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1/*
2 * ACPI PCI Hot Plug IBM Extension
3 *
4 * Copyright (C) 2004 Vernon Mauery <vernux@us.ibm.com>
5 * Copyright (C) 2004 IBM Corp.
6 *
7 * All rights reserved.
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or (at
12 * your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
17 * NON INFRINGEMENT. See the GNU General Public License for more
18 * details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 *
24 * Send feedback to <vernux@us.ibm.com>
25 *
26 */
27
28#include <linux/init.h>
29#include <linux/slab.h>
30#include <linux/module.h>
31#include <linux/kernel.h>
32#include <acpi/acpi_bus.h>
33#include <linux/sysfs.h>
34#include <linux/kobject.h>
35#include <asm/uaccess.h>
36#include <linux/moduleparam.h>
37#include <linux/pci.h>
38
39#include "acpiphp.h"
40#include "../pci.h"
41
42#define DRIVER_VERSION "1.0.1"
43#define DRIVER_AUTHOR "Irene Zubarev <zubarev@us.ibm.com>, Vernon Mauery <vernux@us.ibm.com>"
44#define DRIVER_DESC "ACPI Hot Plug PCI Controller Driver IBM extension"
45
46static bool debug;
47
48MODULE_AUTHOR(DRIVER_AUTHOR);
49MODULE_DESCRIPTION(DRIVER_DESC);
50MODULE_LICENSE("GPL");
51MODULE_VERSION(DRIVER_VERSION);
52module_param(debug, bool, 0644);
53MODULE_PARM_DESC(debug, " Debugging mode enabled or not");
54#define MY_NAME "acpiphp_ibm"
55
56#undef dbg
57#define dbg(format, arg...) \
58do { \
59 if (debug) \
60 printk(KERN_DEBUG "%s: " format, \
61 MY_NAME , ## arg); \
62} while (0)
63
64#define FOUND_APCI 0x61504349
65/* these are the names for the IBM ACPI pseudo-device */
66#define IBM_HARDWARE_ID1 "IBM37D0"
67#define IBM_HARDWARE_ID2 "IBM37D4"
68
69#define hpslot_to_sun(A) (((struct slot *)((A)->private))->acpi_slot->sun)
70
71/* union apci_descriptor - allows access to the
72 * various device descriptors that are embedded in the
73 * aPCI table
74 */
75union apci_descriptor {
76 struct {
77 char sig[4];
78 u8 len;
79 } header;
80 struct {
81 u8 type;
82 u8 len;
83 u16 slot_id;
84 u8 bus_id;
85 u8 dev_num;
86 u8 slot_num;
87 u8 slot_attr[2];
88 u8 attn;
89 u8 status[2];
90 u8 sun;
91 u8 res[3];
92 } slot;
93 struct {
94 u8 type;
95 u8 len;
96 } generic;
97};
98
99/* struct notification - keeps info about the device
100 * that cause the ACPI notification event
101 */
102struct notification {
103 struct acpi_device *device;
104 u8 event;
105};
106
107static int ibm_set_attention_status(struct hotplug_slot *slot, u8 status);
108static int ibm_get_attention_status(struct hotplug_slot *slot, u8 *status);
109static void ibm_handle_events(acpi_handle handle, u32 event, void *context);
110static int ibm_get_table_from_acpi(char **bufp);
111static ssize_t ibm_read_apci_table(struct file *filp, struct kobject *kobj,
112 struct bin_attribute *bin_attr,
113 char *buffer, loff_t pos, size_t size);
114static acpi_status __init ibm_find_acpi_device(acpi_handle handle,
115 u32 lvl, void *context, void **rv);
116static int __init ibm_acpiphp_init(void);
117static void __exit ibm_acpiphp_exit(void);
118
119static acpi_handle ibm_acpi_handle;
120static struct notification ibm_note;
121static struct bin_attribute ibm_apci_table_attr = {
122 .attr = {
123 .name = "apci_table",
124 .mode = S_IRUGO,
125 },
126 .read = ibm_read_apci_table,
127 .write = NULL,
128};
129static struct acpiphp_attention_info ibm_attention_info =
130{
131 .set_attn = ibm_set_attention_status,
132 .get_attn = ibm_get_attention_status,
133 .owner = THIS_MODULE,
134};
135
136/**
137 * ibm_slot_from_id - workaround for bad ibm hardware
138 * @id: the slot number that linux refers to the slot by
139 *
140 * Description: This method returns the aCPI slot descriptor
141 * corresponding to the Linux slot number. This descriptor
142 * has info about the aPCI slot id and attention status.
