1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Maxim (Dallas) MAX3107/8/9, MAX14830 serial driver 4 * 5 * Copyright (C) 2012-2016 Alexander Shiyan <shc_work@mail.ru> 6 * 7 * Based on max3100.c, by Christian Pellegrin <chripell@evolware.org> 8 * Based on max3110.c, by Feng Tang <feng.tang@intel.com> 9 * Based on max3107.c, by Aavamobile 10 */ 11 12 #include <linux/bitops.h> 13 #include <linux/clk.h> 14 #include <linux/delay.h> 15 #include <linux/device.h> 16 #include <linux/gpio/driver.h> 17 #include <linux/module.h> 18 #include <linux/of.h> 19 #include <linux/of_device.h> 20 #include <linux/regmap.h> 21 #include <linux/serial_core.h> 22 #include <linux/serial.h> 23 #include <linux/tty.h> 24 #include <linux/tty_flip.h> 25 #include <linux/spi/spi.h> 26 #include <linux/uaccess.h> 27 28 #define MAX310X_NAME "max310x" 29 #define MAX310X_MAJOR 204 30 #define MAX310X_MINOR 209 31 #define MAX310X_UART_NRMAX 16 32 33 /* MAX310X register definitions */ 34 #define MAX310X_RHR_REG (0x00) /* RX FIFO */ 35 #define MAX310X_THR_REG (0x00) /* TX FIFO */ 36 #define MAX310X_IRQEN_REG (0x01) /* IRQ enable */ 37 #define MAX310X_IRQSTS_REG (0x02) /* IRQ status */ 38 #define MAX310X_LSR_IRQEN_REG (0x03) /* LSR IRQ enable */ 39 #define MAX310X_LSR_IRQSTS_REG (0x04) /* LSR IRQ status */ 40 #define MAX310X_REG_05 (0x05) 41 #define MAX310X_SPCHR_IRQEN_REG MAX310X_REG_05 /* Special char IRQ en */ 42 #define MAX310X_SPCHR_IRQSTS_REG (0x06) /* Special char IRQ status */ 43 #define MAX310X_STS_IRQEN_REG (0x07) /* Status IRQ enable */ 44 #define MAX310X_STS_IRQSTS_REG (0x08) /* Status IRQ status */ 45 #define MAX310X_MODE1_REG (0x09) /* MODE1 */ 46 #define MAX310X_MODE2_REG (0x0a) /* MODE2 */ 47 #define MAX310X_LCR_REG (0x0b) /* LCR */ 48 #define MAX310X_RXTO_REG (0x0c) /* RX timeout */ 49 #define MAX310X_HDPIXDELAY_REG (0x0d) /* Auto transceiver delays */ 50 #define MAX310X_IRDA_REG (0x0e) /* IRDA settings */ 51 #define MAX310X_FLOWLVL_REG (0x0f) /* Flow control levels */ 52 #define MAX310X_FIFOTRIGLVL_REG (0x10) /* FIFO IRQ trigger levels */ 53 #define MAX310X_TXFIFOLVL_REG (0x11) /* TX FIFO level */ 54 #define MAX310X_RXFIFOLVL_REG (0x12) /* RX FIFO level */ 55 #define MAX310X_FLOWCTRL_REG (0x13) /* Flow control */ 56 #define MAX310X_XON1_REG (0x14) /* XON1 character */ 57 #define MAX310X_XON2_REG (0x15) /* XON2 character */ 58 #define MAX310X_XOFF1_REG (0x16) /* XOFF1 character */ 59 #define MAX310X_XOFF2_REG (0x17) /* XOFF2 character */ 60 #define MAX310X_GPIOCFG_REG (0x18) /* GPIO config */ 61 #define MAX310X_GPIODATA_REG (0x19) /* GPIO data */ 62 #define MAX310X_PLLCFG_REG (0x1a) /* PLL config */ 63 #define MAX310X_BRGCFG_REG (0x1b) /* Baud rate generator conf */ 64 #define MAX310X_BRGDIVLSB_REG (0x1c) /* Baud rate divisor LSB */ 65 #define MAX310X_BRGDIVMSB_REG (0x1d) /* Baud rate divisor MSB */ 66 #define MAX310X_CLKSRC_REG (0x1e) /* Clock source */ 67 #define MAX310X_REG_1F (0x1f) 68 69 #define MAX310X_REVID_REG MAX310X_REG_1F /* Revision ID */ 70 71 #define MAX310X_GLOBALIRQ_REG MAX310X_REG_1F /* Global IRQ (RO) */ 72 #define MAX310X_GLOBALCMD_REG MAX310X_REG_1F /* Global Command (WO) */ 73 74 /* Extended registers */ 75 #define MAX310X_REVID_EXTREG MAX310X_REG_05 /* Revision ID */ 76 77 /* IRQ register bits */ 78 #define MAX310X_IRQ_LSR_BIT (1 << 0) /* LSR interrupt */ 79 #define MAX310X_IRQ_SPCHR_BIT (1 << 1) /* Special char interrupt */ 80 #define MAX310X_IRQ_STS_BIT (1 << 2) /* Status interrupt */ 81 #define MAX310X_IRQ_RXFIFO_BIT (1 << 3) /* RX FIFO interrupt */ 82 #define MAX310X_IRQ_TXFIFO_BIT (1 << 4) /* TX FIFO interrupt */ 83 #define MAX310X_IRQ_TXEMPTY_BIT (1 << 5) /* TX FIFO empty interrupt */ 84 #define MAX310X_IRQ_RXEMPTY_BIT (1 << 6) /* RX FIFO empty interrupt */ 85 #define MAX310X_IRQ_CTS_BIT (1 << 7) /* CTS interrupt */ 86 87 /* LSR register bits */ 88 #define MAX310X_LSR_RXTO_BIT (1 << 0) /* RX timeout */ 89 #define MAX310X_LSR_RXOVR_BIT (1 << 1) /* RX overrun */ 90 #define MAX310X_LSR_RXPAR_BIT (1 << 2) /* RX parity error */ 91 #define MAX310X_LSR_FRERR_BIT (1 << 3) /* Frame error */ 92 #define MAX310X_LSR_RXBRK_BIT (1 << 4) /* RX break */ 93 #define MAX310X_LSR_RXNOISE_BIT (1 << 5) /* RX noise */ 94 #define MAX310X_LSR_CTS_BIT (1 << 7) /* CTS pin state */ 95 96 /* Special character register bits */ 97 #define MAX310X_SPCHR_XON1_BIT (1 << 0) /* XON1 character */ 98 #define MAX310X_SPCHR_XON2_BIT (1 << 1) /* XON2 character */ 99 #define MAX310X_SPCHR_XOFF1_BIT (1 << 2) /* XOFF1 character */ 100 #define MAX310X_SPCHR_XOFF2_BIT (1 << 3) /* XOFF2 character */ 101 #define MAX310X_SPCHR_BREAK_BIT (1 << 4) /* RX break */ 102 #define MAX310X_SPCHR_MULTIDROP_BIT (1 << 5) /* 9-bit multidrop addr char */ 103 104 /* Status register bits */ 105 #define MAX310X_STS_GPIO0_BIT (1 << 0) /* GPIO 0 interrupt */ 106 #define MAX310X_STS_GPIO1_BIT (1 << 1) /* GPIO 1 interrupt */ 107 #define MAX310X_STS_GPIO2_BIT (1 << 2) /* GPIO 2 interrupt */ 108 #define MAX310X_STS_GPIO3_BIT (1 << 3) /* GPIO 3 interrupt */ 109 #define MAX310X_STS_CLKREADY_BIT (1 << 5) /* Clock ready */ 110 #define MAX310X_STS_SLEEP_BIT (1 << 6) /* Sleep interrupt */ 111 112 /* MODE1 register bits */ 113 #define MAX310X_MODE1_RXDIS_BIT (1 << 0) /* RX disable */ 114 #define MAX310X_MODE1_TXDIS_BIT (1 << 1) /* TX disable */ 115 #define MAX310X_MODE1_TXHIZ_BIT (1 << 2) /* TX pin three-state */ 116 #define MAX310X_MODE1_RTSHIZ_BIT (1 << 3) /* RTS pin three-state */ 117 #define MAX310X_MODE1_TRNSCVCTRL_BIT (1 << 4) /* Transceiver ctrl enable */ 118 #define MAX310X_MODE1_FORCESLEEP_BIT (1 << 5) /* Force sleep mode */ 119 #define MAX310X_MODE1_AUTOSLEEP_BIT (1 << 6) /* Auto sleep enable */ 120 #define MAX310X_MODE1_IRQSEL_BIT (1 << 7) /* IRQ pin enable */ 121 122 /* MODE2 register bits */ 123 #define MAX310X_MODE2_RST_BIT (1 << 0) /* Chip reset */ 124 #define MAX310X_MODE2_FIFORST_BIT (1 << 1) /* FIFO reset */ 125 #define MAX310X_MODE2_RXTRIGINV_BIT (1 << 2) /* RX FIFO INT invert */ 126 #define MAX310X_MODE2_RXEMPTINV_BIT (1 << 3) /* RX FIFO