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                 return;
  92
  93         memset(&t, 0, sizeof(t));
  94         spi_message_init(&m);
  95
  96         memset(cmd, 0xff, WSPI_INIT_CMD_LEN);
  97
  98         t.tx_buf = cmd;
  99         t.len = WSPI_INIT_CMD_LEN;
 100         spi_message_add_tail(&t, &m);
 101
 102         spi_sync(to_spi_device(glue->dev), &m);
 103
 104         kfree(cmd);
 105 }
 106
 107 static void wl12xx_spi_init(struct device *child)
 108 {
 109         struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
 110         u8 crc[WSPI_INIT_CMD_CRC_LEN], *cmd;
 111         struct spi_transfer t;
 112         struct spi_message m;
 113
 114         cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
 115         if (!cmd)
 116                 return;
 117
 118         memset(crc, 0, sizeof(crc));
 119         memset(&t, 0, sizeof(t));
 120         spi_message_init(&m);
 121
 122         /*
 123          * Set WSPI_INIT_COMMAND
 124          * the data is being send from the MSB to LSB
 125          */
 126         cmd[2] = 0xff;
 127         cmd[3] = 0xff;
 128         cmd[1] = WSPI_INIT_CMD_START | WSPI_INIT_CMD_TX;
 129         cmd[0] = 0;
 130         cmd[7] = 0;
 131         cmd[6] |= HW_ACCESS_WSPI_INIT_CMD_MASK << 3;
 132         cmd[6] |= HW_ACCESS_WSPI_FIXED_BUSY_LEN & WSPI_INIT_CMD_FIXEDBUSY_LEN;
 133
 134         if (HW_ACCESS_WSPI_FIXED_BUSY_LEN == 0)
 135                 cmd[5] |=  WSPI_INIT_CMD_DIS_FIXEDBUSY;
 136         else
 137                 cmd[5] |= WSPI_INIT_CMD_EN_FIXEDBUSY;
 138
 139         cmd[5] |= WSPI_INIT_CMD_IOD | WSPI_INIT_CMD_IP | WSPI_INIT_CMD_CS
 140                 | WSPI_INIT_CMD_WSPI | WSPI_INIT_CMD_WS;
 141
 142         crc[0] = cmd[1];
 143         crc[1] = cmd[0];
 144         crc[2] = cmd[7];
 145         crc[3] = cmd[6];
 146         crc[4] = cmd[5];
 147
 148         cmd[4] |= crc7(0, crc, WSPI_INIT_CMD_CRC_LEN) << 1;
 149         cmd[4] |= WSPI_INIT_CMD_END;
 150
 151         t.tx_buf = cmd;
 152         t.len = WSPI_INIT_CMD_LEN;
 153         spi_message_add_tail(&t, &m);
 154
 155         spi_sync(to_spi_device(glue->dev), &m);
 156         kfree(cmd);
 157 }
 158
 159 #define WL1271_BUSY_WORD_TIMEOUT 1000
 160
 161 static int wl12xx_spi_read_busy(struct device *child)
 162 {
 163         struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
 164         struct wl1271 *wl = dev_get_drvdata(child);
 165         struct spi_transfer t[1];
 166         struct spi_message m;
 167         u32 *busy_buf;
 168         int num_busy_bytes = 0;
 169
 170         /*
 171          * Read further busy words from SPI until a non-busy word is
 172          * encountered, then read the data itself into the buffer.
