drivers/net/ieee802154/cc2520.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /* Driver for TI CC2520 802.15.4 Wireless-PAN Networking controller
   3  *
   4  * Copyright (C) 2014 Varka Bhadram <varkab@cdac.in>
   5  *                    Md.Jamal Mohiuddin <mjmohiuddin@cdac.in>
   6  *                    P Sowjanya <sowjanyap@cdac.in>
   7  */
   8 #include <linux/kernel.h>
   9 #include <linux/module.h>
  10 #include <linux/gpio/consumer.h>
  11 #include <linux/delay.h>
  12 #include <linux/spi/spi.h>
  13 #include <linux/property.h>
  14 #include <linux/workqueue.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/skbuff.h>
  17 #include <linux/ieee802154.h>
  18 #include <linux/crc-ccitt.h>
  19 #include <asm/unaligned.h>
  20
  21 #include <net/mac802154.h>
  22 #include <net/cfg802154.h>
  23
  24 #define SPI_COMMAND_BUFFER      3
  25 #define HIGH                    1
  26 #define LOW                     0
  27 #define STATE_IDLE              0
  28 #define RSSI_VALID              0
  29 #define RSSI_OFFSET             78
  30
  31 #define CC2520_RAM_SIZE         640
  32 #define CC2520_FIFO_SIZE        128
  33
  34 #define CC2520RAM_TXFIFO        0x100
  35 #define CC2520RAM_RXFIFO        0x180
  36 #define CC2520RAM_IEEEADDR      0x3EA
  37 #define CC2520RAM_PANID         0x3F2
  38 #define CC2520RAM_SHORTADDR     0x3F4
  39
  40 #define CC2520_FREG_MASK        0x3F
  41
  42 /* status byte values */
  43 #define CC2520_STATUS_XOSC32M_STABLE    BIT(7)
  44 #define CC2520_STATUS_RSSI_VALID        BIT(6)
  45 #define CC2520_STATUS_TX_UNDERFLOW      BIT(3)
  46
  47 /* IEEE-802.15.4 defined constants (2.4 GHz logical channels) */
  48 #define CC2520_MINCHANNEL               11
  49 #define CC2520_MAXCHANNEL               26
  50 #define CC2520_CHANNEL_SPACING          5
  51
  52 /* command strobes */
  53 #define CC2520_CMD_SNOP                 0x00
  54 #define CC2520_CMD_IBUFLD               0x02
  55 #define CC2520_CMD_SIBUFEX              0x03
  56 #define CC2520_CMD_SSAMPLECCA           0x04
  57 #define CC2520_CMD_SRES                 0x0f
  58 #define CC2520_CMD_MEMORY_MASK          0x0f
  59 #define CC2520_CMD_MEMORY_READ          0x10
  60 #define CC2520_CMD_MEMORY_WRITE         0x20
  61 #define CC2520_CMD_RXBUF                0x30
  62 #define CC2520_CMD_RXBUFCP              0x38
  63 #define CC2520_CMD_RXBUFMOV             0x32
  64 #define CC2520_CMD_TXBUF                0x3A
  65 #define CC2520_CMD_TXBUFCP              0x3E
  66 #define CC2520_CMD_RANDOM               0x3C
  67 #define CC2520_CMD_SXOSCON              0x40
  68 #define CC2520_CMD_STXCAL               0x41
  69 #define CC2520_CMD_SRXON                0x42
  70 #define CC2520_CMD_STXON                0x43
  71 #define CC2520_CMD_STXONCCA             0x44
  72 #define CC2520_CMD_SRFOFF               0x45
  73 #define CC2520_CMD_SXOSCOFF             0x46
  74 #define CC2520_CMD_SFLUSHRX             0x47
  75 #define CC2520_CMD_SFLUSHTX             0x48
  76 #define CC2520_CMD_SACK                 0x49
  77 #define CC2520_CMD_SACKPEND             0x4A
  78 #define CC2520_CMD_SNACK                0x4B
  79 #define CC2520_CMD_SRXMASKBITSET        0x4C
  80 #define CC2520_CMD_SRXMASKBITCLR        0x4D
  81 #define CC2520_CMD_RXMASKAND            0x4E
  82 #define CC2520_CMD_RXMASKOR             0x4F
  83 #define CC2520_CMD_MEMCP                0x50
  84 #define CC2520_CMD_MEMCPR               0x52
  85 #define CC2520_CMD_MEMXCP               0x54
  86 #define CC2520_CMD_MEMXWR               0x56
  87 #define CC2520_CMD_BCLR                 0x58
  88 #define CC2520_CMD_BSET                 0x59
  89 #define CC2520_CMD_CTR_UCTR             0x60
  90 #define CC2520_CMD_CBCMAC               0x64
  91 #define CC2520_CMD_UCBCMAC              0x66
  92 #define CC2520_CMD_CCM                  0x68
  93 #define CC2520_CMD_UCCM                 0x6A
  94 #define CC2520_CMD_ECB                  0x70
  95 #define CC2520_CMD_ECBO                 0x72
  96 #define CC2520_CMD_ECBX                 0x74
  97 #define CC2520_CMD_INC                  0x78
  98 #define CC2520_CMD_ABORT                0x7F
  99 #define CC2520_CMD_REGISTER_READ        0x80
 100 #define CC2520_CMD_REGISTER_WRITE       0xC0
 101
 102 /* status registers */
 103 #define CC2520_CHIPID                   0x40
 104 #define CC2520_VERSION                  0x42
 105 #define CC2520_EXTCLOCK                 0x44
 106 #define CC2520_MDMCTRL0                 0x46
 107 #define CC2520_MDMCTRL1                 0x47
 108 #define CC2520_FREQEST                  0x48
 109 #define CC2520_RXCTRL                   0x4A
 110 #define CC2520_FSCTRL                   0x4C
 111 #define CC2520_FSCAL0                   0x4E
 112 #define CC2520_FSCAL1                   0x4F
 113 #define CC2520_FSCAL2                   0x50
 114 #define CC2520_FSCAL3                   0x51
 115 #define CC2520_AGCCTRL0                 0x52
 116 #define CC2520_AGCCTRL1                 0x53
 117 #define CC2520_AGCCTRL2                 0x54
 118 #define CC2520_AGCCTRL3                 0x55
 119 #define CC2520_ADCTEST0                 0x56
 120 #define CC2520_ADCTEST1                 0x57
 121 #define CC2520_ADCTEST2                 0x58
 122 #define CC2520_MDMTEST0                 0x5A
 123 #define CC2520_MDMTEST1                 0x5B
 124 #define CC2520_DACTEST0                 0x5C