empty INT invert */ 127 #define MAX310X_MODE2_SPCHR_BIT (1 << 4) /* Special chr detect enable */ 128 #define MAX310X_MODE2_LOOPBACK_BIT (1 << 5) /* Internal loopback enable */ 129 #define MAX310X_MODE2_MULTIDROP_BIT (1 << 6) /* 9-bit multidrop enable */ 130 #define MAX310X_MODE2_ECHOSUPR_BIT (1 << 7) /* ECHO suppression enable */ 131 132 /* LCR register bits */ 133 #define MAX310X_LCR_LENGTH0_BIT (1 << 0) /* Word length bit 0 */ 134 #define MAX310X_LCR_LENGTH1_BIT (1 << 1) /* Word length bit 1 135 * 136 * Word length bits table: 137 * 00 -> 5 bit words 138 * 01 -> 6 bit words 139 * 10 -> 7 bit words 140 * 11 -> 8 bit words 141 */ 142 #define MAX310X_LCR_STOPLEN_BIT (1 << 2) /* STOP length bit 143 * 144 * STOP length bit table: 145 * 0 -> 1 stop bit 146 * 1 -> 1-1.5 stop bits if 147 * word length is 5, 148 * 2 stop bits otherwise 149 */ 150 #define MAX310X_LCR_PARITY_BIT (1 << 3) /* Parity bit enable */ 151 #define MAX310X_LCR_EVENPARITY_BIT (1 << 4) /* Even parity bit enable */ 152 #define MAX310X_LCR_FORCEPARITY_BIT (1 << 5) /* 9-bit multidrop parity */ 153 #define MAX310X_LCR_TXBREAK_BIT (1 << 6) /* TX break enable */ 154 #define MAX310X_LCR_RTS_BIT (1 << 7) /* RTS pin control */ 155 156 /* IRDA register bits */ 157 #define MAX310X_IRDA_IRDAEN_BIT (1 << 0) /* IRDA mode enable */ 158 #define MAX310X_IRDA_SIR_BIT (1 << 1) /* SIR mode enable */ 159 160 /* Flow control trigger level register masks */ 161 #define MAX310X_FLOWLVL_HALT_MASK (0x000f) /* Flow control halt level */ 162 #define MAX310X_FLOWLVL_RES_MASK (0x00f0) /* Flow control resume level */ 163 #define MAX310X_FLOWLVL_HALT(words) ((words / 8) & 0x0f) 164 #define MAX310X_FLOWLVL_RES(words) (((words / 8) & 0x0f) << 4) 165 166 /* FIFO interrupt trigger level register masks */ 167 #define MAX310X_FIFOTRIGLVL_TX_MASK (0x0f) /* TX FIFO trigger level */ 168 #define MAX310X_FIFOTRIGLVL_RX_MASK (0xf0) /* RX FIFO trigger level */ 169 #define MAX310X_FIFOTRIGLVL_TX(words) ((words / 8) & 0x0f) 170 #define MAX310X_FIFOTRIGLVL_RX(words) (((words / 8) & 0x0f) << 4) 171 172 /* Flow control register bits */ 173 #define MAX310X_FLOWCTRL_AUTORTS_BIT (1 << 0) /* Auto RTS flow ctrl enable */ 174 #define MAX310X_FLOWCTRL_AUTOCTS_BIT (1 << 1) /* Auto CTS flow ctrl enable */ 175 #define MAX310X_FLOWCTRL_GPIADDR_BIT (1 << 2) /* Enables that GPIO inputs 176 * are used in conjunction with 177 * XOFF2 for definition of 178 * special character */ 179 #define MAX310X_FLOWCTRL_SWFLOWEN_BIT (1 << 3) /* Auto SW flow ctrl enable */ 180 #define MAX310X_FLOWCTRL_SWFLOW0_BIT (1 << 4) /* SWFLOW bit 0 */ 181 #define MAX310X_FLOWCTRL_SWFLOW1_BIT (1 << 5) /* SWFLOW bit 1 182 * 183 * SWFLOW bits 1 & 0 table: 184 * 00 -> no transmitter flow 185 * control 186 * 01 -> receiver compares 187 * XON2 and XOFF2 188 * and controls 189 * transmitter 190 * 10 -> receiver compares 191 * XON1 and XOFF1 192 * and controls 193 * transmitter 194 * 11 -> receiver compares 195 * XON1, XON2, XOFF1 and 196 * XOFF2 and controls 197 * transmitter 198 */ 199 #define MAX310X_FLOWCTRL_SWFLOW2_BIT (1 << 6) /* SWFLOW bit 2 */ 200 #define MAX310X_FLOWCTRL_SWFLOW3_BIT (1 << 7) /* SWFLOW bit 3 201 * 202 * SWFLOW bits 3 & 2 table: 203 * 00 -> no received flow 204 * control 205 * 01 -> transmitter generates 206 * XON2 and XOFF2 207 * 10 -> transmitter generates 208 * XON1 and XOFF1 209 * 11 -> transmitter generates 210 * XON1, XON2, XOFF1 and 211 * XOFF2 212 */ 213 214 /* PLL configuration register masks */ 215 #define MAX310X_PLLCFG_PREDIV_MASK (0x3f) /* PLL predivision value */ 216 #define MAX310X_PLLCFG_PLLFACTOR_MASK (0xc0) /* PLL multiplication factor */ 217 218 /* Baud rate generator configuration register bits */ 219 #define MAX310X_BRGCFG_2XMODE_BIT (1 << 4) /* Double baud rate */ 220 #define MAX310X_BRGCFG_4XMODE_BIT (1 << 5) /* Quadruple baud rate */ 221 222 /* Clock source register bits */ 223 #define MAX310X_CLKSRC_CRYST_BIT (1 << 1) /* Crystal osc enable */ 224 #define MAX310X_CLKSRC_PLL_BIT (1 << 2) /* PLL enable */ 225 #define MAX310X_CLKSRC_PLLBYP_BIT (1 << 3) /* PLL bypass */ 226 #define MAX310X_CLKSRC_EXTCLK_BIT (1 << 4) /* External clock enable */ 227 #define MAX310X_CLKSRC_CLK2RTS_BIT (1 << 7) /* Baud clk to RTS pin */ 228 229 /* Global commands */ 230 #define MAX310X_EXTREG_ENBL (0xce) 231 #define MAX310X_EXTREG_DSBL (0xcd) 232 233 /* Misc definitions */ 234 #define MAX310X_FIFO_SIZE (128) 235 #define MAX310x_REV_MASK (0xf8) 236 #define MAX310X_WRITE_BIT 0x80 237 238 /* MAX3107 specific */ 239 #define MAX3107_REV_ID (0xa0) 240 241 /* MAX3109 specific */ 242 #define MAX3109_REV_ID (0xc0) 243 244 /* MAX14830 specific */ 245 #define MAX14830_BRGCFG_CLKDIS_BIT (1 << 6) /* Clock Disable */ 246 #define MAX14830_REV_ID (0xb0) 247 248 struct max310x_devtype { 249 char name[9]; 250 int nr; 251 u8 mode1; 252 int (*detect)(struct device *); 253 void (*power)(struct uart_port *, int); 254 }; 255 256 struct max310x_one { 257 struct uart_port port; 258 struct work_struct tx_work; 259 struct work_struct md_work; 260 struct work_struct rs_work; 261 262 u8 wr_header; 263 u8 rd_header; 264 u8 rx_buf[MAX310X_FIFO_SIZE]; 265 }; 266 #define to_max310x_port(_port) \ 267 container_of(_port, struct max310x_one, port) 268 269 struct max310x_port { 270 struct max310x_devtype *devtype; 271 struct regmap *regmap; 272 struct clk *clk; 273 #ifdef CONFIG_GPIOLIB 274 struct gpio_chip gpio; 275 #endif 276 struct max310x_one p[0]; 277 }; 278 279 static struct uart_driver max310x_uart = { 280 .owner = THIS_MODULE, 281 .driver_name = MAX310X_NAME, 282 .dev_name = "ttyMAX", 283 .major = MAX310X_MAJOR, 284 .minor = MAX310X_MINOR, 285 .nr = MAX310X_UART_NRMAX, 286 }; 287 288 static DECLARE_BITMAP(max310x_lines, MAX310X_UART_NRMAX); 289 290 static u8 max310x_port_read(struct uart_port *port, u8 reg) 291 { 292 struct max310x_port *s = dev_get_drvdata(port->dev); 293 unsigned int val = 0; 294 295 regmap_read(s->regmap, port->iobase + reg, &val); 296 297 return val; 298 } 299 300 static void max310x_port_write(struct