drivers/net/wireless/wl12xx/spi.c

   1 /*
   2  * This file is part of wl1271
   3  *
   4  * Copyright (C) 2008-2009 Nokia Corporation
   5  *
   6  * Contact: Luciano Coelho <luciano.coelho@nokia.com>
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License
  10  * version 2 as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  *
  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., 51 Franklin St, Fifth Floor, Boston, MA
  20  * 02110-1301 USA
  21  *
  22  */
  23
  24 #include <linux/irq.h>
  25 #include <linux/module.h>
  26 #include <linux/crc7.h>
  27 #include <linux/spi/spi.h>
  28 #include <linux/wl12xx.h>
  29 #include <linux/slab.h>
  30
  31 #include "wl12xx.h"
  32 #include "wl12xx_80211.h"
  33 #include "io.h"
  34
  35 #include "reg.h"
  36
  37 #define WSPI_CMD_READ                 0x40000000
  38 #define WSPI_CMD_WRITE                0x00000000
  39 #define WSPI_CMD_FIXED                0x20000000
  40 #define WSPI_CMD_BYTE_LENGTH          0x1FFE0000
  41 #define WSPI_CMD_BYTE_LENGTH_OFFSET   17
  42 #define WSPI_CMD_BYTE_ADDR            0x0001FFFF
  43
  44 #define WSPI_INIT_CMD_CRC_LEN       5
  45
  46 #define WSPI_INIT_CMD_START         0x00
  47 #define WSPI_INIT_CMD_TX            0x40
  48 /* the extra bypass bit is sampled by the TNET as '1' */
  49 #define WSPI_INIT_CMD_BYPASS_BIT    0x80
  50 #define WSPI_INIT_CMD_FIXEDBUSY_LEN 0x07
  51 #define WSPI_INIT_CMD_EN_FIXEDBUSY  0x80
  52 #define WSPI_INIT_CMD_DIS_FIXEDBUSY 0x00
  53 #define WSPI_INIT_CMD_IOD           0x40
  54 #define WSPI_INIT_CMD_IP            0x20
  55 #define WSPI_INIT_CMD_CS            0x10
  56 #define WSPI_INIT_CMD_WS            0x08
  57 #define WSPI_INIT_CMD_WSPI          0x01
  58 #define WSPI_INIT_CMD_END           0x01
  59
  60 #define WSPI_INIT_CMD_LEN           8
  61
  62 #define HW_ACCESS_WSPI_FIXED_BUSY_LEN \
  63                 ((WL1271_BUSY_WORD_LEN - 4) / sizeof(u32))
  64 #define HW_ACCESS_WSPI_INIT_CMD_MASK  0
  65
  66 /* HW limitation: maximum possible chunk size is 4095 bytes */
  67 #define WSPI_MAX_CHUNK_SIZE    4092
  68
  69 #define WSPI_MAX_NUM_OF_CHUNKS (WL1271_AGGR_BUFFER_SIZE / WSPI_MAX_CHUNK_SIZE)
  70
  71 static inline struct spi_device *wl_to_spi(struct wl1271 *wl)
  72 {
  73         return wl->if_priv;
  74 }
  75
  76 static struct device *wl1271_spi_wl_to_dev(struct wl1271 *wl)
  77 {
  78         return &(wl_to_spi(wl)->dev);
  79 }
  80
  81 static void wl1271_spi_disable_interrupts(struct wl1271 *wl)
  82 {
  83         disable_irq(wl->irq);
  84 }
  85
  86 static void wl1271_spi_enable_interrupts(struct wl1271 *wl)
  87 {
  88         enable_irq(wl->irq);
  89 }
  90
  91 static void wl1271_spi_reset(struct wl1271 *wl)
  92 {
  93         u8 *cmd;
  94         struct spi_transfer t;
  95         struct spi_message m;
  96
  97         cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
  98         if (!cmd) {
  99                 wl1271_error("could not allocate cmd for spi reset");
 100                 return;
 101         }
 102
 103         memset(&t, 0, sizeof(t));
 104         spi_message_init(&m);
 105
 106         memset(cmd, 0xff, WSPI_INIT_CMD_LEN);
 107
 108         t.tx_buf = cmd;
 109         t.len = WSPI_INIT_CMD_LEN;
 110         spi_message_add_tail(&t, &m);
 111
 112         spi_sync(wl_to_spi(wl), &m);
 113         kfree(cmd);
 114
 115         wl1271_dump(DEBUG_SPI, "spi reset -> ", cmd, WSPI_INIT_CMD_LEN);
 116 }
 117
 118 static void wl1271_spi_init(struct wl1271 *wl)
 119 {
 120         u8 crc[WSPI_INIT_CMD_CRC_LEN], *cmd;
 121         struct spi_transfer t;
 122         struct spi_message m;
 123
 124         cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
 125         if (!cmd) {
 126                 wl1271_error("could not allocate cmd for spi init");
 127                 return;
 128         }
 129
 130         memset(crc, 0, sizeof(crc));
 131         memset(&t, 0, sizeof(t));
 132         spi_message_init(&m);
