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/swab.h>
  27 #include <linux/crc7.h>
  28 #include <linux/spi/spi.h>
  29 #include <linux/wl12xx.h>
  30 #include <linux/gpio.h>
  31 #include <linux/of.h>
  32 #include <linux/of_gpio.h>
  33 #include <linux/regulator/consumer.h>
  34
  35 #include "wl1251.h"
  36 #include "reg.h"
  37 #include "spi.h"
  38
  39 static irqreturn_t wl1251_irq(int irq, void *cookie)
  40 {
  41         struct wl1251 *wl;
  42
  43         wl1251_debug(DEBUG_IRQ, "IRQ");
  44
  45         wl = cookie;
  46
  47         ieee80211_queue_work(wl->hw, &wl->irq_work);
  48
  49         return IRQ_HANDLED;
  50 }
  51
  52 static struct spi_device *wl_to_spi(struct wl1251 *wl)
  53 {
  54         return wl->if_priv;
  55 }
  56
  57 static void wl1251_spi_reset(struct wl1251 *wl)
  58 {
  59         u8 *cmd;
  60         struct spi_transfer t;
  61         struct spi_message m;
  62
  63         cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
  64         if (!cmd) {
  65                 wl1251_error("could not allocate cmd for spi reset");
  66                 return;
  67         }
  68
  69         memset(&t, 0, sizeof(t));
  70         spi_message_init(&m);
  71
  72         memset(cmd, 0xff, WSPI_INIT_CMD_LEN);
  73
  74         t.tx_buf = cmd;
  75         t.len = WSPI_INIT_CMD_LEN;
  76         spi_message_add_tail(&t, &m);
  77
  78         spi_sync(wl_to_spi(wl), &m);
  79
  80         wl1251_dump(DEBUG_SPI, "spi reset -> ", cmd, WSPI_INIT_CMD_LEN);
  81
  82         kfree(cmd);
  83 }
  84
  85 static void wl1251_spi_wake(struct wl1251 *wl)
  86 {
  87         struct spi_transfer t;
  88         struct spi_message m;
  89         u8 *cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
  90
  91         if (!cmd) {
  92                 wl1251_error("could not allocate cmd for spi init");
  93                 return;
  94         }
  95
  96         memset(&t, 0, sizeof(t));
  97         spi_message_init(&m);
  98
  99         /* Set WSPI_INIT_COMMAND
 100          * the data is being send from the MSB to LSB
 101          */
 102         cmd[0] = 0xff;
 103         cmd[1] = 0xff;
 104         cmd[2] = WSPI_INIT_CMD_START | WSPI_INIT_CMD_TX;
 105         cmd[3] = 0;
 106         cmd[4] = 0;
 107         cmd[5] = HW_ACCESS_WSPI_INIT_CMD_MASK << 3;
 108         cmd[5] |= HW_ACCESS_WSPI_FIXED_BUSY_LEN & WSPI_INIT_CMD_FIXEDBUSY_LEN;
 109
 110         cmd[6] = WSPI_INIT_CMD_IOD | WSPI_INIT_CMD_IP | WSPI_INIT_CMD_CS
 111                 | WSPI_INIT_CMD_WSPI | WSPI_INIT_CMD_WS;
 112
 113         if (HW_ACCESS_WSPI_FIXED_BUSY_LEN == 0)
 114                 cmd[6] |= WSPI_INIT_CMD_DIS_FIXEDBUSY;
 115         else
 116                 cmd[6] |= WSPI_INIT_CMD_EN_FIXEDBUSY;
 117
 118         cmd[7] = crc7_be(0, cmd+2, WSPI_INIT_CMD_CRC_LEN) | WSPI_INIT_CMD_END;
 119         /*
 120          * The above is the logical order; it must actually be stored
 121          * in the buffer byte-swapped.
