kernel/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/slab.h>
  28 #include <linux/swab.h>
  29 #include <linux/crc7.h>
  30 #include <linux/spi/spi.h>
  31 #include <linux/wl12xx.h>
  32 #include <linux/platform_device.h>
  33
  34 #include "wlcore.h"
  35 #include "wl12xx_80211.h"
  36 #include "io.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 /*
  71  * only support SPI for 12xx - this code should be reworked when 18xx
  72  * support is introduced
  73  */
  74 #define SPI_AGGR_BUFFER_SIZE (4 * PAGE_SIZE)
  75
  76 #define WSPI_MAX_NUM_OF_CHUNKS (SPI_AGGR_BUFFER_SIZE / WSPI_MAX_CHUNK_SIZE)
  77
  78 struct wl12xx_spi_glue {
  79         struct device *dev;
  80         struct platform_device *core;
  81 };
  82
  83 static void wl12xx_spi_reset(struct device *child)
  84 {
  85         struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
  86         u8 *cmd;
  87         struct spi_transfer t;
  88         struct spi_message m;
  89
  90         cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
  91         if (!cmd) {
  92                 dev_err(child->parent,
  93                         "could not allocate cmd for spi reset\n");
  94                 return;
  95         }
  96
  97         memset(&t, 0, sizeof(t));
  98         spi_message_init(&m);
  99
 100         memset(cmd, 0xff, WSPI_INIT_CMD_LEN);
 101
 102         t.tx_buf = cmd;
 103         t.len = WSPI_INIT_CMD_LEN;
 104         spi_message_add_tail(&t, &m);
 105
 106         spi_sync(to_spi_device(glue->dev), &m);
 107
 108         kfree(cmd);
 109 }
 110
 111 static void wl12xx_spi_init(struct device *child)
 112 {
 113         struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
 114         struct spi_transfer t;
 115         struct spi_message m;
 116         u8 *cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
 117
 118         if (!cmd) {
 119                 dev_err(child->parent,
 120                         "could not allocate cmd for spi init\n");
 121                 return;
 122         }
 123
 124         memset(&t, 0, sizeof(t));
 125         spi_message_init(&m);
 126
 127         /*
 128          * Set WSPI_INIT_COMMAND
 129          * the data is being send from the MSB to LSB
 130          */
 131         cmd[0] = 0xff;
 132         cmd[1] = 0xff;
 133         cmd[2] = WSPI_INIT_CMD_START | WSPI_INIT_CMD_TX;
 134         cmd[3] = 0;
 135         cmd[4] = 0;
 136         cmd[5] = HW_ACCESS_WSPI_INIT_CMD_MASK << 3;
 137         cmd[5] |= HW_ACCESS_WSPI_FIXED_BUSY_LEN & WSPI_INIT_CMD_FIXEDBUSY_LEN;
 138
 139         cmd[6] = WSPI_INIT_CMD_IOD | WSPI_INIT_CMD_IP | WSPI_INIT_CMD_CS
 140                 | WSPI_INIT_CMD_WSPI | WSPI_INIT_CMD_WS;
 141
 142         if (HW_ACCESS_WSPI_FIXED_BUSY_LEN == 0)
 143                 cmd[6] |= WSPI_INIT_CMD_DIS_FIXEDBUSY;
 144         else
 145                 cmd[6] |= WSPI_INIT_CMD_EN_FIXEDBUSY;
 146
 147         cmd[7] = crc7_be(0, cmd+2, WSPI_INIT_CMD_CRC_LEN) | WSPI_INIT_CMD_END;
 148         /*
 149          * The above is the logical order; it must actually be stored
 150          * in the buffer byte-swapped.
 151          */
 152         __swab32s((u32 *)cmd);
 153         __swab32s((u32 *)cmd+1);
 154
 155         t.tx_buf = cmd;
 156         t.len = WSPI_INIT_CMD_LEN;
 157         spi_message_add_tail(&t, &m);
 158
 159         spi_sync(to_spi_device(glue->dev), &m);
 160         kfree(cmd);
 161 }
 162
 163 #define WL1271_BUSY_WORD_TIMEOUT 1000
 164
 165 static int wl12xx_spi_read_busy(struct device *child)
 166 {
 167         struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
 168         struct wl1271 *wl = dev_get_drvdata(child);
 169         struct spi_transfer t[1];
 170         struct spi_message m;
 171         u32 *busy_buf;
 172         int num_busy_bytes = 0;
 173
 174         /*
 175          * Read further busy words from SPI until a non-busy word is
 176          * encountered, then read the data itself into the buffer.
