xref: /linux/drivers/pnp/manager.c (revision f7511d5f66f01fc451747b24e79f3ada7a3af9af)
1 /*
2  * manager.c - Resource Management, Conflict Resolution, Activation and Disabling of Devices
3  *
4  * based on isapnp.c resource management (c) Jaroslav Kysela <perex@perex.cz>
5  * Copyright 2003 Adam Belay <ambx1@neo.rr.com>
6  */
7 
8 #include <linux/errno.h>
9 #include <linux/module.h>
10 #include <linux/init.h>
11 #include <linux/kernel.h>
12 #include <linux/pnp.h>
13 #include <linux/slab.h>
14 #include <linux/bitmap.h>
15 #include <linux/mutex.h>
16 #include "base.h"
17 
18 DEFINE_MUTEX(pnp_res_mutex);
19 
20 static int pnp_assign_port(struct pnp_dev *dev, struct pnp_port *rule, int idx)
21 {
22 	resource_size_t *start, *end;
23 	unsigned long *flags;
24 
25 	if (idx >= PNP_MAX_PORT) {
26 		dev_err(&dev->dev, "too many I/O port resources\n");
27 		/* pretend we were successful so at least the manager won't try again */
28 		return 1;
29 	}
30 
31 	/* check if this resource has been manually set, if so skip */
32 	if (!(dev->res.port_resource[idx].flags & IORESOURCE_AUTO))
33 		return 1;
34 
35 	start = &dev->res.port_resource[idx].start;
36 	end = &dev->res.port_resource[idx].end;
37 	flags = &dev->res.port_resource[idx].flags;
38 
39 	/* set the initial values */
40 	*flags |= rule->flags | IORESOURCE_IO;
41 	*flags &= ~IORESOURCE_UNSET;
42 
43 	if (!rule->size) {
44 		*flags |= IORESOURCE_DISABLED;
45 		return 1;	/* skip disabled resource requests */
46 	}
47 
48 	*start = rule->min;
49 	*end = *start + rule->size - 1;
50 
51 	/* run through until pnp_check_port is happy */
52 	while (!pnp_check_port(dev, idx)) {
53 		*start += rule->align;
54 		*end = *start + rule->size - 1;
55 		if (*start > rule->max || !rule->align)
56 			return 0;
57 	}
58 	return 1;
59 }
60 
61 static int pnp_assign_mem(struct pnp_dev *dev, struct pnp_mem *rule, int idx)
62 {
63 	resource_size_t *start, *end;
64 	unsigned long *flags;
65 
66 	if (idx >= PNP_MAX_MEM) {
67 		dev_err(&dev->dev, "too many memory resources\n");
68 		/* pretend we were successful so at least the manager won't try again */
69 		return 1;
70 	}
71 
72 	/* check if this resource has been manually set, if so skip */
73 	if (!(dev->res.mem_resource[idx].flags & IORESOURCE_AUTO))
74 		return 1;
75 
76 	start = &dev->res.mem_resource[idx].start;
77 	end = &dev->res.mem_resource[idx].end;
78 	flags = &dev->res.mem_resource[idx].flags;
79 
80 	/* set the initial values */
81 	*flags |= rule->flags | IORESOURCE_MEM;
82 	*flags &= ~IORESOURCE_UNSET;
83 
84 	/* convert pnp flags to standard Linux flags */
85 	if (!(rule->flags & IORESOURCE_MEM_WRITEABLE))
86 		*flags |= IORESOURCE_READONLY;
87 	if (rule->flags & IORESOURCE_MEM_CACHEABLE)
88 		*flags |= IORESOURCE_CACHEABLE;
89 	if (rule->flags & IORESOURCE_MEM_RANGELENGTH)
90 		*flags |= IORESOURCE_RANGELENGTH;
91 	if (rule->flags & IORESOURCE_MEM_SHADOWABLE)
92 		*flags |= IORESOURCE_SHADOWABLE;
93 
94 	if (!rule->size) {
95 		*flags |= IORESOURCE_DISABLED;
96 		return 1;	/* skip disabled resource requests */