 173          */
 174
 175         num_busy_bytes = WL1271_BUSY_WORD_TIMEOUT;
 176         busy_buf = wl->buffer_busyword;
 177         while (num_busy_bytes) {
 178                 num_busy_bytes--;
 179                 spi_message_init(&m);
 180                 memset(t, 0, sizeof(t));
 181                 t[0].rx_buf = busy_buf;
 182                 t[0].len = sizeof(u32);
 183                 t[0].cs_change = true;
 184                 spi_message_add_tail(&t[0], &m);
 185                 spi_sync(to_spi_device(glue->dev), &m);
 186
 187                 if (*busy_buf & 0x1)
 188                         return 0;
 189         }
 190
 191         /* The SPI bus is unresponsive, the read failed. */
 192         dev_err(child->parent, "SPI read busy-word timeout!\n");
 193         return -ETIMEDOUT;
 194 }
 195
 196 static int __must_check wl12xx_spi_raw_read(struct device *child, int addr,
 197                                             void *buf, size_t len, bool fixed)
 198 {
 199         struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
 200         struct wl1271 *wl = dev_get_drvdata(child);
 201         struct spi_transfer t[2];
 202         struct spi_message m;
 203         u32 *busy_buf;
 204         u32 *cmd;
 205         u32 chunk_len;
 206
 207         while (len > 0) {
 208                 chunk_len = min((size_t)WSPI_MAX_CHUNK_SIZE, len);
 209
 210                 cmd = &wl->buffer_cmd;
 211                 busy_buf = wl->buffer_busyword;
 212
 213                 *cmd = 0;
 214                 *cmd |= WSPI_CMD_READ;
 215                 *cmd |= (chunk_len << WSPI_CMD_BYTE_LENGTH_OFFSET) &
 216                         WSPI_CMD_BYTE_LENGTH;
 217                 *cmd |= addr & WSPI_CMD_BYTE_ADDR;
 218
 219                 if (fixed)
 220                         *cmd |= WSPI_CMD_FIXED;
 221
 222                 spi_message_init(&m);
 223                 memset(t, 0, sizeof(t));
 224
 225                 t[0].tx_buf = cmd;
 226                 t[0].len = 4;
 227                 t[0].cs_change = true;
 228                 spi_message_add_tail(&t[0], &m);
 229
 230                 /* Busy and non busy words read */
 231                 t[1].rx_buf = busy_buf;
 232                 t[1].len = WL1271_BUSY_WORD_LEN;
 233                 t[1].cs_change = true;
 234                 spi_message_add_tail(&t[1], &m);
 235
 236                 spi_sync(to_spi_device(glue->dev), &m);
 237
 238                 if (!(busy_buf[WL1271_BUSY_WORD_CNT - 1] & 0x1) &&
 239                     wl12xx_spi_read_busy(child)) {
 240                         memset(buf, 0, chunk_len);
 241                         return 0;
 242                 }
 243
 244                 spi_message_init(&m);
 245                 memset(t, 0, sizeof(t));
 246
 247                 t[0].rx_buf = buf;
 248                 t[0].len = chunk_len;
 249                 t[0].cs_change = true;
 250                 spi_message_add_tail(&t[0], &m);
 251
 252                 spi_sync(to_spi_device(glue->dev), &m);
 253
 254                 if (!fixed)
 255                         addr += chunk_len;
 256                 buf += chunk_len;
 257                 len -= chunk_len;
 258         }
 259
 260         return 0;
 261 }
 262
 263 static int __must_check wl12xx_spi_raw_write(struct device *child, int addr,
 264                                              void *buf, size_t len, bool fixed)
 265 {
 266         struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
 267         struct spi_transfer t[2 * WSPI_MAX_NUM_OF_CHUNKS];
 268         struct spi_message m;
 269         u32 commands[WSPI_MAX_NUM_OF_CHUNKS];
 270         u32 *cmd;
 271         u32 chunk_len;
 272         int i;
 273
 274         WARN_ON(len > SPI_AGGR_BUFFER_SIZE);
 275
 276         spi_message_init(&m);
 277         memset(t, 0, sizeof(t));
 278
 279         cmd = &commands[0];
 280         i = 0;
 281         while (len > 0) {
 282                 chunk_len = min((size_t)WSPI_MAX_CHUNK_SIZE, len);
 283
 284                 *cmd = 0;
 285                 *cmd |= WSPI_CMD_WRITE;
 286                 *cmd |= (chunk_len << WSPI_CMD_BYTE_LENGTH_OFFSET) &
 287                         WSPI_CMD_BYTE_LENGTH;
 288                 *cmd |= addr & WSPI_CMD_BYTE_ADDR;
 289
 290                 if (fixed)
 291                         *cmd |= WSPI_CMD_FIXED;
 292
