cc770.c revision 7bb4db93ae59e0faf810a83a8578f56bc968ab01
1/* 2 * Core driver for the CC770 and AN82527 CAN controllers 3 * 4 * Copyright (C) 2009, 2011 Wolfgang Grandegger <wg@grandegger.com> 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the version 2 of the GNU General Public License 8 * as published by the Free Software Foundation 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 */ 15 16#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 17 18#include <linux/module.h> 19#include <linux/init.h> 20#include <linux/kernel.h> 21#include <linux/sched.h> 22#include <linux/types.h> 23#include <linux/fcntl.h> 24#include <linux/interrupt.h> 25#include <linux/ptrace.h> 26#include <linux/string.h> 27#include <linux/errno.h> 28#include <linux/netdevice.h> 29#include <linux/if_arp.h> 30#include <linux/if_ether.h> 31#include <linux/skbuff.h> 32#include <linux/delay.h> 33 34#include <linux/can.h> 35#include <linux/can/dev.h> 36#include <linux/can/error.h> 37#include <linux/can/dev.h> 38#include <linux/can/platform/cc770.h> 39 40#include "cc770.h" 41 42MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>"); 43MODULE_LICENSE("GPL v2"); 44MODULE_DESCRIPTION(KBUILD_MODNAME "CAN netdevice driver"); 45 46/* 47 * The CC770 is a CAN controller from Bosch, which is 100% compatible 48 * with the AN82527 from Intel, but with "bugs" being fixed and some 49 * additional functionality, mainly: 50 * 51 * 1. RX and TX error counters are readable. 52 * 2. Support of silent (listen-only) mode. 53 * 3. Message object 15 can receive all types of frames, also RTR and EFF. 54 * 55 * Details are available from Bosch's "CC770_Product_Info_2007-01.pdf", 56 * which explains in detail the compatibility between the CC770 and the 57 * 82527. This driver use the additional functionality 3. on real CC770 58 * devices. Unfortunately, the CC770 does still not store the message 59 * identifier of received remote transmission request frames and 60 * therefore it's set to 0. 61 * 62 * The message objects 1..14 can be used for TX and RX while the message 63 * objects 15 is optimized for RX. It has a shadow register for reliable 64 * data receiption under heavy bus load. Therefore it makes sense to use 65 * this message object for the needed use case. The frame type (EFF/SFF) 66 * for the message object 15 can be defined via kernel module parameter 67 * "msgobj15_eff". If not equal 0, it will receive 29-bit EFF frames, 68 * otherwise 11 bit SFF messages. 69 */ 70static int msgobj15_eff; 71module_param(msgobj15_eff, int, S_IRUGO); 72MODULE_PARM_DESC(msgobj15_eff, "Extended 29-bit frames for message object 15 " 73 "(default: 11-bit standard frames)"); 74 75static int i82527_compat; 76module_param(i82527_compat, int, S_IRUGO); 77MODULE_PARM_DESC(i82527_compat, "Strict Intel 82527 comptibility mode " 78 "without using additional functions"); 79 80/* 81 * This driver uses the last 5 message objects 11..15. The definitions 82 * and structure below allows to configure and assign them to the real 83 * message object. 