143 * This descriptor must be freed using kfree when done.
144 */
145static union apci_descriptor *ibm_slot_from_id(int id)
146{
147 int ind = 0, size;
148 union apci_descriptor *ret = NULL, *des;
149 char *table;
150
151 size = ibm_get_table_from_acpi(&table);
152 des = (union apci_descriptor *)table;
153 if (memcmp(des->header.sig, "aPCI", 4) != 0)
154 goto ibm_slot_done;
155
156 des = (union apci_descriptor *)&table[ind += des->header.len];
157 while (ind < size && (des->generic.type != 0x82 ||
158 des->slot.slot_num != id)) {
159 des = (union apci_descriptor *)&table[ind += des->generic.len];
160 }
161
162 if (ind < size && des->slot.slot_num == id)
163 ret = des;
164
165ibm_slot_done:
166 if (ret) {
167 ret = kmalloc(sizeof(union apci_descriptor), GFP_KERNEL);
168 memcpy(ret, des, sizeof(union apci_descriptor));
169 }
170 kfree(table);
171 return ret;
172}
173
174/**
175 * ibm_set_attention_status - callback method to set the attention LED
176 * @slot: the hotplug_slot to work with
177 * @status: what to set the LED to (0 or 1)
178 *
179 * Description: This method is registered with the acpiphp module as a
180 * callback to do the device specific task of setting the LED status.
181 */
182static int ibm_set_attention_status(struct hotplug_slot *slot, u8 status)
183{
184 union acpi_object args[2];
185 struct acpi_object_list params = { .pointer = args, .count = 2 };
186 acpi_status stat;
187 unsigned long long rc;
188 union apci_descriptor *ibm_slot;
189
190 ibm_slot = ibm_slot_from_id(hpslot_to_sun(slot));
191
192 dbg("%s: set slot %d (%d) attention status to %d\n", __func__,
193 ibm_slot->slot.slot_num, ibm_slot->slot.slot_id,
194 (status ? 1 : 0));
195
196 args[0].type = ACPI_TYPE_INTEGER;
197 args[0].integer.value = ibm_slot->slot.slot_id;
198 args[1].type = ACPI_TYPE_INTEGER;
199 args[1].integer.value = (status) ? 1 : 0;
200
201 kfree(ibm_slot);
202
203 stat = acpi_evaluate_integer(ibm_acpi_handle, "APLS", ¶ms, &rc);
204 if (ACPI_FAILURE(stat)) {
205 err("APLS evaluation failed: 0x%08x\n", stat);
206 return -ENODEV;
207 } else if (!rc) {
208 err("APLS method failed: 0x%08llx\n", rc);
209 return -ERANGE;
210 }
211 return 0;
212}
213
214/**
215 * ibm_get_attention_status - callback method to get attention LED status
216 * @slot: the hotplug_slot to work with
217 * @status: returns what the LED is set to (0 or 1)
218 *
219 * Description: This method is registered with the acpiphp module as a
220 * callback to do the device specific task of getting the LED status.
221 *
222 * Because there is no direct method of getting the LED status directly
223 * from an ACPI call, we read the aPCI table and parse out our
224 * slot descriptor to read the status from that.
225 */
226static int ibm_get_attention_status(struct hotplug_slot *slot, u8 *status)
227{
228 union apci_descriptor *ibm_slot;
229
230 ibm_slot = ibm_slot_from_id(hpslot_to_sun(slot));
231
232 if (ibm_slot->slot.attn & 0xa0 || ibm_slot->slot.status[1] & 0x08)
233 *status = 1;
234 else
235 *status = 0;
236
237 dbg("%s: get slot %d (%d) attention status is %d\n", __func__,
238 ibm_slot->slot.slot_num, ibm_slot->slot.slot_id,
239 *status);
240
241 kfree(ibm_slot);
242 return 0;
243}
244
245/**
246 * ibm_handle_events - listens for ACPI events for the IBM37D0 device
247 * @handle: an ACPI handle to the device that caused the event
248 * @event: the event info (device specific)
249 * @context: passed context (our notification struct)
250 *
251 * Description: This method is registered as a callback with the ACPI
252 * subsystem it is called when this device has an event to notify the OS of.
