xref: /openbmc/linux/drivers/pnp/manager.c (revision c21b37f6)
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 (!dev || !rule)
25 		return -EINVAL;
26 
27 	if (idx >= PNP_MAX_PORT) {
28 		pnp_err
29 		    ("More than 4 ports is incompatible with pnp specifications.");
30 		/* pretend we were successful so at least the manager won't try again */
31 		return 1;
32 	}
33 
34 	/* check if this resource has been manually set, if so skip */
35 	if (!(dev->res.port_resource[idx].flags & IORESOURCE_AUTO))
36 		return 1;
37 
38 	start = &dev->res.port_resource[idx].start;
39 	end = &dev->res.port_resource[idx].end;
40 	flags = &dev->res.port_resource[idx].flags;
41 
42 	/* set the initial values */
43 	*flags |= rule->flags | IORESOURCE_IO;
44 	*flags &= ~IORESOURCE_UNSET;
45 
46 	if (!rule->size) {
47 		*flags |= IORESOURCE_DISABLED;
48 		return 1;	/* skip disabled resource requests */
49 	}
50 
51 	*start = rule->min;
52 	*end = *start + rule->size - 1;
53 
54 	/* run through until pnp_check_port is happy */
55 	while (!pnp_check_port(dev, idx)) {
56 		*start += rule->align;
57 		*end = *start + rule->size - 1;
58 		if (*start > rule->max || !rule->align)
59 			return 0;
60 	}
61 	return 1;
62 }
63 
64 static int pnp_assign_mem(struct pnp_dev *dev, struct pnp_mem *rule, int idx)
65 {
66 	resource_size_t *start, *end;
67 	unsigned long *flags;
68 
69 	if (!dev || !rule)
70 		return -EINVAL;
71 
72 	if (idx >= PNP_MAX_MEM) {
73 		pnp_err
74 		    ("More than 8 mems is incompatible with pnp specifications.");
75 		/* pretend we were successful so at least the manager won't try again */
76 		return 1;
77 	}
78 
79 	/* check if this resource has been manually set, if so skip */
80 	if (!(dev->res.mem_resource[idx].flags & IORESOURCE_AUTO))
81 		return 1;
82 
83 	start = &dev->res.mem_resource[idx].start;
84 	end = &dev->res.mem_resource[idx].end;
85 	flags = &dev->res.mem_resource[idx].flags;
86 
87 	/* set the initial values */
88 	*flags |= rule->flags | IORESOURCE_MEM;
89 	*flags &= ~IORESOURCE_UNSET;
90 
91 	/* convert pnp flags to standard Linux flags */
92 	if (!(rule->flags & IORESOURCE_MEM_WRITEABLE))
93 		*flags |= IORESOURCE_READONLY;
94 	if (rule->flags & IORESOURCE_MEM_CACHEABLE)
95 		*flags |= IORESOURCE_CACHEABLE;
96 	if (rule->flags & IORESOURCE_MEM_RANGELENGTH)
97 		*flags |= IORESOURCE_RANGELENGTH;
98 	if (rule->flags & IORESOURCE_MEM_SHADOWABLE)
99 		*flags |= IORESOURCE_SHADOWABLE;
100 
101 	if (!rule->size) {
102 		*flags |= IORESOURCE_DISABLED;
103 		return 1;	/* skip disabled resource requests */
104 	}
105 
106 	*start = rule->min;
107 	*end = *start + rule->size - 1;
108 
109 	/* run through until pnp_check_mem is happy */
110 	while (!pnp_check_mem(dev, idx)) {
111 		*start += rule->align;
112 		*end = *start + rule->size - 1;
113 		if (*start > rule->max || !rule->align)
114 			return 0;
115 	}
116 	return 1;
117 }
118 
