summaryrefslogtreecommitdiffstats
path: root/drivers/irqchip/irq-tb10x.c
blob: 7c44c99bf1f2563f08656974068a2664a402e882 (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
/*
 * Abilis Systems interrupt controller driver
 *
 * Copyright (C) Abilis Systems 2012
 *
 * Author: Christian Ruppert <christian.ruppert@abilis.com>
 *
 * 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.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 */

#include <linux/interrupt.h>
#include <linux/irqdomain.h>
#include <linux/irq.h>
#include <linux/of_irq.h>
#include <linux/of_address.h>
#include <linux/of_platform.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/bitops.h>
#include "irqchip.h"

#define AB_IRQCTL_INT_ENABLE   0x00
#define AB_IRQCTL_INT_STATUS   0x04
#define AB_IRQCTL_SRC_MODE     0x08
#define AB_IRQCTL_SRC_POLARITY 0x0C
#define AB_IRQCTL_INT_MODE     0x10
#define AB_IRQCTL_INT_POLARITY 0x14
#define AB_IRQCTL_INT_FORCE    0x18

#define AB_IRQCTL_MAXIRQ       32

static inline void ab_irqctl_writereg(struct irq_chip_generic *gc, u32 reg,
	u32 val)
{
	irq_reg_writel(val, gc->reg_base + reg);
}

static inline u32 ab_irqctl_readreg(struct irq_chip_generic *gc, u32 reg)
{
	return irq_reg_readl(gc->reg_base + reg);
}

static int tb10x_irq_set_type(struct irq_data *data, unsigned int flow_type)
{
	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(data);
	uint32_t im, mod, pol;

	im = data->mask;

	irq_gc_lock(gc);

	mod = ab_irqctl_readreg(gc, AB_IRQCTL_SRC_MODE) | im;
	pol = ab_irqctl_readreg(gc, AB_IRQCTL_SRC_POLARITY) | im;

	switch (flow_type & IRQF_TRIGGER_MASK) {
	case IRQ_TYPE_EDGE_FALLING:
		pol ^= im;
		break;
	case IRQ_TYPE_LEVEL_HIGH:
		mod ^= im;
		break;
	case IRQ_TYPE_NONE:
		flow_type = IRQ_TYPE_LEVEL_LOW;
	case IRQ_TYPE_LEVEL_LOW:
		mod ^= im;
		pol ^= im;
		break;
	case IRQ_TYPE_EDGE_RISING:
		break;
	default:
		irq_gc_unlock(gc);
		pr_err("%s: Cannot assign multiple trigger modes to IRQ %d.\n",
			__func__, data->irq);
		return -EBADR;
	}

	irqd_set_trigger_type(data, flow_type);
	irq_setup_alt_chip(data, flow_type);

	ab_irqctl_writereg(gc, AB_IRQCTL_SRC_MODE, mod);
	ab_irqctl_writereg(gc, AB_IRQCTL_SRC_POLARITY, pol);
	ab_irqctl_writereg(gc, AB_IRQCTL_INT_STATUS, im);

	irq_gc_unlock(gc);

	return IRQ_SET_MASK_OK;
}

static void tb10x_irq_cascade(unsigned int irq, struct irq_desc *desc)
{
	struct irq_domain *domain = irq_desc_get_handler_data(desc);

	generic_handle_irq(irq_find_mapping(domain, irq));
}

static int __init of_tb10x_init_irq(struct device_node *ictl,
					struct device_node *parent)
{
	int i, ret, nrirqs = of_irq_count(ictl);
	struct resource mem;
	struct irq_chip_generic *gc;
	struct irq_domain *domain;
	void __iomem *reg_base;

	if (of_address_to_resource(ictl, 0, &mem)) {
		pr_err("%s: No registers declared in DeviceTree.\n",
			ictl->name);
		return -EINVAL;
	}

	if (!request_mem_region(mem.start, resource_size(&mem),
		ictl->name)) {
		pr_err("%s: Request mem region failed.\n", ictl->name);
		return -EBUSY;
	}

	reg_base = ioremap(mem.start, resource_size(&mem));
	if (!reg_base) {
		ret = -EBUSY;
		pr_err("%s: ioremap failed.\n", ictl->name);
		goto ioremap_fail;
	}

	domain = irq_domain_add_linear(ictl, AB_IRQCTL_MAXIRQ,
					&irq_generic_chip_ops, NULL);
	if (!domain) {
		ret = -ENOMEM;
		pr_err("%s: Could not register interrupt domain.\n",
			ictl->name);
		goto irq_domain_add_fail;
	}

	ret = irq_alloc_domain_generic_chips(domain, AB_IRQCTL_MAXIRQ,
				2, ictl->name, handle_level_irq,
				IRQ_NOREQUEST, IRQ_NOPROBE,
				IRQ_GC_INIT_MASK_CACHE);
	if (ret) {
		pr_err("%s: Could not allocate generic interrupt chip.\n",
			ictl->name);
		goto gc_alloc_fail;
	}

	gc = domain->gc->gc[0];
	gc->reg_base                         = reg_base;

	gc->chip_types[0].type               = IRQ_TYPE_LEVEL_MASK;
	gc->chip_types[0].chip.irq_mask      = irq_gc_mask_clr_bit;
	gc->chip_types[0].chip.irq_unmask    = irq_gc_mask_set_bit;
	gc->chip_types[0].chip.irq_set_type  = tb10x_irq_set_type;
	gc->chip_types[0].regs.mask          = AB_IRQCTL_INT_ENABLE;

	gc->chip_types[1].type               = IRQ_TYPE_EDGE_BOTH;
	gc->chip_types[1].chip.name          = gc->chip_types[0].chip.name;
	gc->chip_types[1].chip.irq_ack       = irq_gc_ack_set_bit;
	gc->chip_types[1].chip.irq_mask      = irq_gc_mask_clr_bit;
	gc->chip_types[1].chip.irq_unmask    = irq_gc_mask_set_bit;
	gc->chip_types[1].chip.irq_set_type  = tb10x_irq_set_type;
	gc->chip_types[1].regs.ack           = AB_IRQCTL_INT_STATUS;
	gc->chip_types[1].regs.mask          = AB_IRQCTL_INT_ENABLE;
	gc->chip_types[1].handler            = handle_edge_irq;

	for (i = 0; i < nrirqs; i++) {
		unsigned int irq = irq_of_parse_and_map(ictl, i);

		irq_set_handler_data(irq, domain);
		irq_set_chained_handler(irq, tb10x_irq_cascade);
	}

	ab_irqctl_writereg(gc, AB_IRQCTL_INT_ENABLE, 0);
	ab_irqctl_writereg(gc, AB_IRQCTL_INT_MODE, 0);
	ab_irqctl_writereg(gc, AB_IRQCTL_INT_POLARITY, 0);
	ab_irqctl_writereg(gc, AB_IRQCTL_INT_STATUS, ~0UL);

	return 0;

gc_alloc_fail:
	irq_domain_remove(domain);
irq_domain_add_fail:
	iounmap(reg_base);
ioremap_fail:
	release_mem_region(mem.start, resource_size(&mem));
	return ret;
}
IRQCHIP_DECLARE(tb10x_intc, "abilis,tb10x-ictl", of_tb10x_init_irq);