[v3,06/10] rtc: max77686: Add max77802 support
diff mbox

Message ID 1453836020-29579-7-git-send-email-javier@osg.samsung.com
State New, archived
Headers show

Commit Message

Javier Martinez Canillas Jan. 26, 2016, 7:20 p.m. UTC
The MAX77686 and MAX77802 RTC IP blocks are very similar with only
these differences:

0) The RTC registers layout and addresses are different.

1) The MAX77686 use 1 bit of the sec/min/hour/etc registers as the
   alarm enable while MAX77802 has a separate register for that.

2) The MAX77686 RTCYEAR register valid values range is 0..99 while
   for MAX77802 is 0..199.

3) The MAX77686 has a separate I2C address for the RTC registers
   while the MAX77802 uses the same I2C address as the PMIC regs.

5) The minimum delay before a RTC update (16 msecs vs 200 usecs).

There are separate drivers for MAX77686 and MAX77802 RTC IP blocks
but the differences are not that big so the driver can be extended
to support both instead of duplicating a lot of code in 2 drivers.

Suggested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>

---

Changes in v3:
- Add Laxman Dewangan's Acked-by tag to patch #6.

Changes in v2:
- Add a MAX77802 prefix to ALARM_ENABLE_VALUE. Suggested by Krzysztof Kozlowski.
- Rename .rtcae to .alarm_enable_reg and .rtcrm to .separate_i2c_addr.
  Suggested by Krzysztof Kozlowski.
- Don't use func and LINE in error messages. Suggested by Krzysztof Kozlowski.
- Remove REG_RTC_AE2 since is not used by neither max77686 nor max77802.
- Check if REG_RTC_AE1 has a valid address before accessing it.

 drivers/rtc/rtc-max77686.c | 208 +++++++++++++++++++++++++++++++++++----------
 1 file changed, 162 insertions(+), 46 deletions(-)

