sound/pci/asihpi/hpioctl.c

   1 /*******************************************************************************
   2     AudioScience HPI driver
   3     Common Linux HPI ioctl and module probe/remove functions
   4
   5     Copyright (C) 1997-2014  AudioScience Inc. <support@audioscience.com>
   6
   7     This program is free software; you can redistribute it and/or modify
   8     it under the terms of version 2 of the GNU General Public License as
   9     published by the Free Software Foundation;
  10
  11     This program is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15
  16 *******************************************************************************/
  17 #define SOURCEFILE_NAME "hpioctl.c"
  18
  19 #include "hpi_internal.h"
  20 #include "hpi_version.h"
  21 #include "hpimsginit.h"
  22 #include "hpidebug.h"
  23 #include "hpimsgx.h"
  24 #include "hpioctl.h"
  25 #include "hpicmn.h"
  26
  27 #include <linux/fs.h>
  28 #include <linux/interrupt.h>
  29 #include <linux/slab.h>
  30 #include <linux/moduleparam.h>
  31 #include <linux/uaccess.h>
  32 #include <linux/pci.h>
  33 #include <linux/stringify.h>
  34 #include <linux/module.h>
  35 #include <linux/vmalloc.h>
  36 #include <linux/nospec.h>
  37
  38 #ifdef MODULE_FIRMWARE
  39 MODULE_FIRMWARE("asihpi/dsp5000.bin");
  40 MODULE_FIRMWARE("asihpi/dsp6200.bin");
  41 MODULE_FIRMWARE("asihpi/dsp6205.bin");
  42 MODULE_FIRMWARE("asihpi/dsp6400.bin");
  43 MODULE_FIRMWARE("asihpi/dsp6600.bin");
  44 MODULE_FIRMWARE("asihpi/dsp8700.bin");
  45 MODULE_FIRMWARE("asihpi/dsp8900.bin");
  46 #endif
  47
  48 static int prealloc_stream_buf;
  49 module_param(prealloc_stream_buf, int, S_IRUGO);
  50 MODULE_PARM_DESC(prealloc_stream_buf,
  51         "Preallocate size for per-adapter stream buffer");
  52
  53 /* Allow the debug level to be changed after module load.
  54  E.g.   echo 2 > /sys/module/asihpi/parameters/hpiDebugLevel
  55 */
  56 module_param(hpi_debug_level, int, S_IRUGO | S_IWUSR);
  57 MODULE_PARM_DESC(hpi_debug_level, "debug verbosity 0..5");
  58
  59 /* List of adapters found */
  60 static struct hpi_adapter adapters[HPI_MAX_ADAPTERS];
  61
  62 /* Wrapper function to HPI_Message to enable dumping of the
  63    message and response types.
  64 */
  65 static void hpi_send_recv_f(struct hpi_message *phm, struct hpi_response *phr,
  66         struct file *file)
  67 {
  68         if ((phm->adapter_index >= HPI_MAX_ADAPTERS)
  69                 && (phm->object != HPI_OBJ_SUBSYSTEM))
  70                 phr->error = HPI_ERROR_INVALID_OBJ_INDEX;
  71         else
  72                 hpi_send_recv_ex(phm, phr, file);
  73 }
  74
  75 /* This is called from hpifunc.c functions, called by ALSA
  76  * (or other kernel process) In this case there is no file descriptor
  77  * available for the message cache code
  78  */
  79 void hpi_send_recv(struct hpi_message *phm, struct hpi_response *phr)
  80 {
  81         hpi_send_recv_f(phm, phr, HOWNER_KERNEL);
  82 }
  83
  84 EXPORT_SYMBOL(hpi_send_recv);
  85 /* for radio-asihpi */
  86
  87 int asihpi_hpi_release(struct file *file)
  88 {
  89         struct hpi_message hm;
  90         struct hpi_response hr;
  91
  92 /* HPI_DEBUG_LOG(INFO,"hpi_release file %p, pid %d\n", file, current->pid); */
  93         /* close the subsystem just in case the application forgot to. */
  94         hpi_init_message_response(&hm, &hr, HPI_OBJ_SUBSYSTEM,
  95                 HPI_SUBSYS_CLOSE);
  96         hpi_send_recv_ex(&hm, &hr, file);
  97         return 0;
  98 }
  99
 100 long asihpi_hpi_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 101 {
 102         struct hpi_ioctl_linux __user *phpi_ioctl_data;
 103         void __user *puhm;
 104         void __user *puhr;
 105         union hpi_message_buffer_v1 *hm;
 106         union hpi_response_buffer_v1 *hr;
 107         u16 msg_size;
 108         u16 res_max_size;
 109         u32 uncopied_bytes;
 110         int err = 0;
 111
 112         if (cmd != HPI_IOCTL_LINUX)
 113                 return -EINVAL;
 114
 115         hm = kmalloc(sizeof(*hm), GFP_KERNEL);
 116         hr = kzalloc(sizeof(*hr), GFP_KERNEL);
 117         if (!hm || !hr) {
 118                 err = -ENOMEM;
 119                 goto out;
 120         }
 121
