xref: /linux/drivers/pnp/manager.c (revision c4ee0af3fa0dc65f690fc908f02b8355f9576ea0)
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_CACHEABLE)
101 		res->flags |= IORESOURCE_CACHEABLE;
102 	if (rule->flags & IORESOURCE_MEM_RANGELENGTH)
103 		res->flags |= IORESOURCE_RANGELENGTH;
104 	if (rule->flags & IORESOURCE_MEM_SHADOWABLE)
105 		res->flags |= IORESOURCE_SHADOWABLE;
106 
107 	if (!rule->size) {
108 		res->flags |= IORESOURCE_DISABLED;
109 		pnp_dbg(&dev->dev, "  mem %d disabled\n", idx);
110 		goto __add;
111 	}
112 
113 	res->start = rule->min;
114 	res->end = res->start + rule->size - 1;
115 
116 	while (!pnp_check_mem(dev, res)) {
117 		res->start += rule->align;
118 		res->end = res->start + rule->size - 1;
119 		if (res->start > rule->max || !rule->align) {
120 			pnp_dbg(&dev->dev, "  couldn't assign mem %d "
121 				"(min %#llx max %#llx)\n", idx,
122 				(unsigned long long) rule->min,
123 				(unsigned long long) rule->max);
124 			return -EBUSY;
125 		}
126 	}
127 
128 __add:
129 	pnp_add_mem_resource(dev, res->start, res->end, res->flags);
130 	return 0;
131 }
132 
133 static int pnp_assign_irq(struct pnp_dev *dev, struct pnp_irq *rule, int idx)
134 {
135 	struct resource *res, local_res;
136 	int i;
137 
138 	/* IRQ priority: this table is good for i386 */
139 	static unsigned short xtab[16] = {
140 		5, 10, 11, 12, 9, 14, 15, 7, 3, 4, 13, 0, 1, 6, 8, 2
141 	};
142 
143 	res = pnp_find_resource(dev, rule->flags, IORESOURCE_IRQ, idx);
144 	if (res) {
145 		pnp_dbg(&dev->dev, "  irq %d already set to %d flags %#lx\n",
146 			idx, (int) res->start, res->flags);
147 		return 0;
148 	}
149 
150 	res = &local_res;
151 	res->flags = rule->flags | IORESOURCE_AUTO;
152 	res->start = -1;
153 	res->end = -1;
154 
155 	if (bitmap_empty(rule->map.bits, PNP_IRQ_NR)) {
156 		res->flags |= IORESOURCE_DISABLED;
157 		pnp_dbg(&dev->dev, "  irq %d disabled\n", idx);
158 		goto __add;
159 	}
160 
161 	/* TBD: need check for >16 IRQ */
162 	res->start = find_next_bit(rule->map.bits, PNP_IRQ_NR, 16);
163 	if (res->start < PNP_IRQ_NR) {
164 		res->end = res->start;
165 		goto __add;
166 	}
167 	for (i = 0; i < 16; i++) {
168 		if (test_bit(xtab[i], rule->map.bits)) {
169 			res->start = res->end = xtab[i];
170 			if (pnp_check_irq(dev, res))
171 				goto __add;
172 		}
173 	}
174 
175 	if (rule->flags & IORESOURCE_IRQ_OPTIONAL) {
176 		res->start = -1;
177 		res->end = -1;
178 		res->flags |= IORESOURCE_DISABLED;
179 		pnp_dbg(&dev->dev, "  irq %d disabled (optional)\n", idx);
180 		goto __add;
181 	}
182 
183 	pnp_dbg(&dev->dev, "  couldn't assign irq %d\n", idx);
184 	return -EBUSY;
185 
186 __add:
187 	pnp_add_irq_resource(dev, res->start, res->flags);
188 	return 0;
189 }
190 
191 #ifdef CONFIG_ISA_DMA_API
192 static int pnp_assign_dma(struct pnp_dev *dev, struct pnp_dma *rule, int idx)
193 {
194 	struct resource *res, local_res;
195 	int i;
196 
197 	/* DMA priority: this table is good for i386 */
