drivers/net/wireless/wl1251/spi.c

   1 /*
   2  * This file is part of wl1251
   3  *
   4  * Copyright (C) 2008 Nokia Corporation
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * version 2 as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
  18  * 02110-1301 USA
  19  *
  20  */
  21
  22 #include <linux/interrupt.h>
  23 #include <linux/irq.h>
  24 #include <linux/module.h>
  25 #include <linux/slab.h>
  26 #include <linux/crc7.h>
  27 #include <linux/spi/spi.h>
  28 #include <linux/wl12xx.h>
  29
  30 #include "wl1251.h"
  31 #include "reg.h"
  32 #include "spi.h"
  33
  34 static irqreturn_t wl1251_irq(int irq, void *cookie)
  35 {
  36         struct wl1251 *wl;
  37
  38         wl1251_debug(DEBUG_IRQ, "IRQ");
  39
  40         wl = cookie;
  41
  42         ieee80211_queue_work(wl->hw, &wl->irq_work);
  43
  44         return IRQ_HANDLED;
  45 }
  46
  47 static struct spi_device *wl_to_spi(struct wl1251 *wl)
  48 {
  49         return wl->if_priv;
  50 }
  51
  52 static void wl1251_spi_reset(struct wl1251 *wl)
  53 {
  54         u8 *cmd;
  55         struct spi_transfer t;
  56         struct spi_message m;
  57
  58         cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
  59         if (!cmd) {
  60                 wl1251_error("could not allocate cmd for spi reset");
  61                 return;
  62         }
  63
  64         memset(&t, 0, sizeof(t));
  65         spi_message_init(&m);
  66
  67         memset(cmd, 0xff, WSPI_INIT_CMD_LEN);
  68
  69         t.tx_buf = cmd;
  70         t.len = WSPI_INIT_CMD_LEN;
  71         spi_message_add_tail(&t, &m);
  72
  73         spi_sync(wl_to_spi(wl), &m);
  74
  75         wl1251_dump(DEBUG_SPI, "spi reset -> ", cmd, WSPI_INIT_CMD_LEN);
  76 }
  77
  78 static void wl1251_spi_wake(struct wl1251 *wl)
  79 {
  80         u8 crc[WSPI_INIT_CMD_CRC_LEN], *cmd;
  81         struct spi_transfer t;
  82         struct spi_message m;
  83
  84         cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
  85         if (!cmd) {
  86                 wl1251_error("could not allocate cmd for spi init");
  87                 return;
  88         }
  89
  90         memset(crc, 0, sizeof(crc));
  91         memset(&t, 0, sizeof(t));
  92         spi_message_init(&m);
  93
  94         /*
  95          * Set WSPI_INIT_COMMAND
  96          * the data is being send from the MSB to LSB
  97          */
  98         cmd[2] = 0xff;
  99         cmd[3] = 0xff;
 100         cmd[1] = WSPI_INIT_CMD_START | WSPI_INIT_CMD_TX;
 101         cmd[0] = 0;
 102         cmd[7] = 0;
 103         cmd[6] |= HW_ACCESS_WSPI_INIT_CMD_MASK << 3;
 104         cmd[6] |= HW_ACCESS_WSPI_FIXED_BUSY_LEN & WSPI_INIT_CMD_FIXEDBUSY_LEN;
 105
 106         if (HW_ACCESS_WSPI_FIXED_BUSY_LEN == 0)
 107                 cmd[5] |=  WSPI_INIT_CMD_DIS_FIXEDBUSY;
 108         else
 109                 cmd[5] |= WSPI_INIT_CMD_EN_FIXEDBUSY;
 110
 111         cmd[5] |= WSPI_INIT_CMD_IOD | WSPI_INIT_CMD_IP | WSPI_INIT_CMD_CS
 112                 | WSPI_INIT_CMD_WSPI | WSPI_INIT_CMD_WS;
 113
 114         crc[0] = cmd[1];
 115         crc[1] = cmd[0];
 116         crc[2] = cmd[7];
 117         crc[3] = cmd[6];
 118         crc[4] = cmd[5];
 119
 120         cmd[4] |= crc7(0, crc, WSPI_INIT_CMD_CRC_LEN) << 1;
 121         cmd[4] |= WSPI_INIT_CMD_END;
 122
 123         t.tx_buf = cmd;
 124         t.len = WSPI_INIT_CMD_LEN;
