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/irq.h>
  23 #include <linux/module.h>
  24 #include <linux/slab.h>
  25 #include <linux/crc7.h>
  26 #include <linux/spi/spi.h>
  27 #include <linux/wl12xx.h>
  28
  29 #include "wl1251.h"
  30 #include "reg.h"
  31 #include "spi.h"
  32
  33 static irqreturn_t wl1251_irq(int irq, void *cookie)
  34 {
  35         struct wl1251 *wl;
  36
  37         wl1251_debug(DEBUG_IRQ, "IRQ");
  38
  39         wl = cookie;
  40
  41         ieee80211_queue_work(wl->hw, &wl->irq_work);
  42
  43         return IRQ_HANDLED;
  44 }
  45
  46 static struct spi_device *wl_to_spi(struct wl1251 *wl)
  47 {
  48         return wl->if_priv;
  49 }
  50
  51 static void wl1251_spi_reset(struct wl1251 *wl)
  52 {
  53         u8 *cmd;
  54         struct spi_transfer t;
  55         struct spi_message m;
  56
  57         cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
  58         if (!cmd) {
  59                 wl1251_error("could not allocate cmd for spi reset");
  60                 return;
  61         }
  62
  63         memset(&t, 0, sizeof(t));
  64         spi_message_init(&m);
  65
  66         memset(cmd, 0xff, WSPI_INIT_CMD_LEN);
  67
  68         t.tx_buf = cmd;
  69         t.len = WSPI_INIT_CMD_LEN;
  70         spi_message_add_tail(&t, &m);
  71
  72         spi_sync(wl_to_spi(wl), &m);
  73
  74         wl1251_dump(DEBUG_SPI, "spi reset -> ", cmd, WSPI_INIT_CMD_LEN);
  75 }
  76
  77 static void wl1251_spi_wake(struct wl1251 *wl)
  78 {
  79         u8 crc[WSPI_INIT_CMD_CRC_LEN], *cmd;
  80         struct spi_transfer t;
  81         struct spi_message m;
  82
  83         cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
  84         if (!cmd) {
  85                 wl1251_error("could not allocate cmd for spi init");
  86                 return;
  87         }
  88
  89         memset(crc, 0, sizeof(crc));
  90         memset(&t, 0, sizeof(t));
  91         spi_message_init(&m);
  92
  93         /*
  94          * Set WSPI_INIT_COMMAND
  95          * the data is being send from the MSB to LSB
  96          */
  97         cmd[2] = 0xff;
  98         cmd[3] = 0xff;
  99         cmd[1] = WSPI_INIT_CMD_START | WSPI_INIT_CMD_TX;
 100         cmd[0] = 0;
 101         cmd[7] = 0;
 102         cmd[6] |= HW_ACCESS_WSPI_INIT_CMD_MASK << 3;
 103         cmd[6] |= HW_ACCESS_WSPI_FIXED_BUSY_LEN & WSPI_INIT_CMD_FIXEDBUSY_LEN;
 104
 105         if (HW_ACCESS_WSPI_FIXED_BUSY_LEN == 0)
 106                 cmd[5] |=  WSPI_INIT_CMD_DIS_FIXEDBUSY;
 107         else
 108                 cmd[5] |= WSPI_INIT_CMD_EN_FIXEDBUSY;
 109
 110         cmd[5] |= WSPI_INIT_CMD_IOD | WSPI_INIT_CMD_IP | WSPI_INIT_CMD_CS
 111                 | WSPI_INIT_CMD_WSPI | WSPI_INIT_CMD_WS;
 112
 113         crc[0] = cmd[1];
 114         crc[1] = cmd[0];
 115         crc[2] = cmd[7];
 116         crc[3] = cmd[6];
 117         crc[4] = cmd[5];
 118
 119         cmd[4] |= crc7(0, crc, WSPI_INIT_CMD_CRC_LEN) << 1;
 120         cmd[4] |= WSPI_INIT_CMD_END;
 121
 122         t.tx_buf = cmd;
 123         t.len = WSPI_INIT_CMD_LEN;
 124         spi_message_add_tail(&t, &m);
 125
 126         spi_sync(wl_to_spi(wl), &m);
 127