253 *
254 * The events actually come from the device as two events that get
255 * synthesized into one event with data by this function. The event
256 * ID comes first and then the slot number that caused it. We report
257 * this as one event to the OS.
258 *
259 * From section 5.6.2.2 of the ACPI 2.0 spec, I understand that the OSPM will
260 * only re-enable the interrupt that causes this event AFTER this method
261 * has returned, thereby enforcing serial access for the notification struct.
262 */
263static void ibm_handle_events(acpi_handle handle, u32 event, void *context)
264{
265 u8 detail = event & 0x0f;
266 u8 subevent = event & 0xf0;
267 struct notification *note = context;
268
269 dbg("%s: Received notification %02x\n", __func__, event);
270
271 if (subevent == 0x80) {
272 dbg("%s: generationg bus event\n", __func__);
273 acpi_bus_generate_proc_event(note->device, note->event, detail);
274 acpi_bus_generate_netlink_event(note->device->pnp.device_class,
275 dev_name(¬e->device->dev),
276 note->event, detail);
277 } else
278 note->event = event;
279}
280
281/**
282 * ibm_get_table_from_acpi - reads the APLS buffer from ACPI
283 * @bufp: address to pointer to allocate for the table
284 *
285 * Description: This method reads the APLS buffer in from ACPI and
286 * stores the "stripped" table into a single buffer
287 * it allocates and passes the address back in bufp.
288 *
289 * If NULL is passed in as buffer, this method only calculates
290 * the size of the table and returns that without filling
291 * in the buffer.
292 *
293 * Returns < 0 on error or the size of the table on success.
294 */
295static int ibm_get_table_from_acpi(char **bufp)
296{
297 union acpi_object *package;
298 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
299 acpi_status status;
300 char *lbuf = NULL;
301 int i, size = -EIO;
302
303 status = acpi_evaluate_object(ibm_acpi_handle, "APCI", NULL, &buffer);
304 if (ACPI_FAILURE(status)) {
305 err("%s: APCI evaluation failed\n", __func__);
306 return -ENODEV;
307 }
308
309 package = (union acpi_object *) buffer.pointer;
310 if (!(package) ||
311 (package->type != ACPI_TYPE_PACKAGE) ||
312 !(package->package.elements)) {
313 err("%s: Invalid APCI object\n", __func__);
314 goto read_table_done;
315 }
316
317 for(size = 0, i = 0; i < package->package.count; i++) {
318 if (package->package.elements[i].type != ACPI_TYPE_BUFFER) {
319 err("%s: Invalid APCI element %d\n", __func__, i);
320 goto read_table_done;
321 }
322 size += package->package.elements[i].buffer.length;
323 }
324
325 if (bufp == NULL)
326 goto read_table_done;
327
328 lbuf = kzalloc(size, GFP_KERNEL);
329 dbg("%s: element count: %i, ASL table size: %i, &table = 0x%p\n",
330 __func__, package->package.count, size, lbuf);
331
332 if (lbuf) {
333 *bufp = lbuf;
334 } else {
335 size = -ENOMEM;
336 goto read_table_done;
337 }
338
339 size = 0;
340 for (i=0; i<package->package.count; i++) {
341 memcpy(&lbuf[size],
342 package->package.elements[i].buffer.pointer,
343 package->package.elements[i].buffer.length);
344 size += package->package.elements[i].buffer.length;
345 }
346
347read_table_done:
348 kfree(buffer.pointer);
349 return size;
350}
351
352/**
353 * ibm_read_apci_table - callback for the sysfs apci_table file
354 * @filp: the open sysfs file
355 * @kobj: the kobject this binary attribute is a part of
356 * @bin_attr: struct bin_attribute for this file
357 * @buffer: the kernel space buffer to fill
358 * @pos: the offset into the file
359 * @size: the number of bytes requested
360 *
361 * Description: Gets registered with sysfs as the reader callback
362 * to be executed when /sys/bus/pci/slots/apci_table gets read.
363 *
364 * Since we don't get notified on open and close for this file,
365 * things get really tricky here...
366 * our solution is to only allow reading the table in all at once.