84 */ 85static unsigned char cc770_obj_flags[CC770_OBJ_MAX] = { 86 [CC770_OBJ_RX0] = CC770_OBJ_FLAG_RX, 87 [CC770_OBJ_RX1] = CC770_OBJ_FLAG_RX | CC770_OBJ_FLAG_EFF, 88 [CC770_OBJ_RX_RTR0] = CC770_OBJ_FLAG_RX | CC770_OBJ_FLAG_RTR, 89 [CC770_OBJ_RX_RTR1] = CC770_OBJ_FLAG_RX | CC770_OBJ_FLAG_RTR | 90 CC770_OBJ_FLAG_EFF, 91 [CC770_OBJ_TX] = 0, 92}; 93 94static struct can_bittiming_const cc770_bittiming_const = { 95 .name = KBUILD_MODNAME, 96 .tseg1_min = 1, 97 .tseg1_max = 16, 98 .tseg2_min = 1, 99 .tseg2_max = 8, 100 .sjw_max = 4, 101 .brp_min = 1, 102 .brp_max = 64, 103 .brp_inc = 1, 104}; 105 106static inline int intid2obj(unsigned int intid) 107{ 108 if (intid == 2) 109 return 0; 110 else 111 return MSGOBJ_LAST + 2 - intid; 112} 113 114static void enable_all_objs(const struct net_device *dev) 115{ 116 struct cc770_priv *priv = netdev_priv(dev); 117 u8 msgcfg; 118 unsigned char obj_flags; 119 unsigned int o, mo; 120 121 for (o = 0; o < ARRAY_SIZE(priv->obj_flags); o++) { 122 obj_flags = priv->obj_flags[o]; 123 mo = obj2msgobj(o); 124 125 if (obj_flags & CC770_OBJ_FLAG_RX) { 126 /* 127 * We don't need extra objects for RTR and EFF if 128 * the additional CC770 functions are enabled. 129 */ 130 if (priv->control_normal_mode & CTRL_EAF) { 131 if (o > 0) 132 continue; 133 netdev_dbg(dev, "Message object %d for " 134 "RX data, RTR, SFF and EFF\n", mo); 135 } else { 136 netdev_dbg(dev, 137 "Message object %d for RX %s %s\n", 138 mo, obj_flags & CC770_OBJ_FLAG_RTR ? 139 "RTR" : "data", 140 obj_flags & CC770_OBJ_FLAG_EFF ? 141 "EFF" : "SFF"); 142 } 143 144 if (obj_flags & CC770_OBJ_FLAG_EFF) 145 msgcfg = MSGCFG_XTD; 146 else 147 msgcfg = 0; 148 if (obj_flags & CC770_OBJ_FLAG_RTR) 149 msgcfg |= MSGCFG_DIR; 150 151 cc770_write_reg(priv, msgobj[mo].config, msgcfg); 152 cc770_write_reg(priv, msgobj[mo].ctrl0, 153 MSGVAL_SET | TXIE_RES | 154 RXIE_SET | INTPND_RES); 155 156 if (obj_flags & CC770_OBJ_FLAG_RTR) 157 cc770_write_reg(priv, msgobj[mo].ctrl1, 158 NEWDAT_RES | CPUUPD_SET | 159 TXRQST_RES | RMTPND_RES); 160 else 161 cc770_write_reg(priv, msgobj[mo].ctrl1, 162 NEWDAT_RES | MSGLST_RES | 163 TXRQST_RES | RMTPND_RES); 164 } else { 165 netdev_dbg(dev, "Message object %d for " 166 "TX data, RTR, SFF and EFF\n", mo); 167 168 cc770_write_reg(priv, msgobj[mo].ctrl1, 169 RMTPND_RES | TXRQST_RES | 170 CPUUPD_RES | NEWDAT_RES); 171 cc770_write_reg(priv, msgobj[mo].ctrl0, 172 MSGVAL_RES | TXIE_RES | 173 RXIE_RES | INTPND_RES); 174 } 175 } 176} 177 178static void disable_all_objs(const struct cc770_priv *priv) 179{ 180 int o, mo; 181 182 for (o = 0; o < ARRAY_SIZE(priv->obj_flags); o++) { 183 mo = obj2msgobj(o); 184 185 if (priv->obj_flags[o] & CC770_OBJ_FLAG_RX) { 186 if (o > 0 && priv->control_normal_mode & CTRL_EAF) 187 continue; 188 189 cc770_write_reg(priv, msgobj[mo].ctrl1, 190 NEWDAT_RES | MSGLST_RES | 191 TXRQST_RES | RMTPND_RES); 192 cc770_write_reg(priv, msgobj[mo].ctrl0, 193 MSGVAL_RES | TXIE_RES | 194 RXIE_RES | INTPND_RES); 195 } else { 196 /* Clear message object for send */ 197 cc770_write_reg(priv, msgobj[mo].ctrl1, 198 RMTPND_RES | TXRQST_RES | 199 CPUUPD_RES | NEWDAT_RES); 200 cc770_write_reg(priv, msgobj[mo].ctrl0, 