uart_port *port, u8 reg, u8 val) 301 { 302 struct max310x_port *s = dev_get_drvdata(port->dev); 303 304 regmap_write(s->regmap, port->iobase + reg, val); 305 } 306 307 static void max310x_port_update(struct uart_port *port, u8 reg, u8 mask, u8 val) 308 { 309 struct max310x_port *s = dev_get_drvdata(port->dev); 310 311 regmap_update_bits(s->regmap, port->iobase + reg, mask, val); 312 } 313 314 static int max3107_detect(struct device *dev) 315 { 316 struct max310x_port *s = dev_get_drvdata(dev); 317 unsigned int val = 0; 318 int ret; 319 320 ret = regmap_read(s->regmap, MAX310X_REVID_REG, &val); 321 if (ret) 322 return ret; 323 324 if (((val & MAX310x_REV_MASK) != MAX3107_REV_ID)) { 325 dev_err(dev, 326 "%s ID 0x%02x does not match\n", s->devtype->name, val); 327 return -ENODEV; 328 } 329 330 return 0; 331 } 332 333 static int max3108_detect(struct device *dev) 334 { 335 struct max310x_port *s = dev_get_drvdata(dev); 336 unsigned int val = 0; 337 int ret; 338 339 /* MAX3108 have not REV ID register, we just check default value 340 * from clocksource register to make sure everything works. 341 */ 342 ret = regmap_read(s->regmap, MAX310X_CLKSRC_REG, &val); 343 if (ret) 344 return ret; 345 346 if (val != (MAX310X_CLKSRC_EXTCLK_BIT | MAX310X_CLKSRC_PLLBYP_BIT)) { 347 dev_err(dev, "%s not present\n", s->devtype->name); 348 return -ENODEV; 349 } 350 351 return 0; 352 } 353 354 static int max3109_detect(struct device *dev) 355 { 356 struct max310x_port *s = dev_get_drvdata(dev); 357 unsigned int val = 0; 358 int ret; 359 360 ret = regmap_write(s->regmap, MAX310X_GLOBALCMD_REG, 361 MAX310X_EXTREG_ENBL); 362 if (ret) 363 return ret; 364 365 regmap_read(s->regmap, MAX310X_REVID_EXTREG, &val); 366 regmap_write(s->regmap, MAX310X_GLOBALCMD_REG, MAX310X_EXTREG_DSBL); 367 if (((val & MAX310x_REV_MASK) != MAX3109_REV_ID)) { 368 dev_err(dev, 369 "%s ID 0x%02x does not match\n", s->devtype->name, val); 370 return -ENODEV; 371 } 372 373 return 0; 374 } 375 376 static void max310x_power(struct uart_port *port, int on) 377 { 378 max310x_port_update(port, MAX310X_MODE1_REG, 379 MAX310X_MODE1_FORCESLEEP_BIT, 380 on ? 0 : MAX310X_MODE1_FORCESLEEP_BIT); 381 if (on) 382 msleep(50); 383 } 384 385 static int max14830_detect(struct device *dev) 386 { 387 struct max310x_port *s = dev_get_drvdata(dev); 388 unsigned int val = 0; 389 int ret; 390 391 ret = regmap_write(s->regmap, MAX310X_GLOBALCMD_REG, 392 MAX310X_EXTREG_ENBL); 393 if (ret) 394 return ret; 395 396 regmap_read(s->regmap, MAX310X_REVID_EXTREG, &val); 397 regmap_write(s->regmap, MAX310X_GLOBALCMD_REG, MAX310X_EXTREG_DSBL); 398 if (((val & MAX310x_REV_MASK) != MAX14830_REV_ID)) { 399 dev_err(dev, 400 "%s ID 0x%02x does not match\n", s->devtype->name, val); 401 return -ENODEV; 402 } 403 404 return 0; 405 } 406 407 static void max14830_power(struct uart_port *port, int on) 408 { 409 max310x_port_update(port, MAX310X_BRGCFG_REG, 410 MAX14830_BRGCFG_CLKDIS_BIT, 411 on ? 0 : MAX14830_BRGCFG_CLKDIS_BIT); 412 if (on) 413 msleep(50); 414 } 415 416 static const struct max310x_devtype max3107_devtype = { 417 .name = "MAX3107", 418 .nr = 1, 419 .mode1 = MAX310X_MODE1_AUTOSLEEP_BIT | MAX310X_MODE1_IRQSEL_BIT, 420 .detect = max3107_detect, 421 .power = max310x_power, 422 }; 423 424 static const struct max310x_devtype max3108_devtype = { 425 .name = "MAX3108", 426 .nr = 1, 427 .mode1 = MAX310X_MODE1_AUTOSLEEP_BIT, 428 .detect = max3108_detect, 429 .power = max310x_power, 430 }; 431 432 static const struct max310x_devtype max3109_devtype = { 433 .name = "MAX3109", 434 .nr = 2, 435 .mode1 = MAX310X_MODE1_AUTOSLEEP_BIT, 436 .detect = max3109_detect, 437 .power = max310x_power, 438 }; 439 440 static const struct max310x_devtype max14830_devtype = { 441 .name = "MAX14830", 442 .nr = 4, 443 .mode1 = MAX310X_MODE1_IRQSEL_BIT, 444 .detect = max14830_detect, 445 .power = max14830_power, 446 }; 447 448 static bool max310x_reg_writeable(struct device *dev, unsigned int reg) 449 { 450 switch (reg & 0x1f) { 451 case MAX310X_IRQSTS_REG: 452 case MAX310X_LSR_IRQSTS_REG: 453 case MAX310X_SPCHR_IRQSTS_REG: 454 case MAX310X_STS_IRQSTS_REG: 455 case MAX310X_TXFIFOLVL_REG: 456 case MAX310X_RXFIFOLVL_REG: 457 return false; 458 default: 459 break; 460 } 461 462 return true; 463 } 464 465 static bool max310x_reg_volatile(struct device *dev, unsigned int reg) 466 { 467 switch (reg & 0x1f) { 468 case MAX310X_RHR_REG: 469 case MAX310X_IRQSTS_REG: 470 case MAX310X_LSR_IRQSTS_REG: 471 case MAX310X_SPCHR_IRQSTS_REG: 472 case MAX310X_STS_IRQSTS_REG: 473 case MAX310X_TXFIFOLVL_REG: 474 case MAX310X_RXFIFOLVL_REG: 475 case MAX310X_GPIODATA_REG: 476 case MAX310X_BRGDIVLSB_REG: 477 case MAX310X_REG_05: 478 case MAX310X_REG_1F: 479 return true; 480 default: 481 break; 482 } 483 484 return false; 485 } 486 487 static bool max310x_reg_precious(struct device *dev, unsigned int reg) 488 { 489 switch (reg & 0x1f) { 490 case MAX310X_RHR_REG: 491 case MAX310X_IRQSTS_REG: 492 case MAX310X_SPCHR_IRQSTS_REG: 493 case MAX310X_STS_IRQSTS_REG: 494 return true; 495 default: 496 break; 497 } 498 499 return false; 500 } 501 502 static int max310x_set_baud(struct uart_port *port, int baud) 503 { 504 unsigned int mode = 0, div = 0, frac = 0, c = 0, F = 0; 505 506 /* 507 * Calculate the integer divisor first. Select a proper mode 508 * in case if the requested baud is too high for the pre-defined 509 * clocks frequency. 