367 */
368static ssize_t ibm_read_apci_table(struct file *filp, struct kobject *kobj,
369 struct bin_attribute *bin_attr,
370 char *buffer, loff_t pos, size_t size)
371{
372 int bytes_read = -EINVAL;
373 char *table = NULL;
374
375 dbg("%s: pos = %d, size = %zd\n", __func__, (int)pos, size);
376
377 if (pos == 0) {
378 bytes_read = ibm_get_table_from_acpi(&table);
379 if (bytes_read > 0 && bytes_read <= size)
380 memcpy(buffer, table, bytes_read);
381 kfree(table);
382 }
383 return bytes_read;
384}
385
386/**
387 * ibm_find_acpi_device - callback to find our ACPI device
388 * @handle: the ACPI handle of the device we are inspecting
389 * @lvl: depth into the namespace tree
390 * @context: a pointer to our handle to fill when we find the device
391 * @rv: a return value to fill if desired
392 *
393 * Description: Used as a callback when calling acpi_walk_namespace
394 * to find our device. When this method returns non-zero
395 * acpi_walk_namespace quits its search and returns our value.
396 */
397static acpi_status __init ibm_find_acpi_device(acpi_handle handle,
398 u32 lvl, void *context, void **rv)
399{
400 acpi_handle *phandle = (acpi_handle *)context;
401 acpi_status status;
402 struct acpi_device_info *info;
403 int retval = 0;
404
405 status = acpi_get_object_info(handle, &info);
406 if (ACPI_FAILURE(status)) {
407 err("%s: Failed to get device information status=0x%x\n",
408 __func__, status);
409 return retval;
410 }
411
412 if (info->current_status && (info->valid & ACPI_VALID_HID) &&
413 (!strcmp(info->hardware_id.string, IBM_HARDWARE_ID1) ||
414 !strcmp(info->hardware_id.string, IBM_HARDWARE_ID2))) {
415 dbg("found hardware: %s, handle: %p\n",
416 info->hardware_id.string, handle);
417 *phandle = handle;
418 /* returning non-zero causes the search to stop
419 * and returns this value to the caller of
420 * acpi_walk_namespace, but it also causes some warnings
421 * in the acpi debug code to print...
422 */
423 retval = FOUND_APCI;
424 }
425 kfree(info);
426 return retval;
427}
428
429static int __init ibm_acpiphp_init(void)
430{
431 int retval = 0;
432 acpi_status status;
433 struct acpi_device *device;
434 struct kobject *sysdir = &pci_slots_kset->kobj;
435
436 dbg("%s\n", __func__);
437
438 if (acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
439 ACPI_UINT32_MAX, ibm_find_acpi_device, NULL,
440 &ibm_acpi_handle, NULL) != FOUND_APCI) {
441 err("%s: acpi_walk_namespace failed\n", __func__);
442 retval = -ENODEV;
443 goto init_return;
444 }
445 dbg("%s: found IBM aPCI device\n", __func__);
446 if (acpi_bus_get_device(ibm_acpi_handle, &device)) {
447 err("%s: acpi_bus_get_device failed\n", __func__);
448 retval = -ENODEV;
449 goto init_return;
450 }
451 if (acpiphp_register_attention(&ibm_attention_info)) {
452 retval = -ENODEV;
453 goto init_return;
454 }
455
456 ibm_note.device = device;
457 status = acpi_install_notify_handler(ibm_acpi_handle,
458 ACPI_DEVICE_NOTIFY, ibm_handle_events,
459 &ibm_note);
460 if (ACPI_FAILURE(status)) {
461 err("%s: Failed to register notification handler\n",
462 __func__);
463 retval = -EBUSY;
464 goto init_cleanup;
465 }
466
467 ibm_apci_table_attr.size = ibm_get_table_from_acpi(NULL);
468 retval = sysfs_create_bin_file(sysdir, &ibm_apci_table_attr);
469
470 return retval;
471
472init_cleanup:
473 acpiphp_unregister_attention(&ibm_attention_info);
474init_return:
475 return retval;
476}
477
478static void __exit ibm_acpiphp_exit(void)
479{
480 acpi_status status;
481 struct kobject *sysdir = &pci_slots_kset->kobj;
482
483 dbg("%s\n", __func__);
484
485 if (acpiphp_unregister_attention(&ibm_attention_info))
486 err("%s: attention info deregistration failed", __func__);
487
488 status = acpi_remove_notify_handler(
489 ibm_acpi_handle,
490 ACPI_DEVICE_NOTIFY,
491 ibm_handle_events);
492 if (ACPI_FAILURE(status))
493 err("%s: Notification handler removal failed\n", __func__);
494 /* remove the /sys entries */
495 sysfs_remove_bin_file(sysdir, &ibm_apci_table_attr);
496}
497
498module_init(ibm_acpiphp_init);
499module_exit(ibm_acpiphp_exit);
1/*
2 * ACPI PCI Hot Plug IBM Extension
3 *
4 * Copyright (C) 2004 Vernon Mauery <vernux@us.ibm.com>
5 * Copyright (C) 2004 IBM Corp.
