diff --git a/MAINTAINERS b/MAINTAINERS
index 9c381b4a1db4..af152de0436b 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -543,6 +543,8 @@ L:	linux-gpio@vger.kernel.org
 L:	linux-pwm@vger.kernel.org
 S:	Maintained
 F:	Documentation/devicetree/bindings/*/adi,adp5585*.yaml
+F:	drivers/mfd/adp5585.c
+F:	include/linux/mfd/adp5585.h
 
 ADP5588 QWERTY KEYPAD AND IO EXPANDER DRIVER (ADP5588/ADP5587)
 M:	Michael Hennerich <michael.hennerich@analog.com>
diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index bc8be2e593b6..f9325bcce1b9 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -20,6 +20,18 @@ config MFD_CS5535
 	  This is the core driver for CS5535/CS5536 MFD functions.  This is
 	  necessary for using the board's GPIO and MFGPT functionality.
 
+config MFD_ADP5585
+	tristate "Analog Devices ADP5585 keypad decoder and I/O expander driver"
+	select MFD_CORE
+	select REGMAP_I2C
+	depends on I2C
+	depends on OF || COMPILE_TEST
+	help
+	  Say yes here to add support for the Analog Devices ADP5585 GPIO
+	  expander, PWM and keypad controller. This includes the I2C driver and
+	  the core APIs _only_, you have to select individual components like
+	  the GPIO and PWM functions under the corresponding menus.
+
 config MFD_ALTERA_A10SR
 	bool "Altera Arria10 DevKit System Resource chip"
 	depends on ARCH_INTEL_SOCFPGA && SPI_MASTER=y && OF
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index 02b651cd7535..2a9f91e81af8 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -193,6 +193,7 @@ obj-$(CONFIG_MFD_DB8500_PRCMU)	+= db8500-prcmu.o
 obj-$(CONFIG_AB8500_CORE)	+= ab8500-core.o ab8500-sysctrl.o
 obj-$(CONFIG_MFD_TIMBERDALE)    += timberdale.o
 obj-$(CONFIG_PMIC_ADP5520)	+= adp5520.o
+obj-$(CONFIG_MFD_ADP5585)	+= adp5585.o
 obj-$(CONFIG_MFD_KEMPLD)	+= kempld-core.o
 obj-$(CONFIG_MFD_INTEL_QUARK_I2C_GPIO)	+= intel_quark_i2c_gpio.o
 obj-$(CONFIG_LPC_SCH)		+= lpc_sch.o
diff --git a/drivers/mfd/adp5585.c b/drivers/mfd/adp5585.c
new file mode 100644
index 000000000000..160e0b38106a
--- /dev/null
+++ b/drivers/mfd/adp5585.c
@@ -0,0 +1,205 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Analog Devices ADP5585 I/O expander, PWM controller and keypad controller
+ *
+ * Copyright 2022 NXP
+ * Copyright 2024 Ideas on Board Oy
+ */
+
+#include <linux/array_size.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/mfd/adp5585.h>
+#include <linux/mfd/core.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/types.h>
+
+static const struct mfd_cell adp5585_devs[] = {
+	{ .name = "adp5585-gpio", },
+	{ .name = "adp5585-pwm", },
+};
+
+static const struct regmap_range adp5585_volatile_ranges[] = {
+	regmap_reg_range(ADP5585_ID, ADP5585_GPI_STATUS_B),
+};
+
+static const struct regmap_access_table adp5585_volatile_regs = {
+	.yes_ranges = adp5585_volatile_ranges,
+	.n_yes_ranges = ARRAY_SIZE(adp5585_volatile_ranges),
+};
+
+/*
+ * Chip variants differ in the default configuration of pull-up and pull-down
+ * resistors, and therefore have different default register values:
+ *
+ * - The -00, -01 and -03 variants (collectively referred to as
+ *   ADP5585_REGMAP_00) have pull-up on all GPIO pins by default.
+ * - The -02 variant has no default pull-up or pull-down resistors.
+ * - The -04 variant has default pull-down resistors on all GPIO pins.
