From: Aman Kumar Pandey <aman.kumarpandey@nxp.com>
Add core MFD support for the NXP P3H2x4x (P3H2440/P3H2441/P3H2840/P3H2841)
family of multiport I3C hub devices. These devices connect to a host via
I3C/I2C/SMBus and expose multiple downstream target ports.
Signed-off-by: Aman Kumar Pandey <aman.kumarpandey@nxp.com>
Signed-off-by: Vikash Bansal <vikash.bansal@nxp.com>
---
Changes in v8:
- No change
Changes in v7:
- Use new config I3C_OR_I2C
Changes in v6:
- No change
Changes in v5:
- Corrected the ordering in the Makefile and Kconfig for MFD_P3H2X4X
- 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)
- Added support for NXP P3H2x4x MFD functionality
---
---
MAINTAINERS | 2 +
drivers/mfd/Kconfig | 13 ++++
drivers/mfd/Makefile | 1 +
drivers/mfd/p3h2840.c | 125 ++++++++++++++++++++++++++++++++++++
include/linux/mfd/p3h2840.h | 27 ++++++++
5 files changed, 168 insertions(+)
create mode 100644 drivers/mfd/p3h2840.c
create mode 100644 include/linux/mfd/p3h2840.h
diff --git a/MAINTAINERS b/MAINTAINERS
index c72976dbdf31..4f67fe64c833 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -19101,6 +19101,8 @@ L: linux-kernel@vger.kernel.org
L: linux-i3c-owner@lists.infradead.org
S: Maintained
F: Documentation/devicetree/bindings/i3c/nxp,p3h2840.yaml
+F: drivers/mfd/p3h2840.c
+F: include/linux/mfd/p3h2840.h
NXP PF5300/PF5301/PF5302 PMIC REGULATOR DEVICE DRIVER
M: Woodrow Douglass <wdouglass@carnegierobotics.com>
diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 7192c9d1d268..14f4736683a1 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -617,6 +617,19 @@ config MFD_MX25_TSADC
i.MX25 processors. They consist of a conversion queue for general
purpose ADC and a queue for Touchscreens.
+config MFD_P3H2X4X
+ tristate "NXP P3H2X4X I3C Hub Device"
+ depends on I3C_OR_I2C
+ select MFD_CORE
+ select REGMAP_I3C
+ select REGMAP_I2C
+ help
+ Enable Support for NXP P3H244x/P3H284x I3C HUB device using I3C/I2C
+ communication interface.
+
+ This driver provides support for I3C hub and regulator, each subdriver
+ can be enabled independently depending on the required functionality.
+
config MFD_PF1550
tristate "NXP PF1550 PMIC Support"
depends on I2C=y && OF
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index e75e8045c28a..aaadf50fedf4 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -122,6 +122,7 @@ 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_P3H2X4X) += p3h2840.o
obj-$(CONFIG_MFD_PF1550) += pf1550.o
obj-$(CONFIG_MFD_NCT6694) += nct6694.o
diff --git a/drivers/mfd/p3h2840.c b/drivers/mfd/p3h2840.c
new file mode 100644
index 000000000000..65090a09f7c6
--- /dev/null
+++ b/drivers/mfd/p3h2840.c
@@ -0,0 +1,125 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2025 NXP
+ * P3H2x4x i3c hub and regulator device.