Comments

Krzysztof Kozlowski Jan. 27, 2016, 1:59 a.m. UTC | #1
On 27.01.2016 04:20, Javier Martinez Canillas wrote:
> The MAX77686 and MAX77802 RTC IP blocks are very similar with only
> these differences:
> 
> 0) The RTC registers layout and addresses are different.
> 
> 1) The MAX77686 use 1 bit of the sec/min/hour/etc registers as the
>    alarm enable while MAX77802 has a separate register for that.
> 
> 2) The MAX77686 RTCYEAR register valid values range is 0..99 while
>    for MAX77802 is 0..199.
> 
> 3) The MAX77686 has a separate I2C address for the RTC registers
>    while the MAX77802 uses the same I2C address as the PMIC regs.
> 
> 5) The minimum delay before a RTC update (16 msecs vs 200 usecs).
> 
> There are separate drivers for MAX77686 and MAX77802 RTC IP blocks
> but the differences are not that big so the driver can be extended
> to support both instead of duplicating a lot of code in 2 drivers.
> 
> Suggested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
> Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
> Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
> 
> ---
> 
> Changes in v3:
> - Add Laxman Dewangan's Acked-by tag to patch #6.
> 
> Changes in v2:
> - Add a MAX77802 prefix to ALARM_ENABLE_VALUE. Suggested by Krzysztof Kozlowski.
> - Rename .rtcae to .alarm_enable_reg and .rtcrm to .separate_i2c_addr.
>   Suggested by Krzysztof Kozlowski.
> - Don't use func and LINE in error messages. Suggested by Krzysztof Kozlowski.
> - Remove REG_RTC_AE2 since is not used by neither max77686 nor max77802.
> - Check if REG_RTC_AE1 has a valid address before accessing it.
> 
>  drivers/rtc/rtc-max77686.c | 208 +++++++++++++++++++++++++++++++++++----------
>  1 file changed, 162 insertions(+), 46 deletions(-)
> 
> diff --git a/drivers/rtc/rtc-max77686.c b/drivers/rtc/rtc-max77686.c
> index 1f501b6fc314..09fc73016d3a 100644
> --- a/drivers/rtc/rtc-max77686.c
> +++ b/drivers/rtc/rtc-max77686.c
> @@ -1,5 +1,5 @@
>  /*
> - * RTC driver for Maxim MAX77686
> + * RTC driver for Maxim MAX77686 and MAX77802
>   *
>   * Copyright (C) 2012 Samsung Electronics Co.Ltd
>   *
> @@ -41,6 +41,15 @@
>  #define ALARM_ENABLE_SHIFT		7
>  #define ALARM_ENABLE_MASK		(1 << ALARM_ENABLE_SHIFT)
>  
> +#define REG_RTC_NONE			0xdeadbeef
> +
> +/*
> + * MAX77802 has separate register (RTCAE1) for alarm enable instead
> + * using 1 bit from registers RTC{SEC,MIN,HOUR,DAY,MONTH,YEAR,DATE}
> + * as in done in MAX77686.
> + */
> +#define MAX77802_ALARM_ENABLE_VALUE	0x77
> +
>  enum {
>  	RTC_SEC = 0,
>  	RTC_MIN,
> @@ -59,6 +68,10 @@ struct max77686_rtc_driver_data {
>  	u8			mask;
>  	/* Registers offset to I2C addresses map */
>  	const unsigned int	*map;
> +	/* Has a separate alarm enable register? */
> +	bool			alarm_enable_reg;
> +	/* Has a separate I2C regmap for the RTC? */
> +	bool			separate_i2c_addr;
>  };
>  
>  struct max77686_rtc_info {
> @@ -108,6 +121,7 @@ enum max77686_rtc_reg_offset {
>  	REG_ALARM2_MONTH,
>  	REG_ALARM2_YEAR,
>  	REG_ALARM2_DATE,
> +	REG_RTC_AE1,
>  	REG_RTC_END,
>  };
>  
> @@ -138,12 +152,52 @@ static const unsigned int max77686_map[REG_RTC_END] = {
>  	[REG_ALARM2_MONTH]   = MAX77686_ALARM2_MONTH,
>  	[REG_ALARM2_YEAR]    = MAX77686_ALARM2_YEAR,