510 */ 511 div = port->uartclk / baud; 512 if (div < 8) { 513 /* Mode x4 */ 514 c = 4; 515 mode = MAX310X_BRGCFG_4XMODE_BIT; 516 } else if (div < 16) { 517 /* Mode x2 */ 518 c = 8; 519 mode = MAX310X_BRGCFG_2XMODE_BIT; 520 } else { 521 c = 16; 522 } 523 524 /* Calculate the divisor in accordance with the fraction coefficient */ 525 div /= c; 526 F = c*baud; 527 528 /* Calculate the baud rate fraction */ 529 if (div > 0) 530 frac = (16*(port->uartclk % F)) / F; 531 else 532 div = 1; 533 534 max310x_port_write(port, MAX310X_BRGDIVMSB_REG, div >> 8); 535 max310x_port_write(port, MAX310X_BRGDIVLSB_REG, div); 536 max310x_port_write(port, MAX310X_BRGCFG_REG, frac | mode); 537 538 /* Return the actual baud rate we just programmed */ 539 return (16*port->uartclk) / (c*(16*div + frac)); 540 } 541 542 static int max310x_update_best_err(unsigned long f, long *besterr) 543 { 544 /* Use baudrate 115200 for calculate error */ 545 long err = f % (460800 * 16); 546 547 if ((*besterr < 0) || (*besterr > err)) { 548 *besterr = err; 549 return 0; 550 } 551 552 return 1; 553 } 554 555 static int max310x_set_ref_clk(struct device *dev, struct max310x_port *s, 556 unsigned long freq, bool xtal) 557 { 558 unsigned int div, clksrc, pllcfg = 0; 559 long besterr = -1; 560 unsigned long fdiv, fmul, bestfreq = freq; 561 562 /* First, update error without PLL */ 563 max310x_update_best_err(freq, &besterr); 564 565 /* Try all possible PLL dividers */ 566 for (div = 1; (div <= 63) && besterr; div++) { 567 fdiv = DIV_ROUND_CLOSEST(freq, div); 568 569 /* Try multiplier 6 */ 570 fmul = fdiv * 6; 571 if ((fdiv >= 500000) && (fdiv <= 800000)) 572 if (!max310x_update_best_err(fmul, &besterr)) { 573 pllcfg = (0 << 6) | div; 574 bestfreq = fmul; 575 } 576 /* Try multiplier 48 */ 577 fmul = fdiv * 48; 578 if ((fdiv >= 850000) && (fdiv <= 1200000)) 579 if (!max310x_update_best_err(fmul, &besterr)) { 580 pllcfg = (1 << 6) | div; 581 bestfreq = fmul; 582 } 583 /* Try multiplier 96 */ 584 fmul = fdiv * 96; 585 if ((fdiv >= 425000) && (fdiv <= 1000000)) 586 if (!max310x_update_best_err(fmul, &besterr)) { 587 pllcfg = (2 << 6) | div; 588 bestfreq = fmul; 589 } 590 /* Try multiplier 144 */ 591 fmul = fdiv * 144; 592 if ((fdiv >= 390000) && (fdiv <= 667000)) 593 if (!max310x_update_best_err(fmul, &besterr)) { 594 pllcfg = (3 << 6) | div; 595 bestfreq = fmul; 596 } 597 } 598 599 /* Configure clock source */ 600 clksrc = MAX310X_CLKSRC_EXTCLK_BIT | (xtal ? MAX310X_CLKSRC_CRYST_BIT : 0); 601 602 /* Configure PLL */ 603 if (pllcfg) { 604 clksrc |= MAX310X_CLKSRC_PLL_BIT; 605 regmap_write(s->regmap, MAX310X_PLLCFG_REG, pllcfg); 606 } else 607 clksrc |= MAX310X_CLKSRC_PLLBYP_BIT; 608 609 regmap_write(s->regmap, MAX310X_CLKSRC_REG, clksrc); 610 611 /* Wait for crystal */ 612 if (xtal) { 613 unsigned int val; 614 msleep(10); 615 regmap_read(s->regmap, MAX310X_STS_IRQSTS_REG, &val); 616 if (!(val & MAX310X_STS_CLKREADY_BIT)) { 617 dev_warn(dev, "clock is not stable yet\n"); 618 } 619 } 620 621 return (int)bestfreq; 622 } 623 624 static void max310x_batch_write(struct uart_port *port, u8 *txbuf, unsigned int len) 625 { 626 struct max310x_one *one = to_max310x_port(port); 627 struct spi_transfer xfer[] = { 628 { 629 .tx_buf = &one->wr_header, 630 .len = sizeof(one->wr_header), 631 }, { 632 .tx_buf = txbuf, 633 .len = len, 634 } 635 }; 636 spi_sync_transfer(to_spi_device(port->dev), xfer, ARRAY_SIZE(xfer)); 637 } 638 639 static void max310x_batch_read(struct uart_port *port, u8 *rxbuf, unsigned int len) 640 { 641 struct max310x_one *one = to_max310x_port(port); 642 struct spi_transfer xfer[] = { 643 { 644 .tx_buf = &one->rd_header, 645 .len = sizeof(one->rd_header), 646 }, { 647 .rx_buf = rxbuf, 648 .len = len, 649 } 650 }; 651 spi_sync_transfer(to_spi_device(port->dev), xfer, ARRAY_SIZE(xfer)); 652 } 653 654 static void max310x_handle_rx(struct uart_port *port, unsigned int rxlen) 655 { 656 struct max310x_one *one = to_max310x_port(port); 657 unsigned int sts, ch, flag, i; 658 659 if (port->read_status_mask == MAX310X_LSR_RXOVR_BIT) { 660 /* We are just reading, happily ignoring any error conditions. 661 * Break condition, parity checking, framing errors -- they 662 * are all ignored. That means that we can do a batch-read. 663 * 664 * There is a small opportunity for race if the RX FIFO 665 * overruns while we're reading the buffer; the datasheets says 666 * that the LSR register applies to the "current" character. 667 * That's also the reason why we cannot do batched reads when 668 * asked to check the individual statuses. 669 * */ 670 671 sts = max310x_port_read(port, MAX310X_LSR_IRQSTS_REG); 672 max310x_batch_read(port, one->rx_buf, rxlen); 673 674 port->icount.rx += rxlen; 675 flag = TTY_NORMAL; 676 sts &= port->read_status_mask; 677 678 if (sts & MAX310X_LSR_RXOVR_BIT) { 679 dev_warn_ratelimited(port->dev, "Hardware RX FIFO overrun\n"); 680 port->icount.overrun++; 681 } 682 683 for (i = 0; i < (rxlen - 1); ++i) 684 uart_insert_char(port, sts, 0, one->rx_buf[i], flag); 685 686 /* 687 * Handle the overrun case for the last character only, since 688 * the RxFIFO overflow happens after it is pushed to the FIFO 689 * tail. 690 */ 691 uart_insert_char(port, sts, MAX310X_LSR_RXOVR_BIT, 692 one->rx_buf[rxlen-1], flag); 693 694 } else { 695 if (unlikely(rxlen >= port->fifosize)) { 696 dev_warn_ratelimited(port->dev, "Possible RX FIFO overrun\n"); 697 port->icount.buf_overrun++; 698 /* Ensure sanity of RX level */ 699 rxlen = port->fifosize; 700 } 701 702 while (rxlen--) { 703 ch = max310x_port_read(port, MAX310X_RHR_REG); 704 sts = max310x_port_read(port, MAX310X_LSR_IRQSTS_REG); 705 706 sts &= MAX310X_LSR_RXPAR_BIT | MAX310X_LSR_FRERR_BIT | 707 MAX310X_LSR_RXOVR_BIT | MAX310X_LSR_RXBRK_BIT; 708 709 port->icount.rx++; 710 flag = TTY_NORMAL; 711 712 if (unlikely(sts)) { 713 if (sts & MAX310X_LSR_RXBRK_BIT) { 714 port->icount.brk++; 715 if (uart_handle_break(port)) 716 continue; 717 } else if (sts & MAX310X_LSR_RXPAR_BIT) 718 port->icount.parity++; 719 else if (sts & MAX310X_LSR_FRERR_BIT) 720 port->icount.frame++; 721 else if (sts & MAX310X_LSR_RXOVR_BIT) 722 port->icount.overrun++; 723 724 sts &= port->read_status_mask; 725 if (sts & MAX310X_LSR_RXBRK_BIT) 726 flag = TTY_BREAK; 727 else if (sts & MAX310X_LSR_RXPAR_BIT) 728 flag = TTY_PARITY; 729 else if (sts & MAX310X_LSR_FRERR_BIT) 730 flag = TTY_FRAME; 731 else if (sts & MAX310X_LSR_RXOVR_BIT) 732 flag = TTY_OVERRUN; 733 } 734 735 if (uart_handle_sysrq_char(port, ch)) 736 continue; 737 738 if (sts & port->ignore_status_mask) 739 continue; 740 741 uart_insert_char(port, sts, MAX310X_LSR_RXOVR_BIT, ch, flag); 