a56be931551c9ac7ee34e546a18891e8a2b6549d
[linux-2.6.git] / drivers / mfd / tps65910-irq.c
1 /*
2  * tps65910-irq.c  --  TI TPS6591x
3  *
4  * Copyright 2010 Texas Instruments Inc.
5  *
6  * Author: Graeme Gregory <gg@slimlogic.co.uk>
7  * Author: Jorge Eduardo Candelaria <jedu@slimlogic.co.uk>
8  *
9  *  This program is free software; you can redistribute it and/or modify it
10  *  under  the terms of the GNU General  Public License as published by the
11  *  Free Software Foundation;  either version 2 of the License, or (at your
12  *  option) any later version.
13  *
14  */
15
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/init.h>
19 #include <linux/bug.h>
20 #include <linux/device.h>
21 #include <linux/interrupt.h>
22 #include <linux/irq.h>
23 #include <linux/gpio.h>
24 #include <linux/mfd/tps65910.h>
25
26 static inline int irq_to_tps65910_irq(struct tps65910 *tps65910,
27                                                         int irq)
28 {
29         return (irq - tps65910->irq_base);
30 }
31
32 /*
33  * This is a threaded IRQ handler so can access I2C/SPI.  Since all
34  * interrupts are clear on read the IRQ line will be reasserted and
35  * the physical IRQ will be handled again if another interrupt is
36  * asserted while we run - in the normal course of events this is a
37  * rare occurrence so we save I2C/SPI reads.  We're also assuming that
38  * it's rare to get lots of interrupts firing simultaneously so try to
39  * minimise I/O.
40  */
41 static irqreturn_t tps65910_irq(int irq, void *irq_data)
42 {
43         struct tps65910 *tps65910 = irq_data;
44         u32 irq_sts;
45         u32 irq_mask;
46         u8 reg;
47         int i;
48
49         tps65910->read(tps65910, TPS65910_INT_STS, 1, &reg);
50         irq_sts = reg;
51         tps65910->read(tps65910, TPS65910_INT_STS2, 1, &reg);
52         irq_sts |= reg << 8;
53         switch (tps65910_chip_id(tps65910)) {
54         case TPS65911:
55                 tps65910->read(tps65910, TPS65910_INT_STS3, 1, &reg);
56                 irq_sts |= reg << 16;
57         }
58
59         tps65910->read(tps65910, TPS65910_INT_MSK, 1, &reg);
60         irq_mask = reg;
61         tps65910->read(tps65910, TPS65910_INT_MSK2, 1, &reg);
62         irq_mask |= reg << 8;
63         switch (tps65910_chip_id(tps65910)) {
64         case TPS65911:
65                 tps65910->read(tps65910, TPS65910_INT_MSK3, 1, &reg);
66                 irq_mask |= reg << 16;
67         }
68
69         irq_sts &= ~irq_mask;
70
71         if (!irq_sts)
72                 return IRQ_NONE;
73
74         for (i = 0; i < tps65910->irq_num; i++) {
75
76                 if (!(irq_sts & (1 << i)))
77                         continue;
78
79                 handle_nested_irq(tps65910->irq_base + i);
80         }
81
82         /* Write the STS register back to clear IRQs we handled */
83         reg = irq_sts & 0xFF;
84         irq_sts >>= 8;
85         tps65910->write(tps65910, TPS65910_INT_STS, 1, &reg);
86         reg = irq_sts & 0xFF;
87         tps65910->write(tps65910, TPS65910_INT_STS2, 1, &reg);
88         switch (tps65910_chip_id(tps65910)) {
89         case TPS65911:
90                 reg = irq_sts >> 8;
91                 tps65910->write(tps65910, TPS65910_INT_STS3, 1, &reg);
92         }
93
94         return IRQ_HANDLED;
95 }
96
97 static void tps65910_irq_lock(struct irq_data *data)
98 {
99         struct tps65910 *tps65910 = irq_data_get_irq_chip_data(data);
100
101         mutex_lock(&tps65910->irq_lock);
102 }
103
104 static void tps65910_irq_sync_unlock(struct irq_data *data)
105 {
106         struct tps65910 *tps65910 = irq_data_get_irq_chip_data(data);
107         u32 reg_mask;
108         u8 reg;
109
110         tps65910->read(tps65910, TPS65910_INT_MSK, 1, &reg);
111         reg_mask = reg;
112         tps65910->read(tps65910, TPS65910_INT_MSK2, 1, &reg);
