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         wl1271_dump(DEBUG_SPI, "spi reset -> ", cmd, WSPI_INIT_CMD_LEN);
 114         kfree(cmd);
 115 }
 116
 117 static void wl1271_spi_init(struct wl1271 *wl)
 118 {
 119         u8 crc[WSPI_INIT_CMD_CRC_LEN], *cmd;
 120         struct spi_transfer t;
 121         struct spi_message m;
 122
 123         cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
 124         if (!cmd) {
 125                 wl1271_error("could not allocate cmd for spi init");
 126                 return;
 127         }
 128
 129         memset(crc, 0, sizeof(crc));
 130         memset(&t, 0, sizeof(t));
 131         spi_message_init(&m);
 132
 133         /*
 134          * Set WSPI_INIT_COMMAND
 135          * the data is being send from the MSB to LSB
 136          */
 137         cmd[2] = 0xff;
 138         cmd[3] = 0xff;
 139         cmd[1] = WSPI_INIT_CMD_START | WSPI_INIT_CMD_TX;
 140         cmd[0] = 0;
 141         cmd[7] = 0;
 142         cmd[6] |= HW_ACCESS_WSPI_INIT_CMD_MASK << 3;
 143         cmd[6] |= HW_ACCESS_WSPI_FIXED_BUSY_LEN & WSPI_INIT_CMD_FIXEDBUSY_LEN;
 144
 145         if (HW_ACCESS_WSPI_FIXED_BUSY_LEN == 0)
 146                 cmd[5] |=  WSPI_INIT_CMD_DIS_FIXEDBUSY;
 147         else
 148                 cmd[5] |= WSPI_INIT_CMD_EN_FIXEDBUSY;
 149
 150         cmd[5] |= WSPI_INIT_CMD_IOD | WSPI_INIT_CMD_IP | WSPI_INIT_CMD_CS
 151                 | WSPI_INIT_CMD_WSPI | WSPI_INIT_CMD_WS;
 152
 153         crc[0] = cmd[1];
 154         crc[1] = cmd[0];
 155         crc[2] = cmd[7];
 156         crc[3] = cmd[6];
 157         crc[4] = cmd[5];
 158
 159         cmd[4] |= crc7(0, crc, WSPI_INIT_CMD_CRC_LEN) << 1;
 160         cmd[4] |= WSPI_INIT_CMD_END;
 161
 162         t.tx_buf = cmd;
 163         t.len = WSPI_INIT_CMD_LEN;
 164         spi_message_add_tail(&t, &m);
 165
 166         spi_sync(wl_to_spi(wl), &m);
 167         wl1271_dump(DEBUG_SPI, "spi init -> ", cmd, WSPI_INIT_CMD_LEN);
 168         kfree(cmd);
 169 }
 170
 171 #define WL1271_BUSY_WORD_TIMEOUT 1000
 172
 173 static int wl1271_spi_read_busy(struct wl1271 *wl)
 174 {
 175         struct spi_transfer t[1];
 176         struct spi_message m;
 177         u32 *busy_buf;
 178         int num_busy_bytes = 0;
 179
 180         /*
 181          * Read further busy words from SPI until a non-busy word is
 182          * encountered, then read the data itself into the buffer.
 183          */
 184
 185         num_busy_bytes = WL1271_BUSY_WORD_TIMEOUT;
 186         busy_buf = wl->buffer_busyword;
 187         while (num_busy_bytes) {
 188                 num_busy_bytes--;
 189                 spi_message_init(&m);
 190                 memset(t, 0, sizeof(t));
 191                 t[0].rx_buf = busy_buf;
 192                 t[0].len = sizeof(u32);
 193                 t[0].cs_change = true;
 194                 spi_message_add_tail(&t[0], &m);
 195                 spi_sync(wl_to_spi(wl), &m);
 196
 197                 if (*busy_buf & 0x1)
 198                         return 0;
 199         }
 200
 201         /* The SPI bus is unresponsive, the read failed. */
 202         wl1271_error("SPI read busy-word timeout!\n");
 203         return -ETIMEDOUT;
 204 }
 205
 206 static void wl1271_spi_raw_read(struct wl1271 *wl, int addr, void *buf,
 207                                 size_t len, bool fixed)
 208 {
 209         struct spi_transfer t[2];
 210         struct spi_message m;
 211         u32 *busy_buf;
 212         u32 *cmd;
 213         u32 chunk_len;
 214
 215         while (len > 0) {
 216                 chunk_len = min((size_t)WSPI_MAX_CHUNK_SIZE, len);
 217
 218                 cmd = &wl->buffer_cmd;
 219                 busy_buf = wl->buffer_busyword;
 220
 221                 *cmd = 0;
 222                 *cmd |= WSPI_CMD_READ;
 223                 *cmd |= (chunk_len << WSPI_CMD_BYTE_LENGTH_OFFSET) &
 224                         WSPI_CMD_BYTE_LENGTH;
 225                 *cmd |= addr & WSPI_CMD_BYTE_ADDR;
 226
 227                 if (fixed)
 228                         *cmd |= WSPI_CMD_FIXED;
 229
 230                 spi_message_init(&m);
 231                 memset(t, 0, sizeof(t));
 232
