1// SPDX-License-Identifier: GPL-2.0-only 2/* 3 * Copyright (C) 2011 LAPIS Semiconductor Co., Ltd. 4 */ 5 6#include <linux/module.h> 7#include <linux/kernel.h> 8#include <linux/delay.h> 9#include <linux/errno.h> 10#include <linux/i2c.h> 11#include <linux/fs.h> 12#include <linux/io.h> 13#include <linux/types.h> 14#include <linux/interrupt.h> 15#include <linux/jiffies.h> 16#include <linux/pci.h> 17#include <linux/mutex.h> 18#include <linux/ktime.h> 19#include <linux/slab.h> 20 21#define PCH_EVENT_SET 0 /* I2C Interrupt Event Set Status */ 22#define PCH_EVENT_NONE 1 /* I2C Interrupt Event Clear Status */ 23#define PCH_MAX_CLK 100000 /* Maximum Clock speed in MHz */ 24#define PCH_BUFFER_MODE_ENABLE 0x0002 /* flag for Buffer mode enable */ 25#define PCH_EEPROM_SW_RST_MODE_ENABLE 0x0008 /* EEPROM SW RST enable flag */ 26 27#define PCH_I2CSADR 0x00 /* I2C slave address register */ 28#define PCH_I2CCTL 0x04 /* I2C control register */ 29#define PCH_I2CSR 0x08 /* I2C status register */ 30#define PCH_I2CDR 0x0C /* I2C data register */ 31#define PCH_I2CMON 0x10 /* I2C bus monitor register */ 32#define PCH_I2CBC 0x14 /* I2C bus transfer rate setup counter */ 33#define PCH_I2CMOD 0x18 /* I2C mode register */ 34#define PCH_I2CBUFSLV 0x1C /* I2C buffer mode slave address register */ 35#define PCH_I2CBUFSUB 0x20 /* I2C buffer mode subaddress register */ 36#define PCH_I2CBUFFOR 0x24 /* I2C buffer mode format register */ 37#define PCH_I2CBUFCTL 0x28 /* I2C buffer mode control register */ 38#define PCH_I2CBUFMSK 0x2C /* I2C buffer mode interrupt mask register */ 39#define PCH_I2CBUFSTA 0x30 /* I2C buffer mode status register */ 40#define PCH_I2CBUFLEV 0x34 /* I2C buffer mode level register */ 41#define PCH_I2CESRFOR 0x38 /* EEPROM software reset mode format register */ 42#define PCH_I2CESRCTL 0x3C /* EEPROM software reset mode ctrl register */ 43#define PCH_I2CESRMSK 0x40 /* EEPROM software reset mode */ 44#define PCH_I2CESRSTA 0x44 /* EEPROM software reset mode status register */ 45#define PCH_I2CTMR 0x48 /* I2C timer register */ 46#define PCH_I2CSRST 0xFC /* I2C reset register */ 47#define PCH_I2CNF 0xF8 /* I2C noise filter register */ 48 49#define BUS_IDLE_TIMEOUT 20 50#define PCH_I2CCTL_I2CMEN 0x0080 51#define TEN_BIT_ADDR_DEFAULT 0xF000 52#define TEN_BIT_ADDR_MASK 0xF0 53#define PCH_START 0x0020 54#define PCH_RESTART 0x0004 55#define PCH_ESR_START 0x0001 56#define PCH_BUFF_START 0x1 57#define PCH_REPSTART 0x0004 58#define PCH_ACK 0x0008 59#define PCH_GETACK 0x0001 60#define CLR_REG 0x0 61#define I2C_RD 0x1 62#define I2CMCF_BIT 0x0080 63#define I2CMIF_BIT 0x0002 64#define I2CMAL_BIT 0x0010 65#define I2CBMFI_BIT 0x0001 66#define I2CBMAL_BIT 0x0002 67#define I2CBMNA_BIT 0x0004 68#define I2CBMTO_BIT 0x0008 69#define I2CBMIS_BIT 0x0010 70#define I2CESRFI_BIT 0X0001 71#define I2CESRTO_BIT 0x0002 72#define I2CESRFIIE_BIT 0x1 73#define I2CESRTOIE_BIT 0x2 74#define I2CBMDZ_BIT 0x0040 75#define I2CBMAG_BIT 0x0020 76#define I2CMBB_BIT 0x0020 77#define BUFFER_MODE_MASK (I2CBMFI_BIT | I2CBMAL_BIT | I2CBMNA_BIT | \ 78 I2CBMTO_BIT | I2CBMIS_BIT) 79#define I2C_ADDR_MSK 0xFF 80#define I2C_MSB_2B_MSK 0x300 81#define FAST_MODE_CLK 400 82#define FAST_MODE_EN 0x0001 83#define SUB_ADDR_LEN_MAX 4 84#define BUF_LEN_MAX 32 85#define PCH_BUFFER_MODE 0x1 86#define EEPROM_SW_RST_MODE 0x0002 87#define NORMAL_INTR_ENBL 0x0300 88#define