From d143493c01b7fc3a9b9369a795e20329561222c5 Mon Sep 17 00:00:00 2001 From: Kent Gibson Date: Mon, 28 Sep 2020 08:27:52 +0800 Subject: gpiolib: make cdev a build option Make the gpiolib-cdev module a build option. This allows the CDEV interface to be removed from the kernel to reduce kernel size in applications where is it not required, and provides the parent for other CDEV interface specific build options to follow. Suggested-by: Bartosz Golaszewski Signed-off-by: Kent Gibson Reviewed-by: Andy Shevchenko Signed-off-by: Bartosz Golaszewski --- drivers/gpio/Kconfig | 17 +++++++++++++++-- drivers/gpio/Makefile | 2 +- drivers/gpio/gpiolib-cdev.h | 15 +++++++++++++++ 3 files changed, 31 insertions(+), 3 deletions(-) (limited to 'drivers/gpio') diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig index c7292a50aec4..cbf8a60dec03 100644 --- a/drivers/gpio/Kconfig +++ b/drivers/gpio/Kconfig @@ -66,8 +66,21 @@ config GPIO_SYSFS This ABI is deprecated. If you want to use GPIO from userspace, use the character device /dev/gpiochipN with the appropriate - ioctl() operations instead. The character device is always - available. + ioctl() operations instead. + +config GPIO_CDEV + bool + prompt "Character device (/dev/gpiochipN) support" if EXPERT + default y + help + Say Y here to add the character device /dev/gpiochipN interface + for GPIOs. The character device allows userspace to control GPIOs + using ioctl() operations. + + Only say N if you are sure that the GPIO character device is not + required. + + If unsure, say Y. config GPIO_GENERIC depends on HAS_IOMEM # Only for IOMEM drivers diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile index 639275eb4e4d..6c3791a55a7b 100644 --- a/drivers/gpio/Makefile +++ b/drivers/gpio/Makefile @@ -6,8 +6,8 @@ ccflags-$(CONFIG_DEBUG_GPIO) += -DDEBUG obj-$(CONFIG_GPIOLIB) += gpiolib.o obj-$(CONFIG_GPIOLIB) += gpiolib-devres.o obj-$(CONFIG_GPIOLIB) += gpiolib-legacy.o -obj-$(CONFIG_GPIOLIB) += gpiolib-cdev.o obj-$(CONFIG_OF_GPIO) += gpiolib-of.o +obj-$(CONFIG_GPIO_CDEV) += gpiolib-cdev.o obj-$(CONFIG_GPIO_SYSFS) += gpiolib-sysfs.o obj-$(CONFIG_GPIO_ACPI) += gpiolib-acpi.o diff --git a/drivers/gpio/gpiolib-cdev.h b/drivers/gpio/gpiolib-cdev.h index 973578e7ad10..19a4e3d57120 100644 --- a/drivers/gpio/gpiolib-cdev.h +++ b/drivers/gpio/gpiolib-cdev.h @@ -5,7 +5,22 @@ #include +#ifdef CONFIG_GPIO_CDEV + int gpiolib_cdev_register(struct gpio_device *gdev, dev_t devt); void gpiolib_cdev_unregister(struct gpio_device *gdev); +#else + +static inline int gpiolib_cdev_register(struct gpio_device *gdev, dev_t devt) +{ + return 0; +} + +static inline void gpiolib_cdev_unregister(struct gpio_device *gdev) +{ +} + +#endif /* CONFIG_GPIO_CDEV */ + #endif /* GPIOLIB_CDEV_H */ -- cgit v1.2.3