gpiolib: Allow user-selection
Subsystems (10)
PATCH v2 1/1 gpiolib: Allow user-selection
This patch adds functionality to the gpio-lib subsystem to make it possible to enable the gpio-lib code even if the architecture code didn't request to get it built in.
The archtitecture code does still need to implement the gpiolib accessor functions in its asm/gpio.h file.
This patch adds the implementations for x86 and PPC.
With these changes it is possible to run generic GPIO expansion cards on every architecture that implements the trivial wrapper functions. Support for more architectures can easily be added.
---
This patch should be scheduled for the next kernel feature merge window. This is diffed against current linux-next. Compiletested on x86 and powerpc. Runtime tested on x86.
arch/x86/Kconfig +1 -0
@@ -27,6 +27,7 @@ select HAVE_FTRACE select HAVE_KVM if ((X86_32 && !X86_VOYAGER && !X86_VISWS && !X86_NUMAQ) || X86_64) select HAVE_ARCH_KGDB if !X86_VOYAGER + select ARCH_WANT_OPTIONAL_GPIOLIB if !X86_RDC321X config ARCH_DEFCONFIG string
include/asm-x86/gpio.h +56 -0
62 lines not on this page · raw message
arch/powerpc/Kconfig +1 -0
@@ -113,6 +113,7 @@ select HAVE_LMB select USE_GENERIC_SMP_HELPERS if SMP select HAVE_OPROFILE + select ARCH_WANT_OPTIONAL_GPIOLIB config EARLY_PRINTK bool
drivers/gpio/Kconfig +29 -4
@@ -2,15 +2,40 @@ # GPIO infrastructure and expanders # -config HAVE_GPIO_LIB +config ARCH_WANT_OPTIONAL_GPIOLIB bool help + Select this config option from the architecture Kconfig, if + it is possible to use gpiolib on the architecture, but let the + user decide whether to actually build it or not. + Select this instead of ARCH_REQUIRE_GPIOLIB, if your architecture does + not depend on GPIOs being available, but rather let the user + decide whether he needs it or not. + +config ARCH_REQUIRE_GPIOLIB + bool + select GPIOLIB + help Platforms select gpiolib if they use this infrastructure for all their GPIOs, usually starting with ones integrated into SOC processors. + Selecting this from the architecture code will cause the gpiolib + code to always get built in. + + + +menuconfig GPIOLIB + bool "GPIO Support" + depends on ARCH_WANT_OPTIONAL_GPIOLIB || ARCH_REQUIRE_GPIOLIB + select GENERIC_GPIO + help + This enables GPIO support through the generic GPIO library. + You only need to enable this, if you also want to enable + one or more of the GPIO expansion card drivers below. + + If unsure, say N. -menu "GPIO Support" - depends on HAVE_GPIO_LIB +if GPIOLIB config DEBUG_GPIO bool "Debug GPIO calls"
@@ -70,4 +95,4 @@ SPI driver for Microchip MCP23S08 I/O expander. This provides a GPIO interface supporting inputs and outputs. -endmenu +endif
drivers/gpio/Makefile +1 -1
@@ -2,7 +2,7 @@ ccflags-$(CONFIG_DEBUG_GPIO) += -DDEBUG -obj-$(CONFIG_HAVE_GPIO_LIB) += gpiolib.o +obj-$(CONFIG_GPIOLIB) += gpiolib.o obj-$(CONFIG_GPIO_MCP23S08) += mcp23s08.o obj-$(CONFIG_GPIO_PCA953X) += pca953x.o
Documentation/gpio.txt +11 -1
@@ -392,11 +392,21 @@ Platform Support ---------------- -To support this framework, a platform's Kconfig will "select HAVE_GPIO_LIB" +To support this framework, a platform's Kconfig will "select" either +ARCH_REQUIRE_GPIOLIB or ARCH_WANT_OPTIONAL_GPIOLIB and arrange that its <asm/gpio.h> includes <asm-generic/gpio.h> and defines three functions: gpio_get_value(), gpio_set_value(), and gpio_cansleep(). They may also want to provide a custom value for ARCH_NR_GPIOS. +ARCH_REQUIRE_GPIOLIB means that the gpio-lib code will always get compiled +into the kernel on that architecture. + +ARCH_WANT_OPTIONAL_GPIOLIB means the gpio-lib code defaults to off and the user +can enable it and build it into the kernel optionally. + +If neither of these options are selected, the platform does not support +GPIOs through GPIO-lib and the code cannot be enabled by the user. + Trivial implementations of those functions can directly use framework code, which always dispatches through the gpio_chip:
arch/arm/Kconfig +4 -4
@@ -262,7 +262,7 @@ select ARM_AMBA select ARM_VIC select GENERIC_GPIO - select HAVE_GPIO_LIB + select ARCH_REQUIRE_GPIOLIB help This enables support for the Cirrus EP93xx series of CPUs.
