drivers/net/wireless/wl12xx/wl1271_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 "wl1271.h"
  32 #include "wl12xx_80211.h"
  33 #include "wl1271_io.h"
  34
  35 #include "wl1271_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 static inline struct spi_device *wl_to_spi(struct wl1271 *wl)
  67 {
  68         return wl->if_priv;
  69 }
  70
  71 static struct device *wl1271_spi_wl_to_dev(struct wl1271 *wl)
  72 {
  73         return &(wl_to_spi(wl)->dev);
  74 }
  75
  76 static void wl1271_spi_disable_interrupts(struct wl1271 *wl)
  77 {
  78         disable_irq(wl->irq);
  79 }
  80
  81 static void wl1271_spi_enable_interrupts(struct wl1271 *wl)
  82 {
  83         enable_irq(wl->irq);
  84 }
  85
  86 static void wl1271_spi_reset(struct wl1271 *wl)
  87 {
  88         u8 *cmd;
  89         struct spi_transfer t;
  90         struct spi_message m;
  91
  92         cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
  93         if (!cmd) {
  94                 wl1271_error("could not allocate cmd for spi reset");
  95                 return;
  96         }
  97
  98         memset(&t, 0, sizeof(t));
  99         spi_message_init(&m);
 100
 101         memset(cmd, 0xff, WSPI_INIT_CMD_LEN);
 102
 103         t.tx_buf = cmd;
 104         t.len = WSPI_INIT_CMD_LEN;
 105         spi_message_add_tail(&t, &m);
 106
 107         spi_sync(wl_to_spi(wl), &m);
 108         kfree(cmd);
 109
 110         wl1271_dump(DEBUG_SPI, "spi reset -> ", cmd, WSPI_INIT_CMD_LEN);
 111 }
 112
 113 static void wl1271_spi_init(struct wl1271 *wl)
 114 {
 115         u8 crc[WSPI_INIT_CMD_CRC_LEN], *cmd;
 116         struct spi_transfer t;
 117         struct spi_message m;
 118
 119         cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
 120         if (!cmd) {
 121                 wl1271_error("could not allocate cmd for spi init");
 122                 return;
 123         }
 124
 125         memset(crc, 0, sizeof(crc));
 126         memset(&t, 0, sizeof(t));
 127         spi_message_init(&m);
 128
 129         /*
 130          * Set WSPI_INIT_COMMAND
 131          * the data is being send from the MSB to LSB
 132          */
 133         cmd[2] = 0xff;
 134         cmd[3] = 0xff;
 135         cmd[1] = WSPI_INIT_CMD_START | WSPI_INIT_CMD_TX;
 136         cmd[0] = 0;
 137         cmd[7] = 0;
 138         cmd[6] |= HW_ACCESS_WSPI_INIT_CMD_MASK << 3;
 139         cmd[6] |= HW_ACCESS_WSPI_FIXED_BUSY_LEN & WSPI_INIT_CMD_FIXEDBUSY_LEN;
 140
 141         if (HW_ACCESS_WSPI_FIXED_BUSY_LEN == 0)
 142                 cmd[5] |=  WSPI_INIT_CMD_DIS_FIXEDBUSY;
 143         else
 144                 cmd[5] |= WSPI_INIT_CMD_EN_FIXEDBUSY;
 145
 146         cmd[5] |= WSPI_INIT_CMD_IOD | WSPI_INIT_CMD_IP | WSPI_INIT_CMD_CS
 147                 | WSPI_INIT_CMD_WSPI | WSPI_INIT_CMD_WS;
 148
 149         crc[0] = cmd[1];
 150         crc[1] = cmd[0];
 151         crc[2] = cmd[7];
 152         crc[3] = cmd[6];
 153         crc[4] = cmd[5];
 154
 155         cmd[4] |= crc7(0, crc, WSPI_INIT_CMD_CRC_LEN) << 1;
 156         cmd[4] |= WSPI_INIT_CMD_END;
 157
 158         t.tx_buf = cmd;
 159         t.len = WSPI_INIT_CMD_LEN;
 160         spi_message_add_tail(&t, &m);
 161
 162         spi_sync(wl_to_spi(wl), &m);
 163         wl1271_dump(DEBUG_SPI, "spi init -> ", cmd, WSPI_INIT_CMD_LEN);
 164         kfree(cmd);
 165 }
 166
 167 #define WL1271_BUSY_WORD_TIMEOUT 1000
 168
 169 static int wl1271_spi_read_busy(struct wl1271 *wl)
 170 {
 171         struct spi_transfer t[1];
 172         struct spi_message m;
 173         u32 *busy_buf;
 174         int num_busy_bytes = 0;
 175
 176         /*
 177          * Read further busy words from SPI until a non-busy word is
 178          * encountered, then read the data itself into the buffer.
