drivers/net/wan/fsl_ucc_hdlc.c

   1 /* Freescale QUICC Engine HDLC Device Driver
   2  *
   3  * Copyright 2016 Freescale Semiconductor Inc.
   4  *
   5  * This program is free software; you can redistribute  it and/or modify it
   6  * under  the terms of  the GNU General  Public License as published by the
   7  * Free Software Foundation;  either version 2 of the  License, or (at your
   8  * option) any later version.
   9  */
  10
  11 #include <linux/delay.h>
  12 #include <linux/dma-mapping.h>
  13 #include <linux/hdlc.h>
  14 #include <linux/init.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/io.h>
  17 #include <linux/irq.h>
  18 #include <linux/kernel.h>
  19 #include <linux/module.h>
  20 #include <linux/netdevice.h>
  21 #include <linux/of_address.h>
  22 #include <linux/of_irq.h>
  23 #include <linux/of_platform.h>
  24 #include <linux/platform_device.h>
  25 #include <linux/sched.h>
  26 #include <linux/skbuff.h>
  27 #include <linux/slab.h>
  28 #include <linux/spinlock.h>
  29 #include <linux/stddef.h>
  30 #include <soc/fsl/qe/qe_tdm.h>
  31 #include <uapi/linux/if_arp.h>
  32
  33 #include "fsl_ucc_hdlc.h"
  34
  35 #define DRV_DESC "Freescale QE UCC HDLC Driver"
  36 #define DRV_NAME "ucc_hdlc"
  37
  38 #define TDM_PPPOHT_SLIC_MAXIN
  39 #define BROKEN_FRAME_INFO
  40
  41 static struct ucc_tdm_info utdm_primary_info = {
  42         .uf_info = {
  43                 .tsa = 0,
  44                 .cdp = 0,
  45                 .cds = 1,
  46                 .ctsp = 1,
  47                 .ctss = 1,
  48                 .revd = 0,
  49                 .urfs = 256,
  50                 .utfs = 256,
  51                 .urfet = 128,
  52                 .urfset = 192,
  53                 .utfet = 128,
  54                 .utftt = 0x40,
  55                 .ufpt = 256,
  56                 .mode = UCC_FAST_PROTOCOL_MODE_HDLC,
  57                 .ttx_trx = UCC_FAST_GUMR_TRANSPARENT_TTX_TRX_NORMAL,
  58                 .tenc = UCC_FAST_TX_ENCODING_NRZ,
  59                 .renc = UCC_FAST_RX_ENCODING_NRZ,
  60                 .tcrc = UCC_FAST_16_BIT_CRC,
  61                 .synl = UCC_FAST_SYNC_LEN_NOT_USED,
  62         },
  63
  64         .si_info = {
  65 #ifdef TDM_PPPOHT_SLIC_MAXIN
  66                 .simr_rfsd = 1,
  67                 .simr_tfsd = 2,
  68 #else
  69                 .simr_rfsd = 0,
  70                 .simr_tfsd = 0,
  71 #endif
  72                 .simr_crt = 0,
  73                 .simr_sl = 0,
  74                 .simr_ce = 1,
  75                 .simr_fe = 1,
  76                 .simr_gm = 0,
  77         },
  78 };
  79
  80 static struct ucc_tdm_info utdm_info[MAX_HDLC_NUM];
  81
  82 static int uhdlc_init(struct ucc_hdlc_private *priv)
  83 {
  84         struct ucc_tdm_info *ut_info;
  85         struct ucc_fast_info *uf_info;
  86         u32 cecr_subblock;
  87         u16 bd_status;
  88         int ret, i;
  89         void *bd_buffer;
  90         dma_addr_t bd_dma_addr;
  91         u32 riptr;
  92         u32 tiptr;
  93         u32 gumr;
  94
  95         ut_info = priv->ut_info;
  96         uf_info = &ut_info->uf_info;
  97
  98         if (priv->tsa) {
  99                 uf_info->tsa = 1;
 100                 uf_info->ctsp = 1;
 101         }
 102         uf_info->uccm_mask = ((UCC_HDLC_UCCE_RXB | UCC_HDLC_UCCE_RXF |
 103                                 UCC_HDLC_UCCE_TXB) << 16);
 104
 105         ret = ucc_fast_init(uf_info, &priv->uccf);
 106         if (ret) {
 107                 dev_err(priv->dev, "Failed to init uccf.");
 108                 return ret;
 109         }
 110
 111         priv->uf_regs = priv->uccf->uf_regs;
 112         ucc_fast_disable(priv->uccf, COMM_DIR_RX | COMM_DIR_TX);
 113
 114         /* Loopback mode */
 115         if (priv->loopback) {
 116                 dev_info(priv->dev, "Loopback Mode\n");
 117                 gumr = ioread32be(&priv->uf_regs->gumr);
 118                 gumr |= (UCC_FAST_GUMR_LOOPBACK | UCC_FAST_GUMR_CDS |
 119                          UCC_FAST_GUMR_TCI);
 120                 gumr &= ~(UCC_FAST_GUMR_CTSP | UCC_FAST_GUMR_RSYN);
 121                 iowrite32be(gumr, &priv->uf_regs->gumr);
 122         }
 123
 124         /* Initialize SI */
 125         if (priv->tsa)
 126                 ucc_tdm_init(priv->utdm, priv->ut_info);
 127
 128         /* Write to QE CECR, UCCx channel to Stop Transmission */
 129         cecr_subblock = ucc_fast_get_qe_cr_subblock(uf_info->ucc_num);
 130         ret = qe_issue_cmd(QE_STOP_TX, cecr_subblock,
 131                            QE_CR_PROTOCOL_UNSPECIFIED, 0);
 132
 133         /* Set UPSMR normal mode (need fixed)*/
 134         iowrite32be(0, &priv->uf_regs->upsmr);
 135
 136         priv->rx_ring_size = RX_BD_RING_LEN;
 137         priv->tx_ring_size = TX_BD_RING_LEN;
 138         /* Alloc Rx BD */
 139         priv->rx_bd_base = dma_alloc_coherent(priv->dev,
 140                         RX_BD_RING_LEN * sizeof(struct qe_bd *),
 141                         &priv->dma_rx_bd, GFP_KERNEL);
 142
 143         if (!priv->rx_bd_base) {
 144                 dev_err(priv->dev, "Cannot allocate MURAM memory for RxBDs\n");
 145                 ret = -ENOMEM;
 146                 goto free_uccf;
 147         }
 148
 149         /* Alloc Tx BD */
 150         priv->tx_bd_base = dma_alloc_coherent(priv->dev,
 151                         TX_BD_RING_LEN * sizeof(struct qe_bd *),
 152                         &priv->dma_tx_bd, GFP_KERNEL);
 153
 154         if (!priv->tx_bd_base) {
