sound/firewire/fireworks/fireworks_transaction.c

   1 /*
   2  * fireworks_transaction.c - a part of driver for Fireworks based devices
   3  *
   4  * Copyright (c) 2013-2014 Takashi Sakamoto
   5  *
   6  * Licensed under the terms of the GNU General Public License, version 2.
   7  */
   8
   9 /*
  10  * Fireworks have its own transaction. The transaction can be delivered by AV/C
  11  * Vendor Specific command frame or usual asynchronous transaction. At least,
  12  * Windows driver and firmware version 5.5 or later don't use AV/C command.
  13  *
  14  * Transaction substance:
  15  *  At first, 6 data exist. Following to the data, parameters for each command
  16  *  exist. All of the parameters are 32 bit aligned to big endian.
  17  *   data[0]:   Length of transaction substance
  18  *   data[1]:   Transaction version
  19  *   data[2]:   Sequence number. This is incremented by the device
  20  *   data[3]:   Transaction category
  21  *   data[4]:   Transaction command
  22  *   data[5]:   Return value in response.
  23  *   data[6-]:  Parameters
  24  *
  25  * Transaction address:
  26  *  command:    0xecc000000000
  27  *  response:   0xecc080000000 (default)
  28  *
  29  * I note that the address for response can be changed by command. But this
  30  * module uses the default address.
  31  */
  32 #include "./fireworks.h"
  33
  34 #define MEMORY_SPACE_EFW_COMMAND        0xecc000000000ULL
  35 #define MEMORY_SPACE_EFW_RESPONSE       0xecc080000000ULL
  36
  37 #define ERROR_RETRIES 3
  38 #define ERROR_DELAY_MS 5
  39 #define EFC_TIMEOUT_MS 125
  40
  41 static DEFINE_SPINLOCK(instances_lock);
  42 static struct snd_efw *instances[SNDRV_CARDS] = SNDRV_DEFAULT_PTR;
  43
  44 static DEFINE_SPINLOCK(transaction_queues_lock);
  45 static LIST_HEAD(transaction_queues);
  46
  47 enum transaction_queue_state {
  48         STATE_PENDING,
  49         STATE_BUS_RESET,
  50         STATE_COMPLETE
  51 };
  52
  53 struct transaction_queue {
  54         struct list_head list;
  55         struct fw_unit *unit;
  56         void *buf;
  57         unsigned int size;
  58         u32 seqnum;
  59         enum transaction_queue_state state;
  60         wait_queue_head_t wait;
  61 };
  62
  63 int snd_efw_transaction_cmd(struct fw_unit *unit,
  64                             const void *cmd, unsigned int size)
  65 {
  66         return snd_fw_transaction(unit, TCODE_WRITE_BLOCK_REQUEST,
  67                                   MEMORY_SPACE_EFW_COMMAND,
  68                                   (void *)cmd, size, 0);
  69 }
  70
  71 int snd_efw_transaction_run(struct fw_unit *unit,
  72                             const void *cmd, unsigned int cmd_size,
  73                             void *resp, unsigned int resp_size)
  74 {
  75         struct transaction_queue t;
  76         unsigned int tries;
  77         int ret;
  78
  79         t.unit = unit;
  80         t.buf = resp;
  81         t.size = resp_size;
  82         t.seqnum = be32_to_cpu(((struct snd_efw_transaction *)cmd)->seqnum) + 1;
  83         t.state = STATE_PENDING;
  84         init_waitqueue_head(&t.wait);
  85
  86         spin_lock_irq(&transaction_queues_lock);
  87         list_add_tail(&t.list, &transaction_queues);
  88         spin_unlock_irq(&transaction_queues_lock);
  89
  90         tries = 0;
  91         do {
  92                 ret = snd_efw_transaction_cmd(t.unit, (void *)cmd, cmd_size);
  93                 if (ret < 0)
  94                         break;
  95
  96                 wait_event_timeout(t.wait, t.state != STATE_PENDING,
  97                                    msecs_to_jiffies(EFC_TIMEOUT_MS));
  98
  99                 if (t.state == STATE_COMPLETE) {
 100                         ret = t.size;
 101                         break;
 102                 } else if (t.state == STATE_BUS_RESET) {
 103                         msleep(ERROR_DELAY_MS);
 104                 } else if (++tries >= ERROR_RETRIES) {
 105                         dev_err(&t.unit->device, "EFW transaction timed out\n");