>  	[REG_ALARM2_DATE]    = MAX77686_ALARM2_DATE,
> +	[REG_RTC_AE1]	     = REG_RTC_NONE,
>  };
>  
>  static const struct max77686_rtc_driver_data max77686_drv_data = {
>  	.delay = 16000,
>  	.mask  = 0x7f,
>  	.map   = max77686_map,
> +	.alarm_enable_reg  = false,
> +	.separate_i2c_addr = true,
> +};
> +
> +static const unsigned int max77802_map[REG_RTC_END] = {
> +	[REG_RTC_CONTROLM]   = MAX77802_RTC_CONTROLM,
> +	[REG_RTC_CONTROL]    = MAX77802_RTC_CONTROL,
> +	[REG_RTC_UPDATE0]    = MAX77802_RTC_UPDATE0,
> +	[REG_WTSR_SMPL_CNTL] = MAX77802_WTSR_SMPL_CNTL,
> +	[REG_RTC_SEC]        = MAX77802_RTC_SEC,
> +	[REG_RTC_MIN]        = MAX77802_RTC_MIN,
> +	[REG_RTC_HOUR]       = MAX77802_RTC_HOUR,
> +	[REG_RTC_WEEKDAY]    = MAX77802_RTC_WEEKDAY,
> +	[REG_RTC_MONTH]      = MAX77802_RTC_MONTH,
> +	[REG_RTC_YEAR]       = MAX77802_RTC_YEAR,
> +	[REG_RTC_DATE]       = MAX77802_RTC_DATE,
> +	[REG_ALARM1_SEC]     = MAX77802_ALARM1_SEC,
> +	[REG_ALARM1_MIN]     = MAX77802_ALARM1_MIN,
> +	[REG_ALARM1_HOUR]    = MAX77802_ALARM1_HOUR,
> +	[REG_ALARM1_WEEKDAY] = MAX77802_ALARM1_WEEKDAY,
> +	[REG_ALARM1_MONTH]   = MAX77802_ALARM1_MONTH,
> +	[REG_ALARM1_YEAR]    = MAX77802_ALARM1_YEAR,
> +	[REG_ALARM1_DATE]    = MAX77802_ALARM1_DATE,
> +	[REG_ALARM2_SEC]     = MAX77802_ALARM2_SEC,
> +	[REG_ALARM2_MIN]     = MAX77802_ALARM2_MIN,
> +	[REG_ALARM2_HOUR]    = MAX77802_ALARM2_HOUR,
> +	[REG_ALARM2_WEEKDAY] = MAX77802_ALARM2_WEEKDAY,
> +	[REG_ALARM2_MONTH]   = MAX77802_ALARM2_MONTH,
> +	[REG_ALARM2_YEAR]    = MAX77802_ALARM2_YEAR,
> +	[REG_ALARM2_DATE]    = MAX77802_ALARM2_DATE,
> +	[REG_RTC_AE1]	     = MAX77802_RTC_AE1,
> +};
> +
> +static const struct max77686_rtc_driver_data max77802_drv_data = {
> +	.delay = 200,
> +	.mask  = 0xff,
> +	.map   = max77802_map,
> +	.alarm_enable_reg  = true,
> +	.separate_i2c_addr = false,
>  };
>  
>  static void max77686_rtc_data_to_tm(u8 *data, struct rtc_time *tm,
> @@ -165,12 +219,20 @@ static void max77686_rtc_data_to_tm(u8 *data, struct rtc_time *tm,
>  	tm->tm_wday = ffs(data[RTC_WEEKDAY] & mask) - 1;
>  	tm->tm_mday = data[RTC_DATE] & 0x1f;
>  	tm->tm_mon = (data[RTC_MONTH] & 0x0f) - 1;
> -	tm->tm_year = (data[RTC_YEAR] & mask) + 100;
> +	tm->tm_year = data[RTC_YEAR] & mask;
>  	tm->tm_yday = 0;
>  	tm->tm_isdst = 0;
> +
> +	/*
> +	 * MAX77686 uses 1 bit from sec/min/hour/etc RTC registers and the
> +	 * year values are just 0..99 so add 100 to support up to 2099.
> +	 */
> +	if (!info->drv_data->alarm_enable_reg)
> +		tm->tm_year += 100;
>  }
>  
> -static int max77686_rtc_tm_to_data(struct rtc_time *tm, u8 *data)
> +static int max77686_rtc_tm_to_data(struct rtc_time *tm, u8 *data,
> +				   struct max77686_rtc_info *info)
>  {
>  	data[RTC_SEC] = tm->tm_sec;
>  	data[RTC_MIN] = tm->tm_min;
> @@ -178,13 +240,19 @@ static int max77686_rtc_tm_to_data(struct rtc_time *tm, u8 *data)
>  	data[RTC_WEEKDAY] = 1 << tm->tm_wday;
>  	data[RTC_DATE] = tm->tm_mday;
>  	data[RTC_MONTH] = tm->tm_mon + 1;
> -	data[RTC_YEAR] = tm->tm_year > 100 ? (tm->tm_year - 100) : 0;
>  
> -	if (tm->tm_year < 100) {
> -		pr_warn("RTC cannot handle the year %d.  Assume it's 2000.\n",
> -			1900 + tm->tm_year);
> -		return -EINVAL;
> +	if (!info->drv_data->alarm_enable_reg) {