6 *
7 * All rights reserved.
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or (at
12 * your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
17 * NON INFRINGEMENT. See the GNU General Public License for more
18 * details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 *
24 * Send feedback to <vernux@us.ibm.com>
25 *
26 */
27
28#define pr_fmt(fmt) "acpiphp_ibm: " fmt
29
30#include <linux/init.h>
31#include <linux/slab.h>
32#include <linux/module.h>
33#include <linux/kernel.h>
34#include <linux/sysfs.h>
35#include <linux/kobject.h>
36#include <linux/moduleparam.h>
37#include <linux/pci.h>
38#include <asm/uaccess.h>
39
40#include "acpiphp.h"
41#include "../pci.h"
42
43#define DRIVER_VERSION "1.0.1"
44#define DRIVER_AUTHOR "Irene Zubarev <zubarev@us.ibm.com>, Vernon Mauery <vernux@us.ibm.com>"
45#define DRIVER_DESC "ACPI Hot Plug PCI Controller Driver IBM extension"
46
47
48MODULE_AUTHOR(DRIVER_AUTHOR);
49MODULE_DESCRIPTION(DRIVER_DESC);
50MODULE_LICENSE("GPL");
51MODULE_VERSION(DRIVER_VERSION);
52
53#define FOUND_APCI 0x61504349
54/* these are the names for the IBM ACPI pseudo-device */
55#define IBM_HARDWARE_ID1 "IBM37D0"
56#define IBM_HARDWARE_ID2 "IBM37D4"
57
58#define hpslot_to_sun(A) (((struct slot *)((A)->private))->sun)
59
60/* union apci_descriptor - allows access to the
61 * various device descriptors that are embedded in the
62 * aPCI table
63 */
64union apci_descriptor {
65 struct {
66 char sig[4];
67 u8 len;
68 } header;
69 struct {
70 u8 type;
71 u8 len;
72 u16 slot_id;
73 u8 bus_id;
74 u8 dev_num;
75 u8 slot_num;
76 u8 slot_attr[2];
77 u8 attn;
78 u8 status[2];
79 u8 sun;
80 u8 res[3];
81 } slot;
82 struct {
83 u8 type;
84 u8 len;
85 } generic;
86};
87
88/* struct notification - keeps info about the device
89 * that cause the ACPI notification event
90 */
91struct notification {
92 struct acpi_device *device;
93 u8 event;
94};
95
96static int ibm_set_attention_status(struct hotplug_slot *slot, u8 status);
97static int ibm_get_attention_status(struct hotplug_slot *slot, u8 *status);
98static void ibm_handle_events(acpi_handle handle, u32 event, void *context);
99static int ibm_get_table_from_acpi(char **bufp);
100static ssize_t ibm_read_apci_table(struct file *filp, struct kobject *kobj,
101 struct bin_attribute *bin_attr,
102 char *buffer, loff_t pos, size_t size);
103static acpi_status __init ibm_find_acpi_device(acpi_handle handle,
104 u32 lvl, void *context, void **rv);
105static int __init ibm_acpiphp_init(void);
106static void __exit ibm_acpiphp_exit(void);
107
108static acpi_handle ibm_acpi_handle;
109static struct notification ibm_note;
110static struct bin_attribute ibm_apci_table_attr = {
111 .attr = {
112 .name = "apci_table",
113 .mode = S_IRUGO,
114 },
115 .read = ibm_read_apci_table,
116 .write = NULL,
117};
118static struct acpiphp_attention_info ibm_attention_info =
119{
120 .set_attn = ibm_set_attention_status,
121 .get_attn = ibm_get_attention_status,
122 .owner = THIS_MODULE,
123};
124
125/**
126 * ibm_slot_from_id - workaround for bad ibm hardware
127 * @id: the slot number that linux refers to the slot by
128 *
129 * Description: This method returns the aCPI slot descriptor
130 * corresponding to the Linux slot number. This descriptor
131 * has info about the aPCI slot id and attention status.
132 * This descriptor must be freed using kfree when done.
