[PATCH v13 4/7] regulator: p3h2x4x: Add driver for on-die regulators in NXP P3H2x4x i3c hub

Lakshay Piplani <[email protected]>
Newsgroups org.infradead.lists.linux-i3c,org.kernel.vger.linux-devicetree,org.kernel.vger.linux-kernel
Message-ID <[email protected]> 
From: Aman Kumar Pandey <[email protected]>

The NXP P3H2x4x family integrates on-die regulators alongside I3C hub
functionality. This driver registers the regulators using the MFD
framework and exposes them via the regulator subsystem.

Signed-off-by: Aman Kumar Pandey <[email protected]>
Signed-off-by: Vikash Bansal <[email protected]>
Signed-off-by: Lakshay Piplani <[email protected]>
Reviewed-by: Frank Li <[email protected]>
Reviewed-by: Mark Brown <[email protected]>

---
Changes in v13:
 - Serialize register unlock/modify/lock sequences using a device-level mutex to 
   avoid races between regulators.
 - Ensure proper module auto-loading by adding platform device ID table.
 - Improve error handling in register guard paths to avoid operating on locked hub.

Changes in v12:
 - No change

Changes in v11:
 - No change, added Reviewed-By tag

Changes in v10:
 - No change

Changes in v9:
 - No change

Changes in v8:
 - No change

Changes in v7:
 - No change, added Reviewed-By tag

Changes in v6:
 - Use DEFINE_LOCK_GUARD_1 for reg lock/unlock

Changes in v5:
 - Updated dev_err_probe() for regmap_init failure.
 - Updated module description

Changes in v4:
 - Split the driver into three separate patches (mfd, regulator and I3C hub)
 - Introduced driver for on-die regulators in NXP P3H2x4x I3C hub
---
---
 MAINTAINERS                                   |   1 +
 drivers/regulator/Kconfig                     |  10 +
 drivers/regulator/Makefile                    |   1 +
 drivers/regulator/p3h2840_i3c_hub_regulator.c | 240 ++++++++++++++++++
 4 files changed, 252 insertions(+)
 create mode 100644 drivers/regulator/p3h2840_i3c_hub_regulator.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 3420701a75c5..fcb3917aa096 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -19312,6 +19312,7 @@ L:	[email protected]
 S:	Maintained
 F:	Documentation/devicetree/bindings/i3c/nxp,p3h2840.yaml
 F:	drivers/mfd/p3h2840.c
+F:	drivers/regulator/p3h2840_i3c_hub_regulator.c
 F:	include/linux/mfd/p3h2840.h
 
 NXP PF5300/PF5301/PF5302 PMIC REGULATOR DEVICE DRIVER
diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index d71dac9436e3..88809f493fd4 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -1019,6 +1019,16 @@ config REGULATOR_MTK_DVFSRC
 	  of Mediatek. It allows for voting on regulator state
 	  between multiple users.
 
