xref: /openbmc/linux/drivers/pnp/manager.c (revision 8fa5723aa7e053d498336b48448b292fc2e0458b)
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/slab.h>
16 #include <linux/bitmap.h>
17 #include <linux/mutex.h>
18 #include "base.h"
19 
20 DEFINE_MUTEX(pnp_res_mutex);
21 
22 static int pnp_assign_port(struct pnp_dev *dev, struct pnp_port *rule, int idx)
23 {
24 	struct resource *res, local_res;
25 
26 	res = pnp_get_resource(dev, IORESOURCE_IO, idx);
27 	if (res) {
28 		pnp_dbg(&dev->dev, "  io %d already set to %#llx-%#llx "
29 			"flags %#lx\n", idx, (unsigned long long) res->start,
30 			(unsigned long long) res->end, res->flags);
31 		return 0;
32 	}
33 
34 	res = &local_res;
35 	res->flags = rule->flags | IORESOURCE_AUTO;
36 	res->start = 0;
37 	res->end = 0;
38 
39 	if (!rule->size) {
40 		res->flags |= IORESOURCE_DISABLED;
41 		pnp_dbg(&dev->dev, "  io %d disabled\n", idx);
42 		goto __add;
43 	}
44 
45 	res->start = rule->min;
46 	res->end = res->start + rule->size - 1;
47 
48 	while (!pnp_check_port(dev, res)) {
49 		res->start += rule->align;
50 		res->end = res->start + rule->size - 1;
51 		if (res->start > rule->max || !rule->align) {
52 			pnp_dbg(&dev->dev, "  couldn't assign io %d "
53 				"(min %#llx max %#llx)\n", idx,
54 				(unsigned long long) rule->min,
55 				(unsigned long long) rule->max);
56 			return -EBUSY;
57 		}
58 	}
59 
60 __add:
61 	pnp_add_io_resource(dev, res->start, res->end, res->flags);
62 	return 0;
63 }
64 
65 static int pnp_assign_mem(struct pnp_dev *dev, struct pnp_mem *rule, int idx)
66 {
67 	struct resource *res, local_res;
68 
69 	res = pnp_get_resource(dev, IORESOURCE_MEM, idx);
70 	if (res) {
71 		pnp_dbg(&dev->dev, "  mem %d already set to %#llx-%#llx "
72 			"flags %#lx\n", idx, (unsigned long long) res->start,
73 			(unsigned long long) res->end, res->flags);
74 		return 0;
75 	}
76 
77 	res = &local_res;
78 	res->flags = rule->flags | IORESOURCE_AUTO;
79 	res->start = 0;
80 	res->end = 0;
81 
82 	if (!(rule->flags & IORESOURCE_MEM_WRITEABLE))
83 		res->flags |= IORESOURCE_READONLY;
84 	if (rule->flags & IORESOURCE_MEM_CACHEABLE)
85 		res->flags |= IORESOURCE_CACHEABLE;
86 	if (rule->flags & IORESOURCE_MEM_RANGELENGTH)
87 		res->flags |= IORESOURCE_RANGELENGTH;
88 	if (rule->flags & IORESOURCE_MEM_SHADOWABLE)
89 		res->flags |= IORESOURCE_SHADOWABLE;
90 
91 	if (!rule->size) {
92 		res->flags |= IORESOURCE_DISABLED;
93 		pnp_dbg(&dev->dev, "  mem %d disabled\n", idx);
94 		goto __add;
95 	}
96 
97 	res->start = rule->min;
98 	res->end = res->start + rule->size - 1;
99 
100 	while (!pnp_check_mem(dev, res)) {
101 		res->start += rule->align;
102 		res->end = res->start + rule->size - 1;
103 		if (res->start > rule->max || !rule->align) {
104 			pnp_dbg(&dev->dev, "  couldn't assign mem %d "
105 				"(min %#llx max %#llx)\n", idx,
106 				(unsigned long long) rule->min,
107 				(unsigned long long) rule->max);
108 			return -EBUSY;
109 		}
110 	}
111 
112 __add:
113 	pnp_add_mem_resource(dev, res->start, res->end, res->flags);
114 	return 0;
115 }
116 
117 static int pnp_assign_irq(struct pnp_dev *dev, struct pnp_irq *rule, int idx)
118 {
119 	struct resource *res, local_res;
120 	int i;
121 
122 	/* IRQ priority: this table is good for i386 */
123 	static unsigned short xtab[16] = {
124 		5, 10, 11, 12, 9, 14, 15, 7, 3, 4, 13, 0, 1, 6, 8, 2
125 	};
126 
127 	res = pnp_get_resource(dev, IORESOURCE_IRQ, idx);
128 	if (res) {
129 		pnp_dbg(&dev->dev, "  irq %d already set to %d flags %#lx\n",
130 			idx, (int) res->start, res->flags);