 125 #define CC2520_DACTEST1                 0x5D
 126 #define CC2520_ATEST                    0x5E
 127 #define CC2520_DACTEST2                 0x5F
 128 #define CC2520_PTEST0                   0x60
 129 #define CC2520_PTEST1                   0x61
 130 #define CC2520_RESERVED                 0x62
 131 #define CC2520_DPUBIST                  0x7A
 132 #define CC2520_ACTBIST                  0x7C
 133 #define CC2520_RAMBIST                  0x7E
 134
 135 /* frame registers */
 136 #define CC2520_FRMFILT0                 0x00
 137 #define CC2520_FRMFILT1                 0x01
 138 #define CC2520_SRCMATCH                 0x02
 139 #define CC2520_SRCSHORTEN0              0x04
 140 #define CC2520_SRCSHORTEN1              0x05
 141 #define CC2520_SRCSHORTEN2              0x06
 142 #define CC2520_SRCEXTEN0                0x08
 143 #define CC2520_SRCEXTEN1                0x09
 144 #define CC2520_SRCEXTEN2                0x0A
 145 #define CC2520_FRMCTRL0                 0x0C
 146 #define CC2520_FRMCTRL1                 0x0D
 147 #define CC2520_RXENABLE0                0x0E
 148 #define CC2520_RXENABLE1                0x0F
 149 #define CC2520_EXCFLAG0                 0x10
 150 #define CC2520_EXCFLAG1                 0x11
 151 #define CC2520_EXCFLAG2                 0x12
 152 #define CC2520_EXCMASKA0                0x14
 153 #define CC2520_EXCMASKA1                0x15
 154 #define CC2520_EXCMASKA2                0x16
 155 #define CC2520_EXCMASKB0                0x18
 156 #define CC2520_EXCMASKB1                0x19
 157 #define CC2520_EXCMASKB2                0x1A
 158 #define CC2520_EXCBINDX0                0x1C
 159 #define CC2520_EXCBINDX1                0x1D
 160 #define CC2520_EXCBINDY0                0x1E
 161 #define CC2520_EXCBINDY1                0x1F
 162 #define CC2520_GPIOCTRL0                0x20
 163 #define CC2520_GPIOCTRL1                0x21
 164 #define CC2520_GPIOCTRL2                0x22
 165 #define CC2520_GPIOCTRL3                0x23
 166 #define CC2520_GPIOCTRL4                0x24
 167 #define CC2520_GPIOCTRL5                0x25
 168 #define CC2520_GPIOPOLARITY             0x26
 169 #define CC2520_GPIOCTRL                 0x28
 170 #define CC2520_DPUCON                   0x2A
 171 #define CC2520_DPUSTAT                  0x2C
 172 #define CC2520_FREQCTRL                 0x2E
 173 #define CC2520_FREQTUNE                 0x2F
 174 #define CC2520_TXPOWER                  0x30
 175 #define CC2520_TXCTRL                   0x31
 176 #define CC2520_FSMSTAT0                 0x32
 177 #define CC2520_FSMSTAT1                 0x33
 178 #define CC2520_FIFOPCTRL                0x34
 179 #define CC2520_FSMCTRL                  0x35
 180 #define CC2520_CCACTRL0                 0x36
 181 #define CC2520_CCACTRL1                 0x37
 182 #define CC2520_RSSI                     0x38
 183 #define CC2520_RSSISTAT                 0x39
 184 #define CC2520_RXFIRST                  0x3C
 185 #define CC2520_RXFIFOCNT                0x3E
 186 #define CC2520_TXFIFOCNT                0x3F
 187
 188 /* CC2520_FRMFILT0 */
 189 #define FRMFILT0_FRAME_FILTER_EN        BIT(0)
 190 #define FRMFILT0_PAN_COORDINATOR        BIT(1)
 191
 192 /* CC2520_FRMCTRL0 */
 193 #define FRMCTRL0_AUTOACK                BIT(5)
 194 #define FRMCTRL0_AUTOCRC                BIT(6)
 195
 196 /* CC2520_FRMCTRL1 */
 197 #define FRMCTRL1_SET_RXENMASK_ON_TX     BIT(0)
 198 #define FRMCTRL1_IGNORE_TX_UNDERF       BIT(1)
 199
 200 /* Driver private information */
 201 struct cc2520_private {
 202         struct spi_device *spi;         /* SPI device structure */
 203         struct ieee802154_hw *hw;       /* IEEE-802.15.4 device */
 204         u8 *buf;                        /* SPI TX/Rx data buffer */
 205         struct mutex buffer_mutex;      /* SPI buffer mutex */
 206         bool is_tx;                     /* Flag for sync b/w Tx and Rx */
 207         bool amplified;                 /* Flag for CC2591 */
 208         struct gpio_desc *fifo_pin;     /* FIFO GPIO pin number */
 209         struct work_struct fifop_irqwork;/* Workqueue for FIFOP */
 210         spinlock_t lock;                /* Lock for is_tx*/
 211         struct completion tx_complete;  /* Work completion for Tx */
 212         bool promiscuous;               /* Flag for promiscuous mode */
 213 };
 214
 215 /* Generic Functions */
 216 static int
 217 cc2520_cmd_strobe(struct cc2520_private *priv, u8 cmd)
 218 {
 219         int ret;
 220         struct spi_message msg;
 221         struct spi_transfer xfer = {
 222                 .len = 0,
 223                 .tx_buf = priv->buf,
 224                 .rx_buf = priv->buf,
 225         };
 226
 227         spi_message_init(&msg);
 228         spi_message_add_tail(&xfer, &msg);
 229
 230         mutex_lock(&priv->buffer_mutex);
 231         priv->buf[xfer.len++] = cmd;
 232         dev_vdbg(&priv->spi->dev,
 233                  "command strobe buf[0] = %02x\n",
 234                  priv->buf[0]);
 235
 236         ret = spi_sync(priv->spi, &msg);
 237         dev_vdbg(&priv->spi->dev,
 238                  "buf[0] = %02x\n", priv->buf[0]);
 239         mutex_unlock(&priv->buffer_mutex);
 240
 241         return ret;
 242 }
 243
 244 static int
 245 cc2520_get_status(struct cc2520_private *priv, u8 *status)
 246 {
 247         int ret;
 248         struct spi_message msg;
 249         struct spi_transfer xfer = {