133 */
134static union apci_descriptor *ibm_slot_from_id(int id)
135{
136 int ind = 0, size;
137 union apci_descriptor *ret = NULL, *des;
138 char *table;
139
140 size = ibm_get_table_from_acpi(&table);
141 des = (union apci_descriptor *)table;
142 if (memcmp(des->header.sig, "aPCI", 4) != 0)
143 goto ibm_slot_done;
144
145 des = (union apci_descriptor *)&table[ind += des->header.len];
146 while (ind < size && (des->generic.type != 0x82 ||
147 des->slot.slot_num != id)) {
148 des = (union apci_descriptor *)&table[ind += des->generic.len];
149 }
150
151 if (ind < size && des->slot.slot_num == id)
152 ret = des;
153
154ibm_slot_done:
155 if (ret) {
156 ret = kmalloc(sizeof(union apci_descriptor), GFP_KERNEL);
157 memcpy(ret, des, sizeof(union apci_descriptor));
158 }
159 kfree(table);
160 return ret;
161}
162
163/**
164 * ibm_set_attention_status - callback method to set the attention LED
165 * @slot: the hotplug_slot to work with
166 * @status: what to set the LED to (0 or 1)
167 *
168 * Description: This method is registered with the acpiphp module as a
169 * callback to do the device specific task of setting the LED status.
170 */
171static int ibm_set_attention_status(struct hotplug_slot *slot, u8 status)
172{
173 union acpi_object args[2];
174 struct acpi_object_list params = { .pointer = args, .count = 2 };
175 acpi_status stat;
176 unsigned long long rc;
177 union apci_descriptor *ibm_slot;
178
179 ibm_slot = ibm_slot_from_id(hpslot_to_sun(slot));
180
181 pr_debug("%s: set slot %d (%d) attention status to %d\n", __func__,
182 ibm_slot->slot.slot_num, ibm_slot->slot.slot_id,
183 (status ? 1 : 0));
184
185 args[0].type = ACPI_TYPE_INTEGER;
186 args[0].integer.value = ibm_slot->slot.slot_id;
187 args[1].type = ACPI_TYPE_INTEGER;
188 args[1].integer.value = (status) ? 1 : 0;
189
190 kfree(ibm_slot);
191
192 stat = acpi_evaluate_integer(ibm_acpi_handle, "APLS", ¶ms, &rc);
193 if (ACPI_FAILURE(stat)) {
194 pr_err("APLS evaluation failed: 0x%08x\n", stat);
195 return -ENODEV;
196 } else if (!rc) {
197 pr_err("APLS method failed: 0x%08llx\n", rc);
198 return -ERANGE;
199 }
200 return 0;
201}
202
203/**
204 * ibm_get_attention_status - callback method to get attention LED status
205 * @slot: the hotplug_slot to work with
206 * @status: returns what the LED is set to (0 or 1)
207 *
208 * Description: This method is registered with the acpiphp module as a
209 * callback to do the device specific task of getting the LED status.
210 *
211 * Because there is no direct method of getting the LED status directly
212 * from an ACPI call, we read the aPCI table and parse out our
213 * slot descriptor to read the status from that.
214 */
215static int ibm_get_attention_status(struct hotplug_slot *slot, u8 *status)
216{
217 union apci_descriptor *ibm_slot;
218
219 ibm_slot = ibm_slot_from_id(hpslot_to_sun(slot));
220
221 if (ibm_slot->slot.attn & 0xa0 || ibm_slot->slot.status[1] & 0x08)
222 *status = 1;
223 else
224 *status = 0;
225
226 pr_debug("%s: get slot %d (%d) attention status is %d\n", __func__,
227 ibm_slot->slot.slot_num, ibm_slot->slot.slot_id,
228 *status);
229
230 kfree(ibm_slot);
231 return 0;
232}
233
234/**
235 * ibm_handle_events - listens for ACPI events for the IBM37D0 device
236 * @handle: an ACPI handle to the device that caused the event
237 * @event: the event info (device specific)
238 * @context: passed context (our notification struct)
239 *
240 * Description: This method is registered as a callback with the ACPI
241 * subsystem it is called when this device has an event to notify the OS of.
242 *
243 * The events actually come from the device as two events that get
244 * synthesized into one event with data by this function. The event
245 * ID comes first and then the slot number that caused it. We report
246 * this as one event to the OS.