 133
 134         /*
 135          * Set WSPI_INIT_COMMAND
 136          * the data is being send from the MSB to LSB
 137          */
 138         cmd[2] = 0xff;
 139         cmd[3] = 0xff;
 140         cmd[1] = WSPI_INIT_CMD_START | WSPI_INIT_CMD_TX;
 141         cmd[0] = 0;
 142         cmd[7] = 0;
 143         cmd[6] |= HW_ACCESS_WSPI_INIT_CMD_MASK << 3;
 144         cmd[6] |= HW_ACCESS_WSPI_FIXED_BUSY_LEN & WSPI_INIT_CMD_FIXEDBUSY_LEN;
 145
 146         if (HW_ACCESS_WSPI_FIXED_BUSY_LEN == 0)
 147                 cmd[5] |=  WSPI_INIT_CMD_DIS_FIXEDBUSY;
 148         else
 149                 cmd[5] |= WSPI_INIT_CMD_EN_FIXEDBUSY;
 150
 151         cmd[5] |= WSPI_INIT_CMD_IOD | WSPI_INIT_CMD_IP | WSPI_INIT_CMD_CS
 152                 | WSPI_INIT_CMD_WSPI | WSPI_INIT_CMD_WS;
 153
 154         crc[0] = cmd[1];
 155         crc[1] = cmd[0];
 156         crc[2] = cmd[7];
 157         crc[3] = cmd[6];
 158         crc[4] = cmd[5];
 159
 160         cmd[4] |= crc7(0, crc, WSPI_INIT_CMD_CRC_LEN) << 1;
 161         cmd[4] |= WSPI_INIT_CMD_END;
 162
 163         t.tx_buf = cmd;
 164         t.len = WSPI_INIT_CMD_LEN;
 165         spi_message_add_tail(&t, &m);
 166
 167         spi_sync(wl_to_spi(wl), &m);
 168         wl1271_dump(DEBUG_SPI, "spi init -> ", cmd, WSPI_INIT_CMD_LEN);
 169         kfree(cmd);
 170 }
 171
 172 #define WL1271_BUSY_WORD_TIMEOUT 1000
 173
 174 static int wl1271_spi_read_busy(struct wl1271 *wl)
 175 {
 176         struct spi_transfer t[1];
 177         struct spi_message m;
 178         u32 *busy_buf;
 179         int num_busy_bytes = 0;
 180
 181         /*
 182          * Read further busy words from SPI until a non-busy word is
 183          * encountered, then read the data itself into the buffer.
 184          */
 185
 186         num_busy_bytes = WL1271_BUSY_WORD_TIMEOUT;
 187         busy_buf = wl->buffer_busyword;
 188         while (num_busy_bytes) {
 189                 num_busy_bytes--;
 190                 spi_message_init(&m);
 191                 memset(t, 0, sizeof(t));
 192                 t[0].rx_buf = busy_buf;
 193                 t[0].len = sizeof(u32);
 194                 t[0].cs_change = true;
 195                 spi_message_add_tail(&t[0], &m);
 196                 spi_sync(wl_to_spi(wl), &m);
 197
 198                 if (*busy_buf & 0x1)
 199                         return 0;
 200         }
 201
 202         /* The SPI bus is unresponsive, the read failed. */
 203         wl1271_error("SPI read busy-word timeout!\n");
 204         return -ETIMEDOUT;
 205 }
 206
 207 static void wl1271_spi_raw_read(struct wl1271 *wl, int addr, void *buf,
 208                                 size_t len, bool fixed)
 209 {
 210         struct spi_transfer t[2];
 211         struct spi_message m;
 212         u32 *busy_buf;
 213         u32 *cmd;
 214         u32 chunk_len;
 215
 216         while (len > 0) {
 217                 chunk_len = min((size_t)WSPI_MAX_CHUNK_SIZE, len);
 218
 219                 cmd = &wl->buffer_cmd;
 220                 busy_buf = wl->buffer_busyword;
 221
 222                 *cmd = 0;
 223                 *cmd |= WSPI_CMD_READ;
 224                 *cmd |= (chunk_len << WSPI_CMD_BYTE_LENGTH_OFFSET) &
 225                         WSPI_CMD_BYTE_LENGTH;
 226                 *cmd |= addr & WSPI_CMD_BYTE_ADDR;
 227
 228                 if (fixed)
 229                         *cmd |= WSPI_CMD_FIXED;
 230
 231                 spi_message_init(&m);
 232                 memset(t, 0, sizeof(t));
 233
 234                 t[0].tx_buf = cmd;
 235                 t[0].len = 4;
 236                 t[0].cs_change = true;
 237                 spi_message_add_tail(&t[0], &m);
 238
 239                 /* Busy and non busy words read */
 240                 t[1].rx_buf = busy_buf;
 241                 t[1].len = WL1271_BUSY_WORD_LEN;
 242                 t[1].cs_change = true;
 243                 spi_message_add_tail(&t[1], &m);
 244
 245                 spi_sync(wl_to_spi(wl), &m);