 250                 .len = 0,
 251                 .tx_buf = priv->buf,
 252                 .rx_buf = priv->buf,
 253         };
 254
 255         spi_message_init(&msg);
 256         spi_message_add_tail(&xfer, &msg);
 257
 258         mutex_lock(&priv->buffer_mutex);
 259         priv->buf[xfer.len++] = CC2520_CMD_SNOP;
 260         dev_vdbg(&priv->spi->dev,
 261                  "get status command buf[0] = %02x\n", priv->buf[0]);
 262
 263         ret = spi_sync(priv->spi, &msg);
 264         if (!ret)
 265                 *status = priv->buf[0];
 266         dev_vdbg(&priv->spi->dev,
 267                  "buf[0] = %02x\n", priv->buf[0]);
 268         mutex_unlock(&priv->buffer_mutex);
 269
 270         return ret;
 271 }
 272
 273 static int
 274 cc2520_write_register(struct cc2520_private *priv, u8 reg, u8 value)
 275 {
 276         int status;
 277         struct spi_message msg;
 278         struct spi_transfer xfer = {
 279                 .len = 0,
 280                 .tx_buf = priv->buf,
 281                 .rx_buf = priv->buf,
 282         };
 283
 284         spi_message_init(&msg);
 285         spi_message_add_tail(&xfer, &msg);
 286
 287         mutex_lock(&priv->buffer_mutex);
 288
 289         if (reg <= CC2520_FREG_MASK) {
 290                 priv->buf[xfer.len++] = CC2520_CMD_REGISTER_WRITE | reg;
 291                 priv->buf[xfer.len++] = value;
 292         } else {
 293                 priv->buf[xfer.len++] = CC2520_CMD_MEMORY_WRITE;
 294                 priv->buf[xfer.len++] = reg;
 295                 priv->buf[xfer.len++] = value;
 296         }
 297         status = spi_sync(priv->spi, &msg);
 298         if (msg.status)
 299                 status = msg.status;
 300
 301         mutex_unlock(&priv->buffer_mutex);
 302
 303         return status;
 304 }
 305
 306 static int
 307 cc2520_write_ram(struct cc2520_private *priv, u16 reg, u8 len, u8 *data)
 308 {
 309         int status;
 310         struct spi_message msg;
 311         struct spi_transfer xfer_head = {
 312                 .len        = 0,
 313                 .tx_buf        = priv->buf,
 314                 .rx_buf        = priv->buf,
 315         };
 316
 317         struct spi_transfer xfer_buf = {
 318                 .len = len,
 319                 .tx_buf = data,
 320         };
 321
 322         mutex_lock(&priv->buffer_mutex);
 323         priv->buf[xfer_head.len++] = (CC2520_CMD_MEMORY_WRITE |
 324                                                 ((reg >> 8) & 0xff));
 325         priv->buf[xfer_head.len++] = reg & 0xff;
 326
 327         spi_message_init(&msg);
 328         spi_message_add_tail(&xfer_head, &msg);
 329         spi_message_add_tail(&xfer_buf, &msg);
 330
 331         status = spi_sync(priv->spi, &msg);
 332         dev_dbg(&priv->spi->dev, "spi status = %d\n", status);
 333         if (msg.status)
 334                 status = msg.status;
 335
 336         mutex_unlock(&priv->buffer_mutex);
 337         return status;
 338 }
 339
 340 static int
 341 cc2520_read_register(struct cc2520_private *priv, u8 reg, u8 *data)
 342 {
 343         int status;
 344         struct spi_message msg;
 345         struct spi_transfer xfer1 = {
 346                 .len = 0,
 347                 .tx_buf = priv->buf,
 348                 .rx_buf = priv->buf,
 349         };
 350
 351         struct spi_transfer xfer2 = {
 352                 .len = 1,
 353                 .rx_buf = data,
 354         };
 355
 356         spi_message_init(&msg);
 357         spi_message_add_tail(&xfer1, &msg);
 358         spi_message_add_tail(&xfer2, &msg);
 359
 360         mutex_lock(&priv->buffer_mutex);
 361         priv->buf[xfer1.len++] = CC2520_CMD_MEMORY_READ;
 362         priv->buf[xfer1.len++] = reg;
 363
 364         status = spi_sync(priv->spi, &msg);
 365         dev_dbg(&priv->spi->dev,
 366                 "spi status = %d\n", status);
 367         if (msg.status)
 368                 status = msg.status;
 369
 370         mutex_unlock(&priv->buffer_mutex);
 371
 372         return status;
 373 }
 374
 375 static int
 376 cc2520_write_txfifo(struct cc2520_private *priv, u8 pkt_len, u8 *data, u8 len)
 377 {
 378         int status;
 379
 380         /* length byte must include FCS even
 381          * if it is calculated in the hardware
 382          */
 383         int len_byte = pkt_len;
 384
 385         struct spi_message msg;
 386
 387         struct spi_transfer xfer_head = {
 388                 .len = 0,
 389                 .tx_buf = priv->buf,
 390                 .rx_buf = priv->buf,
 391         };
 392         struct spi_transfer xfer_len = {
 393                 .len = 1,
 394                 .tx_buf = &len_byte,
 395         };
 396         struct spi_transfer xfer_buf = {
 397                 .len = len,
 398                 .tx_buf = data,
 399         };
 400
 401         spi_message_init(&msg);
 402         spi_message_add_tail(&xfer_head, &msg);
 403         spi_message_add_tail(&xfer_len, &msg);
 404         spi_message_add_tail(&xfer_buf, &msg);
 405
 406         mutex_lock(&priv->buffer_mutex);
 407         priv->buf[xfer_head.len++] = CC2520_CMD_TXBUF;
 408         dev_vdbg(&priv->spi->dev,
 409                  "TX_FIFO cmd buf[0] = %02x\n", priv->buf[0]);
 410
 411         status = spi_sync(priv->spi, &msg);
 412         dev_vdbg(&priv->spi->dev, "status = %d\n", status);
