xref: /openbmc/linux/drivers/eisa/eisa-bus.c (revision d9fd5a71)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * EISA bus support functions for sysfs.
4  *
5  * (C) 2002, 2003 Marc Zyngier <maz@wild-wind.fr.eu.org>
6  */
7 
8 #include <linux/kernel.h>
9 #include <linux/device.h>
10 #include <linux/eisa.h>
11 #include <linux/module.h>
12 #include <linux/moduleparam.h>
13 #include <linux/init.h>
14 #include <linux/slab.h>
15 #include <linux/ioport.h>
16 #include <asm/io.h>
17 
18 #define SLOT_ADDRESS(r,n) (r->bus_base_addr + (0x1000 * n))
19 
20 #define EISA_DEVINFO(i,s) { .id = { .sig = i }, .name = s }
21 
22 struct eisa_device_info {
23 	struct eisa_device_id id;
24 	char name[50];
25 };
26 
27 #ifdef CONFIG_EISA_NAMES
28 static struct eisa_device_info __initdata eisa_table[] = {
29 #include "devlist.h"
30 };
31 #define EISA_INFOS (sizeof (eisa_table) / (sizeof (struct eisa_device_info)))
32 #endif
33 
34 #define EISA_MAX_FORCED_DEV 16
35 
36 static int enable_dev[EISA_MAX_FORCED_DEV];
37 static unsigned int enable_dev_count;
38 static int disable_dev[EISA_MAX_FORCED_DEV];
39 static unsigned int disable_dev_count;
40 
41 static int is_forced_dev(int *forced_tab,
42 			 int forced_count,
43 			 struct eisa_root_device *root,
44 			 struct eisa_device *edev)
45 {
46 	int i, x;
47 
48 	for (i = 0; i < forced_count; i++) {
49 		x = (root->bus_nr << 8) | edev->slot;
50 		if (forced_tab[i] == x)
51 			return 1;
52 	}
53 
54 	return 0;
55 }
56 
57 static void __init eisa_name_device(struct eisa_device *edev)
58 {
59 #ifdef CONFIG_EISA_NAMES
60 	int i;
61 	for (i = 0; i < EISA_INFOS; i++) {
62 		if (!strcmp(edev->id.sig, eisa_table[i].id.sig)) {
63 			strlcpy(edev->pretty_name,
64 				eisa_table[i].name,
65 				sizeof(edev->pretty_name));
66 			return;
67 		}
68 	}
69 
70 	/* No name was found */
71 	sprintf(edev->pretty_name, "EISA device %.7s", edev->id.sig);
72 #endif
73 }
74 
75 static char __init *decode_eisa_sig(unsigned long addr)
76 {
77 	static char sig_str[EISA_SIG_LEN];
78 	u8 sig[4];
79 	u16 rev;
80 	int i;
81 
82 	for (i = 0; i < 4; i++) {
83 #ifdef CONFIG_EISA_VLB_PRIMING
84 		/*
85 		 * This ugly stuff is used to wake up VL-bus cards
86 		 * (AHA-284x is the only known example), so we can
87 		 * read the EISA id.
88 		 *
89 		 * Thankfully, this only exists on x86...
