xref: /linux/drivers/pnp/manager.c (revision 2b8232ce512105e28453f301d1510de8363bccd1)
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@suse.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 "base.h"
16 
17 DECLARE_MUTEX(pnp_res_mutex);
18 
19 static int pnp_assign_port(struct pnp_dev *dev, struct pnp_port *rule, int idx)
20 {
21 	resource_size_t *start, *end;
22 	unsigned long *flags;
23 
24 	if (idx >= PNP_MAX_PORT) {
25 		pnp_err
26 		    ("More than 4 ports is incompatible with pnp specifications.");
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 		pnp_err
68 		    ("More than 8 mems is incompatible with pnp specifications.");
69 		/* pretend we were successful so at least the manager won't try again */
70 		return 1;
71 	}
72 
73 	/* check if this resource has been manually set, if so skip */
74 	if (!(dev->res.mem_resource[idx].flags & IORESOURCE_AUTO))
75 		return 1;
76 
77 	start = &dev->res.mem_resource[idx].start;
78 	end = &dev->res.mem_resource[idx].end;
79 	flags = &dev->res.mem_resource[idx].flags;
80 
81 	/* set the initial values */
82 	*flags |= rule->flags | IORESOURCE_MEM;
83 	*flags &= ~IORESOURCE_UNSET;
84 
85 	/* convert pnp flags to standard Linux flags */
86 	if (!(rule->flags & IORESOURCE_MEM_WRITEABLE))
87 		*flags |= IORESOURCE_READONLY;
88 	if (rule->flags & IORESOURCE_MEM_CACHEABLE)
89 		*flags |= IORESOURCE_CACHEABLE;
90 	if (rule->flags & IORESOURCE_MEM_RANGELENGTH)
91 		*flags |= IORESOURCE_RANGELENGTH;
92 	if (rule->flags & IORESOURCE_MEM_SHADOWABLE)
93 		*flags |= IORESOURCE_SHADOWABLE;
94 
95 	if (!rule->size) {
96 		*flags |= IORESOURCE_DISABLED;
97 		return 1;	/* skip disabled resource requests */
98 	}
99 
100 	*start = rule->min;
101 	*end = *start + rule->size - 1;
102 
103 	/* run through until pnp_check_mem is happy */
104 	while (!pnp_check_mem(dev, idx)) {
105 		*start += rule->align;
106 		*end = *start + rule->size - 1;
107 		if (*start > rule->max || !rule->align)
108 			return 0;
109 	}
110 	return 1;
111 }
112 
113 static int pnp_assign_irq(struct pnp_dev *dev, struct pnp_irq *rule, int idx)
114 {
115 	resource_size_t *start, *end;
116 	unsigned long *flags;
117 	int i;
118 
119 	/* IRQ priority: this table is good for i386 */
120 	static unsigned short xtab[16] = {
121 		5, 10, 11, 12, 9, 14, 15, 7, 3, 4, 13, 0, 1, 6, 8, 2
122 	};
123 
124 	if (idx >= PNP_MAX_IRQ) {
125 		pnp_err
126 		    ("More than 2 irqs is incompatible with pnp specifications.");
127 		/* pretend we were successful so at least the manager won't try again */
128 		return 1;
129 	}
130 
131 	/* check if this resource has been manually set, if so skip */
132 	if (!(dev->res.irq_resource[idx].flags & IORESOURCE_AUTO))
133 		return 1;
134 
135 	start = &dev->res.irq_resource[idx].start;
136 	end = &dev->res.irq_resource[idx].end;
137 	flags = &dev->res.irq_resource[idx].flags;
138 
139 	/* set the initial values */
140 	*flags |= rule->flags | IORESOURCE_IRQ;
141 	*flags &= ~IORESOURCE_UNSET;
142 
143 	if (bitmap_empty(rule->map, PNP_IRQ_NR)) {
