1 // SPDX-License-Identifier: GPL-2.0-only 2 /* CAN bus driver for Microchip 251x/25625 CAN Controller with SPI Interface 3 * 4 * MCP2510 support and bug fixes by Christian Pellegrin 5 * <chripell@evolware.org> 6 * 7 * Copyright 2009 Christian Pellegrin EVOL S.r.l. 8 * 9 * Copyright 2007 Raymarine UK, Ltd. All Rights Reserved. 10 * Written under contract by: 11 * Chris Elston, Katalix Systems, Ltd. 12 * 13 * Based on Microchip MCP251x CAN controller driver written by 14 * David Vrabel, Copyright 2006 Arcom Control Systems Ltd. 15 * 16 * Based on CAN bus driver for the CCAN controller written by 17 * - Sascha Hauer, Marc Kleine-Budde, Pengutronix 18 * - Simon Kallweit, intefo AG 19 * Copyright 2007 20 */ 21 22 #include <linux/bitfield.h> 23 #include <linux/can/core.h> 24 #include <linux/can/dev.h> 25 #include <linux/can/led.h> 26 #include <linux/clk.h> 27 #include <linux/completion.h> 28 #include <linux/delay.h> 29 #include <linux/device.h> 30 #include <linux/freezer.h> 31 #include <linux/gpio.h> 32 #include <linux/gpio/driver.h> 33 #include <linux/interrupt.h> 34 #include <linux/io.h> 35 #include <linux/iopoll.h> 36 #include <linux/kernel.h> 37 #include <linux/module.h> 38 #include <linux/netdevice.h> 39 #include <linux/platform_device.h> 40 #include <linux/property.h> 41 #include <linux/regulator/consumer.h> 42 #include <linux/slab.h> 43 #include <linux/spi/spi.h> 44 #include <linux/uaccess.h> 45 46 /* SPI interface instruction set */ 47 #define INSTRUCTION_WRITE 0x02 48 #define INSTRUCTION_READ 0x03 49 #define INSTRUCTION_BIT_MODIFY 0x05 50 #define INSTRUCTION_LOAD_TXB(n) (0x40 + 2 * (n)) 51 #define INSTRUCTION_READ_RXB(n) (((n) == 0) ? 0x90 : 0x94) 52 #define INSTRUCTION_RESET 0xC0 53 #define RTS_TXB0 0x01 54 #define RTS_TXB1 0x02 55 #define RTS_TXB2 0x04 56 #define INSTRUCTION_RTS(n) (0x80 | ((n) & 0x07)) 57 58 /* MPC251x registers */ 59 #define BFPCTRL 0x0c 60 # define BFPCTRL_B0BFM BIT(0) 61 # define BFPCTRL_B1BFM BIT(1) 62 # define BFPCTRL_BFM(n) (BFPCTRL_B0BFM << (n)) 63 # define BFPCTRL_BFM_MASK GENMASK(1, 0) 64 # define BFPCTRL_B0BFE BIT(2) 65 # define BFPCTRL_B1BFE BIT(3) 66 # define BFPCTRL_BFE(n) (BFPCTRL_B0BFE << (n)) 67 # define BFPCTRL_BFE_MASK GENMASK(3, 2) 68 # define BFPCTRL_B0BFS BIT(4) 69 # define BFPCTRL_B1BFS BIT(5) 70 # define BFPCTRL_BFS(n) (BFPCTRL_B0BFS << (n)) 71 # define BFPCTRL_BFS_MASK GENMASK(5, 4) 72 #define TXRTSCTRL 0x0d 73 # define TXRTSCTRL_B0RTSM BIT(0) 74 # define TXRTSCTRL_B1RTSM BIT(1) 75 # define TXRTSCTRL_B2RTSM BIT(2) 76 # define TXRTSCTRL_RTSM(n) (TXRTSCTRL_B0RTSM << (n)) 77 # define TXRTSCTRL_RTSM_MASK GENMASK(2, 0) 78 # define TXRTSCTRL_B0RTS BIT(3) 79 # define TXRTSCTRL_B1RTS BIT(4) 80 # define TXRTSCTRL_B2RTS BIT(5) 81 # define TXRTSCTRL_RTS(n) (TXRTSCTRL_B0RTS << (n)) 82 # define TXRTSCTRL_RTS_MASK GENMASK(5, 3) 83 #define CANSTAT 0x0e 84 #define CANCTRL 0x0f 85 # define CANCTRL_REQOP_MASK 0xe0 86 # define CANCTRL_REQOP_CONF 0x80 87 # define CANCTRL_REQOP_LISTEN_ONLY 0x60 88 # define CANCTRL_REQOP_LOOPBACK 0x40 89 # define CANCTRL_REQOP_SLEEP 0x20 90 # define CANCTRL_REQOP_NORMAL 0x00 91 # define CANCTRL_OSM 0x08 92 # define CANCTRL_ABAT 0x10 93 #define TEC 0x1c 94 #define REC 0x1d 95 #define CNF1 0x2a 96 # define CNF1_SJW_SHIFT 6 97 #define CNF2 0x29 98 # define CNF2_BTLMODE 0x80 99 # define CNF2_SAM 0x40 100 # define CNF2_PS1_SHIFT 3 101 #define CNF3 0x28 102 # define CNF3_SOF 0x08 103 # define CNF3_WAKFIL 0x04 104 # define CNF3_PHSEG2_MASK 0x07 105 #define CANINTE 0x2b 106 # define CANINTE_MERRE 0x80 107 # define CANINTE_WAKIE 0x40 108 # define CANINTE_ERRIE 0x20 109 # define CANINTE_TX2IE 0x10 110 # define CANINTE_TX1IE 0x08 111 # define CANINTE_TX0IE 0x04 112 # define CANINTE_RX1IE 0x02 113 # define CANINTE_RX0IE 0x01 114 #define CANINTF 0x2c 115 # define CANINTF_MERRF 0x80 116 # define CANINTF_WAKIF 0x40 117 # define CANINTF_ERRIF 0x20 118 # define CANINTF_TX2IF 0x10 119 # define CANINTF_TX1IF 0x08 120 # define CANINTF_TX0IF 0x04 121 # define CANINTF_RX1IF 0x02 122 # define CANINTF_RX0IF 0x01 123 # define CANINTF_RX (CANINTF_RX0IF | CANINTF_RX1IF) 124 # define CANINTF_TX (CANINTF_TX2IF | CANINTF_TX1IF | CANINTF_TX0IF) 125 # define CANINTF_ERR (CANINTF_ERRIF) 126 #define EFLG 0x2d 127 # define EFLG_EWARN 0x01 128 # define EFLG_RXWAR 0x02 129 # define EFLG_TXWAR 0x04 130 # define EFLG_RXEP 0x08 131 # define EFLG_TXEP 0x10 132 # define EFLG_TXBO 0x20 133 # define EFLG_RX0OVR 0x40 134 # define EFLG_RX1OVR 0x80 135 #define TXBCTRL(n) (((n) * 0x10) + 0x30 + TXBCTRL_OFF) 136 # define TXBCTRL_ABTF 0x40 137 # define TXBCTRL_MLOA 0x20 138 # define TXBCTRL_TXERR 0x10 139 # define TXBCTRL_TXREQ 0x08 140 #define TXBSIDH(n) (((n) * 0x10) + 0x30 + TXBSIDH_OFF) 141 # define SIDH_SHIFT 3 142 #define TXBSIDL(n) (((n) * 0x10) + 0x30 + TXBSIDL_OFF) 143 # define SIDL_SID_MASK 7 144 # define SIDL_SID_SHIFT 5 145 # define SIDL_EXIDE_SHIFT 3 146 # define SIDL_EID_SHIFT 16 147 # define SIDL_EID_MASK 3 148 #define TXBEID8(n) (((n) * 0x10) + 0x30 + TXBEID8_OFF) 149 #define TXBEID0(n) (((n) * 0x10) + 0x30 + TXBEID0_OFF) 150 #define TXBDLC(n) (((n) * 0x10) + 0x30 + TXBDLC_OFF) 151 # define DLC_RTR_SHIFT 6 152 #define TXBCTRL_OFF 0 153 #define TXBSIDH_OFF 1 154 #define TXBSIDL_OFF 2 155 #define TXBEID8_OFF 3 156 #define TXBEID0_OFF 4 157 #define TXBDLC_OFF 5 158 #define TXBDAT_OFF 6 159 #define RXBCTRL(n) (((n) * 0x10) + 0x60 + RXBCTRL_OFF) 160 # define RXBCTRL_BUKT 0x04 161 # define RXBCTRL_RXM0 0x20 162 # define RXBCTRL_RXM1 0x40 163 #define RXBSIDH(n) (((n) * 0x10) + 0x60 + RXBSIDH_OFF) 164 # define RXBSIDH_SHIFT 3 165 #define RXBSIDL(n) (((n) * 0x10) + 0x60 + RXBSIDL_OFF) 166 # define RXBSIDL_IDE 0x08 167 # define RXBSIDL_SRR 0x10 168 # define RXBSIDL_EID 3 169 # define RXBSIDL_SHIFT 5 170 #define RXBEID8(n) (((n) * 0x10) + 0x60 + RXBEID8_OFF) 171 #define RXBEID0(n) (((n) * 0x10) + 0x60 + RXBEID0_OFF) 172 #define RXBDLC(n) (((n) * 0x10) + 0x60 + RXBDLC_OFF) 173 # define RXBDLC_LEN_MASK 0x0f 174 # define RXBDLC_RTR 0x40 175 #define RXBCTRL_OFF 0 176 #define RXBSIDH_OFF 1 177 #define RXBSIDL_OFF 2 178 #define RXBEID8_OFF 3 179 #define RXBEID0_OFF 4 180 #define RXBDLC_OFF 5 181 #define RXBDAT_OFF 6 182 #define RXFSID(n) ((n < 3) ? 