 106                         ret = -EIO;
 107                         break;
 108                 }
 109         } while (1);
 110
 111         spin_lock_irq(&transaction_queues_lock);
 112         list_del(&t.list);
 113         spin_unlock_irq(&transaction_queues_lock);
 114
 115         return ret;
 116 }
 117
 118 static void
 119 copy_resp_to_buf(struct snd_efw *efw, void *data, size_t length, int *rcode)
 120 {
 121         size_t capacity, till_end;
 122         struct snd_efw_transaction *t;
 123
 124         t = (struct snd_efw_transaction *)data;
 125         length = min_t(size_t, be32_to_cpu(t->length) * sizeof(u32), length);
 126
 127         spin_lock_irq(&efw->lock);
 128
 129         if (efw->push_ptr < efw->pull_ptr)
 130                 capacity = (unsigned int)(efw->pull_ptr - efw->push_ptr);
 131         else
 132                 capacity = snd_efw_resp_buf_size -
 133                            (unsigned int)(efw->push_ptr - efw->pull_ptr);
 134
 135         /* confirm enough space for this response */
 136         if (capacity < length) {
 137                 *rcode = RCODE_CONFLICT_ERROR;
 138                 goto end;
 139         }
 140
 141         /* copy to ring buffer */
 142         while (length > 0) {
 143                 till_end = snd_efw_resp_buf_size -
 144                            (unsigned int)(efw->push_ptr - efw->resp_buf);
 145                 till_end = min_t(unsigned int, length, till_end);
 146
 147                 memcpy(efw->push_ptr, data, till_end);
 148
 149                 efw->push_ptr += till_end;
 150                 if (efw->push_ptr >= efw->resp_buf + snd_efw_resp_buf_size)
 151                         efw->push_ptr -= snd_efw_resp_buf_size;
 152
 153                 length -= till_end;
 154                 data += till_end;
 155         }
 156
 157         /* for hwdep */
 158         wake_up(&efw->hwdep_wait);
 159
 160         *rcode = RCODE_COMPLETE;
 161 end:
 162         spin_unlock_irq(&efw->lock);
 163 }
 164
 165 static void
 166 handle_resp_for_user(struct fw_card *card, int generation, int source,
 167                      void *data, size_t length, int *rcode)
 168 {
 169         struct fw_device *device;
 170         struct snd_efw *efw;
 171         unsigned int i;
 172
 173         spin_lock_irq(&instances_lock);
 174
 175         for (i = 0; i < SNDRV_CARDS; i++) {
 176                 efw = instances[i];
 177                 if (efw == NULL)
 178                         continue;
 179                 device = fw_parent_device(efw->unit);
 180                 if ((device->card != card) ||
 181                     (device->generation != generation))
 182                         continue;
 183                 smp_rmb();      /* node id vs. generation */
 184                 if (device->node_id != source)
 185                         continue;
 186
 187                 break;
 188         }
 189         if (i == SNDRV_CARDS)
 190                 goto end;
 191
 192         copy_resp_to_buf(efw, data, length, rcode);
 193 end:
 194         spin_unlock_irq(&instances_lock);
 195 }
 196
 197 static void
 198 handle_resp_for_kernel(struct fw_card *card, int generation, int source,
 199                        void *data, size_t length, int *rcode, u32 seqnum)
 200 {
 201         struct fw_device *device;
 202         struct transaction_queue *t;
 203         unsigned long flags;
 204
 205         spin_lock_irqsave(&transaction_queues_lock, flags);
 206         list_for_each_entry(t, &transaction_queues, list) {
 207                 device = fw_parent_device(t->unit);
 208                 if ((device->card != card) ||
 209                     (device->generation != generation))
 210                         continue;
 211                 smp_rmb();      /* node_id vs. generation */
 212                 if (device->node_id != source)
 213                         continue;
 214
 215                 if ((t->state == STATE_PENDING) && (t->seqnum == seqnum)) {
 216                         t->state = STATE_COMPLETE;
