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
22struct eisa_device_info {
23	struct eisa_device_id id;
24	char name[50];
25};
26
27#ifdef CONFIG_EISA_NAMES
28static 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
36static int enable_dev[EISA_MAX_FORCED_DEV];
37static unsigned int enable_dev_count;
38static int disable_dev[EISA_MAX_FORCED_DEV];
39static unsigned int disable_dev_count;
40
41static 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
57static 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
75static 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
108static 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
130static 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
138struct bus_type eisa_bus_type = {
139	.name  = "eisa",
140	.match = eisa_bus_match,
141	.uevent = eisa_bus_uevent,
142};
143EXPORT_SYMBOL(eisa_bus_type);
144
145int eisa_driver_register(struct eisa_driver *edrv)
146{
147	edrv->driver.bus = &eisa_bus_type;
148	return driver_register(&edrv->driver);
149}
150EXPORT_SYMBOL(eisa_driver_register);
151
152void eisa_driver_unregister(struct eisa_driver *edrv)
153{
154	driver_unregister(&edrv->driver);
155}
156EXPORT_SYMBOL(eisa_driver_unregister);
157
158static 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
165static DEVICE_ATTR(signature, S_IRUGO, eisa_show_sig, NULL);
166
167static 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
175static DEVICE_ATTR(enabled, S_IRUGO, eisa_show_state, NULL);
176
177static 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
185static DEVICE_ATTR(modalias, S_IRUGO, eisa_show_modalias, NULL);
186
187static 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
231static 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
251err_enab:
252	device_remove_file(&edev->dev, &dev_attr_enabled);
253err_sig:
254	device_remove_file(&edev->dev, &dev_attr_signature);
255err_devreg:
256	device_unregister(&edev->dev);
257	return rc;
258}
259
260static 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
305static 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
314static 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
405static struct resource eisa_root_res = {
406	.name  = "EISA root resource",
407	.start = 0,
408	.end   = 0xffffffff,
409	.flags = IORESOURCE_IO,
410};
411
412static int eisa_bus_count;
413
414int __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
441static 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
453module_param_array(enable_dev, int, &enable_dev_count, 0444);
454module_param_array(disable_dev, int, &disable_dev_count, 0444);
455
456postcore_initcall(eisa_init);
457
458int EISA_bus;		/* for legacy drivers */
459EXPORT_SYMBOL(EISA_bus);
460