0 : 4) 183 #define RXFSIDH(n) ((n) * 4 + RXFSID(n)) 184 #define RXFSIDL(n) ((n) * 4 + 1 + RXFSID(n)) 185 #define RXFEID8(n) ((n) * 4 + 2 + RXFSID(n)) 186 #define RXFEID0(n) ((n) * 4 + 3 + RXFSID(n)) 187 #define RXMSIDH(n) ((n) * 4 + 0x20) 188 #define RXMSIDL(n) ((n) * 4 + 0x21) 189 #define RXMEID8(n) ((n) * 4 + 0x22) 190 #define RXMEID0(n) ((n) * 4 + 0x23) 191 192 #define GET_BYTE(val, byte) \ 193 (((val) >> ((byte) * 8)) & 0xff) 194 #define SET_BYTE(val, byte) \ 195 (((val) & 0xff) << ((byte) * 8)) 196 197 /* Buffer size required for the largest SPI transfer (i.e., reading a 198 * frame) 199 */ 200 #define CAN_FRAME_MAX_DATA_LEN 8 201 #define SPI_TRANSFER_BUF_LEN (6 + CAN_FRAME_MAX_DATA_LEN) 202 #define CAN_FRAME_MAX_BITS 128 203 204 #define TX_ECHO_SKB_MAX 1 205 206 #define MCP251X_OST_DELAY_MS (5) 207 208 #define DEVICE_NAME "mcp251x" 209 210 static const struct can_bittiming_const mcp251x_bittiming_const = { 211 .name = DEVICE_NAME, 212 .tseg1_min = 3, 213 .tseg1_max = 16, 214 .tseg2_min = 2, 215 .tseg2_max = 8, 216 .sjw_max = 4, 217 .brp_min = 1, 218 .brp_max = 64, 219 .brp_inc = 1, 220 }; 221 222 enum mcp251x_model { 223 CAN_MCP251X_MCP2510 = 0x2510, 224 CAN_MCP251X_MCP2515 = 0x2515, 225 CAN_MCP251X_MCP25625 = 0x25625, 226 }; 227 228 struct mcp251x_priv { 229 struct can_priv can; 230 struct net_device *net; 231 struct spi_device *spi; 232 enum mcp251x_model model; 233 234 struct mutex mcp_lock; /* SPI device lock */ 235 236 u8 *spi_tx_buf; 237 u8 *spi_rx_buf; 238 239 struct sk_buff *tx_skb; 240 int tx_len; 241 242 struct workqueue_struct *wq; 243 struct work_struct tx_work; 244 struct work_struct restart_work; 245 246 int force_quit; 247 int after_suspend; 248 #define AFTER_SUSPEND_UP 1 249 #define AFTER_SUSPEND_DOWN 2 250 #define AFTER_SUSPEND_POWER 4 251 #define AFTER_SUSPEND_RESTART 8 252 int restart_tx; 253 struct regulator *power; 254 struct regulator *transceiver; 255 struct clk *clk; 256 #ifdef CONFIG_GPIOLIB 257 struct gpio_chip gpio; 258 u8 reg_bfpctrl; 259 #endif 260 }; 261 262 #define MCP251X_IS(_model) \ 263 static inline int mcp251x_is_##_model(struct spi_device *spi) \ 264 { \ 265 struct mcp251x_priv *priv = spi_get_drvdata(spi); \ 266 return priv->model == CAN_MCP251X_MCP##_model; \ 267 } 268 269 MCP251X_IS(2510); 270 271 static void mcp251x_clean(struct net_device *net) 272 { 273 struct mcp251x_priv *priv = netdev_priv(net); 274 275 if (priv->tx_skb || priv->tx_len) 276 net->stats.tx_errors++; 277 dev_kfree_skb(priv->tx_skb); 278 if (priv->tx_len) 279 can_free_echo_skb(priv->net, 0); 280 priv->tx_skb = NULL; 281 priv->tx_len = 0; 282 } 283 284 /* Note about handling of error return of mcp251x_spi_trans: accessing 285 * registers via SPI is not really different conceptually than using 286 * normal I/O assembler instructions, although it's much more 287 * complicated from a practical POV. So it's not advisable to always 288 * check the return value of this function. Imagine that every 289 * read{b,l}, write{b,l} and friends would be bracketed in "if ( < 0) 290 * error();", it would be a great mess (well there are some situation 291 * when exception handling C++ like could be useful after all). So we 292 * just check that transfers are OK at the beginning of our 293 * conversation with the chip and to avoid doing really nasty things 294 * (like injecting bogus packets in the network stack). 295 */ 296 static int mcp251x_spi_trans(struct spi_device *spi, int len) 297 { 298 struct mcp251x_priv *priv = spi_get_drvdata(spi); 299 struct spi_transfer t = { 300 .tx_buf = priv->spi_tx_buf, 301 .rx_buf = priv->spi_rx_buf, 302 .len = len, 303 .cs_change = 0, 304 }; 305 struct spi_message m; 306 int ret; 307 308 spi_message_init(&m); 309 spi_message_add_tail(&t, &m); 310 311 ret = spi_sync(spi, &m); 312 if (ret) 313 dev_err(&spi->dev, "spi transfer failed: ret = %d\n", ret); 314 return ret; 315 } 316 317 static u8 mcp251x_read_reg(struct spi_device *spi, u8 reg) 318 { 319 struct mcp251x_priv *priv = spi_get_drvdata(spi); 320 u8 val = 0; 321 322 priv->spi_tx_buf[0] = INSTRUCTION_READ; 323 priv->spi_tx_buf[1] = reg; 324 325 if (spi->controller->flags & SPI_CONTROLLER_HALF_DUPLEX) { 326 spi_write_then_read(spi, priv->spi_tx_buf, 2, &val, 1); 327 } else { 328 mcp251x_spi_trans(spi, 3); 329 val = priv->spi_rx_buf[2]; 330 } 331 332 return val; 333 } 334 335 static void mcp251x_read_2regs(struct spi_device *spi, u8 reg, u8 *v1, u8 *v2) 336 { 337 struct mcp251x_priv *priv = spi_get_drvdata(spi); 338 339 priv->spi_tx_buf[0] = INSTRUCTION_READ; 340 priv->spi_tx_buf[1] = reg; 341 342 if (spi->controller->flags & SPI_CONTROLLER_HALF_DUPLEX) { 