WSL2-Linux-Kernel/drivers/gpio/Makefile

# gpio support: dedicated expander chips, etc

ccflags-$(CONFIG_DEBUG_GPIO)	+= -DDEBUG

obj-$(CONFIG_HAVE_GPIO_LIB)	+= gpiolib.o
gpiolib: add drivers/gpio directory Add an empty drivers/gpio directory for gpiolib infrastructure and GPIO expanders. It will be populated by later patches. This won't be the only place to hold such gpio_chip code. Many external chips add a few GPIOs as secondary functionality (such as MFD drivers) and platform code frequently needs to closely integrate GPIO and IRQ support. This is placed early in the build/link sequence since it's common for other drivers to depend on GPIOs to do their work, so they must be initialized early in the device_initcall() sequence. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Acked-by: Jean Delvare <khali@linux-fr.org> Cc: Eric Miao <eric.miao@marvell.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Haavard Skinnemoen <hskinnemoen@atmel.com> Cc: Philipp Zabel <philipp.zabel@gmail.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ben Gardner <bgardner@wabtec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 2008-02-05 09:28:17 +03:00			`# gpio support: dedicated expander chips, etc`

			`ccflags-$(CONFIG_DEBUG_GPIO) += -DDEBUG`

gpiolib: add gpio provider infrastructure Provide new implementation infrastructure that platforms may choose to use when implementing the GPIO programming interface. Platforms can update their GPIO support to use this. In many cases the incremental cost to access a non-inlined GPIO should be less than a dozen instructions, with the memory cost being about a page (total) of extra data and code. The upside is: * Providing two features which were "want to have (but OK to defer)" when GPIO interfaces were first discussed in November 2006: - A "struct gpio_chip" to plug in GPIOs that aren't directly supported by SOC platforms, but come from FPGAs or other multifunction devices using conventional device registers (like UCB-1x00 or SM501 GPIOs, and southbridges in PCs with more open specs than usual). - Full support for message-based GPIO expanders, where registers are accessed through sleeping I/O calls. Previous support for these "cansleep" calls was just stubs. (One example: the widely used pcf8574 I2C chips, with 8 GPIOs each.) * Including a non-stub implementation of the gpio_{request,free}() calls, making those calls much more useful. The diagnostic labels are also recorded given DEBUG_FS, so /sys/kernel/debug/gpio can show a snapshot of all GPIOs known to this infrastructure. The driver programming interfaces introduced in 2.6.21 do not change at all; this infrastructure is entirely below those covers. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Jean Delvare <khali@linux-fr.org> Cc: Eric Miao <eric.miao@marvell.com> Cc: Haavard Skinnemoen <hskinnemoen@atmel.com> Cc: Philipp Zabel <philipp.zabel@gmail.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ben Gardner <bgardner@wabtec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 2008-02-05 09:28:20 +03:00			`obj-$(CONFIG_HAVE_GPIO_LIB) += gpiolib.o`