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/interrupt.h>
  25 #include <linux/irq.h>
  26 #include <linux/module.h>
  27 #include <linux/crc7.h>
  28 #include <linux/spi/spi.h>
  29 #include <linux/wl12xx.h>
  30 #include <linux/slab.h>
  31
  32 #include "wl12xx.h"
  33 #include "wl12xx_80211.h"
  34 #include "io.h"
  35
  36 #include "reg.h"
  37
  38 #define WSPI_CMD_READ                 0x40000000
  39 #define WSPI_CMD_WRITE                0x00000000
  40 #define WSPI_CMD_FIXED                0x20000000
  41 #define WSPI_CMD_BYTE_LENGTH          0x1FFE0000
  42 #define WSPI_CMD_BYTE_LENGTH_OFFSET   17
  43 #define WSPI_CMD_BYTE_ADDR            0x0001FFFF
  44
  45 #define WSPI_INIT_CMD_CRC_LEN       5
  46
  47 #define WSPI_INIT_CMD_START         0x00
  48 #define WSPI_INIT_CMD_TX            0x40
  49 /* the extra bypass bit is sampled by the TNET as '1' */
  50 #define WSPI_INIT_CMD_BYPASS_BIT    0x80
  51 #define WSPI_INIT_CMD_FIXEDBUSY_LEN 0x07
  52 #define WSPI_INIT_CMD_EN_FIXEDBUSY  0x80
  53 #define WSPI_INIT_CMD_DIS_FIXEDBUSY 0x00
  54 #define WSPI_INIT_CMD_IOD           0x40
  55 #define WSPI_INIT_CMD_IP            0x20
  56 #define WSPI_INIT_CMD_CS            0x10
  57 #define WSPI_INIT_CMD_WS            0x08
  58 #define WSPI_INIT_CMD_WSPI          0x01
  59 #define WSPI_INIT_CMD_END           0x01
  60
  61 #define WSPI_INIT_CMD_LEN           8
  62
  63 #define HW_ACCESS_WSPI_FIXED_BUSY_LEN \
  64                 ((WL1271_BUSY_WORD_LEN - 4) / sizeof(u32))
  65 #define HW_ACCESS_WSPI_INIT_CMD_MASK  0
  66
  67 /* HW limitation: maximum possible chunk size is 4095 bytes */
  68 #define WSPI_MAX_CHUNK_SIZE    4092
  69
  70 /* Maximum number of SPI write chunks */
  71 #define WSPI_MAX_NUM_OF_CHUNKS \
  72         ((WL1271_AGGR_BUFFER_SIZE / WSPI_MAX_CHUNK_SIZE) + 1)
  73
  74
  75 static inline struct spi_device *wl_to_spi(struct wl1271 *wl)
  76 {
  77         return wl->if_priv;
  78 }
  79
  80 static struct device *wl1271_spi_wl_to_dev(struct wl1271 *wl)
  81 {
  82         return &(wl_to_spi(wl)->dev);
  83 }
  84
  85 static void wl1271_spi_disable_interrupts(struct wl1271 *wl)
  86 {
  87         disable_irq(wl->irq);
  88 }
  89
  90 static void wl1271_spi_enable_interrupts(struct wl1271 *wl)
  91 {
  92         enable_irq(wl->irq);
  93 }
  94
  95 static void wl1271_spi_reset(struct wl1271 *wl)
  96 {
  97         u8 *cmd;
  98         struct spi_transfer t;
  99         struct spi_message m;
 100
 101         cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
 102         if (!cmd) {
 103                 wl1271_error("could not allocate cmd for spi reset");
 104                 return;
 105         }
 106
 107         memset(&t, 0, sizeof(t));
 108         spi_message_init(&m);
 109
 110         memset(cmd, 0xff, WSPI_INIT_CMD_LEN);
 111
 112         t.tx_buf = cmd;
 113         t.len = WSPI_INIT_CMD_LEN;
 114         spi_message_add_tail(&t, &m);
 115
 116         spi_sync(wl_to_spi(wl), &m);
 117
 118         wl1271_dump(DEBUG_SPI, "spi reset -> ", cmd, WSPI_INIT_CMD_LEN);
 119         kfree(cmd);
 120 }
 121
 122 static void wl1271_spi_init(struct wl1271 *wl)
 123 {
 124         u8 crc[WSPI_INIT_CMD_CRC_LEN], *cmd;
 125         struct spi_transfer t;
 126         struct spi_message m;
 127
 128         cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
 129         if (!cmd) {
 130                 wl1271_error("could not allocate cmd for spi init");
 131                 return;
 132         }
 133
 134         memset(crc, 0, sizeof(crc));
 135         memset(&t, 0, sizeof(t));
 136         spi_message_init(&m);
 137
 138         /*
 139          * Set WSPI_INIT_COMMAND
 140          * the data is being send from the MSB to LSB
