USB: fix NULL pointer dereference on drivers/usb/serial/whiteheat.c
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / acpi / toshiba_acpi.c
blob9e8c20c6a0b7243e708876a4dfffa30dd8f47506
1 /*
2 * toshiba_acpi.c - Toshiba Laptop ACPI Extras
5 * Copyright (C) 2002-2004 John Belmonte
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 * The devolpment page for this driver is located at
23 * http://memebeam.org/toys/ToshibaAcpiDriver.
25 * Credits:
26 * Jonathan A. Buzzard - Toshiba HCI info, and critical tips on reverse
27 * engineering the Windows drivers
28 * Yasushi Nagato - changes for linux kernel 2.4 -> 2.5
29 * Rob Miller - TV out and hotkeys help
32 * TODO
36 #define TOSHIBA_ACPI_VERSION "0.18"
37 #define PROC_INTERFACE_VERSION 1
39 #include <linux/kernel.h>
40 #include <linux/module.h>
41 #include <linux/init.h>
42 #include <linux/types.h>
43 #include <linux/proc_fs.h>
44 #include <linux/backlight.h>
46 #include <asm/uaccess.h>
48 #include <acpi/acpi_drivers.h>
50 MODULE_AUTHOR("John Belmonte");
51 MODULE_DESCRIPTION("Toshiba Laptop ACPI Extras Driver");
52 MODULE_LICENSE("GPL");
54 #define MY_LOGPREFIX "toshiba_acpi: "
55 #define MY_ERR KERN_ERR MY_LOGPREFIX
56 #define MY_NOTICE KERN_NOTICE MY_LOGPREFIX
57 #define MY_INFO KERN_INFO MY_LOGPREFIX
59 /* Toshiba ACPI method paths */
60 #define METHOD_LCD_BRIGHTNESS "\\_SB_.PCI0.VGA_.LCD_._BCM"
61 #define METHOD_HCI_1 "\\_SB_.VALD.GHCI"
62 #define METHOD_HCI_2 "\\_SB_.VALZ.GHCI"
63 #define METHOD_VIDEO_OUT "\\_SB_.VALX.DSSX"
65 /* Toshiba HCI interface definitions
67 * HCI is Toshiba's "Hardware Control Interface" which is supposed to
68 * be uniform across all their models. Ideally we would just call
69 * dedicated ACPI methods instead of using this primitive interface.
70 * However the ACPI methods seem to be incomplete in some areas (for
71 * example they allow setting, but not reading, the LCD brightness value),
72 * so this is still useful.
75 #define HCI_WORDS 6
77 /* operations */
78 #define HCI_SET 0xff00
79 #define HCI_GET 0xfe00
81 /* return codes */
82 #define HCI_SUCCESS 0x0000
83 #define HCI_FAILURE 0x1000
84 #define HCI_NOT_SUPPORTED 0x8000
85 #define HCI_EMPTY 0x8c00
87 /* registers */
88 #define HCI_FAN 0x0004
89 #define HCI_SYSTEM_EVENT 0x0016
90 #define HCI_VIDEO_OUT 0x001c
91 #define HCI_HOTKEY_EVENT 0x001e
92 #define HCI_LCD_BRIGHTNESS 0x002a
94 /* field definitions */
95 #define HCI_LCD_BRIGHTNESS_BITS 3
96 #define HCI_LCD_BRIGHTNESS_SHIFT (16-HCI_LCD_BRIGHTNESS_BITS)
97 #define HCI_LCD_BRIGHTNESS_LEVELS (1 << HCI_LCD_BRIGHTNESS_BITS)
98 #define HCI_VIDEO_OUT_LCD 0x1
99 #define HCI_VIDEO_OUT_CRT 0x2
100 #define HCI_VIDEO_OUT_TV 0x4
102 /* utility
105 static __inline__ void _set_bit(u32 * word, u32 mask, int value)
107 *word = (*word & ~mask) | (mask * value);
110 /* acpi interface wrappers
113 static int is_valid_acpi_path(const char *methodName)
115 acpi_handle handle;
116 acpi_status status;
118 status = acpi_get_handle(NULL, (char *)methodName, &handle);
119 return !ACPI_FAILURE(status);
122 static int write_acpi_int(const char *methodName, int val)
124 struct acpi_object_list params;
125 union acpi_object in_objs[1];
126 acpi_status status;
128 params.count = ARRAY_SIZE(in_objs);
129 params.pointer = in_objs;
130 in_objs[0].type = ACPI_TYPE_INTEGER;
131 in_objs[0].integer.value = val;
133 status = acpi_evaluate_object(NULL, (char *)methodName, &params, NULL);
134 return (status == AE_OK);
137 #if 0
138 static int read_acpi_int(const char *methodName, int *pVal)
140 struct acpi_buffer results;
141 union acpi_object out_objs[1];
142 acpi_status status;
144 results.length = sizeof(out_objs);
145 results.pointer = out_objs;
147 status = acpi_evaluate_object(0, (char *)methodName, 0, &results);
148 *pVal = out_objs[0].integer.value;
150 return (status == AE_OK) && (out_objs[0].type == ACPI_TYPE_INTEGER);
152 #endif
154 static const char *method_hci /*= 0*/ ;
156 /* Perform a raw HCI call. Here we don't care about input or output buffer
157 * format.