+ */
+
+static const u8 adp5585_regmap_defaults_00[ADP5585_MAX_REG + 1] = {
+	/* 0x00 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	/* 0x08 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	/* 0x10 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	/* 0x18 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	/* 0x20 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	/* 0x28 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	/* 0x30 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	/* 0x38 */ 0x00, 0x00, 0x00, 0x00, 0x00,
+};
+
+static const u8 adp5585_regmap_defaults_02[ADP5585_MAX_REG + 1] = {
+	/* 0x00 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	/* 0x08 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	/* 0x10 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xc3,
+	/* 0x18 */ 0x03, 0x00, 0x03, 0x00, 0x00, 0x00, 0x00, 0x00,
+	/* 0x20 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	/* 0x28 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	/* 0x30 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	/* 0x38 */ 0x00, 0x00, 0x00, 0x00, 0x00,
+};
+
+static const u8 adp5585_regmap_defaults_04[ADP5585_MAX_REG + 1] = {
+	/* 0x00 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	/* 0x08 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	/* 0x10 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x55,
+	/* 0x18 */ 0x05, 0x55, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00,
+	/* 0x20 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	/* 0x28 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	/* 0x30 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	/* 0x38 */ 0x00, 0x00, 0x00, 0x00, 0x00,
+};
+
+enum adp5585_regmap_type {
+	ADP5585_REGMAP_00,
+	ADP5585_REGMAP_02,
+	ADP5585_REGMAP_04,
+};
+
+static const struct regmap_config adp5585_regmap_configs[] = {
+	[ADP5585_REGMAP_00] = {
+		.reg_bits = 8,
+		.val_bits = 8,
+		.max_register = ADP5585_MAX_REG,
+		.volatile_table = &adp5585_volatile_regs,
+		.cache_type = REGCACHE_MAPLE,
+		.reg_defaults_raw = adp5585_regmap_defaults_00,
+		.num_reg_defaults_raw = sizeof(adp5585_regmap_defaults_00),
+	},
+	[ADP5585_REGMAP_02] = {
+		.reg_bits = 8,
+		.val_bits = 8,
+		.max_register = ADP5585_MAX_REG,
+		.volatile_table = &adp5585_volatile_regs,
+		.cache_type = REGCACHE_MAPLE,
+		.reg_defaults_raw = adp5585_regmap_defaults_02,
+		.num_reg_defaults_raw = sizeof(adp5585_regmap_defaults_02),
+	},
+	[ADP5585_REGMAP_04] = {
+		.reg_bits = 8,
+		.val_bits = 8,
+		.max_register = ADP5585_MAX_REG,
+		.volatile_table = &adp5585_volatile_regs,
+		.cache_type = REGCACHE_MAPLE,
+		.reg_defaults_raw = adp5585_regmap_defaults_04,
+		.num_reg_defaults_raw = sizeof(adp5585_regmap_defaults_04),
+	},
+};
+
+static int adp5585_i2c_probe(struct i2c_client *i2c)
+{
+	const struct regmap_config *regmap_config;
+	struct adp5585_dev *adp5585;
+	unsigned int id;
+	int ret;
+
+	adp5585 = devm_kzalloc(&i2c->dev, sizeof(*adp5585), GFP_KERNEL);
+	if (!adp5585)
+		return -ENOMEM;
+
+	i2c_set_clientdata(i2c, adp5585);
+
+	regmap_config = i2c_get_match_data(i2c);
+	adp5585->regmap = devm_regmap_init_i2c(i2c, regmap_config);
+	if (IS_ERR(adp5585->regmap))
+		return dev_err_probe(&i2c->dev, PTR_ERR(adp5585->regmap),
+				     "Failed to initialize register map\n");
+