144 		*flags |= IORESOURCE_DISABLED;
145 		return 1;	/* skip disabled resource requests */
146 	}
147 
148 	/* TBD: need check for >16 IRQ */
149 	*start = find_next_bit(rule->map, PNP_IRQ_NR, 16);
150 	if (*start < PNP_IRQ_NR) {
151 		*end = *start;
152 		return 1;
153 	}
154 	for (i = 0; i < 16; i++) {
155 		if (test_bit(xtab[i], rule->map)) {
156 			*start = *end = xtab[i];
157 			if (pnp_check_irq(dev, idx))
158 				return 1;
159 		}
160 	}
161 	return 0;
162 }
163 
164 static int pnp_assign_dma(struct pnp_dev *dev, struct pnp_dma *rule, int idx)
165 {
166 	resource_size_t *start, *end;
167 	unsigned long *flags;
168 	int i;
169 
170 	/* DMA priority: this table is good for i386 */
171 	static unsigned short xtab[8] = {
172 		1, 3, 5, 6, 7, 0, 2, 4
173 	};
174 
175 	if (idx >= PNP_MAX_DMA) {
176 		pnp_err
177 		    ("More than 2 dmas is incompatible with pnp specifications.");
178 		/* pretend we were successful so at least the manager won't try again */
179 		return 1;
180 	}
181 
182 	/* check if this resource has been manually set, if so skip */
183 	if (!(dev->res.dma_resource[idx].flags & IORESOURCE_AUTO))
184 		return 1;
185 
186 	start = &dev->res.dma_resource[idx].start;
187 	end = &dev->res.dma_resource[idx].end;
188 	flags = &dev->res.dma_resource[idx].flags;
189 
190 	/* set the initial values */
191 	*flags |= rule->flags | IORESOURCE_DMA;
192 	*flags &= ~IORESOURCE_UNSET;
193 
194 	if (!rule->map) {
195 		*flags |= IORESOURCE_DISABLED;
196 		return 1;	/* skip disabled resource requests */
197 	}
198 
199 	for (i = 0; i < 8; i++) {
200 		if (rule->map & (1 << xtab[i])) {
201 			*start = *end = xtab[i];
202 			if (pnp_check_dma(dev, idx))
203 				return 1;
204 		}
205 	}
206 	return 0;
207 }
208 
209 /**
210  * pnp_init_resources - Resets a resource table to default values.
211  * @table: pointer to the desired resource table
212  */
213 void pnp_init_resource_table(struct pnp_resource_table *table)
214 {
215 	int idx;
216 
217 	for (idx = 0; idx < PNP_MAX_IRQ; idx++) {
218 		table->irq_resource[idx].name = NULL;
219 		table->irq_resource[idx].start = -1;
220 		table->irq_resource[idx].end = -1;
221 		table->irq_resource[idx].flags =
222 		    IORESOURCE_IRQ | IORESOURCE_AUTO | IORESOURCE_UNSET;
223 	}
224 	for (idx = 0; idx < PNP_MAX_DMA; idx++) {
225 		table->dma_resource[idx].name = NULL;
226 		table->dma_resource[idx].start = -1;
227 		table->dma_resource[idx].end = -1;
228 		table->dma_resource[idx].flags =
229 		    IORESOURCE_DMA | IORESOURCE_AUTO | IORESOURCE_UNSET;
230 	}
231 	for (idx = 0; idx < PNP_MAX_PORT; idx++) {
232 		table->port_resource[idx].name = NULL;
233 		table->port_resource[idx].start = 0;
234 		table->port_resource[idx].end = 0;
235 		table->port_resource[idx].flags =
236 		    IORESOURCE_IO | IORESOURCE_AUTO | IORESOURCE_UNSET;
237 	}
238 	for (idx = 0; idx < PNP_MAX_MEM; idx++) {
239 		table->mem_resource[idx].name = NULL;
240 		table->mem_resource[idx].start = 0;
241 		table->mem_resource[idx].end = 0;
242 		table->mem_resource[idx].flags =
