1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Core driver for the CC770 and AN82527 CAN controllers 4 * 5 * Copyright (C) 2009, 2011 Wolfgang Grandegger <wg@grandegger.com> 6 */ 7 8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 9 10 #include <linux/module.h> 11 #include <linux/init.h> 12 #include <linux/kernel.h> 13 #include <linux/sched.h> 14 #include <linux/types.h> 15 #include <linux/fcntl.h> 16 #include <linux/interrupt.h> 17 #include <linux/ptrace.h> 18 #include <linux/string.h> 19 #include <linux/errno.h> 20 #include <linux/ethtool.h> 21 #include <linux/netdevice.h> 22 #include <linux/if_arp.h> 23 #include <linux/if_ether.h> 24 #include <linux/skbuff.h> 25 #include <linux/delay.h> 26 27 #include <linux/can.h> 28 #include <linux/can/dev.h> 29 #include <linux/can/error.h> 30 #include <linux/can/platform/cc770.h> 31 32 #include "cc770.h" 33 34 MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>"); 35 MODULE_LICENSE("GPL v2"); 36 MODULE_DESCRIPTION(KBUILD_MODNAME "CAN netdevice driver"); 37 38 /* 39 * The CC770 is a CAN controller from Bosch, which is 100% compatible 40 * with the AN82527 from Intel, but with "bugs" being fixed and some 41 * additional functionality, mainly: 42 * 43 * 1. RX and TX error counters are readable. 44 * 2. Support of silent (listen-only) mode. 45 * 3. Message object 15 can receive all types of frames, also RTR and EFF. 46 * 47 * Details are available from Bosch's "CC770_Product_Info_2007-01.pdf", 48 * which explains in detail the compatibility between the CC770 and the 49 * 82527. This driver use the additional functionality 3. on real CC770 50 * devices. Unfortunately, the CC770 does still not store the message 51 * identifier of received remote transmission request frames and 52 * therefore it's set to 0. 53 * 54 * The message objects 1..14 can be used for TX and RX while the message 55 * objects 15 is optimized for RX. It has a shadow register for reliable 56 * data reception under heavy bus load. Therefore it makes sense to use 57 * this message object for the needed use case. The frame type (EFF/SFF) 58 * for the message object 15 can be defined via kernel module parameter 59 * "msgobj15_eff". If not equal 0, it will receive 29-bit EFF frames, 60 * otherwise 11 bit SFF messages. 61 */ 62 static int msgobj15_eff; 63 module_param(msgobj15_eff, int, 0444); 64 MODULE_PARM_DESC(msgobj15_eff, "Extended 29-bit frames for message object 15 " 65 "(default: 11-bit standard frames)"); 66 67 static int i82527_compat; 68 module_param(i82527_compat, int, 0444); 69 MODULE_PARM_DESC(i82527_compat, "Strict Intel 82527 compatibility mode " 70 "without using additional functions"); 71 72 /* 73 * This driver uses the last 5 message objects 11..15. The definitions 74 * and structure below allows to configure and assign them to the real 75 * message object. 