 155                 dev_err(priv->dev, "Cannot allocate MURAM memory for TxBDs\n");
 156                 ret = -ENOMEM;
 157                 goto free_rx_bd;
 158         }
 159
 160         /* Alloc parameter ram for ucc hdlc */
 161         priv->ucc_pram_offset = qe_muram_alloc(sizeof(priv->ucc_pram),
 162                                 ALIGNMENT_OF_UCC_HDLC_PRAM);
 163
 164         if (priv->ucc_pram_offset < 0) {
 165                 dev_err(priv->dev, "Can not allocate MURAM for hdlc parameter.\n");
 166                 ret = -ENOMEM;
 167                 goto free_tx_bd;
 168         }
 169
 170         priv->rx_skbuff = kzalloc(priv->rx_ring_size * sizeof(*priv->rx_skbuff),
 171                                   GFP_KERNEL);
 172         if (!priv->rx_skbuff)
 173                 goto free_ucc_pram;
 174
 175         priv->tx_skbuff = kzalloc(priv->tx_ring_size * sizeof(*priv->tx_skbuff),
 176                                   GFP_KERNEL);
 177         if (!priv->tx_skbuff)
 178                 goto free_rx_skbuff;
 179
 180         priv->skb_curtx = 0;
 181         priv->skb_dirtytx = 0;
 182         priv->curtx_bd = priv->tx_bd_base;
 183         priv->dirty_tx = priv->tx_bd_base;
 184         priv->currx_bd = priv->rx_bd_base;
 185         priv->currx_bdnum = 0;
 186
 187         /* init parameter base */
 188         cecr_subblock = ucc_fast_get_qe_cr_subblock(uf_info->ucc_num);
 189         ret = qe_issue_cmd(QE_ASSIGN_PAGE_TO_DEVICE, cecr_subblock,
 190                            QE_CR_PROTOCOL_UNSPECIFIED, priv->ucc_pram_offset);
 191
 192         priv->ucc_pram = (struct ucc_hdlc_param __iomem *)
 193                                         qe_muram_addr(priv->ucc_pram_offset);
 194
 195         /* Zero out parameter ram */
 196         memset_io(priv->ucc_pram, 0, sizeof(struct ucc_hdlc_param));
 197
 198         /* Alloc riptr, tiptr */
 199         riptr = qe_muram_alloc(32, 32);
 200         if (riptr < 0) {
 201                 dev_err(priv->dev, "Cannot allocate MURAM mem for Receive internal temp data pointer\n");
 202                 ret = -ENOMEM;
 203                 goto free_tx_skbuff;
 204         }
 205
 206         tiptr = qe_muram_alloc(32, 32);
 207         if (tiptr < 0) {
 208                 dev_err(priv->dev, "Cannot allocate MURAM mem for Transmit internal temp data pointer\n");
 209                 ret = -ENOMEM;
 210                 goto free_riptr;
 211         }
 212
 213         /* Set RIPTR, TIPTR */
 214         iowrite16be(riptr, &priv->ucc_pram->riptr);
 215         iowrite16be(tiptr, &priv->ucc_pram->tiptr);
 216
 217         /* Set MRBLR */
 218         iowrite16be(MAX_RX_BUF_LENGTH, &priv->ucc_pram->mrblr);
 219
 220         /* Set RBASE, TBASE */
 221         iowrite32be(priv->dma_rx_bd, &priv->ucc_pram->rbase);
 222         iowrite32be(priv->dma_tx_bd, &priv->ucc_pram->tbase);
 223
 224         /* Set RSTATE, TSTATE */
 225         iowrite32be(BMR_GBL | BMR_BIG_ENDIAN, &priv->ucc_pram->rstate);
 226         iowrite32be(BMR_GBL | BMR_BIG_ENDIAN, &priv->ucc_pram->tstate);
 227
 228         /* Set C_MASK, C_PRES for 16bit CRC */
 229         iowrite32be(CRC_16BIT_MASK, &priv->ucc_pram->c_mask);
 230         iowrite32be(CRC_16BIT_PRES, &priv->ucc_pram->c_pres);
 231
 232         iowrite16be(MAX_FRAME_LENGTH, &priv->ucc_pram->mflr);
 233         iowrite16be(DEFAULT_RFTHR, &priv->ucc_pram->rfthr);
 234         iowrite16be(DEFAULT_RFTHR, &priv->ucc_pram->rfcnt);
 235         iowrite16be(DEFAULT_ADDR_MASK, &priv->ucc_pram->hmask);
 236         iowrite16be(DEFAULT_HDLC_ADDR, &priv->ucc_pram->haddr1);
 237         iowrite16be(DEFAULT_HDLC_ADDR, &priv->ucc_pram->haddr2);
 238         iowrite16be(DEFAULT_HDLC_ADDR, &priv->ucc_pram->haddr3);
 239         iowrite16be(DEFAULT_HDLC_ADDR, &priv->ucc_pram->haddr4);
 240
 241         /* Get BD buffer */
 242         bd_buffer = dma_alloc_coherent(priv->dev,
 243                                        (RX_BD_RING_LEN + TX_BD_RING_LEN) *
 244                                        MAX_RX_BUF_LENGTH,
 245                                        &bd_dma_addr, GFP_KERNEL);
 246
 247         if (!bd_buffer) {
 248                 dev_err(priv->dev, "Could not allocate buffer descriptors\n");
 249                 ret = -ENOMEM;
 250                 goto free_tiptr;
 251         }
 252
 253         memset(bd_buffer, 0, (RX_BD_RING_LEN + TX_BD_RING_LEN)
 254                         * MAX_RX_BUF_LENGTH);
 255
 256         priv->rx_buffer = bd_buffer;
 257         priv->tx_buffer = bd_buffer + RX_BD_RING_LEN * MAX_RX_BUF_LENGTH;
 258
 259         priv->dma_rx_addr = bd_dma_addr;
 260         priv->dma_tx_addr = bd_dma_addr + RX_BD_RING_LEN * MAX_RX_BUF_LENGTH;
 261
 262         for (i = 0; i < RX_BD_RING_LEN; i++) {
 263                 if (i < (RX_BD_RING_LEN - 1))
 264                         bd_status = R_E_S | R_I_S;
 265                 else
 266                         bd_status = R_E_S | R_I_S | R_W_S;
 267
 268                 iowrite16be(bd_status, &priv->rx_bd_base[i].status);
 269                 iowrite32be(priv->dma_rx_addr + i * MAX_RX_BUF_LENGTH,
 270                             &priv->rx_bd_base[i].buf);
 271         }
 272
 273         for (i = 0; i < TX_BD_RING_LEN; i++) {
 274                 if (i < (TX_BD_RING_LEN - 1))
 275                         bd_status =  T_I_S | T_TC_S;
 276                 else
 277                         bd_status =  T_I_S | T_TC_S | T_W_S;
 278
 279                 iowrite16be(bd_status, &priv->tx_bd_base[i].status);