 177          */
 178
 179         num_busy_bytes = WL1271_BUSY_WORD_TIMEOUT;
 180         busy_buf = wl->buffer_busyword;
 181         while (num_busy_bytes) {
 182                 num_busy_bytes--;
 183                 spi_message_init(&m);
 184                 memset(t, 0, sizeof(t));
 185                 t[0].rx_buf = busy_buf;
 186                 t[0].len = sizeof(u32);
 187                 t[0].cs_change = true;
 188                 spi_message_add_tail(&t[0], &m);
 189                 spi_sync(to_spi_device(glue->dev), &m);
 190
 191                 if (*busy_buf & 0x1)
 192                         return 0;
 193         }
 194
 195         /* The SPI bus is unresponsive, the read failed. */
 196         dev_err(child->parent, "SPI read busy-word timeout!\n");
 197         return -ETIMEDOUT;
 198 }
 199
 200 static int __must_check wl12xx_spi_raw_read(struct device *child, int addr,
 201                                             void *buf, size_t len, bool fixed)
 202 {
 203         struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
 204         struct wl1271 *wl = dev_get_drvdata(child);
 205         struct spi_transfer t[2];
 206         struct spi_message m;
 207         u32 *busy_buf;
 208         u32 *cmd;
 209         u32 chunk_len;
 210
 211         while (len > 0) {
 212                 chunk_len = min_t(size_t, WSPI_MAX_CHUNK_SIZE, len);
 213
 214                 cmd = &wl->buffer_cmd;
 215                 busy_buf = wl->buffer_busyword;
 216
 217                 *cmd = 0;
 218                 *cmd |= WSPI_CMD_READ;
 219                 *cmd |= (chunk_len << WSPI_CMD_BYTE_LENGTH_OFFSET) &
 220                         WSPI_CMD_BYTE_LENGTH;
 221                 *cmd |= addr & WSPI_CMD_BYTE_ADDR;
 222
 223                 if (fixed)
 224                         *cmd |= WSPI_CMD_FIXED;
 225
 226                 spi_message_init(&m);
 227                 memset(t, 0, sizeof(t));
 228
 229                 t[0].tx_buf = cmd;
 230                 t[0].len = 4;
 231                 t[0].cs_change = true;
 232                 spi_message_add_tail(&t[0], &m);
 233
 234                 /* Busy and non busy words read */
 235                 t[1].rx_buf = busy_buf;
 236                 t[1].len = WL1271_BUSY_WORD_LEN;
 237                 t[1].cs_change = true;
 238                 spi_message_add_tail(&t[1], &m);
 239
 240                 spi_sync(to_spi_device(glue->dev), &m);
 241
 242                 if (!(busy_buf[WL1271_BUSY_WORD_CNT - 1] & 0x1) &&
 243                     wl12xx_spi_read_busy(child)) {
 244                         memset(buf, 0, chunk_len);
 245                         return 0;
 246                 }
 247
 248                 spi_message_init(&m);
 249                 memset(t, 0, sizeof(t));
 250
 251                 t[0].rx_buf = buf;
 252                 t[0].len = chunk_len;
 253                 t[0].cs_change = true;
 254                 spi_message_add_tail(&t[0], &m);
 255
 256                 spi_sync(to_spi_device(glue->dev), &m);
 257
 258                 if (!fixed)
 259                         addr += chunk_len;
 260                 buf += chunk_len;
 261                 len -= chunk_len;
 262         }
 263
 264         return 0;
 265 }
 266
 267 static int __must_check wl12xx_spi_raw_write(struct device *child, int addr,
 268                                              void *buf, size_t len, bool fixed)
 269 {
 270         struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
 271         struct spi_transfer t[2 * (WSPI_MAX_NUM_OF_CHUNKS + 1)];
 272         struct spi_message m;
 273         u32 commands[WSPI_MAX_NUM_OF_CHUNKS];
 274         u32 *cmd;
 275         u32 chunk_len;
 276         int i;
 277
 278         WARN_ON(len > SPI_AGGR_BUFFER_SIZE);
 279
 280         spi_message_init(&m);
 281         memset(t, 0, sizeof(t));
 282
 283         cmd = &commands[0];
 284         i = 0;
 285         while (len > 0) {
 286                 chunk_len = min_t(size_t, WSPI_MAX_CHUNK_SIZE, len);
 287
 288                 *cmd = 0;
 289                 *cmd |= WSPI_CMD_WRITE;