 122         phpi_ioctl_data = (struct hpi_ioctl_linux __user *)arg;
 123
 124         /* Read the message and response pointers from user space.  */
 125         if (get_user(puhm, &phpi_ioctl_data->phm)
 126                 || get_user(puhr, &phpi_ioctl_data->phr)) {
 127                 err = -EFAULT;
 128                 goto out;
 129         }
 130
 131         /* Now read the message size and data from user space.  */
 132         if (get_user(msg_size, (u16 __user *)puhm)) {
 133                 err = -EFAULT;
 134                 goto out;
 135         }
 136         if (msg_size > sizeof(*hm))
 137                 msg_size = sizeof(*hm);
 138
 139         /* printk(KERN_INFO "message size %d\n", hm->h.wSize); */
 140
 141         uncopied_bytes = copy_from_user(hm, puhm, msg_size);
 142         if (uncopied_bytes) {
 143                 HPI_DEBUG_LOG(ERROR, "uncopied bytes %d\n", uncopied_bytes);
 144                 err = -EFAULT;
 145                 goto out;
 146         }
 147
 148         /* Override h.size in case it is changed between two userspace fetches */
 149         hm->h.size = msg_size;
 150
 151         if (get_user(res_max_size, (u16 __user *)puhr)) {
 152                 err = -EFAULT;
 153                 goto out;
 154         }
 155         /* printk(KERN_INFO "user response size %d\n", res_max_size); */
 156         if (res_max_size < sizeof(struct hpi_response_header)) {
 157                 HPI_DEBUG_LOG(WARNING, "small res size %d\n", res_max_size);
 158                 err = -EFAULT;
 159                 goto out;
 160         }
 161
 162         res_max_size = min_t(size_t, res_max_size, sizeof(*hr));
 163
 164         switch (hm->h.function) {
 165         case HPI_SUBSYS_CREATE_ADAPTER:
 166         case HPI_ADAPTER_DELETE:
 167                 /* Application must not use these functions! */
 168                 hr->h.size = sizeof(hr->h);
 169                 hr->h.error = HPI_ERROR_INVALID_OPERATION;
 170                 hr->h.function = hm->h.function;
 171                 uncopied_bytes = copy_to_user(puhr, hr, hr->h.size);
 172                 if (uncopied_bytes)
 173                         err = -EFAULT;
 174                 else
 175                         err = 0;
 176                 goto out;
 177         }
 178
 179         hr->h.size = res_max_size;
 180         if (hm->h.object == HPI_OBJ_SUBSYSTEM) {
 181                 hpi_send_recv_f(&hm->m0, &hr->r0, file);
 182         } else {
 183                 u16 __user *ptr = NULL;
 184                 u32 size = 0;
 185                 /* -1=no data 0=read from user mem, 1=write to user mem */
 186                 int wrflag = -1;
 187                 struct hpi_adapter *pa = NULL;
 188
 189                 if (hm->h.adapter_index < ARRAY_SIZE(adapters))
 190                         pa = &adapters[array_index_nospec(hm->h.adapter_index,
 191                                                           ARRAY_SIZE(adapters))];
 192
 193                 if (!pa || !pa->adapter || !pa->adapter->type) {
 194                         hpi_init_response(&hr->r0, hm->h.object,
 195                                 hm->h.function, HPI_ERROR_BAD_ADAPTER_NUMBER);
 196
 197                         uncopied_bytes =
 198                                 copy_to_user(puhr, hr, sizeof(hr->h));
 199                         if (uncopied_bytes)
 200                                 err = -EFAULT;
 201                         else
 202                                 err = 0;
 203                         goto out;
 204                 }
 205
 206                 if (mutex_lock_interruptible(&pa->mutex)) {
 207                         err = -EINTR;
 208                         goto out;
 209                 }
 210
 211                 /* Dig out any pointers embedded in the message.  */
 212                 switch (hm->h.function) {
 213                 case HPI_OSTREAM_WRITE:
 214                 case HPI_ISTREAM_READ:{
 215                                 /* Yes, sparse, this is correct. */
 216                                 ptr = (u16 __user *)hm->m0.u.d.u.data.pb_data;
 217                                 size = hm->m0.u.d.u.data.data_size;
 218
 219                                 /* Allocate buffer according to application request.