 280                 iowrite32be(priv->dma_tx_addr + i * MAX_RX_BUF_LENGTH,
 281                             &priv->tx_bd_base[i].buf);
 282         }
 283
 284         return 0;
 285
 286 free_tiptr:
 287         qe_muram_free(tiptr);
 288 free_riptr:
 289         qe_muram_free(riptr);
 290 free_tx_skbuff:
 291         kfree(priv->tx_skbuff);
 292 free_rx_skbuff:
 293         kfree(priv->rx_skbuff);
 294 free_ucc_pram:
 295         qe_muram_free(priv->ucc_pram_offset);
 296 free_tx_bd:
 297         dma_free_coherent(priv->dev,
 298                           TX_BD_RING_LEN * sizeof(struct qe_bd *),
 299                           priv->tx_bd_base, priv->dma_tx_bd);
 300 free_rx_bd:
 301         dma_free_coherent(priv->dev,
 302                           RX_BD_RING_LEN * sizeof(struct qe_bd *),
 303                           priv->rx_bd_base, priv->dma_rx_bd);
 304 free_uccf:
 305         ucc_fast_free(priv->uccf);
 306
 307         return ret;
 308 }
 309
 310 static netdev_tx_t ucc_hdlc_tx(struct sk_buff *skb, struct net_device *dev)
 311 {
 312         hdlc_device *hdlc = dev_to_hdlc(dev);
 313         struct ucc_hdlc_private *priv = (struct ucc_hdlc_private *)hdlc->priv;
 314         struct qe_bd __iomem *bd;
 315         u16 bd_status;
 316         unsigned long flags;
 317         u8 *send_buf;
 318         int i;
 319         u16 *proto_head;
 320
 321         switch (dev->type) {
 322         case ARPHRD_RAWHDLC:
 323                 if (skb_headroom(skb) < HDLC_HEAD_LEN) {
 324                         dev->stats.tx_dropped++;
 325                         dev_kfree_skb(skb);
 326                         netdev_err(dev, "No enough space for hdlc head\n");
 327                         return -ENOMEM;
 328                 }
 329
 330                 skb_push(skb, HDLC_HEAD_LEN);
 331
 332                 proto_head = (u16 *)skb->data;
 333                 *proto_head = htons(DEFAULT_HDLC_HEAD);
 334
 335                 dev->stats.tx_bytes += skb->len;
 336                 break;
 337
 338         case ARPHRD_PPP:
 339                 proto_head = (u16 *)skb->data;
 340                 if (*proto_head != htons(DEFAULT_PPP_HEAD)) {
 341                         dev->stats.tx_dropped++;
 342                         dev_kfree_skb(skb);
 343                         netdev_err(dev, "Wrong ppp header\n");
 344                         return -ENOMEM;
 345                 }
 346
 347                 dev->stats.tx_bytes += skb->len;
 348                 break;
 349
 350         default:
 351                 dev->stats.tx_dropped++;
 352                 dev_kfree_skb(skb);
 353                 return -ENOMEM;
 354         }
 355
 356         pr_info("Tx data skb->len:%d ", skb->len);
 357         send_buf = (u8 *)skb->data;
 358         pr_info("\nTransmitted data:\n");
 359         for (i = 0; i < 16; i++) {
 360                 if (i == skb->len)
 361                         pr_info("++++");
 362                 else
 363                 pr_info("%02x\n", send_buf[i]);
 364         }
 365         spin_lock_irqsave(&priv->lock, flags);
 366
 367         /* Start from the next BD that should be filled */
 368         bd = priv->curtx_bd;
 369         bd_status = ioread16be(&bd->status);
 370         /* Save the skb pointer so we can free it later */
 371         priv->tx_skbuff[priv->skb_curtx] = skb;
 372
 373         /* Update the current skb pointer (wrapping if this was the last) */
 374         priv->skb_curtx =
 375             (priv->skb_curtx + 1) & TX_RING_MOD_MASK(TX_BD_RING_LEN);
 376
 377         /* copy skb data to tx buffer for sdma processing */
 378         memcpy(priv->tx_buffer + (be32_to_cpu(bd->buf) - priv->dma_tx_addr),
 379                skb->data, skb->len);
 380
 381         /* set bd status and length */
 382         bd_status = (bd_status & T_W_S) | T_R_S | T_I_S | T_L_S | T_TC_S;
 383
 384         iowrite16be(bd_status, &bd->status);
 385         iowrite16be(skb->len, &bd->length);
 386
 387         /* Move to next BD in the ring */
 388         if (!(bd_status & T_W_S))
 389                 bd += 1;
 390         else
 391                 bd = priv->tx_bd_base;
 392
 393         if (bd == priv->dirty_tx) {
 394                 if (!netif_queue_stopped(dev))
 395                         netif_stop_queue(dev);
 396         }
 397
 398         priv->curtx_bd = bd;
 399
 400         spin_unlock_irqrestore(&priv->lock, flags);
 401
 402         return NETDEV_TX_OK;
 403 }
 404
 405 static int hdlc_tx_done(struct ucc_hdlc_private *priv)
 406 {
 407         /* Start from the next BD that should be filled */
 408         struct net_device *dev = priv->ndev;
 409         struct qe_bd *bd;               /* BD pointer */
 410         u16 bd_status;
 411
 412         bd = priv->dirty_tx;
 413         bd_status = ioread16be(&bd->status);
 414
 415         /* Normal processing. */
 416         while ((bd_status & T_R_S) == 0) {
 417                 struct sk_buff *skb;
 418
 419                 /* BD contains already transmitted buffer.   */
 420                 /* Handle the transmitted buffer and release */
 421                 /* the BD to be used with the current frame  */
 422
 423                 skb = priv->tx_skbuff[priv->skb_dirtytx];
 424                 if (!skb)
 425                         break;
 426                 pr_info("TxBD: %x\n", bd_status);
 427                 dev->stats.tx_packets++;
 428                 memset(priv->tx_buffer +
 429                        (be32_to_cpu(bd->buf) - priv->dma_tx_addr),
