1 /*
2  *  arch/arm/mach-vt8500/irq.c
3  *
4  *  Copyright (C) 2010 Alexey Charkov <alchark@gmail.com>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
19  */
20 
21 #include <linux/io.h>
22 #include <linux/irq.h>
23 #include <linux/interrupt.h>
24 
25 #include <asm/irq.h>
26 
27 #include "devices.h"
28 
29 #define VT8500_IC_DCTR		0x40		/* Destination control
30 						register, 64*u8 */
31 #define VT8500_INT_ENABLE	(1 << 3)
32 #define VT8500_TRIGGER_HIGH	(0 << 4)
33 #define VT8500_TRIGGER_RISING	(1 << 4)
34 #define VT8500_TRIGGER_FALLING	(2 << 4)
35 #define VT8500_EDGE		( VT8500_TRIGGER_RISING \
36 				| VT8500_TRIGGER_FALLING)
37 #define VT8500_IC_STATUS	0x80		/* Interrupt status, 2*u32 */
38 
39 static void __iomem *ic_regbase;
40 static void __iomem *sic_regbase;
41 
vt8500_irq_mask(unsigned int irq)42 static void vt8500_irq_mask(unsigned int irq)
43 {
44 	void __iomem *base = ic_regbase;
45 	u8 edge;
46 
47 	if (irq >= 64) {
48 		base = sic_regbase;
49 		irq -= 64;
50 	}
51 	edge = readb(base + VT8500_IC_DCTR + irq) & VT8500_EDGE;
52 	if (edge) {
53 		void __iomem *stat_reg = base + VT8500_IC_STATUS
54 						+ (irq < 32 ? 0 : 4);
55 		unsigned status = readl(stat_reg);
56 
57 		status |= (1 << (irq & 0x1f));
58 		writel(status, stat_reg);
59 	} else {
60 		u8 dctr = readb(base + VT8500_IC_DCTR + irq);
61 
62 		dctr &= ~VT8500_INT_ENABLE;
63 		writeb(dctr, base + VT8500_IC_DCTR + irq);
64 	}
65 }
66 
vt8500_irq_unmask(unsigned int irq)67 static void vt8500_irq_unmask(unsigned int irq)
68 {
69 	void __iomem *base = ic_regbase;
70 	u8 dctr;
71 
72 	if (irq >= 64) {
73 		base = sic_regbase;
74 		irq -= 64;
75 	}
76 	dctr = readb(base + VT8500_IC_DCTR + irq);
77 	dctr |= VT8500_INT_ENABLE;
78 	writeb(dctr, base + VT8500_IC_DCTR + irq);
79 }
80 
vt8500_irq_set_type(unsigned int irq,unsigned int flow_type)81 static int vt8500_irq_set_type(unsigned int irq, unsigned int flow_type)
82 {
83 	void __iomem *base = ic_regbase;
84 	unsigned int orig_irq = irq;
85 	u8 dctr;
86 
87 	if (irq >= 64) {
88 		base = sic_regbase;
89 		irq -= 64;
90 	}
91 
92 	dctr = readb(base + VT8500_IC_DCTR + irq);
93 	dctr &= ~VT8500_EDGE;
94 
95 	switch (flow_type) {
96 	case IRQF_TRIGGER_LOW:
97 		return -EINVAL;
98 	case IRQF_TRIGGER_HIGH:
99 		dctr |= VT8500_TRIGGER_HIGH;
100 		__irq_set_handler_locked(orig_irq, handle_level_irq);
101 		break;
102 	case IRQF_TRIGGER_FALLING:
103 		dctr |= VT8500_TRIGGER_FALLING;
104 		__irq_set_handler_locked(orig_irq, handle_edge_irq);
105 		break;
106 	case IRQF_TRIGGER_RISING:
107 		dctr |= VT8500_TRIGGER_RISING;
108 		__irq_set_handler_locked(orig_irq, handle_edge_irq);
109 		break;
110 	}
111 	writeb(dctr, base + VT8500_IC_DCTR + irq);
112 
113 	return 0;
114 }
115 
116 static struct irq_chip vt8500_irq_chip = {
117 	.name      = "vt8500",
118 	.ack       = vt8500_irq_mask,
119 	.mask      = vt8500_irq_mask,
120 	.unmask    = vt8500_irq_unmask,
121 	.set_type  = vt8500_irq_set_type,
122 };
123 
vt8500_init_irq(void)124 void __init vt8500_init_irq(void)
125 {
126 	unsigned int i;
127 
128 	ic_regbase = ioremap(wmt_ic_base, SZ_64K);
129 
130 	if (ic_regbase) {
131 		/* Enable rotating priority for IRQ */
132 		writel((1 << 6), ic_regbase + 0x20);
133 		writel(0, ic_regbase + 0x24);
134 
135 		for (i = 0; i < wmt_nr_irqs; i++) {
136 			/* Disable all interrupts and route them to IRQ */
137 			writeb(0x00, ic_regbase + VT8500_IC_DCTR + i);
138 
139 			irq_set_chip_and_handler(i, &vt8500_irq_chip,
140 						 handle_level_irq);
141 			set_irq_flags(i, IRQF_VALID);
142 		}
143 	} else {
144 		printk(KERN_ERR "Unable to remap the Interrupt Controller registers, not enabling IRQs!\n");
145 	}
146 }
147 
wm8505_init_irq(void)148 void __init wm8505_init_irq(void)
149 {
150 	unsigned int i;
151 
152 	ic_regbase = ioremap(wmt_ic_base, SZ_64K);
153 	sic_regbase = ioremap(wmt_sic_base, SZ_64K);
154 
155 	if (ic_regbase && sic_regbase) {
156 		/* Enable rotating priority for IRQ */
157 		writel((1 << 6), ic_regbase + 0x20);
158 		writel(0, ic_regbase + 0x24);
159 		writel((1 << 6), sic_regbase + 0x20);
160 		writel(0, sic_regbase + 0x24);
161 
162 		for (i = 0; i < wmt_nr_irqs; i++) {
163 			/* Disable all interrupts and route them to IRQ */
164 			if (i < 64)
165 				writeb(0x00, ic_regbase + VT8500_IC_DCTR + i);
166 			else
167 				writeb(0x00, sic_regbase + VT8500_IC_DCTR
168 								+ i - 64);
169 
170 			irq_set_chip_and_handler(i, &vt8500_irq_chip,
171 						 handle_level_irq);
172 			set_irq_flags(i, IRQF_VALID);
173 		}
174 	} else {
175 		printk(KERN_ERR "Unable to remap the Interrupt Controller registers, not enabling IRQs!\n");
176 	}
177 }
178