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usb/gpio/i2c: Add Intel USBIO USB IO-expander drivers

PATCH In review Hans de Goede 4 participants 9 messages Sep 11, 2025 – Sep 12, 2025

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Hans de Goede

author maintainer
#0 lore raw

v6 cover usb/gpio/i2c: Add Intel USBIO USB IO-expander drivers

Hi All,

Here is v6 of the patch series to add support for the Intel USBIO USB IO-expander used by the MIPI cameras on various new (Meteor Lake and later) Intel laptops.

Changes in v6:
- Drop I2C_FUNC_10BIT_ADDR from advertised I2C functionality
- Add Bart's Acked-by to the GPIO driver

Changes in v5:
- GPIO: Move GPIO_USBIO Kconfig option under 'menu "USB GPIO expanders"'
- I2C: Drop some unnecessary dev_dbg() messages
- I2C: Add I2C_AQ_NO_ZERO_LEN to the adapter quirks

Changes in v4:
- GPIO: Drop include <linux/dev_printk.h>, unneeded auxiliary_set_drvdata()

Changes in v3:
- Drop (offset >= gc->ngpio) check and make usbio_gpio_get_bank_and_pin() return void
- Propagate usbio_gpio_set() ret val in usbio_gpio_direction_output()
- Use devm_gpiochip_add_data() and drop auxiliary_driver remove() callback

Changes in v2:
- Split usbio-bridge mutex into ctrl_mutex and bulk_mutex
- Drop SPI support since this is not used on devices in the field
- Rework disconnect handling to be more robust
- Several different revisions need special casing add a quirks mechanism for this
- Stop using stdint.h (uintX_t) types
- Use __le16, __le32 type + cpu_to_le16() and friends for on wire words
- Properly check auxiliary_device_add() return value
- Add a mutex to the GPIO driver to protect usbio_gpio_update_config() calls, which read-modify-write banks[x].config, racing with each other
- Adjust usbio_gpio_get() to have an int return value and propagate the usbio_control_msg() return value
- Various (small) style fixes from Sakari's review of all 3 patches

The first patch adds an USB bridge driver which registers auxbus children for the GPIO and I2C functions of the USBIO chip.

The second and third patch add a GPIO resp. an I2C driver for the auxbus children using the IO functions exported by the USB bridge driver.

The second and third patch depend on the IO functions exported by the first patch. So to merge this we will need either an immutable tag on the USB tree.

Regards,

Hans

Israel Cepeda (3):
usb: misc: Add Intel USBIO bridge driver
gpio: Add Intel USBIO GPIO driver
i2c: Add Intel USBIO I2C driver

 MAINTAINERS                    |  10 +
 drivers/gpio/Kconfig           |  11 +
 drivers/gpio/Makefile          |   1 +
 drivers/gpio/gpio-usbio.c      | 247 +++++++++++
 drivers/i2c/busses/Kconfig     |  11 +
 drivers/i2c/busses/Makefile    |   1 +
 drivers/i2c/busses/i2c-usbio.c | 320 ++++++++++++++
 drivers/usb/misc/Kconfig       |  14 +
 drivers/usb/misc/Makefile      |   1 +
 drivers/usb/misc/usbio.c       | 749 +++++++++++++++++++++++++++++++++
 include/linux/usb/usbio.h      | 177 ++++++++
 11 files changed, 1542 insertions(+)
 create mode 100644 drivers/gpio/gpio-usbio.c
 create mode 100644 drivers/i2c/busses/i2c-usbio.c
 create mode 100644 drivers/usb/misc/usbio.c
 create mode 100644 include/linux/usb/usbio.h
Signature · 1 line
2.51.0
author maintainer
#1 lore raw

PATCH v6 1/3 usb: misc: Add Intel USBIO bridge driver

From: Israel Cepeda <[email protected]>

Add a driver for the Intel USBIO USB IO-expander used by the MIPI cameras on various new (Meteor Lake and later) Intel laptops.

This is an USB bridge driver which adds auxbus child devices for the GPIO, I2C and SPI functions of the USBIO chip and which exports IO-functions for the drivers for the auxbus child devices to communicate with the USBIO device's firmware.