90 		 */
91 		outb(0x80 + i, addr);
92 #endif
93 		sig[i] = inb(addr + i);
94 
95 		if (!i && (sig[0] & 0x80))
96 			return NULL;
97 	}
98 
99 	sig_str[0] = ((sig[0] >> 2) & 0x1f) + ('A' - 1);
100 	sig_str[1] = (((sig[0] & 3) << 3) | (sig[1] >> 5)) + ('A' - 1);
101 	sig_str[2] = (sig[1] & 0x1f) + ('A' - 1);
102 	rev = (sig[2] << 8) | sig[3];
103 	sprintf(sig_str + 3, "%04X", rev);
104 
105 	return sig_str;
106 }
107 
108 static int eisa_bus_match(struct device *dev, struct device_driver *drv)
109 {
110 	struct eisa_device *edev = to_eisa_device(dev);
111 	struct eisa_driver *edrv = to_eisa_driver(drv);
112 	const struct eisa_device_id *eids = edrv->id_table;
113 
114 	if (!eids)
115 		return 0;
116 
117 	while (strlen(eids->sig)) {
118 		if (!strcmp(eids->sig, edev->id.sig) &&
119 		    edev->state & EISA_CONFIG_ENABLED) {
120 			edev->id.driver_data = eids->driver_data;
121 			return 1;
122 		}
123 
124 		eids++;
125 	}
126 
127 	return 0;
128 }
129 
130 static int eisa_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
131 {
132 	struct eisa_device *edev = to_eisa_device(dev);
133 
134 	add_uevent_var(env, "MODALIAS=" EISA_DEVICE_MODALIAS_FMT, edev->id.sig);
135 	return 0;
136 }
137 
138 struct bus_type eisa_bus_type = {
139 	.name  = "eisa",
140 	.match = eisa_bus_match,
141 	.uevent = eisa_bus_uevent,
142 };
143 EXPORT_SYMBOL(eisa_bus_type);
144 
145 int eisa_driver_register(struct eisa_driver *edrv)
146 {
147 	edrv->driver.bus = &eisa_bus_type;
148 	return driver_register(&edrv->driver);
149 }
150 EXPORT_SYMBOL(eisa_driver_register);
151 
152 void eisa_driver_unregister(struct eisa_driver *edrv)
153 {
154 	driver_unregister(&edrv->driver);
155 }
156 EXPORT_SYMBOL(eisa_driver_unregister);
157 
158 static ssize_t eisa_show_sig(struct device *dev, struct device_attribute *attr,
159 			     char *buf)
160 {
161 	struct eisa_device *edev = to_eisa_device(dev);
162 	return sprintf(buf, "%s\n", edev->id.sig);
163 }
164 
165 static DEVICE_ATTR(signature, S_IRUGO, eisa_show_sig, NULL);
166 
167 static ssize_t eisa_show_state(struct device *dev,
168 			       struct device_attribute *attr,
169 			       char *buf)
170 {
171 	struct eisa_device *edev = to_eisa_device(dev);
172 	return sprintf(buf, "%d\n", edev->state & EISA_CONFIG_ENABLED);
173 }
174 
175 static DEVICE_ATTR(enabled, S_IRUGO, eisa_show_state, NULL);
176 
177 static ssize_t eisa_show_modalias(struct device *dev,
178 				  struct device_attribute *attr,
179 				  char *buf)
180 {
181 	struct eisa_device *edev = to_eisa_device(dev);
182 	return sprintf(buf, EISA_DEVICE_MODALIAS_FMT "\n", edev->id.sig);
183 }
184 
185 static DEVICE_ATTR(modalias, S_IRUGO, eisa_show_modalias, NULL);
186 
187 static int __init eisa_init_device(struct eisa_root_device *root,
188 				   struct eisa_device *edev,
189 				   int slot)
190 {
191 	char *sig;
192 	unsigned long sig_addr;
193 	int i;
194 
195 	sig_addr = SLOT_ADDRESS(root, slot) + EISA_VENDOR_ID_OFFSET;
196 
197 	sig = decode_eisa_sig(sig_addr);
198 	if (!sig)
199 		return -1;	/* No EISA device here */
200 
201 	memcpy(edev->id.sig, sig, EISA_SIG_LEN);
202 	edev->slot = slot;
203 	edev->state = inb(SLOT_ADDRESS(root, slot) + EISA_CONFIG_OFFSET)
204 		      & EISA_CONFIG_ENABLED;
205 	edev->base_addr = SLOT_ADDRESS(root, slot);
206 	edev->dma_mask = root->dma_mask; /* Default DMA mask */
207 	eisa_name_device(edev);
208 	edev->dev.parent = root->dev;