 293                 t[i].tx_buf = cmd;
 294                 t[i].len = sizeof(*cmd);
 295                 spi_message_add_tail(&t[i++], &m);
 296
 297                 t[i].tx_buf = buf;
 298                 t[i].len = chunk_len;
 299                 spi_message_add_tail(&t[i++], &m);
 300
 301                 if (!fixed)
 302                         addr += chunk_len;
 303                 buf += chunk_len;
 304                 len -= chunk_len;
 305                 cmd++;
 306         }
 307
 308         spi_sync(to_spi_device(glue->dev), &m);
 309
 310         return 0;
 311 }
 312
 313 static struct wl1271_if_operations spi_ops = {
 314         .read           = wl12xx_spi_raw_read,
 315         .write          = wl12xx_spi_raw_write,
 316         .reset          = wl12xx_spi_reset,
 317         .init           = wl12xx_spi_init,
 318         .set_block_size = NULL,
 319 };
 320
 321 static int wl1271_probe(struct spi_device *spi)
 322 {
 323         struct wl12xx_spi_glue *glue;
 324         struct wl12xx_platform_data *pdata;
 325         struct resource res[1];
 326         int ret = -ENOMEM;
 327
 328         pdata = spi->dev.platform_data;
 329         if (!pdata) {
 330                 dev_err(&spi->dev, "no platform data\n");
 331                 return -ENODEV;
 332         }
 333
 334         pdata->ops = &spi_ops;
 335
 336         glue = kzalloc(sizeof(*glue), GFP_KERNEL);
 337         if (!glue)
 338                 goto out;
 339
 340         glue->dev = &spi->dev;
 341
 342         spi_set_drvdata(spi, glue);
 343
 344         /* This is the only SPI value that we need to set here, the rest
 345          * comes from the board-peripherals file */
 346         spi->bits_per_word = 32;
 347
 348         ret = spi_setup(spi);
 349         if (ret < 0) {
 350                 dev_err(glue->dev, "spi_setup failed\n");
 351                 goto out_free_glue;
 352         }
 353
 354         glue->core = platform_device_alloc("wl12xx", -1);
 355         if (!glue->core) {
 356                 dev_err(glue->dev, "can't allocate platform_device\n");
 357                 ret = -ENOMEM;
 358                 goto out_free_glue;
 359         }
 360
 361         glue->core->dev.parent = &spi->dev;
 362
 363         memset(res, 0x00, sizeof(res));
 364
 365         res[0].start = spi->irq;
 366         res[0].flags = IORESOURCE_IRQ;
 367         res[0].name = "irq";
 368
 369         ret = platform_device_add_resources(glue->core, res, ARRAY_SIZE(res));
 370         if (ret) {
 371                 dev_err(glue->dev, "can't add resources\n");
 372                 goto out_dev_put;
 373         }
 374
 375         ret = platform_device_add_data(glue->core, pdata, sizeof(*pdata));
 376         if (ret) {
 377                 dev_err(glue->dev, "can't add platform data\n");
 378                 goto out_dev_put;
 379         }
 380
 381         ret = platform_device_add(glue->core);
 382         if (ret) {
 383                 dev_err(glue->dev, "can't register platform device\n");
 384                 goto out_dev_put;
 385         }
 386
 387         return 0;
 388
 389 out_dev_put:
 390         platform_device_put(glue->core);
 391
 392 out_free_glue:
 393         kfree(glue);
 394 out:
 395         return ret;
 396 }
 397
 398 static int wl1271_remove(struct spi_device *spi)
 399 {
 400         struct wl12xx_spi_glue *glue = spi_get_drvdata(spi);
 401
 402         platform_device_del(glue->core);
 403         platform_device_put(glue->core);
 404         kfree(glue);
 405
 406         return 0;
 407 }
 408
 409
 410 static struct spi_driver wl1271_spi_driver = {
 411         .driver = {
 412                 .name           = "wl1271_spi",
 413                 .owner          = THIS_MODULE,
 414         },
 415
 416         .probe          = wl1271_probe,
 417         .remove         = wl1271_remove,
 418 };
 419
 420 static int __init wl1271_init(void)
 421 {
 422         return spi_register_driver(&wl1271_spi_driver);
 423 }
 424
 425 static void __exit wl1271_exit(void)
 426 {
 427         spi_unregister_driver(&wl1271_spi_driver);
 428 }
 429
 430 module_init(wl1271_init);
 431 module_exit(wl1271_exit);
 432
 433 MODULE_LICENSE("GPL");
 434 MODULE_AUTHOR("Luciano Coelho <coelho@ti.com>");
 435 MODULE_AUTHOR("Juuso Oikarinen <juuso.oikarinen@nokia.com>");
 436 MODULE_ALIAS("spi:wl1271");