gpio: Add Intel USBIO GPIO driver

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.

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Co-developed-by: Hans de Goede <hansg@kernel.org>
Signed-off-by: Hans de Goede <hansg@kernel.org>
Signed-off-by: Israel Cepeda <israel.a.cepeda.lopez@intel.com>
Link: https://lore.kernel.org/r/20250911181343.77398-3-hansg@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/MAINTAINERS b/MAINTAINERS
index 434ac1593332aeb0dc783ef1f7f5ba18f2089238..7fef488118a46d2303f885960495d8dc7888021d 100644 (file)
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -12693,6 +12693,7 @@ M:      Israel Cepeda <israel.a.cepeda.lopez@intel.com>
 M:     Hans de Goede <hansg@kernel.org>
 R:     Sakari Ailus <sakari.ailus@linux.intel.com>
 S:     Maintained
+F:     drivers/gpio/gpio-usbio.c
 F:     drivers/usb/misc/usbio.c
 F:     include/linux/usb/usbio.h
 

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index e43abb322fa6e15f19f2f498aa5adea03e6cd3bf..9390ef4e507987e5fb94e7169eddef31a09e37d8 100644 (file)
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -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"

diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 379f55e9ed1e69cd9c5745f8643541b85953db1c..b1593ce92ebe7b10b41c71f4516e7789bda543f9 100644 (file)
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -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