76 */ 77 static unsigned char cc770_obj_flags[CC770_OBJ_MAX] = { 78 [CC770_OBJ_RX0] = CC770_OBJ_FLAG_RX, 79 [CC770_OBJ_RX1] = CC770_OBJ_FLAG_RX | CC770_OBJ_FLAG_EFF, 80 [CC770_OBJ_RX_RTR0] = CC770_OBJ_FLAG_RX | CC770_OBJ_FLAG_RTR, 81 [CC770_OBJ_RX_RTR1] = CC770_OBJ_FLAG_RX | CC770_OBJ_FLAG_RTR | 82 CC770_OBJ_FLAG_EFF, 83 [CC770_OBJ_TX] = 0, 84 }; 85 86 static const struct can_bittiming_const cc770_bittiming_const = { 87 .name = KBUILD_MODNAME, 88 .tseg1_min = 1, 89 .tseg1_max = 16, 90 .tseg2_min = 1, 91 .tseg2_max = 8, 92 .sjw_max = 4, 93 .brp_min = 1, 94 .brp_max = 64, 95 .brp_inc = 1, 96 }; 97 98 static inline int intid2obj(unsigned int intid) 99 { 100 if (intid == 2) 101 return 0; 102 else 103 return MSGOBJ_LAST + 2 - intid; 104 } 105 106 static void enable_all_objs(const struct net_device *dev) 107 { 108 struct cc770_priv *priv = netdev_priv(dev); 109 u8 msgcfg; 110 unsigned char obj_flags; 111 unsigned int o, mo; 112 113 for (o = 0; o < ARRAY_SIZE(priv->obj_flags); o++) { 114 obj_flags = priv->obj_flags[o]; 115 mo = obj2msgobj(o); 116 117 if (obj_flags & CC770_OBJ_FLAG_RX) { 118 /* 119 * We don't need extra objects for RTR and EFF if 120 * the additional CC770 functions are enabled. 121 */ 122 if (priv->control_normal_mode & CTRL_EAF) { 123 if (o > 0) 124 continue; 125 netdev_dbg(dev, "Message object %d for " 126 "RX data, RTR, SFF and EFF\n", mo); 127 } else { 128 netdev_dbg(dev, 129 "Message object %d for RX %s %s\n", 130 mo, obj_flags & CC770_OBJ_FLAG_RTR ? 131 "RTR" : "data", 132 obj_flags & CC770_OBJ_FLAG_EFF ? 133 "EFF" : "SFF"); 134 } 135 136 if (obj_flags & CC770_OBJ_FLAG_EFF) 137 msgcfg = MSGCFG_XTD; 138 else 139 msgcfg = 0; 140 if (obj_flags & CC770_OBJ_FLAG_RTR) 141 msgcfg |= MSGCFG_DIR; 142 143 cc770_write_reg(priv, msgobj[mo].config, msgcfg); 144 cc770_write_reg(priv, msgobj[mo].ctrl0, 145 MSGVAL_SET | TXIE_RES | 146 RXIE_SET | INTPND_RES); 147 148 if (obj_flags & CC770_OBJ_FLAG_RTR) 149 cc770_write_reg(priv, msgobj[mo].ctrl1, 150 NEWDAT_RES | CPUUPD_SET | 151 TXRQST_RES | RMTPND_RES); 152 else 153 cc770_write_reg(priv, msgobj[mo].ctrl1, 154 NEWDAT_RES | MSGLST_RES | 155 TXRQST_RES | RMTPND_RES); 156 } else { 157 netdev_dbg(dev, "Message object %d for " 158 "TX data, RTR, SFF and EFF\n", mo); 159 160 cc770_write_reg(priv, msgobj[mo].ctrl1, 161 RMTPND_RES | TXRQST_RES | 162 CPUUPD_RES | NEWDAT_RES); 163 cc770_write_reg(priv, msgobj[mo].ctrl0, 164 MSGVAL_RES | TXIE_RES | 165 RXIE_RES | INTPND_RES); 166 } 167 } 168 } 169 170 static void disable_all_objs(const struct cc770_priv *priv) 171 { 172 int o, mo; 173 174 for (o = 0; o < ARRAY_SIZE(priv->obj_flags); o++) { 175 mo = obj2msgobj(o); 176 177 if (priv->obj_flags[o] & CC770_OBJ_FLAG_RX) { 178 if (o > 0 && priv->control_normal_mode & CTRL_EAF) 179 continue; 180 181 cc770_write_reg(priv, msgobj[mo].ctrl1, 182 NEWDAT_RES | MSGLST_RES | 183 TXRQST_RES | RMTPND_RES); 184 cc770_write_reg(priv, msgobj[mo].ctrl0, 185 MSGVAL_RES | TXIE_RES | 186 RXIE_RES | INTPND_RES); 187 } else { 188 /* Clear message object for send */ 189 cc770_write_reg(priv, msgobj[mo].ctrl1, 190 RMTPND_RES | TXRQST_RES | 191 CPUUPD_RES | NEWDAT_RES); 192 cc770_write_reg(priv, msgobj[mo].ctrl0, 193 MSGVAL_RES | TXIE_RES | 194 RXIE_RES | INTPND_RES); 195 } 196 } 197 } 198 199 static void set_reset_mode(struct net_device *dev) 200 { 201 struct cc770_priv *priv = netdev_priv(dev); 202 203 /* Enable configuration and puts chip in bus-off, disable interrupts */ 204 cc770_write_reg(priv, control, CTRL_CCE | CTRL_INI); 205 206 priv->can.state = CAN_STATE_STOPPED; 207 208 /* Clear interrupts */ 209 cc770_read_reg(priv, interrupt); 210 211 /* Clear status register */ 212 cc770_write_reg(priv, status, 0); 213 214 /* Disable all used message objects */ 215 disable_all_objs(priv); 216 } 217 218 static void set_normal_mode(struct net_device *dev) 219 { 220 struct cc770_priv *priv = netdev_priv(dev); 221 222 /* Clear interrupts */ 223 cc770_read_reg(priv, interrupt); 224 225 /* Clear status register and pre-set last error code */ 226 cc770_write_reg(priv, status, STAT_LEC_MASK); 227 228 /* Enable all used message objects*/ 229 enable_all_objs(dev); 230 231 /* 232 * Clear bus-off, interrupts only for errors, 233 * not for status change 234 */ 235 cc770_write_reg(priv, control, priv->control_normal_mode); 236 237 priv->can.state = CAN_STATE_ERROR_ACTIVE; 238 } 239 240 static void chipset_init(struct cc770_priv *priv) 241 { 242 int mo, id, data; 243 244 /* Enable configuration and put chip in bus-off, disable interrupts */ 245 cc770_write_reg(priv, control, (CTRL_CCE | CTRL_INI)); 246 247 /* Set CLKOUT divider and slew rates */ 248 cc770_write_reg(priv, clkout, priv->clkout); 249 250 /* Configure CPU interface / CLKOUT enable */ 251 cc770_write_reg(priv, cpu_interface, priv->cpu_interface); 252 253 /* Set bus configuration */ 254 cc770_write_reg(priv, bus_config, priv->bus_config); 255 256 /* Clear interrupts */ 257 cc770_read_reg(priv, interrupt); 258 259 /* Clear status register */ 260 cc770_write_reg(priv, status, 0); 261 262 /* Clear and invalidate message objects */ 263 for (mo = MSGOBJ_FIRST; mo <= MSGOBJ_LAST; mo++) { 264 cc770_write_reg(priv, msgobj[mo].ctrl0, 265 INTPND_UNC | RXIE_RES | 266 TXIE_RES | MSGVAL_RES); 267 cc770_write_reg(priv, msgobj[mo].ctrl0, 268 INTPND_RES | RXIE_RES | 269 TXIE_RES | MSGVAL_RES); 270 cc770_write_reg(priv, msgobj[mo].ctrl1, 271 NEWDAT_RES | MSGLST_RES | 272 TXRQST_RES | RMTPND_RES); 273 for (data = 0; data < 8; data++) 274 cc770_write_reg(priv, msgobj[mo].data[data], 0); 275 for (id = 0; id < 4; id++) 276 cc770_write_reg(priv, msgobj[mo].id[id], 0); 277 cc770_write_reg(priv, msgobj[mo].config, 0); 278 } 279 280 /* Set all global ID masks to "don't care" */ 281 cc770_write_reg(priv, global_mask_std[0], 0); 282 cc770_write_reg(priv, global_mask_std[1], 0); 283 cc770_write_reg(priv, global_mask_ext[0], 0); 284 cc770_write_reg(priv, global_mask_ext[1], 0); 285 cc770_write_reg(priv, global_mask_ext[2], 0); 286 cc770_write_reg(priv, global_mask_ext[3], 0); 287 288 } 289 290 static int cc770_probe_chip(struct net_device *dev) 291 { 292 struct cc770_priv *priv = netdev_priv(dev); 293 294 /* Enable configuration, put chip in bus-off, disable ints */ 295 cc770_write_reg(priv, control, CTRL_CCE | CTRL_EAF | CTRL_INI); 296 /* Configure cpu interface / CLKOUT disable */ 297 cc770_write_reg(priv, cpu_interface, priv->cpu_interface); 298 299 /* 300 * Check if hardware reset is still inactive or maybe there 301 * is no chip in this address space 302 */ 303 if (cc770_read_reg(priv, cpu_interface) & CPUIF_RST) { 304 netdev_info(dev, "probing @0x%p failed (reset)\n", 305 priv->reg_base); 306 return -ENODEV; 307 } 308 309 /* Write and read back test pattern (some arbitrary values) */ 310 cc770_write_reg(priv, msgobj[1].data[1], 0x25); 311 cc770_write_reg(priv, msgobj[2].data[3], 0x52); 312 cc770_write_reg(priv, msgobj[10].data[6], 0xc3); 313 if ((cc770_read_reg(priv, msgobj[1].data[1]) != 0x25) || 314 (cc770_read_reg(priv, msgobj[2].data[3]) != 0x52) || 315 (cc770_read_reg(priv, msgobj[10].data[6]) != 0xc3)) { 316 netdev_info(dev, "probing @0x%p failed (pattern)\n", 317 priv->reg_base); 318 return -ENODEV; 319 } 320 321 /* Check if this chip is a CC770 supporting additional functions */ 322 if (cc770_read_reg(priv, control) & CTRL_EAF) 323 priv->control_normal_mode |= CTRL_EAF; 324 325 return 0; 326 } 327 328 static void cc770_start(struct net_device *dev) 329 { 330 struct cc770_priv *priv = netdev_priv(dev); 331 332 /* leave reset mode */ 333 if (priv->can.state != CAN_STATE_STOPPED) 334 set_reset_mode(dev); 335 336 /* leave reset mode */ 337 set_normal_mode(dev); 338 } 339 340 static int cc770_set_mode(struct net_device *dev, enum can_mode mode) 341 { 342 switch (mode) { 343 case CAN_MODE_START: 344 cc770_start(dev); 345 netif_wake_queue(dev); 346 break; 347 348 default: 349 return -EOPNOTSUPP; 350 } 351 352 return 0; 353 } 354 355 static int cc770_set_bittiming(struct net_device *dev) 356 { 357 struct cc770_priv *priv = netdev_priv(dev); 358 struct can_bittiming *bt = &priv->can.bittiming; 359 u8 btr0, btr1; 360 361 btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6); 362 btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) | 363 (((bt->phase_seg2 - 1) & 0x7) << 4); 364 if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES) 365 btr1 |= 0x80; 366 367 netdev_info(dev, "setting BTR0=0x%02x BTR1=0x%02x\n", btr0, btr1); 368 369 cc770_write_reg(priv, bit_timing_0, btr0); 370 cc770_write_reg(priv, bit_timing_1, btr1); 371 372 return 0; 373 } 374 375 static int cc770_get_berr_counter(const struct net_device *dev, 376 struct can_berr_counter *bec) 377 { 378 struct cc770_priv *priv = netdev_priv(dev); 379 380 bec->txerr = cc770_read_reg(priv, tx_error_counter); 381 bec->rxerr = cc770_read_reg(priv, rx_error_counter); 382 383 return 0; 384 } 385 386 static void cc770_tx(struct net_device *dev, int mo) 387 { 388 struct cc770_priv *priv = netdev_priv(dev); 389 struct can_frame *cf = (struct can_frame *)priv->tx_skb->data; 390 u8 dlc, rtr; 391 u32 id; 392 int i; 393 394 dlc = cf->len; 395 id = cf->can_id; 396 rtr = cf->can_id & CAN_RTR_FLAG ? 0 : MSGCFG_DIR; 397 398 cc770_write_reg(priv, msgobj[mo].ctrl0, 399 MSGVAL_RES | TXIE_RES | RXIE_RES | INTPND_RES); 400 cc770_write_reg(priv, msgobj[mo].ctrl1, 401 RMTPND_RES | TXRQST_RES | CPUUPD_SET | NEWDAT_RES); 402 403 if (id & CAN_EFF_FLAG) { 404 id &= CAN_EFF_MASK; 405 cc770_write_reg(priv, msgobj[mo].config, 406 (dlc << 4) | rtr | MSGCFG_XTD); 407 cc770_write_reg(priv, msgobj[mo].id[3], id << 3); 408 cc770_write_reg(priv, msgobj[mo].id[2], id >> 5); 409 cc770_write_reg(priv, msgobj[mo].id[1], id >> 13); 410 cc770_write_reg(priv, msgobj[mo].id[0], id >> 21); 411 } else { 412 id &= CAN_SFF_MASK; 413 cc770_write_reg(priv, msgobj[mo].config, (dlc << 4) | rtr); 