 246
 247                 if (!(busy_buf[WL1271_BUSY_WORD_CNT - 1] & 0x1) &&
 248                     wl1271_spi_read_busy(wl)) {
 249                         memset(buf, 0, chunk_len);
 250                         return;
 251                 }
 252
 253                 spi_message_init(&m);
 254                 memset(t, 0, sizeof(t));
 255
 256                 t[0].rx_buf = buf;
 257                 t[0].len = chunk_len;
 258                 t[0].cs_change = true;
 259                 spi_message_add_tail(&t[0], &m);
 260
 261                 spi_sync(wl_to_spi(wl), &m);
 262
 263                 wl1271_dump(DEBUG_SPI, "spi_read cmd -> ", cmd, sizeof(*cmd));
 264                 wl1271_dump(DEBUG_SPI, "spi_read buf <- ", buf, chunk_len);
 265
 266                 if (!fixed)
 267                         addr += chunk_len;
 268                 buf += chunk_len;
 269                 len -= chunk_len;
 270         }
 271 }
 272
 273 static void wl1271_spi_raw_write(struct wl1271 *wl, int addr, void *buf,
 274                           size_t len, bool fixed)
 275 {
 276         struct spi_transfer t[2 * WSPI_MAX_NUM_OF_CHUNKS];
 277         struct spi_message m;
 278         u32 commands[WSPI_MAX_NUM_OF_CHUNKS];
 279         u32 *cmd;
 280         u32 chunk_len;
 281         int i;
 282
 283         WARN_ON(len > WL1271_AGGR_BUFFER_SIZE);
 284
 285         spi_message_init(&m);
 286         memset(t, 0, sizeof(t));
 287
 288         cmd = &commands[0];
 289         i = 0;
 290         while (len > 0) {
 291                 chunk_len = min((size_t)WSPI_MAX_CHUNK_SIZE, len);
 292
 293                 *cmd = 0;
 294                 *cmd |= WSPI_CMD_WRITE;
 295                 *cmd |= (chunk_len << WSPI_CMD_BYTE_LENGTH_OFFSET) &
 296                         WSPI_CMD_BYTE_LENGTH;
 297                 *cmd |= addr & WSPI_CMD_BYTE_ADDR;
 298
 299                 if (fixed)
 300                         *cmd |= WSPI_CMD_FIXED;
 301
 302                 t[i].tx_buf = cmd;
 303                 t[i].len = sizeof(*cmd);
 304                 spi_message_add_tail(&t[i++], &m);
 305
 306                 t[i].tx_buf = buf;
 307                 t[i].len = chunk_len;
 308                 spi_message_add_tail(&t[i++], &m);
 309
 310                 wl1271_dump(DEBUG_SPI, "spi_write cmd -> ", cmd, sizeof(*cmd));
 311                 wl1271_dump(DEBUG_SPI, "spi_write buf -> ", buf, chunk_len);
 312
 313                 if (!fixed)
 314                         addr += chunk_len;
 315                 buf += chunk_len;
 316                 len -= chunk_len;
 317                 cmd++;
 318         }
 319
 320         spi_sync(wl_to_spi(wl), &m);
 321 }
 322
 323 static irqreturn_t wl1271_irq(int irq, void *cookie)
 324 {
 325         struct wl1271 *wl;
 326         unsigned long flags;
 327
 328         wl1271_debug(DEBUG_IRQ, "IRQ");
 329
 330         wl = cookie;
 331
 332         /* complete the ELP completion */
 333         spin_lock_irqsave(&wl->wl_lock, flags);
 334         if (wl->elp_compl) {
 335                 complete(wl->elp_compl);
 336                 wl->elp_compl = NULL;
 337         }
 338
 339         if (!test_and_set_bit(WL1271_FLAG_IRQ_RUNNING, &wl->flags))
 340                 ieee80211_queue_work(wl->hw, &wl->irq_work);
 341         set_bit(WL1271_FLAG_IRQ_PENDING, &wl->flags);
 342         spin_unlock_irqrestore(&wl->wl_lock, flags);
 343
 344         return IRQ_HANDLED;
 345 }
 346
 347 static int wl1271_spi_set_power(struct wl1271 *wl, bool enable)
 348 {
 349         if (wl->set_power)
 350                 wl->set_power(enable);
 351
 352         return 0;
 353 }
 354
 355 static struct wl1271_if_operations spi_ops = {
 356         .read           = wl1271_spi_raw_read,
 357         .write          = wl1271_spi_raw_write,
 358         .reset          = wl1271_spi_reset,
 359         .init           = wl1271_spi_init,
 360         .power          = wl1271_spi_set_power,
