[ARM] 4590/1: ns9xxx: add gpio handling functions

This implementation conforms to the general GPIO API
introduced in 2.6.21.

This patch was signed-of by David Brownell before I exported the functions
using EXPORT_SYMBOL.

Signed-off-by: Uwe Kleine-König <ukleinek@informatik.uni-freiburg.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 691aae309c8af1f04ec2cfafcae74fb1b482fd3a..6acc59da332d7a32871eff9279e5db2aa954c244 100644 (file)
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -318,6 +318,7 @@ config ARCH_KS8695
 
 config ARCH_NS9XXX
        bool "NetSilicon NS9xxx"
+       select GENERIC_GPIO
        help
          Say Y here if you intend to run this kernel on a NetSilicon NS9xxx
          System.

diff --git a/arch/arm/mach-ns9xxx/Makefile b/arch/arm/mach-ns9xxx/Makefile
index 4476411b81408704f9d430e51715d1232f95c2d5..6fb82b855a55aa6a81b8f525d7db816b8b5d4bad 100644 (file)
--- a/arch/arm/mach-ns9xxx/Makefile
+++ b/arch/arm/mach-ns9xxx/Makefile
@@ -1,4 +1,4 @@
-obj-y := irq.o time.o generic.o
+obj-y := irq.o time.o generic.o gpio.o
 
 obj-$(CONFIG_MACH_CC9P9360DEV) += mach-cc9p9360dev.o
 obj-$(CONFIG_MACH_CC9P9360JS) += mach-cc9p9360js.o

diff --git a/arch/arm/mach-ns9xxx/gpio.c b/arch/arm/mach-ns9xxx/gpio.c
new file mode 100644 (file)
index 0000000..87b872f
--- /dev/null
+++ b/arch/arm/mach-ns9xxx/gpio.c
@@ -0,0 +1,184 @@
+/*
+ * arch/arm/mach-ns9xxx/gpio.c
+ *
+ * Copyright (C) 2006 by Digi International Inc.
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ */
+#include <linux/compiler.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/module.h>
+
+#include <asm/arch-ns9xxx/gpio.h>
+#include <asm/arch-ns9xxx/processor.h>
+#include <asm/arch-ns9xxx/regs-bbu.h>
+#include <asm/bug.h>
+#include <asm/types.h>
+#include <asm/bitops.h>
+
+#if defined(CONFIG_PROCESSOR_NS9360)
+#define GPIO_MAX 72
+#elif defined(CONFIG_PROCESSOR_NS9750)
+#define GPIO_MAX 49
+#endif
+
+/* protects BBU_GCONFx and BBU_GCTRLx */
+static spinlock_t gpio_lock = __SPIN_LOCK_UNLOCKED(gpio_lock);
+
+/* only access gpiores with atomic ops */
+static DECLARE_BITMAP(gpiores, GPIO_MAX);
+
+static inline int ns9xxx_valid_gpio(unsigned gpio)
+{
+#if defined(CONFIG_PROCESSOR_NS9360)
+       if (processor_is_ns9360())
+               return gpio <= 72;
+       else
+#endif
+#if defined(CONFIG_PROCESSOR_NS9750)
+       if (processor_is_ns9750())
+               return gpio <= 49;
+       else
+#endif
+               BUG();
+}
+
+static inline volatile u32 *ns9xxx_gpio_get_gconfaddr(unsigned gpio)
+{
+       if (gpio < 56)
+               return &BBU_GCONFb1(gpio / 8);
+       else
+               /*
+                * this could be optimised away on
+                * ns9750 only builds, but it isn't ...
+                */
+               return &BBU_GCONFb2((gpio - 56) / 8);
+}
+
+static inline volatile u32 *ns9xxx_gpio_get_gctrladdr(unsigned gpio)
+{
+       if (gpio < 32)
+               return &BBU_GCTRL1;
+       else if (gpio < 64)
+               return &BBU_GCTRL2;
+       else
+               /* this could be optimised away on ns9750 only builds */
+               return &BBU_GCTRL3;
+}
+
+static inline volatile u32 *ns9xxx_gpio_get_gstataddr(unsigned gpio)
+{
+       if (gpio < 32)
+               return &BBU_GSTAT1;
+       else if (gpio < 64)
+               return &BBU_GSTAT2;
+       else
+               /* this could be optimised away on ns9750 only builds */
+               return &BBU_GSTAT3;
+}
+
+int gpio_request(unsigned gpio, const char *label)
+{
+       if (likely(ns9xxx_valid_gpio(gpio)))
+               return test_and_set_bit(gpio, gpiores) ? -EBUSY : 0;
+       else
+               return -EINVAL;
+}
+EXPORT_SYMBOL(gpio_request);
+
+void gpio_free(unsigned gpio)
+{
+       clear_bit(gpio, gpiores);
+       return;
+}
+EXPORT_SYMBOL(gpio_free);
+
+/*
+ * each gpio can serve for 4 different purposes [0..3].  These are called
+ * "functions" and passed in the parameter func.  Functions 0-2 are always some
+ * special things, function 3 is GPIO.  If func == 3 dir specifies input or
+ * output, and with inv you can enable an inverter (independent of func).
+ */
+static int __ns9xxx_gpio_configure(unsigned gpio, int dir, int inv, int func)
+{
+       volatile u32 *conf = ns9xxx_gpio_get_gconfaddr(gpio);
+       u32 confval;
+       unsigned long flags;
+
+       spin_lock_irqsave(&gpio_lock, flags);
+
+       confval = *conf;
+       REGSETIM_IDX(confval, BBU_GCONFx, DIR, gpio & 7, dir);
+       REGSETIM_IDX(confval, BBU_GCONFx, INV, gpio & 7, inv);
+       REGSETIM_IDX(confval, BBU_GCONFx, FUNC, gpio & 7, func);
+       *conf = confval;
+
+       spin_unlock_irqrestore(&gpio_lock, flags);
+
+       return 0;
+}
+
+int ns9xxx_gpio_configure(unsigned gpio, int inv, int func)
+{
+       if (likely(ns9xxx_valid_gpio(gpio))) {
+               if (func == 3) {
+                       printk(KERN_WARNING "use gpio_direction_input "
+                                       "or gpio_direction_output\n");
+                       return -EINVAL;
+               } else
+                       return __ns9xxx_gpio_configure(gpio, 0, inv, func);
+       } else
+               return -EINVAL;
+}
+EXPORT_SYMBOL(ns9xxx_gpio_configure);
+
+int gpio_direction_input(unsigned gpio)
+{
+       if (likely(ns9xxx_valid_gpio(gpio))) {
+               return __ns9xxx_gpio_configure(gpio, 0, 0, 3);
+       } else
+               return -EINVAL;
+}
+EXPORT_SYMBOL(gpio_direction_input);
+
+int gpio_direction_output(unsigned gpio, int value)
+{
+       if (likely(ns9xxx_valid_gpio(gpio))) {
+               gpio_set_value(gpio, value);
+
+               return __ns9xxx_gpio_configure(gpio, 1, 0, 3);
+       } else
+               return -EINVAL;
+}
+EXPORT_SYMBOL(gpio_direction_output);
+
+int gpio_get_value(unsigned gpio)
+{
+       volatile u32 *stat = ns9xxx_gpio_get_gstataddr(gpio);
+       int ret;
+
+       ret = 1 & (*stat >> (gpio & 31));
+
+       return ret;
+}
+EXPORT_SYMBOL(gpio_get_value);
+
+void gpio_set_value(unsigned gpio, int value)
+{
+       volatile u32 *ctrl = ns9xxx_gpio_get_gctrladdr(gpio);
+       unsigned long flags;
+
+       spin_lock_irqsave(&gpio_lock, flags);
+
+       if (value)
+               *ctrl |= 1 << (gpio & 31);
+       else
+               *ctrl &= ~(1 << (gpio & 31));
+
+       spin_unlock_irqrestore(&gpio_lock, flags);
+}
+EXPORT_SYMBOL(gpio_set_value);