 220                                    ?Is it better to alloc/free for the duration
 221                                    of the transaction?
 222                                  */
 223                                 if (pa->buffer_size < size) {
 224                                         HPI_DEBUG_LOG(DEBUG,
 225                                                 "Realloc adapter %d stream "
 226                                                 "buffer from %zd to %d\n",
 227                                                 hm->h.adapter_index,
 228                                                 pa->buffer_size, size);
 229                                         if (pa->p_buffer) {
 230                                                 pa->buffer_size = 0;
 231                                                 vfree(pa->p_buffer);
 232                                         }
 233                                         pa->p_buffer = vmalloc(size);
 234                                         if (pa->p_buffer)
 235                                                 pa->buffer_size = size;
 236                                         else {
 237                                                 HPI_DEBUG_LOG(ERROR,
 238                                                         "HPI could not allocate "
 239                                                         "stream buffer size %d\n",
 240                                                         size);
 241
 242                                                 mutex_unlock(&pa->mutex);
 243                                                 err = -EINVAL;
 244                                                 goto out;
 245                                         }
 246                                 }
 247
 248                                 hm->m0.u.d.u.data.pb_data = pa->p_buffer;
 249                                 if (hm->h.function == HPI_ISTREAM_READ)
 250                                         /* from card, WRITE to user mem */
 251                                         wrflag = 1;
 252                                 else
 253                                         wrflag = 0;
 254                                 break;
 255                         }
 256
 257                 default:
 258                         size = 0;
 259                         break;
 260                 }
 261
 262                 if (size && (wrflag == 0)) {
 263                         uncopied_bytes =
 264                                 copy_from_user(pa->p_buffer, ptr, size);
 265                         if (uncopied_bytes)
 266                                 HPI_DEBUG_LOG(WARNING,
 267                                         "Missed %d of %d "
 268                                         "bytes from user\n", uncopied_bytes,
 269                                         size);
 270                 }
 271
 272                 hpi_send_recv_f(&hm->m0, &hr->r0, file);
 273
 274                 if (size && (wrflag == 1)) {
 275                         uncopied_bytes =
 276                                 copy_to_user(ptr, pa->p_buffer, size);
 277                         if (uncopied_bytes)
 278                                 HPI_DEBUG_LOG(WARNING,
 279                                         "Missed %d of %d " "bytes to user\n",
 280                                         uncopied_bytes, size);
 281                 }
 282
 283                 mutex_unlock(&pa->mutex);
 284         }
 285
 286         /* on return response size must be set */
 287         /*printk(KERN_INFO "response size %d\n", hr->h.wSize); */
 288
 289         if (!hr->h.size) {
 290                 HPI_DEBUG_LOG(ERROR, "response zero size\n");
 291                 err = -EFAULT;
 292                 goto out;
 293         }
 294
 295         if (hr->h.size > res_max_size) {
 296                 HPI_DEBUG_LOG(ERROR, "response too big %d %d\n", hr->h.size,