97 	}
98 
99 	*start = rule->min;
100 	*end = *start + rule->size - 1;
101 
102 	/* run through until pnp_check_mem is happy */
103 	while (!pnp_check_mem(dev, idx)) {
104 		*start += rule->align;
105 		*end = *start + rule->size - 1;
106 		if (*start > rule->max || !rule->align)
107 			return 0;
108 	}
109 	return 1;
110 }
111 
112 static int pnp_assign_irq(struct pnp_dev *dev, struct pnp_irq *rule, int idx)
113 {
114 	resource_size_t *start, *end;
115 	unsigned long *flags;
116 	int i;
117 
118 	/* IRQ priority: this table is good for i386 */
119 	static unsigned short xtab[16] = {
120 		5, 10, 11, 12, 9, 14, 15, 7, 3, 4, 13, 0, 1, 6, 8, 2
121 	};
122 
123 	if (idx >= PNP_MAX_IRQ) {
124 		dev_err(&dev->dev, "too many IRQ resources\n");
125 		/* pretend we were successful so at least the manager won't try again */
126 		return 1;
127 	}
128 
129 	/* check if this resource has been manually set, if so skip */
130 	if (!(dev->res.irq_resource[idx].flags & IORESOURCE_AUTO))
131 		return 1;
132 
133 	start = &dev->res.irq_resource[idx].start;
134 	end = &dev->res.irq_resource[idx].end;
135 	flags = &dev->res.irq_resource[idx].flags;
136 
137 	/* set the initial values */
138 	*flags |= rule->flags | IORESOURCE_IRQ;
139 	*flags &= ~IORESOURCE_UNSET;
140 
141 	if (bitmap_empty(rule->map, PNP_IRQ_NR)) {
142 		*flags |= IORESOURCE_DISABLED;
143 		return 1;	/* skip disabled resource requests */
144 	}
145 
146 	/* TBD: need check for >16 IRQ */
147 	*start = find_next_bit(rule->map, PNP_IRQ_NR, 16);
148 	if (*start < PNP_IRQ_NR) {
149 		*end = *start;
150 		return 1;
151 	}
152 	for (i = 0; i < 16; i++) {
153 		if (test_bit(xtab[i], rule->map)) {
154 			*start = *end = xtab[i];
155 			if (pnp_check_irq(dev, idx))
156 				return 1;
157 		}
158 	}
159 	return 0;
160 }
161 
162 static void pnp_assign_dma(struct pnp_dev *dev, struct pnp_dma *rule, int idx)
163 {
164 	resource_size_t *start, *end;
165 	unsigned long *flags;
166 	int i;
167 
168 	/* DMA priority: this table is good for i386 */
169 	static unsigned short xtab[8] = {
170 		1, 3, 5, 6, 7, 0, 2, 4
171 	};
172 
173 	if (idx >= PNP_MAX_DMA) {
174 		dev_err(&dev->dev, "too many DMA resources\n");
175 		return;
176 	}
177 
178 	/* check if this resource has been manually set, if so skip */
179 	if (!(dev->res.dma_resource[idx].flags & IORESOURCE_AUTO))
180 		return;
181 
182 	start = &dev->res.dma_resource[idx].start;
183 	end = &dev->res.dma_resource[idx].end;
184 	flags = &dev->res.dma_resource[idx].flags;
185 
186 	/* set the initial values */
187 	*flags |= rule->flags | IORESOURCE_DMA;
188 	*flags &= ~IORESOURCE_UNSET;
189 
190 	for (i = 0; i < 8; i++) {
191 		if (rule->map & (1 << xtab[i])) {
192 			*start = *end = xtab[i];
193 			if (pnp_check_dma(dev, idx))
194 				return;
195 		}
196 	}
197 #ifdef MAX_DMA_CHANNELS
198 	*start = *end = MAX_DMA_CHANNELS;
199 #endif
200 	*flags |= IORESOURCE_UNSET | IORESOURCE_DISABLED;
201 }
202 
203 /**
204  * pnp_init_resources - Resets a resource table to default values.