119 static int pnp_assign_irq(struct pnp_dev *dev, struct pnp_irq *rule, int idx)
120 {
121 	resource_size_t *start, *end;
122 	unsigned long *flags;
123 	int i;
124 
125 	/* IRQ priority: this table is good for i386 */
126 	static unsigned short xtab[16] = {
127 		5, 10, 11, 12, 9, 14, 15, 7, 3, 4, 13, 0, 1, 6, 8, 2
128 	};
129 
130 	if (!dev || !rule)
131 		return -EINVAL;
132 
133 	if (idx >= PNP_MAX_IRQ) {
134 		pnp_err
135 		    ("More than 2 irqs is incompatible with pnp specifications.");
136 		/* pretend we were successful so at least the manager won't try again */
137 		return 1;
138 	}
139 
140 	/* check if this resource has been manually set, if so skip */
141 	if (!(dev->res.irq_resource[idx].flags & IORESOURCE_AUTO))
142 		return 1;
143 
144 	start = &dev->res.irq_resource[idx].start;
145 	end = &dev->res.irq_resource[idx].end;
146 	flags = &dev->res.irq_resource[idx].flags;
147 
148 	/* set the initial values */
149 	*flags |= rule->flags | IORESOURCE_IRQ;
150 	*flags &= ~IORESOURCE_UNSET;
151 
152 	if (bitmap_empty(rule->map, PNP_IRQ_NR)) {
153 		*flags |= IORESOURCE_DISABLED;
154 		return 1;	/* skip disabled resource requests */
155 	}
156 
157 	/* TBD: need check for >16 IRQ */
158 	*start = find_next_bit(rule->map, PNP_IRQ_NR, 16);
159 	if (*start < PNP_IRQ_NR) {
160 		*end = *start;
161 		return 1;
162 	}
163 	for (i = 0; i < 16; i++) {
164 		if (test_bit(xtab[i], rule->map)) {
165 			*start = *end = xtab[i];
166 			if (pnp_check_irq(dev, idx))
167 				return 1;
168 		}
169 	}
170 	return 0;
171 }
172 
173 static int pnp_assign_dma(struct pnp_dev *dev, struct pnp_dma *rule, int idx)
174 {
175 	resource_size_t *start, *end;
176 	unsigned long *flags;
177 	int i;
178 
179 	/* DMA priority: this table is good for i386 */
180 	static unsigned short xtab[8] = {
181 		1, 3, 5, 6, 7, 0, 2, 4
182 	};
183 
184 	if (!dev || !rule)
185 		return -EINVAL;
186 
187 	if (idx >= PNP_MAX_DMA) {
188 		pnp_err
189 		    ("More than 2 dmas is incompatible with pnp specifications.");
190 		/* pretend we were successful so at least the manager won't try again */
191 		return 1;
192 	}
193 
194 	/* check if this resource has been manually set, if so skip */
195 	if (!(dev->res.dma_resource[idx].flags & IORESOURCE_AUTO))
196 		return 1;
197 
198 	start = &dev->res.dma_resource[idx].start;
199 	end = &dev->res.dma_resource[idx].end;
200 	flags = &dev->res.dma_resource[idx].flags;
201 
202 	/* set the initial values */
203 	*flags |= rule->flags | IORESOURCE_DMA;
204 	*flags &= ~IORESOURCE_UNSET;
205 
206 	if (!rule->map) {
207 		*flags |= IORESOURCE_DISABLED;
208 		return 1;	/* skip disabled resource requests */
209 	}
210 
211 	for (i = 0; i < 8; i++) {
212 		if (rule->map & (1 << xtab[i])) {
213 			*start = *end = xtab[i];
214 			if (pnp_check_dma(dev, idx))
215 				return 1;
216 		}
217 	}
218 	return 0;
219 }
220 
221 /**
222  * pnp_init_resources - Resets a resource table to default values.
