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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 Copyright (c) 2002,2003 Alexander Malysh <amalysh@web.de>4 5*/6 7/*8 Status: beta9 10 Supports:11 SIS 63012 SIS 73013 SIS 96414 15 Notable differences between chips:16 +------------------------+--------------------+-------------------+17 | | SIS630/730 | SIS964 |18 +------------------------+--------------------+-------------------+19 | Clock | 14kHz/56kHz | 55.56kHz/27.78kHz |20 | SMBus registers offset | 0x80 | 0xE0 |21 | SMB_CNT | Bit 1 = Slave Busy | Bit 1 = Bus probe |22 | (not used yet) | Bit 3 is reserved | Bit 3 = Last byte |23 | SMB_PCOUNT | Offset + 0x06 | Offset + 0x14 |24 | SMB_COUNT | 4:0 bits | 5:0 bits |25 +------------------------+--------------------+-------------------+26 (Other differences don't affect the functions provided by the driver)27 28 Note: we assume there can only be one device, with one SMBus interface.29*/30 31#include <linux/kernel.h>32#include <linux/module.h>33#include <linux/delay.h>34#include <linux/pci.h>35#include <linux/ioport.h>36#include <linux/i2c.h>37#include <linux/acpi.h>38#include <linux/io.h>39 40/* SIS964 id is defined here as we are the only file using it */41#define PCI_DEVICE_ID_SI_964 0x096442 43/* SIS630/730/964 SMBus registers */44#define SMB_STS 0x00 /* status */45#define SMB_CNT 0x02 /* control */46#define SMBHOST_CNT 0x03 /* host control */47#define SMB_ADDR 0x04 /* address */48#define SMB_CMD 0x05 /* command */49#define SMB_COUNT 0x07 /* byte count */50#define SMB_BYTE 0x08 /* ~0x8F data byte field */51 52/* SMB_STS register */53#define BYTE_DONE_STS 0x10 /* Byte Done Status / Block Array */54#define SMBCOL_STS 0x04 /* Collision */55#define SMBERR_STS 0x02 /* Device error */56 57/* SMB_CNT register */58#define MSTO_EN 0x40 /* Host Master Timeout Enable */59#define SMBCLK_SEL 0x20 /* Host master clock selection */60#define SMB_PROBE 0x02 /* Bus Probe/Slave busy */61#define SMB_HOSTBUSY 0x01 /* Host Busy */62 63/* SMBHOST_CNT register */64#define SMB_KILL 0x20 /* Kill */65#define SMB_START 0x10 /* Start */66 67/* register count for request_region68 * As we don't use SMB_PCOUNT, 20 is ok for SiS630 and SiS96469 */70#define SIS630_SMB_IOREGION 2071 72/* PCI address constants */73/* acpi base address register */74#define SIS630_ACPI_BASE_REG 0x7475/* bios control register */76#define SIS630_BIOS_CTL_REG 0x4077 78/* Other settings */79#define MAX_TIMEOUT 50080 81/* SIS630 constants */82#define SIS630_QUICK 0x0083#define SIS630_BYTE 0x0184#define SIS630_BYTE_DATA 0x0285#define SIS630_WORD_DATA 0x0386#define SIS630_PCALL 0x0487#define SIS630_BLOCK_DATA 0x0588 89static struct pci_driver sis630_driver;90 91/* insmod parameters */92static bool high_clock;93static bool force;94module_param(high_clock, bool, 0);95MODULE_PARM_DESC(high_clock,96 "Set Host Master Clock to 56KHz (default 14KHz) (SIS630/730 only).");97module_param(force, bool, 0);98MODULE_PARM_DESC(force, "Forcibly enable the SIS630. DANGEROUS!");99 100/* SMBus base address */101static unsigned short smbus_base;102 103/* supported chips */104static int supported[] = {105 PCI_DEVICE_ID_SI_630,106 PCI_DEVICE_ID_SI_730,107 PCI_DEVICE_ID_SI_760,108 0 /* terminates the list */109};110 111static inline u8 sis630_read(u8 reg)112{113 return inb(smbus_base + reg);114}115 116static inline void sis630_write(u8 reg, u8 data)117{118 outb(data, smbus_base + reg);119}120 121static int sis630_transaction_start(struct i2c_adapter *adap, int size,122 u8 *oldclock)123{124 int temp;125 126 /* Make sure the SMBus host is ready to start transmitting. */127 temp = sis630_read(SMB_CNT);128 if ((temp & (SMB_PROBE | SMB_HOSTBUSY)) != 0x00) {129 dev_dbg(&adap->dev, "SMBus busy (%02x). Resetting...