414 cc770_write_reg(priv, msgobj[mo].id[0], id >> 3); 415 cc770_write_reg(priv, msgobj[mo].id[1], id << 5); 416 } 417 418 for (i = 0; i < dlc; i++) 419 cc770_write_reg(priv, msgobj[mo].data[i], cf->data[i]); 420 421 cc770_write_reg(priv, msgobj[mo].ctrl1, 422 RMTPND_UNC | TXRQST_SET | CPUUPD_RES | NEWDAT_UNC); 423 cc770_write_reg(priv, msgobj[mo].ctrl0, 424 MSGVAL_SET | TXIE_SET | RXIE_SET | INTPND_UNC); 425 } 426 427 static netdev_tx_t cc770_start_xmit(struct sk_buff *skb, struct net_device *dev) 428 { 429 struct cc770_priv *priv = netdev_priv(dev); 430 unsigned int mo = obj2msgobj(CC770_OBJ_TX); 431 432 if (can_dev_dropped_skb(dev, skb)) 433 return NETDEV_TX_OK; 434 435 netif_stop_queue(dev); 436 437 if ((cc770_read_reg(priv, 438 msgobj[mo].ctrl1) & TXRQST_UNC) == TXRQST_SET) { 439 netdev_err(dev, "TX register is still occupied!\n"); 440 return NETDEV_TX_BUSY; 441 } 442 443 priv->tx_skb = skb; 444 cc770_tx(dev, mo); 445 446 return NETDEV_TX_OK; 447 } 448 449 static void cc770_rx(struct net_device *dev, unsigned int mo, u8 ctrl1) 450 { 451 struct cc770_priv *priv = netdev_priv(dev); 452 struct net_device_stats *stats = &dev->stats; 453 struct can_frame *cf; 454 struct sk_buff *skb; 455 u8 config; 456 u32 id; 457 int i; 458 459 skb = alloc_can_skb(dev, &cf); 460 if (!skb) 461 return; 462 463 config = cc770_read_reg(priv, msgobj[mo].config); 464 465 if (ctrl1 & RMTPND_SET) { 466 /* 467 * Unfortunately, the chip does not store the real message 468 * identifier of the received remote transmission request 469 * frame. Therefore we set it to 0. 470 */ 471 cf->can_id = CAN_RTR_FLAG; 472 if (config & MSGCFG_XTD) 473 cf->can_id |= CAN_EFF_FLAG; 474 cf->len = 0; 475 } else { 476 if (config & MSGCFG_XTD) { 477 id = cc770_read_reg(priv, msgobj[mo].id[3]); 478 id |= cc770_read_reg(priv, msgobj[mo].id[2]) << 8; 479 id |= cc770_read_reg(priv, msgobj[mo].id[1]) << 16; 480 id |= cc770_read_reg(priv, msgobj[mo].id[0]) << 24; 481 id >>= 3; 482 id |= CAN_EFF_FLAG; 483 } else { 484 id = cc770_read_reg(priv, msgobj[mo].id[1]); 485 id |= cc770_read_reg(priv, msgobj[mo].id[0]) << 8; 486 id >>= 5; 487 } 488 489 cf->can_id = id; 490 cf->len = can_cc_dlc2len((config & 0xf0) >> 4); 491 for (i = 0; i < cf->len; i++) 492 cf->data[i] = cc770_read_reg(priv, msgobj[mo].data[i]); 493 494 stats->rx_bytes += cf->len; 495 } 496 stats->rx_packets++; 497 498 netif_rx(skb); 499 } 500 501 static int cc770_err(struct net_device *dev, u8 status) 502 { 503 struct cc770_priv *priv = netdev_priv(dev); 504 struct can_frame *cf; 505 struct sk_buff *skb; 506 u8 lec; 507 508 netdev_dbg(dev, "status interrupt (%#x)\n", status); 509 510 skb = alloc_can_err_skb(dev, &cf); 511 if (!skb) 512 return -ENOMEM; 513 514 /* Use extended functions of the CC770 */ 515 if (priv->control_normal_mode & CTRL_EAF) { 516 cf->can_id |= CAN_ERR_CNT; 517 cf->data[6] = cc770_read_reg(priv, tx_error_counter); 518 cf->data[7] = cc770_read_reg(priv, rx_error_counter); 519 } 520 521 if (status & STAT_BOFF) { 522 /* Disable interrupts */ 523 cc770_write_reg(priv, control, CTRL_INI); 524 cf->can_id |= CAN_ERR_BUSOFF; 525 priv->can.state = CAN_STATE_BUS_OFF; 526 priv->can.can_stats.bus_off++; 