Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
[sfrench/cifs-2.6.git] / drivers / ide / ide-acpi.c
1 /*
2  * ide-acpi.c
3  * Provides ACPI support for IDE drives.
4  *
5  * Copyright (C) 2005 Intel Corp.
6  * Copyright (C) 2005 Randy Dunlap
7  * Copyright (C) 2006 SUSE Linux Products GmbH
8  * Copyright (C) 2006 Hannes Reinecke
9  */
10
11 #include <linux/ata.h>
12 #include <linux/delay.h>
13 #include <linux/device.h>
14 #include <linux/errno.h>
15 #include <linux/kernel.h>
16 #include <acpi/acpi.h>
17 #include <linux/ide.h>
18 #include <linux/pci.h>
19 #include <linux/dmi.h>
20
21 #include <acpi/acpi_bus.h>
22 #include <acpi/acnames.h>
23 #include <acpi/acnamesp.h>
24 #include <acpi/acparser.h>
25 #include <acpi/acexcep.h>
26 #include <acpi/acmacros.h>
27 #include <acpi/actypes.h>
28
29 #define REGS_PER_GTF            7
30 struct taskfile_array {
31         u8      tfa[REGS_PER_GTF];      /* regs. 0x1f1 - 0x1f7 */
32 };
33
34 struct GTM_buffer {
35         u32     PIO_speed0;
36         u32     DMA_speed0;
37         u32     PIO_speed1;
38         u32     DMA_speed1;
39         u32     GTM_flags;
40 };
41
42 struct ide_acpi_drive_link {
43         ide_drive_t     *drive;
44         acpi_handle      obj_handle;
45         u8               idbuff[512];
46 };
47
48 struct ide_acpi_hwif_link {
49         ide_hwif_t                      *hwif;
50         acpi_handle                      obj_handle;
51         struct GTM_buffer                gtm;
52         struct ide_acpi_drive_link       master;
53         struct ide_acpi_drive_link       slave;
54 };
55
56 #undef DEBUGGING
57 /* note: adds function name and KERN_DEBUG */
58 #ifdef DEBUGGING
59 #define DEBPRINT(fmt, args...)  \
60                 printk(KERN_DEBUG "%s: " fmt, __FUNCTION__, ## args)
61 #else
62 #define DEBPRINT(fmt, args...)  do {} while (0)
63 #endif  /* DEBUGGING */
64
65 extern int ide_noacpi;
66 extern int ide_noacpitfs;
67 extern int ide_noacpionboot;
68
69 static bool ide_noacpi_psx;
70 static int no_acpi_psx(const struct dmi_system_id *id)
71 {
72         ide_noacpi_psx = true;
73         printk(KERN_NOTICE"%s detected - disable ACPI _PSx.\n", id->ident);
74         return 0;
75 }
76
77 static const struct dmi_system_id ide_acpi_dmi_table[] = {
78         /* Bug 9673. */
79         /* We should check if this is because ACPI NVS isn't save/restored. */
80         {
81                 .callback = no_acpi_psx,
82                 .ident    = "HP nx9005",
83                 .matches  = {
84                         DMI_MATCH(DMI_BIOS_VENDOR, "Phoenix Technologies Ltd."),
85                         DMI_MATCH(DMI_BIOS_VERSION, "KAM1.60")
86                 },
87         },
88
89         { }     /* terminate list */
90 };
91
92 static int ide_acpi_blacklist(void)
93 {
94         static int done;
95         if (done)
96                 return 0;
97         done = 1;
98         dmi_check_system(ide_acpi_dmi_table);
99         return 0;
100 }
101
102 /**
103  * ide_get_dev_handle - finds acpi_handle and PCI device.function
104  * @dev: device to locate
105  * @handle: returned acpi_handle for @dev
106  * @pcidevfn: return PCI device.func for @dev
107  *
108  * Returns the ACPI object handle to the corresponding PCI device.
109  *
110  * Returns 0 on success, <0 on error.
