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 /* Maximum number of SPI write chunks */
  76 #define WSPI_MAX_NUM_OF_CHUNKS \
  77         ((SPI_AGGR_BUFFER_SIZE / WSPI_MAX_CHUNK_SIZE) + 1)
  78
  79
  80 struct wl12xx_spi_glue {
  81         struct device *dev;
  82         struct platform_device *core;
  83 };
  84
  85 static void wl12xx_spi_reset(struct device *child)
  86 {
  87         struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
  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                 dev_err(child->parent,
  95                         "could not allocate cmd for spi reset\n");
  96                 return;
  97         }
  98
  99         memset(&t, 0, sizeof(t));
 100         spi_message_init(&m);
 101
 102         memset(cmd, 0xff, WSPI_INIT_CMD_LEN);
 103
 104         t.tx_buf = cmd;
 105         t.len = WSPI_INIT_CMD_LEN;
 106         spi_message_add_tail(&t, &m);
 107
 108         spi_sync(to_spi_device(glue->dev), &m);
 109
 110         kfree(cmd);
 111 }
 112
 113 static void wl12xx_spi_init(struct device *child)
 114 {
 115         struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
 116         u8 crc[WSPI_INIT_CMD_CRC_LEN], *cmd;
 117         struct spi_transfer t;
 118         struct spi_message m;
 119
 120         cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
 121         if (!cmd) {
 122                 dev_err(child->parent,
 123                         "could not allocate cmd for spi init\n");
 124                 return;
 125         }
 126
 127         memset(crc, 0, sizeof(crc));
 128         memset(&t, 0, sizeof(t));
 129         spi_message_init(&m);
 130
 131         /*
 132          * Set WSPI_INIT_COMMAND
 133          * the data is being send from the MSB to LSB
 134          */
 135         cmd[2] = 0xff;
 136         cmd[3] = 0xff;
 137         cmd[1] = WSPI_INIT_CMD_START | WSPI_INIT_CMD_TX;
 138         cmd[0] = 0;
 139         cmd[7] = 0;
 140         cmd[6] |= HW_ACCESS_WSPI_INIT_CMD_MASK << 3;
 141         cmd[6] |= HW_ACCESS_WSPI_FIXED_BUSY_LEN & WSPI_INIT_CMD_FIXEDBUSY_LEN;
 142
 143         if (HW_ACCESS_WSPI_FIXED_BUSY_LEN == 0)
 144                 cmd[5] |=  WSPI_INIT_CMD_DIS_FIXEDBUSY;
 145         else
 146                 cmd[5] |= WSPI_INIT_CMD_EN_FIXEDBUSY;
 147
 148         cmd[5] |= WSPI_INIT_CMD_IOD | WSPI_INIT_CMD_IP | WSPI_INIT_CMD_CS
 149                 | WSPI_INIT_CMD_WSPI | WSPI_INIT_CMD_WS;
 150
 151         crc[0] = cmd[1];
 152         crc[1] = cmd[0];
 153         crc[2] = cmd[7];
 154         crc[3] = cmd[6];
 155         crc[4] = cmd[5];
 156
 157         cmd[4] |= crc7(0, crc, WSPI_INIT_CMD_CRC_LEN) << 1;
 158         cmd[4] |= WSPI_INIT_CMD_END;
 159
 160         t.tx_buf = cmd;
 161         t.len = WSPI_INIT_CMD_LEN;
 162         spi_message_add_tail(&t, &m);
 163
 164         spi_sync(to_spi_device(glue->dev), &m);
 165         kfree(cmd);
 166 }
 167
 168 #define WL1271_BUSY_WORD_TIMEOUT 1000
 169
 170 static int wl12xx_spi_read_busy(struct device *child)
 171 {
 172         struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
 173         struct wl1271 *wl = dev_get_drvdata(child);
 174         struct spi_transfer t[1];
 175         struct spi_message m;
 176         u32 *busy_buf;
 177         int num_busy_bytes = 0;
 178
 179         /*
 180          * Read further busy words from SPI until a non-busy word is
 181          * encountered, then read the data itself into the buffer.