527 can_bus_off(dev); 528 } else if (status & STAT_WARN) { 529 cf->can_id |= CAN_ERR_CRTL; 530 /* Only the CC770 does show error passive */ 531 if (cf->data[7] > 127) { 532 cf->data[1] = CAN_ERR_CRTL_RX_PASSIVE | 533 CAN_ERR_CRTL_TX_PASSIVE; 534 priv->can.state = CAN_STATE_ERROR_PASSIVE; 535 priv->can.can_stats.error_passive++; 536 } else { 537 cf->data[1] = CAN_ERR_CRTL_RX_WARNING | 538 CAN_ERR_CRTL_TX_WARNING; 539 priv->can.state = CAN_STATE_ERROR_WARNING; 540 priv->can.can_stats.error_warning++; 541 } 542 } else { 543 /* Back to error active */ 544 cf->can_id |= CAN_ERR_PROT; 545 cf->data[2] = CAN_ERR_PROT_ACTIVE; 546 priv->can.state = CAN_STATE_ERROR_ACTIVE; 547 } 548 549 lec = status & STAT_LEC_MASK; 550 if (lec < 7 && lec > 0) { 551 if (lec == STAT_LEC_ACK) { 552 cf->can_id |= CAN_ERR_ACK; 553 } else { 554 cf->can_id |= CAN_ERR_PROT; 555 switch (lec) { 556 case STAT_LEC_STUFF: 557 cf->data[2] |= CAN_ERR_PROT_STUFF; 558 break; 559 case STAT_LEC_FORM: 560 cf->data[2] |= CAN_ERR_PROT_FORM; 561 break; 562 case STAT_LEC_BIT1: 563 cf->data[2] |= CAN_ERR_PROT_BIT1; 564 break; 565 case STAT_LEC_BIT0: 566 cf->data[2] |= CAN_ERR_PROT_BIT0; 567 break; 568 case STAT_LEC_CRC: 569 cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ; 570 break; 571 } 572 } 573 } 574 575 576 netif_rx(skb); 577 578 return 0; 579 } 580 581 static int cc770_status_interrupt(struct net_device *dev) 582 { 583 struct cc770_priv *priv = netdev_priv(dev); 584 u8 status; 585 586 status = cc770_read_reg(priv, status); 587 /* Reset the status register including RXOK and TXOK */ 588 cc770_write_reg(priv, status, STAT_LEC_MASK); 589 590 if (status & (STAT_WARN | STAT_BOFF) || 591 (status & STAT_LEC_MASK) != STAT_LEC_MASK) { 592 cc770_err(dev, status); 593 return status & STAT_BOFF; 594 } 595 596 return 0; 597 } 598 599 static void cc770_rx_interrupt(struct net_device *dev, unsigned int o) 600 { 601 struct cc770_priv *priv = netdev_priv(dev); 602 struct net_device_stats *stats = &dev->stats; 603 unsigned int mo = obj2msgobj(o); 604 u8 ctrl1; 605 int n = CC770_MAX_MSG; 606 607 while (n--) { 608 ctrl1 = cc770_read_reg(priv, msgobj[mo].ctrl1); 609 610 if (!(ctrl1 & NEWDAT_SET)) { 611 /* Check for RTR if additional functions are enabled */ 612 if (priv->control_normal_mode & CTRL_EAF) { 613 if (!(cc770_read_reg(priv, msgobj[mo].ctrl0) & 614 INTPND_SET)) 615 break; 616 } else { 617 break; 618 } 619 } 620 621 if (ctrl1 & MSGLST_SET) { 622 stats->rx_over_errors++; 623 stats->rx_errors++; 624 } 625 if (mo < MSGOBJ_LAST) 626 cc770_write_reg(priv, msgobj[mo].ctrl1, 627 NEWDAT_RES | MSGLST_RES | 628 TXRQST_UNC | RMTPND_UNC); 629 cc770_rx(dev, mo, ctrl1); 630 631 cc770_write_reg(priv, msgobj[mo].ctrl0, 632 MSGVAL_SET | TXIE_RES | 633 RXIE_SET | INTPND_RES); 634 cc770_write_reg(priv, msgobj[mo].ctrl1, 635 NEWDAT_RES | MSGLST_RES | 636 TXRQST_RES | RMTPND_RES); 637 } 638 } 639 640 static void cc770_rtr_interrupt(struct net_device *dev, unsigned int o) 641 { 642 struct cc770_priv *priv = netdev_priv(dev); 643 unsigned int mo = obj2msgobj(o); 644 u8 ctrl0, ctrl1; 645 int n = CC770_MAX_MSG; 646 647 while (n--) { 648 ctrl0 = cc770_read_reg(priv, msgobj[mo].ctrl0); 649 if (!