205  * @table: pointer to the desired resource table
206  */
207 void pnp_init_resource_table(struct pnp_resource_table *table)
208 {
209 	int idx;
210 
211 	for (idx = 0; idx < PNP_MAX_IRQ; idx++) {
212 		table->irq_resource[idx].name = NULL;
213 		table->irq_resource[idx].start = -1;
214 		table->irq_resource[idx].end = -1;
215 		table->irq_resource[idx].flags =
216 		    IORESOURCE_IRQ | IORESOURCE_AUTO | IORESOURCE_UNSET;
217 	}
218 	for (idx = 0; idx < PNP_MAX_DMA; idx++) {
219 		table->dma_resource[idx].name = NULL;
220 		table->dma_resource[idx].start = -1;
221 		table->dma_resource[idx].end = -1;
222 		table->dma_resource[idx].flags =
223 		    IORESOURCE_DMA | IORESOURCE_AUTO | IORESOURCE_UNSET;
224 	}
225 	for (idx = 0; idx < PNP_MAX_PORT; idx++) {
226 		table->port_resource[idx].name = NULL;
227 		table->port_resource[idx].start = 0;
228 		table->port_resource[idx].end = 0;
229 		table->port_resource[idx].flags =
230 		    IORESOURCE_IO | IORESOURCE_AUTO | IORESOURCE_UNSET;
231 	}
232 	for (idx = 0; idx < PNP_MAX_MEM; idx++) {
233 		table->mem_resource[idx].name = NULL;
234 		table->mem_resource[idx].start = 0;
235 		table->mem_resource[idx].end = 0;
236 		table->mem_resource[idx].flags =
237 		    IORESOURCE_MEM | IORESOURCE_AUTO | IORESOURCE_UNSET;
238 	}
239 }
240 
241 /**
242  * pnp_clean_resources - clears resources that were not manually set
243  * @res: the resources to clean
244  */
245 static void pnp_clean_resource_table(struct pnp_resource_table *res)
246 {
247 	int idx;
248 
249 	for (idx = 0; idx < PNP_MAX_IRQ; idx++) {
250 		if (!(res->irq_resource[idx].flags & IORESOURCE_AUTO))
251 			continue;
252 		res->irq_resource[idx].start = -1;
253 		res->irq_resource[idx].end = -1;
254 		res->irq_resource[idx].flags =
255 		    IORESOURCE_IRQ | IORESOURCE_AUTO | IORESOURCE_UNSET;
256 	}
257 	for (idx = 0; idx < PNP_MAX_DMA; idx++) {
258 		if (!(res->dma_resource[idx].flags & IORESOURCE_AUTO))
259 			continue;
260 		res->dma_resource[idx].start = -1;
261 		res->dma_resource[idx].end = -1;
262 		res->dma_resource[idx].flags =
263 		    IORESOURCE_DMA | IORESOURCE_AUTO | IORESOURCE_UNSET;
264 	}
265 	for (idx = 0; idx < PNP_MAX_PORT; idx++) {
266 		if (!(res->port_resource[idx].flags & IORESOURCE_AUTO))
267 			continue;
268 		res->port_resource[idx].start = 0;
269 		res->port_resource[idx].end = 0;
270 		res->port_resource[idx].flags =
271 		    IORESOURCE_IO | IORESOURCE_AUTO | IORESOURCE_UNSET;
272 	}
273 	for (idx = 0; idx < PNP_MAX_MEM; idx++) {
274 		if (!(res->mem_resource[idx].flags & IORESOURCE_AUTO))
275 			continue;
276 		res->mem_resource[idx].start = 0;
277 		res->mem_resource[idx].end = 0;
278 		res->mem_resource[idx].flags =
279 		    IORESOURCE_MEM | IORESOURCE_AUTO | IORESOURCE_UNSET;
280 	}
281 }
282 
283 /**
284  * pnp_assign_resources - assigns resources to the device based on the specified dependent number
285  * @dev: pointer to the desired device
286  * @depnum: the dependent function number
287  *
288  * Only set depnum to 0 if the device does not have dependent options.
