2 * ACPI PCI Hot Plug IBM Extension
4 * Copyright (C) 2004 Vernon Mauery <vernux@us.ibm.com>
5 * Copyright (C) 2004 IBM Corp.
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.
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
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.
24 * Send feedback to <vernux@us.ibm.com>
28 #define pr_fmt(fmt) "acpiphp_ibm: " fmt
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 <linux/uaccess.h>
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"
48 MODULE_AUTHOR(DRIVER_AUTHOR
);
49 MODULE_DESCRIPTION(DRIVER_DESC
);
50 MODULE_LICENSE("GPL");
51 MODULE_VERSION(DRIVER_VERSION
);
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"
58 #define hpslot_to_sun(A) (((struct slot *)((A)->private))->sun)
60 /* union apci_descriptor - allows access to the
61 * various device descriptors that are embedded in the
64 union apci_descriptor
{
88 /* struct notification - keeps info about the device
89 * that cause the ACPI notification event
92 struct acpi_device
*device
;
96 static int ibm_set_attention_status(struct hotplug_slot
*slot
, u8 status
);
97 static int ibm_get_attention_status(struct hotplug_slot
*slot
, u8
*status
);
98 static void ibm_handle_events(acpi_handle handle
, u32 event
, void *context
);
99 static int ibm_get_table_from_acpi(char **bufp
);
100 static 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
);
103 static acpi_status __init
ibm_find_acpi_device(acpi_handle handle
,
104 u32 lvl
, void *context
, void **rv
);
105 static int __init
ibm_acpiphp_init(void);
106 static void __exit
ibm_acpiphp_exit(void);
108 static acpi_handle ibm_acpi_handle
;
109 static struct notification ibm_note
;
110 static struct bin_attribute ibm_apci_table_attr
= {
112 .name
= "apci_table",
115 .read
= ibm_read_apci_table
,
118 static struct acpiphp_attention_info ibm_attention_info
=
120 .set_attn
= ibm_set_attention_status
,
121 .get_attn
= ibm_get_attention_status
,
122 .owner
= THIS_MODULE
,
126 * ibm_slot_from_id - workaround for bad ibm hardware
127 * @id: the slot number that linux refers to the slot by
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.
134 static union apci_descriptor
*ibm_slot_from_id(int id
)
137 union apci_descriptor
*ret
= NULL
, *des
;
140 size
= ibm_get_table_from_acpi(&table
);
143 des
= (union apci_descriptor
*)table
;
144 if (memcmp(des
->header
.sig
, "aPCI", 4) != 0)
147 des
= (union apci_descriptor
*)&table
[ind
+= des
->header
.len
];
148 while (ind
< size
&& (des
->generic
.type
!= 0x82 ||
149 des
->slot
.slot_num
!= id
)) {
150 des
= (union apci_descriptor
*)&table
[ind
+= des
->generic
.len
];
153 if (ind
< size
&& des
->slot
.slot_num
== id
)
158 ret
= kmalloc(sizeof(union apci_descriptor
), GFP_KERNEL
);
160 memcpy(ret
, des
, sizeof(union apci_descriptor
));
167 * ibm_set_attention_status - callback method to set the attention LED
168 * @slot: the hotplug_slot to work with
169 * @status: what to set the LED to (0 or 1)
171 * Description: This method is registered with the acpiphp module as a
172 * callback to do the device specific task of setting the LED status.
174 static int ibm_set_attention_status(struct hotplug_slot
*slot
, u8 status
)
176 union acpi_object args
[2];
177 struct acpi_object_list params
= { .pointer
= args
, .count
= 2 };
179 unsigned long long rc
;
180 union apci_descriptor
*ibm_slot
;
181 int id
= hpslot_to_sun(slot
);
183 ibm_slot
= ibm_slot_from_id(id
);
185 pr_err("APLS null ACPI descriptor for slot %d\n", id
);
189 pr_debug("%s: set slot %d (%d) attention status to %d\n", __func__
,
190 ibm_slot
->slot
.slot_num
, ibm_slot
->slot
.slot_id
,
193 args
[0].type
= ACPI_TYPE_INTEGER
;
194 args
[0].integer
.value
= ibm_slot
->slot
.slot_id
;
195 args
[1].type
= ACPI_TYPE_INTEGER
;
196 args
[1].integer
.value
= (status
) ? 1 : 0;
200 stat
= acpi_evaluate_integer(ibm_acpi_handle
, "APLS", ¶ms
, &rc
);
201 if (ACPI_FAILURE(stat
)) {
202 pr_err("APLS evaluation failed: 0x%08x\n", stat
);
205 pr_err("APLS method failed: 0x%08llx\n", rc
);
212 * ibm_get_attention_status - callback method to get attention LED status
213 * @slot: the hotplug_slot to work with
214 * @status: returns what the LED is set to (0 or 1)
216 * Description: This method is registered with the acpiphp module as a
217 * callback to do the device specific task of getting the LED status.
