| Message ID | 20200623040107.22270-15-warthog618@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | gpio: cdev: add uAPI V2 | expand |
On Tue, Jun 23, 2020 at 6:02 AM Kent Gibson <warthog618@gmail.com> wrote: > > 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 other CDEV interface specific build options to follow. > > Suggested-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> > Signed-off-by: Kent Gibson <warthog618@gmail.com> > > --- > drivers/gpio/Kconfig | 16 ++++++++++++++-- > drivers/gpio/Makefile | 2 +- > drivers/gpio/gpiolib-cdev.h | 15 +++++++++++++++ > 3 files changed, 30 insertions(+), 3 deletions(-) > > diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig > index c6b5c65c8405..affc1524bc2c 100644 > --- a/drivers/gpio/Kconfig > +++ b/drivers/gpio/Kconfig > @@ -66,8 +66,20 @@ 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 "/dev/gpiochipN (character device interface)" > + 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 is 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 ef666cfef9d0..45eb09808d12 100644 > --- a/drivers/gpio/Makefile > +++ b/drivers/gpio/Makefile > @@ -7,8 +7,8 @@ obj-$(CONFIG_GPIOLIB) += gpiolib.o > obj-$(CONFIG_GPIOLIB) += gpiolib-devres.o > obj-$(CONFIG_GPIOLIB) += gpiolib-legacy.o > obj-$(CONFIG_GPIOLIB) += gpiolib-devprop.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-$(CONFIG_GPIO_ACPI) += gpiolib-acpi.o > > diff --git a/drivers/gpio/gpiolib-cdev.h b/drivers/gpio/gpiolib-cdev.h > index 973578e7ad10..19a4e3d57120 100644 > --- a/drivers/gpio/gpiolib-cdev.h > +++ b/drivers/gpio/gpiolib-cdev.h > @@ -5,7 +5,22 @@ > > #include <linux/device.h> > > +#ifdef CONFIG_GPIO_CDEV > + > int gpiolib_cdev_register(struct gpio_device *gdev, dev_t devt); > void gpiolib_cdev_unregister(struct gpio_device *gdev); > > +#else > + > +static inline int gpiolib_cdev_register(struct gpio_device *gdev, dev_t devt) > +{ > + return 0; > +} > + > +static inline void gpiolib_cdev_unregister(struct gpio_device *gdev) > +{ > +} > + > +#endif /* CONFIG_GPIO_CDEV */ > + > #endif /* GPIOLIB_CDEV_H */ > -- > 2.27.0 > I know Linus doesn't like this, but I'm personally in favor of adding this as long as it's enabled by default. Reviewed-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig index c6b5c65c8405..affc1524bc2c 100644 --- a/drivers/gpio/Kconfig +++ b/drivers/gpio/Kconfig @@ -66,8 +66,20 @@ config GPIO_SYSFS This ABI is deprecated. If you want to use GPIO from userspace, use the character device /dev/gpiochipN with the appropriate - ioctl() operations instead. The character device is always - available. + ioctl() operations instead. + +config GPIO_CDEV + bool "/dev/gpiochipN (character device interface)" + default y + help + Say Y here to add the character device /dev/gpiochipN interface + for GPIOs. The character device allows userspace to control GPIOs + using ioctl() operations. + + Only say N is you are sure that the GPIO character device is not + required. + + If unsure, say Y. config GPIO_GENERIC depends on HAS_IOMEM # Only for IOMEM drivers diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile index ef666cfef9d0..45eb09808d12 100644 --- a/drivers/gpio/Makefile +++ b/drivers/gpio/Makefile @@ -7,8 +7,8 @@ obj-$(CONFIG_GPIOLIB) += gpiolib.o obj-$(CONFIG_GPIOLIB) += gpiolib-devres.o obj-$(CONFIG_GPIOLIB) += gpiolib-legacy.o obj-$(CONFIG_GPIOLIB) += gpiolib-devprop.o -obj-$(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 <linux/device.h> +#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 */
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 other CDEV interface specific build options to follow. Suggested-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> Signed-off-by: Kent Gibson <warthog618@gmail.com> --- drivers/gpio/Kconfig | 16 ++++++++++++++-- drivers/gpio/Makefile | 2 +- drivers/gpio/gpiolib-cdev.h | 15 +++++++++++++++ 3 files changed, 30 insertions(+), 3 deletions(-)