V4L/DVB (6715): ivtv: Remove unnecessary register update
[linux-2.6/verdex.git] / drivers / parisc / gsc.c
blob1b3e3fd12d95882492c6bd86ab9f367eb925bbb8
1 /*
2 * Interrupt management for most GSC and related devices.
4 * (c) Copyright 1999 Alex deVries for The Puffin Group
5 * (c) Copyright 1999 Grant Grundler for Hewlett-Packard
6 * (c) Copyright 1999 Matthew Wilcox
7 * (c) Copyright 2000 Helge Deller
8 * (c) Copyright 2001 Matthew Wilcox for Hewlett-Packard
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
16 #include <linux/bitops.h>
17 #include <linux/errno.h>
18 #include <linux/init.h>
19 #include <linux/interrupt.h>
20 #include <linux/ioport.h>
21 #include <linux/module.h>
22 #include <linux/slab.h>
23 #include <linux/types.h>
25 #include <asm/hardware.h>
26 #include <asm/io.h>
28 #include "gsc.h"
30 #undef DEBUG
32 #ifdef DEBUG
33 #define DEBPRINTK printk
34 #else
35 #define DEBPRINTK(x,...)
36 #endif
38 int gsc_alloc_irq(struct gsc_irq *i)
40 int irq = txn_alloc_irq(GSC_EIM_WIDTH);
41 if (irq < 0) {
42 printk("cannot get irq\n");
43 return irq;
46 i->txn_addr = txn_alloc_addr(irq);
47 i->txn_data = txn_alloc_data(irq);
48 i->irq = irq;
50 return irq;
53 int gsc_claim_irq(struct gsc_irq *i, int irq)
55 int c = irq;
57 irq += CPU_IRQ_BASE; /* virtualize the IRQ first */
59 irq = txn_claim_irq(irq);
60 if (irq < 0) {
61 printk("cannot claim irq %d\n", c);
62 return irq;
65 i->txn_addr = txn_alloc_addr(irq);
66 i->txn_data = txn_alloc_data(irq);
67 i->irq = irq;
69 return irq;
72 EXPORT_SYMBOL(gsc_alloc_irq);
73 EXPORT_SYMBOL(gsc_claim_irq);
75 /* Common interrupt demultiplexer used by Asp, Lasi & Wax. */
76 irqreturn_t gsc_asic_intr(int gsc_asic_irq, void *dev)
78 unsigned long irr;
79 struct gsc_asic *gsc_asic = dev;
81 irr = gsc_readl(gsc_asic->hpa + OFFSET_IRR);
82 if (irr == 0)
83 return IRQ_NONE;
85 DEBPRINTK("%s intr, mask=0x%x\n", gsc_asic->name, irr);
87 do {
88 int local_irq = __ffs(irr);
89 unsigned int irq = gsc_asic->global_irq[local_irq];
90 __do_IRQ(irq);
91 irr &= ~(1 << local_irq);
92 } while (irr);
94 return IRQ_HANDLED;
97 int gsc_find_local_irq(unsigned int irq, int *global_irqs, int limit)
99 int local_irq;
101 for (local_irq = 0; local_irq < limit; local_irq++) {
102 if (global_irqs[local_irq] == irq)
103 return local_irq;
106 return NO_IRQ;
109 static void gsc_asic_disable_irq(unsigned int irq)
111 struct gsc_asic *irq_dev = irq_desc[irq].chip_data;
112 int local_irq = gsc_find_local_irq(irq, irq_dev->global_irq, 32);
113 u32 imr;
115 DEBPRINTK(KERN_DEBUG "%s(%d) %s: IMR 0x%x\n", __FUNCTION__, irq,
116 irq_dev->name, imr);
118 /* Disable the IRQ line by clearing the bit in the IMR */
119 imr = gsc_readl(irq_dev->hpa + OFFSET_IMR);
120 imr &= ~(1 << local_irq);
121 gsc_writel(imr, irq_dev->hpa + OFFSET_IMR);
124 static void gsc_asic_enable_irq(unsigned int irq)
126 struct gsc_asic *irq_dev = irq_desc[irq].chip_data;
127 int local_irq = gsc_find_local_irq(irq, irq_dev->global_irq, 32);
128 u32 imr;
130 DEBPRINTK(KERN_DEBUG "%s(%d) %s: IMR 0x%x\n", __FUNCTION__, irq,
131 irq_dev->name, imr);
133 /* Enable the IRQ line by setting the bit in the IMR */
134 imr = gsc_readl(irq_dev->hpa + OFFSET_IMR);
135 imr |= 1 << local_irq;
136 gsc_writel(imr, irq_dev->hpa + OFFSET_IMR);
138 * FIXME: read IPR to make sure the IRQ isn't already pending.