243 		    IORESOURCE_MEM | IORESOURCE_AUTO | IORESOURCE_UNSET;
244 	}
245 }
246 
247 /**
248  * pnp_clean_resources - clears resources that were not manually set
249  * @res: the resources to clean
250  */
251 static void pnp_clean_resource_table(struct pnp_resource_table *res)
252 {
253 	int idx;
254 
255 	for (idx = 0; idx < PNP_MAX_IRQ; idx++) {
256 		if (!(res->irq_resource[idx].flags & IORESOURCE_AUTO))
257 			continue;
258 		res->irq_resource[idx].start = -1;
259 		res->irq_resource[idx].end = -1;
260 		res->irq_resource[idx].flags =
261 		    IORESOURCE_IRQ | IORESOURCE_AUTO | IORESOURCE_UNSET;
262 	}
263 	for (idx = 0; idx < PNP_MAX_DMA; idx++) {
264 		if (!(res->dma_resource[idx].flags & IORESOURCE_AUTO))
265 			continue;
266 		res->dma_resource[idx].start = -1;
267 		res->dma_resource[idx].end = -1;
268 		res->dma_resource[idx].flags =
269 		    IORESOURCE_DMA | IORESOURCE_AUTO | IORESOURCE_UNSET;
270 	}
271 	for (idx = 0; idx < PNP_MAX_PORT; idx++) {
272 		if (!(res->port_resource[idx].flags & IORESOURCE_AUTO))
273 			continue;
274 		res->port_resource[idx].start = 0;
275 		res->port_resource[idx].end = 0;
276 		res->port_resource[idx].flags =
277 		    IORESOURCE_IO | IORESOURCE_AUTO | IORESOURCE_UNSET;
278 	}
279 	for (idx = 0; idx < PNP_MAX_MEM; idx++) {
280 		if (!(res->mem_resource[idx].flags & IORESOURCE_AUTO))
281 			continue;
282 		res->mem_resource[idx].start = 0;
283 		res->mem_resource[idx].end = 0;
284 		res->mem_resource[idx].flags =
285 		    IORESOURCE_MEM | IORESOURCE_AUTO | IORESOURCE_UNSET;
286 	}
287 }
288 
289 /**
290  * pnp_assign_resources - assigns resources to the device based on the specified dependent number
291  * @dev: pointer to the desired device
292  * @depnum: the dependent function number
293  *
294  * Only set depnum to 0 if the device does not have dependent options.
295  */
296 static int pnp_assign_resources(struct pnp_dev *dev, int depnum)
297 {
298 	struct pnp_port *port;
299 	struct pnp_mem *mem;
300 	struct pnp_irq *irq;
301 	struct pnp_dma *dma;
302 	int nport = 0, nmem = 0, nirq = 0, ndma = 0;
303 
304 	if (!pnp_can_configure(dev))
305 		return -ENODEV;
306 
307 	down(&pnp_res_mutex);
308 	pnp_clean_resource_table(&dev->res);	/* start with a fresh slate */
309 	if (dev->independent) {
310 		port = dev->independent->port;
311 		mem = dev->independent->mem;
312 		irq = dev->independent->irq;
313 		dma = dev->independent->dma;
314 		while (port) {
315 			if (!pnp_assign_port(dev, port, nport))
316 				goto fail;
317 			nport++;
318 			port = port->next;
319 		}
320 		while (mem) {
321 			if (!pnp_assign_mem(dev, mem, nmem))
322 				goto fail;
323 			nmem++;
324 			mem = mem->next;
325 		}
326 		while (irq) {
327 			if (!pnp_assign_irq(dev, irq, nirq))
328 				goto fail;
329 			nirq++;
330 			irq = irq->next;
331 		}
332 		while (dma) {
333 			if (!pnp_assign_dma(dev, dma, ndma))
334 				goto fail;
335 			ndma++;
336 			dma = dma->next;
337 		}
338 	}
339 
340 	if (depnum) {
341 		struct pnp_option *dep;
342 		int i;
343 		for (i = 1, dep = dev->dependent; i < depnum;