209 	edev->dev.bus = &eisa_bus_type;
210 	edev->dev.dma_mask = &edev->dma_mask;
211 	edev->dev.coherent_dma_mask = edev->dma_mask;
212 	dev_set_name(&edev->dev, "%02X:%02X", root->bus_nr, slot);
213 
214 	for (i = 0; i < EISA_MAX_RESOURCES; i++) {
215 #ifdef CONFIG_EISA_NAMES
216 		edev->res[i].name = edev->pretty_name;
217 #else
218 		edev->res[i].name = edev->id.sig;
219 #endif
220 	}
221 
222 	if (is_forced_dev(enable_dev, enable_dev_count, root, edev))
223 		edev->state = EISA_CONFIG_ENABLED | EISA_CONFIG_FORCED;
224 
225 	if (is_forced_dev(disable_dev, disable_dev_count, root, edev))
226 		edev->state = EISA_CONFIG_FORCED;
227 
228 	return 0;
229 }
230 
231 static int __init eisa_register_device(struct eisa_device *edev)
232 {
233 	int rc = device_register(&edev->dev);
234 	if (rc) {
235 		put_device(&edev->dev);
236 		return rc;
237 	}
238 
239 	rc = device_create_file(&edev->dev, &dev_attr_signature);
240 	if (rc)
241 		goto err_devreg;
242 	rc = device_create_file(&edev->dev, &dev_attr_enabled);
243 	if (rc)
244 		goto err_sig;
245 	rc = device_create_file(&edev->dev, &dev_attr_modalias);
246 	if (rc)
247 		goto err_enab;
248 
249 	return 0;
250 
251 err_enab:
252 	device_remove_file(&edev->dev, &dev_attr_enabled);
253 err_sig:
254 	device_remove_file(&edev->dev, &dev_attr_signature);
255 err_devreg:
256 	device_unregister(&edev->dev);
257 	return rc;
258 }
259 
260 static int __init eisa_request_resources(struct eisa_root_device *root,
261 					 struct eisa_device *edev,
262 					 int slot)
263 {
264 	int i;
265 
266 	for (i = 0; i < EISA_MAX_RESOURCES; i++) {
267 		/* Don't register resource for slot 0, since this is
268 		 * very likely to fail... :-( Instead, grab the EISA
269 		 * id, now we can display something in /proc/ioports.
270 		 */
271 
272 		/* Only one region for mainboard */
273 		if (!slot && i > 0) {
274 			edev->res[i].start = edev->res[i].end = 0;
275 			continue;
276 		}
277 
278 		if (slot) {
279 			edev->res[i].name  = NULL;
280 			edev->res[i].start = SLOT_ADDRESS(root, slot)
281 					     + (i * 0x400);
282 			edev->res[i].end   = edev->res[i].start + 0xff;
283 			edev->res[i].flags = IORESOURCE_IO;
284 		} else {
285 			edev->res[i].name  = NULL;
286 			edev->res[i].start = SLOT_ADDRESS(root, slot)
287 					     + EISA_VENDOR_ID_OFFSET;
288 			edev->res[i].end   = edev->res[i].start + 3;
289 			edev->res[i].flags = IORESOURCE_IO | IORESOURCE_BUSY;
290 		}
291 
292 		if (request_resource(root->res, &edev->res[i]))
293 			goto failed;
294 	}
295 
296 	return 0;
297 
298  failed:
299 	while (--i >= 0)
300 		release_resource(&edev->res[i]);
301 
302 	return -1;
303 }
304 
305 static void __init eisa_release_resources(struct eisa_device *edev)
306 {
307 	int i;
308 
309 	for (i = 0; i < EISA_MAX_RESOURCES; i++)
310 		if (edev->res[i].start || edev->res[i].end)
311 			release_resource(&edev->res[i]);
312 }
313 
314 static int __init eisa_probe(struct eisa_root_device *root)
315 {
316 	int i, c;
317 	struct eisa_device *edev;
318 	char *enabled_str;
319 
320 	dev_info(root->dev, "Probing EISA bus %d\n", root->bus_nr);
321 
322 	/* First try to get hold of slot 0. If there is no device
323 	 * here, simply fail, unless root->force_probe is set. */
324 
325 	edev = kzalloc(sizeof(*edev), GFP_KERNEL);
326 	if (!edev)
327 		return -ENOMEM;
328 
329 	if (eisa_request_resources(root, edev, 0)) {