111  */
112 static int ide_get_dev_handle(struct device *dev, acpi_handle *handle,
113                                acpi_integer *pcidevfn)
114 {
115         struct pci_dev *pdev = to_pci_dev(dev);
116         unsigned int bus, devnum, func;
117         acpi_integer addr;
118         acpi_handle dev_handle;
119         struct acpi_buffer buffer = {.length = ACPI_ALLOCATE_BUFFER,
120                                         .pointer = NULL};
121         acpi_status status;
122         struct acpi_device_info *dinfo = NULL;
123         int ret = -ENODEV;
124
125         bus = pdev->bus->number;
126         devnum = PCI_SLOT(pdev->devfn);
127         func = PCI_FUNC(pdev->devfn);
128         /* ACPI _ADR encoding for PCI bus: */
129         addr = (acpi_integer)(devnum << 16 | func);
130
131         DEBPRINT("ENTER: pci %02x:%02x.%01x\n", bus, devnum, func);
132
133         dev_handle = DEVICE_ACPI_HANDLE(dev);
134         if (!dev_handle) {
135                 DEBPRINT("no acpi handle for device\n");
136                 goto err;
137         }
138
139         status = acpi_get_object_info(dev_handle, &buffer);
140         if (ACPI_FAILURE(status)) {
141                 DEBPRINT("get_object_info for device failed\n");
142                 goto err;
143         }
144         dinfo = buffer.pointer;
145         if (dinfo && (dinfo->valid & ACPI_VALID_ADR) &&
146             dinfo->address == addr) {
147                 *pcidevfn = addr;
148                 *handle = dev_handle;
149         } else {
150                 DEBPRINT("get_object_info for device has wrong "
151                         " address: %llu, should be %u\n",
152                         dinfo ? (unsigned long long)dinfo->address : -1ULL,
153                         (unsigned int)addr);
154                 goto err;
155         }
156
157         DEBPRINT("for dev=0x%x.%x, addr=0x%llx, *handle=0x%p\n",
158                  devnum, func, (unsigned long long)addr, *handle);
159         ret = 0;
160 err:
161         kfree(dinfo);
162         return ret;
163 }
164
165 /**
166  * ide_acpi_hwif_get_handle - Get ACPI object handle for a given hwif
167  * @hwif: device to locate
168  *
169  * Retrieves the object handle for a given hwif.
170  *
171  * Returns handle on success, 0 on error.
172  */
173 static acpi_handle ide_acpi_hwif_get_handle(ide_hwif_t *hwif)
174 {
175         struct device           *dev = hwif->gendev.parent;
176         acpi_handle             dev_handle;
177         acpi_integer            pcidevfn;
178         acpi_handle             chan_handle;
179         int                     err;
180
181         DEBPRINT("ENTER: device %s\n", hwif->name);
182
183         if (!dev) {
184                 DEBPRINT("no PCI device for %s\n", hwif->name);
185                 return NULL;
186         }
187
188         err = ide_get_dev_handle(dev, &dev_handle, &pcidevfn);
189         if (err < 0) {
190                 DEBPRINT("ide_get_dev_handle failed (%d)\n", err);
191                 return NULL;
192         }
193
194         /* get child objects of dev_handle == channel objects,
195          * + _their_ children == drive objects */
196         /* channel is hwif->channel */
197         chan_handle = acpi_get_child(dev_handle, hwif->channel);
198         DEBPRINT("chan adr=%d: handle=0x%p\n",
199                  hwif->channel, chan_handle);
200
201         return chan_handle;
202 }
203
204 /**
205  * ide_acpi_drive_get_handle - Get ACPI object handle for a given drive
206  * @drive: device to locate
207  *
208  * Retrieves the object handle of a given drive. According to the ACPI
209  * spec the drive is a child of the hwif.
210  *
211  * Returns handle on success, 0 on error.
212  */
213 static acpi_handle ide_acpi_drive_get_handle(ide_drive_t *drive)
214 {
215         ide_hwif_t      *hwif = HWIF(drive);
216         int              port;
217         acpi_handle      drive_handle;
218
219         if (!hwif->acpidata)
220                 return NULL;
221
222         if (!hwif->acpidata->obj_handle)
223                 return NULL;
224
225         port = hwif->channel ? drive->dn - 2: drive->dn;
226
227         DEBPRINT("ENTER: %s at channel#: %d port#: %d\n",
228                  drive->name, hwif->channel, port);
229
230
231         /* TBD: could also check ACPI object VALID bits */
232         drive_handle = acpi_get_child(hwif->acpidata->obj_handle, port);
233         DEBPRINT("drive %s handle 0x%p\n", drive->name, drive_handle);
234
235         return drive_handle;
236 }
237
238 /**
239  * do_drive_get_GTF - get the drive bootup default taskfile settings
240  * @drive: the drive for which the taskfile settings should be retrieved
241  * @gtf_length: number of bytes of _GTF data returned at @gtf_address
242  * @gtf_address: buffer containing _GTF taskfile arrays
243  *
244  * The _GTF method has no input parameters.
