[ARM] 4457/2: davinci: GPIO support

Support GPIO driver for TI DaVinci SoC

Signed-off-by: Vladimir Barinov <vbarino@ru.mvista.com>
Acked-by: David Brownell <david-b@pacbell.net>
Acked-by: Kevin Hilman <khilman@mvista.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 156 insertions, 0 deletions

diff --git a/include/asm-arm/arch-davinci/gpio.h b/include/asm-arm/arch-davinci/gpio.h
new file mode 100644
index 000000000000..ea24a0e0bfd6
--- /dev/null
+++ b/include/asm-arm/arch-davinci/gpio.h
@@ -0,0 +1,156 @@
+/*
+ * TI DaVinci GPIO Support
+ *
+ * Copyright (c) 2006 David Brownell
+ * Copyright (c) 2007, MontaVista Software, Inc. <source@mvista.com>
+ *
+ * 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 __DAVINCI_GPIO_H
+#define __DAVINCI_GPIO_H
+
+/*
+ * basic gpio routines
+ *
+ * board-specific init should be done by arch/.../.../board-XXX.c (maybe
+ * initializing banks together) rather than boot loaders; kexec() won't
+ * go through boot loaders.
+ *
+ * the gpio clock will be turned on when gpios are used, and you may also
+ * need to pay attention to PINMUX0 and PINMUX1 to be sure those pins are
+ * used as gpios, not with other peripherals.
+ *
+ * GPIOs are numbered 0..(DAVINCI_N_GPIO-1).  For documentation, and maybe
+ * for later updates, code should write GPIO(N) or:
+ *  - GPIOV18(N) for 1.8V pins, N in 0..53; same as GPIO(0)..GPIO(53)
+ *  - GPIOV33(N) for 3.3V pins, N in 0..17; same as GPIO(54)..GPIO(70)
+ *
+ * For GPIO IRQs use gpio_to_irq(GPIO(N)) or gpio_to_irq(GPIOV33(N)) etc
+ * for now, that's != GPIO(N)
+ */
+#define GPIO(X)         (X)             /* 0 <= X <= 70 */
+#define GPIOV18(X)      (X)             /* 1.8V i/o; 0 <= X <= 53 */
+#define GPIOV33(X)      ((X)+54)        /* 3.3V i/o; 0 <= X <= 17 */
+
+struct gpio_controller {
+        u32     dir;
+        u32     out_data;
+        u32     set_data;
+        u32     clr_data;
+        u32     in_data;
+        u32     set_rising;
+        u32     clr_rising;
+        u32     set_falling;
+        u32     clr_falling;
+        u32     intstat;
+};
+
+/* The __gpio_to_controller() and __gpio_mask() functions inline to constants
+ * with constant parameters; or in outlined code they execute at runtime.
+ *
+ * You'd access the controller directly when reading or writing more than
+ * one gpio value at a time, and to support wired logic where the value
+ * being driven by the cpu need not match the value read back.
+ *
+ * These are NOT part of the cross-platform GPIO interface
+ */
+static inline struct gpio_controller *__iomem
+__gpio_to_controller(unsigned gpio)
+{
+        void *__iomem ptr;
+
+        if (gpio < 32)
+                ptr = (void *__iomem)IO_ADDRESS(DAVINCI_GPIO_BASE + 0x10);
+        else if (gpio < 64)
+                ptr = (void *__iomem)IO_ADDRESS(DAVINCI_GPIO_BASE + 0x38);
+        else if (gpio < DAVINCI_N_GPIO)
+                ptr = (void *__iomem)IO_ADDRESS(DAVINCI_GPIO_BASE + 0x60);
+        else
+                ptr = NULL;
+        return ptr;
+}
+
+static inline u32 __gpio_mask(unsigned gpio)
+{
+        return 1 << (gpio % 32);
+}
+
+/* The get/set/clear functions will inline when called with constant
+ * parameters, for low-overhead bitbanging.  Illegal constant parameters
+ * cause link-time errors.
+ *
+ * Otherwise, calls with variable parameters use outlined functions.
+ */
+extern int __error_inval_gpio(void);
+
+extern void __gpio_set(unsigned gpio, int value);
+extern int __gpio_get(unsigned gpio);
+
+static inline void gpio_set_value(unsigned gpio, int value)
+{
+        if (__builtin_constant_p(value)) {
+                struct gpio_controller  *__iomem g;
+                u32                     mask;
+
+                if (gpio >= DAVINCI_N_GPIO)
+                        __error_inval_gpio();
+
+                g = __gpio_to_controller(gpio);
+                mask = __gpio_mask(gpio);
+                if (value)
+                        __raw_writel(mask, &g->set_data);
+                else
+                        __raw_writel(mask, &g->clr_data);
+                return;
+        }
+
+        __gpio_set(gpio, value);
+}
+
+/* Returns zero or nonzero; works for gpios configured as inputs OR
+ * as outputs.
+ *
+ * NOTE: changes in reported values are synchronized to the GPIO clock.
+ * This is most easily seen after calling gpio_set_value() and then immediatly
+ * gpio_get_value(), where the gpio_get_value() would return the old value
+ * until the GPIO clock ticks and the new value gets latched.
+ */
+
+static inline int gpio_get_value(unsigned gpio)
+{
+        struct gpio_controller *__iomem g;
+
+        if (!__builtin_constant_p(gpio))
+                return __gpio_get(gpio);
+
+        if (gpio >= DAVINCI_N_GPIO)
+                return __error_inval_gpio();
+
+        g = __gpio_to_controller(gpio);
+        return !!(__gpio_mask(gpio) & __raw_readl(&g->in_data));
+}
+
+/* powerup default direction is IN */
+extern int gpio_direction_input(unsigned gpio);
+extern int gpio_direction_output(unsigned gpio, int value);
+
+#include <asm-generic/gpio.h>   /* cansleep wrappers */
+
+extern int gpio_request(unsigned gpio, const char *tag);
+extern void gpio_free(unsigned gpio);
+
+static inline int gpio_to_irq(unsigned gpio)
+{
+        return DAVINCI_N_AINTC_IRQ + gpio;
+}
+
+static inline int irq_to_gpio(unsigned irq)
+{
+        return irq - DAVINCI_N_AINTC_IRQ;
+}
+
+#endif                          /* __DAVINCI_GPIO_H */