@@ -430,7 +430,7 @@ depends on MMU select ARCH_MTD_XIP select GENERIC_GPIO - select HAVE_GPIO_LIB + select ARCH_REQUIRE_GPIOLIB select GENERIC_TIME select GENERIC_CLOCKEVENTS select TICK_ONESHOT
@@ -460,7 +460,7 @@ select GENERIC_TIME select GENERIC_CLOCKEVENTS select TICK_ONESHOT - select HAVE_GPIO_LIB + select ARCH_REQUIRE_GPIOLIB help Support for StrongARM 11x0 based boards.
@@ -500,7 +500,7 @@ config ARCH_OMAP bool "TI OMAP" select GENERIC_GPIO - select HAVE_GPIO_LIB + select ARCH_REQUIRE_GPIOLIB select GENERIC_TIME select GENERIC_CLOCKEVENTS help
arch/arm/configs/am200epdkit_defconfig +1 -1
@@ -668,7 +668,7 @@ # # CONFIG_SPI is not set # CONFIG_SPI_MASTER is not set -CONFIG_HAVE_GPIO_LIB=y +CONFIG_ARCH_REQUIRE_GPIOLIB=y # # GPIO Support
arch/avr32/Kconfig +1 -1
@@ -87,7 +87,7 @@ select SUBARCH_AVR32B select MMU select PERFORMANCE_COUNTERS - select HAVE_GPIO_LIB + select ARCH_REQUIRE_GPIOLIB select GENERIC_ALLOCATOR #
arch/avr32/configs/atngw100_defconfig +1 -1
@@ -646,7 +646,7 @@ # CONFIG_SPI_AT25 is not set CONFIG_SPI_SPIDEV=m # CONFIG_SPI_TLE62X0 is not set -CONFIG_HAVE_GPIO_LIB=y +CONFIG_ARCH_REQUIRE_GPIOLIB=y # # GPIO Support
arch/avr32/configs/atstk1002_defconfig +1 -1
@@ -664,7 +664,7 @@ # CONFIG_SPI_AT25 is not set CONFIG_SPI_SPIDEV=m # CONFIG_SPI_TLE62X0 is not set -CONFIG_HAVE_GPIO_LIB=y +CONFIG_ARCH_REQUIRE_GPIOLIB=y # # GPIO Support
arch/avr32/configs/atstk1003_defconfig +1 -1
@@ -614,7 +614,7 @@ # CONFIG_SPI_AT25 is not set CONFIG_SPI_SPIDEV=m # CONFIG_SPI_TLE62X0 is not set -CONFIG_HAVE_GPIO_LIB=y +CONFIG_ARCH_REQUIRE_GPIOLIB=y # # GPIO Support
arch/avr32/configs/atstk1004_defconfig +1 -1
@@ -390,7 +390,7 @@ # CONFIG_SPI_AT25 is not set # CONFIG_SPI_SPIDEV is not set # CONFIG_SPI_TLE62X0 is not set -CONFIG_HAVE_GPIO_LIB=y +CONFIG_ARCH_REQUIRE_GPIOLIB=y # # GPIO Support
arch/mips/Kconfig +1 -1
@@ -800,7 +800,7 @@ config GPIO_TXX9 select GENERIC_GPIO - select HAVE_GPIO_LIB + select ARCH_REQUIRE_GPIOLIB bool config CFE
arch/powerpc/platforms/52xx/Kconfig +1 -1
@@ -47,6 +47,6 @@ config PPC_MPC5200_GPIO bool "MPC5200 GPIO support" depends on PPC_MPC52xx - select HAVE_GPIO_LIB + select ARCH_REQUIRE_GPIOLIB help Enable gpiolib support for mpc5200 based boards
drivers/Makefile +1 -1
@@ -5,7 +5,7 @@ # Rewritten to use lists instead of if-statements. # -obj-$(CONFIG_HAVE_GPIO_LIB) += gpio/ +obj-y += gpio/ obj-$(CONFIG_PCI) += pci/ obj-$(CONFIG_PARISC) += parisc/ obj-$(CONFIG_RAPIDIO) += rapidio/