201 MSGVAL_RES | TXIE_RES | 202 RXIE_RES | INTPND_RES); 203 } 204 } 205} 206 207static void set_reset_mode(struct net_device *dev) 208{ 209 struct cc770_priv *priv = netdev_priv(dev); 210 211 /* Enable configuration and puts chip in bus-off, disable interrupts */ 212 cc770_write_reg(priv, control, CTRL_CCE | CTRL_INI); 213 214 priv->can.state = CAN_STATE_STOPPED; 215 216 /* Clear interrupts */ 217 cc770_read_reg(priv, interrupt); 218 219 /* Clear status register */ 220 cc770_write_reg(priv, status, 0); 221 222 /* Disable all used message objects */ 223 disable_all_objs(priv); 224} 225 226static void set_normal_mode(struct net_device *dev) 227{ 228 struct cc770_priv *priv = netdev_priv(dev); 229 230 /* Clear interrupts */ 231 cc770_read_reg(priv, interrupt); 232 233 /* Clear status register and pre-set last error code */ 234 cc770_write_reg(priv, status, STAT_LEC_MASK); 235 236 /* Enable all used message objects*/ 237 enable_all_objs(dev); 238 239 /* 240 * Clear bus-off, interrupts only for errors, 241 * not for status change 242 */ 243 cc770_write_reg(priv, control, priv->control_normal_mode); 244 245 priv->can.state = CAN_STATE_ERROR_ACTIVE; 246} 247 248static void chipset_init(struct cc770_priv *priv) 249{ 250 int mo, id, data; 251 252 /* Enable configuration and put chip in bus-off, disable interrupts */ 253 cc770_write_reg(priv, control, (CTRL_CCE | CTRL_INI)); 254 255 /* Set CLKOUT divider and slew rates */ 256 cc770_write_reg(priv, clkout, priv->clkout); 257 258 /* Configure CPU interface / CLKOUT enable */ 259 cc770_write_reg(priv, cpu_interface, priv->cpu_interface); 260 261 /* Set bus configuration */ 262 cc770_write_reg(priv, bus_config, priv->bus_config); 263 264 /* Clear interrupts */ 265 cc770_read_reg(priv, interrupt); 266 267 /* Clear status register */ 268 cc770_write_reg(priv, status, 0); 269 270 /* Clear and invalidate message objects */ 271 for (mo = MSGOBJ_FIRST; mo <= MSGOBJ_LAST; mo++) { 272 cc770_write_reg(priv, msgobj[mo].ctrl0, 273 INTPND_UNC | RXIE_RES | 274 TXIE_RES | MSGVAL_RES); 275 cc770_write_reg(priv, msgobj[mo].ctrl0, 276 INTPND_RES | RXIE_RES | 277 TXIE_RES | MSGVAL_RES); 278 cc770_write_reg(priv, msgobj[mo].ctrl1, 279 NEWDAT_RES | MSGLST_RES | 280 TXRQST_RES | RMTPND_RES); 281 for (data = 0; data < 8; data++) 282 cc770_write_reg(priv, msgobj[mo].data[data], 0); 283 for (id = 0; id < 4; id++) 284 cc770_write_reg(priv, msgobj[mo].id[id], 0); 285 cc770_write_reg(priv, msgobj[mo].config, 0); 286 } 287 288 /* Set all global ID masks to "don't care" */ 289 cc770_write_reg(priv, global_mask_std[0], 0); 290 cc770_write_reg(priv, global_mask_std[1], 0); 291 cc770_write_reg(priv, global_mask_ext[0], 0); 292 cc770_write_reg(priv, global_mask_ext[1], 0); 293 cc770_write_reg(priv, global_mask_ext[2], 0); 294 cc770_write_reg(priv, global_mask_ext[3], 0); 295 296} 297 298static int cc770_probe_chip(struct net_device *dev) 299{ 300 struct cc770_priv *priv = netdev_priv(dev); 301 302 /* Enable configuration, put chip in bus-off, disable ints */ 303 cc770_write_reg(priv, control, CTRL_CCE | CTRL_EAF | CTRL_INI); 304 /* Configure cpu interface / CLKOUT disable */ 305 cc770_write_reg(priv, cpu_interface, priv->cpu_interface); 306 307 /* 308 * Check if hardware reset is still inactive or maybe there 309 * is no chip in this address space 310 */ 311 if (cc770_read_reg(priv, cpu_interface) & CPUIF_RST) { 312 netdev_info(dev, "probing @0x%p failed (reset)\n", 313 priv->reg_base); 314 return -ENODEV; 315 } 316 317 /* Write and read back test pattern (some arbitrary values) */ 318 cc770_write_reg(priv, msgobj[1].data[1], 0x25); 319 cc770_write_reg(priv, msgobj[2].data[3], 0x52); 320 cc770_write_reg(priv, msgobj[10].data[6], 0xc3); 321 if ((cc770_read_reg(priv, msgobj[1].data[1]) != 0x25) || 322 (cc770_read_reg(priv, msgobj[2].data[3]) != 0x52) || 323 (cc770_read_reg(priv, msgobj[10].data[6]) != 0xc3)) { 324 netdev_info(dev, "probing @0x%p failed (pattern)\n", 325 priv->reg_base); 326 return -ENODEV; 327 } 328 329 /* Check if this chip is a CC770 supporting additional functions */ 330 if (cc770_read_reg(priv, control) & CTRL_EAF) 331 priv->control_normal_mode |= CTRL_EAF; 332 333 return 0; 334} 335 336static void cc770_start(struct net_device *dev) 337{ 338 struct cc770_priv *priv = netdev_priv(dev); 339 340 /* leave reset mode */ 341 if (priv->can.state != CAN_STATE_STOPPED) 342 set_reset_mode(dev); 343 344 /* leave reset mode */ 345 set_normal_mode(dev); 346} 347 348static int cc770_set_mode(struct net_device *dev, enum can_mode mode) 349{ 350 switch (mode) { 351 case CAN_MODE_START: 352 cc770_start(dev); 353 netif_wake_queue(dev); 354 break; 355 356 default: 357 return -EOPNOTSUPP; 358 } 359 360 return 0; 361} 362 363static int cc770_set_bittiming(struct net_device *dev) 364{ 365 struct cc770_priv *priv = netdev_priv(dev); 366 struct can_bittiming *bt = &priv->can.bittiming; 367 u8 btr0, btr1; 368 369 btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6); 370 btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) | 371 (((bt->phase_seg2 - 1) & 0x7) << 4); 372 if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES) 373 btr1 |= 0x80; 374 375 netdev_info(dev, "setting BTR0=0x%02x BTR1=0x%02x\n", btr0, btr1); 376 377 cc770_write_reg(priv, bit_timing_0, btr0); 378 cc770_write_reg(priv, bit_timing_1, btr1); 379 380 return 0; 381} 382 383static int cc770_get_berr_counter(const struct net_device *dev, 384 struct can_berr_counter *bec) 385{ 386 struct cc770_priv *priv = netdev_priv(dev); 387 388 bec->txerr = cc770_read_reg(priv, tx_error_counter); 389 bec->rxerr = cc770_read_reg(priv, rx_error_counter); 390 391 return 0; 392} 393 394static netdev_tx_t cc770_start_xmit(struct sk_buff *skb, struct net_device *dev) 395{ 396 struct cc770_priv *priv = netdev_priv(dev); 397 struct net_device_stats *stats = &dev->stats; 398 struct can_frame *cf = (struct can_frame *)skb->data; 399 unsigned int mo = obj2msgobj(CC770_OBJ_TX); 400 u8 dlc, rtr; 401 u32 id; 402 int i; 403 404 if (can_dropped_invalid_skb(dev, skb)) 405 return NETDEV_TX_OK; 406 407 if ((cc770_read_reg(priv, 408 msgobj[mo].ctrl1) & TXRQST_UNC) == TXRQST_SET) { 409 netdev_err(dev, "TX register is still occupied!