drivers/net/wireless/ti/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         kfree(cmd);
  78 }
  79
  80 static void wl1251_spi_wake(struct wl1251 *wl)
  81 {
  82         u8 crc[WSPI_INIT_CMD_CRC_LEN], *cmd;
  83         struct spi_transfer t;
  84         struct spi_message m;
  85
  86         cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
  87         if (!cmd) {
  88                 wl1251_error("could not allocate cmd for spi init");
  89                 return;
  90         }
  91
  92         memset(crc, 0, sizeof(crc));
  93         memset(&t, 0, sizeof(t));
  94         spi_message_init(&m);
  95
  96         /*
  97          * Set WSPI_INIT_COMMAND
  98          * the data is being send from the MSB to LSB
  99          */
 100         cmd[2] = 0xff;
 101         cmd[3] = 0xff;
 102         cmd[1] = WSPI_INIT_CMD_START | WSPI_INIT_CMD_TX;
 103         cmd[0] = 0;
 104         cmd[7] = 0;
 105         cmd[6] |= HW_ACCESS_WSPI_INIT_CMD_MASK << 3;
 106         cmd[6] |= HW_ACCESS_WSPI_FIXED_BUSY_LEN & WSPI_INIT_CMD_FIXEDBUSY_LEN;
 107
 108         if (HW_ACCESS_WSPI_FIXED_BUSY_LEN == 0)
 109                 cmd[5] |=  WSPI_INIT_CMD_DIS_FIXEDBUSY;
 110         else
 111                 cmd[5] |= WSPI_INIT_CMD_EN_FIXEDBUSY;
 112
 113         cmd[5] |= WSPI_INIT_CMD_IOD | WSPI_INIT_CMD_IP | WSPI_INIT_CMD_CS
 114                 | WSPI_INIT_CMD_WSPI | WSPI_INIT_CMD_WS;
 115
 116         crc[0] = cmd[1];
 117         crc[1] = cmd[0];
 118         crc[2] = cmd[7];
 119         crc[3] = cmd[6];
 120         crc[4] = cmd[5];
 121
 122         cmd[4] |= crc7(0, crc, WSPI_INIT_CMD_CRC_LEN) << 1;
 123         cmd[4] |= WSPI_INIT_CMD_END;
 124
 125         t.tx_buf = cmd;
 126         t.len = WSPI_INIT_CMD_LEN;
 127         spi_message_add_tail(&t, &m);
 128
 129         spi_sync(wl_to_spi(wl), &m);
 130
 131         wl1251_dump(DEBUG_SPI, "spi init -> ", cmd, WSPI_INIT_CMD_LEN);
 132
 133         kfree(cmd);
 134 }
 135
 136 static void wl1251_spi_reset_wake(struct wl1251 *wl)
 137 {
 138         wl1251_spi_reset(wl);
 139         wl1251_spi_wake(wl);
 140 }
 141
 142 static void wl1251_spi_read(struct wl1251 *wl, int addr, void *buf,
 143                             size_t len)
 144 {
 145         struct spi_transfer t[3];
 146         struct spi_message m;
 147         u8 *busy_buf;
 148         u32 *cmd;
 149
 150         cmd = &wl->buffer_cmd;
 151         busy_buf = wl->buffer_busyword;
 152
 153         *cmd = 0;
 154         *cmd |= WSPI_CMD_READ;
 155         *cmd |= (len << WSPI_CMD_BYTE_LENGTH_OFFSET) & WSPI_CMD_BYTE_LENGTH;
 156         *cmd |= addr & WSPI_CMD_BYTE_ADDR;
 157
 158         spi_message_init(&m);
 159         memset(t, 0, sizeof(t));
 160
 161         t[0].tx_buf = cmd;
 162         t[0].len = 4;
 163         spi_message_add_tail(&t[0], &m);
 164
 165         /* Busy and non busy words read */
 166         t[1].rx_buf = busy_buf;
 167         t[1].len = WL1251_BUSY_WORD_LEN;
 168         spi_message_add_tail(&t[1], &m);
 169
 170         t[2].rx_buf = buf;
 171         t[2].len = len;
 172         spi_message_add_tail(&t[2], &m);
 173
 174         spi_sync(wl_to_spi(wl), &m);
 175
 176         /* FIXME: check busy words */
 177
 178         wl1251_dump(DEBUG_SPI, "spi_read cmd -> ", cmd, sizeof(*cmd));
 179         wl1251_dump(DEBUG_SPI, "spi_read buf <- ", buf, len);
 180 }
 181
 182 static void wl1251_spi_write(struct wl1251 *wl, int addr, void *buf,
 183                              size_t len)
 184 {
 185         struct spi_transfer t[2];
 186         struct spi_message m;
 187         u32 *cmd;
 188
 189         cmd = &wl->buffer_cmd;
 190
 191         *cmd = 0;
 192         *cmd |= WSPI_CMD_WRITE;
 193         *cmd |= (len << WSPI_CMD_BYTE_LENGTH_OFFSET) & WSPI_CMD_BYTE_LENGTH;
 194         *cmd |= addr & WSPI_CMD_BYTE_ADDR;
 195
 196         spi_message_init(&m);
 197         memset(t, 0, sizeof(t));
 198
 199         t[0].tx_buf = cmd;
 200         t[0].len = sizeof(*cmd);
 201         spi_message_add_tail(&t[0], &m);
 202
 203         t[1].tx_buf = buf;
 204         t[1].len = len;
 205         spi_message_add_tail(&t[1], &m);
 206
 207         spi_sync(wl_to_spi(wl), &m);
 208
 209         wl1251_dump(DEBUG_SPI, "spi_write cmd -> ", cmd, sizeof(*cmd));
