struct s5m_rtc_info {
 	struct device *dev;
 	struct i2c_client *i2c;
@@ -178,6 +191,11 @@
 		ret = regmap_read(info->regmap, S5M_RTC_STATUS, &val);
 		val &= S5M_ALARM0_STATUS;
 		break;
+	case S2MPS14X:
+		ret = regmap_read(info->s5m87xx->regmap_pmic, S2MPS14_REG_ST2,
+				&val);
+		val &= S2MPS_ALARM0_STATUS;
+		break;
 	default:
 		return -EINVAL;
 	}
@@ -203,8 +221,9 @@
 		return ret;
 	}
 
-	data |= S5M_RTC_TIME_EN_MASK;
 	data |= info->regs->rtc_udr_mask;
+	if (info->device_type == S5M8763X || info->device_type == S5M8767X)
+		data |= S5M_RTC_TIME_EN_MASK;
 
 	ret = regmap_write(info->regmap, info->regs->rtc_udr_update, data);
 	if (ret < 0) {
@@ -229,8 +248,18 @@
 		return ret;
 	}
 
-	data &= ~S5M_RTC_TIME_EN_MASK;
 	data |= info->regs->rtc_udr_mask;
+	switch (info->device_type) {
+	case S5M8763X:
+	case S5M8767X:
+		data &= ~S5M_RTC_TIME_EN_MASK;
+		break;
+	case S2MPS14X:
+		data |= S2MPS_RTC_RUDR_MASK;
+		break;
+	default:
+		return -EINVAL;
+	}
 
 	ret = regmap_write(info->regmap, info->regs->rtc_udr_update, data);
 	if (ret < 0) {
@@ -282,6 +311,17 @@
 	u8 data[info->regs->regs_count];
 	int ret;
 
+	if (info->device_type == S2MPS14X) {
+		ret = regmap_update_bits(info->regmap,
+				info->regs->rtc_udr_update,
+				S2MPS_RTC_RUDR_MASK, S2MPS_RTC_RUDR_MASK);
+		if (ret) {
+			dev_err(dev,
+				"Failed to prepare registers for time reading: %d\n",
+				ret);
+			return ret;
+		}
+	}
 	ret = regmap_bulk_read(info->regmap, info->regs->time, data,
 			info->regs->regs_count);
 	if (ret < 0)
@@ -293,6 +333,7 @@
 		break;
 
 	case S5M8767X:
+	case S2MPS14X:
 		s5m8767_data_to_tm(data, tm, info->rtc_24hr_mode);
 		break;
 
@@ -318,6 +359,7 @@
 		s5m8763_tm_to_data(tm, data);
 		break;
 	case S5M8767X:
+	case S2MPS14X:
 		ret = s5m8767_tm_to_data(tm, data);
 		break;
 	default:
@@ -364,6 +406,7 @@
 		break;
 
 	case S5M8767X:
+	case S2MPS14X:
 		s5m8767_data_to_tm(data, &alrm->time, info->rtc_24hr_mode);
 		alrm->enabled = 0;
 		for (i = 0; i < info->regs->regs_count; i++) {
@@ -411,6 +454,7 @@
 		break;
 
 	case S5M8767X:
+	case S2MPS14X:
 		for (i = 0; i < info->regs->regs_count; i++)
 			data[i] &= ~ALARM_ENABLE_MASK;
 
@@ -454,6 +498,7 @@
 		break;
 
 	case S5M8767X:
+	case S2MPS14X:
 		data[RTC_SEC] |= ALARM_ENABLE_MASK;
 		data[RTC_MIN] |= ALARM_ENABLE_MASK;
 		data[RTC_HOUR] |= ALARM_ENABLE_MASK;
@@ -492,6 +537,7 @@
 		break;
 
 	case S5M8767X:
+	case S2MPS14X:
 		s5m8767_tm_to_data(&alrm->time, data);
 		break;
 
@@ -578,19 +624,33 @@
 	u8 data[2];
 	int ret;
 
-	/* UDR update time. Default of 7.32 ms is too long. */
-	ret = regmap_update_bits(info->regmap, S5M_RTC_UDR_CON,
-			S5M_RTC_UDR_T_MASK, S5M_RTC_UDR_T_450_US);
-	if (ret < 0)
-		dev_err(info->dev, "%s: fail to change UDR time: %d\n",
-				__func__, ret);
+	switch (info->device_type) {
+	case S5M8763X:
+	case S5M8767X:
+		/* UDR update time. Default of 7.32 ms is too long. */
+		ret = regmap_update_bits(info->regmap, S5M_RTC_UDR_CON,
+				S5M_RTC_UDR_T_MASK, S5M_RTC_UDR_T_450_US);
+		if (ret < 0)
+			dev_err(info->dev, "%s: fail to change UDR time: %d\n",
+					__func__, ret);
 
-	/* Set RTC control register : Binary mode, 24hour mode */
-	data[0] = (1 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
-	data[1] = (0 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
+		/* Set RTC control register : Binary mode, 24hour mode */
+		data[0] = (1 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
+		data[1] = (0 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
+
+		ret = regmap_raw_write(info->regmap, S5M_ALARM0_CONF, data, 2);
+		break;
+
+	case S2MPS14X:
+		data[0] = (0 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT);
+		ret = regmap_write(info->regmap, info->regs->ctrl, data[0]);
+		break;
+
+	default:
+		return -EINVAL;
+	}
 
 	info->rtc_24hr_mode = 1;
-	ret = regmap_raw_write(info->regmap, S5M_ALARM0_CONF, data, 2);
 	if (ret < 0) {
 		dev_err(info->dev, "%s: fail to write controlm reg(%d)\n",
 			__func__, ret);
@@ -620,6 +680,7 @@
 	switch (pdata->device_type) {
 	case S2MPS14X:
 		regmap_cfg = &s2mps14_rtc_regmap_config;
+		info->regs = &s2mps_rtc_regs;
 		break;
 	case S5M8763X:
 		regmap_cfg = &s5m_rtc_regmap_config;
@@ -654,6 +715,11 @@
 	info->wtsr_smpl = s5m87xx->wtsr_smpl;
 
 	switch (pdata->device_type) {
+	case S2MPS14X:
+		info->irq = regmap_irq_get_virq(s5m87xx->irq_data,
+				S2MPS14_IRQ_RTCA0);
+		break;
+
 	case S5M8763X:
 		info->irq = regmap_irq_get_virq(s5m87xx->irq_data,
 				S5M8763_IRQ_ALARM0);
@@ -768,7 +834,8 @@
 static SIMPLE_DEV_PM_OPS(s5m_rtc_pm_ops, s5m_rtc_suspend, s5m_rtc_resume);
 
 static const struct platform_device_id s5m_rtc_id[] = {
-	{ "s5m-rtc", 0 },
+	{ "s5m-rtc",		S5M8767X },
+	{ "s2mps14-rtc",	S2MPS14X },
 };
 
 static struct platform_driver s5m_rtc_driver = {
@@ -787,6 +854,6 @@
 
 /* Module information */
 MODULE_AUTHOR("Sangbeom Kim <sbkim73@samsung.com>");
-MODULE_DESCRIPTION("Samsung S5M RTC driver");
+MODULE_DESCRIPTION("Samsung S5M/S2MPS14 RTC driver");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS("platform:s5m-rtc");