power: regulator: max9807: add regulator support

Added a new regulator driver for the MAXIM MAX8907 PMIC, providing
essential regulator functionalities and incorporated the necessary binding
framework within the core PMIC driver.

Tested-by: Ion Agorria <ion@agorria.com>
Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
diff --git a/include/power/max8907.h b/include/power/max8907.h
new file mode 100644
index 0000000..a19b25f
--- /dev/null
+++ b/include/power/max8907.h
@@ -0,0 +1,73 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ *  Copyright(C) 2024 Svyatoslav Ryhel <clamor95@gmail.com>
+ */
+
+#ifndef _MAX8907_H_
+#define _MAX8907_H_
+
+#define MAX8907_LDO_NUM			20
+#define MAX8907_SD_NUM			3
+
+/* Drivers name */
+#define MAX8907_LDO_DRIVER		"max8907_ldo"
+#define MAX8907_SD_DRIVER		"max8907_sd"
+
+/* MAX8907 register map */
+#define MAX8907_REG_SDCTL1		0x04
+#define MAX8907_REG_SDCTL2		0x07
+#define MAX8907_REG_SDCTL3		0x0A
+
+#define MAX8907_REG_LDOCTL16		0x10
+#define MAX8907_REG_LDOCTL17		0x14
+#define MAX8907_REG_LDOCTL1		0x18
+#define MAX8907_REG_LDOCTL2		0x1C
+#define MAX8907_REG_LDOCTL3		0x20
+#define MAX8907_REG_LDOCTL4		0x24
+#define MAX8907_REG_LDOCTL5		0x28
+#define MAX8907_REG_LDOCTL6		0x2C
+#define MAX8907_REG_LDOCTL7		0x30
+#define MAX8907_REG_LDOCTL8		0x34
+#define MAX8907_REG_LDOCTL9		0x38
+#define MAX8907_REG_LDOCTL10		0x3C
+#define MAX8907_REG_LDOCTL11		0x40
+#define MAX8907_REG_LDOCTL12		0x44
+#define MAX8907_REG_LDOCTL13		0x48
+#define MAX8907_REG_LDOCTL14		0x4C
+#define MAX8907_REG_LDOCTL15		0x50
+#define MAX8907_REG_LDOCTL19		0x5C
+#define MAX8907_REG_LDOCTL18		0x72
+#define MAX8907_REG_LDOCTL20		0x9C
+
+/* MAX8907 configuration values */
+#define MAX8907_CTL			0
+#define MAX8907_SEQCNT			1
+#define MAX8907_VOUT			2
+
+/* mask bit fields */
+#define MAX8907_MASK_LDO_SEQ		0x1C
+#define MAX8907_MASK_LDO_EN		0x01
+
+/* Step-Down (SD) Regulator calculations */
+#define SD1_VOLT_MAX			2225000
+#define SD1_VOLT_MIN			650000
+#define SD1_VOLT_STEP			25000
+
+#define SD2_VOLT_MAX			1425000
+#define SD2_VOLT_MIN			637500
+#define SD2_VOLT_STEP			12500
+
+#define SD3_VOLT_MAX			3900000
+#define SD3_VOLT_MIN			750000
+#define SD3_VOLT_STEP			50000
+
+/* Low-Dropout Linear (LDO) Regulator calculations */
+#define LDO_750_VOLT_MAX		3900000
+#define LDO_750_VOLT_MIN		750000
+#define LDO_750_VOLT_STEP		50000
+
+#define LDO_650_VOLT_MAX		2225000
+#define LDO_650_VOLT_MIN		650000
+#define LDO_650_VOLT_STEP		25000
+
+#endif /* _MAX8907_H_ */