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 #include <linux/of_irq.h>
  34 #include <linux/regulator/consumer.h>
  35
  36 #include "wlcore.h"
  37 #include "wl12xx_80211.h"
  38 #include "io.h"
  39
  40 #define WSPI_CMD_READ                 0x40000000
  41 #define WSPI_CMD_WRITE                0x00000000
  42 #define WSPI_CMD_FIXED                0x20000000
  43 #define WSPI_CMD_BYTE_LENGTH          0x1FFE0000
  44 #define WSPI_CMD_BYTE_LENGTH_OFFSET   17
  45 #define WSPI_CMD_BYTE_ADDR            0x0001FFFF
  46
  47 #define WSPI_INIT_CMD_CRC_LEN       5
  48
  49 #define WSPI_INIT_CMD_START         0x00
  50 #define WSPI_INIT_CMD_TX            0x40
  51 /* the extra bypass bit is sampled by the TNET as '1' */
  52 #define WSPI_INIT_CMD_BYPASS_BIT    0x80
  53 #define WSPI_INIT_CMD_FIXEDBUSY_LEN 0x07
  54 #define WSPI_INIT_CMD_EN_FIXEDBUSY  0x80
  55 #define WSPI_INIT_CMD_DIS_FIXEDBUSY 0x00
  56 #define WSPI_INIT_CMD_IOD           0x40
  57 #define WSPI_INIT_CMD_IP            0x20
  58 #define WSPI_INIT_CMD_CS            0x10
  59 #define WSPI_INIT_CMD_WS            0x08
  60 #define WSPI_INIT_CMD_WSPI          0x01
  61 #define WSPI_INIT_CMD_END           0x01
  62
  63 #define WSPI_INIT_CMD_LEN           8
  64
  65 #define HW_ACCESS_WSPI_FIXED_BUSY_LEN \
  66                 ((WL1271_BUSY_WORD_LEN - 4) / sizeof(u32))
  67 #define HW_ACCESS_WSPI_INIT_CMD_MASK  0
  68
  69 /* HW limitation: maximum possible chunk size is 4095 bytes */
  70 #define WSPI_MAX_CHUNK_SIZE    4092
  71
  72 /*
  73  * only support SPI for 12xx - this code should be reworked when 18xx
  74  * support is introduced
  75  */
  76 #define SPI_AGGR_BUFFER_SIZE (4 * PAGE_SIZE)
  77
  78 /* Maximum number of SPI write chunks */
  79 #define WSPI_MAX_NUM_OF_CHUNKS \
  80         ((SPI_AGGR_BUFFER_SIZE / WSPI_MAX_CHUNK_SIZE) + 1)
  81
  82
  83 struct wl12xx_spi_glue {
  84         struct device *dev;
  85         struct platform_device *core;
  86         struct regulator *reg; /* Power regulator */
  87 };
  88
  89 static void wl12xx_spi_reset(struct device *child)
  90 {
  91         struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
  92         u8 *cmd;
  93         struct spi_transfer t;
  94         struct spi_message m;
  95
  96         cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
  97         if (!cmd) {
  98                 dev_err(child->parent,
  99                         "could not allocate cmd for spi reset\n");
 100                 return;
 101         }
 102
 103         memset(&t, 0, sizeof(t));
 104         spi_message_init(&m);
 105
 106         memset(cmd, 0xff, WSPI_INIT_CMD_LEN);
 107
 108         t.tx_buf = cmd;
 109         t.len = WSPI_INIT_CMD_LEN;
 110         spi_message_add_tail(&t, &m);
 111
 112         spi_sync(to_spi_device(glue->dev), &m);
 113
 114         kfree(cmd);
 115 }
 116
 117 static void wl12xx_spi_init(struct device *child)
 118 {
 119         struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
 120         struct spi_transfer t;
 121         struct spi_message m;
 122         u8 *cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
 123
 124         if (!cmd) {
 125                 dev_err(child->parent,
 126                         "could not allocate cmd for spi init\n");
 127                 return;
 128         }
 129
 130         memset(&t, 0, sizeof(t));
 131         spi_message_init(&m);
 132
 133         /*
 134          * Set WSPI_INIT_COMMAND
 135          * the data is being send from the MSB to LSB
 136          */
 137         cmd[0] = 0xff;
 138         cmd[1] = 0xff;
 139         cmd[2] = WSPI_INIT_CMD_START | WSPI_INIT_CMD_TX;
 140         cmd[3] = 0;
 141         cmd[4] = 0;
 142         cmd[5] = HW_ACCESS_WSPI_INIT_CMD_MASK << 3;
 143         cmd[5] |= HW_ACCESS_WSPI_FIXED_BUSY_LEN & WSPI_INIT_CMD_FIXEDBUSY_LEN;
 144
 145         cmd[6] = WSPI_INIT_CMD_IOD | WSPI_INIT_CMD_IP | WSPI_INIT_CMD_CS
 146                 | WSPI_INIT_CMD_WSPI | WSPI_INIT_CMD_WS;
 147
 148         if (HW_ACCESS_WSPI_FIXED_BUSY_LEN == 0)
 149                 cmd[6] |= WSPI_INIT_CMD_DIS_FIXEDBUSY;
 150         else
 151                 cmd[6] |= WSPI_INIT_CMD_EN_FIXEDBUSY;
 152
 153         cmd[7] = crc7_be(0, cmd+2, WSPI_INIT_CMD_CRC_LEN) | WSPI_INIT_CMD_END;
 154         /*
 155          * The above is the logical order; it must actually be stored
 156          * in the buffer byte-swapped.
