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