 430                        0, skb->len);
 431                 dev_kfree_skb_irq(skb);
 432
 433                 priv->tx_skbuff[priv->skb_dirtytx] = NULL;
 434                 priv->skb_dirtytx =
 435                     (priv->skb_dirtytx +
 436                      1) & TX_RING_MOD_MASK(TX_BD_RING_LEN);
 437
 438                 /* We freed a buffer, so now we can restart transmission */
 439                 if (netif_queue_stopped(dev))
 440                         netif_wake_queue(dev);
 441
 442                 /* Advance the confirmation BD pointer */
 443                 if (!(bd_status & T_W_S))
 444                         bd += 1;
 445                 else
 446                         bd = priv->tx_bd_base;
 447                 bd_status = ioread16be(&bd->status);
 448         }
 449         priv->dirty_tx = bd;
 450
 451         return 0;
 452 }
 453
 454 static int hdlc_rx_done(struct ucc_hdlc_private *priv, int rx_work_limit)
 455 {
 456         struct net_device *dev = priv->ndev;
 457         struct sk_buff *skb;
 458         hdlc_device *hdlc = dev_to_hdlc(dev);
 459         struct qe_bd *bd;
 460         u32 bd_status;
 461         u16 length, howmany = 0;
 462         u8 *bdbuffer;
 463         int i;
 464         static int entry;
 465
 466         bd = priv->currx_bd;
 467         bd_status = ioread16be(&bd->status);
 468
 469         /* while there are received buffers and BD is full (~R_E) */
 470         while (!((bd_status & (R_E_S)) || (--rx_work_limit < 0))) {
 471                 if (bd_status & R_OV_S)
 472                         dev->stats.rx_over_errors++;
 473                 if (bd_status & R_CR_S) {
 474 #ifdef BROKEN_FRAME_INFO
 475                         pr_info("Broken Frame with RxBD: %x\n", bd_status);
 476 #endif
 477                         dev->stats.rx_crc_errors++;
 478                         dev->stats.rx_dropped++;
 479                         goto recycle;
 480                 }
 481                 bdbuffer = priv->rx_buffer +
 482                         (priv->currx_bdnum * MAX_RX_BUF_LENGTH);
 483                 length = ioread16be(&bd->length);
 484
 485                 pr_info("Received data length:%d", length);
 486                 pr_info("while entry times:%d", entry++);
 487
 488                 pr_info("\nReceived data:\n");
 489                 for (i = 0; (i < 16); i++) {
 490                         if (i == length)
 491                                 pr_info("++++");
 492                         else
 493                         pr_info("%02x\n", bdbuffer[i]);
 494                 }
 495
 496                 switch (dev->type) {
 497                 case ARPHRD_RAWHDLC:
 498                         bdbuffer += HDLC_HEAD_LEN;
 499                         length -= (HDLC_HEAD_LEN + HDLC_CRC_SIZE);
 500
 501                         skb = dev_alloc_skb(length);
 502                         if (!skb) {
 503                                 dev->stats.rx_dropped++;
 504                                 return -ENOMEM;
 505                         }
 506
 507                         skb_put(skb, length);
 508                         skb->len = length;
 509                         skb->dev = dev;
 510                         memcpy(skb->data, bdbuffer, length);
 511                         break;
 512
 513                 case ARPHRD_PPP:
 514                         length -= HDLC_CRC_SIZE;
 515
 516                         skb = dev_alloc_skb(length);
 517                         if (!skb) {
 518                                 dev->stats.rx_dropped++;
 519                                 return -ENOMEM;
 520                         }
 521
 522                         skb_put(skb, length);
 523                         skb->len = length;
 524                         skb->dev = dev;
 525                         memcpy(skb->data, bdbuffer, length);
 526                         break;
 527                 }
 528
 529                 dev->stats.rx_packets++;
 530                 dev->stats.rx_bytes += skb->len;
 531                 howmany++;
 532                 if (hdlc->proto)
 533                         skb->protocol = hdlc_type_trans(skb, dev);
 534                 pr_info("skb->protocol:%x\n", skb->protocol);
 535                 netif_receive_skb(skb);
 536
 537 recycle:
 538                 iowrite16be(bd_status | R_E_S | R_I_S, &bd->status);
 539
 540                 /* update to point at the next bd */
 541                 if (bd_status & R_W_S) {
 542                         priv->currx_bdnum = 0;
 543                         bd = priv->rx_bd_base;
 544                 } else {
 545                         if (priv->currx_bdnum < (RX_BD_RING_LEN - 1))
 546                                 priv->currx_bdnum += 1;
 547                         else
 548                                 priv->currx_bdnum = RX_BD_RING_LEN - 1;
 549
 550                         bd += 1;
 551                 }
 552
 553                 bd_status = ioread16be(&bd->status);
 554         }
 555
 556         priv->currx_bd = bd;
 557         return howmany;
 558 }
 559
 560 static int ucc_hdlc_poll(struct napi_struct *napi, int budget)
 561 {
 562         struct ucc_hdlc_private *priv = container_of(napi,
 563                                                      struct ucc_hdlc_private,
 564                                                      napi);
 565         int howmany;
 566
 567         /* Tx event processing */
 568         spin_lock(&priv->lock);
 569                 hdlc_tx_done(priv);