+ */
+
+#include <linux/i3c/master.h>
+#include <linux/i2c.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/p3h2840.h>
+#include <linux/regmap.h>
+
+static const struct mfd_cell p3h2x4x_devs[] = {
+ {
+ .name = "p3h2x4x-regulator",
+ },
+ {
+ .name = "p3h2x4x-i3c-hub",
+ },
+};
+
+static const struct regmap_config p3h2x4x_regmap_config = {
+ .reg_bits = P3H2x4x_REG_BITS,
+ .val_bits = P3H2x4x_VAL_BITS,
+ .max_register = 0xFF,
+};
+
+static int p3h2x4x_device_probe_i3c(struct i3c_device *i3cdev)
+{
+ struct p3h2x4x_dev *p3h2x4x;
+ int ret;
+
+ p3h2x4x = devm_kzalloc(&i3cdev->dev, sizeof(*p3h2x4x), GFP_KERNEL);
+ if (!p3h2x4x)
+ return -ENOMEM;
+
+ i3cdev_set_drvdata(i3cdev, p3h2x4x);
+
+ p3h2x4x->regmap = devm_regmap_init_i3c(i3cdev, &p3h2x4x_regmap_config);
+ if (IS_ERR(p3h2x4x->regmap))
+ return dev_err_probe(&i3cdev->dev, PTR_ERR(p3h2x4x->regmap),
+ "Failed to register I3C HUB regmap\n");
+
+ p3h2x4x->is_p3h2x4x_in_i3c = true;
+ p3h2x4x->i3cdev = i3cdev;
+
+ ret = devm_mfd_add_devices(&i3cdev->dev, PLATFORM_DEVID_NONE,
+ p3h2x4x_devs, ARRAY_SIZE(p3h2x4x_devs),
+ NULL, 0, NULL);
+ if (ret)
+ return dev_err_probe(&i3cdev->dev, ret, "Failed to add sub devices\n");
+
+ return 0;
+}
+
+static int p3h2x4x_device_probe_i2c(struct i2c_client *client)
+{
+ struct p3h2x4x_dev *p3h2x4x;
+ int ret;
+
+ p3h2x4x = devm_kzalloc(&client->dev, sizeof(*p3h2x4x), GFP_KERNEL);
+ if (!p3h2x4x)
+ return -ENOMEM;
+
+ i2c_set_clientdata(client, p3h2x4x);
+
+ p3h2x4x->regmap = devm_regmap_init_i2c(client, &p3h2x4x_regmap_config);
+ if (IS_ERR(p3h2x4x->regmap))
+ return dev_err_probe(&client->dev, PTR_ERR(p3h2x4x->regmap),
+ "Failed to register I3C HUB regmap\n");
+
+ p3h2x4x->is_p3h2x4x_in_i3c = false;
+
+ ret = devm_mfd_add_devices(&client->dev, PLATFORM_DEVID_NONE,
+ p3h2x4x_devs, ARRAY_SIZE(p3h2x4x_devs),
+ NULL, 0, NULL);
+ if (ret)
+ return dev_err_probe(&client->dev, ret, "Failed to add sub devices\n");
+
+ return 0;
+}
+
+/* p3h2x4x ids (i3c) */
+static const struct i3c_device_id p3h2x4x_i3c_ids[] = {
+ I3C_CLASS(I3C_DCR_HUB, NULL),
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(i3c, p3h2x4x_i3c_ids);
+
+/* p3h2x4x ids (i2c) */
+static const struct i2c_device_id p3h2x4x_i2c_id_table[] = {
+ { "nxp-i3c-hub" },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(i2c, p3h2x4x_i2c_id_table);
+
+static const struct of_device_id p3h2x4x_i2c_of_match[] = {
+ { .compatible = "nxp,p3h2840", },
+ { /* sentinel */ }
+};
+
+MODULE_DEVICE_TABLE(of, p3h2x4x_i2c_of_match);
+static struct i3c_driver p3h2x4x_i3c = {
+ .driver = {
+ .name = "p3h2x4x_i3c_drv",
+ },
+ .probe = p3h2x4x_device_probe_i3c,
+ .id_table = p3h2x4x_i3c_ids,
+};
+
+static struct i2c_driver p3h2x4x_i2c = {
+ .driver = {
+ .name = "p3h2x4x_i2c_drv",
+ .of_match_table = p3h2x4x_i2c_of_match,
+ },
+ .probe = p3h2x4x_device_probe_i2c,
+ .id_table = p3h2x4x_i2c_id_table,
+};
+
+module_i3c_i2c_driver(p3h2x4x_i3c, &p3h2x4x_i2c);
+
+MODULE_AUTHOR("Aman Kumar Pandey <aman.kumarpandey@nxp.com>");
+MODULE_AUTHOR("Vikash Bansal <vikash.bansal@nxp.com>");
+MODULE_DESCRIPTION("P3H2x4x I3C HUB multi function driver");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/mfd/p3h2840.h b/include/linux/mfd/p3h2840.h
new file mode 100644
index 000000000000..cba6fa516d1e
--- /dev/null
+++ b/include/linux/mfd/p3h2840.h
@@ -0,0 +1,27 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright 2025 NXP
+ * This header file contain private Reg address and its bit mapping etc.