drivers/i2c/chips/Kconfig +1 -1
@@ -126,7 +126,7 @@ config TPS65010 tristate "TPS6501x Power Management chips" - depends on HAVE_GPIO_LIB + depends on GPIOLIB default y if MACH_OMAP_H2 || MACH_OMAP_H3 || MACH_OMAP_OSK help If you say yes here you get support for the TPS6501x series of
drivers/mfd/Kconfig +2 -2
@@ -28,7 +28,7 @@ config HTC_EGPIO bool "HTC EGPIO support" - depends on GENERIC_HARDIRQS && HAVE_GPIO_LIB && ARM + depends on GENERIC_HARDIRQS && GPIOLIB && ARM help This driver supports the CPLD egpio chip present on several HTC phones. It provides basic support for input
@@ -44,7 +44,7 @@ config MFD_TC6393XB bool "Support Toshiba TC6393XB" - depends on HAVE_GPIO_LIB + depends on GPIOLIB select MFD_CORE help Support for Toshiba Mobile IO Controller TC6393XB
drivers/of/Kconfig +1 -1
@@ -4,7 +4,7 @@ config OF_GPIO def_bool y - depends on OF && PPC_OF && HAVE_GPIO_LIB + depends on OF && PPC_OF && GPIOLIB help OpenFirmware GPIO accessors
include/asm-generic/gpio.h +1 -1
@@ -3,7 +3,7 @@#include <linux/types.h> -#ifdef CONFIG_HAVE_GPIO_LIB +#ifdef CONFIG_GPIOLIB #include <linux/compiler.h>
include/asm-mips/mach-generic/gpio.h +1 -1
@@ -1,7 +1,7 @@#ifndef __ASM_MACH_GENERIC_GPIO_H#define __ASM_MACH_GENERIC_GPIO_H -#ifdef CONFIG_HAVE_GPIO_LIB +#ifdef CONFIG_GPIOLIB #define gpio_get_value __gpio_get_value#define gpio_set_value __gpio_set_value#define gpio_cansleep __gpio_cansleep
include/asm-powerpc/gpio.h +2 -2
@@ -17,7 +17,7 @@#include <linux/errno.h> #include <asm-generic/gpio.h> -#ifdef CONFIG_HAVE_GPIO_LIB +#ifdef CONFIG_GPIOLIB /* * We don't (yet) implement inlined/rapid versions for on-chip gpios.
@@ -51,6 +51,6 @@return -EINVAL ; } -#endif /* CONFIG_HAVE_GPIO_LIB */ +#endif /* CONFIG_GPIOLIB */ #endif /* __ASM_POWERPC_GPIO_H */
arch/arm/configs/xm_x270_defconfig +1 -1
@@ -970,7 +970,7 @@ # CONFIG_I2C_DEBUG_BUS is not set # CONFIG_I2C_DEBUG_CHIP is not set # CONFIG_SPI is not set -CONFIG_HAVE_GPIO_LIB=y +CONFIG_ARCH_REQUIRE_GPIOLIB=y # # GPIO Support
arch/powerpc/configs/83xx/mpc836x_rdk_defconfig +1 -1
@@ -703,7 +703,7 @@ # CONFIG_SPI_AT25 is not set CONFIG_SPI_SPIDEV=y # CONFIG_SPI_TLE62X0 is not set -CONFIG_HAVE_GPIO_LIB=y +CONFIG_ARCH_REQUIRE_GPIOLIB=y # # GPIO Support
arch/powerpc/sysdev/qe_lib/Kconfig +1 -1
@@ -29,7 +29,7 @@ bool "QE GPIO support" depends on QUICC_ENGINE select GENERIC_GPIO - select HAVE_GPIO_LIB + select ARCH_REQUIRE_GPIOLIB help Say Y here if you're going to use hardware that connects to the QE GPIOs.