\n"); 410 return NETDEV_TX_BUSY; 411 } 412 413 netif_stop_queue(dev); 414 415 dlc = cf->can_dlc; 416 id = cf->can_id; 417 if (cf->can_id & CAN_RTR_FLAG) 418 rtr = 0; 419 else 420 rtr = MSGCFG_DIR; 421 cc770_write_reg(priv, msgobj[mo].ctrl1, 422 RMTPND_RES | TXRQST_RES | CPUUPD_SET | NEWDAT_RES); 423 cc770_write_reg(priv, msgobj[mo].ctrl0, 424 MSGVAL_SET | TXIE_SET | RXIE_RES | INTPND_RES); 425 if (id & CAN_EFF_FLAG) { 426 id &= CAN_EFF_MASK; 427 cc770_write_reg(priv, msgobj[mo].config, 428 (dlc << 4) | rtr | MSGCFG_XTD); 429 cc770_write_reg(priv, msgobj[mo].id[3], id << 3); 430 cc770_write_reg(priv, msgobj[mo].id[2], id >> 5); 431 cc770_write_reg(priv, msgobj[mo].id[1], id >> 13); 432 cc770_write_reg(priv, msgobj[mo].id[0], id >> 21); 433 } else { 434 id &= CAN_SFF_MASK; 435 cc770_write_reg(priv, msgobj[mo].config, (dlc << 4) | rtr); 436 cc770_write_reg(priv, msgobj[mo].id[0], id >> 3); 437 cc770_write_reg(priv, msgobj[mo].id[1], id << 5); 438 } 439 440 for (i = 0; i < dlc; i++) 441 cc770_write_reg(priv, msgobj[mo].data[i], cf->data[i]); 442 443 /* Store echo skb before starting the transfer */ 444 can_put_echo_skb(skb, dev, 0); 445 446 cc770_write_reg(priv, msgobj[mo].ctrl1, 447 RMTPND_RES | TXRQST_SET | CPUUPD_RES | NEWDAT_UNC); 448 449 stats->tx_bytes += dlc; 450 451 452 /* 453 * HM: We had some cases of repeated IRQs so make sure the 454 * INT is acknowledged I know it's already further up, but 455 * doing again fixed the issue 456 */ 457 cc770_write_reg(priv, msgobj[mo].ctrl0, 458 MSGVAL_UNC | TXIE_UNC | RXIE_UNC | INTPND_RES); 459 460 return NETDEV_TX_OK; 461} 462 463static void cc770_rx(struct net_device *dev, unsigned int mo, u8 ctrl1) 464{ 465 struct cc770_priv *priv = netdev_priv(dev); 466 struct net_device_stats *stats = &dev->stats; 467 struct can_frame *cf; 468 struct sk_buff *skb; 469 u8 config; 470 u32 id; 471 int i; 472 473 skb = alloc_can_skb(dev, &cf); 474 if (!skb) 475 return; 476 477 config = cc770_read_reg(priv, msgobj[mo].config); 478 479 if (ctrl1 & RMTPND_SET) { 480 /* 481 * Unfortunately, the chip does not store the real message 482 * identifier of the received remote transmission request 483 * frame. Therefore we set it to 0. 484 */ 485 cf->can_id = CAN_RTR_FLAG; 486 if (config & MSGCFG_XTD) 487 cf->can_id |= CAN_EFF_FLAG; 488 cf->can_dlc = 0; 489 } else { 490 if (config & MSGCFG_XTD) { 491 id = cc770_read_reg(priv, msgobj[mo].id[3]); 492 id |= cc770_read_reg(priv, msgobj[mo].id[2]) << 8; 493 id |= cc770_read_reg(priv, msgobj[mo].id[1]) << 16; 494 id |= cc770_read_reg(priv, msgobj[mo].id[0]) << 24; 495 id >>= 3; 496 id |= CAN_EFF_FLAG; 497 } else { 498 id = cc770_read_reg(priv, msgobj[mo].id[1]); 499 id |= cc770_read_reg(priv, msgobj[mo].id[0]) << 8; 500 id >>= 5; 501 } 502 503 cf->can_id = id; 504 cf->can_dlc = get_can_dlc((config & 0xf0) >> 4); 505 for (i = 0; i < cf->can_dlc; i++) 506 cf->data[i] = cc770_read_reg(priv, msgobj[mo].data[i]); 507 } 508 netif_rx(skb); 509 510 stats->rx_packets++; 511 stats->rx_bytes += cf->can_dlc; 512} 513 514static int cc770_err(struct net_device *dev, u8 status) 515{ 516 struct