xref: /linux/drivers/pnp/manager.c (revision f3a8b6645dc2e60d11f20c1c23afd964ff4e55ae)
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  * Copyright (C) 2008 Hewlett-Packard Development Company, L.P.
7  *	Bjorn Helgaas <bjorn.helgaas@hp.com>
8  */
9 
10 #include <linux/errno.h>
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/kernel.h>
14 #include <linux/pnp.h>
15 #include <linux/bitmap.h>
16 #include <linux/mutex.h>
17 #include "base.h"
18 
19 DEFINE_MUTEX(pnp_res_mutex);
20 
21 static struct resource *pnp_find_resource(struct pnp_dev *dev,
22 					  unsigned char rule,
23 					  unsigned long type,
24 					  unsigned int bar)
25 {
26 	struct resource *res = pnp_get_resource(dev, type, bar);
27 
28 	/* when the resource already exists, set its resource bits from rule */
29 	if (res) {
30 		res->flags &= ~IORESOURCE_BITS;
31 		res->flags |= rule & IORESOURCE_BITS;
32 	}
33 
34 	return res;
35 }
36 
37 static int pnp_assign_port(struct pnp_dev *dev, struct pnp_port *rule, int idx)
38 {
39 	struct resource *res, local_res;
40 
41 	res = pnp_find_resource(dev, rule->flags, IORESOURCE_IO, idx);
42 	if (res) {
43 		pnp_dbg(&dev->dev, "  io %d already set to %#llx-%#llx "
44 			"flags %#lx\n", idx, (unsigned long long) res->start,
45 			(unsigned long long) res->end, res->flags);
46 		return 0;
47 	}
48 
49 	res = &local_res;
50 	res->flags = rule->flags | IORESOURCE_AUTO;
51 	res->start = 0;
52 	res->end = 0;
53 
54 	if (!rule->size) {
55 		res->flags |= IORESOURCE_DISABLED;
56 		pnp_dbg(&dev->dev, "  io %d disabled\n", idx);
57 		goto __add;
58 	}
59 
60 	res->start = rule->min;
61 	res->end = res->start + rule->size - 1;
62 
63 	while (!pnp_check_port(dev, res)) {
64 		res->start += rule->align;
65 		res->end = res->start + rule->size - 1;
66 		if (res->start > rule->max || !rule->align) {
67 			pnp_dbg(&dev->dev, "  couldn't assign io %d "
68 				"(min %#llx max %#llx)\n", idx,
69 				(unsigned long long) rule->min,
70 				(unsigned long long) rule->max);
71 			return -EBUSY;
72 		}
73 	}
74 
75 __add:
76 	pnp_add_io_resource(dev, res->start, res->end, res->flags);
77 	return 0;
78 }
79 
80 static int pnp_assign_mem(struct pnp_dev *dev, struct pnp_mem *rule, int idx)
81 {
82 	struct resource *res, local_res;
83 
84 	res = pnp_find_resource(dev, rule->flags, IORESOURCE_MEM, idx);
85 	if (res) {
86 		pnp_dbg(&dev->dev, "  mem %d already set to %#llx-%#llx "
87 			"flags %#lx\n", idx, (unsigned long long) res->start,
88 			(unsigned long long) res->end, res->flags);
89 		return 0;
90 	}
91 
92 	res = &local_res;
93 	res->flags = rule->flags | IORESOURCE_AUTO;
94 	res->start = 0;
95 	res->end = 0;
96 
97 	/* ??? rule->flags restricted to 8 bits, all tests bogus ??? */
98 	if (!(rule->flags & IORESOURCE_MEM_WRITEABLE))
99 		res->flags |= IORESOURCE_READONLY;
100 	if (rule->flags & IORESOURCE_MEM_RANGELENGTH)
101 		res->flags |= IORESOURCE_RANGELENGTH;
102 	if (rule->flags & IORESOURCE_MEM_SHADOWABLE)
103 		res->flags |= IORESOURCE_SHADOWABLE;
104 
105 	if (!rule->size) {
106 		res->flags |= IORESOURCE_DISABLED;
107 		pnp_dbg(&dev->dev, "  mem %d disabled\n", idx);
108 		goto __add;
109 	}
110 
111 	res->start = rule->min;
112 	res->end = res->start + rule->size - 1;
113 
114 	while (!pnp_check_mem(dev, res)) {
115 		res->start += rule->align;
116 		res->end = res->start + rule->size - 1;
117 		if (res->start > rule->max || !rule->align) {
118 			pnp_dbg(&dev->dev, "  couldn't assign mem %d "
119 				"(min %#llx max %#llx)\n", idx,
120 				(unsigned long long) rule->min,
121 				(unsigned long long) rule->max);
122 			return -EBUSY;
123 		}
124 	}
125 
126 __add:
127 	pnp_add_mem_resource(dev, res->start, res->end, res->flags);
128 	return 0;
129 }
130 
131 static int pnp_assign_irq(struct pnp_dev *dev, struct pnp_irq *rule, int idx)
132 {
133 	struct resource *res, local_res;
