[PATCH v13 1/1] mux: Add driver for Renesas RZ/V2H VBENCTL VBUS_SEL mux
From: Tommaso Merciai
Date: Mon Aug 10 2026 - 03:53:39 EST
As per the RZ/V2H(P) HW manual, VBUSEN can be controlled by the VBUS_SEL
bit of the VBENCTL Control Register. This register is mapped in the
reset framework. The reset driver expose this register as mux-controller
and instantiates this driver. The consumer will use the mux API to
control the VBUS_SEL bit.
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
Reviewed-by: Alvin Šipraga <alvin.sipraga@xxxxxxxxxx>
Reviewed-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>
Signed-off-by: Tommaso Merciai <tommaso.merciai.xr@xxxxxxxxxxxxxx>
---
v12->v13
- Renamed CONFIG_MUX_RZV2H_USB_VBENCTL to CONFIG_MUX_RZV2H_VBENCTL and
propagated the rename to the source file and module name.
- Dropped the unneeded "depends on OF".
- Added the missing "To compile the driver as a module" paragraph to the
Kconfig help text.
- Used the REG_FIELD() macro instead of open-coding struct reg_field, and
made it const to keep checkpatch --strict without warning.
- Used dev->parent instead of adev->dev.parent in dev_get_regmap().
- Collected Reviewed-by tags from Alvin and Prabhakar (the changes above are
cosmetic, please let me know if you want them dropped).
v11->v12
- No changes, just rebased on top of next-20260714
v10->v11:
- No changes.
v9->v10:
- No changes.
v8->v9:
- Fixed driver comment year (2025 -> 2026)
- Switch from devm_regmap_init_mmio() to dev_get_regmap().
- Drop unnecessasry include bitops.h, of.h, property.h and
drivers/reset/reset-rzv2h-usb2phy.h headers, driver is now based on regmap.
- Collected PZabel tag.
v7->v8:
- No changes.
v6->v7:
- No changes.
v5->v6:
- No changes.
v4->v5:
- Changed file name to rzv2h-usb-vbenctl.c and Fixed
Makefile, Kconfig, function names accordingly.
- Changed driver .name to "vbenctl" and fix auxiliary_device_id name.
- Updated commit msg.
v3->v4:
- Removed mux_chip->dev.of_node not needed.
v2->v3:
- Added mux_chip->dev.of_node = dev->of_node->child as the mux-controller
is an internal node.
- Fixed auxiliary_device_id name.
- Get rdev using from platform_data.
- Drop struct auxiliary_device adev from reset_rzv2h_usb2phy_adev
as it is needed.
- Drop to_reset_rzv2h_usb2phy_adev() as it is not needed.
v1->v2:
- New patch
drivers/mux/Kconfig | 13 ++++++
drivers/mux/Makefile | 2 +
drivers/mux/rzv2h-vbenctl.c | 81 +++++++++++++++++++++++++++++++++++++
3 files changed, 96 insertions(+)
create mode 100644 drivers/mux/rzv2h-vbenctl.c
diff --git a/drivers/mux/Kconfig b/drivers/mux/Kconfig
index 6d17dfa25dad..eb34457beaab 100644
--- a/drivers/mux/Kconfig
+++ b/drivers/mux/Kconfig
@@ -70,6 +70,19 @@ config MUX_MMIO
To compile the driver as a module, choose M here: the module will
be called mux-mmio.
+config MUX_RZV2H_VBENCTL
+ tristate "Renesas RZ/V2H VBENCTL VBUS_SEL mux driver"
+ depends on RESET_RZV2H_USB2PHY || COMPILE_TEST
+ select REGMAP
+ select AUXILIARY_BUS
+ default RESET_RZV2H_USB2PHY
+ help
+ Support for the VBENCTL VBUS_SEL mux implemented on Renesas
+ RZ/V2H SoCs.
+
+ To compile the driver as a module, choose M here: the module will
+ be called mux-rzv2h-vbenctl.
