summaryrefslogtreecommitdiffstats
path: root/include/asm-arm/arch-davinci/gpio.h
blob: ea24a0e0bfd672137d686b57c4277d51566f7c36 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
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 */