mfd: pf1550: Add core driver for the PF1550 PMIC

There are 3 sub-devices for which the drivers will be added in
subsequent patches.

Signed-off-by: Samuel Kayode <samuel.kayode@savoirfairelinux.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Tested-by: Sean Nyekjaer <sean@geanix.com>
Link: https://patch.msgid.link/20251001-pf1550-v12-2-a3302aa41687@savoirfairelinux.com
Signed-off-by: Lee Jones <lee@kernel.org>

Author: skayodesfl

drivers/mfd/Kconfig

@@ -605,6 +605,22 @@ config MFD_MX25_TSADC
 	  i.MX25 processors. They consist of a conversion queue for general
 	  purpose ADC and a queue for Touchscreens.
 
+config MFD_PF1550
+	tristate "NXP PF1550 PMIC Support"
+	depends on I2C=y && OF
+	select MFD_CORE
+	select REGMAP_I2C
+	select REGMAP_IRQ
+	help
+	  Say yes here to add support for NXP PF1550. This is a companion Power
+	  Management IC with regulators, onkey, and charger control on chip.
+	  This driver provides common support for accessing the device;
+	  additional drivers must be enabled in order to use the functionality
+	  of the device.
+
+	  This driver can also be built as a module and if so will be called
+	  pf1550.
+
 config MFD_HI6421_PMIC
 	tristate "HiSilicon Hi6421 PMU/Codec IC"
 	depends on OF

drivers/mfd/Makefile

@@ -122,6 +122,8 @@ obj-$(CONFIG_MFD_MC13XXX)	+= mc13xxx-core.o
 obj-$(CONFIG_MFD_MC13XXX_SPI)	+= mc13xxx-spi.o
 obj-$(CONFIG_MFD_MC13XXX_I2C)	+= mc13xxx-i2c.o
 