---
Changes in v2:
- Split usbio-bridge mutex into ctrl_mutex and bulk_mutex
- Drop SPI support since this is not used on devices in the field
- Rework disconnect handling to be more robust
- Several different revisions need special casing add a quirks mechanism for this
- Stop using stdint.h (uintX_t) types
- Use __le16, __le32 type + cpu_to_le16() and friends for on wire words
- Properly check auxiliary_device_add() return value
- Some small style fixes from Sakari's review

---
 MAINTAINERS               |   8 +
 drivers/usb/misc/Kconfig  |  14 +
 drivers/usb/misc/Makefile |   1 +
 drivers/usb/misc/usbio.c  | 749 ++++++++++++++++++++++++++++++++++++++
 include/linux/usb/usbio.h | 177 +++++++++
 5 files changed, 949 insertions(+)
 create mode 100644 drivers/usb/misc/usbio.c
 create mode 100644 include/linux/usb/usbio.h
MAINTAINERS +8 -0
index 42debb2dc76a..72689972d669 100644
@@ -12694,6 +12694,14 @@ S:	Maintained
 F:	Documentation/admin-guide/pm/intel_uncore_frequency_scaling.rst
 F:	drivers/platform/x86/intel/uncore-frequency/
 
+INTEL USBIO USB I/O EXPANDER DRIVERS
+M:	Israel Cepeda <[email protected]>
+M:	Hans de Goede <[email protected]>
+R:	Sakari Ailus <[email protected]>
+S:	Maintained
+F:	drivers/usb/misc/usbio.c
+F:	include/linux/usb/usbio.h
+
 INTEL VENDOR SPECIFIC EXTENDED CAPABILITIES DRIVER
 M:	David E. Box <[email protected]>
 S:	Supported
drivers/usb/misc/Kconfig +14 -0
index 6497c4e81e95..bfe08e15d051 100644
@@ -178,6 +178,20 @@ config USB_LJCA
 	  This driver can also be built as a module. If so, the module
 	  will be called usb-ljca.
 
+config USB_USBIO
+	tristate "Intel USBIO Bridge support"
+	depends on USB && ACPI
+	select AUXILIARY_BUS
+	help
+	  This adds support for Intel USBIO drivers.
+	  This enables the USBIO bridge driver module in charge to talk
+	  to the USB device. Additional drivers such as GPIO_USBIO and
+	  I2C_USBIO must be enabled in order to use the device's full
+	  functionality.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called usbio.
+
 source "drivers/usb/misc/sisusbvga/Kconfig"
 
 config USB_LD
drivers/usb/misc/Makefile +1 -0
index 0cd5bc8f52fe..494ab0377f35 100644
@@ -12,6 +12,7 @@ obj-$(CONFIG_USB_EMI62)			+= emi62.o
 obj-$(CONFIG_USB_EZUSB_FX2)		+= ezusb.o
 obj-$(CONFIG_APPLE_MFI_FASTCHARGE)	+= apple-mfi-fastcharge.o
 obj-$(CONFIG_USB_LJCA)			+= usb-ljca.o
+obj-$(CONFIG_USB_USBIO)			+= usbio.o
 obj-$(CONFIG_USB_IDMOUSE)		+= idmouse.o
 obj-$(CONFIG_USB_IOWARRIOR)		+= iowarrior.o
 obj-$(CONFIG_USB_ISIGHTFW)		+= isight_firmware.o
drivers/usb/misc/usbio.c new file +749 -0

749 lines not on this page · raw message

include/linux/usb/usbio.h new file +177 -0

177 lines not on this page · raw message

Signature · 1 line
2.51.0
author maintainer
#2 lore raw

PATCH v6 2/3 gpio: Add Intel USBIO GPIO driver

In reply to Hans de Goede

From: Israel Cepeda <[email protected]>

Add a a driver for the GPIO auxbus child device of the Intel USBIO USB IO-expander used by the MIPI cameras on various new (Meteor Lake and later) Intel laptops.