343 u8 val[2] = { 0 }; 344 345 spi_write_then_read(spi, priv->spi_tx_buf, 2, val, 2); 346 *v1 = val[0]; 347 *v2 = val[1]; 348 } else { 349 mcp251x_spi_trans(spi, 4); 350 351 *v1 = priv->spi_rx_buf[2]; 352 *v2 = priv->spi_rx_buf[3]; 353 } 354 } 355 356 static void mcp251x_write_reg(struct spi_device *spi, u8 reg, u8 val) 357 { 358 struct mcp251x_priv *priv = spi_get_drvdata(spi); 359 360 priv->spi_tx_buf[0] = INSTRUCTION_WRITE; 361 priv->spi_tx_buf[1] = reg; 362 priv->spi_tx_buf[2] = val; 363 364 mcp251x_spi_trans(spi, 3); 365 } 366 367 static void mcp251x_write_2regs(struct spi_device *spi, u8 reg, u8 v1, u8 v2) 368 { 369 struct mcp251x_priv *priv = spi_get_drvdata(spi); 370 371 priv->spi_tx_buf[0] = INSTRUCTION_WRITE; 372 priv->spi_tx_buf[1] = reg; 373 priv->spi_tx_buf[2] = v1; 374 priv->spi_tx_buf[3] = v2; 375 376 mcp251x_spi_trans(spi, 4); 377 } 378 379 static void mcp251x_write_bits(struct spi_device *spi, u8 reg, 380 u8 mask, u8 val) 381 { 382 struct mcp251x_priv *priv = spi_get_drvdata(spi); 383 384 priv->spi_tx_buf[0] = INSTRUCTION_BIT_MODIFY; 385 priv->spi_tx_buf[1] = reg; 386 priv->spi_tx_buf[2] = mask; 387 priv->spi_tx_buf[3] = val; 388 389 mcp251x_spi_trans(spi, 4); 390 } 391 392 static u8 mcp251x_read_stat(struct spi_device *spi) 393 { 394 return mcp251x_read_reg(spi, CANSTAT) & CANCTRL_REQOP_MASK; 395 } 396 397 #define mcp251x_read_stat_poll_timeout(addr, val, cond, delay_us, timeout_us) \ 398 readx_poll_timeout(mcp251x_read_stat, addr, val, cond, \ 399 delay_us, timeout_us) 400 401 #ifdef CONFIG_GPIOLIB 402 enum { 403 MCP251X_GPIO_TX0RTS = 0, /* inputs */ 404 MCP251X_GPIO_TX1RTS, 405 MCP251X_GPIO_TX2RTS, 406 MCP251X_GPIO_RX0BF, /* outputs */ 407 MCP251X_GPIO_RX1BF, 408 }; 409 410 #define MCP251X_GPIO_INPUT_MASK \ 411 GENMASK(MCP251X_GPIO_TX2RTS, MCP251X_GPIO_TX0RTS) 412 #define MCP251X_GPIO_OUTPUT_MASK \ 413 GENMASK(MCP251X_GPIO_RX1BF, MCP251X_GPIO_RX0BF) 414 415 static const char * const mcp251x_gpio_names[] = { 416 [MCP251X_GPIO_TX0RTS] = "TX0RTS", /* inputs */ 417 [MCP251X_GPIO_TX1RTS] = "TX1RTS", 418 [MCP251X_GPIO_TX2RTS] = "TX2RTS", 419 [MCP251X_GPIO_RX0BF] = "RX0BF", /* outputs */ 420 [MCP251X_GPIO_RX1BF] = "RX1BF", 421 }; 422 423 static inline bool mcp251x_gpio_is_input(unsigned int offset) 424 { 425 return offset <= MCP251X_GPIO_TX2RTS; 426 } 427 428 static int mcp251x_gpio_request(struct gpio_chip *chip, 429 unsigned int offset) 430 { 431 struct mcp251x_priv *priv = gpiochip_get_data(chip); 432 u8 val; 433 434 /* nothing to be done for inputs */ 435 if (mcp251x_gpio_is_input(offset)) 436 return 0; 437 438 val = BFPCTRL_BFE(offset - MCP251X_GPIO_RX0BF); 439 440 mutex_lock(&priv->mcp_lock); 441 mcp251x_write_bits(priv->spi, BFPCTRL, val, val); 442 mutex_unlock(&priv->mcp_lock); 443 444 priv->reg_bfpctrl |= val; 445 446 return 0; 447 } 448 449 static void mcp251x_gpio_free(struct gpio_chip *chip, 450 unsigned int offset) 451 { 452 struct mcp251x_priv *priv = gpiochip_get_data(chip); 453 u8 val; 454 455 /* nothing to be done for inputs */ 456 if (mcp251x_gpio_is_input(offset)) 457 return; 458 459 val = BFPCTRL_BFE(offset - MCP251X_GPIO_RX0BF); 460 461 mutex_lock(&priv->mcp_lock); 462 mcp251x_write_bits(priv->spi, BFPCTRL, val, 0); 463 mutex_unlock(&priv->mcp_lock); 464 465 priv->reg_bfpctrl &= ~val; 466 } 467 468 static int mcp251x_gpio_get_direction(struct gpio_chip *chip, 469 unsigned int offset) 470 { 471 if (mcp251x_gpio_is_input(offset)) 472 return GPIOF_DIR_IN; 473 474 return GPIOF_DIR_OUT; 475 } 476 477 static int mcp251x_gpio_get(struct gpio_chip *chip, unsigned int offset) 478 { 479 struct mcp251x_priv *priv = gpiochip_get_data(chip); 480 u8 reg, mask, val; 481 482 if (mcp251x_gpio_is_input(offset)) { 483 reg = TXRTSCTRL; 484 mask = TXRTSCTRL_RTS(offset); 485 } else { 486 reg = BFPCTRL; 487 mask = BFPCTRL_BFS(offset - MCP251X_GPIO_RX0BF); 488 } 489 490 mutex_lock(&priv->mcp_lock); 491 val = mcp251x_read_reg(priv->spi, reg); 492 mutex_unlock(&priv->mcp_lock); 493 494 return !!(val & mask); 495 } 496 497 static int mcp251x_gpio_get_multiple(struct gpio_chip *chip, 498 unsigned long *maskp, unsigned long *bitsp) 499 { 500 struct mcp251x_priv *priv = gpiochip_get_data(chip); 501 unsigned long bits = 0; 502 u8 val; 503 504 mutex_lock(&priv->mcp_lock); 505 if (maskp[0] & MCP251X_GPIO_INPUT_MASK) { 506 val = mcp251x_read_reg(priv->spi, TXRTSCTRL); 507 val = FIELD_GET(TXRTSCTRL_RTS_MASK, val); 508 bits |= FIELD_PREP(MCP251X_GPIO_INPUT_MASK, val); 509 } 510 if (maskp[0] & MCP251X_GPIO_OUTPUT_MASK) { 511 val = mcp251x_read_reg(priv->spi, BFPCTRL); 512 val = FIELD_GET(BFPCTRL_BFS_MASK, val); 513 bits |= FIELD_PREP(MCP251X_GPIO_OUTPUT_MASK, val); 514 } 515 mutex_unlock(&priv->mcp_lock); 516 517 bitsp[0] = bits; 518 return 0; 519 } 520 521 static void mcp251x_gpio_set(struct gpio_chip *chip, unsigned int offset, 522 int value) 523 { 524 struct mcp251x_priv *priv = gpiochip_get_data(chip); 525 u8 mask, val; 526 527 mask = BFPCTRL_BFS(offset - MCP251X_GPIO_RX0BF); 528 val = value ? mask : 0; 529 530 mutex_lock(&priv->mcp_lock); 531 mcp251x_write_bits(priv->spi, BFPCTRL, mask, val); 532 mutex_unlock(&priv->mcp_lock); 533 534 priv->reg_bfpctrl &= ~mask; 535 priv->reg_bfpctrl |= val; 536 } 537 538 static void 539 mcp251x_gpio_set_multiple(struct gpio_chip *chip, 540 unsigned long *maskp, unsigned long *bitsp) 541 { 542 struct mcp251x_priv *priv = gpiochip_get_data(chip); 543 u8 