drivers/net/wireless/ti/wlcore/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/platform_device.h>
  31 #include <linux/slab.h>
  32
  33 #include "wlcore.h"
  34 #include "wl12xx_80211.h"
  35 #include "io.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 /*
  70  * only support SPI for 12xx - this code should be reworked when 18xx
  71  * support is introduced
  72  */
  73 #define SPI_AGGR_BUFFER_SIZE (4 * PAGE_SIZE)
  74
  75 #define WSPI_MAX_NUM_OF_CHUNKS (SPI_AGGR_BUFFER_SIZE / WSPI_MAX_CHUNK_SIZE)
  76
  77 struct wl12xx_spi_glue {
  78         struct device *dev;
  79         struct platform_device *core;
  80 };
  81
  82 static void wl12xx_spi_reset(struct device *child)
  83 {
  84         struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
  85         u8 *cmd;
  86         struct spi_transfer t;
  87         struct spi_message m;
  88
  89         cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
  90         if (!cmd) {
  91                 dev_err(child->parent,
  92                         "could not allocate cmd for spi reset\n");
  93                 return;
  94         }
  95
  96         memset(&t, 0, sizeof(t));
  97         spi_message_init(&m);
  98
  99         memset(cmd, 0xff, WSPI_INIT_CMD_LEN);
 100
 101         t.tx_buf = cmd;
 102         t.len = WSPI_INIT_CMD_LEN;
 103         spi_message_add_tail(&t, &m);
 104
 105         spi_sync(to_spi_device(glue->dev), &m);
 106
 107         kfree(cmd);
 108 }
 109
 110 static void wl12xx_spi_init(struct device *child)
 111 {
 112         struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
 113         u8 crc[WSPI_INIT_CMD_CRC_LEN], *cmd;
 114         struct spi_transfer t;
 115         struct spi_message m;
 116
 117         cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
 118         if (!cmd) {
 119                 dev_err(child->parent,
 120                         "could not allocate cmd for spi init\n");
 121                 return;
 122         }
 123
 124         memset(crc, 0, sizeof(crc));
 125         memset(&t, 0, sizeof(t));
 126         spi_message_init(&m);
 127
 128         /*
 129          * Set WSPI_INIT_COMMAND
 130          * the data is being send from the MSB to LSB
 131          */
 132         cmd[2] = 0xff;
 133         cmd[3] = 0xff;
 134         cmd[1] = WSPI_INIT_CMD_START | WSPI_INIT_CMD_TX;
 135         cmd[0] = 0;
 136         cmd[7] = 0;
 137         cmd[6] |= HW_ACCESS_WSPI_INIT_CMD_MASK << 3;
 138         cmd[6] |= HW_ACCESS_WSPI_FIXED_BUSY_LEN & WSPI_INIT_CMD_FIXEDBUSY_LEN;
 139
 140         if (HW_ACCESS_WSPI_FIXED_BUSY_LEN == 0)
 141                 cmd[5] |=  WSPI_INIT_CMD_DIS_FIXEDBUSY;
 142         else
 143                 cmd[5] |= WSPI_INIT_CMD_EN_FIXEDBUSY;
 144
 145         cmd[5] |= WSPI_INIT_CMD_IOD | WSPI_INIT_CMD_IP | WSPI_INIT_CMD_CS
 146                 | WSPI_INIT_CMD_WSPI | WSPI_INIT_CMD_WS;
 147
 148         crc[0] = cmd[1];
 149         crc[1] = cmd[0];
 150         crc[2] = cmd[7];
 151         crc[3] = cmd[6];
 152         crc[4] = cmd[5];
 153
 154         cmd[4] |= crc7(0, crc, WSPI_INIT_CMD_CRC_LEN) << 1;
 155         cmd[4] |= WSPI_INIT_CMD_END;
 156
 157         t.tx_buf = cmd;
 158         t.len = WSPI_INIT_CMD_LEN;
 159         spi_message_add_tail(&t, &m);
 160
 161         spi_sync(to_spi_device(glue->dev), &m);
 162         kfree(cmd);
 163 }
 164
 165 #define WL1271_BUSY_WORD_TIMEOUT 1000
 166
 167 static int wl12xx_spi_read_busy(struct device *child)
 168 {
 169         struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
 170         struct wl1271 *wl = dev_get_drvdata(child);
 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(to_spi_device(glue->dev), &m);
 192
 193                 if (*busy_buf & 0x1)
 194                         return 0;
 195         }
 196
 197         /* The SPI bus is unresponsive, the read failed. */
 198         dev_err(child->parent, "SPI read busy-word timeout!\n");
 199         return -ETIMEDOUT;
 200 }