cc770_priv *priv = netdev_priv(dev); 517 struct net_device_stats *stats = &dev->stats; 518 struct can_frame *cf; 519 struct sk_buff *skb; 520 u8 lec; 521 522 netdev_dbg(dev, "status interrupt (%#x)\n", status); 523 524 skb = alloc_can_err_skb(dev, &cf); 525 if (!skb) 526 return -ENOMEM; 527 528 /* Use extended functions of the CC770 */ 529 if (priv->control_normal_mode & CTRL_EAF) { 530 cf->data[6] = cc770_read_reg(priv, tx_error_counter); 531 cf->data[7] = cc770_read_reg(priv, rx_error_counter); 532 } 533 534 if (status & STAT_BOFF) { 535 /* Disable interrupts */ 536 cc770_write_reg(priv, control, CTRL_INI); 537 cf->can_id |= CAN_ERR_BUSOFF; 538 priv->can.state = CAN_STATE_BUS_OFF; 539 can_bus_off(dev); 540 } else if (status & STAT_WARN) { 541 cf->can_id |= CAN_ERR_CRTL; 542 /* Only the CC770 does show error passive */ 543 if (cf->data[7] > 127) { 544 cf->data[1] = CAN_ERR_CRTL_RX_PASSIVE | 545 CAN_ERR_CRTL_TX_PASSIVE; 546 priv->can.state = CAN_STATE_ERROR_PASSIVE; 547 priv->can.can_stats.error_passive++; 548 } else { 549 cf->data[1] = CAN_ERR_CRTL_RX_WARNING | 550 CAN_ERR_CRTL_TX_WARNING; 551 priv->can.state = CAN_STATE_ERROR_WARNING; 552 priv->can.can_stats.error_warning++; 553 } 554 } else { 555 /* Back to error avtive */ 556 cf->can_id |= CAN_ERR_PROT; 557 cf->data[2] = CAN_ERR_PROT_ACTIVE; 558 priv->can.state = CAN_STATE_ERROR_ACTIVE; 559 } 560 561 lec = status & STAT_LEC_MASK; 562 if (lec < 7 && lec > 0) { 563 if (lec == STAT_LEC_ACK) { 564 cf->can_id |= CAN_ERR_ACK; 565 } else { 566 cf->can_id |= CAN_ERR_PROT; 567 switch (lec) { 568 case STAT_LEC_STUFF: 569 cf->data[2] |= CAN_ERR_PROT_STUFF; 570 break; 571 case STAT_LEC_FORM: 572 cf->data[2] |= CAN_ERR_PROT_FORM; 573 break; 574 case STAT_LEC_BIT1: 575 cf->data[2] |= CAN_ERR_PROT_BIT1; 576 break; 577 case STAT_LEC_BIT0: 578 cf->data[2] |= CAN_ERR_PROT_BIT0; 579 break; 580 case STAT_LEC_CRC: 581 cf->data[3] |= CAN_ERR_PROT_LOC_CRC_SEQ; 582 break; 583 } 584 } 585 } 586 587 netif_rx(skb); 588 589 stats->rx_packets++; 590 stats->rx_bytes += cf->can_dlc; 591 592 return 0; 593} 594 595static int cc770_status_interrupt(struct net_device *dev) 596{ 597 struct cc770_priv *priv = netdev_priv(dev); 598 u8 status; 599 600 status = cc770_read_reg(priv, status); 601 /* Reset the status register including RXOK and TXOK */ 602 cc770_write_reg(priv, status, STAT_LEC_MASK); 603 604 if (status & (STAT_WARN | STAT_BOFF) || 605 (status & STAT_LEC_MASK) != STAT_LEC_MASK) { 606 cc770_err(dev, status); 607 return status & STAT_BOFF; 608 } 609 610 return 0; 611} 612 613static void cc770_rx_interrupt(struct net_device *dev, unsigned int o) 614{ 615 struct cc770_priv *priv = netdev_priv(dev); 616 struct net_device_stats *stats = &dev->stats; 617 unsigned int mo = obj2msgobj(o); 618 u8 ctrl1; 619 int n = CC770_MAX_MSG; 620 621 while (n--) { 622 ctrl1 = cc770_read_reg(priv, msgobj[mo].ctrl1); 623 624 if (!(ctrl1 & NEWDAT_SET)) { 625 /* Check for RTR if additional functions are enabled */ 626 if (priv->control_normal_mode & CTRL_EAF) { 627 if (!