742 } 743 } 744 745 tty_flip_buffer_push(&port->state->port); 746 } 747 748 static void max310x_handle_tx(struct uart_port *port) 749 { 750 struct circ_buf *xmit = &port->state->xmit; 751 unsigned int txlen, to_send, until_end; 752 753 if (unlikely(port->x_char)) { 754 max310x_port_write(port, MAX310X_THR_REG, port->x_char); 755 port->icount.tx++; 756 port->x_char = 0; 757 return; 758 } 759 760 if (uart_circ_empty(xmit) || uart_tx_stopped(port)) 761 return; 762 763 /* Get length of data pending in circular buffer */ 764 to_send = uart_circ_chars_pending(xmit); 765 until_end = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE); 766 if (likely(to_send)) { 767 /* Limit to size of TX FIFO */ 768 txlen = max310x_port_read(port, MAX310X_TXFIFOLVL_REG); 769 txlen = port->fifosize - txlen; 770 to_send = (to_send > txlen) ? txlen : to_send; 771 772 if (until_end < to_send) { 773 /* It's a circ buffer -- wrap around. 774 * We could do that in one SPI transaction, but meh. */ 775 max310x_batch_write(port, xmit->buf + xmit->tail, until_end); 776 max310x_batch_write(port, xmit->buf, to_send - until_end); 777 } else { 778 max310x_batch_write(port, xmit->buf + xmit->tail, to_send); 779 } 780 781 /* Add data to send */ 782 port->icount.tx += to_send; 783 xmit->tail = (xmit->tail + to_send) & (UART_XMIT_SIZE - 1); 784 } 785 786 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) 787 uart_write_wakeup(port); 788 } 789 790 static void max310x_start_tx(struct uart_port *port) 791 { 792 struct max310x_one *one = to_max310x_port(port); 793 794 schedule_work(&one->tx_work); 795 } 796 797 static irqreturn_t max310x_port_irq(struct max310x_port *s, int portno) 798 { 799 struct uart_port *port = &s->p[portno].port; 800 irqreturn_t res = IRQ_NONE; 801 802 do { 803 unsigned int ists, lsr, rxlen; 804 805 /* Read IRQ status & RX FIFO level */ 806 ists = max310x_port_read(port, MAX310X_IRQSTS_REG); 807 rxlen = max310x_port_read(port, MAX310X_RXFIFOLVL_REG); 808 if (!ists && !rxlen) 809 break; 810 811 res = IRQ_HANDLED; 812 813 if (ists & MAX310X_IRQ_CTS_BIT) { 814 lsr = max310x_port_read(port, MAX310X_LSR_IRQSTS_REG); 815 uart_handle_cts_change(port, 816 !!(lsr & MAX310X_LSR_CTS_BIT)); 817 } 818 if (rxlen) 819 max310x_handle_rx(port, rxlen); 820 if (ists & MAX310X_IRQ_TXEMPTY_BIT) 821 max310x_start_tx(port); 822 } while (1); 823 return res; 824 } 825 826 static irqreturn_t max310x_ist(int irq, void *dev_id) 827 { 828 struct max310x_port *s = (struct max310x_port *)dev_id; 829 bool handled = false; 830 831 if (s->devtype->nr > 1) { 832 do { 833 unsigned int val = ~0; 834 835 WARN_ON_ONCE(regmap_read(s->regmap, 836 MAX310X_GLOBALIRQ_REG, &val)); 837 val = ((1 << s->devtype->nr) - 1) & ~val; 838 if (!val) 839 break; 840 if (max310x_port_irq(s, fls(val) - 1) == IRQ_HANDLED) 841 handled = true; 842 } while (1); 843 } else { 844 if (max310x_port_irq(s, 0) == IRQ_HANDLED) 845 handled = true; 846 } 847 848 return IRQ_RETVAL(handled); 849 } 850 851 static void max310x_tx_proc(struct work_struct *ws) 852 { 853 struct max310x_one *one = container_of(ws, struct max310x_one, tx_work); 854 855 max310x_handle_tx(&one->port); 856 } 857 858 static unsigned int max310x_tx_empty(struct uart_port *port) 859 { 860 u8 lvl = max310x_port_read(port, MAX310X_TXFIFOLVL_REG); 861 862 return lvl ? 0 : TIOCSER_TEMT; 863 } 864 865 static unsigned int max310x_get_mctrl(struct uart_port *port) 866 { 867 /* DCD and DSR are not wired and CTS/RTS is handled automatically 868 * so just indicate DSR and CAR asserted 869 */ 870 return TIOCM_DSR | TIOCM_CAR; 871 } 872 873 static void max310x_md_proc(struct work_struct *ws) 874 { 875 struct max310x_one *one = container_of(ws, struct max310x_one, md_work); 876 877 max310x_port_update(&one->port, MAX310X_MODE2_REG, 878 MAX310X_MODE2_LOOPBACK_BIT, 879 (one->port.mctrl & TIOCM_LOOP) ? 880 MAX310X_MODE2_LOOPBACK_BIT : 0); 881 } 882 883 static void max310x_set_mctrl(struct uart_port *port, unsigned int mctrl) 884 { 885 struct max310x_one *one = to_max310x_port(port); 886 887 schedule_work(&one->md_work); 888 } 889 890 static void max310x_break_ctl(struct uart_port *port, int break_state) 891 { 892 max310x_port_update(port, MAX310X_LCR_REG, 893 MAX310X_LCR_TXBREAK_BIT, 894 break_state ? MAX310X_LCR_TXBREAK_BIT : 0); 895 } 896 897 static void max310x_set_termios(struct uart_port *port, 898 struct ktermios *termios, 899 struct ktermios *old) 900 { 901 unsigned int lcr = 0, flow = 0; 902 int baud; 903 904 /* Mask termios capabilities we don't support */ 905 termios->c_cflag &= ~CMSPAR; 906 907 /* Word size */ 908 switch (termios->c_cflag & CSIZE) { 909 case CS5: 910 break; 911 case CS6: 912 lcr = MAX310X_LCR_LENGTH0_BIT; 913 break; 914 case CS7: 915 lcr = MAX310X_LCR_LENGTH1_BIT; 916 break; 917 case CS8: 918 default: 919 lcr = MAX310X_LCR_LENGTH1_BIT | MAX310X_LCR_LENGTH0_BIT; 920 break; 921 } 922 923 /* Parity */ 924 if (termios->c_cflag & PARENB) { 925 lcr |= MAX310X_LCR_PARITY_BIT; 926 if (!(termios->c_cflag & PARODD)) 927 lcr |= MAX310X_LCR_EVENPARITY_BIT; 928 } 929 930 /* Stop bits */ 931 if (termios->c_cflag & CSTOPB) 932 lcr |= MAX310X_LCR_STOPLEN_BIT; /* 2 stops */ 933 934 /* Update LCR register */ 935 max310x_port_write(port, MAX310X_LCR_REG, lcr); 936 937 /* Set read status mask */ 938 port->read_status_mask = MAX310X_LSR_RXOVR_BIT; 939 if (termios->c_iflag & INPCK) 940 port->read_status_mask |= MAX310X_LSR_RXPAR_BIT | 941 MAX310X_LSR_FRERR_BIT; 942 if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK)) 943 port->read_status_mask |= MAX310X_LSR_RXBRK_BIT; 944 945 /* Set status ignore mask */ 946 port->ignore_status_mask = 0; 947 if (termios->c_iflag & IGNBRK) 948 port->ignore_status_mask |= MAX310X_LSR_RXBRK_BIT; 949 if (!