diff --git a/drivers/gpio/gpio-usbio.c b/drivers/gpio/gpio-usbio.c
new file mode 100644 (file)
index 0000000..e13c120
--- /dev/null
+++ b/drivers/gpio/gpio-usbio.c
@@ -0,0 +1,247 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2025 Intel Corporation.
+ * Copyright (c) 2025 Red Hat, Inc.
+ */
+
+#include <linux/acpi.h>
+#include <linux/auxiliary_bus.h>
+#include <linux/cleanup.h>
+#include <linux/device.h>
+#include <linux/gpio/driver.h>
+#include <linux/mutex.h>
+#include <linux/types.h>
+#include <linux/usb/usbio.h>
+
+struct usbio_gpio_bank {
+       u8 config[USBIO_GPIOSPERBANK];
+       u32 bitmap;
+};
+
+struct usbio_gpio {
+       struct mutex config_mutex; /* Protects banks[x].config */
+       struct usbio_gpio_bank banks[USBIO_MAX_GPIOBANKS];
+       struct gpio_chip gc;
+       struct auxiliary_device *adev;
+};
+
+static const struct acpi_device_id usbio_gpio_acpi_hids[] = {
+       { "INTC1007" }, /* MTL */
+       { "INTC10B2" }, /* ARL */
+       { "INTC10B5" }, /* LNL */
+       { "INTC10E2" }, /* PTL */
+       { }
+};
+
+static void usbio_gpio_get_bank_and_pin(struct gpio_chip *gc, unsigned int offset,
+                                       struct usbio_gpio_bank **bank_ret,
+                                       unsigned int *pin_ret)
+{
+       struct usbio_gpio *gpio = gpiochip_get_data(gc);
+       struct device *dev = &gpio->adev->dev;
+       struct usbio_gpio_bank *bank;
+       unsigned int pin;
+
+       bank = &gpio->banks[offset / USBIO_GPIOSPERBANK];
+       pin = offset % USBIO_GPIOSPERBANK;
+       if (~bank->bitmap & BIT(pin)) {
+               /* The FW bitmap sometimes is invalid, warn and continue */
+               dev_warn_once(dev, FW_BUG "GPIO %u is not in FW pins bitmap\n", offset);
+       }
+
+       *bank_ret = bank;
+       *pin_ret = pin;
+}
+
+static int usbio_gpio_get_direction(struct gpio_chip *gc, unsigned int offset)
+{
+       struct usbio_gpio_bank *bank;
+       unsigned int pin;
+       u8 cfg;
+
+       usbio_gpio_get_bank_and_pin(gc, offset, &bank, &pin);
+
+       cfg = bank->config[pin] & USBIO_GPIO_PINMOD_MASK;
+
+       return (cfg == USBIO_GPIO_PINMOD_OUTPUT) ?
+               GPIO_LINE_DIRECTION_OUT : GPIO_LINE_DIRECTION_IN;
+}
+
+static int usbio_gpio_get(struct gpio_chip *gc, unsigned int offset)
+{
+       struct usbio_gpio *gpio = gpiochip_get_data(gc);
+       struct usbio_gpio_bank *bank;
+       struct usbio_gpio_rw gbuf;
+       unsigned int pin;
+       int ret;
+
+       usbio_gpio_get_bank_and_pin(gc, offset, &bank, &pin);
+
+       gbuf.bankid = offset / USBIO_GPIOSPERBANK;
+       gbuf.pincount  = 1;
+       gbuf.pin = pin;
+
+       ret = usbio_control_msg(gpio->adev, USBIO_PKTTYPE_GPIO, USBIO_GPIOCMD_READ,
+                               &gbuf, sizeof(gbuf) - sizeof(gbuf.value),
+                               &gbuf, sizeof(gbuf));
+       if (ret != sizeof(gbuf))
+               return (ret < 0) ? ret : -EPROTO;
+
+       return (le32_to_cpu(gbuf.value) >> pin) & 1;
+}
+
+static int usbio_gpio_set(struct gpio_chip *gc, unsigned int offset, int value)
+{
+       struct usbio_gpio *gpio = gpiochip_get_data(gc);
+       struct usbio_gpio_bank *bank;
+       struct usbio_gpio_rw gbuf;
+       unsigned int pin;
+
+       usbio_gpio_get_bank_and_pin(gc, offset, &bank, &pin);
+
+       gbuf.bankid = offset / USBIO_GPIOSPERBANK;
+       gbuf.pincount  = 1;
+       gbuf.pin = pin;
+       gbuf.value = cpu_to_le32(value << pin);
+
+       return usbio_control_msg(gpio->adev, USBIO_PKTTYPE_GPIO, USBIO_GPIOCMD_WRITE,
+                                &gbuf, sizeof(gbuf), NULL, 0);
+}
+
+static int usbio_gpio_update_config(struct gpio_chip *gc, unsigned int offset,
+                                   u8 mask, u8 value)
+{
+       struct usbio_gpio *gpio = gpiochip_get_data(gc);
+       struct usbio_gpio_bank *bank;
+       struct usbio_gpio_init gbuf;
+       unsigned int pin;
+
+       usbio_gpio_get_bank_and_pin(gc, offset, &bank, &pin);
+
+       guard(mutex)(&gpio->config_mutex);
+
+       bank->config[pin] &= ~mask;
+       bank->config[pin] |= value;
+
+       gbuf.bankid = offset / USBIO_GPIOSPERBANK;