 122          */
 123         __swab32s((u32 *)cmd);
 124         __swab32s((u32 *)cmd+1);
 125
 126         t.tx_buf = cmd;
 127         t.len = WSPI_INIT_CMD_LEN;
 128         spi_message_add_tail(&t, &m);
 129
 130         spi_sync(wl_to_spi(wl), &m);
 131
 132         wl1251_dump(DEBUG_SPI, "spi init -> ", cmd, WSPI_INIT_CMD_LEN);
 133
 134         kfree(cmd);
 135 }
 136
 137 static void wl1251_spi_reset_wake(struct wl1251 *wl)
 138 {
 139         wl1251_spi_reset(wl);
 140         wl1251_spi_wake(wl);
 141 }
 142
 143 static void wl1251_spi_read(struct wl1251 *wl, int addr, void *buf,
 144                             size_t len)
 145 {
 146         struct spi_transfer t[3];
 147         struct spi_message m;
 148         u8 *busy_buf;
 149         u32 *cmd;
 150
 151         cmd = &wl->buffer_cmd;
 152         busy_buf = wl->buffer_busyword;
 153
 154         *cmd = 0;
 155         *cmd |= WSPI_CMD_READ;
 156         *cmd |= (len << WSPI_CMD_BYTE_LENGTH_OFFSET) & WSPI_CMD_BYTE_LENGTH;
 157         *cmd |= addr & WSPI_CMD_BYTE_ADDR;
 158
 159         spi_message_init(&m);
 160         memset(t, 0, sizeof(t));
 161
 162         t[0].tx_buf = cmd;
 163         t[0].len = 4;
 164         spi_message_add_tail(&t[0], &m);
 165
 166         /* Busy and non busy words read */
 167         t[1].rx_buf = busy_buf;
 168         t[1].len = WL1251_BUSY_WORD_LEN;
 169         spi_message_add_tail(&t[1], &m);
 170
 171         t[2].rx_buf = buf;
 172         t[2].len = len;
 173         spi_message_add_tail(&t[2], &m);
 174
 175         spi_sync(wl_to_spi(wl), &m);
 176
 177         /* FIXME: check busy words */
 178
 179         wl1251_dump(DEBUG_SPI, "spi_read cmd -> ", cmd, sizeof(*cmd));
 180         wl1251_dump(DEBUG_SPI, "spi_read buf <- ", buf, len);
 181 }
 182
 183 static void wl1251_spi_write(struct wl1251 *wl, int addr, void *buf,
 184                              size_t len)
 185 {
 186         struct spi_transfer t[2];
 187         struct spi_message m;
 188         u32 *cmd;
 189
 190         cmd = &wl->buffer_cmd;
 191
 192         *cmd = 0;
 193         *cmd |= WSPI_CMD_WRITE;
 194         *cmd |= (len << WSPI_CMD_BYTE_LENGTH_OFFSET) & WSPI_CMD_BYTE_LENGTH;
 195         *cmd |= addr & WSPI_CMD_BYTE_ADDR;
 196
 197         spi_message_init(&m);
 198         memset(t, 0, sizeof(t));
 199
 200         t[0].tx_buf = cmd;
 201         t[0].len = sizeof(*cmd);
 202         spi_message_add_tail(&t[0], &m);
 203
 204         t[1].tx_buf = buf;
 205         t[1].len = len;
 206         spi_message_add_tail(&t[1], &m);
 207
 208         spi_sync(wl_to_spi(wl), &m);
 209
 210         wl1251_dump(DEBUG_SPI, "spi_write cmd -> ", cmd, sizeof(*cmd));
 211         wl1251_dump(DEBUG_SPI, "spi_write buf -> ", buf, len);
 212 }
 213
 214 static void wl1251_spi_enable_irq(struct wl1251 *wl)
 215 {
 216         return enable_irq(wl->irq);
 217 }
 218
 219 static void wl1251_spi_disable_irq(struct wl1251 *wl)
 220 {
 221         return disable_irq(wl->irq);
 222 }
 223
 224 static int wl1251_spi_set_power(struct wl1251 *wl, bool enable)
 225 {
 226         if (gpio_is_valid(wl->power_gpio))
 227                 gpio_set_value(wl->power_gpio, enable);
 228
 229         return 0;
 230 }
 231
 232 static const struct wl1251_if_operations wl1251_spi_ops = {
 233         .read = wl1251_spi_read,
 234         .write = wl1251_spi_write,
 235         .reset = wl1251_spi_reset_wake,
 236         .enable_irq = wl1251_spi_enable_irq,
 237         .disable_irq = wl1251_spi_disable_irq,
 238         .power = wl1251_spi_set_power,
 239 };
 240
 241 static int wl1251_spi_probe(struct spi_device *spi)
 242 {
 243         struct wl1251_platform_data *pdata = dev_get_platdata(&spi->dev);
 244         struct device_node *np = spi->dev.of_node;
 245         struct ieee80211_hw *hw;
 246         struct wl1251 *wl;
 247         int ret;
 248
 249         if (!np && !pdata) {