+	ret = regmap_read(adp5585->regmap, ADP5585_ID, &id);
+	if (ret)
+		return dev_err_probe(&i2c->dev, ret,
+				     "Failed to read device ID\n");
+
+	if ((id & ADP5585_MAN_ID_MASK) != ADP5585_MAN_ID_VALUE)
+		return dev_err_probe(&i2c->dev, -ENODEV,
+				     "Invalid device ID 0x%02x\n", id);
+
+	ret = devm_mfd_add_devices(&i2c->dev, PLATFORM_DEVID_AUTO,
+				   adp5585_devs, ARRAY_SIZE(adp5585_devs),
+				   NULL, 0, NULL);
+	if (ret)
+		return dev_err_probe(&i2c->dev, ret,
+				     "Failed to add child devices\n");
+
+	return 0;
+}
+
+static int adp5585_suspend(struct device *dev)
+{
+	struct adp5585_dev *adp5585 = dev_get_drvdata(dev);
+
+	regcache_cache_only(adp5585->regmap, true);
+
+	return 0;
+}
+
+static int adp5585_resume(struct device *dev)
+{
+	struct adp5585_dev *adp5585 = dev_get_drvdata(dev);
+
+	regcache_cache_only(adp5585->regmap, false);
+	regcache_mark_dirty(adp5585->regmap);
+
+	return regcache_sync(adp5585->regmap);
+}
+
+static DEFINE_SIMPLE_DEV_PM_OPS(adp5585_pm, adp5585_suspend, adp5585_resume);
+
+static const struct of_device_id adp5585_of_match[] = {
+	{
+		.compatible = "adi,adp5585-00",
+		.data = &adp5585_regmap_configs[ADP5585_REGMAP_00],
+	}, {
+		.compatible = "adi,adp5585-01",
+		.data = &adp5585_regmap_configs[ADP5585_REGMAP_00],
+	}, {
+		.compatible = "adi,adp5585-02",
+		.data = &adp5585_regmap_configs[ADP5585_REGMAP_02],
+	}, {
+		.compatible = "adi,adp5585-03",
+		.data = &adp5585_regmap_configs[ADP5585_REGMAP_00],
+	}, {
+		.compatible = "adi,adp5585-04",
+		.data = &adp5585_regmap_configs[ADP5585_REGMAP_04],
+	},
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, adp5585_of_match);
+
+static struct i2c_driver adp5585_i2c_driver = {
+	.driver = {
+		.name = "adp5585",
+		.of_match_table = adp5585_of_match,
+		.pm = pm_sleep_ptr(&adp5585_pm),
+	},
+	.probe = adp5585_i2c_probe,
+};
+module_i2c_driver(adp5585_i2c_driver);
+
+MODULE_DESCRIPTION("ADP5585 core driver");
+MODULE_AUTHOR("Haibo Chen <haibo.chen@nxp.com>");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/mfd/adp5585.h b/include/linux/mfd/adp5585.h
new file mode 100644
index 000000000000..016033cd68e4
--- /dev/null
+++ b/include/linux/mfd/adp5585.h
@@ -0,0 +1,126 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Analog Devices ADP5585 I/O expander, PWM controller and keypad controller
+ *
+ * Copyright 2022 NXP
+ * Copyright 2024 Ideas on Board Oy
+ */
+
+#ifndef __MFD_ADP5585_H_
+#define __MFD_ADP5585_H_
+
+#include <linux/bits.h>
+
+#define ADP5585_ID			0x00
+#define		ADP5585_MAN_ID_VALUE		0x20
+#define		ADP5585_MAN_ID_MASK		GENMASK(7, 4)
+#define ADP5585_INT_STATUS		0x01
+#define ADP5585_STATUS			0x02
+#define ADP5585_FIFO_1			0x03
+#define ADP5585_FIFO_2			0x04
+#define ADP5585_FIFO_3			0x05
+#define ADP5585_FIFO_4			0x06
+#define ADP5585_FIFO_5			0x07
+#define ADP5585_FIFO_6			0x08
+#define ADP5585_FIFO_7			0x09
+#define ADP5585_FIFO_8			0x0a
+#define ADP5585_FIFO_9			0x0b
+#define ADP5585_FIFO_10			0x0c
+#define ADP5585_FIFO_11			0x0d
+#define ADP5585_FIFO_12			0x0e
+#define ADP5585_FIFO_13			0x0f
+#define ADP5585_FIFO_14			0x10
+#define ADP5585_FIFO_15			0x11
+#define ADP5585_FIFO_16			0x12
+#define ADP5585_GPI_INT_STAT_A		0x13
+#define ADP5585_GPI_INT_STAT_B		0x14
+#define ADP5585_GPI_STATUS_A		0x15
+#define ADP5585_GPI_STATUS_B		0x16
+#define ADP5585_RPULL_CONFIG_A		0x17