(termios->c_cflag & CREAD)) 950 port->ignore_status_mask |= MAX310X_LSR_RXPAR_BIT | 951 MAX310X_LSR_RXOVR_BIT | 952 MAX310X_LSR_FRERR_BIT | 953 MAX310X_LSR_RXBRK_BIT; 954 955 /* Configure flow control */ 956 max310x_port_write(port, MAX310X_XON1_REG, termios->c_cc[VSTART]); 957 max310x_port_write(port, MAX310X_XOFF1_REG, termios->c_cc[VSTOP]); 958 959 /* Disable transmitter before enabling AutoCTS or auto transmitter 960 * flow control 961 */ 962 if (termios->c_cflag & CRTSCTS || termios->c_iflag & IXOFF) { 963 max310x_port_update(port, MAX310X_MODE1_REG, 964 MAX310X_MODE1_TXDIS_BIT, 965 MAX310X_MODE1_TXDIS_BIT); 966 } 967 968 port->status &= ~(UPSTAT_AUTOCTS | UPSTAT_AUTORTS | UPSTAT_AUTOXOFF); 969 970 if (termios->c_cflag & CRTSCTS) { 971 /* Enable AUTORTS and AUTOCTS */ 972 port->status |= UPSTAT_AUTOCTS | UPSTAT_AUTORTS; 973 flow |= MAX310X_FLOWCTRL_AUTOCTS_BIT | 974 MAX310X_FLOWCTRL_AUTORTS_BIT; 975 } 976 if (termios->c_iflag & IXON) 977 flow |= MAX310X_FLOWCTRL_SWFLOW3_BIT | 978 MAX310X_FLOWCTRL_SWFLOWEN_BIT; 979 if (termios->c_iflag & IXOFF) { 980 port->status |= UPSTAT_AUTOXOFF; 981 flow |= MAX310X_FLOWCTRL_SWFLOW1_BIT | 982 MAX310X_FLOWCTRL_SWFLOWEN_BIT; 983 } 984 max310x_port_write(port, MAX310X_FLOWCTRL_REG, flow); 985 986 /* Enable transmitter after disabling AutoCTS and auto transmitter 987 * flow control 988 */ 989 if (!(termios->c_cflag & CRTSCTS) && !(termios->c_iflag & IXOFF)) { 990 max310x_port_update(port, MAX310X_MODE1_REG, 991 MAX310X_MODE1_TXDIS_BIT, 992 0); 993 } 994 995 /* Get baud rate generator configuration */ 996 baud = uart_get_baud_rate(port, termios, old, 997 port->uartclk / 16 / 0xffff, 998 port->uartclk / 4); 999 1000 /* Setup baudrate generator */ 1001 baud = max310x_set_baud(port, baud); 1002 1003 /* Update timeout according to new baud rate */ 1004 uart_update_timeout(port, termios->c_cflag, baud); 1005 } 1006 1007 static void max310x_rs_proc(struct work_struct *ws) 1008 { 1009 struct max310x_one *one = container_of(ws, struct max310x_one, rs_work); 1010 unsigned int delay, mode1 = 0, mode2 = 0; 1011 1012 delay = (one->port.rs485.delay_rts_before_send << 4) | 1013 one->port.rs485.delay_rts_after_send; 1014 max310x_port_write(&one->port, MAX310X_HDPIXDELAY_REG, delay); 1015 1016 if (one->port.rs485.flags & SER_RS485_ENABLED) { 1017 mode1 = MAX310X_MODE1_TRNSCVCTRL_BIT; 1018 1019 if (!(one->port.rs485.flags & SER_RS485_RX_DURING_TX)) 1020 mode2 = MAX310X_MODE2_ECHOSUPR_BIT; 1021 } 1022 1023 max310x_port_update(&one->port, MAX310X_MODE1_REG, 1024 MAX310X_MODE1_TRNSCVCTRL_BIT, mode1); 1025 max310x_port_update(&one->port, MAX310X_MODE2_REG, 1026 MAX310X_MODE2_ECHOSUPR_BIT, mode2); 1027 } 1028 1029 static int max310x_rs485_config(struct uart_port *port, 1030 struct serial_rs485 *rs485) 1031 { 1032 struct max310x_one *one = to_max310x_port(port); 1033 1034 if ((rs485->delay_rts_before_send > 0x0f) || 1035 (rs485->delay_rts_after_send > 0x0f)) 1036 return -ERANGE; 1037 1038 rs485->flags &= SER_RS485_RTS_ON_SEND | SER_RS485_RX_DURING_TX | 1039 SER_RS485_ENABLED; 1040 memset(rs485->padding, 0, sizeof(rs485->padding)); 1041 port->rs485 = *rs485; 1042 1043 schedule_work(&one->rs_work); 1044 1045 return 0; 1046 } 1047 1048 static int max310x_startup(struct uart_port *port) 1049 { 1050 struct max310x_port *s = dev_get_drvdata(port->dev); 1051 unsigned int val; 1052 1053 s->devtype->power(port, 1); 1054 1055 /* Configure MODE1 register */ 1056 max310x_port_update(port, MAX310X_MODE1_REG, 1057 MAX310X_MODE1_TRNSCVCTRL_BIT, 0); 1058 1059 /* Configure MODE2 register & Reset FIFOs*/ 1060 val = MAX310X_MODE2_RXEMPTINV_BIT | MAX310X_MODE2_FIFORST_BIT; 1061 max310x_port_write(port, MAX310X_MODE2_REG, val); 1062 max310x_port_update(port, MAX310X_MODE2_REG, 1063 MAX310X_MODE2_FIFORST_BIT, 0); 1064 1065 /* Configure mode1/mode2 to have rs485/rs232 enabled at startup */ 1066 val = (clamp(port->rs485.delay_rts_before_send, 0U, 15U) << 4) | 1067 clamp(port->rs485.delay_rts_after_send, 0U, 15U); 1068 max310x_port_write(port, MAX310X_HDPIXDELAY_REG, val); 1069 1070 if (port->rs485.flags & SER_RS485_ENABLED) { 1071 max310x_port_update(port, MAX310X_MODE1_REG, 1072 MAX310X_MODE1_TRNSCVCTRL_BIT, 1073 MAX310X_MODE1_TRNSCVCTRL_BIT); 1074 1075 if (!(port->rs485.flags & SER_RS485_RX_DURING_TX)) 1076 max310x_port_update(port, MAX310X_MODE2_REG, 1077 MAX310X_MODE2_ECHOSUPR_BIT, 1078 MAX310X_MODE2_ECHOSUPR_BIT); 1079 } 1080 1081 /* Configure flow control levels */ 1082 /* Flow control halt level 96, resume level 48 */ 1083 max310x_port_write(port, MAX310X_FLOWLVL_REG, 1084 MAX310X_FLOWLVL_RES(48) | MAX310X_FLOWLVL_HALT(96)); 1085 1086 /* Clear IRQ status register */ 1087 max310x_port_read(port, MAX310X_IRQSTS_REG); 1088 1089 /* Enable RX, TX, CTS change interrupts */ 1090 val = MAX310X_IRQ_RXEMPTY_BIT | MAX310X_IRQ_TXEMPTY_BIT; 1091 max310x_port_write(port, MAX310X_IRQEN_REG, val | MAX310X_IRQ_CTS_BIT); 1092 1093 return 0; 1094 } 1095 1096 static void max310x_shutdown(struct uart_port *port) 1097 { 1098 struct max310x_port *s = dev_get_drvdata(port->dev); 1099 1100 /* Disable all interrupts */ 1101 max310x_port_write(port, MAX310X_IRQEN_REG, 0); 1102 1103 s->devtype->power(port, 0); 1104 } 1105 1106 static const char *max310x_type(struct uart_port *port) 1107 { 1108 struct max310x_port *s = dev_get_drvdata(port->dev); 1109 1110 return (port->type == PORT_MAX310X) ? s->devtype->name : NULL; 1111 } 1112 1113 static int max310x_request_port(struct uart_port *port) 1114 { 1115 /* Do nothing */ 1116 return 0; 1117 } 1118 1119 static void max310x_config_port(struct uart_port *port, int flags) 1120 { 1121 if (flags & UART_CONFIG_TYPE) 1122 port->type = PORT_MAX310X; 1123 } 1124 1125 static int max310x_verify_port(struct uart_port *port, struct serial_struct *s) 1126 { 1127 if ((s->type != PORT_UNKNOWN) && (s->type != PORT_MAX310X)) 1128 return -EINVAL; 1129 if (s->irq != port->irq) 1130 return -EINVAL; 1131 1132 return 0; 1133 } 1134 1135 static void max310x_null_void(struct uart_port *port) 1136 { 1137 /* Do nothing */ 1138 } 1139 1140 static const struct uart_ops max310x_ops = { 1141 .tx_empty = max310x_tx_empty, 1142 .set_mctrl = max310x_set_mctrl, 1143 .get_mctrl = max310x_get_mctrl, 1144 .stop_tx = max310x_null_void, 1145 .start_tx = max310x_start_tx, 