EEPROM_RST_INTR_ENBL (I2CESRFIIE_BIT | I2CESRTOIE_BIT) 89#define EEPROM_RST_INTR_DISBL 0x0 90#define BUFFER_MODE_INTR_ENBL 0x001F 91#define BUFFER_MODE_INTR_DISBL 0x0 92#define NORMAL_MODE 0x0 93#define BUFFER_MODE 0x1 94#define EEPROM_SR_MODE 0x2 95#define I2C_TX_MODE 0x0010 96#define PCH_BUF_TX 0xFFF7 97#define PCH_BUF_RD 0x0008 98#define I2C_ERROR_MASK (I2CESRTO_EVENT | I2CBMIS_EVENT | I2CBMTO_EVENT | \ 99 I2CBMNA_EVENT | I2CBMAL_EVENT | I2CMAL_EVENT) 100#define I2CMAL_EVENT 0x0001 101#define I2CMCF_EVENT 0x0002 102#define I2CBMFI_EVENT 0x0004 103#define I2CBMAL_EVENT 0x0008 104#define I2CBMNA_EVENT 0x0010 105#define I2CBMTO_EVENT 0x0020 106#define I2CBMIS_EVENT 0x0040 107#define I2CESRFI_EVENT 0x0080 108#define I2CESRTO_EVENT 0x0100 109#define PCI_DEVICE_ID_PCH_I2C 0x8817 110 111#define pch_dbg(adap, fmt, arg...) \ 112 dev_dbg(adap->pch_adapter.dev.parent, "%s :" fmt, __func__, ##arg) 113 114#define pch_err(adap, fmt, arg...) \ 115 dev_err(adap->pch_adapter.dev.parent, "%s :" fmt, __func__, ##arg) 116 117#define pch_pci_err(pdev, fmt, arg...) \ 118 dev_err(&pdev->dev, "%s :" fmt, __func__, ##arg) 119 120#define pch_pci_dbg(pdev, fmt, arg...) \ 121 dev_dbg(&pdev->dev, "%s :" fmt, __func__, ##arg) 122 123/* 124Set the number of I2C instance max 125Intel EG20T PCH : 1ch 126LAPIS Semiconductor ML7213 IOH : 2ch 127LAPIS Semiconductor ML7831 IOH : 1ch 128*/ 129#define PCH_I2C_MAX_DEV 2 130 131/** 132 * struct i2c_algo_pch_data - for I2C driver functionalities 133 * @pch_adapter: stores the reference to i2c_adapter structure 134 * @p_adapter_info: stores the reference to adapter_info structure 135 * @pch_base_address: specifies the remapped base address 136 * @pch_buff_mode_en: specifies if buffer mode is enabled 137 * @pch_event_flag: specifies occurrence of interrupt events 138 * @pch_i2c_xfer_in_progress: specifies whether the transfer is completed 139 */ 140struct i2c_algo_pch_data { 141 struct i2c_adapter pch_adapter; 142 struct adapter_info *p_adapter_info; 143 void __iomem *pch_base_address; 144 int pch_buff_mode_en; 145 u32 pch_event_flag; 146 bool pch_i2c_xfer_in_progress; 147}; 148 149/** 150 * struct adapter_info - This structure holds the adapter information for the 151 * PCH i2c controller 152 * @pch_data: stores a list of i2c_algo_pch_data 153 * @pch_i2c_suspended: specifies whether the system is suspended or not 154 * perhaps with more lines and words. 155 * @ch_num: specifies the number of i2c instance 156 * 157 * pch_data has as many elements as maximum I2C channels 158 */ 159struct adapter_info { 160 struct i2c_algo_pch_data pch_data[PCH_I2C_MAX_DEV]; 161 bool pch_i2c_suspended; 162 int ch_num; 163}; 164 165 166static int pch_i2c_speed = 100; /* I2C bus speed in Kbps */ 167static int pch_clk = 50000; /* specifies I2C clock speed in KHz */ 168static wait_queue_head_t pch_event; 169static DEFINE_MUTEX(pch_mutex); 170 171/* Definition for ML7213 by LAPIS Semiconductor */ 172#define PCI_DEVICE_ID_ML7213_I2C 0x802D 173#define PCI_DEVICE_ID_ML7223_I2C 0x8010 174#define PCI_DEVICE_ID_ML7831_I2C 0x8817 175 176static const struct pci_device_id pch_pcidev_id[] = { 177 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_PCH_I2C), 1, }, 178 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_I2C), 2, }, 179 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_I2C), 1, }, 180 { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7831_I2C), 1, }, 181 {0,} 182}; 183MODULE_DEVICE_TABLE(pci, pch_pcidev_id); 184 185static irqreturn_t pch_i2c_handler(int irq, void *pData); 186 187static inline void pch_setbit(void __iomem *addr, u32 offset, u32 bitmask) 188{ 189 u32 val; 190 val = ioread32(addr + offset); 191 val |= bitmask; 192 iowrite32(val, addr + offset); 193} 194 195static inline void pch_clrbit(void __iomem *addr, u32 offset, u32 bitmask) 196{ 197 u32 val; 198 val = ioread32(addr + offset); 199 val &= (~bitmask); 200 iowrite32(val, addr + offset); 201} 202 203/** 204 * pch_i2c_init() - hardware initialization of I2C module 205 * @adap: Pointer to struct i2c_algo_pch_data. 206 */ 207static void pch_i2c_init(struct i2c_algo_pch_data *adap) 208{ 209 void __iomem *p = adap->pch_base_address; 210 u32 pch_i2cbc; 211 u32 pch_i2ctmr; 212 u32 reg_value; 213 214 /* reset I2C controller */ 215 iowrite32(0x01, p + PCH_I2CSRST); 216 msleep(20); 217 iowrite32(0x0, p + PCH_I2CSRST); 218 219 /* Initialize I2C registers */ 220 iowrite32(0x21, p + PCH_I2CNF); 221 222 pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_I2CCTL_I2CMEN); 223 224 if (pch_i2c_speed != 400) 225 pch_i2c_speed = 100; 226 227 reg_value = PCH_I2CCTL_I2CMEN; 228 if (pch_i2c_speed == FAST_MODE_CLK) { 229 reg_value |= FAST_MODE_EN; 230 pch_dbg(adap, "Fast mode enabled\n"); 231 } 232 233 if (pch_clk > PCH_MAX_CLK) 234 pch_clk = 62500; 235 236 pch_i2cbc = (pch_clk + (pch_i2c_speed * 4)) / (pch_i2c_speed * 8); 237 /* Set transfer speed in I2CBC */ 238 iowrite32(pch_i2cbc, p + PCH_I2CBC); 239 240 pch_i2ctmr = (pch_clk) / 8; 241 iowrite32(pch_i2ctmr, p + PCH_I2CTMR); 242 243 reg_value |= NORMAL_INTR_ENBL; /* Enable interrupts in normal mode */ 244 iowrite32(reg_value, p + PCH_I2CCTL); 245 246 pch_dbg(adap, 247 "I2CCTL=%x pch_i2cbc=%x pch_i2ctmr=%x Enable interrupts\n", 248 ioread32(p + PCH_I2CCTL), pch_i2cbc, pch_i2ctmr); 249 250 init_waitqueue_head(&pch_event); 251} 252 253/** 254 * pch_i2c_wait_for_bus_idle() - check the status of bus. 255 * @adap: Pointer to struct i2c_algo_pch_data. 256 * @timeout: waiting time counter (ms). 257 */ 258static s32 pch_i2c_wait_for_bus_idle(struct i2c_algo_pch_data *adap, 259 s32 timeout) 260{ 261 void __iomem *p = adap->pch_base_address; 262 int schedule = 0; 263 unsigned long end = jiffies + msecs_to_jiffies(timeout); 264 265 while (ioread32(p + PCH_I2CSR) & I2CMBB_BIT) { 266 if (time_after(jiffies, end)) { 267 pch_dbg(adap, "I2CSR = %x\n", ioread32(p + PCH_I2CSR)); 268 pch_err(adap, "%s: Timeout Error.return%d\n", 269 __func__, -ETIME); 270 pch_i2c_init(adap); 271 272 return -ETIME; 273 } 274 275 if (!schedule) 276 /* Retry after some usecs */ 277 udelay(5); 278 else 279 /* Wait a bit more without consuming CPU */ 280 usleep_range(20, 1000); 281 282 schedule = 1; 283 } 284 285 return 0; 286} 287 288/** 289 * pch_i2c_start() - Generate I2C start condition in normal mode. 290 * @adap: Pointer to struct i2c_algo_pch_data. 291 * 292 * Generate I2C start condition in normal mode by setting I2CCTL.I2CMSTA to 1. 