247 *
248 * From section 5.6.2.2 of the ACPI 2.0 spec, I understand that the OSPM will
249 * only re-enable the interrupt that causes this event AFTER this method
250 * has returned, thereby enforcing serial access for the notification struct.
251 */
252static void ibm_handle_events(acpi_handle handle, u32 event, void *context)
253{
254 u8 detail = event & 0x0f;
255 u8 subevent = event & 0xf0;
256 struct notification *note = context;
257
258 pr_debug("%s: Received notification %02x\n", __func__, event);
259
260 if (subevent == 0x80) {
261 pr_debug("%s: generating bus event\n", __func__);
262 acpi_bus_generate_netlink_event(note->device->pnp.device_class,
263 dev_name(¬e->device->dev),
264 note->event, detail);
265 } else
266 note->event = event;
267}
268
269/**
270 * ibm_get_table_from_acpi - reads the APLS buffer from ACPI
271 * @bufp: address to pointer to allocate for the table
272 *
273 * Description: This method reads the APLS buffer in from ACPI and
274 * stores the "stripped" table into a single buffer
275 * it allocates and passes the address back in bufp.
276 *
277 * If NULL is passed in as buffer, this method only calculates
278 * the size of the table and returns that without filling
279 * in the buffer.
280 *
281 * Returns < 0 on error or the size of the table on success.
282 */
283static int ibm_get_table_from_acpi(char **bufp)
284{
285 union acpi_object *package;
286 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
287 acpi_status status;
288 char *lbuf = NULL;
289 int i, size = -EIO;
290
291 status = acpi_evaluate_object(ibm_acpi_handle, "APCI", NULL, &buffer);
292 if (ACPI_FAILURE(status)) {
293 pr_err("%s: APCI evaluation failed\n", __func__);
294 return -ENODEV;
295 }
296
297 package = (union acpi_object *) buffer.pointer;
298 if (!(package) ||
299 (package->type != ACPI_TYPE_PACKAGE) ||
300 !(package->package.elements)) {
301 pr_err("%s: Invalid APCI object\n", __func__);
302 goto read_table_done;
303 }
304
305 for(size = 0, i = 0; i < package->package.count; i++) {
306 if (package->package.elements[i].type != ACPI_TYPE_BUFFER) {
307 pr_err("%s: Invalid APCI element %d\n", __func__, i);
308 goto read_table_done;
309 }
310 size += package->package.elements[i].buffer.length;
311 }
312
313 if (bufp == NULL)
314 goto read_table_done;
315
316 lbuf = kzalloc(size, GFP_KERNEL);
317 pr_debug("%s: element count: %i, ASL table size: %i, &table = 0x%p\n",
318 __func__, package->package.count, size, lbuf);
319
320 if (lbuf) {
321 *bufp = lbuf;
322 } else {
323 size = -ENOMEM;
324 goto read_table_done;
325 }
326
327 size = 0;
328 for (i=0; i<package->package.count; i++) {
329 memcpy(&lbuf[size],
330 package->package.elements[i].buffer.pointer,
331 package->package.elements[i].buffer.length);
332 size += package->package.elements[i].buffer.length;
333 }
334
335read_table_done:
336 kfree(buffer.pointer);
337 return size;
338}
339
340/**
341 * ibm_read_apci_table - callback for the sysfs apci_table file
342 * @filp: the open sysfs file
343 * @kobj: the kobject this binary attribute is a part of
344 * @bin_attr: struct bin_attribute for this file
345 * @buffer: the kernel space buffer to fill
346 * @pos: the offset into the file
347 * @size: the number of bytes requested
348 *
349 * Description: Gets registered with sysfs as the reader callback
350 * to be executed when /sys/bus/pci/slots/apci_table gets read.
351 *
352 * Since we don't get notified on open and close for this file,
353 * things get really tricky here...
354 * our solution is to only allow reading the table in all at once.