+
endmenu
endif # MULTIPLEXER
diff --git a/drivers/mux/Makefile b/drivers/mux/Makefile
index 6e9fa47daf56..0854c04613b9 100644
--- a/drivers/mux/Makefile
+++ b/drivers/mux/Makefile
@@ -8,9 +8,11 @@ mux-adg792a-objs := adg792a.o
mux-adgs1408-objs := adgs1408.o
mux-gpio-objs := gpio.o
mux-mmio-objs := mmio.o
+mux-rzv2h-vbenctl-objs := rzv2h-vbenctl.o
obj-$(CONFIG_MULTIPLEXER) += mux-core.o
obj-$(CONFIG_MUX_ADG792A) += mux-adg792a.o
obj-$(CONFIG_MUX_ADGS1408) += mux-adgs1408.o
obj-$(CONFIG_MUX_GPIO) += mux-gpio.o
obj-$(CONFIG_MUX_MMIO) += mux-mmio.o
+obj-$(CONFIG_MUX_RZV2H_VBENCTL) += mux-rzv2h-vbenctl.o
diff --git a/drivers/mux/rzv2h-vbenctl.c b/drivers/mux/rzv2h-vbenctl.c
new file mode 100644
index 000000000000..2699458045f3
--- /dev/null
+++ b/drivers/mux/rzv2h-vbenctl.c
@@ -0,0 +1,81 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Renesas RZ/V2H(P) VBENCTL VBUS_SEL mux driver
+ *
+ * Copyright (C) 2026 Renesas Electronics Corp.
+ */
+
+#include <linux/auxiliary_bus.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/mux/driver.h>
+#include <linux/regmap.h>
+
+#define RZV2H_VBENCTL 0xf0c
+
+struct mux_rzv2h_vbenctl_priv {
+ struct regmap_field *field;
+};
+
+static int mux_rzv2h_vbenctl_set(struct mux_control *mux, int state)
+{
+ struct mux_rzv2h_vbenctl_priv *priv = mux_chip_priv(mux->chip);
+
+ return regmap_field_write(priv->field, state);
+}
+
+static const struct mux_control_ops mux_rzv2h_vbenctl_ops = {
+ .set = mux_rzv2h_vbenctl_set,
+};
+
+static int mux_rzv2h_vbenctl_probe(struct auxiliary_device *adev,
+ const struct auxiliary_device_id *id)
+{
+ const struct reg_field reg_field = REG_FIELD(RZV2H_VBENCTL, 0, 0);
+ struct mux_rzv2h_vbenctl_priv *priv;
+ struct device *dev = &adev->dev;
+ struct mux_chip *mux_chip;
+ struct regmap *regmap;
+ int ret;
+
+ regmap = dev_get_regmap(dev->parent, NULL);
+ if (!regmap)
+ return -ENODEV;
+
+ mux_chip = devm_mux_chip_alloc(dev, 1, sizeof(*priv));
+ if (IS_ERR(mux_chip))
+ return PTR_ERR(mux_chip);
+
+ priv = mux_chip_priv(mux_chip);
+
+ priv->field = devm_regmap_field_alloc(dev, regmap, reg_field);
+ if (IS_ERR(priv->field))
+ return PTR_ERR(priv->field);
+
+ mux_chip->ops = &mux_rzv2h_vbenctl_ops;
+ mux_chip->mux[0].states = 2;
+ mux_chip->mux[0].idle_state = MUX_IDLE_AS_IS;
+
+ ret = devm_mux_chip_register(dev, mux_chip);
+ if (ret < 0)
+ return dev_err_probe(dev, ret, "Failed to register mux chip\n");
+
+ return 0;
+}
+
+static const struct auxiliary_device_id mux_rzv2h_vbenctl_ids[] = {
+ { .name = "rzv2h_usb2phy_reset.vbenctl" },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(auxiliary, mux_rzv2h_vbenctl_ids);
+
+static struct auxiliary_driver mux_rzv2h_vbenctl_driver = {
+ .name = "vbenctl",
+ .probe = mux_rzv2h_vbenctl_probe,
+ .id_table = mux_rzv2h_vbenctl_ids,
+};
+module_auxiliary_driver(mux_rzv2h_vbenctl_driver);
+
+MODULE_DESCRIPTION("RZ/V2H VBENCTL VBUS_SEL mux driver");
+MODULE_AUTHOR("Tommaso Merciai <tommaso.merciai.xr@xxxxxxxxxxxxxx>");
+MODULE_LICENSE("GPL");
--
2.54.0