 217                         t->size = min_t(unsigned int, length, t->size);
 218                         memcpy(t->buf, data, t->size);
 219                         wake_up(&t->wait);
 220                         *rcode = RCODE_COMPLETE;
 221                 }
 222         }
 223         spin_unlock_irqrestore(&transaction_queues_lock, flags);
 224 }
 225
 226 static void
 227 efw_response(struct fw_card *card, struct fw_request *request,
 228              int tcode, int destination, int source,
 229              int generation, unsigned long long offset,
 230              void *data, size_t length, void *callback_data)
 231 {
 232         int rcode, dummy;
 233         u32 seqnum;
 234
 235         rcode = RCODE_TYPE_ERROR;
 236         if (length < sizeof(struct snd_efw_transaction)) {
 237                 rcode = RCODE_DATA_ERROR;
 238                 goto end;
 239         } else if (offset != MEMORY_SPACE_EFW_RESPONSE) {
 240                 rcode = RCODE_ADDRESS_ERROR;
 241                 goto end;
 242         }
 243
 244         seqnum = be32_to_cpu(((struct snd_efw_transaction *)data)->seqnum);
 245         if (seqnum > SND_EFW_TRANSACTION_USER_SEQNUM_MAX + 1) {
 246                 handle_resp_for_kernel(card, generation, source,
 247                                        data, length, &rcode, seqnum);
 248                 if (snd_efw_resp_buf_debug)
 249                         handle_resp_for_user(card, generation, source,
 250                                              data, length, &dummy);
 251         } else {
 252                 handle_resp_for_user(card, generation, source,
 253                                      data, length, &rcode);
 254         }
 255 end:
 256         fw_send_response(card, request, rcode);
 257 }
 258
 259 void snd_efw_transaction_add_instance(struct snd_efw *efw)
 260 {
 261         unsigned int i;
 262
 263         spin_lock_irq(&instances_lock);
 264
 265         for (i = 0; i < SNDRV_CARDS; i++) {
 266                 if (instances[i] != NULL)
 267                         continue;
 268                 instances[i] = efw;
 269                 break;
 270         }
 271
 272         spin_unlock_irq(&instances_lock);
 273 }
 274
 275 void snd_efw_transaction_remove_instance(struct snd_efw *efw)
 276 {
 277         unsigned int i;
 278
 279         spin_lock_irq(&instances_lock);
 280
 281         for (i = 0; i < SNDRV_CARDS; i++) {
 282                 if (instances[i] != efw)
 283                         continue;
 284                 instances[i] = NULL;
 285         }
 286
 287         spin_unlock_irq(&instances_lock);
 288 }
 289
 290 void snd_efw_transaction_bus_reset(struct fw_unit *unit)
 291 {
 292         struct transaction_queue *t;
 293
 294         spin_lock_irq(&transaction_queues_lock);
 295         list_for_each_entry(t, &transaction_queues, list) {
 296                 if ((t->unit == unit) &&
 297                     (t->state == STATE_PENDING)) {
 298                         t->state = STATE_BUS_RESET;
 299                         wake_up(&t->wait);
 300                 }
 301         }
 302         spin_unlock_irq(&transaction_queues_lock);
 303 }
 304
 305 static struct fw_address_handler resp_register_handler = {
 306         .length = SND_EFW_RESPONSE_MAXIMUM_BYTES,
 307         .address_callback = efw_response
 308 };
 309
 310 int snd_efw_transaction_register(void)
 311 {
 312         static const struct fw_address_region resp_register_region = {
 313                 .start  = MEMORY_SPACE_EFW_RESPONSE,
 314                 .end    = MEMORY_SPACE_EFW_RESPONSE +
 315                           SND_EFW_RESPONSE_MAXIMUM_BYTES
 316         };
 317         return fw_core_add_address_handler(&resp_register_handler,
 318                                            &resp_register_region);
 319 }
 320
 321 void snd_efw_transaction_unregister(void)
 322 {
 323         WARN_ON(!list_empty(&transaction_queues));
 324         fw_core_remove_address_handler(&resp_register_handler);
 325 }