mask, val; 544 545 mask = FIELD_GET(MCP251X_GPIO_OUTPUT_MASK, maskp[0]); 546 mask = FIELD_PREP(BFPCTRL_BFS_MASK, mask); 547 548 val = FIELD_GET(MCP251X_GPIO_OUTPUT_MASK, bitsp[0]); 549 val = FIELD_PREP(BFPCTRL_BFS_MASK, val); 550 551 if (!mask) 552 return; 553 554 mutex_lock(&priv->mcp_lock); 555 mcp251x_write_bits(priv->spi, BFPCTRL, mask, val); 556 mutex_unlock(&priv->mcp_lock); 557 558 priv->reg_bfpctrl &= ~mask; 559 priv->reg_bfpctrl |= val; 560 } 561 562 static void mcp251x_gpio_restore(struct spi_device *spi) 563 { 564 struct mcp251x_priv *priv = spi_get_drvdata(spi); 565 566 mcp251x_write_reg(spi, BFPCTRL, priv->reg_bfpctrl); 567 } 568 569 static int mcp251x_gpio_setup(struct mcp251x_priv *priv) 570 { 571 struct gpio_chip *gpio = &priv->gpio; 572 573 if (!device_property_present(&priv->spi->dev, "gpio-controller")) 574 return 0; 575 576 /* gpiochip handles TX[0..2]RTS and RX[0..1]BF */ 577 gpio->label = priv->spi->modalias; 578 gpio->parent = &priv->spi->dev; 579 gpio->owner = THIS_MODULE; 580 gpio->request = mcp251x_gpio_request; 581 gpio->free = mcp251x_gpio_free; 582 gpio->get_direction = mcp251x_gpio_get_direction; 583 gpio->get = mcp251x_gpio_get; 584 gpio->get_multiple = mcp251x_gpio_get_multiple; 585 gpio->set = mcp251x_gpio_set; 586 gpio->set_multiple = mcp251x_gpio_set_multiple; 587 gpio->base = -1; 588 gpio->ngpio = ARRAY_SIZE(mcp251x_gpio_names); 589 gpio->names = mcp251x_gpio_names; 590 gpio->can_sleep = true; 591 #ifdef CONFIG_OF_GPIO 592 gpio->of_node = priv->spi->dev.of_node; 593 #endif 594 595 return devm_gpiochip_add_data(&priv->spi->dev, gpio, priv); 596 } 597 #else 598 static inline void mcp251x_gpio_restore(struct spi_device *spi) 599 { 600 } 601 602 static inline int mcp251x_gpio_setup(struct mcp251x_priv *priv) 603 { 604 return 0; 605 } 606 #endif 607 608 static void mcp251x_hw_tx_frame(struct spi_device *spi, u8 *buf, 609 int len, int tx_buf_idx) 610 { 611 struct mcp251x_priv *priv = spi_get_drvdata(spi); 612 613 if (mcp251x_is_2510(spi)) { 614 int i; 615 616 for (i = 1; i < TXBDAT_OFF + len; i++) 617 mcp251x_write_reg(spi, TXBCTRL(tx_buf_idx) + i, 618 buf[i]); 619 } else { 620 memcpy(priv->spi_tx_buf, buf, TXBDAT_OFF + len); 621 mcp251x_spi_trans(spi, TXBDAT_OFF + len); 622 } 623 } 624 625 static void mcp251x_hw_tx(struct spi_device *spi, struct can_frame *frame, 626 int tx_buf_idx) 627 { 628 struct mcp251x_priv *priv = spi_get_drvdata(spi); 629 u32 sid, eid, exide, rtr; 630 u8 buf[SPI_TRANSFER_BUF_LEN]; 631 632 exide = (frame->can_id & CAN_EFF_FLAG) ? 1 : 0; /* Extended ID Enable */ 633 if (exide) 634 sid = (frame->can_id & CAN_EFF_MASK) >> 18; 635 else 636 sid = frame->can_id & CAN_SFF_MASK; /* Standard ID */ 637 eid = frame->can_id & CAN_EFF_MASK; /* Extended ID */ 638 rtr = (frame->can_id & CAN_RTR_FLAG) ? 1 : 0; /* Remote transmission */ 639 640 buf[TXBCTRL_OFF] = INSTRUCTION_LOAD_TXB(tx_buf_idx); 641 buf[TXBSIDH_OFF] = sid >> SIDH_SHIFT; 642 buf[TXBSIDL_OFF] = ((sid & SIDL_SID_MASK) << SIDL_SID_SHIFT) | 643 (exide << SIDL_EXIDE_SHIFT) | 644 ((eid >> SIDL_EID_SHIFT) & SIDL_EID_MASK); 645 buf[TXBEID8_OFF] = GET_BYTE(eid, 1); 646 buf[TXBEID0_OFF] = GET_BYTE(eid, 0); 647 buf[TXBDLC_OFF] = (rtr << DLC_RTR_SHIFT) | frame->len; 648 memcpy(buf + TXBDAT_OFF, frame->data, frame->len); 649 mcp251x_hw_tx_frame(spi, buf, frame->len, tx_buf_idx); 650 651 /* use INSTRUCTION_RTS, to avoid "repeated frame problem" */ 652 priv->spi_tx_buf[0] = INSTRUCTION_RTS(1 << tx_buf_idx); 653 mcp251x_spi_trans(priv->spi, 1); 654 } 655 656 static void mcp251x_hw_rx_frame(struct spi_device *spi, u8 *buf, 657 int buf_idx) 658 { 659 struct mcp251x_priv *priv = spi_get_drvdata(spi); 660 661 if (mcp251x_is_2510(spi)) { 662 int i, len; 663 664 for (i = 1; i < RXBDAT_OFF; i++) 665 buf[i] = mcp251x_read_reg(spi, RXBCTRL(buf_idx) + i); 666 667 len = can_cc_dlc2len(buf[RXBDLC_OFF] & RXBDLC_LEN_MASK); 668 for (; i < (RXBDAT_OFF + len); i++) 669 buf[i] = mcp251x_read_reg(spi, RXBCTRL(buf_idx) + i); 670 } else { 671 priv->spi_tx_buf[RXBCTRL_OFF] = INSTRUCTION_READ_RXB(buf_idx); 672 if (spi->controller->flags & SPI_CONTROLLER_HALF_DUPLEX) { 673 spi_write_then_read(spi, priv->spi_tx_buf, 1, 674 priv->spi_rx_buf, 675 SPI_TRANSFER_BUF_LEN); 676 memcpy(buf + 1, priv->spi_rx_buf, 677 SPI_TRANSFER_BUF_LEN - 1); 678 } else { 679 mcp251x_spi_trans(spi, SPI_TRANSFER_BUF_LEN); 680 memcpy(buf, priv->spi_rx_buf, SPI_TRANSFER_BUF_LEN); 681 } 682 } 683 } 684 685 static void mcp251x_hw_rx(struct spi_device *spi, int buf_idx) 686 { 687 struct mcp251x_priv *priv = spi_get_drvdata(spi); 688 struct sk_buff *skb; 689 struct can_frame *frame; 690 u8 buf[SPI_TRANSFER_BUF_LEN]; 691 692 skb = alloc_can_skb(priv->net, &frame); 693 if (!skb) { 694 dev_err(&spi->dev, "cannot allocate RX skb\n"); 695 priv->net->stats.rx_dropped++; 696 return; 697 } 698 699 mcp251x_hw_rx_frame(spi, buf, buf_idx); 700 if (buf[RXBSIDL_OFF] & RXBSIDL_IDE) { 701 /* Extended ID format */ 702 frame->can_id = CAN_EFF_FLAG; 703 frame->can_id |= 704 /* Extended ID part */ 705 SET_BYTE(buf[RXBSIDL_OFF] & RXBSIDL_EID, 2) | 706 SET_BYTE(buf[RXBEID8_OFF], 1) | 707 SET_BYTE(buf[RXBEID0_OFF], 0) | 708 /* Standard ID part */ 709 (((buf[RXBSIDH_OFF] << RXBSIDH_SHIFT) | 710 (buf[RXBSIDL_OFF] >> RXBSIDL_SHIFT)) << 18); 711 /* Remote transmission request */ 712 if (buf[RXBDLC_OFF] & RXBDLC_RTR) 713 frame->can_id |= CAN_RTR_FLAG; 714 } else { 715 /* Standard ID format */ 