 182          */
 183
 184         num_busy_bytes = WL1271_BUSY_WORD_TIMEOUT;
 185         busy_buf = wl->buffer_busyword;
 186         while (num_busy_bytes) {
 187                 num_busy_bytes--;
 188                 spi_message_init(&m);
 189                 memset(t, 0, sizeof(t));
 190                 t[0].rx_buf = busy_buf;
 191                 t[0].len = sizeof(u32);
 192                 t[0].cs_change = true;
 193                 spi_message_add_tail(&t[0], &m);
 194                 spi_sync(to_spi_device(glue->dev), &m);
 195
 196                 if (*busy_buf & 0x1)
 197                         return 0;
 198         }
 199
 200         /* The SPI bus is unresponsive, the read failed. */
 201         dev_err(child->parent, "SPI read busy-word timeout!\n");
 202         return -ETIMEDOUT;
 203 }
 204
 205 static int __must_check wl12xx_spi_raw_read(struct device *child, int addr,
 206                                             void *buf, size_t len, bool fixed)
 207 {
 208         struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
 209         struct wl1271 *wl = dev_get_drvdata(child);
 210         struct spi_transfer t[2];
 211         struct spi_message m;
 212         u32 *busy_buf;
 213         u32 *cmd;
 214         u32 chunk_len;
 215
 216         while (len > 0) {
 217                 chunk_len = min((size_t)WSPI_MAX_CHUNK_SIZE, len);
 218
 219                 cmd = &wl->buffer_cmd;
 220                 busy_buf = wl->buffer_busyword;
 221
 222                 *cmd = 0;
 223                 *cmd |= WSPI_CMD_READ;
 224                 *cmd |= (chunk_len << WSPI_CMD_BYTE_LENGTH_OFFSET) &
 225                         WSPI_CMD_BYTE_LENGTH;
 226                 *cmd |= addr & WSPI_CMD_BYTE_ADDR;
 227
 228                 if (fixed)
 229                         *cmd |= WSPI_CMD_FIXED;
 230
 231                 spi_message_init(&m);
 232                 memset(t, 0, sizeof(t));
 233
 234                 t[0].tx_buf = cmd;
 235                 t[0].len = 4;
 236                 t[0].cs_change = true;
 237                 spi_message_add_tail(&t[0], &m);
 238
 239                 /* Busy and non busy words read */
 240                 t[1].rx_buf = busy_buf;
 241                 t[1].len = WL1271_BUSY_WORD_LEN;
 242                 t[1].cs_change = true;
 243                 spi_message_add_tail(&t[1], &m);
 244
 245                 spi_sync(to_spi_device(glue->dev), &m);
 246
 247                 if (!(busy_buf[WL1271_BUSY_WORD_CNT - 1] & 0x1) &&
 248                     wl12xx_spi_read_busy(child)) {
 249                         memset(buf, 0, chunk_len);
 250                         return 0;
 251                 }
 252
 253                 spi_message_init(&m);
 254                 memset(t, 0, sizeof(t));
 255
 256                 t[0].rx_buf = buf;
 257                 t[0].len = chunk_len;
 258                 t[0].cs_change = true;
 259                 spi_message_add_tail(&t[0], &m);
 260
 261                 spi_sync(to_spi_device(glue->dev), &m);
 262
 263                 if (!fixed)
 264                         addr += chunk_len;
 265                 buf += chunk_len;
 266                 len -= chunk_len;
 267         }
 268
 269         return 0;
 270 }
 271
 272 static int __must_check wl12xx_spi_raw_write(struct device *child, int addr,
 273                                              void *buf, size_t len, bool fixed)
 274 {
 275         struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
 276         /* SPI write buffers - 2 for each chunk */
 277         struct spi_transfer t[2 * WSPI_MAX_NUM_OF_CHUNKS];
 278         struct spi_message m;
 279         u32 commands[WSPI_MAX_NUM_OF_CHUNKS]; /* 1 command per chunk */
 280         u32 *cmd;
 281         u32 chunk_len;
 282         int i;
 283
 284         WARN_ON(len > SPI_AGGR_BUFFER_SIZE);
 285
 286         spi_message_init(&m);
 287         memset(t, 0, sizeof(t));
 288
 289         cmd = &commands[0];
 290         i = 0;
 291         while (len > 0) {
 292                 chunk_len = min((size_t)WSPI_MAX_CHUNK_SIZE, len);
 293
 294                 *cmd = 0;
 295                 *cmd |= WSPI_CMD_WRITE;
 296                 *cmd |= (chunk_len << WSPI_CMD_BYTE_LENGTH_OFFSET) &
 297                         WSPI_CMD_BYTE_LENGTH;
 298                 *cmd |= addr & WSPI_CMD_BYTE_ADDR;
 299
 300                 if (fixed)
 301                         *cmd |= WSPI_CMD_FIXED;
 302
 303                 t[i].tx_buf = cmd;