 141          */
 142         cmd[2] = 0xff;
 143         cmd[3] = 0xff;
 144         cmd[1] = WSPI_INIT_CMD_START | WSPI_INIT_CMD_TX;
 145         cmd[0] = 0;
 146         cmd[7] = 0;
 147         cmd[6] |= HW_ACCESS_WSPI_INIT_CMD_MASK << 3;
 148         cmd[6] |= HW_ACCESS_WSPI_FIXED_BUSY_LEN & WSPI_INIT_CMD_FIXEDBUSY_LEN;
 149
 150         if (HW_ACCESS_WSPI_FIXED_BUSY_LEN == 0)
 151                 cmd[5] |=  WSPI_INIT_CMD_DIS_FIXEDBUSY;
 152         else
 153                 cmd[5] |= WSPI_INIT_CMD_EN_FIXEDBUSY;
 154
 155         cmd[5] |= WSPI_INIT_CMD_IOD | WSPI_INIT_CMD_IP | WSPI_INIT_CMD_CS
 156                 | WSPI_INIT_CMD_WSPI | WSPI_INIT_CMD_WS;
 157
 158         crc[0] = cmd[1];
 159         crc[1] = cmd[0];
 160         crc[2] = cmd[7];
 161         crc[3] = cmd[6];
 162         crc[4] = cmd[5];
 163
 164         cmd[4] |= crc7(0, crc, WSPI_INIT_CMD_CRC_LEN) << 1;
 165         cmd[4] |= WSPI_INIT_CMD_END;
 166
 167         t.tx_buf = cmd;
 168         t.len = WSPI_INIT_CMD_LEN;
 169         spi_message_add_tail(&t, &m);
 170
 171         spi_sync(wl_to_spi(wl), &m);
 172         wl1271_dump(DEBUG_SPI, "spi init -> ", cmd, WSPI_INIT_CMD_LEN);
 173         kfree(cmd);
 174 }
 175
 176 #define WL1271_BUSY_WORD_TIMEOUT 1000
 177
 178 static int wl1271_spi_read_busy(struct wl1271 *wl)
 179 {
 180         struct spi_transfer t[1];
 181         struct spi_message m;
 182         u32 *busy_buf;
 183         int num_busy_bytes = 0;
 184
 185         /*
 186          * Read further busy words from SPI until a non-busy word is
 187          * encountered, then read the data itself into the buffer.
 188          */
 189
 190         num_busy_bytes = WL1271_BUSY_WORD_TIMEOUT;
 191         busy_buf = wl->buffer_busyword;
 192         while (num_busy_bytes) {
 193                 num_busy_bytes--;
 194                 spi_message_init(&m);
 195                 memset(t, 0, sizeof(t));
 196                 t[0].rx_buf = busy_buf;
 197                 t[0].len = sizeof(u32);
 198                 t[0].cs_change = true;
 199                 spi_message_add_tail(&t[0], &m);
 200                 spi_sync(wl_to_spi(wl), &m);
 201
 202                 if (*busy_buf & 0x1)
 203                         return 0;
 204         }
 205
 206         /* The SPI bus is unresponsive, the read failed. */
 207         wl1271_error("SPI read busy-word timeout!\n");
 208         return -ETIMEDOUT;
 209 }
 210
 211 static void wl1271_spi_raw_read(struct wl1271 *wl, int addr, void *buf,
 212                                 size_t len, bool fixed)
 213 {
 214         struct spi_transfer t[2];
 215         struct spi_message m;
 216         u32 *busy_buf;
 217         u32 *cmd;
 218         u32 chunk_len;
 219
 220         while (len > 0) {
 221                 chunk_len = min((size_t)WSPI_MAX_CHUNK_SIZE, len);
 222
 223                 cmd = &wl->buffer_cmd;
 224                 busy_buf = wl->buffer_busyword;
 225
 226                 *cmd = 0;
 227                 *cmd |= WSPI_CMD_READ;
 228                 *cmd |= (chunk_len << WSPI_CMD_BYTE_LENGTH_OFFSET) &
 229                         WSPI_CMD_BYTE_LENGTH;
 230                 *cmd |= addr & WSPI_CMD_BYTE_ADDR;
 231
 232                 if (fixed)
 233                         *cmd |= WSPI_CMD_FIXED;
 234
 235                 spi_message_init(&m);
 236                 memset(t, 0, sizeof(t));
 237
 238                 t[0].tx_buf = cmd;
 239                 t[0].len = 4;
 240                 t[0].cs_change = true;
 241                 spi_message_add_tail(&t[0], &m);
 242
 243                 /* Busy and non busy words read */
 244                 t[1].rx_buf = busy_buf;
 245                 t[1].len = WL1271_BUSY_WORD_LEN;
 246                 t[1].cs_change = true;