245  * It returns a variable number of register set values (registers
246  * hex 1F1..1F7, taskfiles).
247  * The <variable number> is not known in advance, so have ACPI-CA
248  * allocate the buffer as needed and return it, then free it later.
249  *
250  * The returned @gtf_length and @gtf_address are only valid if the
251  * function return value is 0.
252  */
253 static int do_drive_get_GTF(ide_drive_t *drive,
254                      unsigned int *gtf_length, unsigned long *gtf_address,
255                      unsigned long *obj_loc)
256 {
257         acpi_status                     status;
258         struct acpi_buffer              output;
259         union acpi_object               *out_obj;
260         ide_hwif_t                      *hwif = HWIF(drive);
261         struct device                   *dev = hwif->gendev.parent;
262         int                             err = -ENODEV;
263         int                             port;
264
265         *gtf_length = 0;
266         *gtf_address = 0UL;
267         *obj_loc = 0UL;
268
269         if (ide_noacpi)
270                 return 0;
271
272         if (!dev) {
273                 DEBPRINT("no PCI device for %s\n", hwif->name);
274                 goto out;
275         }
276
277         if (!hwif->acpidata) {
278                 DEBPRINT("no ACPI data for %s\n", hwif->name);
279                 goto out;
280         }
281
282         port = hwif->channel ? drive->dn - 2: drive->dn;
283
284         if (!drive->acpidata) {
285                 if (port == 0) {
286                         drive->acpidata = &hwif->acpidata->master;
287                         hwif->acpidata->master.drive = drive;
288                 } else {
289                         drive->acpidata = &hwif->acpidata->slave;
290                         hwif->acpidata->slave.drive = drive;
291                 }
292         }
293
294         DEBPRINT("ENTER: %s at %s, port#: %d, hard_port#: %d\n",
295                  hwif->name, dev->bus_id, port, hwif->channel);
296
297         if (!drive->present) {
298                 DEBPRINT("%s drive %d:%d not present\n",
299                          hwif->name, hwif->channel, port);
300                 goto out;
301         }
302
303         /* Get this drive's _ADR info. if not already known. */
304         if (!drive->acpidata->obj_handle) {
305                 drive->acpidata->obj_handle = ide_acpi_drive_get_handle(drive);
306                 if (!drive->acpidata->obj_handle) {
307                         DEBPRINT("No ACPI object found for %s\n",
308                                  drive->name);
309                         goto out;
310                 }
311         }
312
313         /* Setting up output buffer */
314         output.length = ACPI_ALLOCATE_BUFFER;
315         output.pointer = NULL;  /* ACPI-CA sets this; save/free it later */
316
317         /* _GTF has no input parameters */
318         err = -EIO;
319         status = acpi_evaluate_object(drive->acpidata->obj_handle, "_GTF",
320                                       NULL, &output);
321         if (ACPI_FAILURE(status)) {
322                 printk(KERN_DEBUG
323                        "%s: Run _GTF error: status = 0x%x\n",
324                        __FUNCTION__, status);
325                 goto out;
326         }
327
328         if (!output.length || !output.pointer) {
329                 DEBPRINT("Run _GTF: "
330                        "length or ptr is NULL (0x%llx, 0x%p)\n",
331                        (unsigned long long)output.length,
332                        output.pointer);
333                 goto out;
334         }
335
336         out_obj = output.pointer;
337         if (out_obj->type != ACPI_TYPE_BUFFER) {
338                 DEBPRINT("Run _GTF: error: "
339                        "expected object type of ACPI_TYPE_BUFFER, "
340                        "got 0x%x\n", out_obj->type);
341                 err = -ENOENT;
342                 kfree(output.pointer);
343                 goto out;
344         }
345
346         if (!out_obj->buffer.length || !out_obj->buffer.pointer ||
347             out_obj->buffer.length % REGS_PER_GTF) {
348                 printk(KERN_ERR
349                        "%s: unexpected GTF length (%d) or addr (0x%p)\n",
350                        __FUNCTION__, out_obj->buffer.length,
351                        out_obj->buffer.pointer);
352                 err = -ENOENT;
353                 kfree(output.pointer);
354                 goto out;
355         }
356
357         *gtf_length = out_obj->buffer.length;
358         *gtf_address = (unsigned long)out_obj->buffer.pointer;
359         *obj_loc = (unsigned long)out_obj;
360         DEBPRINT("returning gtf_length=%d, gtf_address=0x%lx, obj_loc=0x%lx\n",
361                  *gtf_length, *gtf_address, *obj_loc);
362         err = 0;
363 out:
364         return err;
365 }
366
367 /**
368  * taskfile_load_raw - send taskfile registers to drive
369  * @drive: drive to which output is sent
370  * @gtf: raw ATA taskfile register set (0x1f1 - 0x1f7)
371  *
372  * Outputs IDE taskfile to the drive.