 297                         res_max_size);
 298                 hr->h.error = HPI_ERROR_RESPONSE_BUFFER_TOO_SMALL;
 299                 hr->h.specific_error = hr->h.size;
 300                 hr->h.size = sizeof(hr->h);
 301         }
 302
 303         uncopied_bytes = copy_to_user(puhr, hr, hr->h.size);
 304         if (uncopied_bytes) {
 305                 HPI_DEBUG_LOG(ERROR, "uncopied bytes %d\n", uncopied_bytes);
 306                 err = -EFAULT;
 307                 goto out;
 308         }
 309
 310 out:
 311         kfree(hm);
 312         kfree(hr);
 313         return err;
 314 }
 315
 316 static int asihpi_irq_count;
 317
 318 static irqreturn_t asihpi_isr(int irq, void *dev_id)
 319 {
 320         struct hpi_adapter *a = dev_id;
 321         int handled;
 322
 323         if (!a->adapter->irq_query_and_clear) {
 324                 pr_err("asihpi_isr ASI%04X:%d no handler\n", a->adapter->type,
 325                         a->adapter->index);
 326                 return IRQ_NONE;
 327         }
 328
 329         handled = a->adapter->irq_query_and_clear(a->adapter, 0);
 330
 331         if (!handled)
 332                 return IRQ_NONE;
 333
 334         asihpi_irq_count++;
 335         /* printk(KERN_INFO "asihpi_isr %d ASI%04X:%d irq handled\n",
 336            asihpi_irq_count, a->adapter->type, a->adapter->index); */
 337
 338         if (a->interrupt_callback)
 339                 a->interrupt_callback(a);
 340
 341         return IRQ_HANDLED;
 342 }
 343
 344 int asihpi_adapter_probe(struct pci_dev *pci_dev,
 345                          const struct pci_device_id *pci_id)
 346 {
 347         int idx, nm, low_latency_mode = 0, irq_supported = 0;
 348         int adapter_index;
 349         unsigned int memlen;
 350         struct hpi_message hm;
 351         struct hpi_response hr;
 352         struct hpi_adapter adapter;
 353         struct hpi_pci pci;
 354
 355         memset(&adapter, 0, sizeof(adapter));
 356
 357         dev_printk(KERN_DEBUG, &pci_dev->dev,
 358                 "probe %04x:%04x,%04x:%04x,%04x\n", pci_dev->vendor,
 359                 pci_dev->device, pci_dev->subsystem_vendor,
 360                 pci_dev->subsystem_device, pci_dev->devfn);
 361
 362         if (pci_enable_device(pci_dev) < 0) {
 363                 dev_err(&pci_dev->dev,
 364                         "pci_enable_device failed, disabling device\n");
 365                 return -EIO;
 366         }
 367
 368         pci_set_master(pci_dev);        /* also sets latency timer if < 16 */
 369
 370         hpi_init_message_response(&hm, &hr, HPI_OBJ_SUBSYSTEM,
 371                 HPI_SUBSYS_CREATE_ADAPTER);
 372         hpi_init_response(&hr, HPI_OBJ_SUBSYSTEM, HPI_SUBSYS_CREATE_ADAPTER,
 373                 HPI_ERROR_PROCESSING_MESSAGE);
 374
 375         hm.adapter_index = HPI_ADAPTER_INDEX_INVALID;
 376
 377         nm = HPI_MAX_ADAPTER_MEM_SPACES;
 378
 379         for (idx = 0; idx < nm; idx++) {
 380                 HPI_DEBUG_LOG(INFO, "resource %d %pR\n", idx,
 381                         &pci_dev->resource[idx]);
 382
 383                 if (pci_resource_flags(pci_dev, idx) & IORESOURCE_MEM) {
 384                         memlen = pci_resource_len(pci_dev, idx);
 385                         pci.ap_mem_base[idx] =
 386                                 ioremap(pci_resource_start(pci_dev, idx),
 387                                 memlen);
 388                         if (!pci.ap_mem_base[idx]) {
 389                                 HPI_DEBUG_LOG(ERROR,
 390                                         "ioremap failed, aborting\n");
 391                                 /* unmap previously mapped pci mem space */
 392                                 goto err;
 393                         }
 394                 }
 395         }
 396
 397         pci.pci_dev = pci_dev;
 398         hm.u.s.resource.bus_type = HPI_BUS_PCI;
 399         hm.u.s.resource.r.pci = &pci;