 290                 *cmd |= (chunk_len << WSPI_CMD_BYTE_LENGTH_OFFSET) &
 291                         WSPI_CMD_BYTE_LENGTH;
 292                 *cmd |= addr & WSPI_CMD_BYTE_ADDR;
 293
 294                 if (fixed)
 295                         *cmd |= WSPI_CMD_FIXED;
 296
 297                 t[i].tx_buf = cmd;
 298                 t[i].len = sizeof(*cmd);
 299                 spi_message_add_tail(&t[i++], &m);
 300
 301                 t[i].tx_buf = buf;
 302                 t[i].len = chunk_len;
 303                 spi_message_add_tail(&t[i++], &m);
 304
 305                 if (!fixed)
 306                         addr += chunk_len;
 307                 buf += chunk_len;
 308                 len -= chunk_len;
 309                 cmd++;
 310         }
 311
 312         spi_sync(to_spi_device(glue->dev), &m);
 313
 314         return 0;
 315 }
 316
 317 static struct wl1271_if_operations spi_ops = {
 318         .read           = wl12xx_spi_raw_read,
 319         .write          = wl12xx_spi_raw_write,
 320         .reset          = wl12xx_spi_reset,
 321         .init           = wl12xx_spi_init,
 322         .set_block_size = NULL,
 323 };
 324
 325 static int wl1271_probe(struct spi_device *spi)
 326 {
 327         struct wl12xx_spi_glue *glue;
 328         struct wlcore_platdev_data pdev_data;
 329         struct resource res[1];
 330         int ret;
 331
 332         memset(&pdev_data, 0x00, sizeof(pdev_data));
 333
 334         /* TODO: add DT parsing when needed */
 335
 336         pdev_data.if_ops = &spi_ops;
 337
 338         glue = devm_kzalloc(&spi->dev, sizeof(*glue), GFP_KERNEL);
 339         if (!glue) {
 340                 dev_err(&spi->dev, "can't allocate glue\n");
 341                 return -ENOMEM;
 342         }
 343
 344         glue->dev = &spi->dev;
 345
 346         spi_set_drvdata(spi, glue);
 347
 348         /* This is the only SPI value that we need to set here, the rest
 349          * comes from the board-peripherals file */
 350         spi->bits_per_word = 32;
 351
 352         ret = spi_setup(spi);
 353         if (ret < 0) {
 354                 dev_err(glue->dev, "spi_setup failed\n");
 355                 return ret;
 356         }
 357
 358         glue->core = platform_device_alloc("wl12xx", PLATFORM_DEVID_AUTO);
 359         if (!glue->core) {
 360                 dev_err(glue->dev, "can't allocate platform_device\n");
 361                 return -ENOMEM;
 362         }
 363
 364         glue->core->dev.parent = &spi->dev;
 365
 366         memset(res, 0x00, sizeof(res));
 367
 368         res[0].start = spi->irq;
 369         res[0].flags = IORESOURCE_IRQ;
 370         res[0].name = "irq";
 371
 372         ret = platform_device_add_resources(glue->core, res, ARRAY_SIZE(res));
 373         if (ret) {
 374                 dev_err(glue->dev, "can't add resources\n");
 375                 goto out_dev_put;
 376         }
 377
 378         ret = platform_device_add_data(glue->core, &pdev_data,
 379                                        sizeof(pdev_data));
 380         if (ret) {
 381                 dev_err(glue->dev, "can't add platform data\n");
 382                 goto out_dev_put;
 383         }
 384
 385         ret = platform_device_add(glue->core);
 386         if (ret) {
 387                 dev_err(glue->dev, "can't register platform device\n");
 388                 goto out_dev_put;
 389         }
 390
 391         return 0;
 392
 393 out_dev_put:
 394         platform_device_put(glue->core);
 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_unregister(glue->core);
 403
 404         return 0;
 405 }
 406
 407
 408 static struct spi_driver wl1271_spi_driver = {
 409         .driver = {
 410                 .name           = "wl1271_spi",
 411                 .owner          = THIS_MODULE,
 412         },
 413
 414         .probe          = wl1271_probe,
 415         .remove         = wl1271_remove,
 416 };
 417
 418 module_spi_driver(wl1271_spi_driver);
 419 MODULE_LICENSE("GPL");
 420 MODULE_AUTHOR("Luciano Coelho <coelho@ti.com>");
 421 MODULE_AUTHOR("Juuso Oikarinen <juuso.oikarinen@nokia.com>");
 422 MODULE_ALIAS("spi:wl1271");