 125         spi_message_add_tail(&t, &m);
 126
 127         spi_sync(wl_to_spi(wl), &m);
 128
 129         wl1251_dump(DEBUG_SPI, "spi init -> ", cmd, WSPI_INIT_CMD_LEN);
 130 }
 131
 132 static void wl1251_spi_reset_wake(struct wl1251 *wl)
 133 {
 134         wl1251_spi_reset(wl);
 135         wl1251_spi_wake(wl);
 136 }
 137
 138 static void wl1251_spi_read(struct wl1251 *wl, int addr, void *buf,
 139                             size_t len)
 140 {
 141         struct spi_transfer t[3];
 142         struct spi_message m;
 143         u8 *busy_buf;
 144         u32 *cmd;
 145
 146         cmd = &wl->buffer_cmd;
 147         busy_buf = wl->buffer_busyword;
 148
 149         *cmd = 0;
 150         *cmd |= WSPI_CMD_READ;
 151         *cmd |= (len << WSPI_CMD_BYTE_LENGTH_OFFSET) & WSPI_CMD_BYTE_LENGTH;
 152         *cmd |= addr & WSPI_CMD_BYTE_ADDR;
 153
 154         spi_message_init(&m);
 155         memset(t, 0, sizeof(t));
 156
 157         t[0].tx_buf = cmd;
 158         t[0].len = 4;
 159         spi_message_add_tail(&t[0], &m);
 160
 161         /* Busy and non busy words read */
 162         t[1].rx_buf = busy_buf;
 163         t[1].len = WL1251_BUSY_WORD_LEN;
 164         spi_message_add_tail(&t[1], &m);
 165
 166         t[2].rx_buf = buf;
 167         t[2].len = len;
 168         spi_message_add_tail(&t[2], &m);
 169
 170         spi_sync(wl_to_spi(wl), &m);
 171
 172         /* FIXME: check busy words */
 173
 174         wl1251_dump(DEBUG_SPI, "spi_read cmd -> ", cmd, sizeof(*cmd));
 175         wl1251_dump(DEBUG_SPI, "spi_read buf <- ", buf, len);
 176 }
 177
 178 static void wl1251_spi_write(struct wl1251 *wl, int addr, void *buf,
 179                              size_t len)
 180 {
 181         struct spi_transfer t[2];
 182         struct spi_message m;
 183         u32 *cmd;
 184
 185         cmd = &wl->buffer_cmd;
 186
 187         *cmd = 0;
 188         *cmd |= WSPI_CMD_WRITE;
 189         *cmd |= (len << WSPI_CMD_BYTE_LENGTH_OFFSET) & WSPI_CMD_BYTE_LENGTH;
 190         *cmd |= addr & WSPI_CMD_BYTE_ADDR;
 191
 192         spi_message_init(&m);
 193         memset(t, 0, sizeof(t));
 194
 195         t[0].tx_buf = cmd;
 196         t[0].len = sizeof(*cmd);
 197         spi_message_add_tail(&t[0], &m);
 198
 199         t[1].tx_buf = buf;
 200         t[1].len = len;
 201         spi_message_add_tail(&t[1], &m);
 202
 203         spi_sync(wl_to_spi(wl), &m);
 204
 205         wl1251_dump(DEBUG_SPI, "spi_write cmd -> ", cmd, sizeof(*cmd));
 206         wl1251_dump(DEBUG_SPI, "spi_write buf -> ", buf, len);
 207 }
 208
 209 static void wl1251_spi_enable_irq(struct wl1251 *wl)
 210 {
 211         return enable_irq(wl->irq);
 212 }
 213
 214 static void wl1251_spi_disable_irq(struct wl1251 *wl)
 215 {
 216         return disable_irq(wl->irq);
 217 }
 218
 219 static int wl1251_spi_set_power(struct wl1251 *wl, bool enable)
 220 {
 221         if (wl->set_power)
 222                 wl->set_power(enable);
 223
 224         return 0;
 225 }
 226
 227 static const struct wl1251_if_operations wl1251_spi_ops = {
 228         .read = wl1251_spi_read,
 229         .write = wl1251_spi_write,
 230         .reset = wl1251_spi_reset_wake,
 231         .enable_irq = wl1251_spi_enable_irq,
 232         .disable_irq = wl1251_spi_disable_irq,
 233         .power = wl1251_spi_set_power,
 234 };
 235
 236 static int __devinit wl1251_spi_probe(struct spi_device *spi)