293 */ 294static void pch_i2c_start(struct i2c_algo_pch_data *adap) 295{ 296 void __iomem *p = adap->pch_base_address; 297 pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL)); 298 pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_START); 299} 300 301/** 302 * pch_i2c_stop() - generate stop condition in normal mode. 303 * @adap: Pointer to struct i2c_algo_pch_data. 304 */ 305static void pch_i2c_stop(struct i2c_algo_pch_data *adap) 306{ 307 void __iomem *p = adap->pch_base_address; 308 pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL)); 309 /* clear the start bit */ 310 pch_clrbit(adap->pch_base_address, PCH_I2CCTL, PCH_START); 311} 312 313static int pch_i2c_wait_for_check_xfer(struct i2c_algo_pch_data *adap) 314{ 315 long ret; 316 void __iomem *p = adap->pch_base_address; 317 318 ret = wait_event_timeout(pch_event, 319 (adap->pch_event_flag != 0), msecs_to_jiffies(1000)); 320 if (!ret) { 321 pch_err(adap, "%s:wait-event timeout\n", __func__); 322 adap->pch_event_flag = 0; 323 pch_i2c_stop(adap); 324 pch_i2c_init(adap); 325 return -ETIMEDOUT; 326 } 327 328 if (adap->pch_event_flag & I2C_ERROR_MASK) { 329 pch_err(adap, "Lost Arbitration\n"); 330 adap->pch_event_flag = 0; 331 pch_clrbit(adap->pch_base_address, PCH_I2CSR, I2CMAL_BIT); 332 pch_clrbit(adap->pch_base_address, PCH_I2CSR, I2CMIF_BIT); 333 pch_i2c_init(adap); 334 return -EAGAIN; 335 } 336 337 adap->pch_event_flag = 0; 338 339 if (ioread32(p + PCH_I2CSR) & PCH_GETACK) { 340 pch_dbg(adap, "Receive NACK for slave address setting\n"); 341 return -ENXIO; 342 } 343 344 return 0; 345} 346 347/** 348 * pch_i2c_repstart() - generate repeated start condition in normal mode 349 * @adap: Pointer to struct i2c_algo_pch_data. 350 */ 351static void pch_i2c_repstart(struct i2c_algo_pch_data *adap) 352{ 353 void __iomem *p = adap->pch_base_address; 354 pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL)); 355 pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_REPSTART); 356} 357 358/** 359 * pch_i2c_writebytes() - write data to I2C bus in normal mode 360 * @i2c_adap: Pointer to the struct i2c_adapter. 361 * @msgs: Pointer to the i2c message structure. 362 * @last: specifies whether last message or not. 363 * In the case of compound mode it will be 1 for last message, 364 * otherwise 0. 365 * @first: specifies whether first message or not. 366 * 1 for first message otherwise 0. 367 */ 368static s32 pch_i2c_writebytes(struct i2c_adapter *i2c_adap, 369 struct i2c_msg *msgs, u32 last, u32 first) 370{ 371 struct i2c_algo_pch_data *adap = i2c_adap->algo_data; 372 u8 *buf; 373 u32 length; 374 u32 addr; 375 u32 addr_2_msb; 376 u32 addr_8_lsb; 377 s32 wrcount; 378 s32 rtn; 379 void __iomem *p = adap->pch_base_address; 380 381 length = msgs->len; 382 buf = msgs->buf; 383 addr = msgs->addr; 384 385 /* enable master tx */ 386 pch_setbit(adap->pch_base_address, PCH_I2CCTL, I2C_TX_MODE); 387 388 pch_dbg(adap, "I2CCTL = %x msgs->len = %d\n", ioread32(p + PCH_I2CCTL), 389 length); 390 391 if (first) { 392 if (pch_i2c_wait_for_bus_idle(adap, BUS_IDLE_TIMEOUT) == -ETIME) 393 return -ETIME; 394 } 395 396 if (msgs->flags & I2C_M_TEN) { 397 addr_2_msb = ((addr & I2C_MSB_2B_MSK) >> 7) & 0x06; 398 iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, p + PCH_I2CDR); 399 if (first) 400 pch_i2c_start(adap); 401 402 rtn = pch_i2c_wait_for_check_xfer(adap); 403 if (rtn) 404 return rtn; 405 406 addr_8_lsb = (addr & I2C_ADDR_MSK); 407 iowrite32(addr_8_lsb, p + PCH_I2CDR); 408 } else { 409 /* set 7 bit slave address and R/W bit as 0 */ 410 iowrite32(i2c_8bit_addr_from_msg(msgs), p + PCH_I2CDR); 411 if (first) 412 