716 frame->can_id = 717 (buf[RXBSIDH_OFF] << RXBSIDH_SHIFT) | 718 (buf[RXBSIDL_OFF] >> RXBSIDL_SHIFT); 719 if (buf[RXBSIDL_OFF] & RXBSIDL_SRR) 720 frame->can_id |= CAN_RTR_FLAG; 721 } 722 /* Data length */ 723 frame->len = can_cc_dlc2len(buf[RXBDLC_OFF] & RXBDLC_LEN_MASK); 724 memcpy(frame->data, buf + RXBDAT_OFF, frame->len); 725 726 priv->net->stats.rx_packets++; 727 priv->net->stats.rx_bytes += frame->len; 728 729 can_led_event(priv->net, CAN_LED_EVENT_RX); 730 731 netif_rx_ni(skb); 732 } 733 734 static void mcp251x_hw_sleep(struct spi_device *spi) 735 { 736 mcp251x_write_reg(spi, CANCTRL, CANCTRL_REQOP_SLEEP); 737 } 738 739 /* May only be called when device is sleeping! */ 740 static int mcp251x_hw_wake(struct spi_device *spi) 741 { 742 u8 value; 743 int ret; 744 745 /* Force wakeup interrupt to wake device, but don't execute IST */ 746 disable_irq(spi->irq); 747 mcp251x_write_2regs(spi, CANINTE, CANINTE_WAKIE, CANINTF_WAKIF); 748 749 /* Wait for oscillator startup timer after wake up */ 750 mdelay(MCP251X_OST_DELAY_MS); 751 752 /* Put device into config mode */ 753 mcp251x_write_reg(spi, CANCTRL, CANCTRL_REQOP_CONF); 754 755 /* Wait for the device to enter config mode */ 756 ret = mcp251x_read_stat_poll_timeout(spi, value, value == CANCTRL_REQOP_CONF, 757 MCP251X_OST_DELAY_MS * 1000, 758 USEC_PER_SEC); 759 if (ret) { 760 dev_err(&spi->dev, "MCP251x didn't enter in config mode\n"); 761 return ret; 762 } 763 764 /* Disable and clear pending interrupts */ 765 mcp251x_write_2regs(spi, CANINTE, 0x00, 0x00); 766 enable_irq(spi->irq); 767 768 return 0; 769 } 770 771 static netdev_tx_t mcp251x_hard_start_xmit(struct sk_buff *skb, 772 struct net_device *net) 773 { 774 struct mcp251x_priv *priv = netdev_priv(net); 775 struct spi_device *spi = priv->spi; 776 777 if (priv->tx_skb || priv->tx_len) { 778 dev_warn(&spi->dev, "hard_xmit called while tx busy\n"); 779 return NETDEV_TX_BUSY; 780 } 781 782 if (can_dropped_invalid_skb(net, skb)) 783 return NETDEV_TX_OK; 784 785 netif_stop_queue(net); 786 priv->tx_skb = skb; 787 queue_work(priv->wq, &priv->tx_work); 788 789 return NETDEV_TX_OK; 790 } 791 792 static int mcp251x_do_set_mode(struct net_device *net, enum can_mode mode) 793 { 794 struct mcp251x_priv *priv = netdev_priv(net); 795 796 switch (mode) { 797 case CAN_MODE_START: 798 mcp251x_clean(net); 799 /* We have to delay work since SPI I/O may sleep */ 800 priv->can.state = CAN_STATE_ERROR_ACTIVE; 801 priv->restart_tx = 1; 802 if (priv->can.restart_ms == 0) 803 priv->after_suspend = AFTER_SUSPEND_RESTART; 804 queue_work(priv->wq, &priv->restart_work); 805 break; 806 default: 807 return -EOPNOTSUPP; 808 } 809 810 return 0; 811 } 812 813 static int mcp251x_set_normal_mode(struct spi_device *spi) 814 { 815 struct mcp251x_priv *priv = spi_get_drvdata(spi); 816 u8 value; 817 int ret; 818 819 /* Enable interrupts */ 820 mcp251x_write_reg(spi, CANINTE, 821 CANINTE_ERRIE | CANINTE_TX2IE | CANINTE_TX1IE | 822 CANINTE_TX0IE | CANINTE_RX1IE | CANINTE_RX0IE); 823 824 if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK) { 825 /* Put device into loopback mode */ 826 mcp251x_write_reg(spi, CANCTRL, CANCTRL_REQOP_LOOPBACK); 827 } else if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY) { 828 /* Put device into listen-only mode */ 829 mcp251x_write_reg(spi, CANCTRL, CANCTRL_REQOP_LISTEN_ONLY); 830 } else { 831 /* Put device into normal mode */ 832 mcp251x_write_reg(spi, CANCTRL, CANCTRL_REQOP_NORMAL); 833 834 /* Wait for the device to enter normal mode */ 835 ret = mcp251x_read_stat_poll_timeout(spi, value, value == 0, 836 MCP251X_OST_DELAY_MS * 1000, 837 USEC_PER_SEC); 838 if (ret) { 839 dev_err(&spi->dev, "MCP251x didn't enter in normal mode\n"); 840 return ret; 841 } 842 } 843 priv->can.state = CAN_STATE_ERROR_ACTIVE; 844 return 0; 845 } 846 847 static int mcp251x_do_set_bittiming(struct net_device *net) 848 { 849 struct mcp251x_priv *priv = netdev_priv(net); 850 struct can_bittiming *bt = &priv->can.bittiming; 851 struct spi_device *spi = priv->spi; 852 853 mcp251x_write_reg(spi, CNF1, ((bt->sjw - 1) << CNF1_SJW_SHIFT) | 854 (bt->brp - 1)); 855 mcp251x_write_reg(spi, CNF2, CNF2_BTLMODE | 856 (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES ? 857 CNF2_SAM : 0) | 858 ((bt->phase_seg1 - 1) << CNF2_PS1_SHIFT) | 859 (bt->prop_seg - 1)); 860 mcp251x_write_bits(spi, CNF3, CNF3_PHSEG2_MASK, 861 (bt->phase_seg2 - 1)); 862 dev_dbg(&spi->dev, "CNF: 0x%02x 0x%02x 0x%02x\n", 863 mcp251x_read_reg(spi, CNF1), 864 mcp251x_read_reg(spi, CNF2), 865 mcp251x_read_reg(spi, CNF3)); 866 867 return 0; 868 } 869 870 static int mcp251x_setup(struct net_device *net, struct spi_device *spi) 871 { 872 mcp251x_do_set_bittiming(net); 873 874 mcp251x_write_reg(spi, RXBCTRL(0), 875 RXBCTRL_BUKT | RXBCTRL_RXM0 | RXBCTRL_RXM1); 876 mcp251x_write_reg(spi, RXBCTRL(1), 877 RXBCTRL_RXM0 | RXBCTRL_RXM1); 878 return 0; 879 } 880 881 static int mcp251x_hw_reset(struct spi_device *spi) 882 { 883 struct mcp251x_priv *priv = spi_get_drvdata(spi); 884 u8 value; 885 int ret; 886 887 /* Wait for oscillator startup timer after power up */ 888 mdelay(MCP251X_OST_DELAY_MS); 889 890 priv->spi_tx_buf[0] = INSTRUCTION_RESET; 891 ret = mcp251x_spi_trans(spi, 1); 892 if (ret) 893 return ret; 894 895 /* Wait for oscillator startup timer after reset */ 896 mdelay(MCP251X_OST_DELAY_MS); 897 898 /* Wait for reset to finish */ 899 ret = mcp251x_read_stat_poll_timeout(spi, value, value == CANCTRL_REQOP_CONF, 900 MCP251X_OST_DELAY_MS * 1000, 901 USEC_PER_SEC); 902 if (ret) 903 dev_err(&spi->dev, "MCP251x didn't enter in conf mode after reset\n"); 904 return ret; 905 } 906 907 static int mcp251x_hw_probe(struct spi_device *spi) 908 { 909 u8 ctrl; 910 int ret; 911 912 ret = mcp251x_hw_reset(spi); 913 if (ret) 914 return ret; 915 916 ctrl = mcp251x_read_reg(spi, CANCTRL); 917 918 dev_dbg(&spi->dev, "CANCTRL 0x%02x\n", ctrl); 919 920 /* Check for power up default value */ 921 if ((ctrl & 0x17) != 0x07) 922 return -ENODEV; 923 924 return 0; 925 } 926 927 static int mcp251x_power_enable(struct regulator *reg, int enable) 928 { 929 if (IS_ERR_OR_NULL(reg)) 930 return 0; 931 932 if (enable) 933 return regulator_enable(reg); 934 else 935 return regulator_disable(reg); 936 } 937 938 static int mcp251x_stop(struct net_device *net) 939 { 940 struct mcp251x_priv *priv = netdev_priv(net); 941 struct spi_device *spi = priv->spi; 942 943 close_candev(net); 944 945 priv->force_quit = 1; 946 free_irq(spi->irq, priv); 947 destroy_workqueue(priv->wq); 948 priv->wq = NULL; 949 950 mutex_lock(&priv->mcp_lock); 951 952 /* Disable and clear pending interrupts */ 953 mcp251x_write_2regs(spi, CANINTE, 0x00, 0x00); 954 955 mcp251x_write_reg(spi, TXBCTRL(0), 0); 956 mcp251x_clean(net); 957 958 mcp251x_hw_sleep(spi); 959 960 mcp251x_power_enable(priv->transceiver, 0); 961 962 priv->can.state = CAN_STATE_STOPPED; 963 964 mutex_unlock(&priv->mcp_lock); 965 966 can_led_event(net, CAN_LED_EVENT_STOP); 967 968 return 0; 969 } 970 971 static void mcp251x_error_skb(struct net_device *net, int can_id, int data1) 972 { 973 struct sk_buff *skb; 974 struct can_frame *frame; 975 976 skb = alloc_can_err_skb(net, &frame); 977 if (skb) { 978 frame->can_id |= can_id; 979 frame->data[1] = data1; 980 netif_rx_ni(skb); 981 } else { 982 netdev_err(net, "cannot allocate error skb\n"); 983 } 984 } 985 986 static void mcp251x_tx_work_handler(struct work_struct *ws) 987 { 988 struct mcp251x_priv *priv = container_of(ws, struct mcp251x_priv, 989 tx_work); 990 struct spi_device *spi = priv->spi; 991 struct net_device *net = priv->net; 992 struct can_frame *frame; 993 994 mutex_lock(&priv->mcp_lock); 995 if (priv->tx_skb) { 996 if (priv->can.state == CAN_STATE_BUS_OFF) { 997 mcp251x_clean(net); 998 } else { 999 frame = (struct can_frame *)priv->tx_skb->data; 1000 1001 if (frame->len > CAN_FRAME_MAX_DATA_LEN) 1002 frame->len = CAN_FRAME_MAX_DATA_LEN; 1003 mcp251x_hw_tx(spi, frame, 0); 1004 priv->tx_len = 1 + frame->len; 1005 can_put_echo_skb(priv->tx_skb, net, 0, 0); 1006 priv->tx_skb = NULL; 1007 } 1008 } 1009 mutex_unlock(&priv->mcp_lock); 1010 } 1011 1012 static void mcp251x_restart_work_handler(struct work_struct *ws) 1013 { 1014 struct mcp251x_priv *priv = container_of(ws, struct mcp251x_priv, 1015 restart_work); 1016 struct spi_device *spi = priv->spi; 1017 struct net_device *net = priv->net; 1018 1019 mutex_lock(&priv->mcp_lock); 1020 if (priv->after_suspend) { 1021 if (priv->after_suspend & AFTER_SUSPEND_POWER) { 1022 mcp251x_hw_reset(spi); 1023 mcp251x_setup(net, spi); 1024 mcp251x_gpio_restore(spi); 1025 } else { 1026 mcp251x_hw_wake(spi); 1027 } 1028 priv->force_quit = 0; 1029 if (priv->after_suspend & AFTER_SUSPEND_RESTART) { 1030 mcp251x_set_normal_mode(spi); 1031 } else if (priv->after_suspend & AFTER_SUSPEND_UP) { 1032 netif_device_attach(net); 1033 mcp251x_clean(net); 1034 mcp251x_set_normal_mode(spi); 1035 netif_wake_queue(net); 1036 } else { 1037 mcp251x_hw_sleep(spi); 1038 } 1039 priv->after_suspend = 0; 1040 } 1041 1042 if (priv->restart_tx) { 1043 priv->restart_tx = 0; 1044 mcp251x_write_reg(spi, TXBCTRL(0), 0); 1045 mcp251x_clean(net); 1046 netif_wake_queue(net); 1047 mcp251x_error_skb(net, CAN_ERR_RESTARTED, 0); 1048 } 1049 mutex_unlock(&priv->mcp_lock); 1050 } 1051 1052 static irqreturn_t mcp251x_can_ist(int irq, void *dev_id) 1053 { 1054 struct mcp251x_priv *priv = dev_id; 1055 struct spi_device *spi = priv->spi; 1056 struct net_device *net = priv->net; 1057 1058 mutex_lock(&priv->mcp_lock); 1059 while (!priv->force_quit) { 1060 enum can_state new_state; 1061 u8 intf, eflag; 1062 u8 clear_intf = 0; 1063 int can_id = 0, data1 = 0; 1064 1065 mcp251x_read_2regs(spi, CANINTF, &intf, &eflag); 1066 1067 /* mask out flags we don't care about */ 1068 intf &= CANINTF_RX | CANINTF_TX | CANINTF_ERR; 1069 1070 /* receive buffer 0 */ 1071 if (intf & CANINTF_RX0IF) { 1072 mcp251x_hw_rx(spi, 0); 1073 /* Free one buffer ASAP 1074 * (The MCP2515/25625 does this automatically.) 1075 */ 1076 if (mcp251x_is_2510(spi)) 1077 mcp251x_write_bits(spi, CANINTF, 1078 CANINTF_RX0IF, 0x00); 1079 } 1080 1081 /* receive buffer 1 */ 1082 if (intf & CANINTF_RX1IF) { 1083 mcp251x_hw_rx(spi, 1); 1084 /* The MCP2515/25625 does this automatically. */ 1085 if (mcp251x_is_2510(spi)) 1086 clear_intf |= CANINTF_RX1IF; 1087 } 1088 1089 /* any error or tx interrupt we need to clear? */ 1090 if (intf & (CANINTF_ERR | CANINTF_TX)) 1091 clear_intf |= intf & (CANINTF_ERR | CANINTF_TX); 1092 if (clear_intf) 1093 mcp251x_write_bits(spi, CANINTF, clear_intf, 0x00); 1094 1095 if (eflag & (EFLG_RX0OVR | EFLG_RX1OVR)) 1096 mcp251x_write_bits(spi, EFLG, eflag, 0x00); 1097 1098 /* Update can state */ 1099 if (eflag & EFLG_TXBO) { 1100 new_state = CAN_STATE_BUS_OFF; 1101 can_id |= CAN_ERR_BUSOFF; 1102 } else if (eflag & EFLG_TXEP) { 