+       gbuf.config = bank->config[pin];
+       gbuf.pincount  = 1;
+       gbuf.pin = pin;
+
+       return usbio_control_msg(gpio->adev, USBIO_PKTTYPE_GPIO, USBIO_GPIOCMD_INIT,
+                                &gbuf, sizeof(gbuf), NULL, 0);
+}
+
+static int usbio_gpio_direction_input(struct gpio_chip *gc, unsigned int offset)
+{
+       return usbio_gpio_update_config(gc, offset, USBIO_GPIO_PINMOD_MASK,
+                                       USBIO_GPIO_SET_PINMOD(USBIO_GPIO_PINMOD_INPUT));
+}
+
+static int usbio_gpio_direction_output(struct gpio_chip *gc,
+               unsigned int offset, int value)
+{
+       int ret;
+
+       ret = usbio_gpio_update_config(gc, offset, USBIO_GPIO_PINMOD_MASK,
+                                      USBIO_GPIO_SET_PINMOD(USBIO_GPIO_PINMOD_OUTPUT));
+       if (ret)
+               return ret;
+
+       return usbio_gpio_set(gc, offset, value);
+}
+
+static int usbio_gpio_set_config(struct gpio_chip *gc, unsigned int offset,
+               unsigned long config)
+{
+       u8 value;
+
+       switch (pinconf_to_config_param(config)) {
+       case PIN_CONFIG_BIAS_PULL_PIN_DEFAULT:
+               value = USBIO_GPIO_SET_PINCFG(USBIO_GPIO_PINCFG_DEFAULT);
+               break;
+       case PIN_CONFIG_BIAS_PULL_UP:
+               value = USBIO_GPIO_SET_PINCFG(USBIO_GPIO_PINCFG_PULLUP);
+               break;
+       case PIN_CONFIG_BIAS_PULL_DOWN:
+               value = USBIO_GPIO_SET_PINCFG(USBIO_GPIO_PINCFG_PULLDOWN);
+               break;
+       case PIN_CONFIG_DRIVE_PUSH_PULL:
+               value = USBIO_GPIO_SET_PINCFG(USBIO_GPIO_PINCFG_PUSHPULL);
+               break;
+       default:
+               return -ENOTSUPP;
+       }
+
+       return usbio_gpio_update_config(gc, offset, USBIO_GPIO_PINCFG_MASK, value);
+}
+
+static int usbio_gpio_probe(struct auxiliary_device *adev,
+               const struct auxiliary_device_id *adev_id)
+{
+       struct usbio_gpio_bank_desc *bank_desc;
+       struct device *dev = &adev->dev;
+       struct usbio_gpio *gpio;
+       int bank, ret;
+
+       bank_desc = dev_get_platdata(dev);
+       if (!bank_desc)
+               return -EINVAL;
+
+       gpio = devm_kzalloc(dev, sizeof(*gpio), GFP_KERNEL);
+       if (!gpio)
+               return -ENOMEM;
+
+       ret = devm_mutex_init(dev, &gpio->config_mutex);
+       if (ret)
+               return ret;
+
+       gpio->adev = adev;
+
+       usbio_acpi_bind(gpio->adev, usbio_gpio_acpi_hids);
+
+       for (bank = 0; bank < USBIO_MAX_GPIOBANKS && bank_desc[bank].bmap; bank++)
+               gpio->banks[bank].bitmap = le32_to_cpu(bank_desc[bank].bmap);
+
+       gpio->gc.label = ACPI_COMPANION(dev) ?
+                                       acpi_dev_name(ACPI_COMPANION(dev)) : dev_name(dev);
+       gpio->gc.parent = dev;
+       gpio->gc.owner = THIS_MODULE;
+       gpio->gc.get_direction = usbio_gpio_get_direction;
+       gpio->gc.direction_input = usbio_gpio_direction_input;
+       gpio->gc.direction_output = usbio_gpio_direction_output;
+       gpio->gc.get = usbio_gpio_get;
+       gpio->gc.set = usbio_gpio_set;
+       gpio->gc.set_config = usbio_gpio_set_config;
+       gpio->gc.base = -1;
+       gpio->gc.ngpio = bank * USBIO_GPIOSPERBANK;
+       gpio->gc.can_sleep = true;
+
+       ret = devm_gpiochip_add_data(dev, &gpio->gc, gpio);
+       if (ret)
+               return ret;
+
+       if (has_acpi_companion(dev))
+               acpi_dev_clear_dependencies(ACPI_COMPANION(dev));
+
+       return 0;
+}
+
+static const struct auxiliary_device_id usbio_gpio_id_table[] = {
+       { "usbio.usbio-gpio" },
+       { }
+};
+MODULE_DEVICE_TABLE(auxiliary, usbio_gpio_id_table);
+
+static struct auxiliary_driver usbio_gpio_driver = {
+       .name = USBIO_GPIO_CLIENT,
+       .probe = usbio_gpio_probe,
+       .id_table = usbio_gpio_id_table
+};
+module_auxiliary_driver(usbio_gpio_driver);
+
+MODULE_DESCRIPTION("Intel USBIO GPIO driver");
+MODULE_AUTHOR("Israel Cepeda <israel.a.cepeda.lopez@intel.com>");
+MODULE_AUTHOR("Hans de Goede <hansg@kernel.org>");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS("USBIO");