pch_i2c_start(adap); 413 } 414 415 rtn = pch_i2c_wait_for_check_xfer(adap); 416 if (rtn) 417 return rtn; 418 419 for (wrcount = 0; wrcount < length; ++wrcount) { 420 /* write buffer value to I2C data register */ 421 iowrite32(buf[wrcount], p + PCH_I2CDR); 422 pch_dbg(adap, "writing %x to Data register\n", buf[wrcount]); 423 424 rtn = pch_i2c_wait_for_check_xfer(adap); 425 if (rtn) 426 return rtn; 427 428 pch_clrbit(adap->pch_base_address, PCH_I2CSR, I2CMCF_BIT); 429 pch_clrbit(adap->pch_base_address, PCH_I2CSR, I2CMIF_BIT); 430 } 431 432 /* check if this is the last message */ 433 if (last) 434 pch_i2c_stop(adap); 435 else 436 pch_i2c_repstart(adap); 437 438 pch_dbg(adap, "return=%d\n", wrcount); 439 440 return wrcount; 441} 442 443/** 444 * pch_i2c_sendack() - send ACK 445 * @adap: Pointer to struct i2c_algo_pch_data. 446 */ 447static void pch_i2c_sendack(struct i2c_algo_pch_data *adap) 448{ 449 void __iomem *p = adap->pch_base_address; 450 pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL)); 451 pch_clrbit(adap->pch_base_address, PCH_I2CCTL, PCH_ACK); 452} 453 454/** 455 * pch_i2c_sendnack() - send NACK 456 * @adap: Pointer to struct i2c_algo_pch_data. 457 */ 458static void pch_i2c_sendnack(struct i2c_algo_pch_data *adap) 459{ 460 void __iomem *p = adap->pch_base_address; 461 pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL)); 462 pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_ACK); 463} 464 465/** 466 * pch_i2c_restart() - Generate I2C restart condition in normal mode. 467 * @adap: Pointer to struct i2c_algo_pch_data. 468 * 469 * Generate I2C restart condition in normal mode by setting I2CCTL.I2CRSTA. 470 */ 471static void pch_i2c_restart(struct i2c_algo_pch_data *adap) 472{ 473 void __iomem *p = adap->pch_base_address; 474 pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL)); 475 pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_RESTART); 476} 477 478/** 479 * pch_i2c_readbytes() - read data from I2C bus in normal mode. 480 * @i2c_adap: Pointer to the struct i2c_adapter. 481 * @msgs: Pointer to i2c_msg structure. 482 * @last: specifies whether last message or not. 483 * @first: specifies whether first message or not. 484 */ 485static s32 pch_i2c_readbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, 486 u32 last, u32 first) 487{ 488 struct i2c_algo_pch_data *adap = i2c_adap->algo_data; 489 490 u8 *buf; 491 u32 count; 492 u32 length; 493 u32 addr; 494 u32 addr_2_msb; 495 u32 addr_8_lsb; 496 void __iomem *p = adap->pch_base_address; 497 s32 rtn; 498 499 length = msgs->len; 500 buf = msgs->buf; 501 addr = msgs->addr; 502 503 /* enable master reception */ 504 pch_clrbit(adap->pch_base_address, PCH_I2CCTL, I2C_TX_MODE); 505 506 if (first) { 507 if (pch_i2c_wait_for_bus_idle(adap, BUS_IDLE_TIMEOUT) == -ETIME) 508 return -ETIME; 509 } 510 511 if (msgs->flags & I2C_M_TEN) { 512 addr_2_msb = ((addr & I2C_MSB_2B_MSK) >> 7); 513 iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, p + PCH_I2CDR); 514 if (first) 515 pch_i2c_start(adap); 516 517 rtn = pch_i2c_wait_for_check_xfer(adap); 518 if (rtn) 519 return rtn; 520 521 addr_8_lsb = (addr & I2C_ADDR_MSK); 522 iowrite32(addr_8_lsb, p + PCH_I2CDR); 523 524 pch_i2c_restart(adap); 525 526 rtn = pch_i2c_wait_for_check_xfer(adap); 527 if (rtn) 528 return rtn; 529 530 addr_2_msb |= I2C_RD; 531 iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, p + PCH_I2CDR); 532 } else { 533 /* 7 address bits + R/W bit */ 534 iowrite32(i2c_8bit_addr_from_msg(msgs), p + PCH_I2CDR); 535 } 536 537 /* check if it is the first message */ 538 if (first) 539 pch_i2c_start(adap); 540 541 rtn = pch_i2c_wait_for_check_xfer(adap); 542 if (rtn) 543 return rtn; 544 545 if (length == 0) { 546 pch_i2c_stop(adap); 547 ioread32(p + PCH_I2CDR); /* Dummy read needs */ 548 549 count = length; 550 } else { 551 int read_index; 552 int loop; 553 pch_i2c_sendack(adap); 554 555 /* Dummy read */ 556 for (loop = 1, read_index = 0; loop < length; loop++) { 557 buf[read_index] = ioread32(p + PCH_I2CDR); 558 559 if (loop != 1) 560 read_index++; 561 562 rtn = pch_i2c_wait_for_check_xfer(adap); 563 if (rtn) 564 return rtn; 565 } /* end for */ 566 567 pch_i2c_sendnack(adap); 568 569 buf[read_index] = ioread32(p + PCH_I2CDR); /* Read final - 1 */ 570 571 if (length != 1) 572 read_index++; 573 574 rtn = pch_i2c_wait_for_check_xfer(adap); 575 if (rtn) 576 return rtn; 577 578 if (last) 579 pch_i2c_stop(adap); 580 else 581 pch_i2c_repstart(adap); 582 583 buf[read_index++] = ioread32(p + PCH_I2CDR); /* Read Final */ 584 count = read_index; 585 } 586 587 return count; 588} 589 590/** 591 * pch_i2c_cb() - Interrupt handler Call back function 592 * @adap: Pointer to struct i2c_algo_pch_data. 593 */ 594static void pch_i2c_cb(struct i2c_algo_pch_data *adap) 595{ 596 u32 sts; 597 void __iomem *p = adap->pch_base_address; 598 599 sts = ioread32(p + PCH_I2CSR); 600 sts &= (I2CMAL_BIT | I2CMCF_BIT | I2CMIF_BIT); 601 if (sts & I2CMAL_BIT) 602 adap->pch_event_flag |= I2CMAL_EVENT; 603 604 if (sts & I2CMCF_BIT) 605 adap->pch_event_flag |= I2CMCF_EVENT; 606 607 /* clear the applicable bits */ 608 pch_clrbit(adap->pch_base_address, PCH_I2CSR, sts); 609 610 pch_dbg(adap, "PCH_I2CSR = %x\n", ioread32(p + PCH_I2CSR)); 611 612 wake_up(&pch_event); 613} 614 615/** 616 * pch_i2c_handler() - interrupt handler for the PCH I2C controller 617 * @irq: irq number. 618 * @pData: cookie passed back to the handler function. 619 */ 620static irqreturn_t pch_i2c_handler(int irq, void *pData) 621{ 622 u32 reg_val; 623 int flag; 624 int i; 625 struct adapter_info *adap_info = pData; 626 void __iomem *p; 627 u32 mode; 628 629 for (i = 0, flag = 0; i < adap_info->ch_num; i++) { 630 p = adap_info->pch_data[i].pch_base_address; 631 mode = ioread32(p + PCH_I2CMOD); 632 mode &= BUFFER_MODE | EEPROM_SR_MODE; 633 if (mode != NORMAL_MODE) { 634 pch_err(adap_info->pch_data, 635 "I2C-%d mode(%d) is not supported\n", mode, i); 636 continue; 637 } 638 reg_val = ioread32(p + PCH_I2CSR); 639 if (reg_val & (I2CMAL_BIT | I2CMCF_BIT | I2CMIF_BIT)) { 640 pch_i2c_cb(&adap_info->pch_data[i]); 641 flag = 1; 642 } 643 } 644 645 return flag ? IRQ_HANDLED : IRQ_NONE; 646} 647 648/** 649 * pch_i2c_xfer() - Reading adnd writing data through I2C bus 650 * @i2c_adap: Pointer to the struct i2c_adapter. 651 * @msgs: Pointer to i2c_msg structure. 652 * @num: number of messages. 