 361         .dev            = wl1271_spi_wl_to_dev,
 362         .enable_irq     = wl1271_spi_enable_interrupts,
 363         .disable_irq    = wl1271_spi_disable_interrupts
 364 };
 365
 366 static int __devinit wl1271_probe(struct spi_device *spi)
 367 {
 368         struct wl12xx_platform_data *pdata;
 369         struct ieee80211_hw *hw;
 370         struct wl1271 *wl;
 371         int ret;
 372
 373         pdata = spi->dev.platform_data;
 374         if (!pdata) {
 375                 wl1271_error("no platform data");
 376                 return -ENODEV;
 377         }
 378
 379         hw = wl1271_alloc_hw();
 380         if (IS_ERR(hw))
 381                 return PTR_ERR(hw);
 382
 383         wl = hw->priv;
 384
 385         dev_set_drvdata(&spi->dev, wl);
 386         wl->if_priv = spi;
 387
 388         wl->if_ops = &spi_ops;
 389
 390         /* This is the only SPI value that we need to set here, the rest
 391          * comes from the board-peripherals file */
 392         spi->bits_per_word = 32;
 393
 394         ret = spi_setup(spi);
 395         if (ret < 0) {
 396                 wl1271_error("spi_setup failed");
 397                 goto out_free;
 398         }
 399
 400         wl->set_power = pdata->set_power;
 401         if (!wl->set_power) {
 402                 wl1271_error("set power function missing in platform data");
 403                 ret = -ENODEV;
 404                 goto out_free;
 405         }
 406
 407         wl->ref_clock = pdata->board_ref_clock;
 408
 409         wl->irq = spi->irq;
 410         if (wl->irq < 0) {
 411                 wl1271_error("irq missing in platform data");
 412                 ret = -ENODEV;
 413                 goto out_free;
 414         }
 415
 416         ret = request_irq(wl->irq, wl1271_irq, 0, DRIVER_NAME, wl);
 417         if (ret < 0) {
 418                 wl1271_error("request_irq() failed: %d", ret);
 419                 goto out_free;
 420         }
 421
 422         set_irq_type(wl->irq, IRQ_TYPE_EDGE_RISING);
 423
 424         disable_irq(wl->irq);
 425
 426         ret = wl1271_init_ieee80211(wl);
 427         if (ret)
 428                 goto out_irq;
 429
 430         ret = wl1271_register_hw(wl);
 431         if (ret)
 432                 goto out_irq;
 433
 434         wl1271_notice("initialized");
 435
 436         return 0;
 437
 438  out_irq:
 439         free_irq(wl->irq, wl);
 440
 441  out_free:
 442         wl1271_free_hw(wl);
 443
 444         return ret;
 445 }
 446
 447 static int __devexit wl1271_remove(struct spi_device *spi)
 448 {
 449         struct wl1271 *wl = dev_get_drvdata(&spi->dev);
 450
 451         wl1271_unregister_hw(wl);
 452         free_irq(wl->irq, wl);
 453         wl1271_free_hw(wl);
 454
 455         return 0;
 456 }
 457
 458
 459 static struct spi_driver wl1271_spi_driver = {
 460         .driver = {
 461                 .name           = "wl1271_spi",
 462                 .bus            = &spi_bus_type,
 463                 .owner          = THIS_MODULE,
 464         },
 465
 466         .probe          = wl1271_probe,
 467         .remove         = __devexit_p(wl1271_remove),
 468 };
 469
 470 static int __init wl1271_init(void)
 471 {
 472         int ret;
 473
 474         ret = spi_register_driver(&wl1271_spi_driver);
 475         if (ret < 0) {
 476                 wl1271_error("failed to register spi driver: %d", ret);
 477                 goto out;
 478         }
 479
 480 out:
 481         return ret;
 482 }
 483
 484 static void __exit wl1271_exit(void)
 485 {
 486         spi_unregister_driver(&wl1271_spi_driver);
 487
 488         wl1271_notice("unloaded");
 489 }
 490
 491 module_init(wl1271_init);
 492 module_exit(wl1271_exit);
 493
 494 MODULE_LICENSE("GPL");
 495 MODULE_AUTHOR("Luciano Coelho <luciano.coelho@nokia.com>");
 496 MODULE_AUTHOR("Juuso Oikarinen <juuso.oikarinen@nokia.com>");
 497 MODULE_FIRMWARE(WL1271_FW_NAME);
 498 MODULE_ALIAS("spi:wl1271");