219 * Because there is no direct method of getting the LED status directly
220 * from an ACPI call, we read the aPCI table and parse out our
221 * slot descriptor to read the status from that.
223 static int ibm_get_attention_status(struct hotplug_slot
*slot
, u8
*status
)
225 union apci_descriptor
*ibm_slot
;
226 int id
= hpslot_to_sun(slot
);
228 ibm_slot
= ibm_slot_from_id(id
);
230 pr_err("APLS null ACPI descriptor for slot %d\n", id
);
234 if (ibm_slot
->slot
.attn
& 0xa0 || ibm_slot
->slot
.status
[1] & 0x08)
239 pr_debug("%s: get slot %d (%d) attention status is %d\n", __func__
,
240 ibm_slot
->slot
.slot_num
, ibm_slot
->slot
.slot_id
,
248 * ibm_handle_events - listens for ACPI events for the IBM37D0 device
249 * @handle: an ACPI handle to the device that caused the event
250 * @event: the event info (device specific)
251 * @context: passed context (our notification struct)
253 * Description: This method is registered as a callback with the ACPI
254 * subsystem it is called when this device has an event to notify the OS of.
256 * The events actually come from the device as two events that get
257 * synthesized into one event with data by this function. The event
258 * ID comes first and then the slot number that caused it. We report
259 * this as one event to the OS.
261 * From section 5.6.2.2 of the ACPI 2.0 spec, I understand that the OSPM will
262 * only re-enable the interrupt that causes this event AFTER this method
263 * has returned, thereby enforcing serial access for the notification struct.
265 static void ibm_handle_events(acpi_handle handle
, u32 event
, void *context
)
267 u8 detail
= event
& 0x0f;
268 u8 subevent
= event
& 0xf0;
269 struct notification
*note
= context
;
271 pr_debug("%s: Received notification %02x\n", __func__
, event
);
273 if (subevent
== 0x80) {
274 pr_debug("%s: generating bus event\n", __func__
);
275 acpi_bus_generate_netlink_event(note
->device
->pnp
.device_class
,
276 dev_name(¬e
->device
->dev
),
277 note
->event
, detail
);
283 * ibm_get_table_from_acpi - reads the APLS buffer from ACPI
284 * @bufp: address to pointer to allocate for the table
286 * Description: This method reads the APLS buffer in from ACPI and
287 * stores the "stripped" table into a single buffer
288 * it allocates and passes the address back in bufp.
290 * If NULL is passed in as buffer, this method only calculates
291 * the size of the table and returns that without filling
294 * Returns < 0 on error or the size of the table on success.
296 static int ibm_get_table_from_acpi(char **bufp
)
298 union acpi_object
*package
;
299 struct acpi_buffer buffer
= { ACPI_ALLOCATE_BUFFER
, NULL
};
304 status
= acpi_evaluate_object(ibm_acpi_handle
, "APCI", NULL
, &buffer
);
305 if (ACPI_FAILURE(status
)) {
306 pr_err("%s: APCI evaluation failed\n", __func__
);
310 package
= (union acpi_object
*) buffer
.pointer
;
312 (package
->type
!= ACPI_TYPE_PACKAGE
) ||
313 !(package
->package
.elements
)) {
314 pr_err("%s: Invalid APCI object\n", __func__
);
315 goto read_table_done
;
318 for (size
= 0, i
= 0; i
< package
->package
.count
; i
++) {
319 if (package
->package
.elements
[i
].type
!= ACPI_TYPE_BUFFER
) {
320 pr_err("%s: Invalid APCI element %d\n", __func__
, i
);
321 goto read_table_done
;
323 size
+= package
->package
.elements
[i
].buffer
.length
;
327 goto read_table_done
;
329 lbuf
= kzalloc(size
, GFP_KERNEL
);
330 pr_debug("%s: element count: %i, ASL table size: %i, &table = 0x%p\n",
331 __func__
, package
->package
.count
, size
, lbuf
);
337 goto read_table_done
;
341 for (i
= 0; i
< package
->package
.count
; i
++) {
343 package
->package
.elements
[i
].buffer
.pointer
,
344 package
->package
.elements
[i
].buffer
.length
);
345 size
+= package
->package
.elements
[i
].buffer
.length
;
349 kfree(buffer
.pointer
);
354 * ibm_read_apci_table - callback for the sysfs apci_table file
355 * @filp: the open sysfs file
356 * @kobj: the kobject this binary attribute is a part of
357 * @bin_attr: struct bin_attribute for this file
358 * @buffer: the kernel space buffer to fill
359 * @pos: the offset into the file
360 * @size: the number of bytes requested
362 * Description: Gets registered with sysfs as the reader callback
363 * to be executed when /sys/bus/pci/slots/apci_table gets read.