 570         spin_unlock(&priv->lock);
 571
 572         howmany = 0;
 573         howmany += hdlc_rx_done(priv, budget - howmany);
 574
 575         if (howmany < budget) {
 576                 napi_complete_done(napi, howmany);
 577                 qe_setbits32(priv->uccf->p_uccm,
 578                              (UCCE_HDLC_RX_EVENTS | UCCE_HDLC_TX_EVENTS) << 16);
 579         }
 580
 581         return howmany;
 582 }
 583
 584 static irqreturn_t ucc_hdlc_irq_handler(int irq, void *dev_id)
 585 {
 586         struct ucc_hdlc_private *priv = (struct ucc_hdlc_private *)dev_id;
 587         struct net_device *dev = priv->ndev;
 588         struct ucc_fast_private *uccf;
 589         struct ucc_tdm_info *ut_info;
 590         u32 ucce;
 591         u32 uccm;
 592
 593         ut_info = priv->ut_info;
 594         uccf = priv->uccf;
 595
 596         ucce = ioread32be(uccf->p_ucce);
 597         uccm = ioread32be(uccf->p_uccm);
 598         ucce &= uccm;
 599         iowrite32be(ucce, uccf->p_ucce);
 600         pr_info("irq ucce:%x\n", ucce);
 601         if (!ucce)
 602                 return IRQ_NONE;
 603
 604         if ((ucce >> 16) & (UCCE_HDLC_RX_EVENTS | UCCE_HDLC_TX_EVENTS)) {
 605                 if (napi_schedule_prep(&priv->napi)) {
 606                         uccm &= ~((UCCE_HDLC_RX_EVENTS | UCCE_HDLC_TX_EVENTS)
 607                                   << 16);
 608                         iowrite32be(uccm, uccf->p_uccm);
 609                         __napi_schedule(&priv->napi);
 610                 }
 611         }
 612
 613         /* Errors and other events */
 614         if (ucce >> 16 & UCC_HDLC_UCCE_BSY)
 615                 dev->stats.rx_errors++;
 616         if (ucce >> 16 & UCC_HDLC_UCCE_TXE)
 617                 dev->stats.tx_errors++;
 618
 619         return IRQ_HANDLED;
 620 }
 621
 622 static int uhdlc_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 623 {
 624         const size_t size = sizeof(te1_settings);
 625         te1_settings line;
 626         struct ucc_hdlc_private *priv = netdev_priv(dev);
 627
 628         if (cmd != SIOCWANDEV)
 629                 return hdlc_ioctl(dev, ifr, cmd);
 630
 631         switch (ifr->ifr_settings.type) {
 632         case IF_GET_IFACE:
 633                 ifr->ifr_settings.type = IF_IFACE_E1;
 634                 if (ifr->ifr_settings.size < size) {
 635                         ifr->ifr_settings.size = size; /* data size wanted */
 636                         return -ENOBUFS;
 637                 }
 638                 memset(&line, 0, sizeof(line));
 639                 line.clock_type = priv->clocking;
 640
 641                 if (copy_to_user(ifr->ifr_settings.ifs_ifsu.sync, &line, size))
 642                         return -EFAULT;
 643                 return 0;
 644
 645         default:
 646                 return hdlc_ioctl(dev, ifr, cmd);
 647         }
 648 }
 649
 650 static int uhdlc_open(struct net_device *dev)
 651 {
 652         u32 cecr_subblock;
 653         hdlc_device *hdlc = dev_to_hdlc(dev);
 654         struct ucc_hdlc_private *priv = hdlc->priv;
 655         struct ucc_tdm *utdm = priv->utdm;
 656
 657         if (priv->hdlc_busy != 1) {
 658                 if (request_irq(priv->ut_info->uf_info.irq,
 659                                 ucc_hdlc_irq_handler, 0, "hdlc", priv))
 660                         return -ENODEV;
 661
 662                 cecr_subblock = ucc_fast_get_qe_cr_subblock(
 663                                         priv->ut_info->uf_info.ucc_num);
 664
 665                 qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock,
 666                              QE_CR_PROTOCOL_UNSPECIFIED, 0);
 667
 668                 ucc_fast_enable(priv->uccf, COMM_DIR_RX | COMM_DIR_TX);
 669
 670                 /* Enable the TDM port */
 671                 if (priv->tsa)
 672                         utdm->si_regs->siglmr1_h |= (0x1 << utdm->tdm_port);
 673
 674                 priv->hdlc_busy = 1;
 675                 netif_device_attach(priv->ndev);
 676                 napi_enable(&priv->napi);
 677                 netif_start_queue(dev);
 678                 hdlc_open(dev);
 679         }
 680
 681         return 0;
 682 }
 683
 684 static void uhdlc_memclean(struct ucc_hdlc_private *priv)
 685 {
 686         qe_muram_free(priv->ucc_pram->riptr);
 687         qe_muram_free(priv->ucc_pram->tiptr);
 688
 689         if (priv->rx_bd_base) {
 690                 dma_free_coherent(priv->dev,
 691                                   RX_BD_RING_LEN * sizeof(struct qe_bd *),
 692                                   priv->rx_bd_base, priv->dma_rx_bd);
 693
 694                 priv->rx_bd_base = NULL;
 695                 priv->dma_rx_bd = 0;
 696         }
 697
 698         if (priv->tx_bd_base) {
 699                 dma_free_coherent(priv->dev,
 700                                   TX_BD_RING_LEN * sizeof(struct qe_bd *),
 701                                   priv->tx_bd_base, priv->dma_tx_bd);
 702
 703                 priv->tx_bd_base = NULL;
 704                 priv->dma_tx_bd = 0;
 705         }
 706
 707         if (priv->ucc_pram) {
 708                 qe_muram_free(priv->ucc_pram_offset);
 709                 priv->ucc_pram = NULL;
 710                 priv->ucc_pram_offset = 0;
 711          }
 712
 713         kfree(priv->rx_skbuff);
 714         priv->rx_skbuff = NULL;
 715
 716         kfree(priv->tx_skbuff);
 717         priv->tx_skbuff = NULL;
 718
 719         if (priv->uf_regs) {
 720                 iounmap(priv->uf_regs);
