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			strscpy(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(const struct device *dev, struct kobj_uevent_env *env)
131{
132	const 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 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}
164static DEVICE_ATTR_RO(signature);
165
166static 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}
172static DEVICE_ATTR_RO(enabled);
173
174static 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}
180static DEVICE_ATTR_RO(modalias);
181
182static 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
226static 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
246err_enab:
247	device_remove_file(&edev->dev, &dev_attr_enabled);
248err_sig:
249	device_remove_file(&edev->dev, &dev_attr_signature);
250err_devreg:
251	device_unregister(&edev->dev);
252	return rc;
253}
254
255static 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
300static 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
309static 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
400static struct resource eisa_root_res = {
401	.name  = "EISA root resource",
402	.start = 0,
403	.end   = 0xffffffff,
404	.flags = IORESOURCE_IO,
405};
406
407static int eisa_bus_count;
408
409int __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
436static 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
448module_param_array(enable_dev, int, &enable_dev_count, 0444);
449module_param_array(disable_dev, int, &disable_dev_count, 0444);
450
451postcore_initcall(eisa_init);
452
453int EISA_bus;		/* for legacy drivers */
454EXPORT_SYMBOL(EISA_bus);
455