198 	static unsigned short xtab[8] = {
199 		1, 3, 5, 6, 7, 0, 2, 4
200 	};
201 
202 	res = pnp_find_resource(dev, rule->flags, IORESOURCE_DMA, idx);
203 	if (res) {
204 		pnp_dbg(&dev->dev, "  dma %d already set to %d flags %#lx\n",
205 			idx, (int) res->start, res->flags);
206 		return 0;
207 	}
208 
209 	res = &local_res;
210 	res->flags = rule->flags | IORESOURCE_AUTO;
211 	res->start = -1;
212 	res->end = -1;
213 
214 	if (!rule->map) {
215 		res->flags |= IORESOURCE_DISABLED;
216 		pnp_dbg(&dev->dev, "  dma %d disabled\n", idx);
217 		goto __add;
218 	}
219 
220 	for (i = 0; i < 8; i++) {
221 		if (rule->map & (1 << xtab[i])) {
222 			res->start = res->end = xtab[i];
223 			if (pnp_check_dma(dev, res))
224 				goto __add;
225 		}
226 	}
227 
228 	pnp_dbg(&dev->dev, "  couldn't assign dma %d\n", idx);
229 	return -EBUSY;
230 
231 __add:
232 	pnp_add_dma_resource(dev, res->start, res->flags);
233 	return 0;
234 }
235 #endif /* CONFIG_ISA_DMA_API */
236 
237 void pnp_init_resources(struct pnp_dev *dev)
238 {
239 	pnp_free_resources(dev);
240 }
241 
242 static void pnp_clean_resource_table(struct pnp_dev *dev)
243 {
244 	struct pnp_resource *pnp_res, *tmp;
245 
246 	list_for_each_entry_safe(pnp_res, tmp, &dev->resources, list) {
247 		if (pnp_res->res.flags & IORESOURCE_AUTO)
248 			pnp_free_resource(pnp_res);
249 	}
250 }
251 
252 /**
253  * pnp_assign_resources - assigns resources to the device based on the specified dependent number
254  * @dev: pointer to the desired device
255  * @set: the dependent function number
256  */
257 static int pnp_assign_resources(struct pnp_dev *dev, int set)
258 {
259 	struct pnp_option *option;
260 	int nport = 0, nmem = 0, nirq = 0;
261 	int ndma __maybe_unused = 0;
262 	int ret = 0;
263 
264 	pnp_dbg(&dev->dev, "pnp_assign_resources, try dependent set %d\n", set);
265 	mutex_lock(&pnp_res_mutex);
266 	pnp_clean_resource_table(dev);
267 
268 	list_for_each_entry(option, &dev->options, list) {
269 		if (pnp_option_is_dependent(option) &&
270 		    pnp_option_set(option) != set)
271 				continue;
272 
273 		switch (option->type) {
274 		case IORESOURCE_IO:
275 			ret = pnp_assign_port(dev, &option->u.port, nport++);
276 			break;
277 		case IORESOURCE_MEM:
278 			ret = pnp_assign_mem(dev, &option->u.mem, nmem++);
279 			break;
280 		case IORESOURCE_IRQ:
281 			ret = pnp_assign_irq(dev, &option->u.irq, nirq++);
282 			break;
283 #ifdef CONFIG_ISA_DMA_API
284 		case IORESOURCE_DMA:
285 			ret = pnp_assign_dma(dev, &option->u.dma, ndma++);
286 			break;
287 #endif
288 		default:
289 			ret = -EINVAL;
290 			break;
291 		}
292 		if (ret < 0)
293 			break;
294 	}
295 
296 	mutex_unlock(&pnp_res_mutex);
297 	if (ret < 0) {
298 		pnp_dbg(&dev->dev, "pnp_assign_resources failed (%d)\n", ret);
299 		pnp_clean_resource_table(dev);
300 	} else
301 		dbg_pnp_show_resources(dev, "pnp_assign_resources succeeded");
302 	return ret;
303 }
304 
305 /**
306  * pnp_auto_config_dev - automatically assigns resources to a device