+obj-$(CONFIG_MFD_PF1550)	+= pf1550.o
+
 obj-$(CONFIG_MFD_NCT6694)	+= nct6694.o
 
 obj-$(CONFIG_MFD_CORE)		+= mfd-core.o

drivers/mfd/pf1550.c

@@ -0,0 +1,367 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Core driver for the PF1550
+ *
+ * Copyright (C) 2016 Freescale Semiconductor, Inc.
+ * Robin Gong <yibin.gong@freescale.com>
+ *
+ * Portions Copyright (c) 2025 Savoir-faire Linux Inc.
+ * Samuel Kayode <samuel.kayode@savoirfairelinux.com>
+ */
+
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/pf1550.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
+
+static const struct regmap_config pf1550_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = PF1550_PMIC_REG_END,
+};
+
+static const struct regmap_irq pf1550_irqs[] = {
+	REGMAP_IRQ_REG(PF1550_IRQ_CHG, 0, IRQ_CHG),
+	REGMAP_IRQ_REG(PF1550_IRQ_REGULATOR, 0, IRQ_REGULATOR),
+	REGMAP_IRQ_REG(PF1550_IRQ_ONKEY, 0, IRQ_ONKEY),
+};
+
+static const struct regmap_irq_chip pf1550_irq_chip = {
+	.name = "pf1550",
+	.status_base = PF1550_PMIC_REG_INT_CATEGORY,
+	.init_ack_masked = 1,
+	.num_regs = 1,
+	.irqs = pf1550_irqs,
+	.num_irqs = ARRAY_SIZE(pf1550_irqs),
+};
+
+static const struct regmap_irq pf1550_regulator_irqs[] = {
+	REGMAP_IRQ_REG(PF1550_PMIC_IRQ_SW1_LS, 0, PMIC_IRQ_SW1_LS),
+	REGMAP_IRQ_REG(PF1550_PMIC_IRQ_SW2_LS, 0, PMIC_IRQ_SW2_LS),
+	REGMAP_IRQ_REG(PF1550_PMIC_IRQ_SW3_LS, 0, PMIC_IRQ_SW3_LS),
+	REGMAP_IRQ_REG(PF1550_PMIC_IRQ_SW1_HS, 3, PMIC_IRQ_SW1_HS),
+	REGMAP_IRQ_REG(PF1550_PMIC_IRQ_SW2_HS, 3, PMIC_IRQ_SW2_HS),
+	REGMAP_IRQ_REG(PF1550_PMIC_IRQ_SW3_HS, 3, PMIC_IRQ_SW3_HS),
+	REGMAP_IRQ_REG(PF1550_PMIC_IRQ_LDO1_FAULT, 16, PMIC_IRQ_LDO1_FAULT),
+	REGMAP_IRQ_REG(PF1550_PMIC_IRQ_LDO2_FAULT, 16, PMIC_IRQ_LDO2_FAULT),
+	REGMAP_IRQ_REG(PF1550_PMIC_IRQ_LDO3_FAULT, 16, PMIC_IRQ_LDO3_FAULT),
+	REGMAP_IRQ_REG(PF1550_PMIC_IRQ_TEMP_110, 24, PMIC_IRQ_TEMP_110),
+	REGMAP_IRQ_REG(PF1550_PMIC_IRQ_TEMP_125, 24, PMIC_IRQ_TEMP_125),
+};
+
+static const struct regmap_irq_chip pf1550_regulator_irq_chip = {
+	.name = "pf1550-regulator",
+	.status_base = PF1550_PMIC_REG_SW_INT_STAT0,
+	.ack_base = PF1550_PMIC_REG_SW_INT_STAT0,
+	.mask_base = PF1550_PMIC_REG_SW_INT_MASK0,
+	.use_ack = 1,
+	.init_ack_masked = 1,
+	.num_regs = 25,
+	.irqs = pf1550_regulator_irqs,
+	.num_irqs = ARRAY_SIZE(pf1550_regulator_irqs),
+};
+
+static const struct resource regulator_resources[] = {
+	DEFINE_RES_IRQ(PF1550_PMIC_IRQ_SW1_LS),
+	DEFINE_RES_IRQ(PF1550_PMIC_IRQ_SW2_LS),
+	DEFINE_RES_IRQ(PF1550_PMIC_IRQ_SW3_LS),
+	DEFINE_RES_IRQ(PF1550_PMIC_IRQ_SW1_HS),
+	DEFINE_RES_IRQ(PF1550_PMIC_IRQ_SW2_HS),
+	DEFINE_RES_IRQ(PF1550_PMIC_IRQ_SW3_HS),
+	DEFINE_RES_IRQ(PF1550_PMIC_IRQ_LDO1_FAULT),
+	DEFINE_RES_IRQ(PF1550_PMIC_IRQ_LDO2_FAULT),
+	DEFINE_RES_IRQ(PF1550_PMIC_IRQ_LDO3_FAULT),
+	DEFINE_RES_IRQ(PF1550_PMIC_IRQ_TEMP_110),
+	DEFINE_RES_IRQ(PF1550_PMIC_IRQ_TEMP_125),
+};
+
+static const struct regmap_irq pf1550_onkey_irqs[] = {
+	REGMAP_IRQ_REG(PF1550_ONKEY_IRQ_PUSHI, 0, ONKEY_IRQ_PUSHI),