 721                 priv->uf_regs = NULL;
 722         }
 723
 724         if (priv->uccf) {
 725                 ucc_fast_free(priv->uccf);
 726                 priv->uccf = NULL;
 727         }
 728
 729         if (priv->rx_buffer) {
 730                 dma_free_coherent(priv->dev,
 731                                   RX_BD_RING_LEN * MAX_RX_BUF_LENGTH,
 732                                   priv->rx_buffer, priv->dma_rx_addr);
 733                 priv->rx_buffer = NULL;
 734                 priv->dma_rx_addr = 0;
 735         }
 736
 737         if (priv->tx_buffer) {
 738                 dma_free_coherent(priv->dev,
 739                                   TX_BD_RING_LEN * MAX_RX_BUF_LENGTH,
 740                                   priv->tx_buffer, priv->dma_tx_addr);
 741                 priv->tx_buffer = NULL;
 742                 priv->dma_tx_addr = 0;
 743         }
 744 }
 745
 746 static int uhdlc_close(struct net_device *dev)
 747 {
 748         struct ucc_hdlc_private *priv = dev_to_hdlc(dev)->priv;
 749         struct ucc_tdm *utdm = priv->utdm;
 750         u32 cecr_subblock;
 751
 752         napi_disable(&priv->napi);
 753         cecr_subblock = ucc_fast_get_qe_cr_subblock(
 754                                 priv->ut_info->uf_info.ucc_num);
 755
 756         qe_issue_cmd(QE_GRACEFUL_STOP_TX, cecr_subblock,
 757                      (u8)QE_CR_PROTOCOL_UNSPECIFIED, 0);
 758         qe_issue_cmd(QE_CLOSE_RX_BD, cecr_subblock,
 759                      (u8)QE_CR_PROTOCOL_UNSPECIFIED, 0);
 760
 761         if (priv->tsa)
 762                 utdm->si_regs->siglmr1_h &= ~(0x1 << utdm->tdm_port);
 763
 764         ucc_fast_disable(priv->uccf, COMM_DIR_RX | COMM_DIR_TX);
 765
 766         free_irq(priv->ut_info->uf_info.irq, priv);
 767         netif_stop_queue(dev);
 768         priv->hdlc_busy = 0;
 769
 770         return 0;
 771 }
 772
 773 static int ucc_hdlc_attach(struct net_device *dev, unsigned short encoding,
 774                            unsigned short parity)
 775 {
 776         struct ucc_hdlc_private *priv = dev_to_hdlc(dev)->priv;
 777
 778         if (encoding != ENCODING_NRZ &&
 779             encoding != ENCODING_NRZI)
 780                 return -EINVAL;
 781
 782         if (parity != PARITY_NONE &&
 783             parity != PARITY_CRC32_PR1_CCITT &&
 784             parity != PARITY_CRC16_PR1_CCITT)
 785                 return -EINVAL;
 786
 787         priv->encoding = encoding;
 788         priv->parity = parity;
 789
 790         return 0;
 791 }
 792
 793 #ifdef CONFIG_PM
 794 static void store_clk_config(struct ucc_hdlc_private *priv)
 795 {
 796         struct qe_mux *qe_mux_reg = &qe_immr->qmx;
 797
 798         /* store si clk */
 799         priv->cmxsi1cr_h = ioread32be(&qe_mux_reg->cmxsi1cr_h);
 800         priv->cmxsi1cr_l = ioread32be(&qe_mux_reg->cmxsi1cr_l);
 801
 802         /* store si sync */
 803         priv->cmxsi1syr = ioread32be(&qe_mux_reg->cmxsi1syr);
 804
 805         /* store ucc clk */
 806         memcpy_fromio(priv->cmxucr, qe_mux_reg->cmxucr, 4 * sizeof(u32));
 807 }
 808
 809 static void resume_clk_config(struct ucc_hdlc_private *priv)
 810 {
 811         struct qe_mux *qe_mux_reg = &qe_immr->qmx;
 812
 813         memcpy_toio(qe_mux_reg->cmxucr, priv->cmxucr, 4 * sizeof(u32));
 814
 815         iowrite32be(priv->cmxsi1cr_h, &qe_mux_reg->cmxsi1cr_h);
 816         iowrite32be(priv->cmxsi1cr_l, &qe_mux_reg->cmxsi1cr_l);
 817
 818         iowrite32be(priv->cmxsi1syr, &qe_mux_reg->cmxsi1syr);
 819 }
 820
 821 static int uhdlc_suspend(struct device *dev)
 822 {
 823         struct ucc_hdlc_private *priv = dev_get_drvdata(dev);
 824         struct ucc_tdm_info *ut_info;
 825         struct ucc_fast __iomem *uf_regs;
 826
 827         if (!priv)
 828                 return -EINVAL;
 829
 830         if (!netif_running(priv->ndev))
 831                 return 0;
 832
 833         netif_device_detach(priv->ndev);
 834         napi_disable(&priv->napi);
 835
 836         ut_info = priv->ut_info;
 837         uf_regs = priv->uf_regs;
 838
 839         /* backup gumr guemr*/
 840         priv->gumr = ioread32be(&uf_regs->gumr);
 841         priv->guemr = ioread8(&uf_regs->guemr);
 842
 843         priv->ucc_pram_bak = kmalloc(sizeof(*priv->ucc_pram_bak),
 844                                         GFP_KERNEL);
 845         if (!priv->ucc_pram_bak)
 846                 return -ENOMEM;
 847
 848         /* backup HDLC parameter */
 849         memcpy_fromio(priv->ucc_pram_bak, priv->ucc_pram,
 850                       sizeof(struct ucc_hdlc_param));
 851
 852         /* store the clk configuration */
 853         store_clk_config(priv);
 854
 855         /* save power */
 856         ucc_fast_disable(priv->uccf, COMM_DIR_RX | COMM_DIR_TX);
 857
 858         dev_dbg(dev, "ucc hdlc suspend\n");
 859         return 0;
 860 }
 861
 862 static int uhdlc_resume(struct device *dev)
 863 {
 864         struct ucc_hdlc_private *priv = dev_get_drvdata(dev);
 865         struct ucc_tdm *utdm;
 866         struct ucc_tdm_info *ut_info;
 867         struct ucc_fast __iomem *uf_regs;
 868         struct ucc_fast_private *uccf;
 869         struct ucc_fast_info *uf_info;
 870         int ret, i;
 871         u32 cecr_subblock;
 872         u16 bd_status;
 873
 874         if (!priv)
 875                 return -EINVAL;
 876
 877         if (!netif_running(priv->ndev))
 878                 return 0;
 879
 880         utdm = priv->utdm;
 881         ut_info = priv->ut_info;