355 */
356static ssize_t ibm_read_apci_table(struct file *filp, struct kobject *kobj,
357 struct bin_attribute *bin_attr,
358 char *buffer, loff_t pos, size_t size)
359{
360 int bytes_read = -EINVAL;
361 char *table = NULL;
362
363 pr_debug("%s: pos = %d, size = %zd\n", __func__, (int)pos, size);
364
365 if (pos == 0) {
366 bytes_read = ibm_get_table_from_acpi(&table);
367 if (bytes_read > 0 && bytes_read <= size)
368 memcpy(buffer, table, bytes_read);
369 kfree(table);
370 }
371 return bytes_read;
372}
373
374/**
375 * ibm_find_acpi_device - callback to find our ACPI device
376 * @handle: the ACPI handle of the device we are inspecting
377 * @lvl: depth into the namespace tree
378 * @context: a pointer to our handle to fill when we find the device
379 * @rv: a return value to fill if desired
380 *
381 * Description: Used as a callback when calling acpi_walk_namespace
382 * to find our device. When this method returns non-zero
383 * acpi_walk_namespace quits its search and returns our value.
384 */
385static acpi_status __init ibm_find_acpi_device(acpi_handle handle,
386 u32 lvl, void *context, void **rv)
387{
388 acpi_handle *phandle = (acpi_handle *)context;
389 acpi_status status;
390 struct acpi_device_info *info;
391 int retval = 0;
392
393 status = acpi_get_object_info(handle, &info);
394 if (ACPI_FAILURE(status)) {
395 pr_err("%s: Failed to get device information status=0x%x\n",
396 __func__, status);
397 return retval;
398 }
399
400 if (info->current_status && (info->valid & ACPI_VALID_HID) &&
401 (!strcmp(info->hardware_id.string, IBM_HARDWARE_ID1) ||
402 !strcmp(info->hardware_id.string, IBM_HARDWARE_ID2))) {
403 pr_debug("found hardware: %s, handle: %p\n",
404 info->hardware_id.string, handle);
405 *phandle = handle;
406 /* returning non-zero causes the search to stop
407 * and returns this value to the caller of
408 * acpi_walk_namespace, but it also causes some warnings
409 * in the acpi debug code to print...
410 */
411 retval = FOUND_APCI;
412 }
413 kfree(info);
414 return retval;
415}
416
417static int __init ibm_acpiphp_init(void)
418{
419 int retval = 0;
420 acpi_status status;
421 struct acpi_device *device;
422 struct kobject *sysdir = &pci_slots_kset->kobj;
423
424 pr_debug("%s\n", __func__);
425
426 if (acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
427 ACPI_UINT32_MAX, ibm_find_acpi_device, NULL,
428 &ibm_acpi_handle, NULL) != FOUND_APCI) {
429 pr_err("%s: acpi_walk_namespace failed\n", __func__);
430 retval = -ENODEV;
431 goto init_return;
432 }
433 pr_debug("%s: found IBM aPCI device\n", __func__);
434 if (acpi_bus_get_device(ibm_acpi_handle, &device)) {
435 pr_err("%s: acpi_bus_get_device failed\n", __func__);
436 retval = -ENODEV;
437 goto init_return;
438 }
439 if (acpiphp_register_attention(&ibm_attention_info)) {
440 retval = -ENODEV;
441 goto init_return;
442 }
443
444 ibm_note.device = device;
445 status = acpi_install_notify_handler(ibm_acpi_handle,
446 ACPI_DEVICE_NOTIFY, ibm_handle_events,
447 &ibm_note);
448 if (ACPI_FAILURE(status)) {
449 pr_err("%s: Failed to register notification handler\n",
450 __func__);
451 retval = -EBUSY;
452 goto init_cleanup;
453 }
454
455 ibm_apci_table_attr.size = ibm_get_table_from_acpi(NULL);
456 retval = sysfs_create_bin_file(sysdir, &ibm_apci_table_attr);
457
458 return retval;
459
460init_cleanup:
461 acpiphp_unregister_attention(&ibm_attention_info);
462init_return:
463 return retval;
464}
465
466static void __exit ibm_acpiphp_exit(void)
467{
468 acpi_status status;
469 struct kobject *sysdir = &pci_slots_kset->kobj;
470
471 pr_debug("%s\n", __func__);
472
473 if (acpiphp_unregister_attention(&ibm_attention_info))
474 pr_err("%s: attention info deregistration failed", __func__);
475
476 status = acpi_remove_notify_handler(
477 ibm_acpi_handle,
478 ACPI_DEVICE_NOTIFY,
479 ibm_handle_events);
480 if (ACPI_FAILURE(status))
481 pr_err("%s: Notification handler removal failed\n", __func__);
482 /* remove the /sys entries */
483 sysfs_remove_bin_file(sysdir, &ibm_apci_table_attr);
484}
485
486module_init(ibm_acpiphp_init);
487module_exit(ibm_acpiphp_exit);