fix a kmap leak in virtio_console
[linux/fpc-iii.git] / drivers / pci / hotplug / acpiphp_ibm.c
blob8dcccffd6e216b8529da5530019fe557e0f61ff1
1 /*
2 * ACPI PCI Hot Plug IBM Extension
4 * Copyright (C) 2004 Vernon Mauery <vernux@us.ibm.com>
5 * Copyright (C) 2004 IBM Corp.
7 * All rights reserved.
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
18 * details.
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 <asm/uaccess.h>
40 #include "acpiphp.h"
41 #include "../pci.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
62 * aPCI table
64 union 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;
88 /* struct notification - keeps info about the device
89 * that cause the ACPI notification event
91 struct notification {
92 struct acpi_device *device;
93 u8 event;
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 = {
111 .attr = {
112 .name = "apci_table",
113 .mode = S_IRUGO,
115 .read = ibm_read_apci_table,
116 .write = NULL,
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)
136 int ind = 0, size;
137 union apci_descriptor *ret = NULL, *des;
138 char *table;
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;
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];
151 if (ind < size && des->slot.slot_num == id)
152 ret = des;
154 ibm_slot_done:
155 if (ret) {
156 ret = kmalloc(sizeof(union apci_descriptor), GFP_KERNEL);
157 memcpy(ret, des, sizeof(union apci_descriptor));
159 kfree(table);
160 return ret;
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)
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.
171 static int ibm_set_attention_status(struct hotplug_slot *slot, u8 status)
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;
179 ibm_slot = ibm_slot_from_id(hpslot_to_sun(slot));
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));
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;
190 kfree(ibm_slot);
192 stat = acpi_evaluate_integer(ibm_acpi_handle, "APLS", &params, &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;
200 return 0;
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)
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.
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.
215 static int ibm_get_attention_status(struct hotplug_slot *slot, u8 *status)
217 union apci_descriptor *ibm_slot;
219 ibm_slot = ibm_slot_from_id(hpslot_to_sun(slot));
221 if (ibm_slot->slot.attn & 0xa0 || ibm_slot->slot.status[1] & 0x08)
222 *status = 1;
223 else
224 *status = 0;
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);
230 kfree(ibm_slot);
231 return 0;
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)
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.
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.
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.
252 static void ibm_handle_events(acpi_handle handle, u32 event, void *context)
254 u8 detail = event & 0x0f;
255 u8 subevent = event & 0xf0;
256 struct notification *note = context;
258 pr_debug("%s: Received notification %02x\n", __func__, event);
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(&note->device->dev),
264 note->event, detail);
265 } else
266 note->event = event;
270 * ibm_get_table_from_acpi - reads the APLS buffer from ACPI
271 * @bufp: address to pointer to allocate for the table
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.
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.
281 * Returns < 0 on error or the size of the table on success.
283 static int ibm_get_table_from_acpi(char **bufp)
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;
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;
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;
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;
310 size += package->package.elements[i].buffer.length;
313 if (bufp == NULL)
314 goto read_table_done;
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);
320 if (lbuf) {
321 *bufp = lbuf;
322 } else {
323 size = -ENOMEM;
324 goto read_table_done;
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;
335 read_table_done:
336 kfree(buffer.pointer);
337 return size;
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
349 * Description: Gets registered with sysfs as the reader callback
350 * to be executed when /sys/bus/pci/slots/apci_table gets read.
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.
356 static 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)
360 int bytes_read = -EINVAL;
361 char *table = NULL;
363 pr_debug("%s: pos = %d, size = %zd\n", __func__, (int)pos, size);
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);
371 return bytes_read;
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
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.
385 static acpi_status __init ibm_find_acpi_device(acpi_handle handle,
386 u32 lvl, void *context, void **rv)
388 acpi_handle *phandle = (acpi_handle *)context;
389 acpi_status status;
390 struct acpi_device_info *info;
391 int retval = 0;
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;
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...
411 retval = FOUND_APCI;
413 kfree(info);
414 return retval;
417 static int __init ibm_acpiphp_init(void)
419 int retval = 0;
420 acpi_status status;
421 struct acpi_device *device;
422 struct kobject *sysdir = &pci_slots_kset->kobj;
424 pr_debug("%s\n", __func__);
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;
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;
439 if (acpiphp_register_attention(&ibm_attention_info)) {
440 retval = -ENODEV;
441 goto init_return;
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;
455 ibm_apci_table_attr.size = ibm_get_table_from_acpi(NULL);
456 retval = sysfs_create_bin_file(sysdir, &ibm_apci_table_attr);
458 return retval;
460 init_cleanup:
461 acpiphp_unregister_attention(&ibm_attention_info);
462 init_return:
463 return retval;
466 static void __exit ibm_acpiphp_exit(void)
468 acpi_status status;
469 struct kobject *sysdir = &pci_slots_kset->kobj;
471 pr_debug("%s\n", __func__);
473 if (acpiphp_unregister_attention(&ibm_attention_info))
474 pr_err("%s: attention info deregistration failed", __func__);
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);
486 module_init(ibm_acpiphp_init);
487 module_exit(ibm_acpiphp_exit);