 413         if (msg.status)
 414                 status = msg.status;
 415         dev_vdbg(&priv->spi->dev, "status = %d\n", status);
 416         dev_vdbg(&priv->spi->dev, "buf[0] = %02x\n", priv->buf[0]);
 417         mutex_unlock(&priv->buffer_mutex);
 418
 419         return status;
 420 }
 421
 422 static int
 423 cc2520_read_rxfifo(struct cc2520_private *priv, u8 *data, u8 len)
 424 {
 425         int status;
 426         struct spi_message msg;
 427
 428         struct spi_transfer xfer_head = {
 429                 .len = 0,
 430                 .tx_buf = priv->buf,
 431                 .rx_buf = priv->buf,
 432         };
 433         struct spi_transfer xfer_buf = {
 434                 .len = len,
 435                 .rx_buf = data,
 436         };
 437
 438         spi_message_init(&msg);
 439         spi_message_add_tail(&xfer_head, &msg);
 440         spi_message_add_tail(&xfer_buf, &msg);
 441
 442         mutex_lock(&priv->buffer_mutex);
 443         priv->buf[xfer_head.len++] = CC2520_CMD_RXBUF;
 444
 445         dev_vdbg(&priv->spi->dev, "read rxfifo buf[0] = %02x\n", priv->buf[0]);
 446         dev_vdbg(&priv->spi->dev, "buf[1] = %02x\n", priv->buf[1]);
 447
 448         status = spi_sync(priv->spi, &msg);
 449         dev_vdbg(&priv->spi->dev, "status = %d\n", status);
 450         if (msg.status)
 451                 status = msg.status;
 452         dev_vdbg(&priv->spi->dev, "status = %d\n", status);
 453         dev_vdbg(&priv->spi->dev,
 454                  "return status buf[0] = %02x\n", priv->buf[0]);
 455         dev_vdbg(&priv->spi->dev, "length buf[1] = %02x\n", priv->buf[1]);
 456
 457         mutex_unlock(&priv->buffer_mutex);
 458
 459         return status;
 460 }
 461
 462 static int cc2520_start(struct ieee802154_hw *hw)
 463 {
 464         return cc2520_cmd_strobe(hw->priv, CC2520_CMD_SRXON);
 465 }
 466
 467 static void cc2520_stop(struct ieee802154_hw *hw)
 468 {
 469         cc2520_cmd_strobe(hw->priv, CC2520_CMD_SRFOFF);
 470 }
 471
 472 static int
 473 cc2520_tx(struct ieee802154_hw *hw, struct sk_buff *skb)
 474 {
 475         struct cc2520_private *priv = hw->priv;
 476         unsigned long flags;
 477         int rc;
 478         u8 status = 0;
 479         u8 pkt_len;
 480
 481         /* In promiscuous mode we disable AUTOCRC so we can get the raw CRC
 482          * values on RX. This means we need to manually add the CRC on TX.
 483          */
 484         if (priv->promiscuous) {
 485                 u16 crc = crc_ccitt(0, skb->data, skb->len);
 486
 487                 put_unaligned_le16(crc, skb_put(skb, 2));
 488                 pkt_len = skb->len;
 489         } else {
 490                 pkt_len = skb->len + 2;
 491         }
 492
 493         rc = cc2520_cmd_strobe(priv, CC2520_CMD_SFLUSHTX);
 494         if (rc)
 495                 goto err_tx;
 496
 497         rc = cc2520_write_txfifo(priv, pkt_len, skb->data, skb->len);
 498         if (rc)
 499                 goto err_tx;
 500
 501         rc = cc2520_get_status(priv, &status);
 502         if (rc)
 503                 goto err_tx;
 504
 505         if (status & CC2520_STATUS_TX_UNDERFLOW) {
 506                 rc = -EINVAL;
 507                 dev_err(&priv->spi->dev, "cc2520 tx underflow exception\n");
 508                 goto err_tx;
 509         }
 510
 511         spin_lock_irqsave(&priv->lock, flags);
 512         WARN_ON(priv->is_tx);
 513         priv->is_tx = 1;
 514         spin_unlock_irqrestore(&priv->lock, flags);
 515
 516         rc = cc2520_cmd_strobe(priv, CC2520_CMD_STXONCCA);
 517         if (rc)
 518                 goto err;
 519
 520         rc = wait_for_completion_interruptible(&priv->tx_complete);
 521         if (rc < 0)
 522                 goto err;
 523
 524         cc2520_cmd_strobe(priv, CC2520_CMD_SFLUSHTX);
 525         cc2520_cmd_strobe(priv, CC2520_CMD_SRXON);
 526
 527         return rc;
 528 err:
 529         spin_lock_irqsave(&priv->lock, flags);
 530         priv->is_tx = 0;
 531         spin_unlock_irqrestore(&priv->lock, flags);
 532 err_tx:
 533         return rc;
 534 }
 535
 536 static int cc2520_rx(struct cc2520_private *priv)
 537 {
 538         u8 len = 0, lqi = 0, bytes = 1;
 539         struct sk_buff *skb;
 540
 541         /* Read single length byte from the radio. */
 542         cc2520_read_rxfifo(priv, &len, bytes);
 543
 544         if (!ieee802154_is_valid_psdu_len(len)) {
 545                 /* Corrupted frame received, clear frame buffer by
 546                  * reading entire buffer.
 547                  */
 548                 dev_dbg(&priv->spi->dev, "corrupted frame received\n");
 549                 len = IEEE802154_MTU;
 550         }
 551
 552         skb = dev_alloc_skb(len);
 553         if (!skb)
 554                 return -ENOMEM;
 555
 556         if (cc2520_read_rxfifo(priv, skb_put(skb, len), len)) {
 557                 dev_dbg(&priv->spi->dev, "frame reception failed\n");
 558                 kfree_skb(skb);
 559                 return -EINVAL;
 560         }
 561
 562         /* In promiscuous mode, we configure the radio to include the
 563          * CRC (AUTOCRC==0) and we pass on the packet unconditionally. If not
 564          * in promiscuous mode, we check the CRC here, but leave the
 565          * RSSI/LQI/CRC_OK bytes as they will get removed in the mac layer.