653 */ 654static s32 pch_i2c_xfer(struct i2c_adapter *i2c_adap, 655 struct i2c_msg *msgs, s32 num) 656{ 657 struct i2c_msg *pmsg; 658 u32 i = 0; 659 u32 status; 660 s32 ret; 661 662 struct i2c_algo_pch_data *adap = i2c_adap->algo_data; 663 664 ret = mutex_lock_interruptible(&pch_mutex); 665 if (ret) 666 return ret; 667 668 if (adap->p_adapter_info->pch_i2c_suspended) { 669 mutex_unlock(&pch_mutex); 670 return -EBUSY; 671 } 672 673 pch_dbg(adap, "adap->p_adapter_info->pch_i2c_suspended is %d\n", 674 adap->p_adapter_info->pch_i2c_suspended); 675 /* transfer not completed */ 676 adap->pch_i2c_xfer_in_progress = true; 677 678 for (i = 0; i < num && ret >= 0; i++) { 679 pmsg = &msgs[i]; 680 pmsg->flags |= adap->pch_buff_mode_en; 681 status = pmsg->flags; 682 pch_dbg(adap, 683 "After invoking I2C_MODE_SEL :flag= 0x%x\n", status); 684 685 if ((status & (I2C_M_RD)) != false) { 686 ret = pch_i2c_readbytes(i2c_adap, pmsg, (i + 1 == num), 687 (i == 0)); 688 } else { 689 ret = pch_i2c_writebytes(i2c_adap, pmsg, (i + 1 == num), 690 (i == 0)); 691 } 692 } 693 694 adap->pch_i2c_xfer_in_progress = false; /* transfer completed */ 695 696 mutex_unlock(&pch_mutex); 697 698 return (ret < 0) ? ret : num; 699} 700 701/** 702 * pch_i2c_func() - return the functionality of the I2C driver 703 * @adap: Pointer to struct i2c_algo_pch_data. 704 */ 705static u32 pch_i2c_func(struct i2c_adapter *adap) 706{ 707 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR; 708} 709 710static const struct i2c_algorithm pch_algorithm = { 711 .master_xfer = pch_i2c_xfer, 712 .functionality = pch_i2c_func 713}; 714 715/** 716 * pch_i2c_disbl_int() - Disable PCH I2C interrupts 717 * @adap: Pointer to struct i2c_algo_pch_data. 718 */ 719static void pch_i2c_disbl_int(struct i2c_algo_pch_data *adap) 720{ 721 void __iomem *p = adap->pch_base_address; 722 723 pch_clrbit(adap->pch_base_address, PCH_I2CCTL, NORMAL_INTR_ENBL); 724 725 iowrite32(EEPROM_RST_INTR_DISBL, p + PCH_I2CESRMSK); 726 727 iowrite32(BUFFER_MODE_INTR_DISBL, p + PCH_I2CBUFMSK); 728} 729 730static int pch_i2c_probe(struct pci_dev *pdev, 731 const struct pci_device_id *id) 732{ 733 void __iomem *base_addr; 734 int ret; 735 int i, j; 736 struct adapter_info *adap_info; 737 struct i2c_adapter *pch_adap; 738 739 pch_pci_dbg(pdev, "Entered.\n"); 740 741 adap_info = kzalloc((sizeof(struct adapter_info)), GFP_KERNEL); 742 if (adap_info == NULL) 743 return -ENOMEM; 744 745 ret = pci_enable_device(pdev); 746 if (ret) { 747 pch_pci_err(pdev, "pci_enable_device FAILED\n"); 748 goto err_pci_enable; 749 } 750 751 ret = pci_request_regions(pdev, KBUILD_MODNAME); 752 if (ret) { 753 pch_pci_err(pdev, "pci_request_regions FAILED\n"); 754 goto err_pci_req; 755 } 756 757 base_addr = pci_iomap(pdev, 1, 0); 758 759 if (base_addr == NULL) { 760 pch_pci_err(pdev, "pci_iomap FAILED\n"); 761 ret = -ENOMEM; 762 goto err_pci_iomap; 763 } 764 765 /* Set the number of I2C channel instance */ 766 adap_info->ch_num = id->driver_data; 767 768 for (i = 0; i < adap_info->ch_num; i++) { 769 pch_adap = &adap_info->pch_data[i].pch_adapter; 770 adap_info->pch_i2c_suspended = false; 771 772 adap_info->pch_data[i].p_adapter_info = adap_info; 773 774 pch_adap->owner = THIS_MODULE; 775 pch_adap->class = I2C_CLASS_HWMON; 776 strscpy(pch_adap->name, KBUILD_MODNAME, sizeof(pch_adap->name)); 777 pch_adap->algo = &pch_algorithm; 778 pch_adap->algo_data = &adap_info->pch_data[i]; 779 780 /* base_addr + offset; */ 781 adap_info->pch_data[i].pch_base_address = base_addr + 0x100 * i; 782 783 pch_adap->dev.of_node = pdev->dev.of_node; 784 pch_adap->dev.parent = &pdev->dev; 785 } 786 787 ret = request_irq(pdev->irq, pch_i2c_handler, IRQF_SHARED, 788 