---
Changes in v5:
- Move GPIO_USBIO Kconfig option under 'menu "USB GPIO expanders"'

Changes in v4:
- Drop include <linux/dev_printk.h>, unneeded auxiliary_set_drvdata()

Changes in v3:
- Drop (offset >= gc->ngpio) check and make usbio_gpio_get_bank_and_pin() return void
- Propagate usbio_gpio_set() ret val in usbio_gpio_direction_output()
- Use devm_gpiochip_add_data() and drop auxiliary_driver remove() callback

Changes in v2:
- Add a config_mutex protect usbio_gpio_update_config() calls, which read-modify-write banks[x].config, racing with each other
- Adjust usbio_gpio_get() to have an int return value and propagate the usbio_control_msg() return value
- Use __le16, __le32 type + cpu_to_le16() and friends for on wire words
- Some small style fixes from Sakari's review

---
 MAINTAINERS               |   1 +
 drivers/gpio/Kconfig      |  11 ++
 drivers/gpio/Makefile     |   1 +
 drivers/gpio/gpio-usbio.c | 247 ++++++++++++++++++++++++++++++++++++++
 4 files changed, 260 insertions(+)
 create mode 100644 drivers/gpio/gpio-usbio.c
MAINTAINERS +1 -0
index 72689972d669..8189bd88dd7e 100644
@@ -12699,6 +12699,7 @@ M:	Israel Cepeda <[email protected]>
 M:	Hans de Goede <[email protected]>
 R:	Sakari Ailus <[email protected]>
 S:	Maintained
+F:	drivers/gpio/gpio-usbio.c
 F:	drivers/usb/misc/usbio.c
 F:	include/linux/usb/usbio.h
 
drivers/gpio/Kconfig +11 -0
index d8ac40d0eb6f..efd72c72ad40 100644
@@ -1923,6 +1923,17 @@ config GPIO_MPSSE
 	  GPIO driver for FTDI's MPSSE interface. These can do input and
 	  output. Each MPSSE provides 16 IO pins.
 
+config GPIO_USBIO
+	tristate "Intel USBIO GPIO support"
+	depends on USB_USBIO
+	default USB_USBIO
+	help
+	  Select this option to enable GPIO driver for the INTEL
+	  USBIO driver stack.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called gpio_usbio.
+
 endmenu
 
 menu "Virtual GPIO drivers"
drivers/gpio/Makefile +1 -0
index 379f55e9ed1e..b1593ce92ebe 100644
@@ -192,6 +192,7 @@ obj-$(CONFIG_GPIO_TS5500)		+= gpio-ts5500.o
 obj-$(CONFIG_GPIO_TWL4030)		+= gpio-twl4030.o
 obj-$(CONFIG_GPIO_TWL6040)		+= gpio-twl6040.o
 obj-$(CONFIG_GPIO_UNIPHIER)		+= gpio-uniphier.o
+obj-$(CONFIG_GPIO_USBIO) 		+= gpio-usbio.o
 obj-$(CONFIG_GPIO_VF610)		+= gpio-vf610.o
 obj-$(CONFIG_GPIO_VIPERBOARD)		+= gpio-viperboard.o
 obj-$(CONFIG_GPIO_VIRTUSER)		+= gpio-virtuser.o
drivers/gpio/gpio-usbio.c new file +247 -0

247 lines not on this page · raw message

Signature · 1 line
2.51.0
author maintainer
#3 lore raw

PATCH v6 3/3 i2c: Add Intel USBIO I2C driver

In reply to Hans de Goede

From: Israel Cepeda <[email protected]>

Add a a driver for the I2C auxbus child device of the Intel USBIO USB IO-expander used by the MIPI cameras on various new (Meteor Lake and later) Intel laptops.