 201
 202 static int __must_check wl12xx_spi_raw_read(struct device *child, int addr,
 203                                             void *buf, size_t len, bool fixed)
 204 {
 205         struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
 206         struct wl1271 *wl = dev_get_drvdata(child);
 207         struct spi_transfer t[2];
 208         struct spi_message m;
 209         u32 *busy_buf;
 210         u32 *cmd;
 211         u32 chunk_len;
 212
 213         while (len > 0) {
 214                 chunk_len = min((size_t)WSPI_MAX_CHUNK_SIZE, len);
 215
 216                 cmd = &wl->buffer_cmd;
 217                 busy_buf = wl->buffer_busyword;
 218
 219                 *cmd = 0;
 220                 *cmd |= WSPI_CMD_READ;
 221                 *cmd |= (chunk_len << WSPI_CMD_BYTE_LENGTH_OFFSET) &
 222                         WSPI_CMD_BYTE_LENGTH;
 223                 *cmd |= addr & WSPI_CMD_BYTE_ADDR;
 224
 225                 if (fixed)
 226                         *cmd |= WSPI_CMD_FIXED;
 227
 228                 spi_message_init(&m);
 229                 memset(t, 0, sizeof(t));
 230
 231                 t[0].tx_buf = cmd;
 232                 t[0].len = 4;
 233                 t[0].cs_change = true;
 234                 spi_message_add_tail(&t[0], &m);
 235
 236                 /* Busy and non busy words read */
 237                 t[1].rx_buf = busy_buf;
 238                 t[1].len = WL1271_BUSY_WORD_LEN;
 239                 t[1].cs_change = true;
 240                 spi_message_add_tail(&t[1], &m);
 241
 242                 spi_sync(to_spi_device(glue->dev), &m);
 243
 244                 if (!(busy_buf[WL1271_BUSY_WORD_CNT - 1] & 0x1) &&
 245                     wl12xx_spi_read_busy(child)) {
 246                         memset(buf, 0, chunk_len);
 247                         return 0;
 248                 }
 249
 250                 spi_message_init(&m);
 251                 memset(t, 0, sizeof(t));
 252
 253                 t[0].rx_buf = buf;
 254                 t[0].len = chunk_len;
 255                 t[0].cs_change = true;
 256                 spi_message_add_tail(&t[0], &m);
 257
 258                 spi_sync(to_spi_device(glue->dev), &m);
 259
 260                 if (!fixed)
 261                         addr += chunk_len;
 262                 buf += chunk_len;
 263                 len -= chunk_len;
 264         }
 265
 266         return 0;
 267 }
 268
 269 static int __must_check wl12xx_spi_raw_write(struct device *child, int addr,
 270                                              void *buf, size_t len, bool fixed)
 271 {
 272         struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
 273         struct spi_transfer t[2 * (WSPI_MAX_NUM_OF_CHUNKS + 1)];
 274         struct spi_message m;
 275         u32 commands[WSPI_MAX_NUM_OF_CHUNKS];
 276         u32 *cmd;
 277         u32 chunk_len;
 278         int i;
 279
 280         WARN_ON(len > SPI_AGGR_BUFFER_SIZE);
 281
 282         spi_message_init(&m);
 283         memset(t, 0, sizeof(t));
 284
 285         cmd = &commands[0];
 286         i = 0;
 287         while (len > 0) {
 288                 chunk_len = min((size_t)WSPI_MAX_CHUNK_SIZE, len);
 289
 290                 *cmd = 0;
 291                 *cmd |= WSPI_CMD_WRITE;
 292                 *cmd |= (chunk_len << WSPI_CMD_BYTE_LENGTH_OFFSET) &
 293                         WSPI_CMD_BYTE_LENGTH;
 294                 *cmd |= addr & WSPI_CMD_BYTE_ADDR;
 295
 296                 if (fixed)
 297                         *cmd |= WSPI_CMD_FIXED;
 298
 299                 t[i].tx_buf = cmd;
 300                 t[i].len = sizeof(*cmd);
 301                 spi_message_add_tail(&t[i++], &m);
 302
 303                 t[i].tx_buf = buf;
 304                 t[i].len = chunk_len;
 305                 spi_message_add_tail(&t[i++], &m);
 306
 307                 if (!fixed)
 308                         addr += chunk_len;
 309                 buf += chunk_len;
 310                 len -= chunk_len;