 247                 spi_message_add_tail(&t[1], &m);
 248
 249                 spi_sync(wl_to_spi(wl), &m);
 250
 251                 if (!(busy_buf[WL1271_BUSY_WORD_CNT - 1] & 0x1) &&
 252                     wl1271_spi_read_busy(wl)) {
 253                         memset(buf, 0, chunk_len);
 254                         return;
 255                 }
 256
 257                 spi_message_init(&m);
 258                 memset(t, 0, sizeof(t));
 259
 260                 t[0].rx_buf = buf;
 261                 t[0].len = chunk_len;
 262                 t[0].cs_change = true;
 263                 spi_message_add_tail(&t[0], &m);
 264
 265                 spi_sync(wl_to_spi(wl), &m);
 266
 267                 wl1271_dump(DEBUG_SPI, "spi_read cmd -> ", cmd, sizeof(*cmd));
 268                 wl1271_dump(DEBUG_SPI, "spi_read buf <- ", buf, chunk_len);
 269
 270                 if (!fixed)
 271                         addr += chunk_len;
 272                 buf += chunk_len;
 273                 len -= chunk_len;
 274         }
 275 }
 276
 277 static void wl1271_spi_raw_write(struct wl1271 *wl, int addr, void *buf,
 278                           size_t len, bool fixed)
 279 {
 280         /* SPI write buffers - 2 for each chunk */
 281         struct spi_transfer t[2 * WSPI_MAX_NUM_OF_CHUNKS];
 282         struct spi_message m;
 283         u32 commands[WSPI_MAX_NUM_OF_CHUNKS]; /* 1 command per chunk */
 284         u32 *cmd;
 285         u32 chunk_len;
 286         int i;
 287
 288         WARN_ON(len > WL1271_AGGR_BUFFER_SIZE);
 289
 290         spi_message_init(&m);
 291         memset(t, 0, sizeof(t));
 292
 293         cmd = &commands[0];
 294         i = 0;
 295         while (len > 0) {
 296                 chunk_len = min((size_t)WSPI_MAX_CHUNK_SIZE, len);
 297
 298                 *cmd = 0;
 299                 *cmd |= WSPI_CMD_WRITE;
 300                 *cmd |= (chunk_len << WSPI_CMD_BYTE_LENGTH_OFFSET) &
 301                         WSPI_CMD_BYTE_LENGTH;
 302                 *cmd |= addr & WSPI_CMD_BYTE_ADDR;
 303
 304                 if (fixed)
 305                         *cmd |= WSPI_CMD_FIXED;
 306
 307                 t[i].tx_buf = cmd;
 308                 t[i].len = sizeof(*cmd);
 309                 spi_message_add_tail(&t[i++], &m);
 310
 311                 t[i].tx_buf = buf;
 312                 t[i].len = chunk_len;
 313                 spi_message_add_tail(&t[i++], &m);
 314
 315                 wl1271_dump(DEBUG_SPI, "spi_write cmd -> ", cmd, sizeof(*cmd));
 316                 wl1271_dump(DEBUG_SPI, "spi_write buf -> ", buf, chunk_len);
 317
 318                 if (!fixed)
 319                         addr += chunk_len;
 320                 buf += chunk_len;
 321                 len -= chunk_len;
 322                 cmd++;
 323         }
 324
 325         spi_sync(wl_to_spi(wl), &m);
 326 }
 327
 328 static irqreturn_t wl1271_hardirq(int irq, void *cookie)
 329 {
 330         struct wl1271 *wl = cookie;
 331         unsigned long flags;
 332
 333         wl1271_debug(DEBUG_IRQ, "IRQ");
 334
 335         /* complete the ELP completion */
 336         spin_lock_irqsave(&wl->wl_lock, flags);
 337         set_bit(WL1271_FLAG_IRQ_RUNNING, &wl->flags);
 338         if (wl->elp_compl) {
 339                 complete(wl->elp_compl);
 340                 wl->elp_compl = NULL;
 341         }
 342         spin_unlock_irqrestore(&wl->wl_lock, flags);
 343
 344         return IRQ_WAKE_THREAD;
 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         .set_block_size = NULL,
 365 };
 366
 367 static int __devinit wl1271_probe(struct spi_device *spi)
 368 {
 369         struct wl12xx_platform_data *pdata;
 370         struct ieee80211_hw *hw;
