xref: /openbmc/linux/drivers/eisa/eisa-bus.c (revision 349f631d)
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 signature_show(struct device *dev,
159 			      struct device_attribute *attr, char *buf)
160 {
161 	struct eisa_device *edev = to_eisa_device(dev);
162 	return sprintf(buf, "%s\n", edev->id.sig);
163 }
164 static DEVICE_ATTR_RO(signature);
165 
166 static ssize_t enabled_show(struct device *dev,
167 			    struct device_attribute *attr, char *buf)
168 {
169 	struct eisa_device *edev = to_eisa_device(dev);
170 	return sprintf(buf, "%d\n", edev->state & EISA_CONFIG_ENABLED);
171 }
172 static DEVICE_ATTR_RO(enabled);
173 
174 static ssize_t modalias_show(struct device *dev,
175 			     struct device_attribute *attr, char *buf)
176 {
177 	struct eisa_device *edev = to_eisa_device(dev);
178 	return sprintf(buf, EISA_DEVICE_MODALIAS_FMT "\n", edev->id.sig);
179 }
180 static DEVICE_ATTR_RO(modalias);
181 
182 static int __init eisa_init_device(struct eisa_root_device *root,
183 				   struct eisa_device *edev,
184 				   int slot)
185 {
186 	char *sig;
187 	unsigned long sig_addr;
188 	int i;
189 
190 	sig_addr = SLOT_ADDRESS(root, slot) + EISA_VENDOR_ID_OFFSET;
191 
192 	sig = decode_eisa_sig(sig_addr);
193 	if (!sig)
194 		return -1;	/* No EISA device here */
195 
196 	memcpy(edev->id.sig, sig, EISA_SIG_LEN);
197 	edev->slot = slot;
198 	edev->state = inb(SLOT_ADDRESS(root, slot) + EISA_CONFIG_OFFSET)
199 		      & EISA_CONFIG_ENABLED;
200 	edev->base_addr = SLOT_ADDRESS(root, slot);
201 	edev->dma_mask = root->dma_mask; /* Default DMA mask */
202 	eisa_name_device(edev);
203 	edev->dev.parent = root->dev;
204 	edev->dev.bus = &eisa_bus_type;
205 	edev->dev.dma_mask = &edev->dma_mask;
206 	edev->dev.coherent_dma_mask = edev->dma_mask;
207 	dev_set_name(&edev->dev, "%02X:%02X", root->bus_nr, slot);
208 
209 	for (i = 0; i < EISA_MAX_RESOURCES; i++) {
210 #ifdef CONFIG_EISA_NAMES
211 		edev->res[i].name = edev->pretty_name;
212 #else
213 		edev->res[i].name = edev->id.sig;
214 #endif
215 	}
216 
217 	if (is_forced_dev(enable_dev, enable_dev_count, root, edev))
218 		edev->state = EISA_CONFIG_ENABLED | EISA_CONFIG_FORCED;
219 
220 	if (is_forced_dev(disable_dev, disable_dev_count, root, edev))
221 		edev->state = EISA_CONFIG_FORCED;
222 
223 	return 0;
224 }
225 
226 static int __init eisa_register_device(struct eisa_device *edev)
227 {
228 	int rc = device_register(&edev->dev);
229 	if (rc) {
230 		put_device(&edev->dev);
231 		return rc;
232 	}
233 
234 	rc = device_create_file(&edev->dev, &dev_attr_signature);
235 	if (rc)
236 		goto err_devreg;
237 	rc = device_create_file(&edev->dev, &dev_attr_enabled);
238 	if (rc)
239 		goto err_sig;
240 	rc = device_create_file(&edev->dev, &dev_attr_modalias);
241 	if (rc)
242 		goto err_enab;
243 
244 	return 0;
245 
246 err_enab:
247 	device_remove_file(&edev->dev, &dev_attr_enabled);
248 err_sig:
249 	device_remove_file(&edev->dev, &dev_attr_signature);
250 err_devreg:
251 	device_unregister(&edev->dev);
252 	return rc;
253 }
254 
255 static int __init eisa_request_resources(struct eisa_root_device *root,
256 					 struct eisa_device *edev,
257 					 int slot)
258 {
259 	int i;
260 
261 	for (i = 0; i < EISA_MAX_RESOURCES; i++) {
262 		/* Don't register resource for slot 0, since this is
263 		 * very likely to fail... :-( Instead, grab the EISA
264 		 * id, now we can display something in /proc/ioports.
