aboutsummaryrefslogtreecommitdiff
path: root/arch/arm/plat-s5p/irq-gpioint.c
blob: 1fdfaa4599ced6465f647bc77578a92c9694b9bc (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
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
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
/* linux/arch/arm/plat-s5p/irq-gpioint.c
 *
 * Copyright (c) 2010 Samsung Electronics Co., Ltd.
 * Author: Kyungmin Park <kyungmin.park@samsung.com>
 * Author: Joonyoung Shim <jy0922.shim@samsung.com>
 * Author: Marek Szyprowski <m.szyprowski@samsung.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.
 *
 */

#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <linux/gpio.h>
#include <linux/slab.h>

#include <mach/map.h>
#include <plat/gpio-core.h>
#include <plat/gpio-cfg.h>

#include <asm/mach/irq.h>

#define GPIO_BASE(chip)		(((unsigned long)(chip)->base) & 0xFFFFF000u)

#define CON_OFFSET		0x700
#define MASK_OFFSET		0x900
#define PEND_OFFSET		0xA00
#define REG_OFFSET(x)		((x) << 2)

struct s5p_gpioint_bank {
	struct list_head	list;
	int			start;
	int			nr_groups;
	int			irq;
	struct samsung_gpio_chip	**chips;
	void			(*handler)(unsigned int, struct irq_desc *);
};

LIST_HEAD(banks);

static int s5p_gpioint_set_type(struct irq_data *d, unsigned int type)
{
	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
	struct irq_chip_type *ct = gc->chip_types;
	unsigned int shift = (d->irq - gc->irq_base) << 2;

	switch (type) {
	case IRQ_TYPE_EDGE_RISING:
		type = S5P_IRQ_TYPE_EDGE_RISING;
		break;
	case IRQ_TYPE_EDGE_FALLING:
		type = S5P_IRQ_TYPE_EDGE_FALLING;
		break;
	case IRQ_TYPE_EDGE_BOTH:
		type = S5P_IRQ_TYPE_EDGE_BOTH;
		break;
	case IRQ_TYPE_LEVEL_HIGH:
		type = S5P_IRQ_TYPE_LEVEL_HIGH;
		break;
	case IRQ_TYPE_LEVEL_LOW:
		type = S5P_IRQ_TYPE_LEVEL_LOW;
		break;
	case IRQ_TYPE_NONE:
	default:
		printk(KERN_WARNING "No irq type\n");
		return -EINVAL;
	}

	gc->type_cache &= ~(0x7 << shift);
	gc->type_cache |= type << shift;
	writel(gc->type_cache, gc->reg_base + ct->regs.type);
	return 0;
}

static void s5p_gpioint_handler(unsigned int irq, struct irq_desc *desc)
{
	struct s5p_gpioint_bank *bank = irq_get_handler_data(irq);
	int group, pend_offset, mask_offset;
	unsigned int pend, mask;

	struct irq_chip *chip = irq_get_chip(irq);
	chained_irq_enter(chip, desc);

	for (group = 0; group < bank->nr_groups; group++) {
		struct samsung_gpio_chip *chip = bank->chips[group];
		if (!chip)
			continue;

		pend_offset = REG_OFFSET(group);
		pend = __raw_readl(GPIO_BASE(chip) + PEND_OFFSET + pend_offset);
		if (!pend)
			continue;

		mask_offset = REG_OFFSET(group);
		mask = __raw_readl(GPIO_BASE(chip) + MASK_OFFSET + mask_offset);
		pend &= ~mask;

		while (pend) {
			int offset = fls(pend) - 1;
			int real_irq = chip->irq_base + offset;
			generic_handle_irq(real_irq);
			pend &= ~BIT(offset);
		}
	}
	chained_irq_exit(chip, desc);
}

static __init int s5p_gpioint_add(struct samsung_gpio_chip *chip)
{
	static int used_gpioint_groups = 0;
	int group = chip->group;
	struct s5p_gpioint_bank *b, *bank = NULL;
	struct irq_chip_generic *gc;
	struct irq_chip_type *ct;

	if (used_gpioint_groups >= S5P_GPIOINT_GROUP_COUNT)
		return -ENOMEM;

	list_for_each_entry(b, &banks, list) {
		if (group >= b->start && group < b->start + b->nr_groups) {
			bank = b;
			break;
		}
	}
	if (!bank)
		return -EINVAL;

	if (!bank->handler) {
		bank->chips = kzalloc(sizeof(struct samsung_gpio_chip *) *
				      bank->nr_groups, GFP_KERNEL);
		if (!bank->chips)
			return -ENOMEM;

		irq_set_chained_handler(bank->irq, s5p_gpioint_handler);
		irq_set_handler_data(bank->irq, bank);
		bank->handler = s5p_gpioint_handler;
		printk(KERN_INFO "Registered chained gpio int handler for interrupt %d.\n",
		       bank->irq);
	}

	/*
	 * chained GPIO irq has been successfully registered, allocate new gpio
	 * int group and assign irq nubmers
	 */
	chip->irq_base = S5P_GPIOINT_BASE +
			 used_gpioint_groups * S5P_GPIOINT_GROUP_SIZE;
	used_gpioint_groups++;

	bank->chips[group - bank->start] = chip;

	gc = irq_alloc_generic_chip("s5p_gpioint", 1, chip->irq_base,
				    (void __iomem *)GPIO_BASE(chip),
				    handle_level_irq);
	if (!gc)
		return -ENOMEM;
	ct = gc->chip_types;
	ct->chip.irq_ack = irq_gc_ack_set_bit;
	ct->chip.irq_mask = irq_gc_mask_set_bit;
	ct->chip.irq_unmask = irq_gc_mask_clr_bit;
	ct->chip.irq_set_type = s5p_gpioint_set_type,
	ct->regs.ack = PEND_OFFSET + REG_OFFSET(group - bank->start);
	ct->regs.mask = MASK_OFFSET + REG_OFFSET(group - bank->start);
	ct->regs.type = CON_OFFSET + REG_OFFSET(group - bank->start);
	irq_setup_generic_chip(gc, IRQ_MSK(chip->chip.ngpio),
			       IRQ_GC_INIT_MASK_CACHE,
			       IRQ_NOREQUEST | IRQ_NOPROBE, 0);
	return 0;
}

int __init s5p_register_gpio_interrupt(int pin)
{
	struct samsung_gpio_chip *my_chip = samsung_gpiolib_getchip(pin);
	int offset, group;
	int ret;

	if (!my_chip)
		return -EINVAL;

	offset = pin - my_chip->chip.base;
	group = my_chip->group;

	/* check if the group has been already registered */
	if (my_chip->irq_base)
		return my_chip->irq_base + offset;

	/* register gpio group */
	ret = s5p_gpioint_add(my_chip);
	if (ret == 0) {
		my_chip->chip.to_irq = samsung_gpiolib_to_irq;
		printk(KERN_INFO "Registered interrupt support for gpio group %d.\n",
		       group);
		return my_chip->irq_base + offset;
	}
	return ret;
}

int __init s5p_register_gpioint_bank(int chain_irq, int start, int nr_groups)
{
	struct s5p_gpioint_bank *bank;

	bank = kzalloc(sizeof(*bank), GFP_KERNEL);
	if (!bank)
		return -ENOMEM;

	bank->start = start;
	bank->nr_groups = nr_groups;
	bank->irq = chain_irq;

	list_add_tail(&bank->list, &banks);
	return 0;
}