344 		     i++, dep = dep->next)
345 			if (!dep)
346 				goto fail;
347 		port = dep->port;
348 		mem = dep->mem;
349 		irq = dep->irq;
350 		dma = dep->dma;
351 		while (port) {
352 			if (!pnp_assign_port(dev, port, nport))
353 				goto fail;
354 			nport++;
355 			port = port->next;
356 		}
357 		while (mem) {
358 			if (!pnp_assign_mem(dev, mem, nmem))
359 				goto fail;
360 			nmem++;
361 			mem = mem->next;
362 		}
363 		while (irq) {
364 			if (!pnp_assign_irq(dev, irq, nirq))
365 				goto fail;
366 			nirq++;
367 			irq = irq->next;
368 		}
369 		while (dma) {
370 			if (!pnp_assign_dma(dev, dma, ndma))
371 				goto fail;
372 			ndma++;
373 			dma = dma->next;
374 		}
375 	} else if (dev->dependent)
376 		goto fail;
377 
378 	up(&pnp_res_mutex);
379 	return 1;
380 
381 fail:
382 	pnp_clean_resource_table(&dev->res);
383 	up(&pnp_res_mutex);
384 	return 0;
385 }
386 
387 /**
388  * pnp_manual_config_dev - Disables Auto Config and Manually sets the resource table
389  * @dev: pointer to the desired device
390  * @res: pointer to the new resource config
391  * @mode: 0 or PNP_CONFIG_FORCE
392  *
393  * This function can be used by drivers that want to manually set thier resources.
394  */
395 int pnp_manual_config_dev(struct pnp_dev *dev, struct pnp_resource_table *res,
396 			  int mode)
397 {
398 	int i;
399 	struct pnp_resource_table *bak;
400 
401 	if (!pnp_can_configure(dev))
402 		return -ENODEV;
403 	bak = pnp_alloc(sizeof(struct pnp_resource_table));
404 	if (!bak)
405 		return -ENOMEM;
406 	*bak = dev->res;
407 
408 	down(&pnp_res_mutex);
409 	dev->res = *res;
410 	if (!(mode & PNP_CONFIG_FORCE)) {
411 		for (i = 0; i < PNP_MAX_PORT; i++) {
412 			if (!pnp_check_port(dev, i))
413 				goto fail;
414 		}
415 		for (i = 0; i < PNP_MAX_MEM; i++) {
416 			if (!pnp_check_mem(dev, i))
417 				goto fail;
418 		}
419 		for (i = 0; i < PNP_MAX_IRQ; i++) {
420 			if (!pnp_check_irq(dev, i))
421 				goto fail;
422 		}
423 		for (i = 0; i < PNP_MAX_DMA; i++) {
424 			if (!pnp_check_dma(dev, i))
425 				goto fail;
426 		}
427 	}
428 	up(&pnp_res_mutex);
429 
430 	kfree(bak);
431 	return 0;
432 
433 fail:
434 	dev->res = *bak;
435 	up(&pnp_res_mutex);
436 	kfree(bak);
437 	return -EINVAL;
438 }
439 
440 /**
441  * pnp_auto_config_dev - automatically assigns resources to a device
442  * @dev: pointer to the desired device
443  */
444 int pnp_auto_config_dev(struct pnp_dev *dev)
445 {
446 	struct pnp_option *dep;
447 	int i = 1;
448 
449 	if (!pnp_can_configure(dev)) {
450 		pnp_dbg("Device %s does not support resource configuration.",
451 			dev->dev.bus_id);
452 		return -ENODEV;
453 	}
454 
455 	if (!dev->dependent) {
456 		if (pnp_assign_resources(dev, 0))
457 			return 0;
458 	} else {
459 		dep = dev->dependent;
460 		do {
461 			if (pnp_assign_resources(dev, i))
462 				return 0;
463 			dep = dep->next;
464 			i++;
465 		} while (dep);
466 	}
467 
468 	pnp_err("Unable to assign resources to device %s.", dev->dev.bus_id);
469 	return -EBUSY;
470 }
471 
472 /**
