aboutsummaryrefslogtreecommitdiffstats
path: root/arch/arm/mach-ns9xxx/gpio.c
blob: b2230213b983deacd3db7e0a251fc1d27b9f2e69 (plain) (blame)
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
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
/*
 * 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/io.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 void __iomem *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 void __iomem *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 void __iomem *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)
{
	void __iomem *conf = ns9xxx_gpio_get_gconfaddr(gpio);
	u32 confval;
	unsigned long flags;

	spin_lock_irqsave(&gpio_lock, flags);

	confval = __raw_readl(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);
	__raw_writel(confval, conf);

	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)
{
	void __iomem *stat = ns9xxx_gpio_get_gstataddr(gpio);
	int ret;

	ret = 1 & (__raw_readl(stat) >> (gpio & 31));

	return ret;
}
EXPORT_SYMBOL(gpio_get_value);

void gpio_set_value(unsigned gpio, int value)
{
	void __iomem *ctrl = ns9xxx_gpio_get_gctrladdr(gpio);
	u32 ctrlval;
	unsigned long flags;

	spin_lock_irqsave(&gpio_lock, flags);

	ctrlval = __raw_readl(ctrl);

	if (value)
		ctrlval |= 1 << (gpio & 31);
	else
		ctrlval &= ~(1 << (gpio & 31));

	__raw_writel(ctrlval, ctrl);

	spin_unlock_irqrestore(&gpio_lock, flags);
}
EXPORT_SYMBOL(gpio_set_value);