+	REGMAP_IRQ_REG(PF1550_ONKEY_IRQ_1SI, 0, ONKEY_IRQ_1SI),
+	REGMAP_IRQ_REG(PF1550_ONKEY_IRQ_2SI, 0, ONKEY_IRQ_2SI),
+	REGMAP_IRQ_REG(PF1550_ONKEY_IRQ_3SI, 0, ONKEY_IRQ_3SI),
+	REGMAP_IRQ_REG(PF1550_ONKEY_IRQ_4SI, 0, ONKEY_IRQ_4SI),
+	REGMAP_IRQ_REG(PF1550_ONKEY_IRQ_8SI, 0, ONKEY_IRQ_8SI),
+};
+
+static const struct regmap_irq_chip pf1550_onkey_irq_chip = {
+	.name = "pf1550-onkey",
+	.status_base = PF1550_PMIC_REG_ONKEY_INT_STAT0,
+	.ack_base = PF1550_PMIC_REG_ONKEY_INT_STAT0,
+	.mask_base = PF1550_PMIC_REG_ONKEY_INT_MASK0,
+	.use_ack = 1,
+	.init_ack_masked = 1,
+	.num_regs = 1,
+	.irqs = pf1550_onkey_irqs,
+	.num_irqs = ARRAY_SIZE(pf1550_onkey_irqs),
+};
+
+static const struct resource onkey_resources[] = {
+	DEFINE_RES_IRQ(PF1550_ONKEY_IRQ_PUSHI),
+	DEFINE_RES_IRQ(PF1550_ONKEY_IRQ_1SI),
+	DEFINE_RES_IRQ(PF1550_ONKEY_IRQ_2SI),
+	DEFINE_RES_IRQ(PF1550_ONKEY_IRQ_3SI),
+	DEFINE_RES_IRQ(PF1550_ONKEY_IRQ_4SI),
+	DEFINE_RES_IRQ(PF1550_ONKEY_IRQ_8SI),
+};
+
+static const struct regmap_irq pf1550_charger_irqs[] = {
+	REGMAP_IRQ_REG(PF1550_CHARG_IRQ_BAT2SOCI, 0, CHARG_IRQ_BAT2SOCI),
+	REGMAP_IRQ_REG(PF1550_CHARG_IRQ_BATI, 0, CHARG_IRQ_BATI),
+	REGMAP_IRQ_REG(PF1550_CHARG_IRQ_CHGI, 0, CHARG_IRQ_CHGI),
+	REGMAP_IRQ_REG(PF1550_CHARG_IRQ_VBUSI, 0, CHARG_IRQ_VBUSI),
+	REGMAP_IRQ_REG(PF1550_CHARG_IRQ_THMI, 0, CHARG_IRQ_THMI),
+};
+
+static const struct regmap_irq_chip pf1550_charger_irq_chip = {
+	.name = "pf1550-charger",
+	.status_base = PF1550_CHARG_REG_CHG_INT,
+	.ack_base = PF1550_CHARG_REG_CHG_INT,
+	.mask_base = PF1550_CHARG_REG_CHG_INT_MASK,
+	.use_ack = 1,
+	.init_ack_masked = 1,
+	.num_regs = 1,
+	.irqs = pf1550_charger_irqs,
+	.num_irqs = ARRAY_SIZE(pf1550_charger_irqs),
+};
+
+static const struct resource charger_resources[] = {
+	DEFINE_RES_IRQ(PF1550_CHARG_IRQ_BAT2SOCI),
+	DEFINE_RES_IRQ(PF1550_CHARG_IRQ_BATI),
+	DEFINE_RES_IRQ(PF1550_CHARG_IRQ_CHGI),
+	DEFINE_RES_IRQ(PF1550_CHARG_IRQ_VBUSI),
+	DEFINE_RES_IRQ(PF1550_CHARG_IRQ_THMI),
+};
+
+static const struct mfd_cell pf1550_regulator_cell = {
+	.name = "pf1550-regulator",
+	.num_resources = ARRAY_SIZE(regulator_resources),
+	.resources = regulator_resources,
+};
+
+static const struct mfd_cell pf1550_onkey_cell = {
+	.name = "pf1550-onkey",
+	.num_resources = ARRAY_SIZE(onkey_resources),
+	.resources = onkey_resources,
+};
+
+static const struct mfd_cell pf1550_charger_cell = {
+	.name = "pf1550-charger",
+	.num_resources = ARRAY_SIZE(charger_resources),
+	.resources = charger_resources,
+};
+
+/*
+ * The PF1550 is shipped in variants of A0, A1,...A9. Each variant defines a
+ * configuration of the PMIC in a One-Time Programmable (OTP) memory.
+ * This memory is accessed indirectly by writing valid keys to specific
+ * registers of the PMIC. To read the OTP memory after writing the valid keys,
+ * the OTP register address to be read is written to pf1550 register 0xc4 and
+ * its value read from pf1550 register 0xc5.
+ */
+static int pf1550_read_otp(const struct pf1550_ddata *pf1550, unsigned int index,
+			   unsigned int *val)