 179          */
 180
 181         num_busy_bytes = WL1271_BUSY_WORD_TIMEOUT;
 182         busy_buf = wl->buffer_busyword;
 183         while (num_busy_bytes) {
 184                 num_busy_bytes--;
 185                 spi_message_init(&m);
 186                 memset(t, 0, sizeof(t));
 187                 t[0].rx_buf = busy_buf;
 188                 t[0].len = sizeof(u32);
 189                 t[0].cs_change = true;
 190                 spi_message_add_tail(&t[0], &m);
 191                 spi_sync(wl_to_spi(wl), &m);
 192
 193                 if (*busy_buf & 0x1)
 194                         return 0;
 195         }
 196
 197         /* The SPI bus is unresponsive, the read failed. */
 198         wl1271_error("SPI read busy-word timeout!\n");
 199         return -ETIMEDOUT;
 200 }
 201
 202 static void wl1271_spi_raw_read(struct wl1271 *wl, int addr, void *buf,
 203                                 size_t len, bool fixed)
 204 {
 205         struct spi_transfer t[3];
 206         struct spi_message m;
 207         u32 *busy_buf;
 208         u32 *cmd;
 209
 210         cmd = &wl->buffer_cmd;
 211         busy_buf = wl->buffer_busyword;
 212
 213         *cmd = 0;
 214         *cmd |= WSPI_CMD_READ;
 215         *cmd |= (len << WSPI_CMD_BYTE_LENGTH_OFFSET) & WSPI_CMD_BYTE_LENGTH;
 216         *cmd |= addr & WSPI_CMD_BYTE_ADDR;
 217
 218         if (fixed)
 219                 *cmd |= WSPI_CMD_FIXED;
 220
 221         spi_message_init(&m);
 222         memset(t, 0, sizeof(t));
 223
 224         t[0].tx_buf = cmd;
 225         t[0].len = 4;
 226         t[0].cs_change = true;
 227         spi_message_add_tail(&t[0], &m);
 228
 229         /* Busy and non busy words read */
 230         t[1].rx_buf = busy_buf;
 231         t[1].len = WL1271_BUSY_WORD_LEN;
 232         t[1].cs_change = true;
 233         spi_message_add_tail(&t[1], &m);
 234
 235         spi_sync(wl_to_spi(wl), &m);
 236
 237         if (!(busy_buf[WL1271_BUSY_WORD_CNT - 1] & 0x1) &&
 238             wl1271_spi_read_busy(wl)) {
 239                 memset(buf, 0, len);
 240                 return;
 241         }
 242
 243         spi_message_init(&m);
 244         memset(t, 0, sizeof(t));
 245
 246         t[0].rx_buf = buf;
 247         t[0].len = len;
 248         t[0].cs_change = true;
 249         spi_message_add_tail(&t[0], &m);
 250
 251         spi_sync(wl_to_spi(wl), &m);
 252
 253         wl1271_dump(DEBUG_SPI, "spi_read cmd -> ", cmd, sizeof(*cmd));
 254         wl1271_dump(DEBUG_SPI, "spi_read buf <- ", buf, len);
 255 }
 256
 257 static void wl1271_spi_raw_write(struct wl1271 *wl, int addr, void *buf,
 258                           size_t len, bool fixed)
 259 {
 260         struct spi_transfer t[2];
 261         struct spi_message m;
 262         u32 *cmd;
 263
 264         cmd = &wl->buffer_cmd;
 265
 266         *cmd = 0;
 267         *cmd |= WSPI_CMD_WRITE;
 268         *cmd |= (len << WSPI_CMD_BYTE_LENGTH_OFFSET) & WSPI_CMD_BYTE_LENGTH;
 269         *cmd |= addr & WSPI_CMD_BYTE_ADDR;
 270
 271         if (fixed)
 272                 *cmd |= WSPI_CMD_FIXED;
 273
 274         spi_message_init(&m);
 275         memset(t, 0, sizeof(t));
 276
 277         t[0].tx_buf = cmd;
 278         t[0].len = sizeof(*cmd);
 279         spi_message_add_tail(&t[0], &m);
 280
 281         t[1].tx_buf = buf;
 282         t[1].len = len;
 283         spi_message_add_tail(&t[1], &m);
 284
 285         spi_sync(wl_to_spi(wl), &m);
 286
 287         wl1271_dump(DEBUG_SPI, "spi_write cmd -> ", cmd, sizeof(*cmd));
 288         wl1271_dump(DEBUG_SPI, "spi_write buf -> ", buf, len);
 289 }
 290
 291 static irqreturn_t wl1271_irq(int irq, void *cookie)
 292 {
 293         struct wl1271 *wl;
 294         unsigned long flags;
 295
 296         wl1271_debug(DEBUG_IRQ, "IRQ");
 297
 298         wl = cookie;
 299
 300         /* complete the ELP completion */
 301         spin_lock_irqsave(&wl->wl_lock, flags);
 302         if (wl->elp_compl) {
 303                 complete(wl->elp_compl);
 304                 wl->elp_compl = NULL;
 305         }
 306
 307         if (!test_and_set_bit(WL1271_FLAG_IRQ_RUNNING, &wl->flags))
 308                 ieee80211_queue_work(wl->hw, &wl->irq_work);
 309         set_bit(WL1271_FLAG_IRQ_PENDING, &wl->flags);
 310         spin_unlock_irqrestore(&wl->wl_lock, flags);
 311
 312         return IRQ_HANDLED;
 313 }
 314
 315 static int wl1271_spi_set_power(struct wl1271 *wl, bool enable)