307  * @dev: pointer to the desired device
308  */
309 int pnp_auto_config_dev(struct pnp_dev *dev)
310 {
311 	int i, ret;
312 
313 	if (!pnp_can_configure(dev)) {
314 		pnp_dbg(&dev->dev, "configuration not supported\n");
315 		return -ENODEV;
316 	}
317 
318 	ret = pnp_assign_resources(dev, 0);
319 	if (ret == 0)
320 		return 0;
321 
322 	for (i = 1; i < dev->num_dependent_sets; i++) {
323 		ret = pnp_assign_resources(dev, i);
324 		if (ret == 0)
325 			return 0;
326 	}
327 
328 	dev_err(&dev->dev, "unable to assign resources\n");
329 	return ret;
330 }
331 
332 /**
333  * pnp_start_dev - low-level start of the PnP device
334  * @dev: pointer to the desired device
335  *
336  * assumes that resources have already been allocated
337  */
338 int pnp_start_dev(struct pnp_dev *dev)
339 {
340 	if (!pnp_can_write(dev)) {
341 		pnp_dbg(&dev->dev, "activation not supported\n");
342 		return -EINVAL;
343 	}
344 
345 	dbg_pnp_show_resources(dev, "pnp_start_dev");
346 	if (dev->protocol->set(dev) < 0) {
347 		dev_err(&dev->dev, "activation failed\n");
348 		return -EIO;
349 	}
350 
351 	dev_info(&dev->dev, "activated\n");
352 	return 0;
353 }
354 
355 /**
356  * pnp_stop_dev - low-level disable of the PnP device
357  * @dev: pointer to the desired device
358  *
359  * does not free resources
360  */
361 int pnp_stop_dev(struct pnp_dev *dev)
362 {
363 	if (!pnp_can_disable(dev)) {
364 		pnp_dbg(&dev->dev, "disabling not supported\n");
365 		return -EINVAL;
366 	}
367 	if (dev->protocol->disable(dev) < 0) {
368 		dev_err(&dev->dev, "disable failed\n");
369 		return -EIO;
370 	}
371 
372 	dev_info(&dev->dev, "disabled\n");
373 	return 0;
374 }
375 
376 /**
377  * pnp_activate_dev - activates a PnP device for use
378  * @dev: pointer to the desired device
379  *
380  * does not validate or set resources so be careful.
381  */
382 int pnp_activate_dev(struct pnp_dev *dev)
383 {
384 	int error;
385 
386 	if (dev->active)
387 		return 0;
388 
389 	/* ensure resources are allocated */
390 	if (pnp_auto_config_dev(dev))
391 		return -EBUSY;
392 
393 	error = pnp_start_dev(dev);
394 	if (error)
395 		return error;
396 
397 	dev->active = 1;
398 	return 0;
399 }
400 
401 /**
402  * pnp_disable_dev - disables device
403  * @dev: pointer to the desired device
404  *
405  * inform the correct pnp protocol so that resources can be used by other devices
406  */
407 int pnp_disable_dev(struct pnp_dev *dev)
408 {
409 	int error;
410 
411 	if (!dev->active)
412 		return 0;
413 
414 	error = pnp_stop_dev(dev);
415 	if (error)
416 		return error;
417 
418 	dev->active = 0;
419 
420 	/* release the resources so that other devices can use them */
421 	mutex_lock(&pnp_res_mutex);
422 	pnp_clean_resource_table(dev);
423 	mutex_unlock(&pnp_res_mutex);
424 
425 	return 0;
426 }
427 
428 EXPORT_SYMBOL(pnp_start_dev);
429 EXPORT_SYMBOL(pnp_stop_dev);
430 EXPORT_SYMBOL(pnp_activate_dev);
431 EXPORT_SYMBOL(pnp_disable_dev);
432