113         reg_mask |= reg << 8;
114         switch (tps65910_chip_id(tps65910)) {
115         case TPS65911:
116                 tps65910->read(tps65910, TPS65910_INT_MSK3, 1, &reg);
117                 reg_mask |= reg << 16;
118         }
119
120         if (tps65910->irq_mask != reg_mask) {
121                 reg = tps65910->irq_mask & 0xFF;
122                 tps65910->write(tps65910, TPS65910_INT_MSK, 1, &reg);
123                 reg = tps65910->irq_mask >> 8 & 0xFF;
124                 tps65910->write(tps65910, TPS65910_INT_MSK2, 1, &reg);
125                 switch (tps65910_chip_id(tps65910)) {
126                 case TPS65911:
127                         reg = tps65910->irq_mask >> 16;
128                         tps65910->write(tps65910, TPS65910_INT_MSK3, 1, &reg);
129                 }
130         }
131         mutex_unlock(&tps65910->irq_lock);
132 }
133
134 static void tps65910_irq_enable(struct irq_data *data)
135 {
136         struct tps65910 *tps65910 = irq_data_get_irq_chip_data(data);
137
138         tps65910->irq_mask &= ~( 1 << irq_to_tps65910_irq(tps65910, data->irq));
139 }
140
141 static void tps65910_irq_disable(struct irq_data *data)
142 {
143         struct tps65910 *tps65910 = irq_data_get_irq_chip_data(data);
144
145         tps65910->irq_mask |= ( 1 << irq_to_tps65910_irq(tps65910, data->irq));
146 }
147
148 static struct irq_chip tps65910_irq_chip = {
149         .name = "tps65910",
150         .irq_bus_lock = tps65910_irq_lock,
151         .irq_bus_sync_unlock = tps65910_irq_sync_unlock,
152         .irq_disable = tps65910_irq_disable,
153         .irq_enable = tps65910_irq_enable,
154 };
155
156 int tps65910_irq_init(struct tps65910 *tps65910, int irq,
157                     struct tps65910_platform_data *pdata)
158 {
159         int ret, cur_irq;
160         int flags = IRQF_ONESHOT;
161
162         if (!irq) {
163                 dev_warn(tps65910->dev, "No interrupt support, no core IRQ\n");
164                 return -EINVAL;
165         }
166
167         if (!pdata || !pdata->irq_base) {
168                 dev_warn(tps65910->dev, "No interrupt support, no IRQ base\n");
169                 return -EINVAL;
170         }
171
172         tps65910->irq_mask = 0xFFFFFF;
173
174         mutex_init(&tps65910->irq_lock);
175         tps65910->chip_irq = irq;
176         tps65910->irq_base = pdata->irq_base;
177
178         switch (tps65910_chip_id(tps65910)) {
179         case TPS65910:
180                 tps65910->irq_num = TPS65910_NUM_IRQ;
181                 break;
182         case TPS65911:
183                 tps65910->irq_num = TPS65911_NUM_IRQ;
184                 break;
185         }
186
187         /* Register with genirq */
188         for (cur_irq = tps65910->irq_base;
189              cur_irq < tps65910->irq_num + tps65910->irq_base;
190              cur_irq++) {
191                 irq_set_chip_data(cur_irq, tps65910);
192                 irq_set_chip_and_handler(cur_irq, &tps65910_irq_chip,
193                                          handle_edge_irq);
194                 irq_set_nested_thread(cur_irq, 1);
195
196                 /* ARM needs us to explicitly flag the IRQ as valid
197                  * and will set them noprobe when we do so. */
198 #ifdef CONFIG_ARM
199                 set_irq_flags(cur_irq, IRQF_VALID);
200 #else
201                 irq_set_noprobe(cur_irq);
202 #endif
203         }
204
205         ret = request_threaded_irq(irq, NULL, tps65910_irq, flags,
206                                    "tps65910", tps65910);
207
208         irq_set_irq_type(irq, IRQ_TYPE_LEVEL_LOW);
209
210         if (ret != 0)
211                 dev_err(tps65910->dev, "Failed to request IRQ: %d\n", ret);
212
213         return ret;
214 }
215
216 int tps65910_irq_exit(struct tps65910 *tps65910)
217 {
218         free_irq(tps65910->chip_irq, tps65910);
219         return 0;
220 }