+{
+	int ret = 0;
+
+	ret = regmap_write(pf1550->regmap, PF1550_PMIC_REG_KEY, PF1550_OTP_PMIC_KEY);
+	if (ret)
+		goto read_err;
+
+	ret = regmap_write(pf1550->regmap, PF1550_CHARG_REG_CHGR_KEY2, PF1550_OTP_CHGR_KEY);
+	if (ret)
+		goto read_err;
+
+	ret = regmap_write(pf1550->regmap, PF1550_TEST_REG_KEY3, PF1550_OTP_TEST_KEY);
+	if (ret)
+		goto read_err;
+
+	ret = regmap_write(pf1550->regmap, PF1550_TEST_REG_FMRADDR, index);
+	if (ret)
+		goto read_err;
+
+	ret = regmap_read(pf1550->regmap, PF1550_TEST_REG_FMRDATA, val);
+	if (ret)
+		goto read_err;
+
+	return 0;
+
+read_err:
+	return dev_err_probe(pf1550->dev, ret, "OTP reg %x not found!\n", index);
+}
+
+static int pf1550_i2c_probe(struct i2c_client *i2c)
+{
+	const struct mfd_cell *regulator = &pf1550_regulator_cell;
+	const struct mfd_cell *charger = &pf1550_charger_cell;
+	const struct mfd_cell *onkey = &pf1550_onkey_cell;
+	unsigned int reg_data = 0, otp_data = 0;
+	struct pf1550_ddata *pf1550;
+	struct irq_domain *domain;
+	int irq, ret = 0;
+
+	pf1550 = devm_kzalloc(&i2c->dev, sizeof(*pf1550), GFP_KERNEL);
+	if (!pf1550)
+		return -ENOMEM;
+
+	i2c_set_clientdata(i2c, pf1550);
+	pf1550->dev = &i2c->dev;
+	pf1550->irq = i2c->irq;
+
+	pf1550->regmap = devm_regmap_init_i2c(i2c, &pf1550_regmap_config);
+	if (IS_ERR(pf1550->regmap))
+		return dev_err_probe(pf1550->dev, PTR_ERR(pf1550->regmap),
+				     "failed to allocate register map\n");
+
+	ret = regmap_read(pf1550->regmap, PF1550_PMIC_REG_DEVICE_ID, &reg_data);
+	if (ret < 0)
+		return dev_err_probe(pf1550->dev, ret, "cannot read chip ID\n");
+	if (reg_data != PF1550_DEVICE_ID)
+		return dev_err_probe(pf1550->dev, -ENODEV, "invalid device ID: 0x%02x\n", reg_data);
+
+	/* Regulator DVS for SW2 */
+	ret = pf1550_read_otp(pf1550, PF1550_OTP_SW2_SW3, &otp_data);
+	if (ret)
+		return ret;
+
+	/* When clear, DVS should be enabled */
+	if (!(otp_data & OTP_SW2_DVS_ENB))
+		pf1550->dvs2_enable = true;
+
+	/* Regulator DVS for SW1 */
+	ret = pf1550_read_otp(pf1550, PF1550_OTP_SW1_SW2, &otp_data);
+	if (ret)
+		return ret;
+
+	if (!(otp_data & OTP_SW1_DVS_ENB))
+		pf1550->dvs1_enable = true;
+
+	/* Add top level interrupts */
+	ret = devm_regmap_add_irq_chip(pf1550->dev, pf1550->regmap, pf1550->irq,
+				       IRQF_ONESHOT | IRQF_SHARED |
+				       IRQF_TRIGGER_FALLING,
+				       0, &pf1550_irq_chip,
+				       &pf1550->irq_data);
+	if (ret)
+		return ret;
+
+	/* Add regulator */
+	irq = regmap_irq_get_virq(pf1550->irq_data, PF1550_IRQ_REGULATOR);
+	if (irq < 0)
+		return dev_err_probe(pf1550->dev, irq,
+				     "Failed to get parent vIRQ(%d) for chip %s\n",
+				     PF1550_IRQ_REGULATOR, pf1550_irq_chip.name);
+
+	ret = devm_regmap_add_irq_chip(pf1550->dev, pf1550->regmap, irq,
+				       IRQF_ONESHOT | IRQF_SHARED |
+				       IRQF_TRIGGER_FALLING, 0,
+				       &pf1550_regulator_irq_chip,
+				       &pf1550->irq_data_regulator);
+	if (ret)
+		return dev_err_probe(pf1550->dev, ret, "Failed to add %s IRQ chip\n",