 566          */
 567         if (!priv->promiscuous) {
 568                 bool crc_ok;
 569
 570                 /* Check if the CRC is valid. With AUTOCRC set, the most
 571                  * significant bit of the last byte returned from the CC2520
 572                  * is CRC_OK flag. See section 20.3.4 of the datasheet.
 573                  */
 574                 crc_ok = skb->data[len - 1] & BIT(7);
 575
 576                 /* If we failed CRC drop the packet in the driver layer. */
 577                 if (!crc_ok) {
 578                         dev_dbg(&priv->spi->dev, "CRC check failed\n");
 579                         kfree_skb(skb);
 580                         return -EINVAL;
 581                 }
 582
 583                 /* To calculate LQI, the lower 7 bits of the last byte (the
 584                  * correlation value provided by the radio) must be scaled to
 585                  * the range 0-255. According to section 20.6, the correlation
 586                  * value ranges from 50-110. Ideally this would be calibrated
 587                  * per hardware design, but we use roughly the datasheet values
 588                  * to get close enough while avoiding floating point.
 589                  */
 590                 lqi = skb->data[len - 1] & 0x7f;
 591                 if (lqi < 50)
 592                         lqi = 50;
 593                 else if (lqi > 113)
 594                         lqi = 113;
 595                 lqi = (lqi - 50) * 4;
 596         }
 597
 598         ieee802154_rx_irqsafe(priv->hw, skb, lqi);
 599
 600         dev_vdbg(&priv->spi->dev, "RXFIFO: %x %x\n", len, lqi);
 601
 602         return 0;
 603 }
 604
 605 static int
 606 cc2520_ed(struct ieee802154_hw *hw, u8 *level)
 607 {
 608         struct cc2520_private *priv = hw->priv;
 609         u8 status = 0xff;
 610         u8 rssi;
 611         int ret;
 612
 613         ret = cc2520_read_register(priv, CC2520_RSSISTAT, &status);
 614         if (ret)
 615                 return ret;
 616
 617         if (status != RSSI_VALID)
 618                 return -EINVAL;
 619
 620         ret = cc2520_read_register(priv, CC2520_RSSI, &rssi);
 621         if (ret)
 622                 return ret;
 623
 624         /* level = RSSI(rssi) - OFFSET [dBm] : offset is 76dBm */
 625         *level = rssi - RSSI_OFFSET;
 626
 627         return 0;
 628 }
 629
 630 static int
 631 cc2520_set_channel(struct ieee802154_hw *hw, u8 page, u8 channel)
 632 {
 633         struct cc2520_private *priv = hw->priv;
 634         int ret;
 635
 636         dev_dbg(&priv->spi->dev, "trying to set channel\n");
 637
 638         WARN_ON(page != 0);
 639         WARN_ON(channel < CC2520_MINCHANNEL);
 640         WARN_ON(channel > CC2520_MAXCHANNEL);
 641
 642         ret = cc2520_write_register(priv, CC2520_FREQCTRL,
 643                                     11 + 5 * (channel - 11));
 644
 645         return ret;
 646 }
 647
 648 static int
 649 cc2520_filter(struct ieee802154_hw *hw,
 650               struct ieee802154_hw_addr_filt *filt, unsigned long changed)
 651 {
 652         struct cc2520_private *priv = hw->priv;
 653         int ret = 0;
 654
 655         if (changed & IEEE802154_AFILT_PANID_CHANGED) {
 656                 u16 panid = le16_to_cpu(filt->pan_id);
 657
 658                 dev_vdbg(&priv->spi->dev, "%s called for pan id\n", __func__);
 659                 ret = cc2520_write_ram(priv, CC2520RAM_PANID,
 660                                        sizeof(panid), (u8 *)&panid);
 661         }
 662
 663         if (changed & IEEE802154_AFILT_IEEEADDR_CHANGED) {
 664                 dev_vdbg(&priv->spi->dev,
 665                          "%s called for IEEE addr\n", __func__);
 666                 ret = cc2520_write_ram(priv, CC2520RAM_IEEEADDR,
 667                                        sizeof(filt->ieee_addr),
 668                                        (u8 *)&filt->ieee_addr);
 669         }
 670
 671         if (changed & IEEE802154_AFILT_SADDR_CHANGED) {
 672                 u16 addr = le16_to_cpu(filt->short_addr);
 673
 674                 dev_vdbg(&priv->spi->dev, "%s called for saddr\n", __func__);
 675                 ret = cc2520_write_ram(priv, CC2520RAM_SHORTADDR,
 676                                        sizeof(addr), (u8 *)&addr);
 677         }
 678
 679         if (changed & IEEE802154_AFILT_PANC_CHANGED) {
 680                 u8 frmfilt0;
 681
 682                 dev_vdbg(&priv->spi->dev,
 683                          "%s called for panc change\n", __func__);
 684
 685                 cc2520_read_register(priv, CC2520_FRMFILT0, &frmfilt0);
 686
 687                 if (filt->pan_coord)
 688                         frmfilt0 |= FRMFILT0_PAN_COORDINATOR;
 689                 else
 690                         frmfilt0 &= ~FRMFILT0_PAN_COORDINATOR;
 691
 692                 ret = cc2520_write_register(priv, CC2520_FRMFILT0, frmfilt0);
 693         }
 694
 695         return ret;
 696 }
 697
 698 static inline int cc2520_set_tx_power(struct cc2520_private *priv, s32 mbm)
 699 {
 700         u8 power;
 701
 702         switch (mbm) {
 703         case 500:
 704                 power = 0xF7;
 705                 break;
 706         case 300:
 707                 power = 0xF2;
 708                 break;
 709         case 200:
 710                 power = 0xAB;
 711                 break;
 712         case 100:
 713                 power = 0x13;
 714                 break;
 715         case 0:
 716                 power = 0x32;
 717                 break;
 718         case -200:
 719                 power = 0x81;
 720                 break;
 721         case -400:
 722                 power = 0x88;
 723                 break;
 724         case -700:
 725                 power = 0x2C;
 726                 break;
 727         case -1800:
 728                 power = 0x03;
 729                 break;
 730         default:
 731                 return -EINVAL;
 732         }
 733
 734         return cc2520_write_register(priv, CC2520_TXPOWER, power);
 735 }
 736
 737 static inline int cc2520_cc2591_set_tx_power(struct cc2520_private *priv,
 738                                              s32 mbm)
 739 {
 740         u8 power;
 741
 742         switch (mbm) {
 743         case 1700:
 744                 power = 0xF9;
 745                 break;
 746         case 1600:
 747                 power = 0xF0;
 748                 break;
 749         case 1400:
 750                 power = 0xA0;
 751                 break;
 752         case 1100:
 753                 power = 0x2C;
 754                 break;
 755         case -100:
 756                 power = 0x03;
 757                 break;
 758         case -800:
 759                 power = 0x01;
 760                 break;
 761         default:
 762                 return -EINVAL;
 763         }
 764
 765         return cc2520_write_register(priv, CC2520_TXPOWER, power);
 766 }
 767
 768 #define CC2520_MAX_TX_POWERS 0x8
 769 static const s32 cc2520_powers[CC2520_MAX_TX_POWERS + 1] = {
 770         500, 300, 200, 100, 0, -200, -400, -700, -1800,
 771 };
 772
 773 #define CC2520_CC2591_MAX_TX_POWERS 0x5
 774 static const s32 cc2520_cc2591_powers[CC2520_CC2591_MAX_TX_POWERS + 1] = {
 775         1700, 1600, 1400, 1100, -100, -800,
 776 };
 777
 778 static int
 779 cc2520_set_txpower(struct ieee802154_hw *hw, s32 mbm)
 780 {
 781         struct cc2520_private *priv = hw->priv;
 782
 783         if (!priv->amplified)
 784                 return cc2520_set_tx_power(priv, mbm);
 785
 786         return cc2520_cc2591_set_tx_power(priv, mbm);
 787 }
 788
 789 static int
 790 cc2520_set_promiscuous_mode(struct ieee802154_hw *hw, bool on)
 791 {
 792         struct cc2520_private *priv = hw->priv;
 793         u8 frmfilt0;
 794
 795         dev_dbg(&priv->spi->dev, "%s : mode %d\n", __func__, on);
 796
 797         priv->promiscuous = on;
 798
 799         cc2520_read_register(priv, CC2520_FRMFILT0, &frmfilt0);
 800
 801         if (on) {
 802                 /* Disable automatic ACK, automatic CRC, and frame filtering. */
 803                 cc2520_write_register(priv, CC2520_FRMCTRL0, 0);
 804                 frmfilt0 &= ~FRMFILT0_FRAME_FILTER_EN;
 805         } else {
 806                 cc2520_write_register(priv, CC2520_FRMCTRL0, FRMCTRL0_AUTOACK |
 807                                                              FRMCTRL0_AUTOCRC);
 808                 frmfilt0 |= FRMFILT0_FRAME_FILTER_EN;
 809         }
 810         return cc2520_write_register(priv, CC2520_FRMFILT0, frmfilt0);
 811 }
 812
 813 static const struct ieee802154_ops cc2520_ops = {
 814         .owner = THIS_MODULE,
 815         .start = cc2520_start,
 816         .stop = cc2520_stop,
 817         .xmit_sync = cc2520_tx,
 818         .ed = cc2520_ed,
 819         .set_channel = cc2520_set_channel,
 820         .set_hw_addr_filt = cc2520_filter,
 821         .set_txpower = cc2520_set_txpower,
 822         .set_promiscuous_mode = cc2520_set_promiscuous_mode,
 823 };
 824
 825 static int cc2520_register(struct cc2520_private *priv)
 826 {
 827         int ret = -ENOMEM;
 828
 829         priv->hw = ieee802154_alloc_hw(sizeof(*priv), &cc2520_ops);
 830         if (!priv->hw)
 831                 goto err_ret;
 832
 833         priv->hw->priv = priv;
 834         priv->hw->parent = &priv->spi->dev;
 835         priv->hw->extra_tx_headroom = 0;
 836         ieee802154_random_extended_addr(&priv->hw->phy->perm_extended_addr);
 837
 838         /* We do support only 2.4 Ghz */
 839         priv->hw->phy->supported.channels[0] = 0x7FFF800;
 840         priv->hw->flags = IEEE802154_HW_TX_OMIT_CKSUM | IEEE802154_HW_AFILT |
 841                           IEEE802154_HW_PROMISCUOUS;
 842
 843         priv->hw->phy->flags = WPAN_PHY_FLAG_TXPOWER;
 844
 845         if (!priv->amplified) {
 846                 priv->hw->phy->supported.tx_powers = cc2520_powers;
 847                 priv->hw->phy->supported.tx_powers_size = ARRAY_SIZE(cc2520_powers);
 848                 priv->hw->phy->transmit_power = priv->hw->phy->supported.tx_powers[4];
 849         } else {
 850                 priv->hw->phy->supported.tx_powers = cc2520_cc2591_powers;
 851                 priv->hw->phy->supported.tx_powers_size = ARRAY_SIZE(cc2520_cc2591_powers);
 852                 priv->hw->phy->transmit_power = priv->hw->phy->supported.tx_powers[0];
 853         }
 854
 855         priv->hw->phy->current_channel = 11;
 856
 857         dev_vdbg(&priv->spi->dev, "registered cc2520\n");
 858         ret = ieee802154_register_hw(priv->hw);
 859         if (ret)
 860                 goto err_free_device;
 861
 862         return 0;
 863
 864 err_free_device:
 865         ieee802154_free_hw(priv->hw);
 866 err_ret:
 867         return ret;
 868 }
 869
 870 static void cc2520_fifop_irqwork(struct work_struct *work)
 871 {
 872         struct cc2520_private *priv
 873                 = container_of(work, struct cc2520_private, fifop_irqwork);
 874
 875         dev_dbg(&priv->spi->dev, "fifop interrupt received\n");
 876
 877         if (gpiod_get_value(priv->fifo_pin))