1103 new_state = CAN_STATE_ERROR_PASSIVE; 1104 can_id |= CAN_ERR_CRTL; 1105 data1 |= CAN_ERR_CRTL_TX_PASSIVE; 1106 } else if (eflag & EFLG_RXEP) { 1107 new_state = CAN_STATE_ERROR_PASSIVE; 1108 can_id |= CAN_ERR_CRTL; 1109 data1 |= CAN_ERR_CRTL_RX_PASSIVE; 1110 } else if (eflag & EFLG_TXWAR) { 1111 new_state = CAN_STATE_ERROR_WARNING; 1112 can_id |= CAN_ERR_CRTL; 1113 data1 |= CAN_ERR_CRTL_TX_WARNING; 1114 } else if (eflag & EFLG_RXWAR) { 1115 new_state = CAN_STATE_ERROR_WARNING; 1116 can_id |= CAN_ERR_CRTL; 1117 data1 |= CAN_ERR_CRTL_RX_WARNING; 1118 } else { 1119 new_state = CAN_STATE_ERROR_ACTIVE; 1120 } 1121 1122 /* Update can state statistics */ 1123 switch (priv->can.state) { 1124 case CAN_STATE_ERROR_ACTIVE: 1125 if (new_state >= CAN_STATE_ERROR_WARNING && 1126 new_state <= CAN_STATE_BUS_OFF) 1127 priv->can.can_stats.error_warning++; 1128 fallthrough; 1129 case CAN_STATE_ERROR_WARNING: 1130 if (new_state >= CAN_STATE_ERROR_PASSIVE && 1131 new_state <= CAN_STATE_BUS_OFF) 1132 priv->can.can_stats.error_passive++; 1133 break; 1134 default: 1135 break; 1136 } 1137 priv->can.state = new_state; 1138 1139 if (intf & CANINTF_ERRIF) { 1140 /* Handle overflow counters */ 1141 if (eflag & (EFLG_RX0OVR | EFLG_RX1OVR)) { 1142 if (eflag & EFLG_RX0OVR) { 1143 net->stats.rx_over_errors++; 1144 net->stats.rx_errors++; 1145 } 1146 if (eflag & EFLG_RX1OVR) { 1147 net->stats.rx_over_errors++; 1148 net->stats.rx_errors++; 1149 } 1150 can_id |= CAN_ERR_CRTL; 1151 data1 |= CAN_ERR_CRTL_RX_OVERFLOW; 1152 } 1153 mcp251x_error_skb(net, can_id, data1); 1154 } 1155 1156 if (priv->can.state == CAN_STATE_BUS_OFF) { 1157 if (priv->can.restart_ms == 0) { 1158 priv->force_quit = 1; 1159 priv->can.can_stats.bus_off++; 1160 can_bus_off(net); 1161 mcp251x_hw_sleep(spi); 1162 break; 1163 } 1164 } 1165 1166 if (intf == 0) 1167 break; 1168 1169 if (intf & CANINTF_TX) { 1170 net->stats.tx_packets++; 1171 net->stats.tx_bytes += priv->tx_len - 1; 1172 can_led_event(net, CAN_LED_EVENT_TX); 1173 if (priv->tx_len) { 1174 can_get_echo_skb(net, 0, NULL); 1175 priv->tx_len = 0; 1176 } 1177 netif_wake_queue(net); 1178 } 1179 } 1180 mutex_unlock(&priv->mcp_lock); 1181 return IRQ_HANDLED; 1182 } 1183 1184 static int mcp251x_open(struct net_device *net) 1185 { 1186 struct mcp251x_priv *priv = netdev_priv(net); 1187 struct spi_device *spi = priv->spi; 1188 unsigned long flags = 0; 1189 int ret; 1190 1191 ret = open_candev(net); 1192 if (ret) { 1193 dev_err(&spi->dev, "unable to set initial baudrate!\n"); 1194 return ret; 1195 } 1196 1197 mutex_lock(&priv->mcp_lock); 1198 mcp251x_power_enable(priv->transceiver, 1); 1199 1200 priv->force_quit = 0; 1201 priv->tx_skb = NULL; 1202 priv->tx_len = 0; 1203 1204 if (!dev_fwnode(&spi->dev)) 1205 flags = IRQF_TRIGGER_FALLING; 1206 1207 ret = request_threaded_irq(spi->irq, NULL, mcp251x_can_ist, 1208 flags | IRQF_ONESHOT, dev_name(&spi->dev), 1209 priv); 1210 if (ret) { 1211 dev_err(&spi->dev, "failed to acquire irq %d\n", spi->irq); 1212 goto out_close; 1213 } 1214 1215 priv->wq = alloc_workqueue("mcp251x_wq", WQ_FREEZABLE | WQ_MEM_RECLAIM, 1216 0); 1217 if (!priv->wq) { 1218 ret = -ENOMEM; 1219 goto out_clean; 1220 } 1221 INIT_WORK(&priv->tx_work, mcp251x_tx_work_handler); 1222 INIT_WORK(&priv->restart_work, mcp251x_restart_work_handler); 1223 1224 ret = mcp251x_hw_wake(spi); 1225 if (ret) 1226 goto out_free_wq; 1227 ret = mcp251x_setup(net, spi); 1228 if (ret) 1229 goto out_free_wq; 1230 ret = mcp251x_set_normal_mode(spi); 1231 if (ret) 1232 goto out_free_wq; 1233 1234 can_led_event(net, CAN_LED_EVENT_OPEN); 1235 1236 netif_wake_queue(net); 1237 mutex_unlock(&priv->mcp_lock); 1238 1239 return 0; 1240 1241 out_free_wq: 1242 destroy_workqueue(priv->wq); 1243 out_clean: 1244 free_irq(spi->irq, priv); 1245 mcp251x_hw_sleep(spi); 1246 out_close: 1247 mcp251x_power_enable(priv->transceiver, 0); 1248 close_candev(net); 1249 mutex_unlock(&priv->mcp_lock); 1250 return ret; 1251 } 1252 1253 static const struct net_device_ops mcp251x_netdev_ops = { 1254 .ndo_open = mcp251x_open, 1255 .ndo_stop = mcp251x_stop, 1256 .ndo_start_xmit = mcp251x_hard_start_xmit, 1257 .ndo_change_mtu = can_change_mtu, 1258 }; 1259 1260 static const struct of_device_id mcp251x_of_match[] = { 1261 { 1262 .compatible = "microchip,mcp2510", 1263 .data = (void *)CAN_MCP251X_MCP2510, 1264 }, 1265 { 1266 .compatible = "microchip,mcp2515", 1267 .data = (void *)CAN_MCP251X_MCP2515, 1268 }, 1269 { 1270 .compatible = "microchip,mcp25625", 1271 .data = (void *)CAN_MCP251X_MCP25625, 1272 }, 1273 { } 1274 }; 1275 MODULE_DEVICE_TABLE(of, mcp251x_of_match); 1276 1277 static const struct spi_device_id mcp251x_id_table[] = { 1278 { 1279 .name = "mcp2510", 1280 .driver_data = (kernel_ulong_t)CAN_MCP251X_MCP2510, 1281 }, 1282 { 1283 .name = "mcp2515", 1284 .driver_data = (kernel_ulong_t)CAN_MCP251X_MCP2515, 1285 }, 1286 { 1287 .name = "mcp25625", 1288 .driver_data = (kernel_ulong_t)CAN_MCP251X_MCP25625, 1289 }, 1290 { } 1291 }; 1292 MODULE_DEVICE_TABLE(spi, mcp251x_id_table); 1293 1294 static int mcp251x_can_probe(struct spi_device *spi) 1295 { 1296 const void *match = device_get_match_data(&spi->dev); 1297 struct net_device *net; 1298 struct mcp251x_priv *priv; 1299 struct clk *clk; 1300 u32 freq; 1301 int ret; 1302 1303 clk = devm_clk_get_optional(&spi->dev, NULL); 1304 if (IS_ERR(clk)) 1305 return PTR_ERR(clk); 1306 1307 freq = clk_get_rate(clk); 1308 