 316 {
 317         if (wl->set_power)
 318                 wl->set_power(enable);
 319
 320         return 0;
 321 }
 322
 323 static struct wl1271_if_operations spi_ops = {
 324         .read           = wl1271_spi_raw_read,
 325         .write          = wl1271_spi_raw_write,
 326         .reset          = wl1271_spi_reset,
 327         .init           = wl1271_spi_init,
 328         .power          = wl1271_spi_set_power,
 329         .dev            = wl1271_spi_wl_to_dev,
 330         .enable_irq     = wl1271_spi_enable_interrupts,
 331         .disable_irq    = wl1271_spi_disable_interrupts
 332 };
 333
 334 static int __devinit wl1271_probe(struct spi_device *spi)
 335 {
 336         struct wl12xx_platform_data *pdata;
 337         struct ieee80211_hw *hw;
 338         struct wl1271 *wl;
 339         int ret;
 340
 341         pdata = spi->dev.platform_data;
 342         if (!pdata) {
 343                 wl1271_error("no platform data");
 344                 return -ENODEV;
 345         }
 346
 347         hw = wl1271_alloc_hw();
 348         if (IS_ERR(hw))
 349                 return PTR_ERR(hw);
 350
 351         wl = hw->priv;
 352
 353         dev_set_drvdata(&spi->dev, wl);
 354         wl->if_priv = spi;
 355
 356         wl->if_ops = &spi_ops;
 357
 358         /* This is the only SPI value that we need to set here, the rest
 359          * comes from the board-peripherals file */
 360         spi->bits_per_word = 32;
 361
 362         ret = spi_setup(spi);
 363         if (ret < 0) {
 364                 wl1271_error("spi_setup failed");
 365                 goto out_free;
 366         }
 367
 368         wl->set_power = pdata->set_power;
 369         if (!wl->set_power) {
 370                 wl1271_error("set power function missing in platform data");
 371                 ret = -ENODEV;
 372                 goto out_free;
 373         }
 374
 375         wl->ref_clock = pdata->board_ref_clock;
 376
 377         wl->irq = spi->irq;
 378         if (wl->irq < 0) {
 379                 wl1271_error("irq missing in platform data");
 380                 ret = -ENODEV;
 381                 goto out_free;
 382         }
 383
 384         ret = request_irq(wl->irq, wl1271_irq, 0, DRIVER_NAME, wl);
 385         if (ret < 0) {
 386                 wl1271_error("request_irq() failed: %d", ret);
 387                 goto out_free;
 388         }
 389
 390         set_irq_type(wl->irq, IRQ_TYPE_EDGE_RISING);
 391
 392         disable_irq(wl->irq);
 393
 394         ret = wl1271_init_ieee80211(wl);
 395         if (ret)
 396                 goto out_irq;
 397
 398         ret = wl1271_register_hw(wl);
 399         if (ret)
 400                 goto out_irq;
 401
 402         wl1271_notice("initialized");
 403
 404         return 0;
 405
 406  out_irq:
 407         free_irq(wl->irq, wl);
 408
 409  out_free:
 410         wl1271_free_hw(wl);
 411
 412         return ret;
 413 }
 414
 415 static int __devexit wl1271_remove(struct spi_device *spi)
 416 {
 417         struct wl1271 *wl = dev_get_drvdata(&spi->dev);
 418
 419         wl1271_unregister_hw(wl);
 420         free_irq(wl->irq, wl);
 421         wl1271_free_hw(wl);
 422
 423         return 0;
 424 }
 425
 426
 427 static struct spi_driver wl1271_spi_driver = {
 428         .driver = {
 429                 .name           = "wl1271_spi",
 430                 .bus            = &spi_bus_type,
 431                 .owner          = THIS_MODULE,
 432         },
 433
 434         .probe          = wl1271_probe,
 435         .remove         = __devexit_p(wl1271_remove),
 436 };
 437
 438 static int __init wl1271_init(void)
 439 {
 440         int ret;
 441
 442         ret = spi_register_driver(&wl1271_spi_driver);
 443         if (ret < 0) {
 444                 wl1271_error("failed to register spi driver: %d", ret);
 445                 goto out;
 446         }
 447
 448 out:
 449         return ret;
 450 }
 451
 452 static void __exit wl1271_exit(void)
 453 {
 454         spi_unregister_driver(&wl1271_spi_driver);
 455
 456         wl1271_notice("unloaded");
 457 }
 458
 459 module_init(wl1271_init);
 460 module_exit(wl1271_exit);
 461
 462 MODULE_LICENSE("GPL");
 463 MODULE_AUTHOR("Luciano Coelho <luciano.coelho@nokia.com>");
 464 MODULE_AUTHOR("Juuso Oikarinen <juuso.oikarinen@nokia.com>");
 465 MODULE_FIRMWARE(WL1271_FW_NAME);
 466 MODULE_ALIAS("spi:wl1271");