+				     pf1550_regulator_irq_chip.name);
+
+	domain = regmap_irq_get_domain(pf1550->irq_data_regulator);
+
+	ret = devm_mfd_add_devices(pf1550->dev, PLATFORM_DEVID_NONE, regulator, 1, NULL, 0, domain);
+	if (ret)
+		return ret;
+
+	/* Add onkey */
+	irq = regmap_irq_get_virq(pf1550->irq_data, PF1550_IRQ_ONKEY);
+	if (irq < 0)
+		return dev_err_probe(pf1550->dev, irq,
+				     "Failed to get parent vIRQ(%d) for chip %s\n",
+				     PF1550_IRQ_ONKEY, pf1550_irq_chip.name);
+
+	ret = devm_regmap_add_irq_chip(pf1550->dev, pf1550->regmap, irq,
+				       IRQF_ONESHOT | IRQF_SHARED |
+				       IRQF_TRIGGER_FALLING, 0,
+				       &pf1550_onkey_irq_chip,
+				       &pf1550->irq_data_onkey);
+	if (ret)
+		return dev_err_probe(pf1550->dev, ret, "Failed to add %s IRQ chip\n",
+				     pf1550_onkey_irq_chip.name);
+
+	domain = regmap_irq_get_domain(pf1550->irq_data_onkey);
+
+	ret = devm_mfd_add_devices(pf1550->dev, PLATFORM_DEVID_NONE, onkey, 1, NULL, 0, domain);
+	if (ret)
+		return ret;
+
+	/* Add battery charger */
+	irq = regmap_irq_get_virq(pf1550->irq_data, PF1550_IRQ_CHG);
+	if (irq < 0)
+		return dev_err_probe(pf1550->dev, irq,
+				     "Failed to get parent vIRQ(%d) for chip %s\n",
+				     PF1550_IRQ_CHG, pf1550_irq_chip.name);
+
+	ret = devm_regmap_add_irq_chip(pf1550->dev, pf1550->regmap, irq,
+				       IRQF_ONESHOT | IRQF_SHARED |
+				       IRQF_TRIGGER_FALLING, 0,
+				       &pf1550_charger_irq_chip,
+				       &pf1550->irq_data_charger);
+	if (ret)
+		return dev_err_probe(pf1550->dev, ret, "Failed to add %s IRQ chip\n",
+				     pf1550_charger_irq_chip.name);
+
+	domain = regmap_irq_get_domain(pf1550->irq_data_charger);
+
+	return devm_mfd_add_devices(pf1550->dev, PLATFORM_DEVID_NONE, charger, 1, NULL, 0, domain);
+}
+
+static int pf1550_suspend(struct device *dev)
+{
+	struct pf1550_ddata *pf1550 = dev_get_drvdata(dev);
+
+	if (device_may_wakeup(dev)) {
+		enable_irq_wake(pf1550->irq);
+		disable_irq(pf1550->irq);
+	}
+
+	return 0;
+}
+
+static int pf1550_resume(struct device *dev)
+{
+	struct pf1550_ddata *pf1550 = dev_get_drvdata(dev);
+
+	if (device_may_wakeup(dev)) {
+		disable_irq_wake(pf1550->irq);
+		enable_irq(pf1550->irq);
+	}
+
+	return 0;
+}
+static DEFINE_SIMPLE_DEV_PM_OPS(pf1550_pm, pf1550_suspend, pf1550_resume);
+
+static const struct i2c_device_id pf1550_i2c_id[] = {
+	{ "pf1550" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(i2c, pf1550_i2c_id);
+
+static const struct of_device_id pf1550_dt_match[] = {
+	{ .compatible = "nxp,pf1550" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, pf1550_dt_match);
+
+static struct i2c_driver pf1550_i2c_driver = {
+	.driver = {
+		   .name = "pf1550",
+		   .pm = pm_sleep_ptr(&pf1550_pm),
+		   .of_match_table = pf1550_dt_match,
+	},
+	.probe = pf1550_i2c_probe,
+	.id_table = pf1550_i2c_id,
+};
+module_i2c_driver(pf1550_i2c_driver);
+
+MODULE_DESCRIPTION("NXP PF1550 core driver");
+MODULE_AUTHOR("Robin Gong <yibin.gong@freescale.com>");
+MODULE_LICENSE("GPL");