289  */
290 static int pnp_assign_resources(struct pnp_dev *dev, int depnum)
291 {
292 	struct pnp_port *port;
293 	struct pnp_mem *mem;
294 	struct pnp_irq *irq;
295 	struct pnp_dma *dma;
296 	int nport = 0, nmem = 0, nirq = 0, ndma = 0;
297 
298 	if (!pnp_can_configure(dev))
299 		return -ENODEV;
300 
301 	mutex_lock(&pnp_res_mutex);
302 	pnp_clean_resource_table(&dev->res);	/* start with a fresh slate */
303 	if (dev->independent) {
304 		port = dev->independent->port;
305 		mem = dev->independent->mem;
306 		irq = dev->independent->irq;
307 		dma = dev->independent->dma;
308 		while (port) {
309 			if (!pnp_assign_port(dev, port, nport))
310 				goto fail;
311 			nport++;
312 			port = port->next;
313 		}
314 		while (mem) {
315 			if (!pnp_assign_mem(dev, mem, nmem))
316 				goto fail;
317 			nmem++;
318 			mem = mem->next;
319 		}
320 		while (irq) {
321 			if (!pnp_assign_irq(dev, irq, nirq))
322 				goto fail;
323 			nirq++;
324 			irq = irq->next;
325 		}
326 		while (dma) {
327 			pnp_assign_dma(dev, dma, ndma);
328 			ndma++;
329 			dma = dma->next;
330 		}
331 	}
332 
333 	if (depnum) {
334 		struct pnp_option *dep;
335 		int i;
336 		for (i = 1, dep = dev->dependent; i < depnum;
337 		     i++, dep = dep->next)
338 			if (!dep)
339 				goto fail;
340 		port = dep->port;
341 		mem = dep->mem;
342 		irq = dep->irq;
343 		dma = dep->dma;
344 		while (port) {
345 			if (!pnp_assign_port(dev, port, nport))
346 				goto fail;
347 			nport++;
348 			port = port->next;
349 		}
350 		while (mem) {
351 			if (!pnp_assign_mem(dev, mem, nmem))
352 				goto fail;
353 			nmem++;
354 			mem = mem->next;
355 		}
356 		while (irq) {
357 			if (!pnp_assign_irq(dev, irq, nirq))
358 				goto fail;
359 			nirq++;
360 			irq = irq->next;
361 		}
362 		while (dma) {
363 			pnp_assign_dma(dev, dma, ndma);
364 			ndma++;
365 			dma = dma->next;
366 		}
367 	} else if (dev->dependent)
368 		goto fail;
369 
370 	mutex_unlock(&pnp_res_mutex);
371 	return 1;
372 
373 fail:
374 	pnp_clean_resource_table(&dev->res);
375 	mutex_unlock(&pnp_res_mutex);
376 	return 0;
377 }
378 
379 /**
380  * pnp_manual_config_dev - Disables Auto Config and Manually sets the resource table
381  * @dev: pointer to the desired device
382  * @res: pointer to the new resource config
383  * @mode: 0 or PNP_CONFIG_FORCE
384  *
385  * This function can be used by drivers that want to manually set thier resources.
386  */
387 int pnp_manual_config_dev(struct pnp_dev *dev, struct pnp_resource_table *res,
388 			  int mode)
389 {
390 	int i;
391 	struct pnp_resource_table *bak;
392 
393 	if (!pnp_can_configure(dev))
394 		return -ENODEV;
395 	bak = pnp_alloc(sizeof(struct pnp_resource_table));
396 	if (!bak)
397 		return -ENOMEM;
398 	*bak = dev->res;
399 
400 	mutex_lock(&pnp_res_mutex);
401 	dev->res = *res;
402 	if (!(mode & PNP_CONFIG_FORCE)) {
403 		for (i = 0; i < PNP_MAX_PORT; i++) {
404 			if (!pnp_check_port(dev, i))
405 				goto fail;
406 		}
407 		for (i = 0; i < PNP_MAX_MEM; i++) {
408 			if (!pnp_check_mem(dev, i))
409 				goto fail;
410 		}
411 		for (i = 0; i < PNP_MAX_IRQ; i++) {
412 			if (!pnp_check_irq(dev, i))
413 				goto fail;
414 		}
415 		for (i = 0; i < PNP_MAX_DMA; i++) {
416 			if (!pnp_check_dma(dev, i))
417 				goto fail;
418 		}
419 	}
420 	mutex_unlock(&pnp_res_mutex);
421 
422 	kfree(bak);
423 	return 0;
424 
425 fail:
426 	dev->res = *bak;
427 	mutex_unlock(&pnp_res_mutex);
428 	kfree(bak);
429 	return -EINVAL;
430 }
431 
432 /**
433  * pnp_auto_config_dev - automatically assigns resources to a device