if (freq == 0) 1309 device_property_read_u32(&spi->dev, "clock-frequency", &freq); 1310 1311 /* Sanity check */ 1312 if (freq < 1000000 || freq > 25000000) 1313 return -ERANGE; 1314 1315 /* Allocate can/net device */ 1316 net = alloc_candev(sizeof(struct mcp251x_priv), TX_ECHO_SKB_MAX); 1317 if (!net) 1318 return -ENOMEM; 1319 1320 ret = clk_prepare_enable(clk); 1321 if (ret) 1322 goto out_free; 1323 1324 net->netdev_ops = &mcp251x_netdev_ops; 1325 net->flags |= IFF_ECHO; 1326 1327 priv = netdev_priv(net); 1328 priv->can.bittiming_const = &mcp251x_bittiming_const; 1329 priv->can.do_set_mode = mcp251x_do_set_mode; 1330 priv->can.clock.freq = freq / 2; 1331 priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES | 1332 CAN_CTRLMODE_LOOPBACK | CAN_CTRLMODE_LISTENONLY; 1333 if (match) 1334 priv->model = (enum mcp251x_model)match; 1335 else 1336 priv->model = spi_get_device_id(spi)->driver_data; 1337 priv->net = net; 1338 priv->clk = clk; 1339 1340 spi_set_drvdata(spi, priv); 1341 1342 /* Configure the SPI bus */ 1343 spi->bits_per_word = 8; 1344 if (mcp251x_is_2510(spi)) 1345 spi->max_speed_hz = spi->max_speed_hz ? : 5 * 1000 * 1000; 1346 else 1347 spi->max_speed_hz = spi->max_speed_hz ? : 10 * 1000 * 1000; 1348 ret = spi_setup(spi); 1349 if (ret) 1350 goto out_clk; 1351 1352 priv->power = devm_regulator_get_optional(&spi->dev, "vdd"); 1353 priv->transceiver = devm_regulator_get_optional(&spi->dev, "xceiver"); 1354 if ((PTR_ERR(priv->power) == -EPROBE_DEFER) || 1355 (PTR_ERR(priv->transceiver) == -EPROBE_DEFER)) { 1356 ret = -EPROBE_DEFER; 1357 goto out_clk; 1358 } 1359 1360 ret = mcp251x_power_enable(priv->power, 1); 1361 if (ret) 1362 goto out_clk; 1363 1364 priv->spi = spi; 1365 mutex_init(&priv->mcp_lock); 1366 1367 priv->spi_tx_buf = devm_kzalloc(&spi->dev, SPI_TRANSFER_BUF_LEN, 1368 GFP_KERNEL); 1369 if (!priv->spi_tx_buf) { 1370 ret = -ENOMEM; 1371 goto error_probe; 1372 } 1373 1374 priv->spi_rx_buf = devm_kzalloc(&spi->dev, SPI_TRANSFER_BUF_LEN, 1375 GFP_KERNEL); 1376 if (!priv->spi_rx_buf) { 1377 ret = -ENOMEM; 1378 goto error_probe; 1379 } 1380 1381 SET_NETDEV_DEV(net, &spi->dev); 1382 1383 /* Here is OK to not lock the MCP, no one knows about it yet */ 1384 ret = mcp251x_hw_probe(spi); 1385 if (ret) { 1386 if (ret == -ENODEV) 1387 dev_err(&spi->dev, "Cannot initialize MCP%x. Wrong wiring?\n", 1388 priv->model); 1389 goto error_probe; 1390 } 1391 1392 mcp251x_hw_sleep(spi); 1393 1394 ret = register_candev(net); 1395 if (ret) 1396 goto error_probe; 1397 1398 devm_can_led_init(net); 1399 1400 ret = mcp251x_gpio_setup(priv); 1401 if (ret) 1402 goto error_probe; 1403 1404 netdev_info(net, "MCP%x successfully initialized.\n", priv->model); 1405 return 0; 1406 1407 error_probe: 1408 mcp251x_power_enable(priv->power, 0); 1409 1410 out_clk: 1411 clk_disable_unprepare(clk); 1412 1413 out_free: 1414 free_candev(net); 1415 1416 dev_err(&spi->dev, "Probe failed, err=%d\n", -ret); 1417 return ret; 1418 } 1419 1420 static int mcp251x_can_remove(struct spi_device *spi) 1421 { 1422 struct mcp251x_priv *priv = spi_get_drvdata(spi); 1423 struct net_device *net = priv->net; 1424 1425 unregister_candev(net); 1426 1427 mcp251x_power_enable(priv->power, 0); 1428 1429 clk_disable_unprepare(priv->clk); 1430 1431 free_candev(net); 1432 1433 return 0; 1434 } 1435 1436 static int __maybe_unused mcp251x_can_suspend(struct device *dev) 1437 { 1438 struct spi_device *spi = to_spi_device(dev); 1439 struct mcp251x_priv *priv = spi_get_drvdata(spi); 1440 struct net_device *net = priv->net; 1441 1442 priv->force_quit = 1; 1443 disable_irq(spi->irq); 1444 /* Note: at this point neither IST nor workqueues are running. 1445 * open/stop cannot be called anyway so locking is not needed 1446 */ 1447 if (netif_running(net)) { 1448 netif_device_detach(net); 1449 1450 mcp251x_hw_sleep(spi); 1451 mcp251x_power_enable(priv->transceiver, 0); 1452 priv->after_suspend = AFTER_SUSPEND_UP; 1453 } else { 1454 priv->after_suspend = AFTER_SUSPEND_DOWN; 1455 } 1456 1457 mcp251x_power_enable(priv->power, 0); 1458 priv->after_suspend |= AFTER_SUSPEND_POWER; 1459 1460 return 0; 1461 } 1462 1463 static int __maybe_unused mcp251x_can_resume(struct device *dev) 1464 { 1465 struct spi_device *spi = to_spi_device(dev); 1466 struct mcp251x_priv *priv = spi_get_drvdata(spi); 1467 1468 if (priv->after_suspend & AFTER_SUSPEND_POWER) 1469 mcp251x_power_enable(priv->power, 1); 1470 if (priv->after_suspend & AFTER_SUSPEND_UP) 1471 mcp251x_power_enable(priv->transceiver, 1); 1472 1473 if (priv->after_suspend & (AFTER_SUSPEND_POWER | AFTER_SUSPEND_UP)) 1474 queue_work(priv->wq, &priv->restart_work); 1475 else 1476 priv->after_suspend = 0; 1477 1478 priv->force_quit = 0; 1479 enable_irq(spi->irq); 1480 return 0; 1481 } 1482 1483 static SIMPLE_DEV_PM_OPS(mcp251x_can_pm_ops, mcp251x_can_suspend, 1484 mcp251x_can_resume); 1485 1486 static struct spi_driver mcp251x_can_driver = { 1487 .driver = { 1488 .name = DEVICE_NAME, 1489 .of_match_table = mcp251x_of_match, 1490 .pm = &mcp251x_can_pm_ops, 1491 }, 1492 .id_table = mcp251x_id_table, 1493 .probe = mcp251x_can_probe, 1494 .remove = mcp251x_can_remove, 1495 }; 1496 module_spi_driver(mcp251x_can_driver); 1497 1498 MODULE_AUTHOR("Chris Elston <celston@katalix.com>, " 1499 "Christian Pellegrin <chripell@evolware.org>"); 1500 MODULE_DESCRIPTION("Microchip 251x/25625 CAN driver"); 1501 MODULE_LICENSE("GPL v2"); 1502