diff --git a/include/asm-arm/arch-ns9xxx/gpio.h b/include/asm-arm/arch-ns9xxx/gpio.h
new file mode 100644 (file)
index 0000000..adbca08
--- /dev/null
+++ b/include/asm-arm/arch-ns9xxx/gpio.h
@@ -0,0 +1,47 @@
+/*
+ * include/asm-arm/arch-ns9xxx/gpio.h
+ *
+ * Copyright (C) 2007 by Digi International Inc.
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+*/
+#ifndef __ASM_ARCH_GPIO_H
+#define __ASM_ARCH_GPIO_H
+
+#include <asm/errno.h>
+
+int gpio_request(unsigned gpio, const char *label);
+
+void gpio_free(unsigned gpio);
+
+int ns9xxx_gpio_configure(unsigned gpio, int inv, int func);
+
+int gpio_direction_input(unsigned gpio);
+
+int gpio_direction_output(unsigned gpio, int value);
+
+int gpio_get_value(unsigned gpio);
+
+void gpio_set_value(unsigned gpio, int value);
+
+/*
+ * ns9xxx can use gpio pins to trigger an irq, but it's not generic
+ * enough to be supported by the gpio_to_irq/irq_to_gpio interface
+ */
+static inline int gpio_to_irq(unsigned gpio)
+{
+       return -EINVAL;
+}
+
+static inline int irq_to_gpio(unsigned irq)
+{
+       return -EINVAL;
+}
+
+/* get the cansleep() stubs */
+#include <asm-generic/gpio.h>
+
+#endif /* ifndef __ASM_ARCH_GPIO_H */