mfd: wm8350-i2c: Make sure the i2c regmap functions are compiled
[linux/fpc-iii.git] / drivers / of / irq.c
blob1752988d6aa80224ced68ab6e62744c77e8ab4be
1 /*
2 * Derived from arch/i386/kernel/irq.c
3 * Copyright (C) 1992 Linus Torvalds
4 * Adapted from arch/i386 by Gary Thomas
5 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
6 * Updated and modified by Cort Dougan <cort@fsmlabs.com>
7 * Copyright (C) 1996-2001 Cort Dougan
8 * Adapted for Power Macintosh by Paul Mackerras
9 * Copyright (C) 1996 Paul Mackerras (paulus@cs.anu.edu.au)
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License
13 * as published by the Free Software Foundation; either version
14 * 2 of the License, or (at your option) any later version.
16 * This file contains the code used to make IRQ descriptions in the
17 * device tree to actual irq numbers on an interrupt controller
18 * driver.
21 #include <linux/errno.h>
22 #include <linux/list.h>
23 #include <linux/module.h>
24 #include <linux/of.h>
25 #include <linux/of_irq.h>
26 #include <linux/string.h>
27 #include <linux/slab.h>
29 /**
30 * irq_of_parse_and_map - Parse and map an interrupt into linux virq space
31 * @dev: Device node of the device whose interrupt is to be mapped
32 * @index: Index of the interrupt to map
34 * This function is a wrapper that chains of_irq_map_one() and
35 * irq_create_of_mapping() to make things easier to callers
37 unsigned int irq_of_parse_and_map(struct device_node *dev, int index)
39 struct of_irq oirq;
41 if (of_irq_map_one(dev, index, &oirq))
42 return 0;
44 return irq_create_of_mapping(oirq.controller, oirq.specifier,
45 oirq.size);
47 EXPORT_SYMBOL_GPL(irq_of_parse_and_map);
49 /**
50 * of_irq_find_parent - Given a device node, find its interrupt parent node
51 * @child: pointer to device node
53 * Returns a pointer to the interrupt parent node, or NULL if the interrupt
54 * parent could not be determined.
56 struct device_node *of_irq_find_parent(struct device_node *child)
58 struct device_node *p;
59 const __be32 *parp;
61 if (!of_node_get(child))
62 return NULL;
64 do {
65 parp = of_get_property(child, "interrupt-parent", NULL);
66 if (parp == NULL)
67 p = of_get_parent(child);
68 else {
69 if (of_irq_workarounds & OF_IMAP_NO_PHANDLE)
70 p = of_node_get(of_irq_dflt_pic);
71 else
72 p = of_find_node_by_phandle(be32_to_cpup(parp));
74 of_node_put(child);
75 child = p;
76 } while (p && of_get_property(p, "#interrupt-cells", NULL) == NULL);
78 return p;
81 /**
82 * of_irq_map_raw - Low level interrupt tree parsing
83 * @parent: the device interrupt parent
84 * @intspec: interrupt specifier ("interrupts" property of the device)
85 * @ointsize: size of the passed in interrupt specifier
86 * @addr: address specifier (start of "reg" property of the device)
87 * @out_irq: structure of_irq filled by this function
89 * Returns 0 on success and a negative number on error
91 * This function is a low-level interrupt tree walking function. It
92 * can be used to do a partial walk with synthetized reg and interrupts
93 * properties, for example when resolving PCI interrupts when no device
94 * node exist for the parent.