159 static acpi_status hci_raw(const u32 in[HCI_WORDS], u32 out[HCI_WORDS])
161 struct acpi_object_list params;
162 union acpi_object in_objs[HCI_WORDS];
163 struct acpi_buffer results;
164 union acpi_object out_objs[HCI_WORDS + 1];
165 acpi_status status;
166 int i;
168 params.count = HCI_WORDS;
169 params.pointer = in_objs;
170 for (i = 0; i < HCI_WORDS; ++i) {
171 in_objs[i].type = ACPI_TYPE_INTEGER;
172 in_objs[i].integer.value = in[i];
175 results.length = sizeof(out_objs);
176 results.pointer = out_objs;
178 status = acpi_evaluate_object(NULL, (char *)method_hci, &params,
179 &results);
180 if ((status == AE_OK) && (out_objs->package.count <= HCI_WORDS)) {
181 for (i = 0; i < out_objs->package.count; ++i) {
182 out[i] = out_objs->package.elements[i].integer.value;
186 return status;
189 /* common hci tasks (get or set one value)
191 * In addition to the ACPI status, the HCI system returns a result which
192 * may be useful (such as "not supported").
195 static acpi_status hci_write1(u32 reg, u32 in1, u32 * result)
197 u32 in[HCI_WORDS] = { HCI_SET, reg, in1, 0, 0, 0 };
198 u32 out[HCI_WORDS];
199 acpi_status status = hci_raw(in, out);
200 *result = (status == AE_OK) ? out[0] : HCI_FAILURE;
201 return status;
204 static acpi_status hci_read1(u32 reg, u32 * out1, u32 * result)
206 u32 in[HCI_WORDS] = { HCI_GET, reg, 0, 0, 0, 0 };
207 u32 out[HCI_WORDS];
208 acpi_status status = hci_raw(in, out);
209 *out1 = out[2];
210 *result = (status == AE_OK) ? out[0] : HCI_FAILURE;
211 return status;
214 static struct proc_dir_entry *toshiba_proc_dir /*= 0*/ ;
215 static struct backlight_device *toshiba_backlight_device;
216 static int force_fan;
217 static int last_key_event;
218 static int key_event_valid;
220 typedef struct _ProcItem {
221 const char *name;
222 char *(*read_func) (char *);
223 unsigned long (*write_func) (const char *, unsigned long);
224 } ProcItem;
226 /* proc file handlers
229 static int
230 dispatch_read(char *page, char **start, off_t off, int count, int *eof,
231 ProcItem * item)
233 char *p = page;
234 int len;
236 if (off == 0)
237 p = item->read_func(p);
239 /* ISSUE: I don't understand this code */
240 len = (p - page);
241 if (len <= off + count)
242 *eof = 1;
243 *start = page + off;
244 len -= off;
245 if (len > count)
246 len = count;
247 if (len < 0)
248 len = 0;
249 return len;
252 static int
253 dispatch_write(struct file *file, const char __user * buffer,
254 unsigned long count, ProcItem * item)
256 int result;
257 char *tmp_buffer;
259 /* Arg buffer points to userspace memory, which can't be accessed
260 * directly. Since we're making a copy, zero-terminate the
261 * destination so that sscanf can be used on it safely.