 128         wl1251_dump(DEBUG_SPI, "spi init -> ", cmd, WSPI_INIT_CMD_LEN);
 129 }
 130
 131 static void wl1251_spi_reset_wake(struct wl1251 *wl)
 132 {
 133         wl1251_spi_reset(wl);
 134         wl1251_spi_wake(wl);
 135 }
 136
 137 static void wl1251_spi_read(struct wl1251 *wl, int addr, void *buf,
 138                             size_t len)
 139 {
 140         struct spi_transfer t[3];
 141         struct spi_message m;
 142         u8 *busy_buf;
 143         u32 *cmd;
 144
 145         cmd = &wl->buffer_cmd;
 146         busy_buf = wl->buffer_busyword;
 147
 148         *cmd = 0;
 149         *cmd |= WSPI_CMD_READ;
 150         *cmd |= (len << WSPI_CMD_BYTE_LENGTH_OFFSET) & WSPI_CMD_BYTE_LENGTH;
 151         *cmd |= addr & WSPI_CMD_BYTE_ADDR;
 152
 153         spi_message_init(&m);
 154         memset(t, 0, sizeof(t));
 155
 156         t[0].tx_buf = cmd;
 157         t[0].len = 4;
 158         spi_message_add_tail(&t[0], &m);
 159
 160         /* Busy and non busy words read */
 161         t[1].rx_buf = busy_buf;
 162         t[1].len = WL1251_BUSY_WORD_LEN;
 163         spi_message_add_tail(&t[1], &m);
 164
 165         t[2].rx_buf = buf;
 166         t[2].len = len;
 167         spi_message_add_tail(&t[2], &m);
 168
 169         spi_sync(wl_to_spi(wl), &m);
 170
 171         /* FIXME: check busy words */
 172
 173         wl1251_dump(DEBUG_SPI, "spi_read cmd -> ", cmd, sizeof(*cmd));
 174         wl1251_dump(DEBUG_SPI, "spi_read buf <- ", buf, len);
 175 }
 176
 177 static void wl1251_spi_write(struct wl1251 *wl, int addr, void *buf,
 178                              size_t len)
 179 {
 180         struct spi_transfer t[2];
 181         struct spi_message m;
 182         u32 *cmd;
 183
 184         cmd = &wl->buffer_cmd;
 185
 186         *cmd = 0;
 187         *cmd |= WSPI_CMD_WRITE;
 188         *cmd |= (len << WSPI_CMD_BYTE_LENGTH_OFFSET) & WSPI_CMD_BYTE_LENGTH;
 189         *cmd |= addr & WSPI_CMD_BYTE_ADDR;
 190
 191         spi_message_init(&m);
 192         memset(t, 0, sizeof(t));
 193
 194         t[0].tx_buf = cmd;
 195         t[0].len = sizeof(*cmd);
 196         spi_message_add_tail(&t[0], &m);
 197
 198         t[1].tx_buf = buf;
 199         t[1].len = len;
 200         spi_message_add_tail(&t[1], &m);
 201
 202         spi_sync(wl_to_spi(wl), &m);
 203
 204         wl1251_dump(DEBUG_SPI, "spi_write cmd -> ", cmd, sizeof(*cmd));
 205         wl1251_dump(DEBUG_SPI, "spi_write buf -> ", buf, len);
 206 }
 207
 208 static void wl1251_spi_enable_irq(struct wl1251 *wl)
 209 {
 210         return enable_irq(wl->irq);
 211 }
 212
 213 static void wl1251_spi_disable_irq(struct wl1251 *wl)
 214 {
 215         return disable_irq(wl->irq);
 216 }
 217
 218 static const struct wl1251_if_operations wl1251_spi_ops = {
 219         .read = wl1251_spi_read,
 220         .write = wl1251_spi_write,
 221         .reset = wl1251_spi_reset_wake,
 222         .enable_irq = wl1251_spi_enable_irq,
 223         .disable_irq = wl1251_spi_disable_irq,
 224 };
 225
 226 static int __devinit wl1251_spi_probe(struct spi_device *spi)
 227 {
 228         struct wl12xx_platform_data *pdata;
 229         struct ieee80211_hw *hw;
 230         struct wl1251 *wl;
 231         int ret;
 232
 233         pdata = spi->dev.platform_data;
