tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * TI LP8788 MFD - interrupt handler
3 *
4 * Copyright 2012 Texas Instruments
5 *
6 * Author: Milo(Woogyom) Kim <milo.kim@ti.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 *
12 */
13
14#include <linux/delay.h>
15#include <linux/err.h>
16#include <linux/interrupt.h>
17#include <linux/irq.h>
18#include <linux/irqdomain.h>
19#include <linux/device.h>
20#include <linux/mfd/lp8788.h>
21#include <linux/module.h>
22#include <linux/slab.h>
23
24/* register address */
25#define LP8788_INT_1 0x00
26#define LP8788_INTEN_1 0x03
27
28#define BASE_INTEN_ADDR LP8788_INTEN_1
29#define SIZE_REG 8
30#define NUM_REGS 3
31
32/*
33 * struct lp8788_irq_data
34 * @lp : used for accessing to lp8788 registers
35 * @irq_lock : mutex for enabling/disabling the interrupt
36 * @domain : IRQ domain for handling nested interrupt
37 * @enabled : status of enabled interrupt
38 */
39struct lp8788_irq_data {
40 struct lp8788 *lp;
41 struct mutex irq_lock;
42 struct irq_domain *domain;
43 int enabled[LP8788_INT_MAX];
44};
45
46static inline u8 _irq_to_addr(enum lp8788_int_id id)
47{
48 return id / SIZE_REG;
49}
50
51static inline u8 _irq_to_enable_addr(enum lp8788_int_id id)
52{
53 return _irq_to_addr(id) + BASE_INTEN_ADDR;
54}
55
56static inline u8 _irq_to_mask(enum lp8788_int_id id)
57{
58 return 1 << (id % SIZE_REG);
59}
60
61static inline u8 _irq_to_val(enum lp8788_int_id id, int enable)
62{
63 return enable << (id % SIZE_REG);
64}
65
66static void lp8788_irq_enable(struct irq_data *data)
67{
68 struct lp8788_irq_data *irqd = irq_data_get_irq_chip_data(data);
69 irqd->enabled[data->hwirq] = 1;
70}
71
72static void lp8788_irq_disable(struct irq_data *data)
73{
74 struct lp8788_irq_data *irqd = irq_data_get_irq_chip_data(data);
75 irqd->enabled[data->hwirq] = 0;
76}
77
78static void lp8788_irq_bus_lock(struct irq_data *data)
79{
80 struct lp8788_irq_data *irqd = irq_data_get_irq_chip_data(data);
81
82 mutex_lock(&irqd->irq_lock);
83}
84
85static void lp8788_irq_bus_sync_unlock(struct irq_data *data)
86{
87 struct lp8788_irq_data *irqd = irq_data_get_irq_chip_data(data);
88 enum lp8788_int_id irq = data->hwirq;
89 u8 addr, mask, val;
90
91 addr = _irq_to_enable_addr(irq);
92 mask = _irq_to_mask(irq);
93 val = _irq_to_val(irq, irqd->enabled[irq]);
94
95 lp8788_update_bits(irqd->lp, addr, mask, val);
96
97 mutex_unlock(&irqd->irq_lock);
98}
99
100static struct irq_chip lp8788_irq_chip = {
101 .name = "lp8788",
102 .irq_enable = lp8788_irq_enable,
103 .irq_disable = lp8788_irq_disable,
104 .irq_bus_lock = lp8788_irq_bus_lock,
105 .irq_bus_sync_unlock = lp8788_irq_bus_sync_unlock,
106};
107
108static irqreturn_t lp8788_irq_handler(int irq, void *ptr)
109{
110 struct lp8788_irq_data *irqd = ptr;
111 struct lp8788 *lp = irqd->lp;
112 u8 status[NUM_REGS], addr, mask;
113 bool handled;
114 int i;
115
116 if (lp8788_read_multi_bytes(lp, LP8788_INT_1, status, NUM_REGS))
117 return IRQ_NONE;
118
119 for (i = 0 ; i < LP8788_INT_MAX ; i++) {
120 addr = _irq_to_addr(i);
121 mask = _irq_to_mask(i);
122
123 /* reporting only if the irq is enabled */
124 if (status[addr] & mask) {
125 handle_nested_irq(irq_find_mapping(irqd->domain, i));
126 handled = true;
127 }
128 }
129
130 return handled ? IRQ_HANDLED : IRQ_NONE;
131}
132
133static int lp8788_irq_map(struct irq_domain *d, unsigned int virq,
134 irq_hw_number_t hwirq)
135{
136 struct lp8788_irq_data *irqd = d->host_data;
137 struct irq_chip *chip = &lp8788_irq_chip;
138
139 irq_set_chip_data(virq, irqd);
140 irq_set_chip_and_handler(virq, chip, handle_edge_irq);
141 irq_set_nested_thread(virq, 1);
142
143#ifdef CONFIG_ARM
144 set_irq_flags(virq, IRQF_VALID);
145#else
146 irq_set_noprobe(virq);
147#endif
148
149 return 0;
150}
151
152static struct irq_domain_ops lp8788_domain_ops = {
153 .map = lp8788_irq_map,
154};
155
156int lp8788_irq_init(struct lp8788 *lp, int irq)
157{
158 struct lp8788_irq_data *irqd;
159 int ret;
160
161 if (irq <= 0) {
162 dev_warn(lp->dev, "invalid irq number: %d\n", irq);
163 return 0;
164 }
165
166 irqd = devm_kzalloc(lp->dev, sizeof(*irqd), GFP_KERNEL);
167 if (!irqd)
168 return -ENOMEM;
169
170 irqd->lp = lp;
171 irqd->domain = irq_domain_add_linear(lp->dev->of_node, LP8788_INT_MAX,
172 &lp8788_domain_ops, irqd);
173 if (!irqd->domain) {
174 dev_err(lp->dev, "failed to add irq domain err\n");
175 return -EINVAL;
176 }
177
178 lp->irqdm = irqd->domain;
179 mutex_init(&irqd->irq_lock);
180
181 ret = request_threaded_irq(irq, NULL, lp8788_irq_handler,
182 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
183 "lp8788-irq", irqd);
184 if (ret) {
185 dev_err(lp->dev, "failed to create a thread for IRQ_N\n");
186 return ret;
187 }
188
189 lp->irq = irq;
190
191 return 0;
192}
193
194void lp8788_irq_exit(struct lp8788 *lp)
195{
196 if (lp->irq)
197 free_irq(lp->irq, lp->irqdm);
198}