(ctrl0 & INTPND_SET)) 650 break; 651 652 ctrl1 = cc770_read_reg(priv, msgobj[mo].ctrl1); 653 cc770_rx(dev, mo, ctrl1); 654 655 cc770_write_reg(priv, msgobj[mo].ctrl0, 656 MSGVAL_SET | TXIE_RES | 657 RXIE_SET | INTPND_RES); 658 cc770_write_reg(priv, msgobj[mo].ctrl1, 659 NEWDAT_RES | CPUUPD_SET | 660 TXRQST_RES | RMTPND_RES); 661 } 662 } 663 664 static void cc770_tx_interrupt(struct net_device *dev, unsigned int o) 665 { 666 struct cc770_priv *priv = netdev_priv(dev); 667 struct net_device_stats *stats = &dev->stats; 668 unsigned int mo = obj2msgobj(o); 669 u8 ctrl1; 670 671 ctrl1 = cc770_read_reg(priv, msgobj[mo].ctrl1); 672 673 cc770_write_reg(priv, msgobj[mo].ctrl0, 674 MSGVAL_RES | TXIE_RES | RXIE_RES | INTPND_RES); 675 cc770_write_reg(priv, msgobj[mo].ctrl1, 676 RMTPND_RES | TXRQST_RES | MSGLST_RES | NEWDAT_RES); 677 678 if (unlikely(!priv->tx_skb)) { 679 netdev_err(dev, "missing tx skb in tx interrupt\n"); 680 return; 681 } 682 683 if (unlikely(ctrl1 & MSGLST_SET)) { 684 stats->rx_over_errors++; 685 stats->rx_errors++; 686 } 687 688 /* When the CC770 is sending an RTR message and it receives a regular 689 * message that matches the id of the RTR message, it will overwrite the 690 * outgoing message in the TX register. When this happens we must 691 * process the received message and try to transmit the outgoing skb 692 * again. 693 */ 694 if (unlikely(ctrl1 & NEWDAT_SET)) { 695 cc770_rx(dev, mo, ctrl1); 696 cc770_tx(dev, mo); 697 return; 698 } 699 700 can_put_echo_skb(priv->tx_skb, dev, 0, 0); 701 stats->tx_bytes += can_get_echo_skb(dev, 0, NULL); 702 stats->tx_packets++; 703 priv->tx_skb = NULL; 704 705 netif_wake_queue(dev); 706 } 707 708 static irqreturn_t cc770_interrupt(int irq, void *dev_id) 709 { 710 struct net_device *dev = (struct net_device *)dev_id; 711 struct cc770_priv *priv = netdev_priv(dev); 712 u8 intid; 713 int o, n = 0; 714 715 /* Shared interrupts and IRQ off? */ 716 if (priv->can.state == CAN_STATE_STOPPED) 717 return IRQ_NONE; 718 719 if (priv->pre_irq) 720 priv->pre_irq(priv); 721 722 while (n < CC770_MAX_IRQ) { 723 /* Read the highest pending interrupt request */ 724 intid = cc770_read_reg(priv, interrupt); 725 if (!intid) 726 break; 727 n++; 728 729 if (intid == 1) { 730 /* Exit in case of bus-off */ 731 if (cc770_status_interrupt(dev)) 732 break; 733 } else { 734 o = intid2obj(intid); 735 736 if (o >= CC770_OBJ_MAX) { 737 netdev_err(dev, "Unexpected interrupt id %d\n", 738 intid); 739 continue; 740 } 741 742 if (priv->obj_flags[o] & CC770_OBJ_FLAG_RTR) 743 cc770_rtr_interrupt(dev, o); 744 else if (priv->obj_flags[o] & CC770_OBJ_FLAG_RX) 745 cc770_rx_interrupt(dev, o); 746 else 747 cc770_tx_interrupt(dev, o); 748 } 749 } 750 751 if (priv->post_irq) 752 priv->post_irq(priv); 753 754 if (n >= CC770_MAX_IRQ) 755 netdev_dbg(dev, "%d messages handled in ISR", n); 756 757 return (n) ? IRQ_HANDLED : IRQ_NONE; 758 } 759 760 static int cc770_open(struct net_device *dev) 761 { 762 struct cc770_priv *priv = netdev_priv(dev); 763 int err; 764 765 /* set chip into reset mode */ 766 set_reset_mode(dev); 767 768 /* common open */ 769 err = open_candev(dev); 770 if (err) 771 return