139 * If so, we need to read IRR and manually call do_irq().
143 static unsigned int gsc_asic_startup_irq(unsigned int irq)
145 gsc_asic_enable_irq(irq);
146 return 0;
149 static struct hw_interrupt_type gsc_asic_interrupt_type = {
150 .typename = "GSC-ASIC",
151 .startup = gsc_asic_startup_irq,
152 .shutdown = gsc_asic_disable_irq,
153 .enable = gsc_asic_enable_irq,
154 .disable = gsc_asic_disable_irq,
155 .ack = no_ack_irq,
156 .end = no_end_irq,
159 int gsc_assign_irq(struct hw_interrupt_type *type, void *data)
161 static int irq = GSC_IRQ_BASE;
163 if (irq > GSC_IRQ_MAX)
164 return NO_IRQ;
166 irq_desc[irq].chip = type;
167 irq_desc[irq].chip_data = data;
168 return irq++;
171 void gsc_asic_assign_irq(struct gsc_asic *asic, int local_irq, int *irqp)
173 int irq = asic->global_irq[local_irq];
175 if (irq <= 0) {
176 irq = gsc_assign_irq(&gsc_asic_interrupt_type, asic);
177 if (irq == NO_IRQ)
178 return;
180 asic->global_irq[local_irq] = irq;
182 *irqp = irq;
185 static struct device *next_device(struct klist_iter *i)
187 struct klist_node * n = klist_next(i);
188 return n ? container_of(n, struct device, knode_parent) : NULL;
191 void gsc_fixup_irqs(struct parisc_device *parent, void *ctrl,
192 void (*choose_irq)(struct parisc_device *, void *))
194 struct device *dev;
195 struct klist_iter i;
197 klist_iter_init(&parent->dev.klist_children, &i);
198 while ((dev = next_device(&i))) {
199 struct parisc_device *padev = to_parisc_device(dev);
201 /* work-around for 715/64 and others which have parent
202 at path [5] and children at path [5/0/x] */
203 if (padev->id.hw_type == HPHW_FAULTY)
204 return gsc_fixup_irqs(padev, ctrl, choose_irq);
205 choose_irq(padev, ctrl);
207 klist_iter_exit(&i);
210 int gsc_common_setup(struct parisc_device *parent, struct gsc_asic *gsc_asic)
212 struct resource *res;
213 int i;
215 gsc_asic->gsc = parent;
217 /* Initialise local irq -> global irq mapping */
218 for (i = 0; i < 32; i++) {
219 gsc_asic->global_irq[i] = NO_IRQ;
222 /* allocate resource region */
223 res = request_mem_region(gsc_asic->hpa, 0x100000, gsc_asic->name);
224 if (res) {
225 res->flags = IORESOURCE_MEM; /* do not mark it busy ! */
228 #if 0
229 printk(KERN_WARNING "%s IRQ %d EIM 0x%x", gsc_asic->name,
230 parent->irq, gsc_asic->eim);
231 if (gsc_readl(gsc_asic->hpa + OFFSET_IMR))
232 printk(" IMR is non-zero! (0x%x)",
233 gsc_readl(gsc_asic->hpa + OFFSET_IMR));
234 printk("\n");
235 #endif
237 return 0;
240 extern struct parisc_driver lasi_driver;
241 extern struct parisc_driver asp_driver;
242 extern struct parisc_driver wax_driver;
244 void __init gsc_init(void)
246 #ifdef CONFIG_GSC_LASI
247 register_parisc_driver(&lasi_driver);
248 register_parisc_driver(&asp_driver);
249 #endif
250 #ifdef CONFIG_GSC_WAX
251 register_parisc_driver(&wax_driver);
252 #endif