+config REGULATOR_P3H2X4X
+       tristate "NXP P3H2X4X regulator support"
+       depends on MFD_P3H2X4X
+       help
+         This driver provides support for the voltage regulators of the
+         P3H244x/P3H284x multi-function I3C Hub device.
+
+         Say M here if you want to include support for this regulator as
+         a module. The module will be named "p3h2840_i3c_hub_regulator".
+
 config REGULATOR_PALMAS
 	tristate "TI Palmas PMIC Regulators"
 	depends on MFD_PALMAS
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index 35639f3115fd..46f586ccde63 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -128,6 +128,7 @@ obj-$(CONFIG_REGULATOR_QCOM_RPMH) += qcom-rpmh-regulator.o
 obj-$(CONFIG_REGULATOR_QCOM_SMD_RPM) += qcom_smd-regulator.o
 obj-$(CONFIG_REGULATOR_QCOM_SPMI) += qcom_spmi-regulator.o
 obj-$(CONFIG_REGULATOR_QCOM_USB_VBUS) += qcom_usb_vbus-regulator.o
+obj-$(CONFIG_REGULATOR_P3H2X4X) += p3h2840_i3c_hub_regulator.o
 obj-$(CONFIG_REGULATOR_PALMAS) += palmas-regulator.o
 obj-$(CONFIG_REGULATOR_PCA9450) += pca9450-regulator.o
 obj-$(CONFIG_REGULATOR_PF0900) += pf0900-regulator.o
diff --git a/drivers/regulator/p3h2840_i3c_hub_regulator.c b/drivers/regulator/p3h2840_i3c_hub_regulator.c
new file mode 100644
index 000000000000..781622a6ff46
--- /dev/null
+++ b/drivers/regulator/p3h2840_i3c_hub_regulator.c
@@ -0,0 +1,240 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2025-2026 NXP
+ * This P3H2X4X driver file contain functions for enable/disable regulator and voltage set/get.
+ */
+#include <linux/bitfield.h>
+#include <linux/cleanup.h>
+#include <linux/mfd/p3h2840.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/regulator/driver.h>
+
+#define P3H2X4X_LDO_AND_PULLUP_CONF				0x19
+#define P3H2X4X_LDO_ENABLE_DISABLE_MASK				GENMASK(3, 0)
+#define P3H2X4X_CP0_EN_LDO				        BIT(0)
+#define P3H2X4X_CP1_EN_LDO				        BIT(1)
+#define P3H2X4X_TP0145_EN_LDO					BIT(2)
+#define P3H2X4X_TP2367_EN_LDO					BIT(3)
+
+#define P3H2X4X_NET_OPER_MODE_CONF				0x15
+#define P3H2X4X_VCCIO_LDO_CONF					0x16
+#define P3H2X4X_CP0_VCCIO_LDO_VOLTAGE_MASK			GENMASK(1, 0)
+#define P3H2X4X_CP0_VCCIO_LDO_VOLTAGE(x)	\
+		FIELD_PREP(P3H2X4X_CP0_VCCIO_LDO_VOLTAGE_MASK, x)
+#define P3H2X4X_CP1_VCCIO_LDO_VOLTAGE_MASK			GENMASK(3, 2)
+#define P3H2X4X_CP1_VCCIO_LDO_VOLTAGE(x)	\
+		FIELD_PREP(P3H2X4X_CP1_VCCIO_LDO_VOLTAGE_MASK, x)
+#define P3H2X4X_TP0145_VCCIO_LDO_VOLTAGE_MASK			GENMASK(5, 4)
+#define P3H2X4X_TP0145_VCCIO_LDO_VOLTAGE(x)	\
+		FIELD_PREP(P3H2X4X_TP0145_VCCIO_LDO_VOLTAGE_MASK, x)
+#define P3H2X4X_TP2367_VCCIO_LDO_VOLTAGE_MASK			GENMASK(7, 6)
+#define P3H2X4X_TP2367_VCCIO_LDO_VOLTAGE(x)	\
+		FIELD_PREP(P3H2X4X_TP2367_VCCIO_LDO_VOLTAGE_MASK, x)
+#define P3H2X4X_LDO_COUNT					4
+
+struct p3h2x4x_regulator_dev {
+	struct regulator_dev *rp3h2x4x_dev[P3H2X4X_LDO_COUNT];
+	struct regmap *regmap;
+	struct mutex lock; /* Serializes register unlock/restore sequences. */
+};
+
+struct p3h2x4x_reg_state {
+	unsigned int orig;
+	bool restore;
+};
+
+static void p3h2x4x_reg_guard_enter(struct regulator_dev *rdev,