err; 772 773 err = request_irq(dev->irq, &cc770_interrupt, priv->irq_flags, 774 dev->name, dev); 775 if (err) { 776 close_candev(dev); 777 return -EAGAIN; 778 } 779 780 /* init and start chip */ 781 cc770_start(dev); 782 783 netif_start_queue(dev); 784 785 return 0; 786 } 787 788 static int cc770_close(struct net_device *dev) 789 { 790 netif_stop_queue(dev); 791 set_reset_mode(dev); 792 793 free_irq(dev->irq, dev); 794 close_candev(dev); 795 796 return 0; 797 } 798 799 struct net_device *alloc_cc770dev(int sizeof_priv) 800 { 801 struct net_device *dev; 802 struct cc770_priv *priv; 803 804 dev = alloc_candev(sizeof(struct cc770_priv) + sizeof_priv, 805 CC770_ECHO_SKB_MAX); 806 if (!dev) 807 return NULL; 808 809 priv = netdev_priv(dev); 810 811 priv->dev = dev; 812 priv->can.bittiming_const = &cc770_bittiming_const; 813 priv->can.do_set_bittiming = cc770_set_bittiming; 814 priv->can.do_set_mode = cc770_set_mode; 815 priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES; 816 priv->tx_skb = NULL; 817 818 memcpy(priv->obj_flags, cc770_obj_flags, sizeof(cc770_obj_flags)); 819 820 if (sizeof_priv) 821 priv->priv = (void *)priv + sizeof(struct cc770_priv); 822 823 return dev; 824 } 825 EXPORT_SYMBOL_GPL(alloc_cc770dev); 826 827 void free_cc770dev(struct net_device *dev) 828 { 829 free_candev(dev); 830 } 831 EXPORT_SYMBOL_GPL(free_cc770dev); 832 833 static const struct net_device_ops cc770_netdev_ops = { 834 .ndo_open = cc770_open, 835 .ndo_stop = cc770_close, 836 .ndo_start_xmit = cc770_start_xmit, 837 .ndo_change_mtu = can_change_mtu, 838 }; 839 840 static const struct ethtool_ops cc770_ethtool_ops = { 841 .get_ts_info = ethtool_op_get_ts_info, 842 }; 843 844 int register_cc770dev(struct net_device *dev) 845 { 846 struct cc770_priv *priv = netdev_priv(dev); 847 int err; 848 849 err = cc770_probe_chip(dev); 850 if (err) 851 return err; 852 853 dev->netdev_ops = &cc770_netdev_ops; 854 dev->ethtool_ops = &cc770_ethtool_ops; 855 856 dev->flags |= IFF_ECHO; /* we support local echo */ 857 858 /* Should we use additional functions? */ 859 if (!i82527_compat && priv->control_normal_mode & CTRL_EAF) { 860 priv->can.do_get_berr_counter = cc770_get_berr_counter; 861 priv->control_normal_mode = CTRL_IE | CTRL_EAF | CTRL_EIE; 862 netdev_dbg(dev, "i82527 mode with additional functions\n"); 863 } else { 864 priv->control_normal_mode = CTRL_IE | CTRL_EIE; 865 netdev_dbg(dev, "strict i82527 compatibility mode\n"); 866 } 867 868 chipset_init(priv); 869 set_reset_mode(dev); 870 871 return register_candev(dev); 872 } 873 EXPORT_SYMBOL_GPL(register_cc770dev); 874 875 void unregister_cc770dev(struct net_device *dev) 876 { 877 set_reset_mode(dev); 878 unregister_candev(dev); 879 } 880 EXPORT_SYMBOL_GPL(unregister_cc770dev); 881 882 static __init int cc770_init(void) 883 { 884 if (msgobj15_eff) { 885 cc770_obj_flags[CC770_OBJ_RX0] |= CC770_OBJ_FLAG_EFF; 886 cc770_obj_flags[CC770_OBJ_RX1] &= ~CC770_OBJ_FLAG_EFF; 887 } 888 889 pr_info("CAN netdevice driver\n"); 890 891 return 0; 892 } 893 module_init(cc770_init); 894 895 static __exit void cc770_exit(void) 896 { 897 pr_info("driver removed\n"); 898 } 899 module_exit(cc770_exit); 900