 878                 cc2520_rx(priv);
 879         else
 880                 dev_dbg(&priv->spi->dev, "rxfifo overflow\n");
 881
 882         cc2520_cmd_strobe(priv, CC2520_CMD_SFLUSHRX);
 883         cc2520_cmd_strobe(priv, CC2520_CMD_SFLUSHRX);
 884 }
 885
 886 static irqreturn_t cc2520_fifop_isr(int irq, void *data)
 887 {
 888         struct cc2520_private *priv = data;
 889
 890         schedule_work(&priv->fifop_irqwork);
 891
 892         return IRQ_HANDLED;
 893 }
 894
 895 static irqreturn_t cc2520_sfd_isr(int irq, void *data)
 896 {
 897         struct cc2520_private *priv = data;
 898         unsigned long flags;
 899
 900         spin_lock_irqsave(&priv->lock, flags);
 901         if (priv->is_tx) {
 902                 priv->is_tx = 0;
 903                 spin_unlock_irqrestore(&priv->lock, flags);
 904                 dev_dbg(&priv->spi->dev, "SFD for TX\n");
 905                 complete(&priv->tx_complete);
 906         } else {
 907                 spin_unlock_irqrestore(&priv->lock, flags);
 908                 dev_dbg(&priv->spi->dev, "SFD for RX\n");
 909         }
 910
 911         return IRQ_HANDLED;
 912 }
 913
 914 static int cc2520_hw_init(struct cc2520_private *priv)
 915 {
 916         u8 status = 0, state = 0xff;
 917         int ret;
 918         int timeout = 100;
 919
 920         ret = cc2520_read_register(priv, CC2520_FSMSTAT1, &state);
 921         if (ret)
 922                 goto err_ret;
 923
 924         if (state != STATE_IDLE)
 925                 return -EINVAL;
 926
 927         do {
 928                 ret = cc2520_get_status(priv, &status);
 929                 if (ret)
 930                         goto err_ret;
 931
 932                 if (timeout-- <= 0) {
 933                         dev_err(&priv->spi->dev, "oscillator start failed!\n");
 934                         return -ETIMEDOUT;
 935                 }
 936                 udelay(1);
 937         } while (!(status & CC2520_STATUS_XOSC32M_STABLE));
 938
 939         dev_vdbg(&priv->spi->dev, "oscillator brought up\n");
 940
 941         /* If the CC2520 is connected to a CC2591 amplifier, we must both
 942          * configure GPIOs on the CC2520 to correctly configure the CC2591
 943          * and change a couple settings of the CC2520 to work with the
 944          * amplifier. See section 8 page 17 of TI application note AN065.
 945          * http://www.ti.com/lit/an/swra229a/swra229a.pdf
 946          */
 947         if (priv->amplified) {
 948                 ret = cc2520_write_register(priv, CC2520_AGCCTRL1, 0x16);
 949                 if (ret)
 950                         goto err_ret;
 951
 952                 ret = cc2520_write_register(priv, CC2520_GPIOCTRL0, 0x46);
 953                 if (ret)
 954                         goto err_ret;
 955
 956                 ret = cc2520_write_register(priv, CC2520_GPIOCTRL5, 0x47);
 957                 if (ret)
 958                         goto err_ret;
 959
 960                 ret = cc2520_write_register(priv, CC2520_GPIOPOLARITY, 0x1e);
 961                 if (ret)
 962                         goto err_ret;
 963
 964                 ret = cc2520_write_register(priv, CC2520_TXCTRL, 0xc1);
 965                 if (ret)
 966                         goto err_ret;
 967         } else {
 968                 ret = cc2520_write_register(priv, CC2520_AGCCTRL1, 0x11);
 969                 if (ret)
 970                         goto err_ret;
 971         }
 972
 973         /* Registers default value: section 28.1 in Datasheet */
 974
 975         /* Set the CCA threshold to -50 dBm. This seems to have been copied
 976          * from the TinyOS CC2520 driver and is much higher than the -84 dBm
 977          * threshold suggested in the datasheet.
 978          */
 979         ret = cc2520_write_register(priv, CC2520_CCACTRL0, 0x1A);
 980         if (ret)
 981                 goto err_ret;
 982
 983         ret = cc2520_write_register(priv, CC2520_MDMCTRL0, 0x85);
 984         if (ret)
 985                 goto err_ret;
 986
 987         ret = cc2520_write_register(priv, CC2520_MDMCTRL1, 0x14);
 988         if (ret)
 989                 goto err_ret;
 990
 991         ret = cc2520_write_register(priv, CC2520_RXCTRL, 0x3f);
 992         if (ret)
 993                 goto err_ret;
 994
 995         ret = cc2520_write_register(priv, CC2520_FSCTRL, 0x5a);
 996         if (ret)
 997                 goto err_ret;
 998
 999         ret = cc2520_write_register(priv, CC2520_FSCAL1, 0x2b);
1000         if (ret)
1001                 goto err_ret;
1002
1003         ret = cc2520_write_register(priv, CC2520_ADCTEST0, 0x10);
1004         if (ret)
1005                 goto err_ret;
1006
1007         ret = cc2520_write_register(priv, CC2520_ADCTEST1, 0x0e);
1008         if (ret)
1009                 goto err_ret;
1010
1011         ret = cc2520_write_register(priv, CC2520_ADCTEST2, 0x03);
1012         if (ret)
1013                 goto err_ret;
1014
1015         /* Configure registers correctly for this driver. */
1016         ret = cc2520_write_register(priv, CC2520_FRMCTRL1,
1017                                     FRMCTRL1_SET_RXENMASK_ON_TX |
1018                                     FRMCTRL1_IGNORE_TX_UNDERF);
1019         if (ret)
1020                 goto err_ret;
1021
1022         ret = cc2520_write_register(priv, CC2520_FIFOPCTRL, 127);
1023         if (ret)
1024                 goto err_ret;
1025
1026         return 0;
1027
1028 err_ret:
1029         return ret;
1030 }
1031
1032 static int cc2520_probe(struct spi_device *spi)
1033 {