I don't like all these inverted checks. They are error-prone. This is
why I propose different name. However since you want to stick to this
name of this property, then easier to read would be:

if (info->drv_data->alarm_enable_reg) {
	data[RTC_YEAR] = tm->tm_year;
} else {
	max77686-stuff...
}
Can you reverse it here and in other places?

The patch beside that is okay and works fine:

Tested on Trats2 (max77686):
Tested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>

BR,
Krzysztof

> +		data[RTC_YEAR] = tm->tm_year > 100 ? (tm->tm_year - 100) : 0;
> +
> +		if (tm->tm_year < 100) {
> +			pr_warn("RTC can't handle year %d. Assume it's 2000.\n",
> +				1900 + tm->tm_year);
> +			return -EINVAL;
> +		}
> +	} else {
> +		data[RTC_YEAR] = tm->tm_year;
>  	}
> +
>  	return 0;
>  }
>
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Andi Shyti Jan. 27, 2016, 2:22 a.m. UTC | #2
On Tue, Jan 26, 2016 at 04:20:16PM -0300, Javier Martinez Canillas wrote:
> The MAX77686 and MAX77802 RTC IP blocks are very similar with only
> these differences:
> 
> 0) The RTC registers layout and addresses are different.
> 
> 1) The MAX77686 use 1 bit of the sec/min/hour/etc registers as the
>    alarm enable while MAX77802 has a separate register for that.
> 
> 2) The MAX77686 RTCYEAR register valid values range is 0..99 while
>    for MAX77802 is 0..199.
> 
> 3) The MAX77686 has a separate I2C address for the RTC registers
>    while the MAX77802 uses the same I2C address as the PMIC regs.
> 
> 5) The minimum delay before a RTC update (16 msecs vs 200 usecs).
> 
> There are separate drivers for MAX77686 and MAX77802 RTC IP blocks
> but the differences are not that big so the driver can be extended
> to support both instead of duplicating a lot of code in 2 drivers.
> 
> Suggested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
> Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
> Acked-by: Laxman Dewangan <ldewangan@nvidia.com>

Reviewed-by: Andi Shyti <andi.shyti@samsung.com>

Just a nitpick, though.

> -static int max77686_rtc_tm_to_data(struct rtc_time *tm, u8 *data)
> +static int max77686_rtc_tm_to_data(struct rtc_time *tm, u8 *data,
> +				   struct max77686_rtc_info *info)
>  {
>  	data[RTC_SEC] = tm->tm_sec;
>  	data[RTC_MIN] = tm->tm_min;
> @@ -178,13 +240,19 @@ static int max77686_rtc_tm_to_data(struct rtc_time *tm, u8 *data)
>  	data[RTC_WEEKDAY] = 1 << tm->tm_wday;
>  	data[RTC_DATE] = tm->tm_mday;
>  	data[RTC_MONTH] = tm->tm_mon + 1;
> -	data[RTC_YEAR] = tm->tm_year > 100 ? (tm->tm_year - 100) : 0;
>  
> -	if (tm->tm_year < 100) {
> -		pr_warn("RTC cannot handle the year %d.  Assume it's 2000.\n",
> -			1900 + tm->tm_year);
> -		return -EINVAL;
> +	if (!info->drv_data->alarm_enable_reg) {
> +		data[RTC_YEAR] = tm->tm_year > 100 ? (tm->tm_year - 100) : 0;
> +
> +		if (tm->tm_year < 100) {
> +			pr_warn("RTC can't handle year %d. Assume it's 2000.\n",
> +				1900 + tm->tm_year);
> +			return -EINVAL;
> +		}
> +	} else {
> +		data[RTC_YEAR] = tm->tm_year;
>  	}
> +

This can be written als as:

if (info->drv_data->alarm_enable_reg) {
	data[RTC_YEAR] = tm->tm_year;
	return 0;
}

[ ... the rest without any indentation ...]

We make also Krzysztof happy by avoiding the if (!...)

>  	return 0;
>  }
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Javier Martinez Canillas Jan. 27, 2016, 2:24 a.m. UTC | #3
Hello Krzysztof,

On Tue, Jan 26, 2016 at 10:59 PM, Krzysztof Kozlowski
<k.kozlowski@samsung.com> wrote:
> On 27.01.2016 04:20, Javier Martinez Canillas wrote:

[snip]

>>       data[RTC_MONTH] = tm->tm_mon + 1;
>> -     data[RTC_YEAR] = tm->tm_year > 100 ? (tm->tm_year - 100) : 0;
>>
>> -     if (tm->tm_year < 100) {
>> -             pr_warn("RTC cannot handle the year %d.  Assume it's 2000.\n",
>> -                     1900 + tm->tm_year);
>> -             return -EINVAL;
>> +     if (!info->drv_data->alarm_enable_reg) {
>
> I don't like all these inverted checks. They are error-prone. This is
> why I propose different name. However since you want to stick to this
> name of this property, then easier to read would be:
>
> if (info->drv_data->alarm_enable_reg) {
>         data[RTC_YEAR] = tm->tm_year;
> } else {
>         max77686-stuff...
> }
> Can you reverse it here and in other places?
>

Fair enough, I'll reverse the logic so is more natural and also do an
early return as Andi suggested.