373  */
374 static int taskfile_load_raw(ide_drive_t *drive,
375                               const struct taskfile_array *gtf)
376 {
377         ide_task_t args;
378         int err = 0;
379
380         DEBPRINT("(0x1f1-1f7): hex: "
381                "%02x %02x %02x %02x %02x %02x %02x\n",
382                gtf->tfa[0], gtf->tfa[1], gtf->tfa[2],
383                gtf->tfa[3], gtf->tfa[4], gtf->tfa[5], gtf->tfa[6]);
384
385         memset(&args, 0, sizeof(ide_task_t));
386         args.command_type = IDE_DRIVE_TASK_NO_DATA;
387         args.data_phase   = TASKFILE_NO_DATA;
388         args.handler      = &task_no_data_intr;
389
390         /* convert gtf to IDE Taskfile */
391         args.tfRegister[1] = gtf->tfa[0];       /* 0x1f1 */
392         args.tfRegister[2] = gtf->tfa[1];       /* 0x1f2 */
393         args.tfRegister[3] = gtf->tfa[2];       /* 0x1f3 */
394         args.tfRegister[4] = gtf->tfa[3];       /* 0x1f4 */
395         args.tfRegister[5] = gtf->tfa[4];       /* 0x1f5 */
396         args.tfRegister[6] = gtf->tfa[5];       /* 0x1f6 */
397         args.tfRegister[7] = gtf->tfa[6];       /* 0x1f7 */
398
399         if (ide_noacpitfs) {
400                 DEBPRINT("_GTF execution disabled\n");
401                 return err;
402         }
403
404         err = ide_raw_taskfile(drive, &args, NULL);
405         if (err)
406                 printk(KERN_ERR "%s: ide_raw_taskfile failed: %u\n",
407                        __FUNCTION__, err);
408
409         return err;
410 }
411
412 /**
413  * do_drive_set_taskfiles - write the drive taskfile settings from _GTF
414  * @drive: the drive to which the taskfile command should be sent
415  * @gtf_length: total number of bytes of _GTF taskfiles
416  * @gtf_address: location of _GTF taskfile arrays
417  *
418  * Write {gtf_address, length gtf_length} in groups of
419  * REGS_PER_GTF bytes.
420  */
421 static int do_drive_set_taskfiles(ide_drive_t *drive,
422                                   unsigned int gtf_length,
423                                   unsigned long gtf_address)
424 {
425         int                     rc = -ENODEV, err;
426         int                     gtf_count = gtf_length / REGS_PER_GTF;
427         int                     ix;
428         struct taskfile_array   *gtf;
429
430         if (ide_noacpi)
431                 return 0;
432
433         DEBPRINT("ENTER: %s, hard_port#: %d\n", drive->name, drive->dn);
434
435         if (!drive->present)
436                 goto out;
437         if (!gtf_count)         /* shouldn't be here */
438                 goto out;
439
440         DEBPRINT("total GTF bytes=%u (0x%x), gtf_count=%d, addr=0x%lx\n",
441                  gtf_length, gtf_length, gtf_count, gtf_address);
442
443         if (gtf_length % REGS_PER_GTF) {
444                 printk(KERN_ERR "%s: unexpected GTF length (%d)\n",
445                        __FUNCTION__, gtf_length);
446                 goto out;
447         }
448
449         rc = 0;
450         for (ix = 0; ix < gtf_count; ix++) {
451                 gtf = (struct taskfile_array *)
452                         (gtf_address + ix * REGS_PER_GTF);
453
454                 /* send all TaskFile registers (0x1f1-0x1f7) *in*that*order* */
455                 err = taskfile_load_raw(drive, gtf);
456                 if (err)
457                         rc = err;
458         }
459
460 out:
461         return rc;
462 }
463
464 /**
465  * ide_acpi_exec_tfs - get then write drive taskfile settings
466  * @drive: the drive for which the taskfile settings should be
467  *         written.