1034         struct cc2520_private *priv;
1035         struct gpio_desc *fifop;
1036         struct gpio_desc *cca;
1037         struct gpio_desc *sfd;
1038         struct gpio_desc *reset;
1039         struct gpio_desc *vreg;
1040         int ret;
1041
1042         priv = devm_kzalloc(&spi->dev, sizeof(*priv), GFP_KERNEL);
1043         if (!priv)
1044                 return -ENOMEM;
1045
1046         spi_set_drvdata(spi, priv);
1047
1048         /* CC2591 front end for CC2520 */
1049         /* Assumption that CC2591 is not connected */
1050         priv->amplified = false;
1051         if (device_property_read_bool(&spi->dev, "amplified"))
1052                 priv->amplified = true;
1053
1054         priv->spi = spi;
1055
1056         priv->buf = devm_kzalloc(&spi->dev,
1057                                  SPI_COMMAND_BUFFER, GFP_KERNEL);
1058         if (!priv->buf)
1059                 return -ENOMEM;
1060
1061         mutex_init(&priv->buffer_mutex);
1062         INIT_WORK(&priv->fifop_irqwork, cc2520_fifop_irqwork);
1063         spin_lock_init(&priv->lock);
1064         init_completion(&priv->tx_complete);
1065
1066         /* Request all the gpio's */
1067         priv->fifo_pin = devm_gpiod_get(&spi->dev, "fifo", GPIOD_IN);
1068         if (IS_ERR(priv->fifo_pin)) {
1069                 dev_err(&spi->dev, "fifo gpio is not valid\n");
1070                 ret = PTR_ERR(priv->fifo_pin);
1071                 goto err_hw_init;
1072         }
1073
1074         cca = devm_gpiod_get(&spi->dev, "cca", GPIOD_IN);
1075         if (IS_ERR(cca)) {
1076                 dev_err(&spi->dev, "cca gpio is not valid\n");
1077                 ret = PTR_ERR(cca);
1078                 goto err_hw_init;
1079         }
1080
1081         fifop = devm_gpiod_get(&spi->dev, "fifop", GPIOD_IN);
1082         if (IS_ERR(fifop)) {
1083                 dev_err(&spi->dev, "fifop gpio is not valid\n");
1084                 ret = PTR_ERR(fifop);
1085                 goto err_hw_init;
1086         }
1087
1088         sfd = devm_gpiod_get(&spi->dev, "sfd", GPIOD_IN);
1089         if (IS_ERR(sfd)) {
1090                 dev_err(&spi->dev, "sfd gpio is not valid\n");
1091                 ret = PTR_ERR(sfd);
1092                 goto err_hw_init;
1093         }
1094
1095         reset = devm_gpiod_get(&spi->dev, "reset", GPIOD_OUT_LOW);
1096         if (IS_ERR(reset)) {
1097                 dev_err(&spi->dev, "reset gpio is not valid\n");
1098                 ret = PTR_ERR(reset);
1099                 goto err_hw_init;
1100         }
1101
1102         vreg = devm_gpiod_get(&spi->dev, "vreg", GPIOD_OUT_LOW);
1103         if (IS_ERR(vreg)) {
1104                 dev_err(&spi->dev, "vreg gpio is not valid\n");
1105                 ret = PTR_ERR(vreg);
1106                 goto err_hw_init;
1107         }
1108
1109         gpiod_set_value(vreg, HIGH);
1110         usleep_range(100, 150);
1111
1112         gpiod_set_value(reset, HIGH);
1113         usleep_range(200, 250);
1114
1115         ret = cc2520_hw_init(priv);
1116         if (ret)
1117                 goto err_hw_init;
1118
1119         /* Set up fifop interrupt */
1120         ret = devm_request_irq(&spi->dev,
1121                                gpiod_to_irq(fifop),
1122                                cc2520_fifop_isr,
1123                                IRQF_TRIGGER_RISING,
1124                                dev_name(&spi->dev),
1125                                priv);
1126         if (ret) {
1127                 dev_err(&spi->dev, "could not get fifop irq\n");
1128                 goto err_hw_init;
1129         }
1130
1131         /* Set up sfd interrupt */
1132         ret = devm_request_irq(&spi->dev,
1133                                gpiod_to_irq(sfd),
1134                                cc2520_sfd_isr,
1135                                IRQF_TRIGGER_FALLING,
1136                                dev_name(&spi->dev),
1137                                priv);
1138         if (ret) {
1139                 dev_err(&spi->dev, "could not get sfd irq\n");
1140                 goto err_hw_init;
1141         }
1142
1143         ret = cc2520_register(priv);
1144         if (ret)
1145                 goto err_hw_init;
1146
1147         return 0;
1148
1149 err_hw_init:
1150         mutex_destroy(&priv->buffer_mutex);
1151         flush_work(&priv->fifop_irqwork);
1152         return ret;
1153 }
1154
1155 static void cc2520_remove(struct spi_device *spi)
1156 {
1157         struct cc2520_private *priv = spi_get_drvdata(spi);
1158
1159         mutex_destroy(&priv->buffer_mutex);
1160         flush_work(&priv->fifop_irqwork);
1161
1162         ieee802154_unregister_hw(priv->hw);
1163         ieee802154_free_hw(priv->hw);
1164 }
1165
1166 static const struct spi_device_id cc2520_ids[] = {
1167         {"cc2520", },
1168         {},
1169 };
1170 MODULE_DEVICE_TABLE(spi, cc2520_ids);
1171
1172 static const struct of_device_id cc2520_of_ids[] = {
1173         {.compatible = "ti,cc2520", },
1174         {},
1175 };
1176 MODULE_DEVICE_TABLE(of, cc2520_of_ids);
1177
1178 /* SPI driver structure */
1179 static struct spi_driver cc2520_driver = {
1180         .driver = {
1181                 .name = "cc2520",
1182                 .of_match_table = cc2520_of_ids,
1183         },
1184         .id_table = cc2520_ids,
1185         .probe = cc2520_probe,
1186         .remove = cc2520_remove,
1187 };
1188 module_spi_driver(cc2520_driver);
1189
1190 MODULE_AUTHOR("Varka Bhadram <varkab@cdac.in>");
1191 MODULE_DESCRIPTION("CC2520 Transceiver Driver");
1192 MODULE_LICENSE("GPL v2");