> The patch beside that is okay and works fine:
>
> Tested on Trats2 (max77686):
> Tested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
>
> BR,
> Krzysztof
>

Best regards,
Javier
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Patch
diff mbox

diff --git a/drivers/rtc/rtc-max77686.c b/drivers/rtc/rtc-max77686.c
index 1f501b6fc314..09fc73016d3a 100644
--- a/drivers/rtc/rtc-max77686.c
+++ b/drivers/rtc/rtc-max77686.c
@@ -1,5 +1,5 @@ 
 /*
- * RTC driver for Maxim MAX77686
+ * RTC driver for Maxim MAX77686 and MAX77802
  *
  * Copyright (C) 2012 Samsung Electronics Co.Ltd
  *
@@ -41,6 +41,15 @@ 
 #define ALARM_ENABLE_SHIFT		7
 #define ALARM_ENABLE_MASK		(1 << ALARM_ENABLE_SHIFT)
 
+#define REG_RTC_NONE			0xdeadbeef
+
+/*
+ * MAX77802 has separate register (RTCAE1) for alarm enable instead
+ * using 1 bit from registers RTC{SEC,MIN,HOUR,DAY,MONTH,YEAR,DATE}
+ * as in done in MAX77686.
+ */
+#define MAX77802_ALARM_ENABLE_VALUE	0x77
+
 enum {
 	RTC_SEC = 0,
 	RTC_MIN,
@@ -59,6 +68,10 @@  struct max77686_rtc_driver_data {
 	u8			mask;
 	/* Registers offset to I2C addresses map */
 	const unsigned int	*map;
+	/* Has a separate alarm enable register? */
+	bool			alarm_enable_reg;
+	/* Has a separate I2C regmap for the RTC? */
+	bool			separate_i2c_addr;
 };
 
 struct max77686_rtc_info {
@@ -108,6 +121,7 @@  enum max77686_rtc_reg_offset {
 	REG_ALARM2_MONTH,
 	REG_ALARM2_YEAR,
 	REG_ALARM2_DATE,
+	REG_RTC_AE1,
 	REG_RTC_END,
 };
 
@@ -138,12 +152,52 @@  static const unsigned int max77686_map[REG_RTC_END] = {
 	[REG_ALARM2_MONTH]   = MAX77686_ALARM2_MONTH,
 	[REG_ALARM2_YEAR]    = MAX77686_ALARM2_YEAR,
 	[REG_ALARM2_DATE]    = MAX77686_ALARM2_DATE,
+	[REG_RTC_AE1]	     = REG_RTC_NONE,
 };
 
 static const struct max77686_rtc_driver_data max77686_drv_data = {
 	.delay = 16000,
 	.mask  = 0x7f,
 	.map   = max77686_map,
+	.alarm_enable_reg  = false,
+	.separate_i2c_addr = true,
+};
+
+static const unsigned int max77802_map[REG_RTC_END] = {
+	[REG_RTC_CONTROLM]   = MAX77802_RTC_CONTROLM,
+	[REG_RTC_CONTROL]    = MAX77802_RTC_CONTROL,
+	[REG_RTC_UPDATE0]    = MAX77802_RTC_UPDATE0,
+	[REG_WTSR_SMPL_CNTL] = MAX77802_WTSR_SMPL_CNTL,
+	[REG_RTC_SEC]        = MAX77802_RTC_SEC,
+	[REG_RTC_MIN]        = MAX77802_RTC_MIN,
+	[REG_RTC_HOUR]       = MAX77802_RTC_HOUR,
+	[REG_RTC_WEEKDAY]    = MAX77802_RTC_WEEKDAY,
+	[REG_RTC_MONTH]      = MAX77802_RTC_MONTH,
+	[REG_RTC_YEAR]       = MAX77802_RTC_YEAR,
+	[REG_RTC_DATE]       = MAX77802_RTC_DATE,
+	[REG_ALARM1_SEC]     = MAX77802_ALARM1_SEC,
+	[REG_ALARM1_MIN]     = MAX77802_ALARM1_MIN,
+	[REG_ALARM1_HOUR]    = MAX77802_ALARM1_HOUR,
+	[REG_ALARM1_WEEKDAY] = MAX77802_ALARM1_WEEKDAY,
+	[REG_ALARM1_MONTH]   = MAX77802_ALARM1_MONTH,
+	[REG_ALARM1_YEAR]    = MAX77802_ALARM1_YEAR,
+	[REG_ALARM1_DATE]    = MAX77802_ALARM1_DATE,
+	[REG_ALARM2_SEC]     = MAX77802_ALARM2_SEC,
+	[REG_ALARM2_MIN]     = MAX77802_ALARM2_MIN,
+	[REG_ALARM2_HOUR]    = MAX77802_ALARM2_HOUR,
+	[REG_ALARM2_WEEKDAY] = MAX77802_ALARM2_WEEKDAY,
+	[REG_ALARM2_MONTH]   = MAX77802_ALARM2_MONTH,
+	[REG_ALARM2_YEAR]    = MAX77802_ALARM2_YEAR,
+	[REG_ALARM2_DATE]    = MAX77802_ALARM2_DATE,
+	[REG_RTC_AE1]	     = MAX77802_RTC_AE1,
+};
+
+static const struct max77686_rtc_driver_data max77802_drv_data = {
+	.delay = 200,
+	.mask  = 0xff,
+	.map   = max77802_map,
+	.alarm_enable_reg  = true,
+	.separate_i2c_addr = false,
 };
 