---
Changes in v6:
- Drop I2C_FUNC_10BIT_ADDR from advertised functionality

Changes in v5:
- Drop some unnecessary dev_dbg() messages
- Add I2C_AQ_NO_ZERO_LEN to the adapter quirks

Changes in v2:
- Use new quirks mechanism to treat various revisions differently
- Use __le16, __le32 type + cpu_to_le16() and friends for on wire words
- Some small style fixes from Sakari's review

---
 MAINTAINERS                    |   1 +
 drivers/i2c/busses/Kconfig     |  11 ++
 drivers/i2c/busses/Makefile    |   1 +
 drivers/i2c/busses/i2c-usbio.c | 320 +++++++++++++++++++++++++++++++++
 4 files changed, 333 insertions(+)
 create mode 100644 drivers/i2c/busses/i2c-usbio.c
MAINTAINERS +1 -0
index 8189bd88dd7e..6a6f55516597 100644
@@ -12700,6 +12700,7 @@ M:	Hans de Goede <[email protected]>
 R:	Sakari Ailus <[email protected]>
 S:	Maintained
 F:	drivers/gpio/gpio-usbio.c
+F:	drivers/i2c/busses/i2c-usbio.c
 F:	drivers/usb/misc/usbio.c
 F:	include/linux/usb/usbio.h
 
drivers/i2c/busses/Kconfig +11 -0
index 070d014fdc5d..06b1b702fd7a 100644
@@ -1357,6 +1357,17 @@ config I2C_LJCA
 	  This driver can also be built as a module.  If so, the module
 	  will be called i2c-ljca.
 
+config I2C_USBIO
+	tristate "Intel USBIO I2C Adapter support"
+	depends on USB_USBIO
+	default USB_USBIO
+	help
+	  Select this option to enable I2C driver for the INTEL
+	  USBIO driver stack.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called i2c_usbio.
+
 config I2C_CP2615
 	tristate "Silicon Labs CP2615 USB sound card and I2C adapter"
 	depends on USB
drivers/i2c/busses/Makefile +1 -0
index 04db855fdfd6..401a79c9767e 100644
@@ -135,6 +135,7 @@ obj-$(CONFIG_I2C_GXP)		+= i2c-gxp.o
 obj-$(CONFIG_I2C_DIOLAN_U2C)	+= i2c-diolan-u2c.o
 obj-$(CONFIG_I2C_DLN2)		+= i2c-dln2.o
 obj-$(CONFIG_I2C_LJCA)		+= i2c-ljca.o
+obj-$(CONFIG_I2C_USBIO)		+= i2c-usbio.o
 obj-$(CONFIG_I2C_CP2615) += i2c-cp2615.o
 obj-$(CONFIG_I2C_PARPORT)	+= i2c-parport.o
 obj-$(CONFIG_I2C_PCI1XXXX)	+= i2c-mchp-pci1xxxx.o
drivers/i2c/busses/i2c-usbio.c new file +320 -0

320 lines not on this page · raw message

Signature · 1 line
2.51.0
Reviewed-by on v6 3/3
#4 lore raw

Re: [PATCH v6 3/3] i2c: Add Intel USBIO I2C driver

Quoted 9 lines · Hans de Goede

From: Israel Cepeda <[email protected]>

Add a a driver for the I2C auxbus child device of the Intel USBIO USB IO-expander used by the MIPI cameras on various new (Meteor Lake and later) Intel laptops.

author maintainer
#5 lore raw

Re: [PATCH v6 3/3] i2c: Add Intel USBIO I2C driver

Hi Wolfram,

Quoted 7 lines · Wolfram Sang
Quoted 6 lines · Hans de Goede

From: Israel Cepeda <[email protected]>

Add a a driver for the I2C auxbus child device of the Intel USBIO USB IO-expander used by the MIPI cameras on various new (Meteor Lake and later) Intel laptops.

Quoted 5 lines
Quoted 3 lines

Thank you.

Is it ok if Greg picks this up together with the rest of the series?

Regards,

Hans

#7 lore raw

Re: [PATCH v6 3/3] i2c: Add Intel USBIO I2C driver

Quoted 9 lines · Wolfram Sang
Quoted 7 lines
Quoted 2 lines

Thank you.

Is it ok if Greg picks this up together with the rest of the series?

Yes.

Great, I'll go queue it up in a bit, thanks!

greg k-h

reviewer Reviewed-by on the v6 series
#8 lore raw
In reply to Hans de Goede

Hi Hans,

Quoted 5 lines · Hans de Goede

Hi All,

Here is v6 of the patch series to add support for the Intel USBIO USB IO-expander used by the MIPI cameras on various new (Meteor Lake and later) Intel laptops.

For the set:

Signature · 3 lines
Kind regards,

Sakari Ailus