 234         if (!pdata) {
 235                 wl1251_error("no platform data");
 236                 return -ENODEV;
 237         }
 238
 239         hw = wl1251_alloc_hw();
 240         if (IS_ERR(hw))
 241                 return PTR_ERR(hw);
 242
 243         wl = hw->priv;
 244
 245         SET_IEEE80211_DEV(hw, &spi->dev);
 246         dev_set_drvdata(&spi->dev, wl);
 247         wl->if_priv = spi;
 248         wl->if_ops = &wl1251_spi_ops;
 249
 250         /* This is the only SPI value that we need to set here, the rest
 251          * comes from the board-peripherals file */
 252         spi->bits_per_word = 32;
 253
 254         ret = spi_setup(spi);
 255         if (ret < 0) {
 256                 wl1251_error("spi_setup failed");
 257                 goto out_free;
 258         }
 259
 260         wl->set_power = pdata->set_power;
 261         if (!wl->set_power) {
 262                 wl1251_error("set power function missing in platform data");
 263                 return -ENODEV;
 264         }
 265
 266         wl->irq = spi->irq;
 267         if (wl->irq < 0) {
 268                 wl1251_error("irq missing in platform data");
 269                 return -ENODEV;
 270         }
 271
 272         wl->use_eeprom = pdata->use_eeprom;
 273
 274         ret = request_irq(wl->irq, wl1251_irq, 0, DRIVER_NAME, wl);
 275         if (ret < 0) {
 276                 wl1251_error("request_irq() failed: %d", ret);
 277                 goto out_free;
 278         }
 279
 280         set_irq_type(wl->irq, IRQ_TYPE_EDGE_RISING);
 281
 282         disable_irq(wl->irq);
 283
 284         ret = wl1251_init_ieee80211(wl);
 285         if (ret)
 286                 goto out_irq;
 287
 288         return 0;
 289
 290  out_irq:
 291         free_irq(wl->irq, wl);
 292
 293  out_free:
 294         ieee80211_free_hw(hw);
 295
 296         return ret;
 297 }
 298
 299 static int __devexit wl1251_spi_remove(struct spi_device *spi)
 300 {
 301         struct wl1251 *wl = dev_get_drvdata(&spi->dev);
 302
 303         free_irq(wl->irq, wl);
 304         wl1251_free_hw(wl);
 305
 306         return 0;
 307 }
 308
 309 static struct spi_driver wl1251_spi_driver = {
 310         .driver = {
 311                 .name           = DRIVER_NAME,
 312                 .bus            = &spi_bus_type,
 313                 .owner          = THIS_MODULE,
 314         },
 315
 316         .probe          = wl1251_spi_probe,
 317         .remove         = __devexit_p(wl1251_spi_remove),
 318 };
 319
 320 static int __init wl1251_spi_init(void)
 321 {
 322         int ret;
 323
 324         ret = spi_register_driver(&wl1251_spi_driver);
 325         if (ret < 0) {
 326                 wl1251_error("failed to register spi driver: %d", ret);
 327                 goto out;
 328         }
 329
 330 out:
 331         return ret;
 332 }
 333
 334 static void __exit wl1251_spi_exit(void)
 335 {
 336         spi_unregister_driver(&wl1251_spi_driver);
 337
 338         wl1251_notice("unloaded");
 339 }
 340
 341 module_init(wl1251_spi_init);
 342 module_exit(wl1251_spi_exit);
 343
 344 MODULE_LICENSE("GPL");
 345 MODULE_AUTHOR("Kalle Valo <kvalo@adurom.com>");
 346 MODULE_ALIAS("spi:wl1251");