 210         wl1251_dump(DEBUG_SPI, "spi_write buf -> ", buf, len);
 211 }
 212
 213 static void wl1251_spi_enable_irq(struct wl1251 *wl)
 214 {
 215         return enable_irq(wl->irq);
 216 }
 217
 218 static void wl1251_spi_disable_irq(struct wl1251 *wl)
 219 {
 220         return disable_irq(wl->irq);
 221 }
 222
 223 static int wl1251_spi_set_power(struct wl1251 *wl, bool enable)
 224 {
 225         if (wl->set_power)
 226                 wl->set_power(enable);
 227
 228         return 0;
 229 }
 230
 231 static const struct wl1251_if_operations wl1251_spi_ops = {
 232         .read = wl1251_spi_read,
 233         .write = wl1251_spi_write,
 234         .reset = wl1251_spi_reset_wake,
 235         .enable_irq = wl1251_spi_enable_irq,
 236         .disable_irq = wl1251_spi_disable_irq,
 237         .power = wl1251_spi_set_power,
 238 };
 239
 240 static int __devinit wl1251_spi_probe(struct spi_device *spi)
 241 {
 242         struct wl12xx_platform_data *pdata;
 243         struct ieee80211_hw *hw;
 244         struct wl1251 *wl;
 245         int ret;
 246
 247         pdata = spi->dev.platform_data;
 248         if (!pdata) {
 249                 wl1251_error("no platform data");
 250                 return -ENODEV;
 251         }
 252
 253         hw = wl1251_alloc_hw();
 254         if (IS_ERR(hw))
 255                 return PTR_ERR(hw);
 256
 257         wl = hw->priv;
 258
 259         SET_IEEE80211_DEV(hw, &spi->dev);
 260         dev_set_drvdata(&spi->dev, wl);
 261         wl->if_priv = spi;
 262         wl->if_ops = &wl1251_spi_ops;
 263
 264         /* This is the only SPI value that we need to set here, the rest
 265          * comes from the board-peripherals file */
 266         spi->bits_per_word = 32;
 267
 268         ret = spi_setup(spi);
 269         if (ret < 0) {
 270                 wl1251_error("spi_setup failed");
 271                 goto out_free;
 272         }
 273
 274         wl->set_power = pdata->set_power;
 275         if (!wl->set_power) {
 276                 wl1251_error("set power function missing in platform data");
 277                 return -ENODEV;
 278         }
 279
 280         wl->irq = spi->irq;
 281         if (wl->irq < 0) {
 282                 wl1251_error("irq missing in platform data");
 283                 return -ENODEV;
 284         }
 285
 286         wl->use_eeprom = pdata->use_eeprom;
 287
 288         irq_set_status_flags(wl->irq, IRQ_NOAUTOEN);
 289         ret = request_irq(wl->irq, wl1251_irq, 0, DRIVER_NAME, wl);
 290         if (ret < 0) {
 291                 wl1251_error("request_irq() failed: %d", ret);
 292                 goto out_free;
 293         }
 294
 295         irq_set_irq_type(wl->irq, IRQ_TYPE_EDGE_RISING);
 296
 297         ret = wl1251_init_ieee80211(wl);
 298         if (ret)
 299                 goto out_irq;
 300
 301         return 0;
 302
 303  out_irq:
 304         free_irq(wl->irq, wl);
 305
 306  out_free:
 307         ieee80211_free_hw(hw);
 308
 309         return ret;
 310 }
 311
 312 static int __devexit wl1251_spi_remove(struct spi_device *spi)
 313 {
 314         struct wl1251 *wl = dev_get_drvdata(&spi->dev);
 315
 316         free_irq(wl->irq, wl);
 317         wl1251_free_hw(wl);
 318
 319         return 0;
 320 }
 321
 322 static struct spi_driver wl1251_spi_driver = {
 323         .driver = {
 324                 .name           = DRIVER_NAME,
 325                 .owner          = THIS_MODULE,
 326         },
 327
 328         .probe          = wl1251_spi_probe,
 329         .remove         = __devexit_p(wl1251_spi_remove),
 330 };
 331
 332 static int __init wl1251_spi_init(void)
 333 {
 334         int ret;
 335
 336         ret = spi_register_driver(&wl1251_spi_driver);
 337         if (ret < 0) {
 338                 wl1251_error("failed to register spi driver: %d", ret);
 339                 goto out;
 340         }
 341
 342 out:
 343         return ret;
 344 }
 345
 346 static void __exit wl1251_spi_exit(void)
 347 {
 348         spi_unregister_driver(&wl1251_spi_driver);
 349
 350         wl1251_notice("unloaded");
 351 }
 352
 353 module_init(wl1251_spi_init);
 354 module_exit(wl1251_spi_exit);
 355
 356 MODULE_LICENSE("GPL");
 357 MODULE_AUTHOR("Kalle Valo <kvalo@adurom.com>");
 358 MODULE_ALIAS("spi:wl1251");