\n", temp);130 /* kill smbus transaction */131 sis630_write(SMBHOST_CNT, SMB_KILL);132 133 temp = sis630_read(SMB_CNT);134 if (temp & (SMB_PROBE | SMB_HOSTBUSY)) {135 dev_dbg(&adap->dev, "Failed! (%02x)\n", temp);136 return -EBUSY;137 } else {138 dev_dbg(&adap->dev, "Successful!\n");139 }140 }141 142 /* save old clock, so we can prevent machine for hung */143 *oldclock = sis630_read(SMB_CNT);144 145 dev_dbg(&adap->dev, "saved clock 0x%02x\n", *oldclock);146 147 /* disable timeout interrupt,148 * set Host Master Clock to 56KHz if requested */149 if (high_clock)150 sis630_write(SMB_CNT, SMBCLK_SEL);151 else152 sis630_write(SMB_CNT, (*oldclock & ~MSTO_EN));153 154 /* clear all sticky bits */155 temp = sis630_read(SMB_STS);156 sis630_write(SMB_STS, temp & 0x1e);157 158 /* start the transaction by setting bit 4 and size */159 sis630_write(SMBHOST_CNT, SMB_START | (size & 0x07));160 161 return 0;162}163 164static int sis630_transaction_wait(struct i2c_adapter *adap, int size)165{166 int temp, result = 0, timeout = 0;167 168 /* We will always wait for a fraction of a second! */169 do {170 msleep(1);171 temp = sis630_read(SMB_STS);172 /* check if block transmitted */173 if (size == SIS630_BLOCK_DATA && (temp & BYTE_DONE_STS))174 break;175 } while (!(temp & 0x0e) && (timeout++ < MAX_TIMEOUT));176 177 /* If the SMBus is still busy, we give up */178 if (timeout > MAX_TIMEOUT) {179 dev_dbg(&adap->dev, "SMBus Timeout!\n");180 result = -ETIMEDOUT;181 }182 183 if (temp & SMBERR_STS) {184 dev_dbg(&adap->dev, "Error: Failed bus transaction\n");185 result = -ENXIO;186 }187 188 if (temp & SMBCOL_STS) {189 dev_err(&adap->dev, "Bus collision!\n");190 result = -EAGAIN;191 }192 193 return result;194}195 196static void sis630_transaction_end(struct i2c_adapter *adap, u8 oldclock)197{198 /* clear all status "sticky" bits */199 sis630_write(SMB_STS, 0xFF);200 201 dev_dbg(&adap->dev,202 "SMB_CNT before clock restore 0x%02x\n", sis630_read(SMB_CNT));203 204 /*205 * restore old Host Master Clock if high_clock is set206 * and oldclock was not 56KHz207 */208 if (high_clock && !(oldclock & SMBCLK_SEL))209 sis630_write(SMB_CNT, sis630_read(SMB_CNT) & ~SMBCLK_SEL);210 211 dev_dbg(&adap->dev,212 "SMB_CNT after clock restore 0x%02x\n", sis630_read(SMB_CNT));213}214 215static int sis630_transaction(struct i2c_adapter *adap, int size)216{217 int result = 0;218 u8 oldclock = 0;219 220 result = sis630_transaction_start(adap, size, &oldclock);221 if (!result) {222 result = sis630_transaction_wait(adap, size);223 sis630_transaction_end(adap, oldclock);224 }225 226 return result;227}228 229static int sis630_block_data(struct i2c_adapter *adap,230 union i2c_smbus_data *data, int read_write)231{232 int i, len = 0, rc = 0;233 u8 oldclock = 0;234 235 if (read_write == I2C_SMBUS_WRITE) {236 len = data->block[0];237 if (len < 0)238 len = 0;239 else if (len > 32)240 len = 32;241 sis630_write(SMB_COUNT, len);242 for (i = 1; i <= len; i++) {243 dev_dbg(&adap->dev,244 "set data 0x%02x\n", data->block[i]);245 /* set data */246 sis630_write(SMB_BYTE + (i - 1) % 8, data->block[i]);247 if (i == 8 || (len < 8 && i == len)) {248 dev_dbg(&adap->dev,249 "start trans len=%d i=%d\n", len, i);250 /* first transaction */251 rc = sis630_transaction_start(adap,252 SIS630_BLOCK_DATA, &oldclock);253 if (rc)254 return rc;255 } else if ((i - 1) % 8 == 7 || i == len) {256 dev_dbg(&adap->dev,257 "trans_wait len=%d i=%d\n", len, i);258 if (i > 8) {259 dev_dbg(&adap->dev,260 "clear smbary_sts"261 " len=%d i=%d\n", len, i);262 /*263 If this is not first transaction,264 we must clear sticky bit.265 clear SMBARY_STS266 */267 