263 tmp_buffer = kmalloc(count + 1, GFP_KERNEL);
264 if (!tmp_buffer)
265 return -ENOMEM;
267 if (copy_from_user(tmp_buffer, buffer, count)) {
268 result = -EFAULT;
269 } else {
270 tmp_buffer[count] = 0;
271 result = item->write_func(tmp_buffer, count);
273 kfree(tmp_buffer);
274 return result;
277 static int get_lcd(struct backlight_device *bd)
279 u32 hci_result;
280 u32 value;
282 hci_read1(HCI_LCD_BRIGHTNESS, &value, &hci_result);
283 if (hci_result == HCI_SUCCESS) {
284 return (value >> HCI_LCD_BRIGHTNESS_SHIFT);
285 } else
286 return -EFAULT;
289 static char *read_lcd(char *p)
291 int value = get_lcd(NULL);
293 if (value >= 0) {
294 p += sprintf(p, "brightness: %d\n", value);
295 p += sprintf(p, "brightness_levels: %d\n",
296 HCI_LCD_BRIGHTNESS_LEVELS);
297 } else {
298 printk(MY_ERR "Error reading LCD brightness\n");
301 return p;
304 static int set_lcd(int value)
306 u32 hci_result;
308 value = value << HCI_LCD_BRIGHTNESS_SHIFT;
309 hci_write1(HCI_LCD_BRIGHTNESS, value, &hci_result);
310 if (hci_result != HCI_SUCCESS)
311 return -EFAULT;
313 return 0;
316 static int set_lcd_status(struct backlight_device *bd)
318 return set_lcd(bd->props.brightness);
321 static unsigned long write_lcd(const char *buffer, unsigned long count)
323 int value;
324 int ret;
326 if (sscanf(buffer, " brightness : %i", &value) == 1 &&
327 value >= 0 && value < HCI_LCD_BRIGHTNESS_LEVELS) {
328 ret = set_lcd(value);
329 if (ret == 0)
330 ret = count;
331 } else {
332 ret = -EINVAL;
334 return ret;
337 static char *read_video(char *p)
339 u32 hci_result;
340 u32 value;
342 hci_read1(HCI_VIDEO_OUT, &value, &hci_result);
343 if (hci_result == HCI_SUCCESS) {
344 int is_lcd = (value & HCI_VIDEO_OUT_LCD) ? 1 : 0;
345 int is_crt = (value & HCI_VIDEO_OUT_CRT) ? 1 : 0;
346 int is_tv = (value & HCI_VIDEO_OUT_TV) ? 1 : 0;
347 p += sprintf(p, "lcd_out: %d\n", is_lcd);
348 p += sprintf(p, "crt_out: %d\n", is_crt);
349 p += sprintf(p, "tv_out: %d\n", is_tv);
350 } else {
351 printk(MY_ERR "Error reading video out status\n");
354 return p;
357 static unsigned long write_video(const char *buffer, unsigned long count)
359 int value;
360 int remain = count;
361 int lcd_out = -1;
362 int crt_out = -1;
363 int tv_out = -1;
364 u32 hci_result;
365 u32 video_out;
367 /* scan expression. Multiple expressions may be delimited with ;
369 * NOTE: to keep scanning simple, invalid fields are ignored
371 while (remain) {
372 if (sscanf(buffer, " lcd_out : %i", &value) == 1)
373 lcd_out = value & 1;
374 else if (sscanf(buffer, " crt_out : %i", &value) == 1)
375 crt_out = value & 1;
376 else if (sscanf(buffer, " tv_out : %i", &value) == 1)
377 tv_out = value & 1;
378 /* advance to one character past the next ; */
379 do {
380 ++buffer;
381 --remain;
383 while (remain && *(buffer - 1) != ';');
386 hci_read1(HCI_VIDEO_OUT, &video_out, &hci_result);
387 if (hci_result == HCI_SUCCESS) {
388 int new_video_out = video_out;
389 if (lcd_out != -1)
390 _set_bit(&new_video_out, HCI_VIDEO_OUT_LCD, lcd_out);
391 if (crt_out != -1)
392 _set_bit(&new_video_out, HCI_VIDEO_OUT_CRT, crt_out);
393 if (tv_out != -1)
394 _set_bit(&new_video_out, HCI_VIDEO_OUT_TV, tv_out);
395 /* To avoid unnecessary video disruption, only write the new
396 * video setting if something changed. */
397 if (new_video_out != video_out)
398 write_acpi_int(METHOD_VIDEO_OUT, new_video_out);
399 } else {
400 return -EFAULT;
403 return count;
406 static char *read_fan(char *p)
408 u32 hci_result;
409 u32 value;
411 hci_read1(HCI_FAN, &value, &hci_result);
412 if (hci_result == HCI_SUCCESS) {
413 p += sprintf(p, "running: %d\n", (value > 0));
414 p += sprintf(p, "force_on: %d\n", force_fan);
415 } else {
416 printk(MY_ERR "Error reading fan status\n");
419 return p;
422 static unsigned long write_fan(const char *buffer, unsigned long count)
424 int value;
425 u32 hci_result;
427 if (sscanf(buffer, " force_on : %i", &value) == 1 &&
428 value >= 0 && value <= 1) {
429 hci_write1(HCI_FAN, value, &hci_result);
430 if (hci_result != HCI_SUCCESS)
431 return -EFAULT;
432 else
433 force_fan = value;