 371         struct wl1271 *wl;
 372         unsigned long irqflags;
 373         int ret;
 374
 375         pdata = spi->dev.platform_data;
 376         if (!pdata) {
 377                 wl1271_error("no platform data");
 378                 return -ENODEV;
 379         }
 380
 381         hw = wl1271_alloc_hw();
 382         if (IS_ERR(hw))
 383                 return PTR_ERR(hw);
 384
 385         wl = hw->priv;
 386
 387         dev_set_drvdata(&spi->dev, wl);
 388         wl->if_priv = spi;
 389
 390         wl->if_ops = &spi_ops;
 391
 392         /* This is the only SPI value that we need to set here, the rest
 393          * comes from the board-peripherals file */
 394         spi->bits_per_word = 32;
 395
 396         ret = spi_setup(spi);
 397         if (ret < 0) {
 398                 wl1271_error("spi_setup failed");
 399                 goto out_free;
 400         }
 401
 402         wl->set_power = pdata->set_power;
 403         if (!wl->set_power) {
 404                 wl1271_error("set power function missing in platform data");
 405                 ret = -ENODEV;
 406                 goto out_free;
 407         }
 408
 409         wl->ref_clock = pdata->board_ref_clock;
 410         wl->tcxo_clock = pdata->board_tcxo_clock;
 411         wl->platform_quirks = pdata->platform_quirks;
 412
 413         if (wl->platform_quirks & WL12XX_PLATFORM_QUIRK_EDGE_IRQ)
 414                 irqflags = IRQF_TRIGGER_RISING;
 415         else
 416                 irqflags = IRQF_TRIGGER_HIGH | IRQF_ONESHOT;
 417
 418         wl->irq = spi->irq;
 419         if (wl->irq < 0) {
 420                 wl1271_error("irq missing in platform data");
 421                 ret = -ENODEV;
 422                 goto out_free;
 423         }
 424
 425         ret = request_threaded_irq(wl->irq, wl1271_hardirq, wl1271_irq,
 426                                    irqflags,
 427                                    DRIVER_NAME, wl);
 428         if (ret < 0) {
 429                 wl1271_error("request_irq() failed: %d", ret);
 430                 goto out_free;
 431         }
 432
 433         disable_irq(wl->irq);
 434
 435         ret = wl1271_init_ieee80211(wl);
 436         if (ret)
 437                 goto out_irq;
 438
 439         ret = wl1271_register_hw(wl);
 440         if (ret)
 441                 goto out_irq;
 442
 443         return 0;
 444
 445  out_irq:
 446         free_irq(wl->irq, wl);
 447
 448  out_free:
 449         wl1271_free_hw(wl);
 450
 451         return ret;
 452 }
 453
 454 static int __devexit wl1271_remove(struct spi_device *spi)
 455 {
 456         struct wl1271 *wl = dev_get_drvdata(&spi->dev);
 457
 458         wl1271_unregister_hw(wl);
 459         free_irq(wl->irq, wl);
 460         wl1271_free_hw(wl);
 461
 462         return 0;
 463 }
 464
 465
 466 static struct spi_driver wl1271_spi_driver = {
 467         .driver = {
 468                 .name           = "wl1271_spi",
 469                 .bus            = &spi_bus_type,
 470                 .owner          = THIS_MODULE,
 471         },
 472
 473         .probe          = wl1271_probe,
 474         .remove         = __devexit_p(wl1271_remove),
 475 };
 476
 477 static int __init wl1271_init(void)
 478 {
 479         return spi_register_driver(&wl1271_spi_driver);
 480 }
 481
 482 static void __exit wl1271_exit(void)
 483 {
 484         spi_unregister_driver(&wl1271_spi_driver);
 485 }
 486
 487 module_init(wl1271_init);
 488 module_exit(wl1271_exit);
 489
 490 MODULE_LICENSE("GPL");
 491 MODULE_AUTHOR("Luciano Coelho <coelho@ti.com>");
 492 MODULE_AUTHOR("Juuso Oikarinen <juuso.oikarinen@nokia.com>");
 493 MODULE_FIRMWARE(WL127X_FW_NAME);
 494 MODULE_FIRMWARE(WL128X_FW_NAME);
 495 MODULE_ALIAS("spi:wl1271");