468  *
469  * According to the ACPI spec this should be called after _STM
470  * has been evaluated for the interface. Some ACPI vendors interpret
471  * that as a hard requirement and modify the taskfile according
472  * to the Identify Drive information passed down with _STM.
473  * So one should really make sure to call this only after _STM has
474  * been executed.
475  */
476 int ide_acpi_exec_tfs(ide_drive_t *drive)
477 {
478         int             ret;
479         unsigned int    gtf_length;
480         unsigned long   gtf_address;
481         unsigned long   obj_loc;
482
483         if (ide_noacpi)
484                 return 0;
485
486         DEBPRINT("call get_GTF, drive=%s port=%d\n", drive->name, drive->dn);
487
488         ret = do_drive_get_GTF(drive, &gtf_length, &gtf_address, &obj_loc);
489         if (ret < 0) {
490                 DEBPRINT("get_GTF error (%d)\n", ret);
491                 return ret;
492         }
493
494         DEBPRINT("call set_taskfiles, drive=%s\n", drive->name);
495
496         ret = do_drive_set_taskfiles(drive, gtf_length, gtf_address);
497         kfree((void *)obj_loc);
498         if (ret < 0) {
499                 DEBPRINT("set_taskfiles error (%d)\n", ret);
500         }
501
502         DEBPRINT("ret=%d\n", ret);
503
504         return ret;
505 }
506 EXPORT_SYMBOL_GPL(ide_acpi_exec_tfs);
507
508 /**
509  * ide_acpi_get_timing - get the channel (controller) timings
510  * @hwif: target IDE interface (channel)
511  *
512  * This function executes the _GTM ACPI method for the target channel.
513  *
514  */
515 void ide_acpi_get_timing(ide_hwif_t *hwif)
516 {
517         acpi_status             status;
518         struct acpi_buffer      output;
519         union acpi_object       *out_obj;
520
521         if (ide_noacpi)
522                 return;
523
524         DEBPRINT("ENTER:\n");
525
526         if (!hwif->acpidata) {
527                 DEBPRINT("no ACPI data for %s\n", hwif->name);
528                 return;
529         }
530
531         /* Setting up output buffer for _GTM */
532         output.length = ACPI_ALLOCATE_BUFFER;
533         output.pointer = NULL;  /* ACPI-CA sets this; save/free it later */
534
535         /* _GTM has no input parameters */
536         status = acpi_evaluate_object(hwif->acpidata->obj_handle, "_GTM",
537                                       NULL, &output);
538
539         DEBPRINT("_GTM status: %d, outptr: 0x%p, outlen: 0x%llx\n",
540                  status, output.pointer,
541                  (unsigned long long)output.length);
542
543         if (ACPI_FAILURE(status)) {
544                 DEBPRINT("Run _GTM error: status = 0x%x\n", status);
545                 return;
546         }
547
548         if (!output.length || !output.pointer) {
549                 DEBPRINT("Run _GTM: length or ptr is NULL (0x%llx, 0x%p)\n",
550                        (unsigned long long)output.length,
551                        output.pointer);
552                 kfree(output.pointer);
553                 return;
554         }
555
556         out_obj = output.pointer;
557         if (out_obj->type != ACPI_TYPE_BUFFER) {
558                 kfree(output.pointer);
559                 DEBPRINT("Run _GTM: error: "
560                        "expected object type of ACPI_TYPE_BUFFER, "
561                        "got 0x%x\n", out_obj->type);
562                 return;
563         }
564
565         if (!out_obj->buffer.length || !out_obj->buffer.pointer ||
566             out_obj->buffer.length != sizeof(struct GTM_buffer)) {