223  * @table: pointer to the desired resource table
224  */
225 void pnp_init_resource_table(struct pnp_resource_table *table)
226 {
227 	int idx;
228 
229 	for (idx = 0; idx < PNP_MAX_IRQ; idx++) {
230 		table->irq_resource[idx].name = NULL;
231 		table->irq_resource[idx].start = -1;
232 		table->irq_resource[idx].end = -1;
233 		table->irq_resource[idx].flags =
234 		    IORESOURCE_IRQ | IORESOURCE_AUTO | IORESOURCE_UNSET;
235 	}
236 	for (idx = 0; idx < PNP_MAX_DMA; idx++) {
237 		table->dma_resource[idx].name = NULL;
238 		table->dma_resource[idx].start = -1;
239 		table->dma_resource[idx].end = -1;
240 		table->dma_resource[idx].flags =
241 		    IORESOURCE_DMA | IORESOURCE_AUTO | IORESOURCE_UNSET;
242 	}
243 	for (idx = 0; idx < PNP_MAX_PORT; idx++) {
244 		table->port_resource[idx].name = NULL;
245 		table->port_resource[idx].start = 0;
246 		table->port_resource[idx].end = 0;
247 		table->port_resource[idx].flags =
248 		    IORESOURCE_IO | IORESOURCE_AUTO | IORESOURCE_UNSET;
249 	}
250 	for (idx = 0; idx < PNP_MAX_MEM; idx++) {
251 		table->mem_resource[idx].name = NULL;
252 		table->mem_resource[idx].start = 0;
253 		table->mem_resource[idx].end = 0;
254 		table->mem_resource[idx].flags =
255 		    IORESOURCE_MEM | IORESOURCE_AUTO | IORESOURCE_UNSET;
256 	}
257 }
258 
259 /**
260  * pnp_clean_resources - clears resources that were not manually set
261  * @res: the resources to clean
262  */
263 static void pnp_clean_resource_table(struct pnp_resource_table *res)
264 {
265 	int idx;
266 
267 	for (idx = 0; idx < PNP_MAX_IRQ; idx++) {
268 		if (!(res->irq_resource[idx].flags & IORESOURCE_AUTO))
269 			continue;
270 		res->irq_resource[idx].start = -1;
271 		res->irq_resource[idx].end = -1;
272 		res->irq_resource[idx].flags =
273 		    IORESOURCE_IRQ | IORESOURCE_AUTO | IORESOURCE_UNSET;
274 	}
275 	for (idx = 0; idx < PNP_MAX_DMA; idx++) {
276 		if (!(res->dma_resource[idx].flags & IORESOURCE_AUTO))
277 			continue;
278 		res->dma_resource[idx].start = -1;
279 		res->dma_resource[idx].end = -1;
280 		res->dma_resource[idx].flags =
281 		    IORESOURCE_DMA | IORESOURCE_AUTO | IORESOURCE_UNSET;
282 	}
283 	for (idx = 0; idx < PNP_MAX_PORT; idx++) {
284 		if (!(res->port_resource[idx].flags & IORESOURCE_AUTO))
285 			continue;
286 		res->port_resource[idx].start = 0;
287 		res->port_resource[idx].end = 0;
288 		res->port_resource[idx].flags =
289 		    IORESOURCE_IO | IORESOURCE_AUTO | IORESOURCE_UNSET;
290 	}
291 	for (idx = 0; idx < PNP_MAX_MEM; idx++) {
292 		if (!(res->mem_resource[idx].flags & IORESOURCE_AUTO))
293 			continue;
294 		res->mem_resource[idx].start = 0;
295 		res->mem_resource[idx].end = 0;
296 		res->mem_resource[idx].flags =
297 		    IORESOURCE_MEM | IORESOURCE_AUTO | IORESOURCE_UNSET;
298 	}
299 }
300 
301 /**
302  * pnp_assign_resources - assigns resources to the device based on the specified dependent number
303  * @dev: pointer to the desired device
304  * @depnum: the dependent function number
305  *
306  * Only set depnum to 0 if the device does not have dependent options.