+ */
+
+#ifndef _LINUX_MFD_P3H2840_H
+#define _LINUX_MFD_P3H2840_H
+
+#include <linux/types.h>
+
+/* Device Configuration Registers */
+#define P3H2x4x_DEV_REG_PROTECTION_CODE 0x10
+#define P3H2x4x_REGISTERS_LOCK_CODE 0x00
+#define P3H2x4x_REGISTERS_UNLOCK_CODE 0x69
+#define P3H2x4x_CP1_REGISTERS_UNLOCK_CODE 0x6a
+
+/* Reg config for Regmap */
+#define P3H2x4x_REG_BITS 8
+#define P3H2x4x_VAL_BITS 8
+
+struct p3h2x4x_dev {
+ struct i3c_device *i3cdev;
+ struct regmap *regmap;
+ bool is_p3h2x4x_in_i3c;
+};
+#endif /* _LINUX_MFD_P3H2840_H */
--
2.25.1
On Mon, 23 Mar 2026, Lakshay Piplani wrote:
> From: Aman Kumar Pandey <aman.kumarpandey@nxp.com>
>
> Add core MFD support for the NXP P3H2x4x (P3H2440/P3H2441/P3H2840/P3H2841)
> family of multiport I3C hub devices. These devices connect to a host via
> I3C/I2C/SMBus and expose multiple downstream target ports.
>
> Signed-off-by: Aman Kumar Pandey <aman.kumarpandey@nxp.com>
> Signed-off-by: Vikash Bansal <vikash.bansal@nxp.com>
>
> ---
> Changes in v8:
> - No change
>
> Changes in v7:
> - Use new config I3C_OR_I2C
>
> Changes in v6:
> - No change
>
> Changes in v5:
> - Corrected the ordering in the Makefile and Kconfig for MFD_P3H2X4X
> - 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)
> - Added support for NXP P3H2x4x MFD functionality
> ---
> ---
> MAINTAINERS | 2 +
> drivers/mfd/Kconfig | 13 ++++
> drivers/mfd/Makefile | 1 +
> drivers/mfd/p3h2840.c | 125 ++++++++++++++++++++++++++++++++++++
> include/linux/mfd/p3h2840.h | 27 ++++++++
> 5 files changed, 168 insertions(+)
> create mode 100644 drivers/mfd/p3h2840.c
> create mode 100644 include/linux/mfd/p3h2840.h
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index c72976dbdf31..4f67fe64c833 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -19101,6 +19101,8 @@ L: linux-kernel@vger.kernel.org
> L: linux-i3c-owner@lists.infradead.org
> S: Maintained
> F: Documentation/devicetree/bindings/i3c/nxp,p3h2840.yaml
> +F: drivers/mfd/p3h2840.c
> +F: include/linux/mfd/p3h2840.h
>
> NXP PF5300/PF5301/PF5302 PMIC REGULATOR DEVICE DRIVER
> M: Woodrow Douglass <wdouglass@carnegierobotics.com>
> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> index 7192c9d1d268..14f4736683a1 100644
> --- a/drivers/mfd/Kconfig
> +++ b/drivers/mfd/Kconfig
> @@ -617,6 +617,19 @@ config MFD_MX25_TSADC
> i.MX25 processors. They consist of a conversion queue for general
> purpose ADC and a queue for Touchscreens.
>
> +config MFD_P3H2X4X
> + tristate "NXP P3H2X4X I3C Hub Device"
> + depends on I3C_OR_I2C
> + select MFD_CORE
> + select REGMAP_I3C
> + select REGMAP_I2C
Please use a single tab to indent config attributes, and a tab plus two spaces
for the help text.
Also, if 'I3C' is disabled but 'I2C' is enabled, unconditionally selecting
'REGMAP_I3C' could result in unmet dependencies. Should these selects be made
conditional?
> + help
> + Enable Support for NXP P3H244x/P3H284x I3C HUB device using I3C/I2C
> + communication interface.
> +
> + This driver provides support for I3C hub and regulator, each subdriver
> + can be enabled independently depending on the required functionality.
> +
> config MFD_PF1550
> tristate "NXP PF1550 PMIC Support"
> depends on I2C=y && OF
> diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
> index e75e8045c28a..aaadf50fedf4 100644
> --- a/drivers/mfd/Makefile
> +++ b/drivers/mfd/Makefile
> @@ -122,6 +122,7 @@ 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_P3H2X4X) += p3h2840.o
No spaces before tabs.
> obj-$(CONFIG_MFD_PF1550) += pf1550.o
>
> obj-$(CONFIG_MFD_NCT6694) += nct6694.o
> diff --git a/drivers/mfd/p3h2840.c b/drivers/mfd/p3h2840.c
> new file mode 100644
> index 000000000000..65090a09f7c6
> --- /dev/null
> +++ b/drivers/mfd/p3h2840.c
> @@ -0,0 +1,125 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright 2025 NXP
This is quite out of date at this point.
> + * P3H2x4x i3c hub and regulator device.
> + */
> +
> +#include <linux/i3c/master.h>
> +#include <linux/i2c.h>
> +#include <linux/mfd/core.h>
> +#include <linux/mfd/p3h2840.h>
> +#include <linux/regmap.h>
Alphabetical.