 237 {
 238         struct wl12xx_platform_data *pdata;
 239         struct ieee80211_hw *hw;
 240         struct wl1251 *wl;
 241         int ret;
 242
 243         pdata = spi->dev.platform_data;
 244         if (!pdata) {
 245                 wl1251_error("no platform data");
 246                 return -ENODEV;
 247         }
 248
 249         hw = wl1251_alloc_hw();
 250         if (IS_ERR(hw))
 251                 return PTR_ERR(hw);
 252
 253         wl = hw->priv;
 254
 255         SET_IEEE80211_DEV(hw, &spi->dev);
 256         dev_set_drvdata(&spi->dev, wl);
 257         wl->if_priv = spi;
 258         wl->if_ops = &wl1251_spi_ops;
 259
 260         /* This is the only SPI value that we need to set here, the rest
 261          * comes from the board-peripherals file */
 262         spi->bits_per_word = 32;
 263
 264         ret = spi_setup(spi);
 265         if (ret < 0) {
 266                 wl1251_error("spi_setup failed");
 267                 goto out_free;
 268         }
 269
 270         wl->set_power = pdata->set_power;
 271         if (!wl->set_power) {
 272                 wl1251_error("set power function missing in platform data");
 273                 return -ENODEV;
 274         }
 275
 276         wl->irq = spi->irq;
 277         if (wl->irq < 0) {
 278                 wl1251_error("irq missing in platform data");
 279                 return -ENODEV;
 280         }
 281
 282         wl->use_eeprom = pdata->use_eeprom;
 283
 284         ret = request_irq(wl->irq, wl1251_irq, 0, DRIVER_NAME, wl);
 285         if (ret < 0) {
 286                 wl1251_error("request_irq() failed: %d", ret);
 287                 goto out_free;
 288         }
 289
 290         irq_set_irq_type(wl->irq, IRQ_TYPE_EDGE_RISING);
 291
 292         disable_irq(wl->irq);
 293
 294         ret = wl1251_init_ieee80211(wl);
 295         if (ret)
 296                 goto out_irq;
 297
 298         return 0;
 299
 300  out_irq:
 301         free_irq(wl->irq, wl);
 302
 303  out_free:
 304         ieee80211_free_hw(hw);
 305
 306         return ret;
 307 }
 308
 309 static int __devexit wl1251_spi_remove(struct spi_device *spi)
 310 {
 311         struct wl1251 *wl = dev_get_drvdata(&spi->dev);
 312
 313         free_irq(wl->irq, wl);
 314         wl1251_free_hw(wl);
 315
 316         return 0;
 317 }
 318
 319 static struct spi_driver wl1251_spi_driver = {
 320         .driver = {
 321                 .name           = DRIVER_NAME,
 322                 .bus            = &spi_bus_type,
 323                 .owner          = THIS_MODULE,
 324         },
 325
 326         .probe          = wl1251_spi_probe,
 327         .remove         = __devexit_p(wl1251_spi_remove),
 328 };
 329
 330 static int __init wl1251_spi_init(void)
 331 {
 332         int ret;
 333
 334         ret = spi_register_driver(&wl1251_spi_driver);
 335         if (ret < 0) {
 336                 wl1251_error("failed to register spi driver: %d", ret);
 337                 goto out;
 338         }
 339
 340 out:
 341         return ret;
 342 }
 343
 344 static void __exit wl1251_spi_exit(void)
 345 {
 346         spi_unregister_driver(&wl1251_spi_driver);
 347
 348         wl1251_notice("unloaded");
 349 }
 350
 351 module_init(wl1251_spi_init);
 352 module_exit(wl1251_spi_exit);
 353
 354 MODULE_LICENSE("GPL");
 355 MODULE_AUTHOR("Kalle Valo <kvalo@adurom.com>");
 356 MODULE_ALIAS("spi:wl1251");