 250                 wl1251_error("no platform data");
 251                 return -ENODEV;
 252         }
 253
 254         hw = wl1251_alloc_hw();
 255         if (IS_ERR(hw))
 256                 return PTR_ERR(hw);
 257
 258         wl = hw->priv;
 259
 260         SET_IEEE80211_DEV(hw, &spi->dev);
 261         spi_set_drvdata(spi, wl);
 262         wl->if_priv = spi;
 263         wl->if_ops = &wl1251_spi_ops;
 264
 265         /* This is the only SPI value that we need to set here, the rest
 266          * comes from the board-peripherals file
 267          */
 268         spi->bits_per_word = 32;
 269
 270         ret = spi_setup(spi);
 271         if (ret < 0) {
 272                 wl1251_error("spi_setup failed");
 273                 goto out_free;
 274         }
 275
 276         if (np) {
 277                 wl->use_eeprom = of_property_read_bool(np, "ti,wl1251-has-eeprom");
 278                 wl->power_gpio = of_get_named_gpio(np, "ti,power-gpio", 0);
 279         } else if (pdata) {
 280                 wl->power_gpio = pdata->power_gpio;
 281                 wl->use_eeprom = pdata->use_eeprom;
 282         }
 283
 284         if (wl->power_gpio == -EPROBE_DEFER) {
 285                 ret = -EPROBE_DEFER;
 286                 goto out_free;
 287         }
 288
 289         if (gpio_is_valid(wl->power_gpio)) {
 290                 ret = devm_gpio_request_one(&spi->dev, wl->power_gpio,
 291                                         GPIOF_OUT_INIT_LOW, "wl1251 power");
 292                 if (ret) {
 293                         wl1251_error("Failed to request gpio: %d\n", ret);
 294                         goto out_free;
 295                 }
 296         } else {
 297                 wl1251_error("set power gpio missing in platform data");
 298                 ret = -ENODEV;
 299                 goto out_free;
 300         }
 301
 302         wl->irq = spi->irq;
 303         if (wl->irq < 0) {
 304                 wl1251_error("irq missing in platform data");
 305                 ret = -ENODEV;
 306                 goto out_free;
 307         }
 308
 309         irq_set_status_flags(wl->irq, IRQ_NOAUTOEN);
 310         ret = devm_request_irq(&spi->dev, wl->irq, wl1251_irq, 0,
 311                                                         DRIVER_NAME, wl);
 312         if (ret < 0) {
 313                 wl1251_error("request_irq() failed: %d", ret);
 314                 goto out_free;
 315         }
 316
 317         irq_set_irq_type(wl->irq, IRQ_TYPE_EDGE_RISING);
 318
 319         wl->vio = devm_regulator_get(&spi->dev, "vio");
 320         if (IS_ERR(wl->vio)) {
 321                 ret = PTR_ERR(wl->vio);
 322                 wl1251_error("vio regulator missing: %d", ret);
 323                 goto out_free;
 324         }
 325
 326         ret = regulator_enable(wl->vio);
 327         if (ret)
 328                 goto out_free;
 329
 330         ret = wl1251_init_ieee80211(wl);
 331         if (ret)
 332                 goto disable_regulator;
 333
 334         return 0;
 335
 336 disable_regulator:
 337         regulator_disable(wl->vio);
 338 out_free:
 339         ieee80211_free_hw(hw);
 340
 341         return ret;
 342 }
 343
 344 static int wl1251_spi_remove(struct spi_device *spi)
 345 {
 346         struct wl1251 *wl = spi_get_drvdata(spi);
 347
 348         wl1251_free_hw(wl);
 349         regulator_disable(wl->vio);
 350
 351         return 0;
 352 }
 353
 354 static struct spi_driver wl1251_spi_driver = {
 355         .driver = {
 356                 .name           = DRIVER_NAME,
 357                 .owner          = THIS_MODULE,
 358         },
 359
 360         .probe          = wl1251_spi_probe,
 361         .remove         = wl1251_spi_remove,
 362 };
 363
 364 module_spi_driver(wl1251_spi_driver);
 365
 366 MODULE_LICENSE("GPL");
 367 MODULE_AUTHOR("Kalle Valo <kvalo@adurom.com>");
 368 MODULE_ALIAS("spi:wl1251");