Merge git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-2.6.18
[linux-2.6] / arch / arm / mach-at91rm9200 / irq.c
1 /*
2  * linux/arch/arm/mach-at91rm9200/irq.c
3  *
4  *  Copyright (C) 2004 SAN People
5  *  Copyright (C) 2004 ATMEL
6  *  Copyright (C) Rick Bronson
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 as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
21  */
22
23 #include <linux/init.h>
24 #include <linux/module.h>
25 #include <linux/mm.h>
26 #include <linux/types.h>
27
28 #include <asm/hardware.h>
29 #include <asm/irq.h>
30 #include <asm/mach-types.h>
31 #include <asm/setup.h>
32
33 #include <asm/mach/arch.h>
34 #include <asm/mach/irq.h>
35 #include <asm/mach/map.h>
36
37 #include "generic.h"
38
39
40 static void at91_aic_mask_irq(unsigned int irq)
41 {
42         /* Disable interrupt on AIC */
43         at91_sys_write(AT91_AIC_IDCR, 1 << irq);
44 }
45
46 static void at91_aic_unmask_irq(unsigned int irq)
47 {
48         /* Enable interrupt on AIC */
49         at91_sys_write(AT91_AIC_IECR, 1 << irq);
50 }
51
52 static int at91_aic_set_type(unsigned irq, unsigned type)
53 {
54         unsigned int smr, srctype;
55
56         switch (type) {
57         case IRQT_HIGH:
58                 srctype = AT91_AIC_SRCTYPE_HIGH;
59                 break;
60         case IRQT_RISING:
61                 srctype = AT91_AIC_SRCTYPE_RISING;
62                 break;
63         case IRQT_LOW:
64                 if ((irq > AT91_ID_FIQ) && (irq < AT91_ID_IRQ0))        /* only supported on external interrupts */
65                         return -EINVAL;
66                 srctype = AT91_AIC_SRCTYPE_LOW;
67                 break;
68         case IRQT_FALLING:
69                 if ((irq > AT91_ID_FIQ) && (irq < AT91_ID_IRQ0))        /* only supported on external interrupts */
70                         return -EINVAL;
71                 srctype = AT91_AIC_SRCTYPE_FALLING;
72                 break;
73         default:
74                 return -EINVAL;
75         }
76
77         smr = at91_sys_read(AT91_AIC_SMR(irq)) & ~AT91_AIC_SRCTYPE;
78         at91_sys_write(AT91_AIC_SMR(irq), smr | srctype);
79         return 0;
80 }
81
82 #ifdef CONFIG_PM
83
84 static u32 wakeups;
85 static u32 backups;
86
87 static int at91_aic_set_wake(unsigned irq, unsigned value)
88 {
89         if (unlikely(irq >= 32))
90                 return -EINVAL;
91
92         if (value)
93                 wakeups |= (1 << irq);
94         else
95                 wakeups &= ~(1 << irq);
96
97         return 0;
98 }
99
100 void at91_irq_suspend(void)
101 {
102         backups = at91_sys_read(AT91_AIC_IMR);
103         at91_sys_write(AT91_AIC_IDCR, backups);
104         at91_sys_write(AT91_AIC_IECR, wakeups);
105 }
106
107 void at91_irq_resume(void)
108 {
109         at91_sys_write(AT91_AIC_IDCR, wakeups);
110         at91_sys_write(AT91_AIC_IECR, backups);
111 }
112
113 #else
114 #define at91_aic_set_wake       NULL
115 #endif
116
117 static struct irq_chip at91_aic_chip = {
118         .name           = "AIC",
119         .ack            = at91_aic_mask_irq,
120         .mask           = at91_aic_mask_irq,
121         .unmask         = at91_aic_unmask_irq,
122         .set_type       = at91_aic_set_type,
123         .set_wake       = at91_aic_set_wake,
124 };
125
126 /*
127  * Initialize the AIC interrupt controller.
128  */
129 void __init at91_aic_init(unsigned int priority[NR_AIC_IRQS])
130 {
131         unsigned int i;
132
133         /*
134          * The IVR is used by macro get_irqnr_and_base to read and verify.
135          * The irq number is NR_AIC_IRQS when a spurious interrupt has occurred.
136          */
137         for (i = 0; i < NR_AIC_IRQS; i++) {
138                 /* Put irq number in Source Vector Register: */
139                 at91_sys_write(AT91_AIC_SVR(i), i);
140                 /* Active Low interrupt, with the specified priority */
141                 at91_sys_write(AT91_AIC_SMR(i), AT91_AIC_SRCTYPE_LOW | priority[i]);
142
143                 set_irq_chip(i, &at91_aic_chip);
144                 set_irq_handler(i, do_level_IRQ);
145                 set_irq_flags(i, IRQF_VALID | IRQF_PROBE);
146
147                 /* Perform 8 End Of Interrupt Command to make sure AIC will not Lock out nIRQ */
148                 if (i < 8)
149                         at91_sys_write(AT91_AIC_EOICR, 0);
150         }
151
152         /*
153          * Spurious Interrupt ID in Spurious Vector Register is NR_AIC_IRQS
154          * When there is no current interrupt, the IRQ Vector Register reads the value stored in AIC_SPU
155          */
156         at91_sys_write(AT91_AIC_SPU, NR_AIC_IRQS);
157
158         /* No debugging in AIC: Debug (Protect) Control Register */
159         at91_sys_write(AT91_AIC_DCR, 0);
160
161         /* Disable and clear all interrupts initially */
162         at91_sys_write(AT91_AIC_IDCR, 0xFFFFFFFF);
163         at91_sys_write(AT91_AIC_ICCR, 0xFFFFFFFF);
164 }