567                 kfree(output.pointer);
568                 printk(KERN_ERR
569                         "%s: unexpected _GTM length (0x%x)[should be 0x%zx] or "
570                         "addr (0x%p)\n",
571                         __FUNCTION__, out_obj->buffer.length,
572                         sizeof(struct GTM_buffer), out_obj->buffer.pointer);
573                 return;
574         }
575
576         memcpy(&hwif->acpidata->gtm, out_obj->buffer.pointer,
577                sizeof(struct GTM_buffer));
578
579         DEBPRINT("_GTM info: ptr: 0x%p, len: 0x%x, exp.len: 0x%Zx\n",
580                  out_obj->buffer.pointer, out_obj->buffer.length,
581                  sizeof(struct GTM_buffer));
582
583         DEBPRINT("_GTM fields: 0x%x, 0x%x, 0x%x, 0x%x, 0x%x\n",
584                  hwif->acpidata->gtm.PIO_speed0,
585                  hwif->acpidata->gtm.DMA_speed0,
586                  hwif->acpidata->gtm.PIO_speed1,
587                  hwif->acpidata->gtm.DMA_speed1,
588                  hwif->acpidata->gtm.GTM_flags);
589
590         kfree(output.pointer);
591 }
592 EXPORT_SYMBOL_GPL(ide_acpi_get_timing);
593
594 /**
595  * ide_acpi_push_timing - set the channel (controller) timings
596  * @hwif: target IDE interface (channel)
597  *
598  * This function executes the _STM ACPI method for the target channel.
599  *
600  * _STM requires Identify Drive data, which has to passed as an argument.
601  * Unfortunately hd_driveid is a mangled version which we can't readily
602  * use; hence we'll get the information afresh.
603  */
604 void ide_acpi_push_timing(ide_hwif_t *hwif)
605 {
606         acpi_status             status;
607         struct acpi_object_list input;
608         union acpi_object       in_params[3];
609         struct ide_acpi_drive_link      *master = &hwif->acpidata->master;
610         struct ide_acpi_drive_link      *slave = &hwif->acpidata->slave;
611
612         if (ide_noacpi)
613                 return;
614
615         DEBPRINT("ENTER:\n");
616
617         if (!hwif->acpidata) {
618                 DEBPRINT("no ACPI data for %s\n", hwif->name);
619                 return;
620         }
621
622         /* Give the GTM buffer + drive Identify data to the channel via the
623          * _STM method: */
624         /* setup input parameters buffer for _STM */
625         input.count = 3;
626         input.pointer = in_params;
627         in_params[0].type = ACPI_TYPE_BUFFER;
628         in_params[0].buffer.length = sizeof(struct GTM_buffer);
629         in_params[0].buffer.pointer = (u8 *)&hwif->acpidata->gtm;
630         in_params[1].type = ACPI_TYPE_BUFFER;
631         in_params[1].buffer.length = sizeof(struct hd_driveid);
632         in_params[1].buffer.pointer = (u8 *)&master->idbuff;
633         in_params[2].type = ACPI_TYPE_BUFFER;
634         in_params[2].buffer.length = sizeof(struct hd_driveid);
635         in_params[2].buffer.pointer = (u8 *)&slave->idbuff;
636         /* Output buffer: _STM has no output */
637
638         status = acpi_evaluate_object(hwif->acpidata->obj_handle, "_STM",
639                                       &input, NULL);
640
641         if (ACPI_FAILURE(status)) {
642                 DEBPRINT("Run _STM error: status = 0x%x\n", status);
643         }
644         DEBPRINT("_STM status: %d\n", status);
645 }
646 EXPORT_SYMBOL_GPL(ide_acpi_push_timing);
647
648 /**
649  * ide_acpi_set_state - set the channel power state
650  * @hwif: target IDE interface
651  * @on: state, on/off
652  *
653  * This function executes the _PS0/_PS3 ACPI method to set the power state.
