1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * TI LP8788 MFD - interrupt handler
4 *
5 * Copyright 2012 Texas Instruments
6 *
7 * Author: Milo(Woogyom) Kim <milo.kim@ti.com>
8 */
9
10 #include <linux/delay.h>
11 #include <linux/err.h>
12 #include <linux/interrupt.h>
13 #include <linux/irq.h>
14 #include <linux/irqdomain.h>
15 #include <linux/device.h>
16 #include <linux/mfd/lp8788.h>
17 #include <linux/module.h>
18 #include <linux/slab.h>
19
20 /* register address */
21 #define LP8788_INT_1 0x00
22 #define LP8788_INTEN_1 0x03
23
24 #define BASE_INTEN_ADDR LP8788_INTEN_1
25 #define SIZE_REG 8
26 #define NUM_REGS 3
27
28 /*
29 * struct lp8788_irq_data
30 * @lp : used for accessing to lp8788 registers
31 * @irq_lock : mutex for enabling/disabling the interrupt
32 * @domain : IRQ domain for handling nested interrupt
33 * @enabled : status of enabled interrupt
34 */
35 struct lp8788_irq_data {
36 struct lp8788 *lp;
37 struct mutex irq_lock;
38 struct irq_domain *domain;
39 int enabled[LP8788_INT_MAX];
40 };
41
_irq_to_addr(enum lp8788_int_id id)42 static inline u8 _irq_to_addr(enum lp8788_int_id id)
43 {
44 return id / SIZE_REG;
45 }
46
_irq_to_enable_addr(enum lp8788_int_id id)47 static inline u8 _irq_to_enable_addr(enum lp8788_int_id id)
48 {
49 return _irq_to_addr(id) + BASE_INTEN_ADDR;
50 }
51
_irq_to_mask(enum lp8788_int_id id)52 static inline u8 _irq_to_mask(enum lp8788_int_id id)
53 {
54 return 1 << (id % SIZE_REG);
55 }
56
_irq_to_val(enum lp8788_int_id id,int enable)57 static inline u8 _irq_to_val(enum lp8788_int_id id, int enable)
58 {
59 return enable << (id % SIZE_REG);
60 }
61
lp8788_irq_enable(struct irq_data * data)62 static void lp8788_irq_enable(struct irq_data *data)
63 {
64 struct lp8788_irq_data *irqd = irq_data_get_irq_chip_data(data);
65
66 irqd->enabled[data->hwirq] = 1;
67 }
68
lp8788_irq_disable(struct irq_data * data)69 static void lp8788_irq_disable(struct irq_data *data)
70 {
71 struct lp8788_irq_data *irqd = irq_data_get_irq_chip_data(data);
72
73 irqd->enabled[data->hwirq] = 0;
74 }
75
lp8788_irq_bus_lock(struct irq_data * data)76 static void lp8788_irq_bus_lock(struct irq_data *data)
77 {
78 struct lp8788_irq_data *irqd = irq_data_get_irq_chip_data(data);
79
80 mutex_lock(&irqd->irq_lock);
81 }
82
lp8788_irq_bus_sync_unlock(struct irq_data * data)83 static void lp8788_irq_bus_sync_unlock(struct irq_data *data)
84 {
85 struct lp8788_irq_data *irqd = irq_data_get_irq_chip_data(data);
86 enum lp8788_int_id irq = data->hwirq;
87 u8 addr, mask, val;
88
89 addr = _irq_to_enable_addr(irq);
90 mask = _irq_to_mask(irq);
91 val = _irq_to_val(irq, irqd->enabled[irq]);
92
93 lp8788_update_bits(irqd->lp, addr, mask, val);
94
95 mutex_unlock(&irqd->irq_lock);
96 }
97
98 static struct irq_chip lp8788_irq_chip = {
99 .name = "lp8788",
100 .irq_enable = lp8788_irq_enable,
101 .irq_disable = lp8788_irq_disable,
102 .irq_bus_lock = lp8788_irq_bus_lock,
103 .irq_bus_sync_unlock = lp8788_irq_bus_sync_unlock,
104 };
105
lp8788_irq_handler(int irq,void * ptr)106 static irqreturn_t lp8788_irq_handler(int irq, void *ptr)
107 {
108 struct lp8788_irq_data *irqd = ptr;
109 struct lp8788 *lp = irqd->lp;
110 u8 status[NUM_REGS], addr, mask;
111 bool handled = false;
112 int i;
113
114 if (lp8788_read_multi_bytes(lp, LP8788_INT_1, status, NUM_REGS))
115 return IRQ_NONE;
116
117 for (i = 0 ; i < LP8788_INT_MAX ; i++) {
118 addr = _irq_to_addr(i);
119 mask = _irq_to_mask(i);
120
121 /* reporting only if the irq is enabled */
122 if (status[addr] & mask) {
123 handle_nested_irq(irq_find_mapping(irqd->domain, i));
124 handled = true;
125 }
126 }
127
128 return handled ? IRQ_HANDLED : IRQ_NONE;
129 }
130
lp8788_irq_map(struct irq_domain * d,unsigned int virq,irq_hw_number_t hwirq)131 static int lp8788_irq_map(struct irq_domain *d, unsigned int virq,
132 irq_hw_number_t hwirq)
133 {
134 struct lp8788_irq_data *irqd = d->host_data;
135 struct irq_chip *chip = &lp8788_irq_chip;
136
137 irq_set_chip_data(virq, irqd);
138 irq_set_chip_and_handler(virq, chip, handle_edge_irq);
139 irq_set_nested_thread(virq, 1);
140 irq_set_noprobe(virq);
141
142 return 0;
143 }
144
145 static const struct irq_domain_ops lp8788_domain_ops = {
146 .map = lp8788_irq_map,
147 };
148
lp8788_irq_init(struct lp8788 * lp,int irq)149 int lp8788_irq_init(struct lp8788 *lp, int irq)
150 {
151 struct lp8788_irq_data *irqd;
152 int ret;
153
154 if (irq <= 0) {
155 dev_warn(lp->dev, "invalid irq number: %d\n", irq);
156 return 0;
157 }
158
159 irqd = devm_kzalloc(lp->dev, sizeof(*irqd), GFP_KERNEL);
160 if (!irqd)
161 return -ENOMEM;
162
163 irqd->lp = lp;
164 irqd->domain = irq_domain_add_linear(lp->dev->of_node, LP8788_INT_MAX,
165 &lp8788_domain_ops, irqd);
166 if (!irqd->domain) {
167 dev_err(lp->dev, "failed to add irq domain err\n");
168 return -EINVAL;
169 }
170
171 lp->irqdm = irqd->domain;
172 mutex_init(&irqd->irq_lock);
173
174 ret = request_threaded_irq(irq, NULL, lp8788_irq_handler,
175 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
176 "lp8788-irq", irqd);
177 if (ret) {
178 dev_err(lp->dev, "failed to create a thread for IRQ_N\n");
179 return ret;
180 }
181
182 lp->irq = irq;
183
184 return 0;
185 }
186
lp8788_irq_exit(struct lp8788 * lp)187 void lp8788_irq_exit(struct lp8788 *lp)
188 {
189 if (lp->irq)
190 free_irq(lp->irq, lp->irqdm);
191 }
192