 233                 t[0].tx_buf = cmd;
 234                 t[0].len = 4;
 235                 t[0].cs_change = true;
 236                 spi_message_add_tail(&t[0], &m);
 237
 238                 /* Busy and non busy words read */
 239                 t[1].rx_buf = busy_buf;
 240                 t[1].len = WL1271_BUSY_WORD_LEN;
 241                 t[1].cs_change = true;
 242                 spi_message_add_tail(&t[1], &m);
 243
 244                 spi_sync(wl_to_spi(wl), &m);
 245
 246                 if (!(busy_buf[WL1271_BUSY_WORD_CNT - 1] & 0x1) &&
 247                     wl1271_spi_read_busy(wl)) {
 248                         memset(buf, 0, chunk_len);
 249                         return;
 250                 }
 251
 252                 spi_message_init(&m);
 253                 memset(t, 0, sizeof(t));
 254
 255                 t[0].rx_buf = buf;
 256                 t[0].len = chunk_len;
 257                 t[0].cs_change = true;
 258                 spi_message_add_tail(&t[0], &m);
 259
 260                 spi_sync(wl_to_spi(wl), &m);
 261
 262                 wl1271_dump(DEBUG_SPI, "spi_read cmd -> ", cmd, sizeof(*cmd));
 263                 wl1271_dump(DEBUG_SPI, "spi_read buf <- ", buf, chunk_len);
 264
 265                 if (!fixed)
 266                         addr += chunk_len;
 267                 buf += chunk_len;
 268                 len -= chunk_len;
 269         }
 270 }
 271
 272 static void wl1271_spi_raw_write(struct wl1271 *wl, int addr, void *buf,
 273                           size_t len, bool fixed)
 274 {
 275         struct spi_transfer t[2 * WSPI_MAX_NUM_OF_CHUNKS];
 276         struct spi_message m;
 277         u32 commands[WSPI_MAX_NUM_OF_CHUNKS];
 278         u32 *cmd;
 279         u32 chunk_len;
 280         int i;
 281
 282         WARN_ON(len > WL1271_AGGR_BUFFER_SIZE);
 283
 284         spi_message_init(&m);
 285         memset(t, 0, sizeof(t));
 286
 287         cmd = &commands[0];
 288         i = 0;
 289         while (len > 0) {
 290                 chunk_len = min((size_t)WSPI_MAX_CHUNK_SIZE, len);
 291
 292                 *cmd = 0;
 293                 *cmd |= WSPI_CMD_WRITE;
 294                 *cmd |= (chunk_len << WSPI_CMD_BYTE_LENGTH_OFFSET) &
 295                         WSPI_CMD_BYTE_LENGTH;
 296                 *cmd |= addr & WSPI_CMD_BYTE_ADDR;
 297
 298                 if (fixed)
 299                         *cmd |= WSPI_CMD_FIXED;
 300
 301                 t[i].tx_buf = cmd;
 302                 t[i].len = sizeof(*cmd);
 303                 spi_message_add_tail(&t[i++], &m);
 304
 305                 t[i].tx_buf = buf;
 306                 t[i].len = chunk_len;
 307                 spi_message_add_tail(&t[i++], &m);
 308
 309                 wl1271_dump(DEBUG_SPI, "spi_write cmd -> ", cmd, sizeof(*cmd));
 310                 wl1271_dump(DEBUG_SPI, "spi_write buf -> ", buf, chunk_len);
 311
 312                 if (!fixed)
 313                         addr += chunk_len;
 314                 buf += chunk_len;
 315                 len -= chunk_len;
 316                 cmd++;
 317         }
 318
 319         spi_sync(wl_to_spi(wl), &m);
 320 }
 321
 322 static irqreturn_t wl1271_irq(int irq, void *cookie)
 323 {
 324         struct wl1271 *wl;
 325         unsigned long flags;
 326
 327         wl1271_debug(DEBUG_IRQ, "IRQ");
 328
 329         wl = cookie;
 330
 331         /* complete the ELP completion */
 332         spin_lock_irqsave(&wl->wl_lock, flags);
 333         if (wl->elp_compl) {
 334                 complete(wl->elp_compl);
 335                 wl->elp_compl = NULL;
 336         }
 337
 338         if (!test_and_set_bit(WL1271_FLAG_IRQ_RUNNING, &wl->flags))
 339                 ieee80211_queue_work(wl->hw, &wl->irq_work);
 340         set_bit(WL1271_FLAG_IRQ_PENDING, &wl->flags);
 341         spin_unlock_irqrestore(&wl->wl_lock, flags);
 342
 343         return IRQ_HANDLED;
 344 }
 345
 346 static int wl1271_spi_set_power(struct wl1271 *wl, bool enable)
 347 {
 348         if (wl->set_power)
 349                 wl->set_power(enable);
 350
 351         return 0;
 352 }
 353
 354 static struct wl1271_if_operations spi_ops = {
 355         .read           = wl1271_spi_raw_read,