> +static const struct mfd_cell p3h2x4x_devs[] = {
> + {
> + .name = "p3h2x4x-regulator",
> + },
> + {
> + .name = "p3h2x4x-i3c-hub",
> + },
> +};
> +
> +static const struct regmap_config p3h2x4x_regmap_config = {
> + .reg_bits = P3H2x4x_REG_BITS,
Please use standard uppercase for macro names (e.g., 'P3H2X4X_REG_BITS').
> + .val_bits = P3H2x4x_VAL_BITS,
> + .max_register = 0xFF,
> +};
> +
> +static int p3h2x4x_device_probe_i3c(struct i3c_device *i3cdev)
This probe function and 'p3h2x4x_device_probe_i2c()' are nearly identical.
Could we refactor the common logic into a single generic helper function?
> +{
> + struct p3h2x4x_dev *p3h2x4x;
> + int ret;
> +
> + p3h2x4x = devm_kzalloc(&i3cdev->dev, sizeof(*p3h2x4x), GFP_KERNEL);
> + if (!p3h2x4x)
> + return -ENOMEM;
> +
> + i3cdev_set_drvdata(i3cdev, p3h2x4x);
> +
> + p3h2x4x->regmap = devm_regmap_init_i3c(i3cdev, &p3h2x4x_regmap_config);
> + if (IS_ERR(p3h2x4x->regmap))
> + return dev_err_probe(&i3cdev->dev, PTR_ERR(p3h2x4x->regmap),
> + "Failed to register I3C HUB regmap\n");
> +
> + p3h2x4x->is_p3h2x4x_in_i3c = true;
> + p3h2x4x->i3cdev = i3cdev;
> +
> + ret = devm_mfd_add_devices(&i3cdev->dev, PLATFORM_DEVID_NONE,
Why are you using PLATFORM_DEVID_NONE here instead of *_AUTO?
> + p3h2x4x_devs, ARRAY_SIZE(p3h2x4x_devs),
> + NULL, 0, NULL);
> + if (ret)
> + return dev_err_probe(&i3cdev->dev, ret, "Failed to add sub devices\n");
> +
> + return 0;
> +}
> +
> +static int p3h2x4x_device_probe_i2c(struct i2c_client *client)
> +{
> + struct p3h2x4x_dev *p3h2x4x;
> + int ret;
> +
> + p3h2x4x = devm_kzalloc(&client->dev, sizeof(*p3h2x4x), GFP_KERNEL);
> + if (!p3h2x4x)
> + return -ENOMEM;
> +
> + i2c_set_clientdata(client, p3h2x4x);
> +
> + p3h2x4x->regmap = devm_regmap_init_i2c(client, &p3h2x4x_regmap_config);
> + if (IS_ERR(p3h2x4x->regmap))
> + return dev_err_probe(&client->dev, PTR_ERR(p3h2x4x->regmap),
> + "Failed to register I3C HUB regmap\n");
I3C?
> +
> + p3h2x4x->is_p3h2x4x_in_i3c = false;
> +
> + ret = devm_mfd_add_devices(&client->dev, PLATFORM_DEVID_NONE,
> + p3h2x4x_devs, ARRAY_SIZE(p3h2x4x_devs),
> + NULL, 0, NULL);
> + if (ret)
> + return dev_err_probe(&client->dev, ret, "Failed to add sub devices\n");
> +
> + return 0;
> +}
> +
> +/* p3h2x4x ids (i3c) */
This comment doesn't add anything. Please remove it.
> +static const struct i3c_device_id p3h2x4x_i3c_ids[] = {
> + I3C_CLASS(I3C_DCR_HUB, NULL),
> + { /* sentinel */ },
> +};
> +MODULE_DEVICE_TABLE(i3c, p3h2x4x_i3c_ids);
> +
> +/* p3h2x4x ids (i2c) */
And this one.
> +static const struct i2c_device_id p3h2x4x_i2c_id_table[] = {
> + { "nxp-i3c-hub" },
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(i2c, p3h2x4x_i2c_id_table);
> +
> +static const struct of_device_id p3h2x4x_i2c_of_match[] = {
Too many spaces.
> + { .compatible = "nxp,p3h2840", },
> + { /* sentinel */ }
> +};
> +
> +MODULE_DEVICE_TABLE(of, p3h2x4x_i2c_of_match);
This needs to be moved up a line.
It's linked with 'p3h2x4x_i2c_of_match', not 'p3h2x4x_i3c'.