 static void max77686_rtc_data_to_tm(u8 *data, struct rtc_time *tm,
@@ -165,12 +219,20 @@  static void max77686_rtc_data_to_tm(u8 *data, struct rtc_time *tm,
 	tm->tm_wday = ffs(data[RTC_WEEKDAY] & mask) - 1;
 	tm->tm_mday = data[RTC_DATE] & 0x1f;
 	tm->tm_mon = (data[RTC_MONTH] & 0x0f) - 1;
-	tm->tm_year = (data[RTC_YEAR] & mask) + 100;
+	tm->tm_year = data[RTC_YEAR] & mask;
 	tm->tm_yday = 0;
 	tm->tm_isdst = 0;
+
+	/*
+	 * MAX77686 uses 1 bit from sec/min/hour/etc RTC registers and the
+	 * year values are just 0..99 so add 100 to support up to 2099.
+	 */
+	if (!info->drv_data->alarm_enable_reg)
+		tm->tm_year += 100;
 }
 
-static int max77686_rtc_tm_to_data(struct rtc_time *tm, u8 *data)
+static int max77686_rtc_tm_to_data(struct rtc_time *tm, u8 *data,
+				   struct max77686_rtc_info *info)
 {
 	data[RTC_SEC] = tm->tm_sec;
 	data[RTC_MIN] = tm->tm_min;
@@ -178,13 +240,19 @@  static int max77686_rtc_tm_to_data(struct rtc_time *tm, u8 *data)
 	data[RTC_WEEKDAY] = 1 << tm->tm_wday;
 	data[RTC_DATE] = tm->tm_mday;
 	data[RTC_MONTH] = tm->tm_mon + 1;
-	data[RTC_YEAR] = tm->tm_year > 100 ? (tm->tm_year - 100) : 0;
 
-	if (tm->tm_year < 100) {
-		pr_warn("RTC cannot handle the year %d.  Assume it's 2000.\n",
-			1900 + tm->tm_year);
-		return -EINVAL;
+	if (!info->drv_data->alarm_enable_reg) {
+		data[RTC_YEAR] = tm->tm_year > 100 ? (tm->tm_year - 100) : 0;
+
+		if (tm->tm_year < 100) {
+			pr_warn("RTC can't handle year %d. Assume it's 2000.\n",
+				1900 + tm->tm_year);
+			return -EINVAL;
+		}
+	} else {
+		data[RTC_YEAR] = tm->tm_year;
 	}
+
 	return 0;
 }
 
@@ -249,7 +317,7 @@  static int max77686_rtc_set_time(struct device *dev, struct rtc_time *tm)
 	u8 data[RTC_NR_TIME];
 	int ret;
 
-	ret = max77686_rtc_tm_to_data(tm, data);
+	ret = max77686_rtc_tm_to_data(tm, data, info);
 	if (ret < 0)
 		return ret;
 