KBUILD_MODNAME, adap_info); 789 if (ret) { 790 pch_pci_err(pdev, "request_irq FAILED\n"); 791 goto err_request_irq; 792 } 793 794 for (i = 0; i < adap_info->ch_num; i++) { 795 pch_adap = &adap_info->pch_data[i].pch_adapter; 796 797 pch_i2c_init(&adap_info->pch_data[i]); 798 799 pch_adap->nr = i; 800 ret = i2c_add_numbered_adapter(pch_adap); 801 if (ret) { 802 pch_pci_err(pdev, "i2c_add_adapter[ch:%d] FAILED\n", i); 803 goto err_add_adapter; 804 } 805 } 806 807 pci_set_drvdata(pdev, adap_info); 808 pch_pci_dbg(pdev, "returns %d.\n", ret); 809 return 0; 810 811err_add_adapter: 812 for (j = 0; j < i; j++) 813 i2c_del_adapter(&adap_info->pch_data[j].pch_adapter); 814 free_irq(pdev->irq, adap_info); 815err_request_irq: 816 pci_iounmap(pdev, base_addr); 817err_pci_iomap: 818 pci_release_regions(pdev); 819err_pci_req: 820 pci_disable_device(pdev); 821err_pci_enable: 822 kfree(adap_info); 823 return ret; 824} 825 826static void pch_i2c_remove(struct pci_dev *pdev) 827{ 828 int i; 829 struct adapter_info *adap_info = pci_get_drvdata(pdev); 830 831 free_irq(pdev->irq, adap_info); 832 833 for (i = 0; i < adap_info->ch_num; i++) { 834 pch_i2c_disbl_int(&adap_info->pch_data[i]); 835 i2c_del_adapter(&adap_info->pch_data[i].pch_adapter); 836 } 837 838 if (adap_info->pch_data[0].pch_base_address) 839 pci_iounmap(pdev, adap_info->pch_data[0].pch_base_address); 840 841 for (i = 0; i < adap_info->ch_num; i++) 842 adap_info->pch_data[i].pch_base_address = NULL; 843 844 pci_release_regions(pdev); 845 846 pci_disable_device(pdev); 847 kfree(adap_info); 848} 849 850static int __maybe_unused pch_i2c_suspend(struct device *dev) 851{ 852 int i; 853 struct pci_dev *pdev = to_pci_dev(dev); 854 struct adapter_info *adap_info = pci_get_drvdata(pdev); 855 void __iomem *p = adap_info->pch_data[0].pch_base_address; 856 857 adap_info->pch_i2c_suspended = true; 858 859 for (i = 0; i < adap_info->ch_num; i++) { 860 while ((adap_info->pch_data[i].pch_i2c_xfer_in_progress)) { 861 /* Wait until all channel transfers are completed */ 862 msleep(20); 863 } 864 } 865 866 /* Disable the i2c interrupts */ 867 for (i = 0; i < adap_info->ch_num; i++) 868 pch_i2c_disbl_int(&adap_info->pch_data[i]); 869 870 pch_pci_dbg(pdev, "I2CSR = %x I2CBUFSTA = %x I2CESRSTA = %x " 871 "invoked function pch_i2c_disbl_int successfully\n", 872 ioread32(p + PCH_I2CSR), ioread32(p + PCH_I2CBUFSTA), 873 ioread32(p + PCH_I2CESRSTA)); 874 875 return 0; 876} 877 878static int __maybe_unused pch_i2c_resume(struct device *dev) 879{ 880 int i; 881 struct adapter_info *adap_info = dev_get_drvdata(dev); 882 883 for (i = 0; i < adap_info->ch_num; i++) 884 pch_i2c_init(&adap_info->pch_data[i]); 885 886 adap_info->pch_i2c_suspended = false; 887 888 return 0; 889} 890 891static SIMPLE_DEV_PM_OPS(pch_i2c_pm_ops, pch_i2c_suspend, pch_i2c_resume); 892 893static struct pci_driver pch_pcidriver = { 894 .name = KBUILD_MODNAME, 895 .id_table = pch_pcidev_id, 896 .probe = pch_i2c_probe, 897 .remove = pch_i2c_remove, 898 .driver.pm = &pch_i2c_pm_ops, 899}; 900 901module_pci_driver(pch_pcidriver); 902 903MODULE_DESCRIPTION("Intel EG20T PCH/LAPIS Semico ML7213/ML7223/ML7831 IOH I2C"); 904MODULE_LICENSE("GPL"); 905MODULE_AUTHOR("Tomoya MORINAGA. <tomoya.rohm@gmail.com>"); 906module_param(pch_i2c_speed, int, (S_IRUSR | S_IWUSR)); 907module_param(pch_clk, int, (S_IRUSR | S_IWUSR)); 908