+#define ADP5585_RPULL_CONFIG_B		0x18
+#define ADP5585_RPULL_CONFIG_C		0x19
+#define ADP5585_RPULL_CONFIG_D		0x1a
+#define		ADP5585_Rx_PULL_CFG_PU_300K	0
+#define		ADP5585_Rx_PULL_CFG_PD_300K	1
+#define		ADP5585_Rx_PULL_CFG_PU_100K	2
+#define		ADP5585_Rx_PULL_CFG_DISABLE	3
+#define		ADP5585_Rx_PULL_CFG_MASK	3
+#define ADP5585_GPI_INT_LEVEL_A		0x1b
+#define ADP5585_GPI_INT_LEVEL_B		0x1c
+#define ADP5585_GPI_EVENT_EN_A		0x1d
+#define ADP5585_GPI_EVENT_EN_B		0x1e
+#define ADP5585_GPI_INTERRUPT_EN_A	0x1f
+#define ADP5585_GPI_INTERRUPT_EN_B	0x20
+#define ADP5585_DEBOUNCE_DIS_A		0x21
+#define ADP5585_DEBOUNCE_DIS_B		0x22
+#define ADP5585_GPO_DATA_OUT_A		0x23
+#define ADP5585_GPO_DATA_OUT_B		0x24
+#define ADP5585_GPO_OUT_MODE_A		0x25
+#define ADP5585_GPO_OUT_MODE_B		0x26
+#define ADP5585_GPIO_DIRECTION_A	0x27
+#define ADP5585_GPIO_DIRECTION_B	0x28
+#define ADP5585_RESET1_EVENT_A		0x29
+#define ADP5585_RESET1_EVENT_B		0x2a
+#define ADP5585_RESET1_EVENT_C		0x2b
+#define ADP5585_RESET2_EVENT_A		0x2c
+#define ADP5585_RESET2_EVENT_B		0x2d
+#define ADP5585_RESET_CFG		0x2e
+#define ADP5585_PWM_OFFT_LOW		0x2f
+#define ADP5585_PWM_OFFT_HIGH		0x30
+#define ADP5585_PWM_ONT_LOW		0x31
+#define ADP5585_PWM_ONT_HIGH		0x32
+#define ADP5585_PWM_CFG			0x33
+#define		ADP5585_PWM_IN_AND		BIT(2)
+#define		ADP5585_PWM_MODE		BIT(1)
+#define		ADP5585_PWM_EN			BIT(0)
+#define ADP5585_LOGIC_CFG		0x34
+#define ADP5585_LOGIC_FF_CFG		0x35
+#define ADP5585_LOGIC_INT_EVENT_EN	0x36
+#define ADP5585_POLL_PTIME_CFG		0x37
+#define ADP5585_PIN_CONFIG_A		0x38
+#define ADP5585_PIN_CONFIG_B		0x39
+#define ADP5585_PIN_CONFIG_C		0x3a
+#define		ADP5585_PULL_SELECT		BIT(7)
+#define		ADP5585_C4_EXTEND_CFG_GPIO11	(0U << 6)
+#define		ADP5585_C4_EXTEND_CFG_RESET2	(1U << 6)
+#define		ADP5585_C4_EXTEND_CFG_MASK	GENMASK(6, 6)
+#define		ADP5585_R4_EXTEND_CFG_GPIO5	(0U << 5)
+#define		ADP5585_R4_EXTEND_CFG_RESET1	(1U << 5)
+#define		ADP5585_R4_EXTEND_CFG_MASK	GENMASK(5, 5)
+#define		ADP5585_R3_EXTEND_CFG_GPIO4	(0U << 2)
+#define		ADP5585_R3_EXTEND_CFG_LC	(1U << 2)
+#define		ADP5585_R3_EXTEND_CFG_PWM_OUT	(2U << 2)
+#define		ADP5585_R3_EXTEND_CFG_MASK	GENMASK(3, 2)
+#define		ADP5585_R0_EXTEND_CFG_GPIO1	(0U << 0)
+#define		ADP5585_R0_EXTEND_CFG_LY	(1U << 0)
+#define		ADP5585_R0_EXTEND_CFG_MASK	GENMASK(0, 0)
+#define ADP5585_GENERAL_CFG		0x3b
+#define		ADP5585_OSC_EN			BIT(7)
+#define		ADP5585_OSC_FREQ_50KHZ		(0U << 5)
+#define		ADP5585_OSC_FREQ_100KHZ		(1U << 5)
+#define		ADP5585_OSC_FREQ_200KHZ		(2U << 5)
+#define		ADP5585_OSC_FREQ_500KHZ		(3U << 5)
+#define		ADP5585_OSC_FREQ_MASK		GENMASK(6, 5)
+#define		ADP5585_INT_CFG			BIT(1)
+#define		ADP5585_RST_CFG			BIT(0)
+#define ADP5585_INT_EN			0x3c
+
+#define ADP5585_MAX_REG			ADP5585_INT_EN
+
+/*
+ * Bank 0 covers pins "GPIO 1/R0" to "GPIO 6/R5", numbered 0 to 5 by the
+ * driver, and bank 1 covers pins "GPIO 7/C0" to "GPIO 11/C4", numbered 6 to
+ * 10. Some variants of the ADP5585 don't support "GPIO 6/R5". As the driver
+ * uses identical GPIO numbering for all variants to avoid confusion, GPIO 5 is
+ * marked as reserved in the device tree for variants that don't support it.
+ */
+#define ADP5585_BANK(n)			((n) >= 6 ? 1 : 0)
+#define ADP5585_BIT(n)			((n) >= 6 ? BIT((n) - 6) : BIT(n))
+
+struct regmap;
+
+struct adp5585_dev {
+	struct regmap *regmap;
+};
+
+#endif