 157          */
 158         __swab32s((u32 *)cmd);
 159         __swab32s((u32 *)cmd+1);
 160
 161         t.tx_buf = cmd;
 162         t.len = WSPI_INIT_CMD_LEN;
 163         spi_message_add_tail(&t, &m);
 164
 165         spi_sync(to_spi_device(glue->dev), &m);
 166         kfree(cmd);
 167 }
 168
 169 #define WL1271_BUSY_WORD_TIMEOUT 1000
 170
 171 static int wl12xx_spi_read_busy(struct device *child)
 172 {
 173         struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
 174         struct wl1271 *wl = dev_get_drvdata(child);
 175         struct spi_transfer t[1];
 176         struct spi_message m;
 177         u32 *busy_buf;
 178         int num_busy_bytes = 0;
 179
 180         /*
 181          * Read further busy words from SPI until a non-busy word is
 182          * encountered, then read the data itself into the buffer.
 183          */
 184
 185         num_busy_bytes = WL1271_BUSY_WORD_TIMEOUT;
 186         busy_buf = wl->buffer_busyword;
 187         while (num_busy_bytes) {
 188                 num_busy_bytes--;
 189                 spi_message_init(&m);
 190                 memset(t, 0, sizeof(t));
 191                 t[0].rx_buf = busy_buf;
 192                 t[0].len = sizeof(u32);
 193                 t[0].cs_change = true;
 194                 spi_message_add_tail(&t[0], &m);
 195                 spi_sync(to_spi_device(glue->dev), &m);
 196
 197                 if (*busy_buf & 0x1)
 198                         return 0;
 199         }
 200
 201         /* The SPI bus is unresponsive, the read failed. */
 202         dev_err(child->parent, "SPI read busy-word timeout!\n");
 203         return -ETIMEDOUT;
 204 }
 205
 206 static int __must_check wl12xx_spi_raw_read(struct device *child, int addr,
 207                                             void *buf, size_t len, bool fixed)
 208 {
 209         struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
 210         struct wl1271 *wl = dev_get_drvdata(child);
 211         struct spi_transfer t[2];
 212         struct spi_message m;
 213         u32 *busy_buf;
 214         u32 *cmd;
 215         u32 chunk_len;
 216
 217         while (len > 0) {
 218                 chunk_len = min_t(size_t, WSPI_MAX_CHUNK_SIZE, len);
 219
 220                 cmd = &wl->buffer_cmd;
 221                 busy_buf = wl->buffer_busyword;
 222
 223                 *cmd = 0;
 224                 *cmd |= WSPI_CMD_READ;
 225                 *cmd |= (chunk_len << WSPI_CMD_BYTE_LENGTH_OFFSET) &
 226                         WSPI_CMD_BYTE_LENGTH;
 227                 *cmd |= addr & WSPI_CMD_BYTE_ADDR;
 228
 229                 if (fixed)
 230                         *cmd |= WSPI_CMD_FIXED;
 231
 232                 spi_message_init(&m);
 233                 memset(t, 0, sizeof(t));
 234
 235                 t[0].tx_buf = cmd;
 236                 t[0].len = 4;
 237                 t[0].cs_change = true;
 238                 spi_message_add_tail(&t[0], &m);
 239
 240                 /* Busy and non busy words read */
 241                 t[1].rx_buf = busy_buf;
 242                 t[1].len = WL1271_BUSY_WORD_LEN;
 243                 t[1].cs_change = true;
 244                 spi_message_add_tail(&t[1], &m);
 245
 246                 spi_sync(to_spi_device(glue->dev), &m);
 247
 248                 if (!(busy_buf[WL1271_BUSY_WORD_CNT - 1] & 0x1) &&
 249                     wl12xx_spi_read_busy(child)) {
 250                         memset(buf, 0, chunk_len);
 251                         return 0;
 252                 }
 253
 254                 spi_message_init(&m);
 255                 memset(t, 0, sizeof(t));
 256
 257                 t[0].rx_buf = buf;
 258                 t[0].len = chunk_len;
 259                 t[0].cs_change = true;