134 	int i;
135 
136 	/* IRQ priority: this table is good for i386 */
137 	static unsigned short xtab[16] = {
138 		5, 10, 11, 12, 9, 14, 15, 7, 3, 4, 13, 0, 1, 6, 8, 2
139 	};
140 
141 	res = pnp_find_resource(dev, rule->flags, IORESOURCE_IRQ, idx);
142 	if (res) {
143 		pnp_dbg(&dev->dev, "  irq %d already set to %d flags %#lx\n",
144 			idx, (int) res->start, res->flags);
145 		return 0;
146 	}
147 
148 	res = &local_res;
149 	res->flags = rule->flags | IORESOURCE_AUTO;
150 	res->start = -1;
151 	res->end = -1;
152 
153 	if (bitmap_empty(rule->map.bits, PNP_IRQ_NR)) {
154 		res->flags |= IORESOURCE_DISABLED;
155 		pnp_dbg(&dev->dev, "  irq %d disabled\n", idx);
156 		goto __add;
157 	}
158 
159 	/* TBD: need check for >16 IRQ */
160 	res->start = find_next_bit(rule->map.bits, PNP_IRQ_NR, 16);
161 	if (res->start < PNP_IRQ_NR) {
162 		res->end = res->start;
163 		goto __add;
164 	}
165 	for (i = 0; i < 16; i++) {
166 		if (test_bit(xtab[i], rule->map.bits)) {
167 			res->start = res->end = xtab[i];
168 			if (pnp_check_irq(dev, res))
169 				goto __add;
170 		}
171 	}
172 
173 	if (rule->flags & IORESOURCE_IRQ_OPTIONAL) {
174 		res->start = -1;
175 		res->end = -1;
176 		res->flags |= IORESOURCE_DISABLED;
177 		pnp_dbg(&dev->dev, "  irq %d disabled (optional)\n", idx);
178 		goto __add;
179 	}
180 
181 	pnp_dbg(&dev->dev, "  couldn't assign irq %d\n", idx);
182 	return -EBUSY;
183 
184 __add:
185 	pnp_add_irq_resource(dev, res->start, res->flags);
186 	return 0;
187 }
188 
189 #ifdef CONFIG_ISA_DMA_API
190 static int pnp_assign_dma(struct pnp_dev *dev, struct pnp_dma *rule, int idx)
191 {
192 	struct resource *res, local_res;
193 	int i;
194 
195 	/* DMA priority: this table is good for i386 */
196 	static unsigned short xtab[8] = {
197 		1, 3, 5, 6, 7, 0, 2, 4
198 	};
199 
200 	res = pnp_find_resource(dev, rule->flags, IORESOURCE_DMA, idx);
201 	if (res) {
202 		pnp_dbg(&dev->dev, "  dma %d already set to %d flags %#lx\n",
203 			idx, (int) res->start, res->flags);
204 		return 0;
205 	}
206 
207 	res = &local_res;
208 	res->flags = rule->flags | IORESOURCE_AUTO;
209 	res->start = -1;
210 	res->end = -1;
211 
212 	if (!rule->map) {
213 		res->flags |= IORESOURCE_DISABLED;
214 		pnp_dbg(&dev->dev, "  dma %d disabled\n", idx);
215 		goto __add;
216 	}
217 
218 	for (i = 0; i < 8; i++) {
219 		if (rule->map & (1 << xtab[i])) {
220 			res->start = res->end = xtab[i];
221 			if (pnp_check_dma(dev, res))
222 				goto __add;
223 		}
224 	}
225 
226 	pnp_dbg(&dev->dev, "  couldn't assign dma %d\n", idx);
227 	return -EBUSY;
228 
229 __add:
230 	pnp_add_dma_resource(dev, res->start, res->flags);
231 	return 0;
232 }
233 #endif /* CONFIG_ISA_DMA_API */
234 
235 void pnp_init_resources(struct pnp_dev *dev)
236 {
237 	pnp_free_resources(dev);
238 }
239 
240 static void pnp_clean_resource_table(struct pnp_dev *dev)
241 {
242 	struct pnp_resource *pnp_res, *tmp;
243 
244 	list_for_each_entry_safe(pnp_res, tmp, &dev->resources, list) {
245 		if (pnp_res->res.flags & IORESOURCE_AUTO)
246 			pnp_free_resource(pnp_res);
247 	}
248 }
249 
250 /**
251  * pnp_assign_resources - assigns resources to the device based on the specified dependent number
252  * @dev: pointer to the desired device
253  * @set: the dependent function number
254  */
255 static int pnp_assign_resources(struct pnp_dev *dev, int set)
256 {
257 	struct pnp_option *option;
258 	int nport = 0, nmem = 0, nirq = 0;
259 	int ndma __maybe_unused = 0;
260 	int ret = 0;
261 
262 	pnp_dbg(&dev->dev, "pnp_assign_resources, try dependent set %d\n", set);
263 	mutex_lock(&pnp_res_mutex);
264 	pnp_clean_resource_table(dev);
265 
266 	list_for_each_entry(option, &dev->options, list) {
267 		if (pnp_option_is_dependent(option) &&
268 		    pnp_option_set(option) != set)
269 				continue;
270 
271 		switch (option->type) {