 882         uf_info = &ut_info->uf_info;
 883         uf_regs = priv->uf_regs;
 884         uccf = priv->uccf;
 885
 886         /* restore gumr guemr */
 887         iowrite8(priv->guemr, &uf_regs->guemr);
 888         iowrite32be(priv->gumr, &uf_regs->gumr);
 889
 890         /* Set Virtual Fifo registers */
 891         iowrite16be(uf_info->urfs, &uf_regs->urfs);
 892         iowrite16be(uf_info->urfet, &uf_regs->urfet);
 893         iowrite16be(uf_info->urfset, &uf_regs->urfset);
 894         iowrite16be(uf_info->utfs, &uf_regs->utfs);
 895         iowrite16be(uf_info->utfet, &uf_regs->utfet);
 896         iowrite16be(uf_info->utftt, &uf_regs->utftt);
 897         /* utfb, urfb are offsets from MURAM base */
 898         iowrite32be(uccf->ucc_fast_tx_virtual_fifo_base_offset, &uf_regs->utfb);
 899         iowrite32be(uccf->ucc_fast_rx_virtual_fifo_base_offset, &uf_regs->urfb);
 900
 901         /* Rx Tx and sync clock routing */
 902         resume_clk_config(priv);
 903
 904         iowrite32be(uf_info->uccm_mask, &uf_regs->uccm);
 905         iowrite32be(0xffffffff, &uf_regs->ucce);
 906
 907         ucc_fast_disable(priv->uccf, COMM_DIR_RX | COMM_DIR_TX);
 908
 909         /* rebuild SIRAM */
 910         if (priv->tsa)
 911                 ucc_tdm_init(priv->utdm, priv->ut_info);
 912
 913         /* Write to QE CECR, UCCx channel to Stop Transmission */
 914         cecr_subblock = ucc_fast_get_qe_cr_subblock(uf_info->ucc_num);
 915         ret = qe_issue_cmd(QE_STOP_TX, cecr_subblock,
 916                            (u8)QE_CR_PROTOCOL_UNSPECIFIED, 0);
 917
 918         /* Set UPSMR normal mode */
 919         iowrite32be(0, &uf_regs->upsmr);
 920
 921         /* init parameter base */
 922         cecr_subblock = ucc_fast_get_qe_cr_subblock(uf_info->ucc_num);
 923         ret = qe_issue_cmd(QE_ASSIGN_PAGE_TO_DEVICE, cecr_subblock,
 924                            QE_CR_PROTOCOL_UNSPECIFIED, priv->ucc_pram_offset);
 925
 926         priv->ucc_pram = (struct ucc_hdlc_param __iomem *)
 927                                 qe_muram_addr(priv->ucc_pram_offset);
 928
 929         /* restore ucc parameter */
 930         memcpy_toio(priv->ucc_pram, priv->ucc_pram_bak,
 931                     sizeof(struct ucc_hdlc_param));
 932         kfree(priv->ucc_pram_bak);
 933
 934         /* rebuild BD entry */
 935         for (i = 0; i < RX_BD_RING_LEN; i++) {
 936                 if (i < (RX_BD_RING_LEN - 1))
 937                         bd_status = R_E_S | R_I_S;
 938                 else
 939                         bd_status = R_E_S | R_I_S | R_W_S;
 940
 941                 iowrite16be(bd_status, &priv->rx_bd_base[i].status);
 942                 iowrite32be(priv->dma_rx_addr + i * MAX_RX_BUF_LENGTH,
 943                             &priv->rx_bd_base[i].buf);
 944         }
 945
 946         for (i = 0; i < TX_BD_RING_LEN; i++) {
 947                 if (i < (TX_BD_RING_LEN - 1))
 948                         bd_status =  T_I_S | T_TC_S;
 949                 else
 950                         bd_status =  T_I_S | T_TC_S | T_W_S;
 951
 952                 iowrite16be(bd_status, &priv->tx_bd_base[i].status);
 953                 iowrite32be(priv->dma_tx_addr + i * MAX_RX_BUF_LENGTH,
 954                             &priv->tx_bd_base[i].buf);
 955         }
 956
 957         /* if hdlc is busy enable TX and RX */
 958         if (priv->hdlc_busy == 1) {
 959                 cecr_subblock = ucc_fast_get_qe_cr_subblock(
 960                                         priv->ut_info->uf_info.ucc_num);
 961
 962                 qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock,
 963                              (u8)QE_CR_PROTOCOL_UNSPECIFIED, 0);
 964
 965                 ucc_fast_enable(priv->uccf, COMM_DIR_RX | COMM_DIR_TX);
 966
 967                 /* Enable the TDM port */
 968                 if (priv->tsa)
 969                         utdm->si_regs->siglmr1_h |= (0x1 << utdm->tdm_port);
 970         }
 971
 972         napi_enable(&priv->napi);
 973         netif_device_attach(priv->ndev);
 974
 975         return 0;
 976 }
 977
 978 static const struct dev_pm_ops uhdlc_pm_ops = {
 979         .suspend = uhdlc_suspend,
 980         .resume = uhdlc_resume,
 981         .freeze = uhdlc_suspend,
 982         .thaw = uhdlc_resume,
 983 };
 984
 985 #define HDLC_PM_OPS (&uhdlc_pm_ops)
 986
 987 #else
 988
 989 #define HDLC_PM_OPS NULL
 990
 991 #endif
 992 static const struct net_device_ops uhdlc_ops = {
 993         .ndo_open       = uhdlc_open,
 994         .ndo_stop       = uhdlc_close,
 995         .ndo_start_xmit = hdlc_start_xmit,
 996         .ndo_do_ioctl   = uhdlc_ioctl,
 997 };
 998
 999 static int ucc_hdlc_probe(struct platform_device *pdev)
1000 {
1001         struct device_node *np = pdev->dev.of_node;
1002         struct ucc_hdlc_private *uhdlc_priv = NULL;
1003         struct ucc_tdm_info *ut_info;
1004         struct ucc_tdm *utdm;
1005         struct resource res;
1006         struct net_device *dev;
1007         hdlc_device *hdlc;
1008         int ucc_num;
1009         const char *sprop;
1010         int ret;
1011         u32 val;
1012
1013         ret = of_property_read_u32_index(np, "cell-index", 0, &val);
1014         if (ret) {
1015                 dev_err(&pdev->dev, "Invalid ucc property\n");
1016                 return -ENODEV;
1017         }
1018
1019         ucc_num = val - 1;
1020         if ((ucc_num > 3) || (ucc_num < 0)) {
1021                 dev_err(&pdev->dev, ": Invalid UCC num\n");
1022                 return -EINVAL;