434  * @dev: pointer to the desired device
435  */
436 int pnp_auto_config_dev(struct pnp_dev *dev)
437 {
438 	struct pnp_option *dep;
439 	int i = 1;
440 
441 	if (!pnp_can_configure(dev)) {
442 		dev_dbg(&dev->dev, "configuration not supported\n");
443 		return -ENODEV;
444 	}
445 
446 	if (!dev->dependent) {
447 		if (pnp_assign_resources(dev, 0))
448 			return 0;
449 	} else {
450 		dep = dev->dependent;
451 		do {
452 			if (pnp_assign_resources(dev, i))
453 				return 0;
454 			dep = dep->next;
455 			i++;
456 		} while (dep);
457 	}
458 
459 	dev_err(&dev->dev, "unable to assign resources\n");
460 	return -EBUSY;
461 }
462 
463 /**
464  * pnp_start_dev - low-level start of the PnP device
465  * @dev: pointer to the desired device
466  *
467  * assumes that resources have already been allocated
468  */
469 int pnp_start_dev(struct pnp_dev *dev)
470 {
471 	if (!pnp_can_write(dev)) {
472 		dev_dbg(&dev->dev, "activation not supported\n");
473 		return -EINVAL;
474 	}
475 
476 	if (dev->protocol->set(dev, &dev->res) < 0) {
477 		dev_err(&dev->dev, "activation failed\n");
478 		return -EIO;
479 	}
480 
481 	dev_info(&dev->dev, "activated\n");
482 	return 0;
483 }
484 
485 /**
486  * pnp_stop_dev - low-level disable of the PnP device
487  * @dev: pointer to the desired device
488  *
489  * does not free resources
490  */
491 int pnp_stop_dev(struct pnp_dev *dev)
492 {
493 	if (!pnp_can_disable(dev)) {
494 		dev_dbg(&dev->dev, "disabling not supported\n");
495 		return -EINVAL;
496 	}
497 	if (dev->protocol->disable(dev) < 0) {
498 		dev_err(&dev->dev, "disable failed\n");
499 		return -EIO;
500 	}
501 
502 	dev_info(&dev->dev, "disabled\n");
503 	return 0;
504 }
505 
506 /**
507  * pnp_activate_dev - activates a PnP device for use
508  * @dev: pointer to the desired device
509  *
510  * does not validate or set resources so be careful.
511  */
512 int pnp_activate_dev(struct pnp_dev *dev)
513 {
514 	int error;
515 
516 	if (dev->active)
517 		return 0;
518 
519 	/* ensure resources are allocated */
520 	if (pnp_auto_config_dev(dev))
521 		return -EBUSY;
522 
523 	error = pnp_start_dev(dev);
524 	if (error)
525 		return error;
526 
527 	dev->active = 1;
528 	return 0;
529 }
530 
531 /**
532  * pnp_disable_dev - disables device
533  * @dev: pointer to the desired device
534  *
535  * inform the correct pnp protocol so that resources can be used by other devices
536  */
537 int pnp_disable_dev(struct pnp_dev *dev)
538 {
539 	int error;
540 
541 	if (!dev->active)
542 		return 0;
543 
544 	error = pnp_stop_dev(dev);
545 	if (error)
546 		return error;
547 
548 	dev->active = 0;
549 
550 	/* release the resources so that other devices can use them */
551 	mutex_lock(&pnp_res_mutex);
552 	pnp_clean_resource_table(&dev->res);
553 	mutex_unlock(&pnp_res_mutex);
554 
555 	return 0;
556 }
557 
558 /**
559  * pnp_resource_change - change one resource
560  * @resource: pointer to resource to be changed
561  * @start: start of region
562  * @size: size of region
563  */
564 void pnp_resource_change(struct resource *resource, resource_size_t start,
565 			 resource_size_t size)
566 {
567 	resource->flags &= ~(IORESOURCE_AUTO | IORESOURCE_UNSET);
568 	resource->start = start;
569 	resource->end = start + size - 1;
570 }
571 
572 EXPORT_SYMBOL(pnp_manual_config_dev);
573 EXPORT_SYMBOL(pnp_start_dev);
574 EXPORT_SYMBOL(pnp_stop_dev);
575 EXPORT_SYMBOL(pnp_activate_dev);
576 EXPORT_SYMBOL(pnp_disable_dev);
577 EXPORT_SYMBOL(pnp_resource_change);
578 EXPORT_SYMBOL(pnp_init_resource_table);
579