> +static struct i3c_driver p3h2x4x_i3c = {
> + .driver = {
> + .name = "p3h2x4x_i3c_drv",
> + },
> + .probe = p3h2x4x_device_probe_i3c,
> + .id_table = p3h2x4x_i3c_ids,
> +};
> +
> +static struct i2c_driver p3h2x4x_i2c = {
> + .driver = {
> + .name = "p3h2x4x_i2c_drv",
> + .of_match_table = p3h2x4x_i2c_of_match,
> + },
> + .probe = p3h2x4x_device_probe_i2c,
> + .id_table = p3h2x4x_i2c_id_table,
> +};
> +
> +module_i3c_i2c_driver(p3h2x4x_i3c, &p3h2x4x_i2c);
> +
> +MODULE_AUTHOR("Aman Kumar Pandey <aman.kumarpandey@nxp.com>");
> +MODULE_AUTHOR("Vikash Bansal <vikash.bansal@nxp.com>");
> +MODULE_DESCRIPTION("P3H2x4x I3C HUB multi function driver");
> +MODULE_LICENSE("GPL");
> diff --git a/include/linux/mfd/p3h2840.h b/include/linux/mfd/p3h2840.h
> new file mode 100644
> index 000000000000..cba6fa516d1e
> --- /dev/null
> +++ b/include/linux/mfd/p3h2840.h
> @@ -0,0 +1,27 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
These should use // in header files.
> +/*
> + * Copyright 2025 NXP
> + * This header file contain private Reg address and its bit mapping etc.
> + */
> +
> +#ifndef _LINUX_MFD_P3H2840_H
> +#define _LINUX_MFD_P3H2840_H
> +
> +#include <linux/types.h>
> +
> +/* Device Configuration Registers */
> +#define P3H2x4x_DEV_REG_PROTECTION_CODE 0x10
> +#define P3H2x4x_REGISTERS_LOCK_CODE 0x00
> +#define P3H2x4x_REGISTERS_UNLOCK_CODE 0x69
> +#define P3H2x4x_CP1_REGISTERS_UNLOCK_CODE 0x6a
Could we use standard uppercase for all macro names (e.g., 'P3H2X4X_')?
> +
> +/* Reg config for Regmap */
> +#define P3H2x4x_REG_BITS 8
> +#define P3H2x4x_VAL_BITS 8
> +
> +struct p3h2x4x_dev {
> + struct i3c_device *i3cdev;
> + struct regmap *regmap;
> + bool is_p3h2x4x_in_i3c;
> +};
Which attributes do the child drivers actually use?
--
Lee Jones [李琼斯]
On Tue, 31 Mar 2026, Lee Jones wrote: > On Mon, 23 Mar 2026, Lakshay Piplani wrote: > > > From: Aman Kumar Pandey <aman.kumarpandey@nxp.com> > > > > Add core MFD support for the NXP P3H2x4x (P3H2440/P3H2441/P3H2840/P3H2841) > > family of multiport I3C hub devices. These devices connect to a host via > > I3C/I2C/SMBus and expose multiple downstream target ports. > > > > Signed-off-by: Aman Kumar Pandey <aman.kumarpandey@nxp.com> > > Signed-off-by: Vikash Bansal <vikash.bansal@nxp.com> > > > > --- > > Changes in v8: > > - No change > > > > Changes in v7: > > - Use new config I3C_OR_I2C > > > > Changes in v6: > > - No change > > > > Changes in v5: > > - Corrected the ordering in the Makefile and Kconfig for MFD_P3H2X4X > > - 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) > > - Added support for NXP P3H2x4x MFD functionality > > --- > > --- > > MAINTAINERS | 2 + > > drivers/mfd/Kconfig | 13 ++++ > > drivers/mfd/Makefile | 1 + > > drivers/mfd/p3h2840.c | 125 ++++++++++++++++++++++++++++++++++++ > > include/linux/mfd/p3h2840.h | 27 ++++++++ > > 5 files changed, 168 insertions(+) > > create mode 100644 drivers/mfd/p3h2840.c > > create mode 100644 include/linux/mfd/p3h2840.h [...] > > diff --git a/include/linux/mfd/p3h2840.h b/include/linux/mfd/p3h2840.h > > new file mode 100644 > > index 000000000000..cba6fa516d1e > > --- /dev/null > > +++ b/include/linux/mfd/p3h2840.h > > @@ -0,0 +1,27 @@ > > +/* SPDX-License-Identifier: GPL-2.0 */ > > These should use // in header files. Ignore this. I've lead you astray there. -- Lee Jones [李琼斯]
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