 400
 401         /* call CreateAdapterObject on the relevant hpi module */
 402         hpi_send_recv_ex(&hm, &hr, HOWNER_KERNEL);
 403         if (hr.error)
 404                 goto err;
 405
 406         adapter_index = hr.u.s.adapter_index;
 407         adapter.adapter = hpi_find_adapter(adapter_index);
 408
 409         if (prealloc_stream_buf) {
 410                 adapter.p_buffer = vmalloc(prealloc_stream_buf);
 411                 if (!adapter.p_buffer) {
 412                         HPI_DEBUG_LOG(ERROR,
 413                                 "HPI could not allocate "
 414                                 "kernel buffer size %d\n",
 415                                 prealloc_stream_buf);
 416                         goto err;
 417                 }
 418         }
 419
 420         hpi_init_message_response(&hm, &hr, HPI_OBJ_ADAPTER,
 421                 HPI_ADAPTER_OPEN);
 422         hm.adapter_index = adapter.adapter->index;
 423         hpi_send_recv_ex(&hm, &hr, HOWNER_KERNEL);
 424
 425         if (hr.error) {
 426                 HPI_DEBUG_LOG(ERROR, "HPI_ADAPTER_OPEN failed, aborting\n");
 427                 goto err;
 428         }
 429
 430         /* Check if current mode == Low Latency mode */
 431         hpi_init_message_response(&hm, &hr, HPI_OBJ_ADAPTER,
 432                 HPI_ADAPTER_GET_MODE);
 433         hm.adapter_index = adapter.adapter->index;
 434         hpi_send_recv_ex(&hm, &hr, HOWNER_KERNEL);
 435
 436         if (!hr.error
 437                 && hr.u.ax.mode.adapter_mode == HPI_ADAPTER_MODE_LOW_LATENCY)
 438                 low_latency_mode = 1;
 439         else
 440                 dev_info(&pci_dev->dev,
 441                         "Adapter at index %d is not in low latency mode\n",
 442                         adapter.adapter->index);
 443
 444         /* Check if IRQs are supported */
 445         hpi_init_message_response(&hm, &hr, HPI_OBJ_ADAPTER,
 446                 HPI_ADAPTER_GET_PROPERTY);
 447         hm.adapter_index = adapter.adapter->index;
 448         hm.u.ax.property_set.property = HPI_ADAPTER_PROPERTY_SUPPORTS_IRQ;
 449         hpi_send_recv_ex(&hm, &hr, HOWNER_KERNEL);
 450         if (hr.error || !hr.u.ax.property_get.parameter1) {
 451                 dev_info(&pci_dev->dev,
 452                         "IRQs not supported by adapter at index %d\n",
 453                         adapter.adapter->index);
 454         } else {
 455                 irq_supported = 1;
 456         }
 457
 458         /* WARNING can't init mutex in 'adapter'
 459          * and then copy it to adapters[] ?!?!
 460          */
 461         adapters[adapter_index] = adapter;
 462         mutex_init(&adapters[adapter_index].mutex);
 463         pci_set_drvdata(pci_dev, &adapters[adapter_index]);
 464
 465         if (low_latency_mode && irq_supported) {
 466                 if (!adapter.adapter->irq_query_and_clear) {
 467                         dev_err(&pci_dev->dev,
 468                                 "no IRQ handler for adapter %d, aborting\n",
 469                                 adapter.adapter->index);
 470                         goto err;
 471                 }
 472
 473                 /* Disable IRQ generation on DSP side by setting the rate to 0 */
 474                 hpi_init_message_response(&hm, &hr, HPI_OBJ_ADAPTER,
 475                         HPI_ADAPTER_SET_PROPERTY);
 476                 hm.adapter_index = adapter.adapter->index;
 477                 hm.u.ax.property_set.property = HPI_ADAPTER_PROPERTY_IRQ_RATE;
 478                 hm.u.ax.property_set.parameter1 = 0;
 479                 hm.u.ax.property_set.parameter2 = 0;
 480                 hpi_send_recv_ex(&hm, &hr, HOWNER_KERNEL);
 481                 if (hr.error) {
 482                         HPI_DEBUG_LOG(ERROR,
 483                                 "HPI_ADAPTER_GET_MODE failed, aborting\n");
 484                         goto err;