+				    struct p3h2x4x_reg_state *state)
+{
+	struct p3h2x4x_regulator_dev *priv = rdev_get_drvdata(rdev);
+
+	mutex_lock(&priv->lock);
+	state->restore = false;
+
+	if (regmap_read(rdev->regmap,
+			P3H2X4X_DEV_REG_PROTECTION_CODE,
+			&state->orig)) {
+		mutex_unlock(&priv->lock);
+		return;
+	}
+
+	if (state->orig != P3H2X4X_REGISTERS_UNLOCK_CODE) {
+		regmap_write(rdev->regmap,
+			     P3H2X4X_DEV_REG_PROTECTION_CODE,
+			     P3H2X4X_REGISTERS_UNLOCK_CODE);
+		state->restore = true;
+	}
+}
+
+static void p3h2x4x_reg_guard_exit(struct regulator_dev *rdev,
+				   struct p3h2x4x_reg_state *state)
+{
+	struct p3h2x4x_regulator_dev *priv = rdev_get_drvdata(rdev);
+
+	if (state->restore)
+		regmap_write(rdev->regmap,
+			     P3H2X4X_DEV_REG_PROTECTION_CODE,
+			     state->orig);
+
+	mutex_unlock(&priv->lock);
+}
+
+DEFINE_LOCK_GUARD_1(p3h2x4x_reg, struct regulator_dev,
+		    p3h2x4x_reg_guard_enter(_T->lock, &_T->state),
+		    p3h2x4x_reg_guard_exit(_T->lock, &_T->state),
+		    struct p3h2x4x_reg_state state);
+
+static int p3h2x4x_regulator_enable(struct regulator_dev *rdev)
+{
+	guard(p3h2x4x_reg)(rdev);
+	return regulator_enable_regmap(rdev);
+}
+
+static int p3h2x4x_regulator_disable(struct regulator_dev *rdev)
+{
+	guard(p3h2x4x_reg)(rdev);
+	return regulator_disable_regmap(rdev);
+}
+
+static int p3h2x4x_regulator_set_voltage_sel(struct regulator_dev *rdev,
+					     unsigned int sel)
+{
+	guard(p3h2x4x_reg)(rdev);
+	return regulator_set_voltage_sel_regmap(rdev, sel);
+}
+
+static const struct regulator_ops p3h2x4x_ldo_ops = {
+	.list_voltage = regulator_list_voltage_table,
+	.map_voltage = regulator_map_voltage_iterate,
+	.set_voltage_sel = p3h2x4x_regulator_set_voltage_sel,
+	.get_voltage_sel = regulator_get_voltage_sel_regmap,
+	.enable = p3h2x4x_regulator_enable,
+	.disable = p3h2x4x_regulator_disable,
+	.is_enabled = regulator_is_enabled_regmap,
+};
+
+static const unsigned int p3h2x4x_voltage_table[] = {
+	1000000,
+	1100000,
+	1200000,
+	1800000,
+};
+
+static struct regulator_desc p3h2x4x_regulators[] = {
+	{
+		.name = "ldo-cp0",
+		.of_match = of_match_ptr("ldo-cp0"),
+		.regulators_node = of_match_ptr("regulators"),
+		.volt_table = p3h2x4x_voltage_table,
+		.n_voltages = ARRAY_SIZE(p3h2x4x_voltage_table),
+		.ops = &p3h2x4x_ldo_ops,
+		.type = REGULATOR_VOLTAGE,
+		.owner = THIS_MODULE,
+		.enable_reg = P3H2X4X_LDO_AND_PULLUP_CONF,
+		.enable_mask = P3H2X4X_CP0_EN_LDO,
+		.vsel_reg = P3H2X4X_VCCIO_LDO_CONF,
+		.vsel_mask = P3H2X4X_CP0_VCCIO_LDO_VOLTAGE_MASK,
+	},
+	{
+		.name = "ldo-cp1",
+		.of_match = of_match_ptr("ldo-cp1"),
+		.regulators_node = of_match_ptr("regulators"),
+		.volt_table = p3h2x4x_voltage_table,
+		.n_voltages = ARRAY_SIZE(p3h2x4x_voltage_table),
+		.ops = &p3h2x4x_ldo_ops,
+		.type = REGULATOR_VOLTAGE,
+		.owner = THIS_MODULE,
+		.enable_reg = P3H2X4X_LDO_AND_PULLUP_CONF,
+		.enable_mask = P3H2X4X_CP1_EN_LDO,
+		.vsel_reg = P3H2X4X_VCCIO_LDO_CONF,
+		.vsel_mask = P3H2X4X_CP1_VCCIO_LDO_VOLTAGE_MASK,
+	},
+	{
+		.name = "ldo-tpg0",