307  */
308 static int pnp_assign_resources(struct pnp_dev *dev, int depnum)
309 {
310 	struct pnp_port *port;
311 	struct pnp_mem *mem;
312 	struct pnp_irq *irq;
313 	struct pnp_dma *dma;
314 	int nport = 0, nmem = 0, nirq = 0, ndma = 0;
315 
316 	if (!pnp_can_configure(dev))
317 		return -ENODEV;
318 
319 	down(&pnp_res_mutex);
320 	pnp_clean_resource_table(&dev->res);	/* start with a fresh slate */
321 	if (dev->independent) {
322 		port = dev->independent->port;
323 		mem = dev->independent->mem;
324 		irq = dev->independent->irq;
325 		dma = dev->independent->dma;
326 		while (port) {
327 			if (!pnp_assign_port(dev, port, nport))
328 				goto fail;
329 			nport++;
330 			port = port->next;
331 		}
332 		while (mem) {
333 			if (!pnp_assign_mem(dev, mem, nmem))
334 				goto fail;
335 			nmem++;
336 			mem = mem->next;
337 		}
338 		while (irq) {
339 			if (!pnp_assign_irq(dev, irq, nirq))
340 				goto fail;
341 			nirq++;
342 			irq = irq->next;
343 		}
344 		while (dma) {
345 			if (!pnp_assign_dma(dev, dma, ndma))
346 				goto fail;
347 			ndma++;
348 			dma = dma->next;
349 		}
350 	}
351 
352 	if (depnum) {
353 		struct pnp_option *dep;
354 		int i;
355 		for (i = 1, dep = dev->dependent; i < depnum;
356 		     i++, dep = dep->next)
357 			if (!dep)
358 				goto fail;
359 		port = dep->port;
360 		mem = dep->mem;
361 		irq = dep->irq;
362 		dma = dep->dma;
363 		while (port) {
364 			if (!pnp_assign_port(dev, port, nport))
365 				goto fail;
366 			nport++;
367 			port = port->next;
368 		}
369 		while (mem) {
370 			if (!pnp_assign_mem(dev, mem, nmem))
371 				goto fail;
372 			nmem++;
373 			mem = mem->next;
374 		}
375 		while (irq) {
376 			if (!pnp_assign_irq(dev, irq, nirq))
377 				goto fail;
378 			nirq++;
379 			irq = irq->next;
380 		}
381 		while (dma) {
382 			if (!pnp_assign_dma(dev, dma, ndma))
383 				goto fail;
384 			ndma++;
385 			dma = dma->next;
386 		}
387 	} else if (dev->dependent)
388 		goto fail;
389 
390 	up(&pnp_res_mutex);
391 	return 1;
392 
393       fail:
394 	pnp_clean_resource_table(&dev->res);
395 	up(&pnp_res_mutex);
396 	return 0;
397 }
398 
399 /**
400  * pnp_manual_config_dev - Disables Auto Config and Manually sets the resource table
401  * @dev: pointer to the desired device
402  * @res: pointer to the new resource config
403  * @mode: 0 or PNP_CONFIG_FORCE
404  *
405  * This function can be used by drivers that want to manually set thier resources.
406  */
407 int pnp_manual_config_dev(struct pnp_dev *dev, struct pnp_resource_table *res,
408 			  int mode)
409 {
410 	int i;
411 	struct pnp_resource_table *bak;
412 
413 	if (!dev || !res)
414 		return -EINVAL;
415 	if (!pnp_can_configure(dev))
416 		return -ENODEV;
417 	bak = pnp_alloc(sizeof(struct pnp_resource_table));
418 	if (!bak)
419 		return -ENOMEM;
420 	*bak = dev->res;
421 
422 	down(&pnp_res_mutex);
423 	dev->res = *res;
424 	if (!(mode & PNP_CONFIG_FORCE)) {
425 		for (i = 0; i < PNP_MAX_PORT; i++) {
426 			if (!pnp_check_port(dev, i))
427 				goto fail;
428 		}
429 		for (i = 0; i < PNP_MAX_MEM; i++) {
430 			if (!pnp_check_mem(dev, i))
431 				goto fail;
432 		}
433 		for (i = 0; i < PNP_MAX_IRQ; i++) {
434 			if (!pnp_check_irq(dev, i))
435 				goto fail;
436 		}
437 		for (i = 0; i < PNP_MAX_DMA; i++) {
438 			if (!pnp_check_dma(dev, i))
439 				goto fail;
440 		}
441 	}
442 	up(&pnp_res_mutex);
443 
444 	kfree(bak);
445 	return 0;
446 
447       fail:
448 	dev->res = *bak;
449 	up(&pnp_res_mutex);
450 	kfree(bak);
451 	return -EINVAL;
452 }
453 
454 /**
455  * pnp_auto_config_dev - automatically assigns resources to a device
456  * @dev: pointer to the desired device
457  */
458 int pnp_auto_config_dev(struct pnp_dev *dev)
459 {
460 	struct pnp_option *dep;
461 	int i = 1;
462 