96 int of_irq_map_raw(struct device_node *parent, const __be32 *intspec,
97 u32 ointsize, const __be32 *addr, struct of_irq *out_irq)
99 struct device_node *ipar, *tnode, *old = NULL, *newpar = NULL;
100 const __be32 *tmp, *imap, *imask;
101 u32 intsize = 1, addrsize, newintsize = 0, newaddrsize = 0;
102 int imaplen, match, i;
104 pr_debug("of_irq_map_raw: par=%s,intspec=[0x%08x 0x%08x...],ointsize=%d\n",
105 parent->full_name, be32_to_cpup(intspec),
106 be32_to_cpup(intspec + 1), ointsize);
108 ipar = of_node_get(parent);
110 /* First get the #interrupt-cells property of the current cursor
111 * that tells us how to interpret the passed-in intspec. If there
112 * is none, we are nice and just walk up the tree
114 do {
115 tmp = of_get_property(ipar, "#interrupt-cells", NULL);
116 if (tmp != NULL) {
117 intsize = be32_to_cpu(*tmp);
118 break;
120 tnode = ipar;
121 ipar = of_irq_find_parent(ipar);
122 of_node_put(tnode);
123 } while (ipar);
124 if (ipar == NULL) {
125 pr_debug(" -> no parent found !\n");
126 goto fail;
129 pr_debug("of_irq_map_raw: ipar=%s, size=%d\n", ipar->full_name, intsize);
131 if (ointsize != intsize)
132 return -EINVAL;
134 /* Look for this #address-cells. We have to implement the old linux
135 * trick of looking for the parent here as some device-trees rely on it
137 old = of_node_get(ipar);
138 do {
139 tmp = of_get_property(old, "#address-cells", NULL);
140 tnode = of_get_parent(old);
141 of_node_put(old);
142 old = tnode;
143 } while (old && tmp == NULL);
144 of_node_put(old);
145 old = NULL;
146 addrsize = (tmp == NULL) ? 2 : be32_to_cpu(*tmp);
148 pr_debug(" -> addrsize=%d\n", addrsize);
150 /* Now start the actual "proper" walk of the interrupt tree */
151 while (ipar != NULL) {
152 /* Now check if cursor is an interrupt-controller and if it is
153 * then we are done
155 if (of_get_property(ipar, "interrupt-controller", NULL) !=
156 NULL) {
157 pr_debug(" -> got it !\n");
158 for (i = 0; i < intsize; i++)
159 out_irq->specifier[i] =
160 of_read_number(intspec +i, 1);
161 out_irq->size = intsize;
162 out_irq->controller = ipar;
163 of_node_put(old);
164 return 0;
167 /* Now look for an interrupt-map */
168 imap = of_get_property(ipar, "interrupt-map", &imaplen);
169 /* No interrupt map, check for an interrupt parent */
170 if (imap == NULL) {
171 pr_debug(" -> no map, getting parent\n");
172 newpar = of_irq_find_parent(ipar);
173 goto skiplevel;
175 imaplen /= sizeof(u32);
177 /* Look for a mask */
178 imask = of_get_property(ipar, "interrupt-map-mask", NULL);
180 /* If we were passed no "reg" property and we attempt to parse
181 * an interrupt-map, then #address-cells must be 0.
182 * Fail if it's not.
184 if (addr == NULL && addrsize != 0) {
185 pr_debug(" -> no reg passed in when needed !\n");
186 goto fail;
189 /* Parse interrupt-map */
190 match = 0;
191 while (imaplen > (addrsize + intsize + 1) && !match) {
192 /* Compare specifiers */
193 match = 1;
194 for (i = 0; i < addrsize && match; ++i) {
195 __be32 mask = imask ? imask[i]
196 : cpu_to_be32(0xffffffffu);
197 match = ((addr[i] ^ imap[i]) & mask) == 0;
199 for (; i < (addrsize + intsize) && match; ++i) {
200 __be32 mask = imask ? imask[i]
201 : cpu_to_be32(0xffffffffu);
202 match =
203 ((intspec[i-addrsize] ^ imap[i]) & mask) == 0;
205 imap += addrsize + intsize;
206 imaplen -= addrsize + intsize;
208 pr_debug(" -> match=%d (imaplen=%d)\n", match, imaplen);
210 /* Get the interrupt parent */
211 if (of_irq_workarounds & OF_IMAP_NO_PHANDLE)
212 newpar = of_node_get(of_irq_dflt_pic);
213 else
214 newpar = of_find_node_by_phandle(be32_to_cpup(imap));
215 imap++;
216 --imaplen;
218 /* Check if not found */