 304                 t[i].len = sizeof(*cmd);
 305                 spi_message_add_tail(&t[i++], &m);
 306
 307                 t[i].tx_buf = buf;
 308                 t[i].len = chunk_len;
 309                 spi_message_add_tail(&t[i++], &m);
 310
 311                 if (!fixed)
 312                         addr += chunk_len;
 313                 buf += chunk_len;
 314                 len -= chunk_len;
 315                 cmd++;
 316         }
 317
 318         spi_sync(to_spi_device(glue->dev), &m);
 319
 320         return 0;
 321 }
 322
 323 static struct wl1271_if_operations spi_ops = {
 324         .read           = wl12xx_spi_raw_read,
 325         .write          = wl12xx_spi_raw_write,
 326         .reset          = wl12xx_spi_reset,
 327         .init           = wl12xx_spi_init,
 328         .set_block_size = NULL,
 329 };
 330
 331 static int wl1271_probe(struct spi_device *spi)
 332 {
 333         struct wl12xx_spi_glue *glue;
 334         struct wlcore_platdev_data *pdev_data;
 335         struct resource res[1];
 336         int ret = -ENOMEM;
 337
 338         pdev_data = kzalloc(sizeof(*pdev_data), GFP_KERNEL);
 339         if (!pdev_data)
 340                 goto out;
 341
 342         pdev_data->pdata = spi->dev.platform_data;
 343         if (!pdev_data->pdata) {
 344                 dev_err(&spi->dev, "no platform data\n");
 345                 ret = -ENODEV;
 346                 goto out_free_pdev_data;
 347         }
 348
 349         pdev_data->if_ops = &spi_ops;
 350
 351         glue = kzalloc(sizeof(*glue), GFP_KERNEL);
 352         if (!glue) {
 353                 dev_err(&spi->dev, "can't allocate glue\n");
 354                 goto out_free_pdev_data;
 355         }
 356
 357         glue->dev = &spi->dev;
 358
 359         spi_set_drvdata(spi, glue);
 360
 361         /* This is the only SPI value that we need to set here, the rest
 362          * comes from the board-peripherals file */
 363         spi->bits_per_word = 32;
 364
 365         ret = spi_setup(spi);
 366         if (ret < 0) {
 367                 dev_err(glue->dev, "spi_setup failed\n");
 368                 goto out_free_glue;
 369         }
 370
 371         glue->core = platform_device_alloc("wl12xx", PLATFORM_DEVID_AUTO);
 372         if (!glue->core) {
 373                 dev_err(glue->dev, "can't allocate platform_device\n");
 374                 ret = -ENOMEM;
 375                 goto out_free_glue;
 376         }
 377
 378         glue->core->dev.parent = &spi->dev;
 379
 380         memset(res, 0x00, sizeof(res));
 381
 382         res[0].start = spi->irq;
 383         res[0].flags = IORESOURCE_IRQ;
 384         res[0].name = "irq";
 385
 386         ret = platform_device_add_resources(glue->core, res, ARRAY_SIZE(res));
 387         if (ret) {
 388                 dev_err(glue->dev, "can't add resources\n");
 389                 goto out_dev_put;
 390         }
 391
 392         ret = platform_device_add_data(glue->core, pdev_data,
 393                                        sizeof(*pdev_data));
 394         if (ret) {
 395                 dev_err(glue->dev, "can't add platform data\n");
 396                 goto out_dev_put;
 397         }
 398
 399         ret = platform_device_add(glue->core);
 400         if (ret) {
 401                 dev_err(glue->dev, "can't register platform device\n");
 402                 goto out_dev_put;
 403         }
 404
 405         return 0;
 406
 407 out_dev_put:
 408         platform_device_put(glue->core);
 409
 410 out_free_glue:
 411         kfree(glue);
 412
 413 out_free_pdev_data:
 414         kfree(pdev_data);
 415
 416 out:
 417         return ret;
 418 }
 419
 420 static int wl1271_remove(struct spi_device *spi)
 421 {
 422         struct wl12xx_spi_glue *glue = spi_get_drvdata(spi);
 423
 424         platform_device_unregister(glue->core);
 425         kfree(glue);
 426
 427         return 0;
 428 }
 429
 430
 431 static struct spi_driver wl1271_spi_driver = {
 432         .driver = {
 433                 .name           = "wl1271_spi",
 434                 .owner          = THIS_MODULE,
 435         },
 436
 437         .probe          = wl1271_probe,
 438         .remove         = wl1271_remove,
 439 };
 440
 441 module_spi_driver(wl1271_spi_driver);
 442 MODULE_LICENSE("GPL");
 443 MODULE_AUTHOR("Luciano Coelho <coelho@ti.com>");
 444 MODULE_AUTHOR("Juuso Oikarinen <juuso.oikarinen@nokia.com>");
 445 MODULE_ALIAS("spi:wl1271");