(cc770_read_reg(priv, msgobj[mo].ctrl0) & 628 INTPND_SET)) 629 break; 630 } else { 631 break; 632 } 633 } 634 635 if (ctrl1 & MSGLST_SET) { 636 stats->rx_over_errors++; 637 stats->rx_errors++; 638 } 639 if (mo < MSGOBJ_LAST) 640 cc770_write_reg(priv, msgobj[mo].ctrl1, 641 NEWDAT_RES | MSGLST_RES | 642 TXRQST_UNC | RMTPND_UNC); 643 cc770_rx(dev, mo, ctrl1); 644 645 cc770_write_reg(priv, msgobj[mo].ctrl0, 646 MSGVAL_SET | TXIE_RES | 647 RXIE_SET | INTPND_RES); 648 cc770_write_reg(priv, msgobj[mo].ctrl1, 649 NEWDAT_RES | MSGLST_RES | 650 TXRQST_RES | RMTPND_RES); 651 } 652} 653 654static void cc770_rtr_interrupt(struct net_device *dev, unsigned int o) 655{ 656 struct cc770_priv *priv = netdev_priv(dev); 657 unsigned int mo = obj2msgobj(o); 658 u8 ctrl0, ctrl1; 659 int n = CC770_MAX_MSG; 660 661 while (n--) { 662 ctrl0 = cc770_read_reg(priv, msgobj[mo].ctrl0); 663 if (!(ctrl0 & INTPND_SET)) 664 break; 665 666 ctrl1 = cc770_read_reg(priv, msgobj[mo].ctrl1); 667 cc770_rx(dev, mo, ctrl1); 668 669 cc770_write_reg(priv, msgobj[mo].ctrl0, 670 MSGVAL_SET | TXIE_RES | 671 RXIE_SET | INTPND_RES); 672 cc770_write_reg(priv, msgobj[mo].ctrl1, 673 NEWDAT_RES | CPUUPD_SET | 674 TXRQST_RES | RMTPND_RES); 675 } 676} 677 678static void cc770_tx_interrupt(struct net_device *dev, unsigned int o) 679{ 680 struct cc770_priv *priv = netdev_priv(dev); 681 struct net_device_stats *stats = &dev->stats; 682 unsigned int mo = obj2msgobj(o); 683 684 /* Nothing more to send, switch off interrupts */ 685 cc770_write_reg(priv, msgobj[mo].ctrl0, 686 MSGVAL_RES | TXIE_RES | RXIE_RES | INTPND_RES); 687 /* 688 * We had some cases of repeated IRQ so make sure the 689 * INT is acknowledged 690 */ 691 cc770_write_reg(priv, msgobj[mo].ctrl0, 692 MSGVAL_UNC | TXIE_UNC | RXIE_UNC | INTPND_RES); 693 694 stats->tx_packets++; 695 can_get_echo_skb(dev, 0); 696 netif_wake_queue(dev); 697} 698 699irqreturn_t cc770_interrupt(int irq, void *dev_id) 700{ 701 struct net_device *dev = (struct net_device *)dev_id; 702 struct cc770_priv *priv = netdev_priv(dev); 703 u8 intid; 704 int o, n = 0; 705 706 /* Shared interrupts and IRQ off? */ 707 if (priv->can.state == CAN_STATE_STOPPED) 708 return IRQ_NONE; 709 710 if (priv->pre_irq) 711 priv->pre_irq(priv); 712 713 while (n < CC770_MAX_IRQ) { 714 /* Read the highest pending interrupt request */ 715 intid = cc770_read_reg(priv, interrupt); 716 if (!intid) 717 break; 718 n++; 719 720 if (intid == 1) { 721 /* Exit in case of bus-off */ 722 if (cc770_status_interrupt(dev)) 723 break; 724 } else { 725 o = intid2obj(intid); 726 727 if (o >= CC770_OBJ_MAX) { 728 netdev_err(dev, "Unexpected interrupt id %d\n", 729 intid); 730 continue; 731 } 732 733 if (priv->obj_flags[o] & CC770_OBJ_FLAG_RTR) 734 cc770_rtr_interrupt(dev, o); 735 else if (priv->obj_flags[o] & CC770_OBJ_FLAG_RX) 736 cc770_rx_interrupt(dev, o); 737 else 738 cc770_tx_interrupt(dev, o); 739 } 740 } 741 742 if (priv->post_irq) 743 priv->post_irq(priv); 744 745 if (n >= CC770_MAX_IRQ) 746 netdev_dbg(dev, "%d messages handled in ISR", n); 747 748 return (n) ? IRQ_HANDLED : IRQ_NONE; 749} 750 751static int cc770_open(struct net_device *dev) 752{ 753 struct cc770_priv *priv = netdev_priv(dev); 754 int err; 755 756 /* set chip into reset mode */ 757 set_reset_mode(dev); 758 759 /* common open */ 760 err = open_candev(dev); 761 if (err) 762 return err; 763 764 err = request_irq(dev->irq, &cc770_interrupt, priv->irq_flags, 765 dev->name, dev); 766 if (err) { 767 close_candev(dev); 768 return -EAGAIN; 769 } 770 771 /* init and start chip */ 772 cc770_start(dev); 773 774 netif_start_queue(dev); 775 776 return 0; 777} 778 779static int cc770_close(struct net_device *dev) 780{ 781 netif_stop_queue(dev); 782 set_reset_mode(dev); 783 784 free_irq(dev->irq, dev); 785 close_candev(dev); 786 787 return 0; 788} 789 790struct net_device *alloc_cc770dev(int sizeof_priv) 791{ 792 struct net_device *dev; 793 struct cc770_priv *priv; 794 795 dev = alloc_candev(sizeof(struct cc770_priv) + sizeof_priv, 796 CC770_ECHO_SKB_MAX); 797 if (!dev) 798 return NULL; 799 800 priv = netdev_priv(dev); 801 802 priv->dev = dev; 803 priv->can.bittiming_const = &cc770_bittiming_const; 804 priv->can.do_set_bittiming = cc770_set_bittiming; 805 priv->can.do_set_mode = cc770_set_mode; 806 priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES; 807 808 memcpy(priv->obj_flags, cc770_obj_flags, sizeof(cc770_obj_flags)); 809 810 if (sizeof_priv) 811 priv->priv = (void *)priv + sizeof(struct cc770_priv); 812 813 return dev; 814} 815EXPORT_SYMBOL_GPL(alloc_cc770dev); 816 817void free_cc770dev(struct net_device *dev) 818{ 819 free_candev(dev); 820} 821EXPORT_SYMBOL_GPL(free_cc770dev); 822 823static const struct net_device_ops cc770_netdev_ops = { 824 .ndo_open = cc770_open, 825 .ndo_stop = cc770_close, 826 .ndo_start_xmit = cc770_start_xmit, 827}; 828 829int register_cc770dev(struct net_device *dev) 830{ 831 struct cc770_priv *priv = netdev_priv(dev); 832 int err; 833 834 err = cc770_probe_chip(dev); 835 if (err) 836 return err; 837 838 dev->netdev_ops = &cc770_netdev_ops; 839 840 dev->flags |= IFF_ECHO; /* we support local echo */ 841 842 /* Should we use additional functions? */ 843 if (!i82527_compat && priv->control_normal_mode & CTRL_EAF) { 844 priv->can.do_get_berr_counter = cc770_get_berr_counter; 845 priv->control_normal_mode = CTRL_IE | CTRL_EAF | CTRL_EIE; 846 netdev_dbg(dev, "i82527 mode with additional functions\n"); 847 } else { 848 priv->control_normal_mode = CTRL_IE | CTRL_EIE; 849 netdev_dbg(dev, "strict i82527 compatibility mode\n"); 850 } 851 852 chipset_init(priv); 853 set_reset_mode(dev); 854 855 return register_candev(dev); 856} 857EXPORT_SYMBOL_GPL(register_cc770dev); 858 859void unregister_cc770dev(struct net_device *dev) 860{ 861 set_reset_mode(dev); 862 unregister_candev(dev); 863} 864EXPORT_SYMBOL_GPL(unregister_cc770dev); 865 866static __init int cc770_init(void) 867{ 868 if (msgobj15_eff) { 869 cc770_obj_flags[CC770_OBJ_RX0] |= CC770_OBJ_FLAG_EFF; 870 cc770_obj_flags[CC770_OBJ_RX1] &= ~CC770_OBJ_FLAG_EFF; 871 } 872 873 pr_info("CAN netdevice driver\n"); 874 875 return 0; 876} 877module_init(cc770_init); 878 879static __exit void cc770_exit(void) 880{ 881 pr_info("driver removed\n"); 882} 883module_exit(cc770_exit); 884