463 	if (!dev)
464 		return -EINVAL;
465 
466 	if (!pnp_can_configure(dev)) {
467 		pnp_dbg("Device %s does not support resource configuration.",
468 			dev->dev.bus_id);
469 		return -ENODEV;
470 	}
471 
472 	if (!dev->dependent) {
473 		if (pnp_assign_resources(dev, 0))
474 			return 0;
475 	} else {
476 		dep = dev->dependent;
477 		do {
478 			if (pnp_assign_resources(dev, i))
479 				return 0;
480 			dep = dep->next;
481 			i++;
482 		} while (dep);
483 	}
484 
485 	pnp_err("Unable to assign resources to device %s.", dev->dev.bus_id);
486 	return -EBUSY;
487 }
488 
489 /**
490  * pnp_start_dev - low-level start of the PnP device
491  * @dev: pointer to the desired device
492  *
493  * assumes that resources have already been allocated
494  */
495 int pnp_start_dev(struct pnp_dev *dev)
496 {
497 	if (!pnp_can_write(dev)) {
498 		pnp_dbg("Device %s does not support activation.",
499 			dev->dev.bus_id);
500 		return -EINVAL;
501 	}
502 
503 	if (dev->protocol->set(dev, &dev->res) < 0) {
504 		pnp_err("Failed to activate device %s.", dev->dev.bus_id);
505 		return -EIO;
506 	}
507 
508 	pnp_info("Device %s activated.", dev->dev.bus_id);
509 	return 0;
510 }
511 
512 /**
513  * pnp_stop_dev - low-level disable of the PnP device
514  * @dev: pointer to the desired device
515  *
516  * does not free resources
517  */
518 int pnp_stop_dev(struct pnp_dev *dev)
519 {
520 	if (!pnp_can_disable(dev)) {
521 		pnp_dbg("Device %s does not support disabling.",
522 			dev->dev.bus_id);
523 		return -EINVAL;
524 	}
525 	if (dev->protocol->disable(dev) < 0) {
526 		pnp_err("Failed to disable device %s.", dev->dev.bus_id);
527 		return -EIO;
528 	}
529 
530 	pnp_info("Device %s disabled.", dev->dev.bus_id);
531 	return 0;
532 }
533 
534 /**
535  * pnp_activate_dev - activates a PnP device for use
536  * @dev: pointer to the desired device
537  *
538  * does not validate or set resources so be careful.
539  */
540 int pnp_activate_dev(struct pnp_dev *dev)
541 {
542 	int error;
543 
544 	if (!dev)
545 		return -EINVAL;
546 	if (dev->active)
547 		return 0;	/* the device is already active */
548 
549 	/* ensure resources are allocated */
550 	if (pnp_auto_config_dev(dev))
551 		return -EBUSY;
552 
553 	error = pnp_start_dev(dev);
554 	if (error)
555 		return error;
556 
557 	dev->active = 1;
558 	return 1;
559 }
560 
561 /**
562  * pnp_disable_dev - disables device
563  * @dev: pointer to the desired device
564  *
565  * inform the correct pnp protocol so that resources can be used by other devices
566  */
567 int pnp_disable_dev(struct pnp_dev *dev)
568 {
569 	int error;
570 
571 	if (!dev)
572 		return -EINVAL;
573 	if (!dev->active)
574 		return 0;	/* the device is already disabled */
575 
576 	error = pnp_stop_dev(dev);
577 	if (error)
578 		return error;
579 
580 	dev->active = 0;
581 
582 	/* release the resources so that other devices can use them */
583 	down(&pnp_res_mutex);
584 	pnp_clean_resource_table(&dev->res);
585 	up(&pnp_res_mutex);
586 
587 	return 1;
588 }
589 
590 /**
591  * pnp_resource_change - change one resource
592  * @resource: pointer to resource to be changed
593  * @start: start of region
594  * @size: size of region
595  */
596 void pnp_resource_change(struct resource *resource, resource_size_t start,
597 			 resource_size_t size)
598 {
599 	if (resource == NULL)
600 		return;
601 	resource->flags &= ~(IORESOURCE_AUTO | IORESOURCE_UNSET);
602 	resource->start = start;
603 	resource->end = start + size - 1;
604 }
605 
606 EXPORT_SYMBOL(pnp_manual_config_dev);
607 EXPORT_SYMBOL(pnp_start_dev);
608 EXPORT_SYMBOL(pnp_stop_dev);
609 EXPORT_SYMBOL(pnp_activate_dev);
610 EXPORT_SYMBOL(pnp_disable_dev);
611 EXPORT_SYMBOL(pnp_resource_change);
612 EXPORT_SYMBOL(pnp_init_resource_table);
613