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From b77665c545bc260d2b93add129413e4a724d7e6e Mon Sep 17 00:00:00 2001
From: David Brownell <dbrownell@users.sourceforge.net>
Date: Fri, 18 Jan 2008 00:35:00 +0300
Subject: [PATCH 21/64] 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>
---
arch/arm/Kconfig | 2 ++
drivers/Kconfig | 2 ++
drivers/Makefile | 1 +
drivers/gpio/Kconfig | 32 ++++++++++++++++++++++++++++++++
drivers/gpio/Makefile | 3 +++
5 files changed, 40 insertions(+), 0 deletions(-)
create mode 100644 drivers/gpio/Kconfig
create mode 100644 drivers/gpio/Makefile
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 10faf9c..06ca241 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1042,6 +1042,8 @@ source "drivers/i2c/Kconfig"
source "drivers/spi/Kconfig"
+source "drivers/gpio/Kconfig"
+
source "drivers/w1/Kconfig"
source "drivers/power/Kconfig"
diff --git a/drivers/Kconfig b/drivers/Kconfig
index f4076d9..90e295a 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -52,6 +52,8 @@ source "drivers/i2c/Kconfig"
source "drivers/spi/Kconfig"
+source "drivers/gpio/Kconfig"
+
source "drivers/w1/Kconfig"
source "drivers/power/Kconfig"
diff --git a/drivers/Makefile b/drivers/Makefile
index 8cb37e3..8e5101f 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -5,6 +5,7 @@
# Rewritten to use lists instead of if-statements.
#
+obj-$(CONFIG_HAVE_GPIO_LIB) += gpio/
obj-$(CONFIG_PCI) += pci/
obj-$(CONFIG_PARISC) += parisc/
obj-$(CONFIG_RAPIDIO) += rapidio/
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
new file mode 100644
index 0000000..560687c
--- /dev/null
+++ b/drivers/gpio/Kconfig
@@ -0,0 +1,32 @@
+#
+# GPIO infrastructure and expanders
+#
+
+config HAVE_GPIO_LIB
+ bool
+ help
+ Platforms select gpiolib if they use this infrastructure
+ for all their GPIOs, usually starting with ones integrated
+ into SOC processors.
+
+menu "GPIO Support"
+ depends on HAVE_GPIO_LIB
+
+config DEBUG_GPIO
+ bool "Debug GPIO calls"
+ depends on DEBUG_KERNEL
+ help
+ Say Y here to add some extra checks and diagnostics to GPIO calls.
+ The checks help ensure that GPIOs have been properly initialized
+ before they are used and that sleeping calls aren not made from
+ nonsleeping contexts. They can make bitbanged serial protocols
+ slower. The diagnostics help catch the type of setup errors
+ that are most common when setting up new platforms or boards.
+
+# put expanders in the right section, in alphabetical order
+
+comment "I2C GPIO expanders:"
+
+comment "SPI GPIO expanders:"
+
+endmenu
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
new file mode 100644
index 0000000..cdbba6b
--- /dev/null
+++ b/drivers/gpio/Makefile
@@ -0,0 +1,3 @@
+# gpio support: dedicated expander chips, etc
+
+ccflags-$(CONFIG_DEBUG_GPIO) += -DDEBUG
--
1.5.3.8
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