131 		return 0;
132 	}
133 
134 	res = &local_res;
135 	res->flags = rule->flags | IORESOURCE_AUTO;
136 	res->start = -1;
137 	res->end = -1;
138 
139 	if (bitmap_empty(rule->map.bits, PNP_IRQ_NR)) {
140 		res->flags |= IORESOURCE_DISABLED;
141 		pnp_dbg(&dev->dev, "  irq %d disabled\n", idx);
142 		goto __add;
143 	}
144 
145 	/* TBD: need check for >16 IRQ */
146 	res->start = find_next_bit(rule->map.bits, PNP_IRQ_NR, 16);
147 	if (res->start < PNP_IRQ_NR) {
148 		res->end = res->start;
149 		goto __add;
150 	}
151 	for (i = 0; i < 16; i++) {
152 		if (test_bit(xtab[i], rule->map.bits)) {
153 			res->start = res->end = xtab[i];
154 			if (pnp_check_irq(dev, res))
155 				goto __add;
156 		}
157 	}
158 
159 	if (rule->flags & IORESOURCE_IRQ_OPTIONAL) {
160 		res->start = -1;
161 		res->end = -1;
162 		res->flags |= IORESOURCE_DISABLED;
163 		pnp_dbg(&dev->dev, "  irq %d disabled (optional)\n", idx);
164 		goto __add;
165 	}
166 
167 	pnp_dbg(&dev->dev, "  couldn't assign irq %d\n", idx);
168 	return -EBUSY;
169 
170 __add:
171 	pnp_add_irq_resource(dev, res->start, res->flags);
172 	return 0;
173 }
174 
175 static int pnp_assign_dma(struct pnp_dev *dev, struct pnp_dma *rule, int idx)
176 {
177 	struct resource *res, local_res;
178 	int i;
179 
180 	/* DMA priority: this table is good for i386 */
181 	static unsigned short xtab[8] = {
182 		1, 3, 5, 6, 7, 0, 2, 4
183 	};
184 
185 	res = pnp_get_resource(dev, IORESOURCE_DMA, idx);
186 	if (res) {
187 		pnp_dbg(&dev->dev, "  dma %d already set to %d flags %#lx\n",
188 			idx, (int) res->start, res->flags);
189 		return 0;
190 	}
191 
192 	res = &local_res;
193 	res->flags = rule->flags | IORESOURCE_AUTO;
194 	res->start = -1;
195 	res->end = -1;
196 
197 	for (i = 0; i < 8; i++) {
198 		if (rule->map & (1 << xtab[i])) {
199 			res->start = res->end = xtab[i];
200 			if (pnp_check_dma(dev, res))
201 				goto __add;
202 		}
203 	}
204 #ifdef MAX_DMA_CHANNELS
205 	res->start = res->end = MAX_DMA_CHANNELS;
206 #endif
207 	res->flags |= IORESOURCE_DISABLED;
208 	pnp_dbg(&dev->dev, "  disable dma %d\n", idx);
209 
210 __add:
211 	pnp_add_dma_resource(dev, res->start, res->flags);
212 	return 0;
213 }
214 
215 void pnp_init_resources(struct pnp_dev *dev)
216 {
217 	pnp_free_resources(dev);
218 }
219 
220 static void pnp_clean_resource_table(struct pnp_dev *dev)
221 {
222 	struct pnp_resource *pnp_res, *tmp;
223 
224 	list_for_each_entry_safe(pnp_res, tmp, &dev->resources, list) {
225 		if (pnp_res->res.flags & IORESOURCE_AUTO)
226 			pnp_free_resource(pnp_res);
227 	}
228 }
229 
230 /**
231  * pnp_assign_resources - assigns resources to the device based on the specified dependent number
232  * @dev: pointer to the desired device
233  * @set: the dependent function number
234  */
235 static int pnp_assign_resources(struct pnp_dev *dev, int set)
236 {
237 	struct pnp_option *option;
238 	int nport = 0, nmem = 0, nirq = 0, ndma = 0;
239 	int ret = 0;
240 
241 	pnp_dbg(&dev->dev, "pnp_assign_resources, try dependent set %d\n", set);
242 	mutex_lock(&pnp_res_mutex);
243 	pnp_clean_resource_table(dev);
244 
245 	list_for_each_entry(option, &dev->options, list) {
246 		if (pnp_option_is_dependent(option) &&
247 		    pnp_option_set(option) != set)
248 				continue;
249 
250 		switch (option->type) {
251 		case IORESOURCE_IO:
252 			ret = pnp_assign_port(dev, &option->u.port, nport++);
253 			break;
254 		case IORESOURCE_MEM:
255 			ret = pnp_assign_mem(dev, &option->u.mem, nmem++);
256 			break;
257 		case IORESOURCE_IRQ:
258 			ret = pnp_assign_irq(dev, &option->u.irq, nirq++);
259 			break;
260 		case IORESOURCE_DMA:
261 			ret = pnp_assign_dma(dev, &option->u.dma, ndma++);
262 			break;
263 		default:
264 			ret = -EINVAL;
265 			break;
266 		}
267 		if (ret < 0)
268 			break;
269 	}
270 
271 	mutex_unlock(&pnp_res_mutex);
272 	if (ret < 0) {
273 		pnp_dbg(&dev->dev, "pnp_assign_resources failed (%d)\n", ret);
274 		pnp_clean_resource_table(dev);
275 	} else
276 		dbg_pnp_show_resources(dev, "pnp_assign_resources succeeded");
277 	return ret;
278 }
279 
280 /**
281  * pnp_auto_config_dev - automatically assigns resources to a device
282  * @dev: pointer to the desired device
283  */
284 int pnp_auto_config_dev(struct pnp_dev *dev)
285 {
286 	int i, ret;
287 
288 	if (!pnp_can_configure(dev)) {
289 		pnp_dbg(&dev->dev, "configuration not supported\n");
290 		return -ENODEV;
291 	}
292 
293 	ret = pnp_assign_resources(dev, 0);
294 	if (ret == 0)
295 		return 0;
296 
297 	for (i = 1; i < dev->num_dependent_sets; i++) {
298 		ret = pnp_assign_resources(dev, i);
299 		if (ret == 0)
300 			return 0;
301 	}
302 
303 	dev_err(&dev->dev, "unable to assign resources\n");
304 	return ret;
305 }
306 
307 /**
308  * pnp_start_dev - low-level start of the PnP device
309  * @dev: pointer to the desired device
310  *
311  * assumes that resources have already been allocated
312  */
313 int pnp_start_dev(struct pnp_dev *dev)
314 {
315 	if (!pnp_can_write(dev)) {
316 		pnp_dbg(&dev->dev, "activation not supported\n");
317 		return -EINVAL;
318 	}
319 
320 	dbg_pnp_show_resources(dev, "pnp_start_dev");
321 	if (dev->protocol->set(dev) < 0) {
322 		dev_err(&dev->dev, "activation failed\n");
323 		return -EIO;
324 	}
325 
326 	dev_info(&dev->dev, "activated\n");
327 	return 0;
328 }
329 
330 /**
331  * pnp_stop_dev - low-level disable of the PnP device
332  * @dev: pointer to the desired device
333  *
334  * does not free resources
335  */
336 int pnp_stop_dev(struct pnp_dev *dev)
337 {
338 	if (!pnp_can_disable(dev)) {
339 		pnp_dbg(&dev->dev, "disabling not supported\n");
340 		return -EINVAL;
341 	}
342 	if (dev->protocol->disable(dev) < 0) {
343 		dev_err(&dev->dev, "disable failed\n");
344 		return -EIO;
345 	}
346 
347 	dev_info(&dev->dev, "disabled\n");
348 	return 0;
349 }
350 
351 /**
352  * pnp_activate_dev - activates a PnP device for use
353  * @dev: pointer to the desired device
354  *
355  * does not validate or set resources so be careful.
356  */
357 int pnp_activate_dev(struct pnp_dev *dev)
358 {
359 	int error;
360 
361 	if (dev->active)
362 		return 0;
363 
364 	/* ensure resources are allocated */
365 	if (pnp_auto_config_dev(dev))
366 		return -EBUSY;
367 
368 	error = pnp_start_dev(dev);
369 	if (error)
370 		return error;
371 
372 	dev->active = 1;
373 	return 0;
374 }
375 
376 /**
377  * pnp_disable_dev - disables device
378  * @dev: pointer to the desired device
379  *
380  * inform the correct pnp protocol so that resources can be used by other devices
381  */
382 int pnp_disable_dev(struct pnp_dev *dev)
383 {
384 	int error;
385 
386 	if (!dev->active)
387 		return 0;
388 
389 	error = pnp_stop_dev(dev);
390 	if (error)
391 		return error;
392 
393 	dev->active = 0;
394 
395 	/* release the resources so that other devices can use them */
396 	mutex_lock(&pnp_res_mutex);
397 	pnp_clean_resource_table(dev);
398 	mutex_unlock(&pnp_res_mutex);
399 
400 	return 0;
401 }
402 
403 EXPORT_SYMBOL(pnp_start_dev);
404 EXPORT_SYMBOL(pnp_stop_dev);
405 EXPORT_SYMBOL(pnp_activate_dev);
406 EXPORT_SYMBOL(pnp_disable_dev);
407