@@ -296,11 +364,32 @@  static int max77686_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 	max77686_rtc_data_to_tm(data, &alrm->time, info);
 
 	alrm->enabled = 0;
-	for (i = 0; i < ARRAY_SIZE(data); i++) {
-		if (data[i] & ALARM_ENABLE_MASK) {
-			alrm->enabled = 1;
-			break;
+
+	if (!info->drv_data->alarm_enable_reg) {
+		for (i = 0; i < ARRAY_SIZE(data); i++) {
+			if (data[i] & ALARM_ENABLE_MASK) {
+				alrm->enabled = 1;
+				break;
+			}
+		}
+	} else {
+		if (map[REG_RTC_AE1] == REG_RTC_NONE) {
+			ret = -EINVAL;
+			dev_err(info->dev,
+				"alarm enable register not set(%d)\n", ret);
+			goto out;
 		}
+
+		ret = regmap_read(info->max77686->regmap,
+				  map[REG_RTC_AE1], &val);
+		if (ret < 0) {
+			dev_err(info->dev,
+				"fail to read alarm enable(%d)\n", ret);
+			goto out;
+		}
+
+		if (val)
+			alrm->enabled = 1;
 	}
 
 	alrm->pending = 0;
@@ -333,21 +422,36 @@  static int max77686_rtc_stop_alarm(struct max77686_rtc_info *info)
 	if (ret < 0)
 		goto out;
 
-	ret = regmap_bulk_read(info->max77686->rtc_regmap,
-			       map[REG_ALARM1_SEC], data, ARRAY_SIZE(data));
-	if (ret < 0) {
-		dev_err(info->dev, "%s: fail to read alarm reg(%d)\n",
+	if (!info->drv_data->alarm_enable_reg) {
+		ret = regmap_bulk_read(info->max77686->rtc_regmap,
+				       map[REG_ALARM1_SEC], data,
+				       ARRAY_SIZE(data));
+		if (ret < 0) {
+			dev_err(info->dev, "%s: fail to read alarm reg(%d)\n",
 				__func__, ret);
-		goto out;
-	}
+			goto out;
+		}
 
-	max77686_rtc_data_to_tm(data, &tm, info);
+		max77686_rtc_data_to_tm(data, &tm, info);
 
-	for (i = 0; i < ARRAY_SIZE(data); i++)
-		data[i] &= ~ALARM_ENABLE_MASK;
+		for (i = 0; i < ARRAY_SIZE(data); i++)
+			data[i] &= ~ALARM_ENABLE_MASK;
+
+		ret = regmap_bulk_write(info->max77686->rtc_regmap,
+					map[REG_ALARM1_SEC], data,
+					ARRAY_SIZE(data));
+	} else {
+		if (map[REG_RTC_AE1] == REG_RTC_NONE) {
+			ret = -EINVAL;
+			dev_err(info->dev,
+				"alarm enable register not set(%d)\n", ret);
+			goto out;
+		}
+
+		ret = regmap_write(info->max77686->regmap,
+				   map[REG_RTC_AE1], 0);
+	}
 
-	ret = regmap_bulk_write(info->max77686->rtc_regmap,
-				map[REG_ALARM1_SEC], data, ARRAY_SIZE(data));
 	if (ret < 0) {
 		dev_err(info->dev, "%s: fail to write alarm reg(%d)\n",
 				__func__, ret);
@@ -373,29 +477,37 @@  static int max77686_rtc_start_alarm(struct max77686_rtc_info *info)
 	if (ret < 0)
 		goto out;
 
-	ret = regmap_bulk_read(info->max77686->rtc_regmap,
-			       map[REG_ALARM1_SEC], data, ARRAY_SIZE(data));
-	if (ret < 0) {
-		dev_err(info->dev, "%s: fail to read alarm reg(%d)\n",
+	if (!info->drv_data->alarm_enable_reg) {
+		ret = regmap_bulk_read(info->max77686->rtc_regmap,
+				       map[REG_ALARM1_SEC], data,
+				       ARRAY_SIZE(data));
+		if (ret < 0) {
+			dev_err(info->dev, "%s: fail to read alarm reg(%d)\n",
 				__func__, ret);
-		goto out;
-	}
-
-	max77686_rtc_data_to_tm(data, &tm, info);
+			goto out;
+		}
 