Signature · 1 line
Greetings Michael.
Quoted 31 lines · Michael Buesch
...
drivers/gpio/Kconfig +18
-1@@ -2,15 +2,40 @@ # GPIO infrastructure and expanders # -config HAVE_GPIO_LIB +config ARCH_WANT_OPTIONAL_GPIOLIB bool help + Select this config option from the architecture Kconfig, if + it is possible to use gpiolib on the architecture, but let the + user decide whether to actually build it or not. + Select this instead of ARCH_REQUIRE_GPIOLIB, if your architecture does + not depend on GPIOs being available, but rather let the user + decide whether he needs it or not. + +config ARCH_REQUIRE_GPIOLIB + bool + select GPIOLIB + help Platforms select gpiolib if they use this infrastructure for all their GPIOs, usually starting with ones integrated into SOC processors. + Selecting this from the architecture code will cause the gpiolib + code to always get built in. + + + +menuconfig GPIOLIB
drivers/gpio/Kconfig line 36
Quoted 10 lines
drivers/gpio/Kconfig +9
-0+ bool "GPIO Support" + depends on ARCH_WANT_OPTIONAL_GPIOLIB || ARCH_REQUIRE_GPIOLIB + select GENERIC_GPIO + help + This enables GPIO support through the generic GPIO library. + You only need to enable this, if you also want to enable + one or more of the GPIO expansion card drivers below. + + If unsure, say N.
The implementation of ARCH_REQUIRE_GPIOLIB does not match the description.
Matching the description would be:
menuconfig GPIOLIB
bool "GPIO Support" if !ARCH_REQUIRE_GPIOLIB
depends on ARCH_WANT_OPTIONAL_GPIOLIB || ARCH_REQUIRE_GPIOLIB
default ARCH_REQUIRE_GPIOLIB
select GENERIC_GPIO
help
...arch/arm/configs/am200epdkit_defconfig line 671
Quoted 9 lines
arch/arm/configs/am200epdkit_defconfig +1
-1@@ -668,7 +668,7 @@ # # CONFIG_SPI is not set # CONFIG_SPI_MASTER is not set -CONFIG_HAVE_GPIO_LIB=y +CONFIG_ARCH_REQUIRE_GPIOLIB=y
Please don't do this kind of defconfig updates - it doesn't bring any advantage but can create tons of patch conflicts.
The next time a defconfig gets updated it will anyway automatically be fixed, and for defconfigs that aren't updated it doesn't create any problems to keep them as they are today until they might one day get updated.
Quoted 1 line
Greetings Michael.
cu
Adrian
Signature · 4 lines
"Is there not promise of rain?" Ling Tan asked suddenly out
of the darkness. There had been need of rain for many days.
"Only a promise," Lao Er said.
Pearl S. Buck - Dragon SeedQuoted 16 lines · On Sunday 06 July 2008 21:52:12 Adrian Bunk wrote:
drivers/gpio/Kconfig line 36
Quoted 11 lines
drivers/gpio/Kconfig +10
-0+menuconfig GPIOLIB + bool "GPIO Support" + depends on ARCH_WANT_OPTIONAL_GPIOLIB || ARCH_REQUIRE_GPIOLIB + select GENERIC_GPIO + help + This enables GPIO support through the generic GPIO library. + You only need to enable this, if you also want to enable + one or more of the GPIO expansion card drivers below. + + If unsure, say N.The implementation of
ARCH_REQUIRE_GPIOLIBdoes not match the description.Matching the description would be:
Quoted 7 lines
menuconfig GPIOLIB
bool "GPIO Support" if !ARCH_REQUIRE_GPIOLIB depends on ARCH_WANT_OPTIONAL_GPIOLIB || ARCH_REQUIRE_GPIOLIB default ARCH_REQUIRE_GPIOLIB select GENERIC_GPIO help ...