365 * Since we don't get notified on open and close for this file,
366 * things get really tricky here...
367 * our solution is to only allow reading the table in all at once.
369 static ssize_t
ibm_read_apci_table(struct file
*filp
, struct kobject
*kobj
,
370 struct bin_attribute
*bin_attr
,
371 char *buffer
, loff_t pos
, size_t size
)
373 int bytes_read
= -EINVAL
;
376 pr_debug("%s: pos = %d, size = %zd\n", __func__
, (int)pos
, size
);
379 bytes_read
= ibm_get_table_from_acpi(&table
);
380 if (bytes_read
> 0 && bytes_read
<= size
)
381 memcpy(buffer
, table
, bytes_read
);
388 * ibm_find_acpi_device - callback to find our ACPI device
389 * @handle: the ACPI handle of the device we are inspecting
390 * @lvl: depth into the namespace tree
391 * @context: a pointer to our handle to fill when we find the device
392 * @rv: a return value to fill if desired
394 * Description: Used as a callback when calling acpi_walk_namespace
395 * to find our device. When this method returns non-zero
396 * acpi_walk_namespace quits its search and returns our value.
398 static acpi_status __init
ibm_find_acpi_device(acpi_handle handle
,
399 u32 lvl
, void *context
, void **rv
)
401 acpi_handle
*phandle
= (acpi_handle
*)context
;
403 struct acpi_device_info
*info
;
406 status
= acpi_get_object_info(handle
, &info
);
407 if (ACPI_FAILURE(status
)) {
408 pr_err("%s: Failed to get device information status=0x%x\n",
413 if (info
->current_status
&& (info
->valid
& ACPI_VALID_HID
) &&
414 (!strcmp(info
->hardware_id
.string
, IBM_HARDWARE_ID1
) ||
415 !strcmp(info
->hardware_id
.string
, IBM_HARDWARE_ID2
))) {
416 pr_debug("found hardware: %s, handle: %p\n",
417 info
->hardware_id
.string
, handle
);
419 /* returning non-zero causes the search to stop
420 * and returns this value to the caller of
421 * acpi_walk_namespace, but it also causes some warnings
422 * in the acpi debug code to print...
430 static int __init
ibm_acpiphp_init(void)
434 struct acpi_device
*device
;
435 struct kobject
*sysdir
= &pci_slots_kset
->kobj
;
437 pr_debug("%s\n", __func__
);
439 if (acpi_walk_namespace(ACPI_TYPE_DEVICE
, ACPI_ROOT_OBJECT
,
440 ACPI_UINT32_MAX
, ibm_find_acpi_device
, NULL
,
441 &ibm_acpi_handle
, NULL
) != FOUND_APCI
) {
442 pr_err("%s: acpi_walk_namespace failed\n", __func__
);
446 pr_debug("%s: found IBM aPCI device\n", __func__
);
447 if (acpi_bus_get_device(ibm_acpi_handle
, &device
)) {
448 pr_err("%s: acpi_bus_get_device failed\n", __func__
);
452 if (acpiphp_register_attention(&ibm_attention_info
)) {
457 ibm_note
.device
= device
;
458 status
= acpi_install_notify_handler(ibm_acpi_handle
,
459 ACPI_DEVICE_NOTIFY
, ibm_handle_events
,
461 if (ACPI_FAILURE(status
)) {
462 pr_err("%s: Failed to register notification handler\n",
468 ibm_apci_table_attr
.size
= ibm_get_table_from_acpi(NULL
);
469 retval
= sysfs_create_bin_file(sysdir
, &ibm_apci_table_attr
);
474 acpiphp_unregister_attention(&ibm_attention_info
);
479 static void __exit
ibm_acpiphp_exit(void)
482 struct kobject
*sysdir
= &pci_slots_kset
->kobj
;
484 pr_debug("%s\n", __func__
);
486 if (acpiphp_unregister_attention(&ibm_attention_info
))
487 pr_err("%s: attention info deregistration failed", __func__
);
489 status
= acpi_remove_notify_handler(
493 if (ACPI_FAILURE(status
))
494 pr_err("%s: Notification handler removal failed\n", __func__
);
495 /* remove the /sys entries */
496 sysfs_remove_bin_file(sysdir
, &ibm_apci_table_attr
);
499 module_init(ibm_acpiphp_init
);
500 module_exit(ibm_acpiphp_exit
);