 260                 spi_message_add_tail(&t[0], &m);
 261
 262                 spi_sync(to_spi_device(glue->dev), &m);
 263
 264                 if (!fixed)
 265                         addr += chunk_len;
 266                 buf += chunk_len;
 267                 len -= chunk_len;
 268         }
 269
 270         return 0;
 271 }
 272
 273 static int __must_check wl12xx_spi_raw_write(struct device *child, int addr,
 274                                              void *buf, size_t len, bool fixed)
 275 {
 276         struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
 277         /* SPI write buffers - 2 for each chunk */
 278         struct spi_transfer t[2 * WSPI_MAX_NUM_OF_CHUNKS];
 279         struct spi_message m;
 280         u32 commands[WSPI_MAX_NUM_OF_CHUNKS]; /* 1 command per chunk */
 281         u32 *cmd;
 282         u32 chunk_len;
 283         int i;
 284
 285         WARN_ON(len > SPI_AGGR_BUFFER_SIZE);
 286
 287         spi_message_init(&m);
 288         memset(t, 0, sizeof(t));
 289
 290         cmd = &commands[0];
 291         i = 0;
 292         while (len > 0) {
 293                 chunk_len = min_t(size_t, WSPI_MAX_CHUNK_SIZE, len);
 294
 295                 *cmd = 0;
 296                 *cmd |= WSPI_CMD_WRITE;
 297                 *cmd |= (chunk_len << WSPI_CMD_BYTE_LENGTH_OFFSET) &
 298                         WSPI_CMD_BYTE_LENGTH;
 299                 *cmd |= addr & WSPI_CMD_BYTE_ADDR;
 300
 301                 if (fixed)
 302                         *cmd |= WSPI_CMD_FIXED;
 303
 304                 t[i].tx_buf = cmd;
 305                 t[i].len = sizeof(*cmd);
 306                 spi_message_add_tail(&t[i++], &m);
 307
 308                 t[i].tx_buf = buf;
 309                 t[i].len = chunk_len;
 310                 spi_message_add_tail(&t[i++], &m);
 311
 312                 if (!fixed)
 313                         addr += chunk_len;
 314                 buf += chunk_len;
 315                 len -= chunk_len;
 316                 cmd++;
 317         }
 318
 319         spi_sync(to_spi_device(glue->dev), &m);
 320
 321         return 0;
 322 }
 323
 324 /**
 325  * wl12xx_spi_set_power - power on/off the wl12xx unit
 326  * @child: wl12xx device handle.
 327  * @enable: true/false to power on/off the unit.
 328  *
 329  * use the WiFi enable regulator to enable/disable the WiFi unit.
 330  */
 331 static int wl12xx_spi_set_power(struct device *child, bool enable)
 332 {
 333         int ret = 0;
 334         struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
 335
 336         WARN_ON(!glue->reg);
 337
 338         /* Update regulator state */
 339         if (enable) {
 340                 ret = regulator_enable(glue->reg);
 341                 if (ret)
 342                         dev_err(child, "Power enable failure\n");
 343         } else {
 344                 ret =  regulator_disable(glue->reg);
 345                 if (ret)
 346                         dev_err(child, "Power disable failure\n");
 347         }
 348
 349         return ret;
 350 }
 351
 352 static struct wl1271_if_operations spi_ops = {
 353         .read           = wl12xx_spi_raw_read,
 354         .write          = wl12xx_spi_raw_write,
 355         .reset          = wl12xx_spi_reset,
 356         .init           = wl12xx_spi_init,
 357         .power          = wl12xx_spi_set_power,
 358         .set_block_size = NULL,
 359 };
 360
 361 static const struct of_device_id wlcore_spi_of_match_table[] = {
 362         { .compatible = "ti,wl1271" },
 363         { }
 364 };
 365 MODULE_DEVICE_TABLE(of, wlcore_spi_of_match_table);
 366
 367 /**
 368  * wlcore_probe_of - DT node parsing.
 369  * @spi: SPI slave device parameters.
 370  * @res: resource parameters.
 371  * @glue: wl12xx SPI bus to slave device glue parameters.