272 		case IORESOURCE_IO:
273 			ret = pnp_assign_port(dev, &option->u.port, nport++);
274 			break;
275 		case IORESOURCE_MEM:
276 			ret = pnp_assign_mem(dev, &option->u.mem, nmem++);
277 			break;
278 		case IORESOURCE_IRQ:
279 			ret = pnp_assign_irq(dev, &option->u.irq, nirq++);
280 			break;
281 #ifdef CONFIG_ISA_DMA_API
282 		case IORESOURCE_DMA:
283 			ret = pnp_assign_dma(dev, &option->u.dma, ndma++);
284 			break;
285 #endif
286 		default:
287 			ret = -EINVAL;
288 			break;
289 		}
290 		if (ret < 0)
291 			break;
292 	}
293 
294 	mutex_unlock(&pnp_res_mutex);
295 	if (ret < 0) {
296 		pnp_dbg(&dev->dev, "pnp_assign_resources failed (%d)\n", ret);
297 		pnp_clean_resource_table(dev);
298 	} else
299 		dbg_pnp_show_resources(dev, "pnp_assign_resources succeeded");
300 	return ret;
301 }
302 
303 /**
304  * pnp_auto_config_dev - automatically assigns resources to a device
305  * @dev: pointer to the desired device
306  */
307 int pnp_auto_config_dev(struct pnp_dev *dev)
308 {
309 	int i, ret;
310 
311 	if (!pnp_can_configure(dev)) {
312 		pnp_dbg(&dev->dev, "configuration not supported\n");
313 		return -ENODEV;
314 	}
315 
316 	ret = pnp_assign_resources(dev, 0);
317 	if (ret == 0)
318 		return 0;
319 
320 	for (i = 1; i < dev->num_dependent_sets; i++) {
321 		ret = pnp_assign_resources(dev, i);
322 		if (ret == 0)
323 			return 0;
324 	}
325 
326 	dev_err(&dev->dev, "unable to assign resources\n");
327 	return ret;
328 }
329 
330 /**
331  * pnp_start_dev - low-level start of the PnP device
332  * @dev: pointer to the desired device
333  *
334  * assumes that resources have already been allocated
335  */
336 int pnp_start_dev(struct pnp_dev *dev)
337 {
338 	if (!pnp_can_write(dev)) {
339 		pnp_dbg(&dev->dev, "activation not supported\n");
340 		return -EINVAL;
341 	}
342 
343 	dbg_pnp_show_resources(dev, "pnp_start_dev");
344 	if (dev->protocol->set(dev) < 0) {
345 		dev_err(&dev->dev, "activation failed\n");
346 		return -EIO;
347 	}
348 
349 	dev_info(&dev->dev, "activated\n");
350 	return 0;
351 }
352 
353 /**
354  * pnp_stop_dev - low-level disable of the PnP device
355  * @dev: pointer to the desired device
356  *
357  * does not free resources
358  */
359 int pnp_stop_dev(struct pnp_dev *dev)
360 {
361 	if (!pnp_can_disable(dev)) {
362 		pnp_dbg(&dev->dev, "disabling not supported\n");
363 		return -EINVAL;
364 	}
365 	if (dev->protocol->disable(dev) < 0) {
366 		dev_err(&dev->dev, "disable failed\n");
367 		return -EIO;
368 	}
369 
370 	dev_info(&dev->dev, "disabled\n");
371 	return 0;
372 }
373 
374 /**
375  * pnp_activate_dev - activates a PnP device for use
376  * @dev: pointer to the desired device
377  *
378  * does not validate or set resources so be careful.
379  */
380 int pnp_activate_dev(struct pnp_dev *dev)
381 {
382 	int error;
383 
384 	if (dev->active)
385 		return 0;
386 
387 	/* ensure resources are allocated */
388 	if (pnp_auto_config_dev(dev))
389 		return -EBUSY;
390 
391 	error = pnp_start_dev(dev);
392 	if (error)
393 		return error;
394 
395 	dev->active = 1;
396 	return 0;
397 }
398 
399 /**
400  * pnp_disable_dev - disables device
401  * @dev: pointer to the desired device
402  *
403  * inform the correct pnp protocol so that resources can be used by other devices
404  */
405 int pnp_disable_dev(struct pnp_dev *dev)
406 {
407 	int error;
408 
409 	if (!dev->active)
410 		return 0;
411 
412 	error = pnp_stop_dev(dev);
413 	if (error)
414 		return error;
415 
416 	dev->active = 0;
417 
418 	/* release the resources so that other devices can use them */
419 	mutex_lock(&pnp_res_mutex);
420 	pnp_clean_resource_table(dev);
421 	mutex_unlock(&pnp_res_mutex);
422 
423 	return 0;
424 }
425 
426 EXPORT_SYMBOL(pnp_start_dev);
427 EXPORT_SYMBOL(pnp_stop_dev);
428 EXPORT_SYMBOL(pnp_activate_dev);
429 EXPORT_SYMBOL(pnp_disable_dev);
430