This patch implements support for the GPIO LIB API. Two calls
unimplemented though: irq_to_gpio and gpio_to_irq.
Signed-off-by: Anton Vorontsov <[EMAIL PROTECTED]>
---
Documentation/powerpc/booting-without-of.txt | 52 ++++++++++++++++++++++++
arch/powerpc/Kconfig | 5 ++
include/asm-powerpc/gpio.h | 56 ++++++++++++++++++++++++++
3 files changed, 113 insertions(+), 0 deletions(-)
create mode 100644 include/asm-powerpc/gpio.h
diff --git a/Documentation/powerpc/booting-without-of.txt
b/Documentation/powerpc/booting-without-of.txt
index b506245..e9e0c2f 100644
--- a/Documentation/powerpc/booting-without-of.txt
+++ b/Documentation/powerpc/booting-without-of.txt
@@ -66,6 +66,10 @@ Table of Contents
3) OpenPIC Interrupt Controllers
4) ISA Interrupt Controllers
+ VIII - Specifying GPIO information for devices
+ 1) gpios property
+ 2) gpio-controller nodes
+
Appendix A - Sample SOC node for MPC8540
@@ -2925,6 +2929,54 @@ encodings listed below:
2 = high to low edge sensitive type enabled
3 = low to high edge sensitive type enabled
+VIII - Specifying GPIO information for devices
+==============================================
+
+1) gpios property
+-----------------
+
+Nodes that makes use of GPIOs should define them using `gpios' property,
+format of which is: <&gpio-controller1-phandle gpio1-specifier
+ &gpio-controller2-phandle gpio2-specifier
+ 0 /* holes are permitted, means no GPIO 3 */
+ &gpio-controller4-phandle gpio4-specifier
+ ...>;
+
+Note that gpio-specifier length is controller dependent.
+
+gpio-specifier may encode: bank, pin position inside the bank,
+whether pin is open-drain and whether pin is logically inverted.
+
+Example of the node using GPIOs:
+
+ node {
+ gpios = <&qe_pio_e 18 0>;
+ };
+
+In this example gpio-specifier is "18 0" and encodes GPIO pin number,
+and empty GPIO flags as accepted by the "qe_pio_e" gpio-controller.
+
+2) gpio-controller nodes
+------------------------
+
+Every GPIO controller node must have #gpio-cells property defined,
+this information will be used to translate gpio-specifiers.
+
+Example of two SOC GPIO banks defined as gpio-controller nodes:
+
+ qe_pio_a: [EMAIL PROTECTED] {
+ #gpio-cells = <2>;
+ compatible = "fsl,qe-pario-bank-a", "fsl,qe-pario-bank";
+ reg = <0x1400 0x18>;
+ gpio-controller;
+ };
+
+ qe_pio_e: [EMAIL PROTECTED] {
+ #gpio-cells = <2>;
+ compatible = "fsl,qe-pario-bank-e", "fsl,qe-pario-bank";
+ reg = <0x1460 0x18>;
+ gpio-controller;
+ };
Appendix A - Sample SOC node for MPC8540
========================================
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 0b27cbd..f328509 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -81,6 +81,11 @@ config GENERIC_FIND_NEXT_BIT
bool
default y
+config GENERIC_GPIO
+ bool
+ help
+ Generic GPIO API support
+
config ARCH_NO_VIRT_TO_BUS
def_bool PPC64
diff --git a/include/asm-powerpc/gpio.h b/include/asm-powerpc/gpio.h
new file mode 100644
index 0000000..77ad3a8
--- /dev/null
+++ b/include/asm-powerpc/gpio.h
@@ -0,0 +1,56 @@
+/*
+ * Generic GPIO API implementation for PowerPC.
+ *
+ * Copyright (c) 2007-2008 MontaVista Software, Inc.
+ *
+ * Author: Anton Vorontsov <[EMAIL PROTECTED]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#ifndef __ASM_POWERPC_GPIO_H
+#define __ASM_POWERPC_GPIO_H
+
+#include <linux/errno.h>
+#include <asm-generic/gpio.h>
+
+#ifdef CONFIG_HAVE_GPIO_LIB
+
+/*
+ * We don't (yet) implement inlined/rapid versions for on-chip gpios.
+ * Just call gpiolib.
+ */
+static inline int gpio_get_value(unsigned int gpio)
+{
+ return __gpio_get_value(gpio);
+}
+
+static inline void gpio_set_value(unsigned int gpio, int value)
+{
+ __gpio_set_value(gpio, value);
+}
+
+static inline int gpio_cansleep(unsigned int gpio)
+{
+ return __gpio_cansleep(gpio);
+}
+
+/*
+ * Not implemented, yet.
+ */
+static inline int gpio_to_irq(unsigned int gpio)
+{
+ return -ENOSYS;
+}
+
+static inline int irq_to_gpio(unsigned int irq)
+{
+ return -EINVAL;
+}
+
+#endif /* CONFIG_HAVE_GPIO_LIB */
+
+#endif /* __ASM_POWERPC_GPIO_H */
--
1.5.4.5
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