+		.of_match = of_match_ptr("ldo-tpg0"),
+		.regulators_node = of_match_ptr("regulators"),
+		.volt_table = p3h2x4x_voltage_table,
+		.n_voltages = ARRAY_SIZE(p3h2x4x_voltage_table),
+		.ops = &p3h2x4x_ldo_ops,
+		.type = REGULATOR_VOLTAGE,
+		.owner = THIS_MODULE,
+		.enable_reg = P3H2X4X_LDO_AND_PULLUP_CONF,
+		.enable_mask = P3H2X4X_TP0145_EN_LDO,
+		.vsel_reg = P3H2X4X_VCCIO_LDO_CONF,
+		.vsel_mask = P3H2X4X_TP0145_VCCIO_LDO_VOLTAGE_MASK,
+	},
+	{
+		.name = "ldo-tpg1",
+		.of_match = of_match_ptr("ldo-tpg1"),
+		.regulators_node = of_match_ptr("regulators"),
+		.volt_table = p3h2x4x_voltage_table,
+		.n_voltages = ARRAY_SIZE(p3h2x4x_voltage_table),
+		.ops = &p3h2x4x_ldo_ops,
+		.type = REGULATOR_VOLTAGE,
+		.owner = THIS_MODULE,
+		.enable_reg = P3H2X4X_LDO_AND_PULLUP_CONF,
+		.enable_mask = P3H2X4X_TP2367_EN_LDO,
+		.vsel_reg = P3H2X4X_VCCIO_LDO_CONF,
+		.vsel_mask = P3H2X4X_TP2367_VCCIO_LDO_VOLTAGE_MASK,
+	},
+};
+
+static int p3h2x4x_regulator_probe(struct platform_device *pdev)
+{
+	struct p3h2x4x_dev *p3h2x4x = dev_get_drvdata(pdev->dev.parent);
+	struct p3h2x4x_regulator_dev *p3h2x4x_regulator;
+	struct regulator_config rcfg = { };
+	struct device *dev = &pdev->dev;
+	struct regulator_dev *rdev;
+	int i, ret;
+
+	p3h2x4x_regulator = devm_kzalloc(dev, sizeof(*p3h2x4x_regulator), GFP_KERNEL);
+	if (!p3h2x4x_regulator)
+		return -ENOMEM;
+
+	ret = devm_mutex_init(dev, &p3h2x4x_regulator->lock);
+	if (ret)
+		return ret;
+
+	platform_set_drvdata(pdev, p3h2x4x_regulator);
+
+	p3h2x4x_regulator->regmap = p3h2x4x->regmap;
+	device_set_of_node_from_dev(dev, dev->parent);
+
+	rcfg.dev = dev;
+	rcfg.regmap = p3h2x4x_regulator->regmap;
+	rcfg.driver_data = p3h2x4x_regulator;
+
+	for (i = 0; i < ARRAY_SIZE(p3h2x4x_regulators); i++) {
+		rdev = devm_regulator_register(&pdev->dev, &p3h2x4x_regulators[i], &rcfg);
+		if (IS_ERR(rdev))
+			return dev_err_probe(dev, PTR_ERR(rdev), "Failed to register %s\n",
+					     p3h2x4x_regulators[i].name);
+		p3h2x4x_regulator->rp3h2x4x_dev[i] = rdev;
+	}
+	return 0;
+}
+
+static const struct platform_device_id p3h2x4x_regulator_id[] = {
+	{ "p3h2x4x-regulator" },
+	{ }
+};
+MODULE_DEVICE_TABLE(platform, p3h2x4x_regulator_id);
+
+static struct platform_driver p3h2x4x_regulator_driver = {
+	.driver = {
+		.name = "p3h2x4x-regulator",
+		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
+	},
+	.probe = p3h2x4x_regulator_probe,
+	.id_table = p3h2x4x_regulator_id,
+};
+module_platform_driver(p3h2x4x_regulator_driver);
+
+MODULE_AUTHOR("Aman Kumar Pandey <[email protected]>");
+MODULE_AUTHOR("Vikash Bansal <[email protected]>");
+MODULE_AUTHOR("Lakshay Piplani <[email protected]>");
+MODULE_DESCRIPTION("NXP P3H2X4X I3C HUB Regulator driver");
+MODULE_LICENSE("GPL");
-- 
2.25.1


-- 
linux-i3c mailing list
[email protected]
http://lists.infradead.org/mailman/listinfo/linux-i3c
lmpx.com only provides a reader for public news (NNTP) servers. It is not affiliated with the servers or forums shown here and is not responsible for the content of articles, which is written by their respective authors.