 356         .write          = wl1271_spi_raw_write,
 357         .reset          = wl1271_spi_reset,
 358         .init           = wl1271_spi_init,
 359         .power          = wl1271_spi_set_power,
 360         .dev            = wl1271_spi_wl_to_dev,
 361         .enable_irq     = wl1271_spi_enable_interrupts,
 362         .disable_irq    = wl1271_spi_disable_interrupts
 363 };
 364
 365 static int __devinit wl1271_probe(struct spi_device *spi)
 366 {
 367         struct wl12xx_platform_data *pdata;
 368         struct ieee80211_hw *hw;
 369         struct wl1271 *wl;
 370         int ret;
 371
 372         pdata = spi->dev.platform_data;
 373         if (!pdata) {
 374                 wl1271_error("no platform data");
 375                 return -ENODEV;
 376         }
 377
 378         hw = wl1271_alloc_hw();
 379         if (IS_ERR(hw))
 380                 return PTR_ERR(hw);
 381
 382         wl = hw->priv;
 383
 384         dev_set_drvdata(&spi->dev, wl);
 385         wl->if_priv = spi;
 386
 387         wl->if_ops = &spi_ops;
 388
 389         /* This is the only SPI value that we need to set here, the rest
 390          * comes from the board-peripherals file */
 391         spi->bits_per_word = 32;
 392
 393         ret = spi_setup(spi);
 394         if (ret < 0) {
 395                 wl1271_error("spi_setup failed");
 396                 goto out_free;
 397         }
 398
 399         wl->set_power = pdata->set_power;
 400         if (!wl->set_power) {
 401                 wl1271_error("set power function missing in platform data");
 402                 ret = -ENODEV;
 403                 goto out_free;
 404         }
 405
 406         wl->ref_clock = pdata->board_ref_clock;
 407
 408         wl->irq = spi->irq;
 409         if (wl->irq < 0) {
 410                 wl1271_error("irq missing in platform data");
 411                 ret = -ENODEV;
 412                 goto out_free;
 413         }
 414
 415         ret = request_irq(wl->irq, wl1271_irq, 0, DRIVER_NAME, wl);
 416         if (ret < 0) {
 417                 wl1271_error("request_irq() failed: %d", ret);
 418                 goto out_free;
 419         }
 420
 421         set_irq_type(wl->irq, IRQ_TYPE_EDGE_RISING);
 422
 423         disable_irq(wl->irq);
 424
 425         ret = wl1271_init_ieee80211(wl);
 426         if (ret)
 427                 goto out_irq;
 428
 429         ret = wl1271_register_hw(wl);
 430         if (ret)
 431                 goto out_irq;
 432
 433         wl1271_notice("initialized");
 434
 435         return 0;
 436
 437  out_irq:
 438         free_irq(wl->irq, wl);
 439
 440  out_free:
 441         wl1271_free_hw(wl);
 442
 443         return ret;
 444 }
 445
 446 static int __devexit wl1271_remove(struct spi_device *spi)
 447 {
 448         struct wl1271 *wl = dev_get_drvdata(&spi->dev);
 449
 450         wl1271_unregister_hw(wl);
 451         free_irq(wl->irq, wl);
 452         wl1271_free_hw(wl);
 453
 454         return 0;
 455 }
 456
 457
 458 static struct spi_driver wl1271_spi_driver = {
 459         .driver = {
 460                 .name           = "wl1271_spi",
 461                 .bus            = &spi_bus_type,
 462                 .owner          = THIS_MODULE,
 463         },
 464
 465         .probe          = wl1271_probe,
 466         .remove         = __devexit_p(wl1271_remove),
 467 };
 468
 469 static int __init wl1271_init(void)
 470 {
 471         int ret;
 472
 473         ret = spi_register_driver(&wl1271_spi_driver);
 474         if (ret < 0) {
 475                 wl1271_error("failed to register spi driver: %d", ret);
 476                 goto out;
 477         }
 478
 479 out:
 480         return ret;
 481 }
 482
 483 static void __exit wl1271_exit(void)
 484 {
 485         spi_unregister_driver(&wl1271_spi_driver);
 486
 487         wl1271_notice("unloaded");
 488 }
 489
 490 module_init(wl1271_init);
 491 module_exit(wl1271_exit);
 492
 493 MODULE_LICENSE("GPL");
 494 MODULE_AUTHOR("Luciano Coelho <luciano.coelho@nokia.com>");
 495 MODULE_AUTHOR("Juuso Oikarinen <juuso.oikarinen@nokia.com>");
 496 MODULE_FIRMWARE(WL1271_FW_NAME);
 497 MODULE_ALIAS("spi:wl1271");