-	data[RTC_SEC] |= (1 << ALARM_ENABLE_SHIFT);
-	data[RTC_MIN] |= (1 << ALARM_ENABLE_SHIFT);
-	data[RTC_HOUR] |= (1 << ALARM_ENABLE_SHIFT);
-	data[RTC_WEEKDAY] &= ~ALARM_ENABLE_MASK;
-	if (data[RTC_MONTH] & 0xf)
-		data[RTC_MONTH] |= (1 << ALARM_ENABLE_SHIFT);
-	if (data[RTC_YEAR] & info->drv_data->mask)
-		data[RTC_YEAR] |= (1 << ALARM_ENABLE_SHIFT);
-	if (data[RTC_DATE] & 0x1f)
-		data[RTC_DATE] |= (1 << ALARM_ENABLE_SHIFT);
+		max77686_rtc_data_to_tm(data, &tm, info);
+
+		data[RTC_SEC] |= (1 << ALARM_ENABLE_SHIFT);
+		data[RTC_MIN] |= (1 << ALARM_ENABLE_SHIFT);
+		data[RTC_HOUR] |= (1 << ALARM_ENABLE_SHIFT);
+		data[RTC_WEEKDAY] &= ~ALARM_ENABLE_MASK;
+		if (data[RTC_MONTH] & 0xf)
+			data[RTC_MONTH] |= (1 << ALARM_ENABLE_SHIFT);
+		if (data[RTC_YEAR] & info->drv_data->mask)
+			data[RTC_YEAR] |= (1 << ALARM_ENABLE_SHIFT);
+		if (data[RTC_DATE] & 0x1f)
+			data[RTC_DATE] |= (1 << ALARM_ENABLE_SHIFT);
+
+		ret = regmap_bulk_write(info->max77686->rtc_regmap,
+					map[REG_ALARM1_SEC], data,
+					ARRAY_SIZE(data));
+	} else {
+		ret = regmap_write(info->max77686->regmap, map[REG_RTC_AE1],
+				   MAX77802_ALARM_ENABLE_VALUE);
+	}
 
-	ret = regmap_bulk_write(info->max77686->rtc_regmap,
-				map[REG_ALARM1_SEC], data, ARRAY_SIZE(data));
 	if (ret < 0) {
 		dev_err(info->dev, "%s: fail to write alarm reg(%d)\n",
 				__func__, ret);
@@ -413,7 +525,7 @@  static int max77686_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 	u8 data[RTC_NR_TIME];
 	int ret;
 
-	ret = max77686_rtc_tm_to_data(&alrm->time, data);
+	ret = max77686_rtc_tm_to_data(&alrm->time, data, info);
 	if (ret < 0)
 		return ret;
 
@@ -524,6 +636,9 @@  static int max77686_rtc_probe(struct platform_device *pdev)
 	info->drv_data = (const struct max77686_rtc_driver_data *)
 		id->driver_data;
 
+	if (!info->drv_data->separate_i2c_addr)
+		info->max77686->rtc_regmap = info->max77686->regmap;
+
 	platform_set_drvdata(pdev, info);
 
 	ret = max77686_rtc_init_reg(info);
@@ -535,7 +650,7 @@  static int max77686_rtc_probe(struct platform_device *pdev)
 
 	device_init_wakeup(&pdev->dev, 1);
 
-	info->rtc_dev = devm_rtc_device_register(&pdev->dev, "max77686-rtc",
+	info->rtc_dev = devm_rtc_device_register(&pdev->dev, id->name,
 					&max77686_rtc_ops, THIS_MODULE);
 
 	if (IS_ERR(info->rtc_dev)) {
@@ -598,6 +713,7 @@  static SIMPLE_DEV_PM_OPS(max77686_rtc_pm_ops,
 
 static const struct platform_device_id rtc_id[] = {
 	{ "max77686-rtc", .driver_data = (kernel_ulong_t)&max77686_drv_data, },
+	{ "max77802-rtc", .driver_data = (kernel_ulong_t)&max77802_drv_data, },
 	{},
 };
 MODULE_DEVICE_TABLE(platform, rtc_id);