rtc: bd70528: Support BD72720 rtc

The BD72720 has similar RTC block as a few other ROHM PMICs.

Add support for BD72720 RTC.

Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://patch.msgid.link/3241773f0f8e8d8e591a8e948495686cfdee4875.1765804226.git.mazziesaccount@gmail.com
Signed-off-by: Lee Jones <lee@kernel.org>

Author: M-Vaittinen

drivers/rtc/Kconfig

@@ -570,7 +570,8 @@ config RTC_DRV_BD70528
 	depends on MFD_ROHM_BD71828
 	help
 	  If you say Y here you will get support for the RTC
-	  block on ROHM BD71815 and BD71828 Power Management IC.
+	  block on ROHM BD71815, BD71828 and BD72720 Power
+	  Management ICs.
 
 	  This driver can also be built as a module. If so, the module
 	  will be called rtc-bd70528.

drivers/rtc/rtc-bd70528.c

@@ -7,6 +7,7 @@
 #include <linux/bcd.h>
 #include <linux/mfd/rohm-bd71815.h>
 #include <linux/mfd/rohm-bd71828.h>
+#include <linux/mfd/rohm-bd72720.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
@@ -262,13 +263,13 @@ static int bd70528_probe(struct platform_device *pdev)
 
 		/*
 		 * See also BD718XX_ALM_EN_OFFSET:
-		 * This works for BD71828 and BD71815 as they have same offset
-		 * between ALM0 start and ALM0_MASK. If new ICs are to be
-		 * added this requires proper check as ALM0_MASK is not located
-		 * at the end of ALM0 block - but after all ALM blocks so if
-		 * amount of ALMs differ the offset to enable/disable is likely
-		 * to be incorrect and enable/disable must be given as own
-		 * reg address here.
+		 * This works for BD71828, BD71815, and BD72720 as they all
+		 * have same offset between the ALM0 start and the ALM0_MASK.
+		 * If new ICs are to be added this requires proper check as
+		 * the  ALM0_MASK is not located at the end of ALM0 block -
+		 * but after all ALM blocks. If amount of ALMs differ, the
+		 * offset to enable/disable is likely to be incorrect and
+		 * enable/disable must be given as own reg address here.
 		 */
 		bd_rtc->bd718xx_alm_block_start = BD71815_REG_RTC_ALM_START;
 		hour_reg = BD71815_REG_HOUR;
@@ -278,6 +279,11 @@ static int bd70528_probe(struct platform_device *pdev)
 		bd_rtc->bd718xx_alm_block_start = BD71828_REG_RTC_ALM_START;
 		hour_reg = BD71828_REG_RTC_HOUR;
 		break;
+	case ROHM_CHIP_TYPE_BD72720:
+		bd_rtc->reg_time_start = BD72720_REG_RTC_START;
+		bd_rtc->bd718xx_alm_block_start = BD72720_REG_RTC_ALM_START;
+		hour_reg = BD72720_REG_RTC_HOUR;
+		break;
 	default:
 		dev_err(&pdev->dev, "Unknown chip\n");
 		return -ENOENT;
@@ -337,6 +343,7 @@ static int bd70528_probe(struct platform_device *pdev)
 static const struct platform_device_id bd718x7_rtc_id[] = {
 	{ "bd71828-rtc", ROHM_CHIP_TYPE_BD71828 },
 	{ "bd71815-rtc", ROHM_CHIP_TYPE_BD71815 },
+	{ "bd72720-rtc", ROHM_CHIP_TYPE_BD72720 },
 	{ },
 };
 MODULE_DEVICE_TABLE(platform, bd718x7_rtc_id);