So well. I'm not sure what you're talking about. Care to make a better helptext?
Quoted 13 lines
arch/arm/configs/am200epdkit_defconfig line 671
Quoted 9 lines
arch/arm/configs/am200epdkit_defconfig +1
-1@@ -668,7 +668,7 @@ # # CONFIG_SPI is not set # CONFIG_SPI_MASTER is not set -CONFIG_HAVE_GPIO_LIB=y +CONFIG_ARCH_REQUIRE_GPIOLIB=yPlease don't do this kind of defconfig updates - it doesn't bring any advantage but can create tons of patch conflicts.
Quoted 4 lines
The next time a defconfig gets updated it will anyway automatically be fixed, and for defconfigs that aren't updated it doesn't create any problems to keep them as they are today until they might one day get updated.
So will the auto-regenerated defconfig result in CONFIG_ARCH_REQUIRE_GPIOLIB=y or CONFIG_ARCH_REQUIRE_GPIOLIB=n? I thought it would result in =n, as the option defaults to n. So I changed all defconfigs.
(I think these (sub)archs should "select" the option in their Kconfig, but I didn't want to go down that way).
Signature · 1 line
Greetings Michael.
Quoted 4 lines · Michael Buesch
On Sunday 06 July 2008 21:52:12 Adrian Bunk wrote:
...
So well. I'm not sure what you're talking about. Care to make a better helptext?
Sorry, the problem wasn't the help text but me being blind.
Please ignore my comment.
Quoted 18 lines
Quoted 13 lines
arch/arm/configs/am200epdkit_defconfig line 671
Quoted 9 lines
arch/arm/configs/am200epdkit_defconfig +1
-1@@ -668,7 +668,7 @@ # # CONFIG_SPI is not set # CONFIG_SPI_MASTER is not set -CONFIG_HAVE_GPIO_LIB=y +CONFIG_ARCH_REQUIRE_GPIOLIB=yPlease don't do this kind of defconfig updates - it doesn't bring any advantage but can create tons of patch conflicts.
Quoted 4 lines
The next time a defconfig gets updated it will anyway automatically be fixed, and for defconfigs that aren't updated it doesn't create any problems to keep them as they are today until they might one day get updated.
Quoted 6 lines
So will the auto-regenerated defconfig result in
CONFIG_ARCH_REQUIRE_GPIOLIB=yorCONFIG_ARCH_REQUIRE_GPIOLIB=n? I thought it would result in =n, as the option defaults to n. So I changed all defconfigs.(I think these (sub)archs should "select" the option in their
Kconfig, but I didn't want to go down that way).
A defconfig is just a normal .config and cannot override any dependencies.
CONFIG_ARCH_REQUIRE_GPIOLIB is not user visible and defaults to n, so if no option select's it then even using a defconfig that has it enabled will result in a .config that has it disabled.
Quoted 1 line
Greetings Michael.
cu
Adrian
Signature · 4 lines
"Is there not promise of rain?" Ling Tan asked suddenly out
of the darkness. There had been need of rain for many days.
"Only a promise," Lao Er said.
Pearl S. Buck - Dragon SeedQuoted 5 lines · On Sunday 06 July 2008 22:13:46 Adrian Bunk wrote:
A defconfig is just a normal .config and cannot override any dependencies.
CONFIG_ARCH_REQUIRE_GPIOLIBis not user visible and defaults to n, so if no option select's it then even using a defconfig that has it enabled will result in a .config that has it disabled.
Ok, thanks a lot for explaining this to me. :)
Signature · 1 line
Greetings Michael.