sis630_write(SMB_STS, BYTE_DONE_STS);268 }269 rc = sis630_transaction_wait(adap,270 SIS630_BLOCK_DATA);271 if (rc) {272 dev_dbg(&adap->dev,273 "trans_wait failed\n");274 break;275 }276 }277 }278 } else {279 /* read request */280 data->block[0] = len = 0;281 rc = sis630_transaction_start(adap,282 SIS630_BLOCK_DATA, &oldclock);283 if (rc)284 return rc;285 do {286 rc = sis630_transaction_wait(adap, SIS630_BLOCK_DATA);287 if (rc) {288 dev_dbg(&adap->dev, "trans_wait failed\n");289 break;290 }291 /* if this first transaction then read byte count */292 if (len == 0)293 data->block[0] = sis630_read(SMB_COUNT);294 295 /* just to be sure */296 if (data->block[0] > 32)297 data->block[0] = 32;298 299 dev_dbg(&adap->dev,300 "block data read len=0x%x\n", data->block[0]);301 302 for (i = 0; i < 8 && len < data->block[0]; i++, len++) {303 dev_dbg(&adap->dev,304 "read i=%d len=%d\n", i, len);305 data->block[len + 1] = sis630_read(SMB_BYTE +306 i);307 }308 309 dev_dbg(&adap->dev,310 "clear smbary_sts len=%d i=%d\n", len, i);311 312 /* clear SMBARY_STS */313 sis630_write(SMB_STS, BYTE_DONE_STS);314 } while (len < data->block[0]);315 }316 317 sis630_transaction_end(adap, oldclock);318 319 return rc;320}321 322/* Return negative errno on error. */323static s32 sis630_access(struct i2c_adapter *adap, u16 addr,324 unsigned short flags, char read_write,325 u8 command, int size, union i2c_smbus_data *data)326{327 int status;328 329 switch (size) {330 case I2C_SMBUS_QUICK:331 sis630_write(SMB_ADDR,332 ((addr & 0x7f) << 1) | (read_write & 0x01));333 size = SIS630_QUICK;334 break;335 case I2C_SMBUS_BYTE:336 sis630_write(SMB_ADDR,337 ((addr & 0x7f) << 1) | (read_write & 0x01));338 if (read_write == I2C_SMBUS_WRITE)339 sis630_write(SMB_CMD, command);340 size = SIS630_BYTE;341 break;342 case I2C_SMBUS_BYTE_DATA:343 sis630_write(SMB_ADDR,344 ((addr & 0x7f) << 1) | (read_write & 0x01));345 sis630_write(SMB_CMD, command);346 if (read_write == I2C_SMBUS_WRITE)347 sis630_write(SMB_BYTE, data->byte);348 size = SIS630_BYTE_DATA;349 break;350 case I2C_SMBUS_PROC_CALL:351 case I2C_SMBUS_WORD_DATA:352 sis630_write(SMB_ADDR,353 ((addr & 0x7f) << 1) | (read_write & 0x01));354 sis630_write(SMB_CMD, command);355 if (read_write == I2C_SMBUS_WRITE) {356 sis630_write(SMB_BYTE, data->word & 0xff);357 sis630_write(SMB_BYTE + 1, (data->word & 0xff00) >> 8);358 }359 size = (size == I2C_SMBUS_PROC_CALL ?360 SIS630_PCALL : SIS630_WORD_DATA);361 break;362 case I2C_SMBUS_BLOCK_DATA:363 sis630_write(SMB_ADDR,364 ((addr & 0x7f) << 1) | (read_write & 0x01));365 sis630_write(SMB_CMD, command);366 size = SIS630_BLOCK_DATA;367 return sis630_block_data(adap, data, read_write);368 default:369 dev_warn(&adap->dev, "Unsupported transaction %d\n", size);370 return -EOPNOTSUPP;371 }372 373 status = sis630_transaction(adap, size);374 if (status)375 return status;376 377 if ((size != SIS630_PCALL) &&378 ((read_write == I2C_SMBUS_WRITE) || (size == SIS630_QUICK))) {379 return 0;380 }381 382 switch (size) {383 case SIS630_BYTE:384 case SIS630_BYTE_DATA:385 data->byte = sis630_read(SMB_BYTE);386 break;387 case SIS630_PCALL:388 case SIS630_WORD_DATA:389 data->word = sis630_read(SMB_BYTE) +390 (sis630_read(SMB_BYTE + 1) << 8);391 break;392 }393 394 return 0;395}396 397static u32 sis630_func(struct i2c_adapter *adapter)398{399 return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |400 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |401 I2C_FUNC_SMBUS_PROC_CALL | I2C_FUNC_SMBUS_BLOCK_DATA;402}403 404static int sis630_setup(struct pci_dev *sis630_dev)405{406 unsigned char b;407 struct pci_dev *dummy = NULL;408 int retval, i;409 /* acpi base address */410 unsigned short acpi_base;411 