219 if (newpar == NULL) {
220 pr_debug(" -> imap parent not found !\n");
221 goto fail;
224 /* Get #interrupt-cells and #address-cells of new
225 * parent
227 tmp = of_get_property(newpar, "#interrupt-cells", NULL);
228 if (tmp == NULL) {
229 pr_debug(" -> parent lacks #interrupt-cells!\n");
230 goto fail;
232 newintsize = be32_to_cpu(*tmp);
233 tmp = of_get_property(newpar, "#address-cells", NULL);
234 newaddrsize = (tmp == NULL) ? 0 : be32_to_cpu(*tmp);
236 pr_debug(" -> newintsize=%d, newaddrsize=%d\n",
237 newintsize, newaddrsize);
239 /* Check for malformed properties */
240 if (imaplen < (newaddrsize + newintsize))
241 goto fail;
243 imap += newaddrsize + newintsize;
244 imaplen -= newaddrsize + newintsize;
246 pr_debug(" -> imaplen=%d\n", imaplen);
248 if (!match)
249 goto fail;
251 of_node_put(old);
252 old = of_node_get(newpar);
253 addrsize = newaddrsize;
254 intsize = newintsize;
255 intspec = imap - intsize;
256 addr = intspec - addrsize;
258 skiplevel:
259 /* Iterate again with new parent */
260 pr_debug(" -> new parent: %s\n", of_node_full_name(newpar));
261 of_node_put(ipar);
262 ipar = newpar;
263 newpar = NULL;
265 fail:
266 of_node_put(ipar);
267 of_node_put(old);
268 of_node_put(newpar);
270 return -EINVAL;
272 EXPORT_SYMBOL_GPL(of_irq_map_raw);
275 * of_irq_map_one - Resolve an interrupt for a device
276 * @device: the device whose interrupt is to be resolved
277 * @index: index of the interrupt to resolve
278 * @out_irq: structure of_irq filled by this function
280 * This function resolves an interrupt, walking the tree, for a given
281 * device-tree node. It's the high level pendant to of_irq_map_raw().
283 int of_irq_map_one(struct device_node *device, int index, struct of_irq *out_irq)
285 struct device_node *p;
286 const __be32 *intspec, *tmp, *addr;
287 u32 intsize, intlen;
288 int res = -EINVAL;
290 pr_debug("of_irq_map_one: dev=%s, index=%d\n", device->full_name, index);
292 /* OldWorld mac stuff is "special", handle out of line */
293 if (of_irq_workarounds & OF_IMAP_OLDWORLD_MAC)
294 return of_irq_map_oldworld(device, index, out_irq);
296 /* Get the interrupts property */
297 intspec = of_get_property(device, "interrupts", &intlen);
298 if (intspec == NULL)
299 return -EINVAL;
300 intlen /= sizeof(*intspec);
302 pr_debug(" intspec=%d intlen=%d\n", be32_to_cpup(intspec), intlen);
304 /* Get the reg property (if any) */
305 addr = of_get_property(device, "reg", NULL);
307 /* Look for the interrupt parent. */
308 p = of_irq_find_parent(device);
309 if (p == NULL)
310 return -EINVAL;
312 /* Get size of interrupt specifier */
313 tmp = of_get_property(p, "#interrupt-cells", NULL);
314 if (tmp == NULL)
315 goto out;
316 intsize = be32_to_cpu(*tmp);
318 pr_debug(" intsize=%d intlen=%d\n", intsize, intlen);
320 /* Check index */
321 if ((index + 1) * intsize > intlen)
322 goto out;
324 /* Get new specifier and map it */
325 res = of_irq_map_raw(p, intspec + index * intsize, intsize,
326 addr, out_irq);
327 out:
328 of_node_put(p);
329 return res;
331 EXPORT_SYMBOL_GPL(of_irq_map_one);
334 * of_irq_to_resource - Decode a node's IRQ and return it as a resource
335 * @dev: pointer to device tree node
336 * @index: zero-based index of the irq
337 * @r: pointer to resource structure to return result into.
339 int of_irq_to_resource(struct device_node *dev, int index, struct resource *r)
341 int irq = irq_of_parse_and_map(dev, index);
343 /* Only dereference the resource if both the
344 * resource and the irq are valid. */
345 if (r && irq) {
346 const char *name = NULL;
348 memset(r, 0, sizeof(*r));
350 * Get optional "interrupts-names" property to add a name
351 * to the resource.