265 		 */
266 
267 		/* Only one region for mainboard */
268 		if (!slot && i > 0) {
269 			edev->res[i].start = edev->res[i].end = 0;
270 			continue;
271 		}
272 
273 		if (slot) {
274 			edev->res[i].name  = NULL;
275 			edev->res[i].start = SLOT_ADDRESS(root, slot)
276 					     + (i * 0x400);
277 			edev->res[i].end   = edev->res[i].start + 0xff;
278 			edev->res[i].flags = IORESOURCE_IO;
279 		} else {
280 			edev->res[i].name  = NULL;
281 			edev->res[i].start = SLOT_ADDRESS(root, slot)
282 					     + EISA_VENDOR_ID_OFFSET;
283 			edev->res[i].end   = edev->res[i].start + 3;
284 			edev->res[i].flags = IORESOURCE_IO | IORESOURCE_BUSY;
285 		}
286 
287 		if (request_resource(root->res, &edev->res[i]))
288 			goto failed;
289 	}
290 
291 	return 0;
292 
293  failed:
294 	while (--i >= 0)
295 		release_resource(&edev->res[i]);
296 
297 	return -1;
298 }
299 
300 static void __init eisa_release_resources(struct eisa_device *edev)
301 {
302 	int i;
303 
304 	for (i = 0; i < EISA_MAX_RESOURCES; i++)
305 		if (edev->res[i].start || edev->res[i].end)
306 			release_resource(&edev->res[i]);
307 }
308 
309 static int __init eisa_probe(struct eisa_root_device *root)
310 {
311 	int i, c;
312 	struct eisa_device *edev;
313 	char *enabled_str;
314 
315 	dev_info(root->dev, "Probing EISA bus %d\n", root->bus_nr);
316 
317 	/* First try to get hold of slot 0. If there is no device
318 	 * here, simply fail, unless root->force_probe is set. */
319 
320 	edev = kzalloc(sizeof(*edev), GFP_KERNEL);
321 	if (!edev)
322 		return -ENOMEM;
323 
324 	if (eisa_request_resources(root, edev, 0)) {
325 		dev_warn(root->dev,
326 			 "EISA: Cannot allocate resource for mainboard\n");
327 		kfree(edev);
328 		if (!root->force_probe)
329 			return -EBUSY;
330 		goto force_probe;
331 	}
332 
333 	if (eisa_init_device(root, edev, 0)) {
334 		eisa_release_resources(edev);
335 		kfree(edev);
336 		if (!root->force_probe)
337 			return -ENODEV;
338 		goto force_probe;
339 	}
340 
341 	dev_info(&edev->dev, "EISA: Mainboard %s detected\n", edev->id.sig);
342 
343 	if (eisa_register_device(edev)) {
344 		dev_err(&edev->dev, "EISA: Failed to register %s\n",
345 			edev->id.sig);
346 		eisa_release_resources(edev);
347 		kfree(edev);
348 	}
349 
350  force_probe:
351 
352 	for (c = 0, i = 1; i <= root->slots; i++) {
353 		edev = kzalloc(sizeof(*edev), GFP_KERNEL);
354 		if (!edev) {
355 			dev_err(root->dev, "EISA: Out of memory for slot %d\n",
356 				i);
357 			continue;
358 		}
359 
360 		if (eisa_request_resources(root, edev, i)) {
361 			dev_warn(root->dev,
362 				 "Cannot allocate resource for EISA slot %d\n",
363 				 i);
364 			kfree(edev);
365 			continue;
366 		}
367 
368 		if (eisa_init_device(root, edev, i)) {
369 			eisa_release_resources(edev);
370 			kfree(edev);
371 			continue;
372 		}
373 
374 		if (edev->state == (EISA_CONFIG_ENABLED | EISA_CONFIG_FORCED))
375 			enabled_str = " (forced enabled)";
376 		else if (edev->state == EISA_CONFIG_FORCED)
377 			enabled_str = " (forced disabled)";
378 		else if (edev->state == 0)
379 			enabled_str = " (disabled)";
380 		else
381 			enabled_str = "";
382 
383 		dev_info(&edev->dev, "EISA: slot %d: %s detected%s\n", i,
384 			 edev->id.sig, enabled_str);
385 
386 		c++;
387 
388 		if (eisa_register_device(edev)) {
389 			dev_err(&edev->dev, "EISA: Failed to register %s\n",
390 				edev->id.sig);
391 			eisa_release_resources(edev);
392 			kfree(edev);
393 		}
394 	}
395 
396 	dev_info(root->dev, "EISA: Detected %d card%s\n", c, c == 1 ? "" : "s");
397 	return 0;
398 }
399 
400 static struct resource eisa_root_res = {
401 	.name  = "EISA root resource",
402 	.start = 0,
403 	.end   = 0xffffffff,
404 	.flags = IORESOURCE_IO,
405 };
406 
407 static int eisa_bus_count;
408 
409 int __init eisa_root_register(struct eisa_root_device *root)
410 {
411 	int err;
412 
413 	/* Use our own resources to check if this bus base address has
414 	 * been already registered. This prevents the virtual root
415 	 * device from registering after the real one has, for
416 	 * example... */
417 
418 	root->eisa_root_res.name  = eisa_root_res.name;
419 	root->eisa_root_res.start = root->res->start;
420 	root->eisa_root_res.end   = root->res->end;
421 	root->eisa_root_res.flags = IORESOURCE_BUSY;
422 
423 	err = request_resource(&eisa_root_res, &root->eisa_root_res);
424 	if (err)
425 		return err;
426 
427 	root->bus_nr = eisa_bus_count++;
428 
429 	err = eisa_probe(root);
430 	if (err)
431 		release_resource(&root->eisa_root_res);
432 
433 	return err;
434 }
435 
436 static int __init eisa_init(void)
437 {
438 	int r;
439 
440 	r = bus_register(&eisa_bus_type);
441 	if (r)
442 		return r;
443 
444 	printk(KERN_INFO "EISA bus registered\n");
445 	return 0;
446 }
447 
448 module_param_array(enable_dev, int, &enable_dev_count, 0444);
449 module_param_array(disable_dev, int, &disable_dev_count, 0444);
450 
451 postcore_initcall(eisa_init);
452 
453 int EISA_bus;		/* for legacy drivers */
454 EXPORT_SYMBOL(EISA_bus);
455