330 		dev_warn(root->dev,
331 			 "EISA: Cannot allocate resource for mainboard\n");
332 		kfree(edev);
333 		if (!root->force_probe)
334 			return -EBUSY;
335 		goto force_probe;
336 	}
337 
338 	if (eisa_init_device(root, edev, 0)) {
339 		eisa_release_resources(edev);
340 		kfree(edev);
341 		if (!root->force_probe)
342 			return -ENODEV;
343 		goto force_probe;
344 	}
345 
346 	dev_info(&edev->dev, "EISA: Mainboard %s detected\n", edev->id.sig);
347 
348 	if (eisa_register_device(edev)) {
349 		dev_err(&edev->dev, "EISA: Failed to register %s\n",
350 			edev->id.sig);
351 		eisa_release_resources(edev);
352 		kfree(edev);
353 	}
354 
355  force_probe:
356 
357 	for (c = 0, i = 1; i <= root->slots; i++) {
358 		edev = kzalloc(sizeof(*edev), GFP_KERNEL);
359 		if (!edev) {
360 			dev_err(root->dev, "EISA: Out of memory for slot %d\n",
361 				i);
362 			continue;
363 		}
364 
365 		if (eisa_request_resources(root, edev, i)) {
366 			dev_warn(root->dev,
367 				 "Cannot allocate resource for EISA slot %d\n",
368 				 i);
369 			kfree(edev);
370 			continue;
371 		}
372 
373 		if (eisa_init_device(root, edev, i)) {
374 			eisa_release_resources(edev);
375 			kfree(edev);
376 			continue;
377 		}
378 
379 		if (edev->state == (EISA_CONFIG_ENABLED | EISA_CONFIG_FORCED))
380 			enabled_str = " (forced enabled)";
381 		else if (edev->state == EISA_CONFIG_FORCED)
382 			enabled_str = " (forced disabled)";
383 		else if (edev->state == 0)
384 			enabled_str = " (disabled)";
385 		else
386 			enabled_str = "";
387 
388 		dev_info(&edev->dev, "EISA: slot %d: %s detected%s\n", i,
389 			 edev->id.sig, enabled_str);
390 
391 		c++;
392 
393 		if (eisa_register_device(edev)) {
394 			dev_err(&edev->dev, "EISA: Failed to register %s\n",
395 				edev->id.sig);
396 			eisa_release_resources(edev);
397 			kfree(edev);
398 		}
399 	}
400 
401 	dev_info(root->dev, "EISA: Detected %d card%s\n", c, c == 1 ? "" : "s");
402 	return 0;
403 }
404 
405 static struct resource eisa_root_res = {
406 	.name  = "EISA root resource",
407 	.start = 0,
408 	.end   = 0xffffffff,
409 	.flags = IORESOURCE_IO,
410 };
411 
412 static int eisa_bus_count;
413 
414 int __init eisa_root_register(struct eisa_root_device *root)
415 {
416 	int err;
417 
418 	/* Use our own resources to check if this bus base address has
419 	 * been already registered. This prevents the virtual root
420 	 * device from registering after the real one has, for
421 	 * example... */
422 
423 	root->eisa_root_res.name  = eisa_root_res.name;
424 	root->eisa_root_res.start = root->res->start;
425 	root->eisa_root_res.end   = root->res->end;
426 	root->eisa_root_res.flags = IORESOURCE_BUSY;
427 
428 	err = request_resource(&eisa_root_res, &root->eisa_root_res);
429 	if (err)
430 		return err;
431 
432 	root->bus_nr = eisa_bus_count++;
433 
434 	err = eisa_probe(root);
435 	if (err)
436 		release_resource(&root->eisa_root_res);
437 
438 	return err;
439 }
440 
441 static int __init eisa_init(void)
442 {
443 	int r;
444 
445 	r = bus_register(&eisa_bus_type);
446 	if (r)
447 		return r;
448 
449 	printk(KERN_INFO "EISA bus registered\n");
450 	return 0;
451 }
452 
453 module_param_array(enable_dev, int, &enable_dev_count, 0444);
454 module_param_array(disable_dev, int, &disable_dev_count, 0444);
455 
456 postcore_initcall(eisa_init);
457 
458 int EISA_bus;		/* for legacy drivers */
459 EXPORT_SYMBOL(EISA_bus);
460