 485                 }
 486
 487                 /* Note: request_irq calls asihpi_isr here */
 488                 if (request_irq(pci_dev->irq, asihpi_isr, IRQF_SHARED,
 489                                 "asihpi", &adapters[adapter_index])) {
 490                         dev_err(&pci_dev->dev, "request_irq(%d) failed\n",
 491                                 pci_dev->irq);
 492                         goto err;
 493                 }
 494
 495                 adapters[adapter_index].interrupt_mode = 1;
 496
 497                 dev_info(&pci_dev->dev, "using irq %d\n", pci_dev->irq);
 498                 adapters[adapter_index].irq = pci_dev->irq;
 499         } else {
 500                 dev_info(&pci_dev->dev, "using polled mode\n");
 501         }
 502
 503         dev_info(&pci_dev->dev, "probe succeeded for ASI%04X HPI index %d\n",
 504                  adapter.adapter->type, adapter_index);
 505
 506         return 0;
 507
 508 err:
 509         for (idx = 0; idx < HPI_MAX_ADAPTER_MEM_SPACES; idx++) {
 510                 if (pci.ap_mem_base[idx]) {
 511                         iounmap(pci.ap_mem_base[idx]);
 512                         pci.ap_mem_base[idx] = NULL;
 513                 }
 514         }
 515
 516         if (adapter.p_buffer) {
 517                 adapter.buffer_size = 0;
 518                 vfree(adapter.p_buffer);
 519         }
 520
 521         HPI_DEBUG_LOG(ERROR, "adapter_probe failed\n");
 522         return -ENODEV;
 523 }
 524
 525 void asihpi_adapter_remove(struct pci_dev *pci_dev)
 526 {
 527         int idx;
 528         struct hpi_message hm;
 529         struct hpi_response hr;
 530         struct hpi_adapter *pa;
 531         struct hpi_pci pci;
 532
 533         pa = pci_get_drvdata(pci_dev);
 534         pci = pa->adapter->pci;
 535
 536         /* Disable IRQ generation on DSP side */
 537         hpi_init_message_response(&hm, &hr, HPI_OBJ_ADAPTER,
 538                 HPI_ADAPTER_SET_PROPERTY);
 539         hm.adapter_index = pa->adapter->index;
 540         hm.u.ax.property_set.property = HPI_ADAPTER_PROPERTY_IRQ_RATE;
 541         hm.u.ax.property_set.parameter1 = 0;
 542         hm.u.ax.property_set.parameter2 = 0;
 543         hpi_send_recv_ex(&hm, &hr, HOWNER_KERNEL);
 544
 545         hpi_init_message_response(&hm, &hr, HPI_OBJ_ADAPTER,
 546                 HPI_ADAPTER_DELETE);
 547         hm.adapter_index = pa->adapter->index;
 548         hpi_send_recv_ex(&hm, &hr, HOWNER_KERNEL);
 549
 550         /* unmap PCI memory space, mapped during device init. */
 551         for (idx = 0; idx < HPI_MAX_ADAPTER_MEM_SPACES; ++idx)
 552                 iounmap(pci.ap_mem_base[idx]);
 553
 554         if (pa->irq)
 555                 free_irq(pa->irq, pa);
 556
 557         vfree(pa->p_buffer);
 558
 559         if (1)
 560                 dev_info(&pci_dev->dev,
 561                          "remove %04x:%04x,%04x:%04x,%04x, HPI index %d\n",
 562                          pci_dev->vendor, pci_dev->device,
 563                          pci_dev->subsystem_vendor, pci_dev->subsystem_device,
 564                          pci_dev->devfn, pa->adapter->index);
 565
 566         memset(pa, 0, sizeof(*pa));
 567 }
 568
 569 void __init asihpi_init(void)
 570 {
 571         struct hpi_message hm;
 572         struct hpi_response hr;
 573
 574         memset(adapters, 0, sizeof(adapters));
 575
 576         printk(KERN_INFO "ASIHPI driver " HPI_VER_STRING "\n");
 577
 578         hpi_init_message_response(&hm, &hr, HPI_OBJ_SUBSYSTEM,
 579                 HPI_SUBSYS_DRIVER_LOAD);
 580         hpi_send_recv_ex(&hm, &hr, HOWNER_KERNEL);
 581 }
 582
 583 void asihpi_exit(void)
 584 {
 585         struct hpi_message hm;
 586         struct hpi_response hr;
 587
 588         hpi_init_message_response(&hm, &hr, HPI_OBJ_SUBSYSTEM,
 589                 HPI_SUBSYS_DRIVER_UNLOAD);
 590         hpi_send_recv_ex(&hm, &hr, HOWNER_KERNEL);
 591 }