654  * ACPI spec requires _PS0 when IDE power on and _PS3 when power off
655  */
656 void ide_acpi_set_state(ide_hwif_t *hwif, int on)
657 {
658         int unit;
659
660         if (ide_noacpi || ide_noacpi_psx)
661                 return;
662
663         DEBPRINT("ENTER:\n");
664
665         if (!hwif->acpidata) {
666                 DEBPRINT("no ACPI data for %s\n", hwif->name);
667                 return;
668         }
669         /* channel first and then drives for power on and verse versa for power off */
670         if (on)
671                 acpi_bus_set_power(hwif->acpidata->obj_handle, ACPI_STATE_D0);
672         for (unit = 0; unit < MAX_DRIVES; ++unit) {
673                 ide_drive_t *drive = &hwif->drives[unit];
674
675                 if (!drive->acpidata->obj_handle)
676                         drive->acpidata->obj_handle = ide_acpi_drive_get_handle(drive);
677
678                 if (drive->acpidata->obj_handle && drive->present) {
679                         acpi_bus_set_power(drive->acpidata->obj_handle,
680                                 on? ACPI_STATE_D0: ACPI_STATE_D3);
681                 }
682         }
683         if (!on)
684                 acpi_bus_set_power(hwif->acpidata->obj_handle, ACPI_STATE_D3);
685 }
686
687 /**
688  * ide_acpi_init - initialize the ACPI link for an IDE interface
689  * @hwif: target IDE interface (channel)
690  *
691  * The ACPI spec is not quite clear when the drive identify buffer
692  * should be obtained. Calling IDENTIFY DEVICE during shutdown
693  * is not the best of ideas as the drive might already being put to
694  * sleep. And obviously we can't call it during resume.
695  * So we get the information during startup; but this means that
696  * any changes during run-time will be lost after resume.
697  */
698 void ide_acpi_init(ide_hwif_t *hwif)
699 {
700         int unit;
701         int                     err;
702         struct ide_acpi_drive_link      *master;
703         struct ide_acpi_drive_link      *slave;
704
705         ide_acpi_blacklist();
706
707         hwif->acpidata = kzalloc(sizeof(struct ide_acpi_hwif_link), GFP_KERNEL);
708         if (!hwif->acpidata)
709                 return;
710
711         hwif->acpidata->obj_handle = ide_acpi_hwif_get_handle(hwif);
712         if (!hwif->acpidata->obj_handle) {
713                 DEBPRINT("no ACPI object for %s found\n", hwif->name);
714                 kfree(hwif->acpidata);
715                 hwif->acpidata = NULL;
716                 return;
717         }
718
719         /*
720          * The ACPI spec mandates that we send information
721          * for both drives, regardless whether they are connected
722          * or not.
723          */
724         hwif->acpidata->master.drive = &hwif->drives[0];
725         hwif->drives[0].acpidata = &hwif->acpidata->master;
726         master = &hwif->acpidata->master;
727
728         hwif->acpidata->slave.drive = &hwif->drives[1];
729         hwif->drives[1].acpidata = &hwif->acpidata->slave;
730         slave = &hwif->acpidata->slave;
731
732
733         /*
734          * Send IDENTIFY for each drive
735          */
736         if (master->drive->present) {
737                 err = taskfile_lib_get_identify(master->drive, master->idbuff);
738                 if (err) {
739                         DEBPRINT("identify device %s failed (%d)\n",
740                                  master->drive->name, err);
741                 }
742         }
743
744         if (slave->drive->present) {
745                 err = taskfile_lib_get_identify(slave->drive, slave->idbuff);
746                 if (err) {
747                         DEBPRINT("identify device %s failed (%d)\n",
748                                  slave->drive->name, err);
749                 }
750         }
751
752         if (ide_noacpionboot) {
753                 DEBPRINT("ACPI methods disabled on boot\n");
754                 return;
755         }
756
757         /* ACPI _PS0 before _STM */
758         ide_acpi_set_state(hwif, 1);
759         /*
760          * ACPI requires us to call _STM on startup
761          */
762         ide_acpi_get_timing(hwif);
763         ide_acpi_push_timing(hwif);
764
765         for (unit = 0; unit < MAX_DRIVES; ++unit) {
766                 ide_drive_t *drive = &hwif->drives[unit];
767
768                 if (drive->present) {
769                         /* Execute ACPI startup code */
770                         ide_acpi_exec_tfs(drive);
771                 }
772         }
773 }
774 EXPORT_SYMBOL_GPL(ide_acpi_init);