412 /* check for supported SiS devices */413 for (i = 0; supported[i] > 0; i++) {414 dummy = pci_get_device(PCI_VENDOR_ID_SI, supported[i], dummy);415 if (dummy)416 break; /* found */417 }418 419 if (dummy) {420 pci_dev_put(dummy);421 } else if (force) {422 dev_err(&sis630_dev->dev,423 "WARNING: Can't detect SIS630 compatible device, but "424 "loading because of force option enabled\n");425 } else {426 return -ENODEV;427 }428 429 /*430 Enable ACPI first , so we can accsess reg 74-75431 in acpi io space and read acpi base addr432 */433 if (pci_read_config_byte(sis630_dev, SIS630_BIOS_CTL_REG, &b)) {434 dev_err(&sis630_dev->dev, "Error: Can't read bios ctl reg\n");435 retval = -ENODEV;436 goto exit;437 }438 /* if ACPI already enabled , do nothing */439 if (!(b & 0x80) &&440 pci_write_config_byte(sis630_dev, SIS630_BIOS_CTL_REG, b | 0x80)) {441 dev_err(&sis630_dev->dev, "Error: Can't enable ACPI\n");442 retval = -ENODEV;443 goto exit;444 }445 446 /* Determine the ACPI base address */447 if (pci_read_config_word(sis630_dev,448 SIS630_ACPI_BASE_REG, &acpi_base)) {449 dev_err(&sis630_dev->dev,450 "Error: Can't determine ACPI base address\n");451 retval = -ENODEV;452 goto exit;453 }454 455 dev_dbg(&sis630_dev->dev, "ACPI base at 0x%04hx\n", acpi_base);456 457 if (supported[i] == PCI_DEVICE_ID_SI_760)458 smbus_base = acpi_base + 0xE0;459 else460 smbus_base = acpi_base + 0x80;461 462 dev_dbg(&sis630_dev->dev, "SMBus base at 0x%04hx\n", smbus_base);463 464 retval = acpi_check_region(smbus_base + SMB_STS, SIS630_SMB_IOREGION,465 sis630_driver.name);466 if (retval)467 goto exit;468 469 /* Everything is happy, let's grab the memory and set things up. */470 if (!request_region(smbus_base + SMB_STS, SIS630_SMB_IOREGION,471 sis630_driver.name)) {472 dev_err(&sis630_dev->dev,473 "I/O Region 0x%04x-0x%04x for SMBus already in use.\n",474 smbus_base + SMB_STS,475 smbus_base + SMB_STS + SIS630_SMB_IOREGION - 1);476 retval = -EBUSY;477 goto exit;478 }479 480 retval = 0;481 482exit:483 if (retval)484 smbus_base = 0;485 return retval;486}487 488 489static const struct i2c_algorithm smbus_algorithm = {490 .smbus_xfer = sis630_access,491 .functionality = sis630_func,492};493 494static struct i2c_adapter sis630_adapter = {495 .owner = THIS_MODULE,496 .class = I2C_CLASS_HWMON,497 .algo = &smbus_algorithm,498 .retries = 3499};500 501static const struct pci_device_id sis630_ids[] = {502 { PCI_DEVICE(PCI_VENDOR_ID_SI, PCI_DEVICE_ID_SI_503) },503 { PCI_DEVICE(PCI_VENDOR_ID_SI, PCI_DEVICE_ID_SI_LPC) },504 { PCI_DEVICE(PCI_VENDOR_ID_SI, PCI_DEVICE_ID_SI_964) },505 { 0, }506};507 508MODULE_DEVICE_TABLE(pci, sis630_ids);509 510static int sis630_probe(struct pci_dev *dev, const struct pci_device_id *id)511{512 if (sis630_setup(dev)) {513 dev_err(&dev->dev,514 "SIS630 compatible bus not detected, "515 "module not inserted.\n");516 return -ENODEV;517 }518 519 /* set up the sysfs linkage to our parent device */520 sis630_adapter.dev.parent = &dev->dev;521 522 snprintf(sis630_adapter.name, sizeof(sis630_adapter.name),523 "SMBus SIS630 adapter at %04x", smbus_base + SMB_STS);524 525 return i2c_add_adapter(&sis630_adapter);526}527 528static void sis630_remove(struct pci_dev *dev)529{530 if (smbus_base) {531 i2c_del_adapter(&sis630_adapter);532 release_region(smbus_base + SMB_STS, SIS630_SMB_IOREGION);533 smbus_base = 0;534 }535}536 537 538static struct pci_driver sis630_driver = {539 .name = "sis630_smbus",540 .id_table = sis630_ids,541 .probe = sis630_probe,542 .remove = sis630_remove,543};544 545module_pci_driver(sis630_driver);546 547MODULE_LICENSE("GPL");548MODULE_AUTHOR("Alexander Malysh <amalysh@web.de>");549MODULE_DESCRIPTION("SIS630 SMBus driver");550