434 } else {
435 return -EINVAL;
438 return count;
441 static char *read_keys(char *p)
443 u32 hci_result;
444 u32 value;
446 if (!key_event_valid) {
447 hci_read1(HCI_SYSTEM_EVENT, &value, &hci_result);
448 if (hci_result == HCI_SUCCESS) {
449 key_event_valid = 1;
450 last_key_event = value;
451 } else if (hci_result == HCI_EMPTY) {
452 /* better luck next time */
453 } else if (hci_result == HCI_NOT_SUPPORTED) {
454 /* This is a workaround for an unresolved issue on
455 * some machines where system events sporadically
456 * become disabled. */
457 hci_write1(HCI_SYSTEM_EVENT, 1, &hci_result);
458 printk(MY_NOTICE "Re-enabled hotkeys\n");
459 } else {
460 printk(MY_ERR "Error reading hotkey status\n");
461 goto end;
465 p += sprintf(p, "hotkey_ready: %d\n", key_event_valid);
466 p += sprintf(p, "hotkey: 0x%04x\n", last_key_event);
468 end:
469 return p;
472 static unsigned long write_keys(const char *buffer, unsigned long count)
474 int value;
476 if (sscanf(buffer, " hotkey_ready : %i", &value) == 1 && value == 0) {
477 key_event_valid = 0;
478 } else {
479 return -EINVAL;
482 return count;
485 static char *read_version(char *p)
487 p += sprintf(p, "driver: %s\n", TOSHIBA_ACPI_VERSION);
488 p += sprintf(p, "proc_interface: %d\n",
489 PROC_INTERFACE_VERSION);
490 return p;
493 /* proc and module init
496 #define PROC_TOSHIBA "toshiba"
498 static ProcItem proc_items[] = {
499 {"lcd", read_lcd, write_lcd},
500 {"video", read_video, write_video},
501 {"fan", read_fan, write_fan},
502 {"keys", read_keys, write_keys},
503 {"version", read_version, NULL},
504 {NULL}
507 static acpi_status __init add_device(void)
509 struct proc_dir_entry *proc;
510 ProcItem *item;
512 for (item = proc_items; item->name; ++item) {
513 proc = create_proc_read_entry(item->name,
514 S_IFREG | S_IRUGO | S_IWUSR,
515 toshiba_proc_dir,
516 (read_proc_t *) dispatch_read,
517 item);
518 if (proc)
519 proc->owner = THIS_MODULE;
520 if (proc && item->write_func)
521 proc->write_proc = (write_proc_t *) dispatch_write;
524 return AE_OK;
527 static acpi_status remove_device(void)
529 ProcItem *item;
531 for (item = proc_items; item->name; ++item)
532 remove_proc_entry(item->name, toshiba_proc_dir);
533 return AE_OK;
536 static struct backlight_ops toshiba_backlight_data = {
537 .get_brightness = get_lcd,
538 .update_status = set_lcd_status,
541 static void toshiba_acpi_exit(void)
543 if (toshiba_backlight_device)
544 backlight_device_unregister(toshiba_backlight_device);
546 remove_device();
548 if (toshiba_proc_dir)
549 remove_proc_entry(PROC_TOSHIBA, acpi_root_dir);
551 return;
554 static int __init toshiba_acpi_init(void)
556 acpi_status status = AE_OK;
557 u32 hci_result;
559 if (acpi_disabled)
560 return -ENODEV;
562 /* simple device detection: look for HCI method */
563 if (is_valid_acpi_path(METHOD_HCI_1))
564 method_hci = METHOD_HCI_1;
565 else if (is_valid_acpi_path(METHOD_HCI_2))
566 method_hci = METHOD_HCI_2;
567 else
568 return -ENODEV;
570 printk(MY_INFO "Toshiba Laptop ACPI Extras version %s\n",
571 TOSHIBA_ACPI_VERSION);
572 printk(MY_INFO " HCI method: %s\n", method_hci);
574 force_fan = 0;
575 key_event_valid = 0;
577 /* enable event fifo */
578 hci_write1(HCI_SYSTEM_EVENT, 1, &hci_result);
580 toshiba_proc_dir = proc_mkdir(PROC_TOSHIBA, acpi_root_dir);
581 if (!toshiba_proc_dir) {
582 status = AE_ERROR;
583 } else {
584 toshiba_proc_dir->owner = THIS_MODULE;
585 status = add_device();
586 if (ACPI_FAILURE(status))
587 remove_proc_entry(PROC_TOSHIBA, acpi_root_dir);
590 toshiba_backlight_device = backlight_device_register("toshiba",NULL,
591 NULL,
592 &toshiba_backlight_data);
593 if (IS_ERR(toshiba_backlight_device)) {
594 int ret = PTR_ERR(toshiba_backlight_device);
596 printk(KERN_ERR "Could not register toshiba backlight device\n");
597 toshiba_backlight_device = NULL;
598 toshiba_acpi_exit();
599 return ret;
601 toshiba_backlight_device->props.max_brightness = HCI_LCD_BRIGHTNESS_LEVELS - 1;
603 return (ACPI_SUCCESS(status)) ? 0 : -ENODEV;
606 module_init(toshiba_acpi_init);
607 module_exit(toshiba_acpi_exit);