473  * pnp_start_dev - low-level start of the PnP device
474  * @dev: pointer to the desired device
475  *
476  * assumes that resources have already been allocated
477  */
478 int pnp_start_dev(struct pnp_dev *dev)
479 {
480 	if (!pnp_can_write(dev)) {
481 		pnp_dbg("Device %s does not support activation.",
482 			dev->dev.bus_id);
483 		return -EINVAL;
484 	}
485 
486 	if (dev->protocol->set(dev, &dev->res) < 0) {
487 		pnp_err("Failed to activate device %s.", dev->dev.bus_id);
488 		return -EIO;
489 	}
490 
491 	pnp_info("Device %s activated.", dev->dev.bus_id);
492 	return 0;
493 }
494 
495 /**
496  * pnp_stop_dev - low-level disable of the PnP device
497  * @dev: pointer to the desired device
498  *
499  * does not free resources
500  */
501 int pnp_stop_dev(struct pnp_dev *dev)
502 {
503 	if (!pnp_can_disable(dev)) {
504 		pnp_dbg("Device %s does not support disabling.",
505 			dev->dev.bus_id);
506 		return -EINVAL;
507 	}
508 	if (dev->protocol->disable(dev) < 0) {
509 		pnp_err("Failed to disable device %s.", dev->dev.bus_id);
510 		return -EIO;
511 	}
512 
513 	pnp_info("Device %s disabled.", dev->dev.bus_id);
514 	return 0;
515 }
516 
517 /**
518  * pnp_activate_dev - activates a PnP device for use
519  * @dev: pointer to the desired device
520  *
521  * does not validate or set resources so be careful.
522  */
523 int pnp_activate_dev(struct pnp_dev *dev)
524 {
525 	int error;
526 
527 	if (dev->active)
528 		return 0;	/* the device is already active */
529 
530 	/* ensure resources are allocated */
531 	if (pnp_auto_config_dev(dev))
532 		return -EBUSY;
533 
534 	error = pnp_start_dev(dev);
535 	if (error)
536 		return error;
537 
538 	dev->active = 1;
539 	return 1;
540 }
541 
542 /**
543  * pnp_disable_dev - disables device
544  * @dev: pointer to the desired device
545  *
546  * inform the correct pnp protocol so that resources can be used by other devices
547  */
548 int pnp_disable_dev(struct pnp_dev *dev)
549 {
550 	int error;
551 
552 	if (!dev->active)
553 		return 0;	/* the device is already disabled */
554 
555 	error = pnp_stop_dev(dev);
556 	if (error)
557 		return error;
558 
559 	dev->active = 0;
560 
561 	/* release the resources so that other devices can use them */
562 	down(&pnp_res_mutex);
563 	pnp_clean_resource_table(&dev->res);
564 	up(&pnp_res_mutex);
565 
566 	return 1;
567 }
568 
569 /**
570  * pnp_resource_change - change one resource
571  * @resource: pointer to resource to be changed
572  * @start: start of region
573  * @size: size of region
574  */
575 void pnp_resource_change(struct resource *resource, resource_size_t start,
576 			 resource_size_t size)
577 {
578 	resource->flags &= ~(IORESOURCE_AUTO | IORESOURCE_UNSET);
579 	resource->start = start;
580 	resource->end = start + size - 1;
581 }
582 
583 EXPORT_SYMBOL(pnp_manual_config_dev);
584 EXPORT_SYMBOL(pnp_start_dev);
585 EXPORT_SYMBOL(pnp_stop_dev);
586 EXPORT_SYMBOL(pnp_activate_dev);
587 EXPORT_SYMBOL(pnp_disable_dev);
588 EXPORT_SYMBOL(pnp_resource_change);
589 EXPORT_SYMBOL(pnp_init_resource_table);
590