 372  * @pdev_data: wlcore device parameters
 373  */
 374 static int wlcore_probe_of(struct spi_device *spi, struct wl12xx_spi_glue *glue,
 375                            struct wlcore_platdev_data *pdev_data)
 376 {
 377         struct device_node *dt_node = spi->dev.of_node;
 378         int ret;
 379
 380         if (of_find_property(dt_node, "clock-xtal", NULL))
 381                 pdev_data->ref_clock_xtal = true;
 382
 383         ret = of_property_read_u32(dt_node, "ref-clock-frequency",
 384                                    &pdev_data->ref_clock_freq);
 385         if (IS_ERR_VALUE(ret)) {
 386                 dev_err(glue->dev,
 387                         "can't get reference clock frequency (%d)\n", ret);
 388                 return ret;
 389         }
 390
 391         return 0;
 392 }
 393
 394 static int wl1271_probe(struct spi_device *spi)
 395 {
 396         struct wl12xx_spi_glue *glue;
 397         struct wlcore_platdev_data pdev_data;
 398         struct resource res[1];
 399         int ret;
 400
 401         memset(&pdev_data, 0x00, sizeof(pdev_data));
 402
 403         pdev_data.if_ops = &spi_ops;
 404
 405         glue = devm_kzalloc(&spi->dev, sizeof(*glue), GFP_KERNEL);
 406         if (!glue) {
 407                 dev_err(&spi->dev, "can't allocate glue\n");
 408                 return -ENOMEM;
 409         }
 410
 411         glue->dev = &spi->dev;
 412
 413         spi_set_drvdata(spi, glue);
 414
 415         /* This is the only SPI value that we need to set here, the rest
 416          * comes from the board-peripherals file */
 417         spi->bits_per_word = 32;
 418
 419         glue->reg = devm_regulator_get(&spi->dev, "vwlan");
 420         if (PTR_ERR(glue->reg) == -EPROBE_DEFER)
 421                 return -EPROBE_DEFER;
 422         if (IS_ERR(glue->reg)) {
 423                 dev_err(glue->dev, "can't get regulator\n");
 424                 return PTR_ERR(glue->reg);
 425         }
 426
 427         ret = wlcore_probe_of(spi, glue, &pdev_data);
 428         if (IS_ERR_VALUE(ret)) {
 429                 dev_err(glue->dev,
 430                         "can't get device tree parameters (%d)\n", ret);
 431                 return ret;
 432         }
 433
 434         ret = spi_setup(spi);
 435         if (ret < 0) {
 436                 dev_err(glue->dev, "spi_setup failed\n");
 437                 return ret;
 438         }
 439
 440         glue->core = platform_device_alloc("wl12xx", PLATFORM_DEVID_AUTO);
 441         if (!glue->core) {
 442                 dev_err(glue->dev, "can't allocate platform_device\n");
 443                 return -ENOMEM;
 444         }
 445
 446         glue->core->dev.parent = &spi->dev;
 447
 448         memset(res, 0x00, sizeof(res));
 449
 450         res[0].start = spi->irq;
 451         res[0].flags = IORESOURCE_IRQ | irq_get_trigger_type(spi->irq);
 452         res[0].name = "irq";
 453
 454         ret = platform_device_add_resources(glue->core, res, ARRAY_SIZE(res));
 455         if (ret) {
 456                 dev_err(glue->dev, "can't add resources\n");
 457                 goto out_dev_put;
 458         }
 459
 460         ret = platform_device_add_data(glue->core, &pdev_data,
 461                                        sizeof(pdev_data));
 462         if (ret) {
 463                 dev_err(glue->dev, "can't add platform data\n");
 464                 goto out_dev_put;
 465         }
 466
 467         ret = platform_device_add(glue->core);
 468         if (ret) {
 469                 dev_err(glue->dev, "can't register platform device\n");
 470                 goto out_dev_put;
 471         }
 472
 473         return 0;
 474
 475 out_dev_put:
 476         platform_device_put(glue->core);
 477         return ret;
 478 }
 479
 480 static int wl1271_remove(struct spi_device *spi)
 481 {
 482         struct wl12xx_spi_glue *glue = spi_get_drvdata(spi);
 483
 484         platform_device_unregister(glue->core);
 485
 486         return 0;
 487 }
 488
 489 static struct spi_driver wl1271_spi_driver = {
 490         .driver = {
 491                 .name           = "wl1271_spi",
 492                 .of_match_table = of_match_ptr(wlcore_spi_of_match_table),
 493         },
 494
 495         .probe          = wl1271_probe,
 496         .remove         = wl1271_remove,
 497 };
 498
 499 module_spi_driver(wl1271_spi_driver);
 500 MODULE_LICENSE("GPL");
 501 MODULE_AUTHOR("Luciano Coelho <coelho@ti.com>");
 502 MODULE_AUTHOR("Juuso Oikarinen <juuso.oikarinen@nokia.com>");
 503 MODULE_ALIAS("spi:wl1271");