353 of_property_read_string_index(dev, "interrupt-names", index,
354 &name);
356 r->start = r->end = irq;
357 r->flags = IORESOURCE_IRQ;
358 r->name = name ? name : dev->full_name;
361 return irq;
363 EXPORT_SYMBOL_GPL(of_irq_to_resource);
366 * of_irq_count - Count the number of IRQs a node uses
367 * @dev: pointer to device tree node
369 int of_irq_count(struct device_node *dev)
371 int nr = 0;
373 while (of_irq_to_resource(dev, nr, NULL))
374 nr++;
376 return nr;
380 * of_irq_to_resource_table - Fill in resource table with node's IRQ info
381 * @dev: pointer to device tree node
382 * @res: array of resources to fill in
383 * @nr_irqs: the number of IRQs (and upper bound for num of @res elements)
385 * Returns the size of the filled in table (up to @nr_irqs).
387 int of_irq_to_resource_table(struct device_node *dev, struct resource *res,
388 int nr_irqs)
390 int i;
392 for (i = 0; i < nr_irqs; i++, res++)
393 if (!of_irq_to_resource(dev, i, res))
394 break;
396 return i;
398 EXPORT_SYMBOL_GPL(of_irq_to_resource_table);
400 struct intc_desc {
401 struct list_head list;
402 struct device_node *dev;
403 struct device_node *interrupt_parent;
407 * of_irq_init - Scan and init matching interrupt controllers in DT
408 * @matches: 0 terminated array of nodes to match and init function to call
410 * This function scans the device tree for matching interrupt controller nodes,
411 * and calls their initialization functions in order with parents first.
413 void __init of_irq_init(const struct of_device_id *matches)
415 struct device_node *np, *parent = NULL;
416 struct intc_desc *desc, *temp_desc;
417 struct list_head intc_desc_list, intc_parent_list;
419 INIT_LIST_HEAD(&intc_desc_list);
420 INIT_LIST_HEAD(&intc_parent_list);
422 for_each_matching_node(np, matches) {
423 if (!of_find_property(np, "interrupt-controller", NULL))
424 continue;
426 * Here, we allocate and populate an intc_desc with the node
427 * pointer, interrupt-parent device_node etc.
429 desc = kzalloc(sizeof(*desc), GFP_KERNEL);
430 if (WARN_ON(!desc))
431 goto err;
433 desc->dev = np;
434 desc->interrupt_parent = of_irq_find_parent(np);
435 if (desc->interrupt_parent == np)
436 desc->interrupt_parent = NULL;
437 list_add_tail(&desc->list, &intc_desc_list);
441 * The root irq controller is the one without an interrupt-parent.
442 * That one goes first, followed by the controllers that reference it,
443 * followed by the ones that reference the 2nd level controllers, etc.
445 while (!list_empty(&intc_desc_list)) {
447 * Process all controllers with the current 'parent'.
448 * First pass will be looking for NULL as the parent.
449 * The assumption is that NULL parent means a root controller.
451 list_for_each_entry_safe(desc, temp_desc, &intc_desc_list, list) {
452 const struct of_device_id *match;
453 int ret;
454 of_irq_init_cb_t irq_init_cb;
456 if (desc->interrupt_parent != parent)
457 continue;
459 list_del(&desc->list);
460 match = of_match_node(matches, desc->dev);
461 if (WARN(!match->data,
462 "of_irq_init: no init function for %s\n",
463 match->compatible)) {
464 kfree(desc);
465 continue;
468 pr_debug("of_irq_init: init %s @ %p, parent %p\n",
469 match->compatible,
470 desc->dev, desc->interrupt_parent);
471 irq_init_cb = (of_irq_init_cb_t)match->data;
472 ret = irq_init_cb(desc->dev, desc->interrupt_parent);
473 if (ret) {
474 kfree(desc);
475 continue;
479 * This one is now set up; add it to the parent list so
480 * its children can get processed in a subsequent pass.
482 list_add_tail(&desc->list, &intc_parent_list);
485 /* Get the next pending parent that might have children */
486 desc = list_first_entry_or_null(&intc_parent_list,
487 typeof(*desc), list);
488 if (!desc) {
489 pr_err("of_irq_init: children remain, but no parents\n");
490 break;
492 list_del(&desc->list);
493 parent = desc->dev;
494 kfree(desc);
497 list_for_each_entry_safe(desc, temp_desc, &intc_parent_list, list) {
498 list_del(&desc->list);
499 kfree(desc);
501 err:
502 list_for_each_entry_safe(desc, temp_desc, &intc_desc_list, list) {
503 list_del(&desc->list);
504 kfree(desc);