1023         }
1024
1025         memcpy(&utdm_info[ucc_num], &utdm_primary_info,
1026                sizeof(utdm_primary_info));
1027
1028         ut_info = &utdm_info[ucc_num];
1029         ut_info->uf_info.ucc_num = ucc_num;
1030
1031         sprop = of_get_property(np, "rx-clock-name", NULL);
1032         if (sprop) {
1033                 ut_info->uf_info.rx_clock = qe_clock_source(sprop);
1034                 if ((ut_info->uf_info.rx_clock < QE_CLK_NONE) ||
1035                     (ut_info->uf_info.rx_clock > QE_CLK24)) {
1036                         dev_err(&pdev->dev, "Invalid rx-clock-name property\n");
1037                         return -EINVAL;
1038                 }
1039         } else {
1040                 dev_err(&pdev->dev, "Invalid rx-clock-name property\n");
1041                 return -EINVAL;
1042         }
1043
1044         sprop = of_get_property(np, "tx-clock-name", NULL);
1045         if (sprop) {
1046                 ut_info->uf_info.tx_clock = qe_clock_source(sprop);
1047                 if ((ut_info->uf_info.tx_clock < QE_CLK_NONE) ||
1048                     (ut_info->uf_info.tx_clock > QE_CLK24)) {
1049                         dev_err(&pdev->dev, "Invalid tx-clock-name property\n");
1050                         return -EINVAL;
1051                 }
1052         } else {
1053                 dev_err(&pdev->dev, "Invalid tx-clock-name property\n");
1054                 return -EINVAL;
1055         }
1056
1057         /* use the same clock when work in loopback */
1058         if (ut_info->uf_info.rx_clock == ut_info->uf_info.tx_clock)
1059                 qe_setbrg(ut_info->uf_info.rx_clock, 20000000, 1);
1060
1061         ret = of_address_to_resource(np, 0, &res);
1062         if (ret)
1063                 return -EINVAL;
1064
1065         ut_info->uf_info.regs = res.start;
1066         ut_info->uf_info.irq = irq_of_parse_and_map(np, 0);
1067
1068         uhdlc_priv = kzalloc(sizeof(*uhdlc_priv), GFP_KERNEL);
1069         if (!uhdlc_priv) {
1070                 return -ENOMEM;
1071         }
1072
1073         dev_set_drvdata(&pdev->dev, uhdlc_priv);
1074         uhdlc_priv->dev = &pdev->dev;
1075         uhdlc_priv->ut_info = ut_info;
1076
1077         if (of_get_property(np, "fsl,tdm-interface", NULL))
1078                 uhdlc_priv->tsa = 1;
1079
1080         if (of_get_property(np, "fsl,ucc-internal-loopback", NULL))
1081                 uhdlc_priv->loopback = 1;
1082
1083         if (uhdlc_priv->tsa == 1) {
1084                 utdm = kzalloc(sizeof(*utdm), GFP_KERNEL);
1085                 if (!utdm) {
1086                         ret = -ENOMEM;
1087                         dev_err(&pdev->dev, "No mem to alloc ucc tdm data\n");
1088                         goto free_uhdlc_priv;
1089                 }
1090                 uhdlc_priv->utdm = utdm;
1091                 ret = ucc_of_parse_tdm(np, utdm, ut_info);
1092                 if (ret)
1093                         goto free_utdm;
1094         }
1095
1096         ret = uhdlc_init(uhdlc_priv);
1097         if (ret) {
1098                 dev_err(&pdev->dev, "Failed to init uhdlc\n");
1099                 goto free_utdm;
1100         }
1101
1102         dev = alloc_hdlcdev(uhdlc_priv);
1103         if (!dev) {
1104                 ret = -ENOMEM;
1105                 pr_err("ucc_hdlc: unable to allocate memory\n");
1106                 goto undo_uhdlc_init;
1107         }
1108
1109         uhdlc_priv->ndev = dev;
1110         hdlc = dev_to_hdlc(dev);
1111         dev->tx_queue_len = 16;
1112         dev->netdev_ops = &uhdlc_ops;
1113         hdlc->attach = ucc_hdlc_attach;
1114         hdlc->xmit = ucc_hdlc_tx;
1115         netif_napi_add(dev, &uhdlc_priv->napi, ucc_hdlc_poll, 32);
1116         if (register_hdlc_device(dev)) {
1117                 ret = -ENOBUFS;
1118                 pr_err("ucc_hdlc: unable to register hdlc device\n");
1119                 free_netdev(dev);
1120                 goto free_dev;
1121         }
1122
1123         return 0;
1124
1125 free_dev:
1126         free_netdev(dev);
1127 undo_uhdlc_init:
1128 free_utdm:
1129         if (uhdlc_priv->tsa)
1130                 kfree(utdm);
1131 free_uhdlc_priv:
1132         kfree(uhdlc_priv);
1133         return ret;
1134 }
1135
1136 static int ucc_hdlc_remove(struct platform_device *pdev)
1137 {
1138         struct ucc_hdlc_private *priv = dev_get_drvdata(&pdev->dev);
1139
1140         uhdlc_memclean(priv);
1141
1142         if (priv->utdm->si_regs) {
1143                 iounmap(priv->utdm->si_regs);
1144                 priv->utdm->si_regs = NULL;
1145         }
1146
1147         if (priv->utdm->siram) {
1148                 iounmap(priv->utdm->siram);
1149                 priv->utdm->siram = NULL;
1150         }
1151         kfree(priv);
1152
1153         dev_info(&pdev->dev, "UCC based hdlc module removed\n");
1154
1155         return 0;
1156 }
1157
1158 static const struct of_device_id fsl_ucc_hdlc_of_match[] = {
1159         {
1160         .compatible = "fsl,ucc-hdlc",
1161         },
1162         {},
1163 };
1164
1165 MODULE_DEVICE_TABLE(of, fsl_ucc_hdlc_of_match);
1166
1167 static struct platform_driver ucc_hdlc_driver = {
1168         .probe  = ucc_hdlc_probe,
1169         .remove = ucc_hdlc_remove,
1170         .driver = {
1171                 .name           = DRV_NAME,
1172                 .pm             = HDLC_PM_OPS,
1173                 .of_match_table = fsl_ucc_hdlc_of_match,
1174         },
1175 };
1176
1177 module_platform_driver(ucc_hdlc_driver);
1178 MODULE_LICENSE("GPL");