 311                 cmd++;
 312         }
 313
 314         spi_sync(to_spi_device(glue->dev), &m);
 315
 316         return 0;
 317 }
 318
 319 static struct wl1271_if_operations spi_ops = {
 320         .read           = wl12xx_spi_raw_read,
 321         .write          = wl12xx_spi_raw_write,
 322         .reset          = wl12xx_spi_reset,
 323         .init           = wl12xx_spi_init,
 324         .set_block_size = NULL,
 325 };
 326
 327 static int wl1271_probe(struct spi_device *spi)
 328 {
 329         struct wl12xx_spi_glue *glue;
 330         struct wl12xx_platform_data *pdata;
 331         struct resource res[1];
 332         int ret = -ENOMEM;
 333
 334         pdata = spi->dev.platform_data;
 335         if (!pdata) {
 336                 dev_err(&spi->dev, "no platform data\n");
 337                 return -ENODEV;
 338         }
 339
 340         pdata->ops = &spi_ops;
 341
 342         glue = kzalloc(sizeof(*glue), GFP_KERNEL);
 343         if (!glue) {
 344                 dev_err(&spi->dev, "can't allocate glue\n");
 345                 goto out;
 346         }
 347
 348         glue->dev = &spi->dev;
 349
 350         spi_set_drvdata(spi, glue);
 351
 352         /* This is the only SPI value that we need to set here, the rest
 353          * comes from the board-peripherals file */
 354         spi->bits_per_word = 32;
 355
 356         ret = spi_setup(spi);
 357         if (ret < 0) {
 358                 dev_err(glue->dev, "spi_setup failed\n");
 359                 goto out_free_glue;
 360         }
 361
 362         glue->core = platform_device_alloc("wl12xx", -1);
 363         if (!glue->core) {
 364                 dev_err(glue->dev, "can't allocate platform_device\n");
 365                 ret = -ENOMEM;
 366                 goto out_free_glue;
 367         }
 368
 369         glue->core->dev.parent = &spi->dev;
 370
 371         memset(res, 0x00, sizeof(res));
 372
 373         res[0].start = spi->irq;
 374         res[0].flags = IORESOURCE_IRQ;
 375         res[0].name = "irq";
 376
 377         ret = platform_device_add_resources(glue->core, res, ARRAY_SIZE(res));
 378         if (ret) {
 379                 dev_err(glue->dev, "can't add resources\n");
 380                 goto out_dev_put;
 381         }
 382
 383         ret = platform_device_add_data(glue->core, pdata, sizeof(*pdata));
 384         if (ret) {
 385                 dev_err(glue->dev, "can't add platform data\n");
 386                 goto out_dev_put;
 387         }
 388
 389         ret = platform_device_add(glue->core);
 390         if (ret) {
 391                 dev_err(glue->dev, "can't register platform device\n");
 392                 goto out_dev_put;
 393         }
 394
 395         return 0;
 396
 397 out_dev_put:
 398         platform_device_put(glue->core);
 399
 400 out_free_glue:
 401         kfree(glue);
 402 out:
 403         return ret;
 404 }
 405
 406 static int wl1271_remove(struct spi_device *spi)
 407 {
 408         struct wl12xx_spi_glue *glue = spi_get_drvdata(spi);
 409
 410         platform_device_unregister(glue->core);
 411         kfree(glue);
 412
 413         return 0;
 414 }
 415
 416
 417 static struct spi_driver wl1271_spi_driver = {
 418         .driver = {
 419                 .name           = "wl1271_spi",
 420                 .owner          = THIS_MODULE,
 421         },
 422
 423         .probe          = wl1271_probe,
 424         .remove         = wl1271_remove,
 425 };
 426
 427 static int __init wl1271_init(void)
 428 {
 429         return spi_register_driver(&wl1271_spi_driver);
 430 }
 431
 432 static void __exit wl1271_exit(void)
 433 {
 434         spi_unregister_driver(&wl1271_spi_driver);
 435 }
 436
 437 module_init(wl1271_init);
 438 module_exit(wl1271_exit);
 439
 440 MODULE_LICENSE("GPL");
 441 MODULE_AUTHOR("Luciano Coelho <coelho@ti.com>");
 442 MODULE_AUTHOR("Juuso Oikarinen <juuso.oikarinen@nokia.com>");
 443 MODULE_ALIAS("spi:wl1271");