1146 .stop_rx = max310x_null_void, 1147 .break_ctl = max310x_break_ctl, 1148 .startup = max310x_startup, 1149 .shutdown = max310x_shutdown, 1150 .set_termios = max310x_set_termios, 1151 .type = max310x_type, 1152 .request_port = max310x_request_port, 1153 .release_port = max310x_null_void, 1154 .config_port = max310x_config_port, 1155 .verify_port = max310x_verify_port, 1156 }; 1157 1158 static int __maybe_unused max310x_suspend(struct device *dev) 1159 { 1160 struct max310x_port *s = dev_get_drvdata(dev); 1161 int i; 1162 1163 for (i = 0; i < s->devtype->nr; i++) { 1164 uart_suspend_port(&max310x_uart, &s->p[i].port); 1165 s->devtype->power(&s->p[i].port, 0); 1166 } 1167 1168 return 0; 1169 } 1170 1171 static int __maybe_unused max310x_resume(struct device *dev) 1172 { 1173 struct max310x_port *s = dev_get_drvdata(dev); 1174 int i; 1175 1176 for (i = 0; i < s->devtype->nr; i++) { 1177 s->devtype->power(&s->p[i].port, 1); 1178 uart_resume_port(&max310x_uart, &s->p[i].port); 1179 } 1180 1181 return 0; 1182 } 1183 1184 static SIMPLE_DEV_PM_OPS(max310x_pm_ops, max310x_suspend, max310x_resume); 1185 1186 #ifdef CONFIG_GPIOLIB 1187 static int max310x_gpio_get(struct gpio_chip *chip, unsigned offset) 1188 { 1189 unsigned int val; 1190 struct max310x_port *s = gpiochip_get_data(chip); 1191 struct uart_port *port = &s->p[offset / 4].port; 1192 1193 val = max310x_port_read(port, MAX310X_GPIODATA_REG); 1194 1195 return !!((val >> 4) & (1 << (offset % 4))); 1196 } 1197 1198 static void max310x_gpio_set(struct gpio_chip *chip, unsigned offset, int value) 1199 { 1200 struct max310x_port *s = gpiochip_get_data(chip); 1201 struct uart_port *port = &s->p[offset / 4].port; 1202 1203 max310x_port_update(port, MAX310X_GPIODATA_REG, 1 << (offset % 4), 1204 value ? 1 << (offset % 4) : 0); 1205 } 1206 1207 static int max310x_gpio_direction_input(struct gpio_chip *chip, unsigned offset) 1208 { 1209 struct max310x_port *s = gpiochip_get_data(chip); 1210 struct uart_port *port = &s->p[offset / 4].port; 1211 1212 max310x_port_update(port, MAX310X_GPIOCFG_REG, 1 << (offset % 4), 0); 1213 1214 return 0; 1215 } 1216 1217 static int max310x_gpio_direction_output(struct gpio_chip *chip, 1218 unsigned offset, int value) 1219 { 1220 struct max310x_port *s = gpiochip_get_data(chip); 1221 struct uart_port *port = &s->p[offset / 4].port; 1222 1223 max310x_port_update(port, MAX310X_GPIODATA_REG, 1 << (offset % 4), 1224 value ? 1 << (offset % 4) : 0); 1225 max310x_port_update(port, MAX310X_GPIOCFG_REG, 1 << (offset % 4), 1226 1 << (offset % 4)); 1227 1228 return 0; 1229 } 1230 1231 static int max310x_gpio_set_config(struct gpio_chip *chip, unsigned int offset, 1232 unsigned long config) 1233 { 1234 struct max310x_port *s = gpiochip_get_data(chip); 1235 struct uart_port *port = &s->p[offset / 4].port; 1236 1237 switch (pinconf_to_config_param(config)) { 1238 case PIN_CONFIG_DRIVE_OPEN_DRAIN: 1239 max310x_port_update(port, MAX310X_GPIOCFG_REG, 1240 1 << ((offset % 4) + 4), 1241 1 << ((offset % 4) + 4)); 1242 return 0; 1243 case PIN_CONFIG_DRIVE_PUSH_PULL: 1244 max310x_port_update(port, MAX310X_GPIOCFG_REG, 1245 1 << ((offset % 4) + 4), 0); 1246 return 0; 1247 default: 1248 return -ENOTSUPP; 1249 } 1250 } 1251 #endif 1252 1253 static int max310x_probe(struct device *dev, struct max310x_devtype *devtype, 1254 struct regmap *regmap, int irq) 1255 { 1256 int i, ret, fmin, fmax, freq, uartclk; 1257 struct clk *clk_osc, *clk_xtal; 1258 struct max310x_port *s; 1259 bool xtal = false; 1260 1261 if (IS_ERR(regmap)) 1262 return PTR_ERR(regmap); 1263 1264 /* Alloc port structure */ 1265 s = devm_kzalloc(dev, struct_size(s, p, devtype->nr), GFP_KERNEL); 1266 if (!s) { 1267 dev_err(dev, "Error allocating port structure\n"); 1268 return -ENOMEM; 1269 } 1270 1271 clk_osc = devm_clk_get(dev, "osc"); 1272 clk_xtal = devm_clk_get(dev, "xtal"); 1273 if (!IS_ERR(clk_osc)) { 1274 s->clk = clk_osc; 1275 fmin = 500000; 1276 fmax = 35000000; 1277 } else if (!IS_ERR(clk_xtal)) { 1278 s->clk = clk_xtal; 1279 fmin = 1000000; 1280 fmax = 4000000; 1281 xtal = true; 1282 } else if (PTR_ERR(clk_osc) == -EPROBE_DEFER || 1283 PTR_ERR(clk_xtal) == -EPROBE_DEFER) { 1284 return -EPROBE_DEFER; 1285 } else { 1286 dev_err(dev, "Cannot get clock\n"); 1287 return -EINVAL; 1288 } 1289 1290 ret = clk_prepare_enable(s->clk); 1291 if (ret) 1292 return ret; 1293 1294 freq = clk_get_rate(s->clk); 1295 /* Check frequency limits */ 1296 if (freq < fmin || freq > fmax) { 1297 ret = -ERANGE; 1298 goto out_clk; 1299 } 1300 1301 s->regmap = regmap; 1302 s->devtype = devtype; 1303 dev_set_drvdata(dev, s); 1304 1305 /* Check device to ensure we are talking to what we expect */ 1306 ret = devtype->detect(dev); 1307 if (ret) 1308 goto out_clk; 1309 1310 for (i = 0; i < devtype->nr; i++) { 1311 unsigned int offs = i << 5; 1312 1313 /* Reset port */ 1314 regmap_write(s->regmap, MAX310X_MODE2_REG + offs, 1315 MAX310X_MODE2_RST_BIT); 1316 /* Clear port reset */ 1317 regmap_write(s->regmap, MAX310X_MODE2_REG + offs, 0); 1318 1319 /* Wait for port startup */ 1320 do { 1321 regmap_read(s->regmap, 1322 MAX310X_BRGDIVLSB_REG + offs, &ret); 1323 } while (ret != 0x01); 1324 1325 regmap_write(s->regmap, MAX310X_MODE1_REG + offs, 1326 devtype->mode1); 1327 } 1328 1329 uartclk = max310x_set_ref_clk(dev, s, freq, xtal); 1330 dev_dbg(dev, "Reference clock set to %i Hz\n", uartclk); 1331 1332 for (i = 0; i < devtype->nr; i++) { 1333 unsigned int line; 1334 1335 line = find_first_zero_bit(max310x_lines, MAX310X_UART_NRMAX); 1336 if (line == MAX310X_UART_NRMAX) { 1337 ret = -ERANGE; 1338 goto out_uart; 1339 } 1340 1341 /* Initialize port data */ 1342 s->p[i].port.line = line; 1343 s->p[i].port.dev = dev; 1344 s->p[i].port.irq = irq; 1345 s->p[i].port.type = PORT_MAX310X; 1346 s->p[i].port.fifosize = MAX310X_FIFO_SIZE; 1347 s->p[i].port.flags = UPF_FIXED_TYPE | UPF_LOW_LATENCY; 1348 s->p[i].port.iotype = UPIO_PORT; 1349 s->p[i].port.iobase = i * 0x20; 1350 s->p[i].port.membase = (void __iomem *)~0; 1351 s->p[i].port.uartclk = uartclk; 1352 s->p[i].port.rs485_config = max310x_rs485_config; 1353 s->p[i].port.ops = &max310x_ops; 1354 /* Disable all interrupts */ 1355 max310x_port_write(&s->p[i].port, MAX310X_IRQEN_REG, 0); 1356 /* Clear IRQ status register */ 1357 max310x_port_read(&s->p[i].port, MAX310X_IRQSTS_REG); 1358 /* Initialize queue for start TX */ 1359 INIT_WORK(&s->p[i].tx_work, max310x_tx_proc); 1360 /* Initialize queue for changing LOOPBACK mode */ 1361 INIT_WORK(&s->p[i].md_work, max310x_md_proc); 1362 /* Initialize queue for changing RS485 mode */ 1363 INIT_WORK(&s->p[i].rs_work, max310x_rs_proc); 1364 /* Initialize SPI-transfer buffers */ 1365 s->p[i].wr_header = (s->p[i].port.iobase + MAX310X_THR_REG) | 1366 MAX310X_WRITE_BIT; 1367 s->p[i].rd_header = (s->p[i].port.iobase + MAX310X_RHR_REG); 1368 1369 /* Register port */ 1370 ret = uart_add_one_port(&max310x_uart, &s->p[i].port); 1371 if (ret) { 1372 s->p[i].port.dev = NULL; 1373 goto out_uart; 1374 } 1375 set_bit(line, max310x_lines); 1376 1377 /* Go to suspend mode */ 1378 devtype->power(&s->p[i].port, 0); 1379 } 1380 1381 #ifdef CONFIG_GPIOLIB 1382 /* Setup GPIO cotroller */ 1383 s->gpio.owner = THIS_MODULE; 1384 s->gpio.parent = dev; 1385 s->gpio.label = devtype->name; 1386 s->gpio.direction_input = max310x_gpio_direction_input; 1387 s->gpio.get = max310x_gpio_get; 1388 s->gpio.direction_output= max310x_gpio_direction_output; 1389 s->gpio.set = max310x_gpio_set; 1390 s->gpio.set_config = max310x_gpio_set_config; 1391 s->gpio.base = -1; 1392 s->gpio.ngpio = devtype->nr * 4; 1393 s->gpio.can_sleep = 1; 1394 ret = devm_gpiochip_add_data(dev, &s->gpio, s); 1395 if (ret) 1396 goto out_uart; 1397 #endif 1398 1399 /* Setup interrupt */ 1400 ret = devm_request_threaded_irq(dev, irq, NULL, max310x_ist, 1401 IRQF_ONESHOT | IRQF_SHARED, dev_name(dev), s); 1402 if (!ret) 1403 return 0; 1404 1405 dev_err(dev, "Unable to reguest IRQ %i\n", irq); 1406 1407 out_uart: 1408 for (i = 0; i < devtype->nr; i++) { 1409 if (s->p[i].port.dev) { 1410 uart_remove_one_port(&max310x_uart, &s->p[i].port); 1411 clear_bit(s->p[i].port.line, max310x_lines); 1412 } 1413 } 1414 1415 out_clk: 1416 clk_disable_unprepare(s->clk); 1417 1418 return ret; 1419 } 1420 1421 static int max310x_remove(struct device *dev) 1422 { 1423 struct max310x_port *s = dev_get_drvdata(dev); 1424 int i; 1425 1426 for (i = 0; i < s->devtype->nr; i++) { 1427 cancel_work_sync(&s->p[i].tx_work); 1428 cancel_work_sync(&s->p[i].md_work); 1429 cancel_work_sync(&s->p[i].rs_work); 1430 uart_remove_one_port(&max310x_uart, &s->p[i].port); 1431 clear_bit(s->p[i].port.line, max310x_lines); 1432 s->devtype->power(&s->p[i].port, 0); 1433 } 1434 1435 clk_disable_unprepare(s->clk); 1436 1437 return 0; 1438 } 1439 1440 static const struct of_device_id __maybe_unused max310x_dt_ids[] = { 1441 { .compatible = "maxim,max3107", .data = &max3107_devtype, }, 1442 { .compatible = "maxim,max3108", .data = &max3108_devtype, }, 1443 { .compatible = "maxim,max3109", .data = &max3109_devtype, }, 1444 { .compatible = "maxim,max14830", .data = &max14830_devtype }, 1445 { } 1446 }; 1447 MODULE_DEVICE_TABLE(of, max310x_dt_ids); 1448 1449 static struct regmap_config regcfg = { 1450 .reg_bits = 8, 1451 .val_bits = 8, 1452 .write_flag_mask = MAX310X_WRITE_BIT, 1453 .cache_type = REGCACHE_RBTREE, 1454 .writeable_reg = max310x_reg_writeable, 1455 .volatile_reg = max310x_reg_volatile, 1456 .precious_reg = max310x_reg_precious, 1457 }; 1458 1459 #ifdef CONFIG_SPI_MASTER 1460 static int max310x_spi_probe(struct spi_device *spi) 1461 { 1462 struct max310x_devtype *devtype; 1463 struct regmap *regmap; 1464 int ret; 1465 1466 /* Setup SPI bus */ 1467 spi->bits_per_word = 8; 1468 spi->mode = spi->mode ? : SPI_MODE_0; 1469 spi->max_speed_hz = spi->max_speed_hz ? : 26000000; 1470 ret = spi_setup(spi); 1471 if (ret) 1472 return ret; 1473 1474 if (spi->dev.of_node) { 1475 const struct of_device_id *of_id = 1476 of_match_device(max310x_dt_ids, &spi->dev); 1477 if (!of_id) 1478 return -ENODEV; 1479 1480 devtype = (struct max310x_devtype *)of_id->data; 1481 } else { 1482 const struct spi_device_id *id_entry = spi_get_device_id(spi); 1483 1484 devtype = (struct max310x_devtype *)id_entry->driver_data; 1485 } 1486 1487 regcfg.max_register = devtype->nr * 0x20 - 1; 1488 regmap = devm_regmap_init_spi(spi, ®cfg); 1489 1490 return max310x_probe(&spi->dev, devtype, regmap, spi->irq); 1491 } 1492 1493 static int max310x_spi_remove(struct spi_device *spi) 1494 { 1495 return max310x_remove(&spi->dev); 1496 } 1497 1498 static const struct spi_device_id max310x_id_table[] = { 1499 { "max3107", (kernel_ulong_t)&max3107_devtype, }, 1500 { "max3108", (kernel_ulong_t)&max3108_devtype, }, 1501 { "max3109", (kernel_ulong_t)&max3109_devtype, }, 1502 { "max14830", (kernel_ulong_t)&max14830_devtype, }, 1503 { } 1504 }; 1505 MODULE_DEVICE_TABLE(spi, max310x_id_table); 1506 1507 static struct spi_driver max310x_spi_driver = { 1508 .driver = { 1509 .name = MAX310X_NAME, 1510 .of_match_table = of_match_ptr(max310x_dt_ids), 1511 .pm = &max310x_pm_ops, 1512 }, 1513 .probe = max310x_spi_probe, 1514 .remove = max310x_spi_remove, 1515 .id_table = max310x_id_table, 1516 }; 1517 #endif 1518 1519 static int __init max310x_uart_init(void) 1520 { 1521 int ret; 1522 1523 bitmap_zero(max310x_lines, MAX310X_UART_NRMAX); 1524 1525 ret = uart_register_driver(&max310x_uart); 1526 if (ret) 1527 return ret; 1528 1529 #ifdef CONFIG_SPI_MASTER 1530 ret = spi_register_driver(&max310x_spi_driver); 1531 #endif 1532 1533 return ret; 1534 } 1535 module_init(max310x_uart_init); 1536 1537 static void __exit max310x_uart_exit(void) 1538 { 1539 #ifdef CONFIG_SPI_MASTER 1540 spi_unregister_driver(&max310x_spi_driver); 1541 #endif 1542 1543 uart_unregister_driver(&max310x_uart); 1544 } 1545 module_exit(max310x_uart_exit); 1546 1547 MODULE_LICENSE("GPL"); 1548 MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>"); 1549 MODULE_DESCRIPTION("MAX310X serial driver"); 1550