// SPDX-License-Identifier: GPL-2.0-or-later /* Copyright (c) 2002,2003 Alexander Malysh <amalysh@web.de> */ /* Status: beta Supports: SIS 630 SIS 730 SIS 964 Notable differences between chips: +------------------------+--------------------+-------------------+ | | SIS630/730 | SIS964 | +------------------------+--------------------+-------------------+ | Clock | 14kHz/56kHz | 55.56kHz/27.78kHz | | SMBus registers offset | 0x80 | 0xE0 | | SMB_CNT | Bit 1 = Slave Busy | Bit 1 = Bus probe | | (not used yet) | Bit 3 is reserved | Bit 3 = Last byte | | SMB_PCOUNT | Offset + 0x06 | Offset + 0x14 | | SMB_COUNT | 4:0 bits | 5:0 bits | +------------------------+--------------------+-------------------+ (Other differences don't affect the functions provided by the driver) Note: we assume there can only be one device, with one SMBus interface. */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/delay.h> #include <linux/pci.h> #include <linux/ioport.h> #include <linux/i2c.h> #include <linux/acpi.h> #include <linux/io.h> /* SIS964 id is defined here as we are the only file using it */ #define PCI_DEVICE_ID_SI_964 0x0964 /* SIS630/730/964 SMBus registers */ #define SMB_STS 0x00 /* status */ #define SMB_CNT 0x02 /* control */ #define SMBHOST_CNT 0x03 /* host control */ #define SMB_ADDR 0x04 /* address */ #define SMB_CMD 0x05 /* command */ #define SMB_COUNT 0x07 /* byte count */ #define SMB_BYTE 0x08 /* ~0x8F data byte field */ /* SMB_STS register */ #define BYTE_DONE_STS 0x10 /* Byte Done Status / Block Array */ #define SMBCOL_STS 0x04 /* Collision */ #define SMBERR_STS 0x02 /* Device error */ /* SMB_CNT register */ #define MSTO_EN 0x40 /* Host Master Timeout Enable */ #define SMBCLK_SEL 0x20 /* Host master clock selection */ #define SMB_PROBE 0x02 /* Bus Probe/Slave busy */ #define SMB_HOSTBUSY 0x01 /* Host Busy */ /* SMBHOST_CNT register */ #define SMB_KILL 0x20 /* Kill */ #define SMB_START 0x10 /* Start */ /* register count for request_region * As we don't use SMB_PCOUNT, 20 is ok for SiS630 and SiS964 */ #define SIS630_SMB_IOREGION 20 /* PCI address constants */ /* acpi base address register */ #define SIS630_ACPI_BASE_REG 0x74 /* bios control register */ #define SIS630_BIOS_CTL_REG 0x40 /* Other settings */ #define MAX_TIMEOUT 500 /* SIS630 constants */ #define SIS630_QUICK 0x00 #define SIS630_BYTE 0x01 #define SIS630_BYTE_DATA 0x02 #define SIS630_WORD_DATA 0x03 #define SIS630_PCALL 0x04 #define SIS630_BLOCK_DATA 0x05 static struct pci_driver sis630_driver; /* insmod parameters */ static bool high_clock; static bool force; module_param(high_clock, bool, 0); MODULE_PARM_DESC(high_clock, "Set Host Master Clock to 56KHz (default 14KHz) (SIS630/730 only)."); module_param(force, bool, 0); MODULE_PARM_DESC(force, "Forcibly enable the SIS630. DANGEROUS!"); /* SMBus base adress */ static unsigned short smbus_base; /* supported chips */ static int supported[] = { PCI_DEVICE_ID_SI_630, PCI_DEVICE_ID_SI_730, PCI_DEVICE_ID_SI_760, 0 /* terminates the list */ }; static inline u8 sis630_read(u8 reg) { return inb(smbus_base + reg); } static inline void sis630_write(u8 reg, u8 data) { outb(data, smbus_base + reg); } static int sis630_transaction_start(struct i2c_adapter *adap, int size, u8 *oldclock) { int temp; /* Make sure the SMBus host is ready to start transmitting. */ temp = sis630_read(SMB_CNT); if ((temp & (SMB_PROBE | SMB_HOSTBUSY)) != 0x00) { dev_dbg(&adap->dev, "SMBus busy (%02x). Resetting...\n", temp); /* kill smbus transaction */ sis630_write(SMBHOST_CNT, SMB_KILL); temp = sis630_read(SMB_CNT); if (temp & (SMB_PROBE | SMB_HOSTBUSY)) { dev_dbg(&adap->dev, "Failed! (%02x)\n", temp); return -EBUSY; } else { dev_dbg(&adap->dev, "Successful!\n"); } } /* save old clock, so we can prevent machine for hung */ *oldclock = sis630_read(SMB_CNT); dev_dbg(&adap->dev, "saved clock 0x%02x\n", *oldclock); /* disable timeout interrupt, * set Host Master Clock to 56KHz if requested */ if (high_clock) sis630_write(SMB_CNT, SMBCLK_SEL); else sis630_write(SMB_CNT, (*oldclock & ~MSTO_EN)); /* clear all sticky bits */ temp = sis630_read(SMB_STS); sis630_write(SMB_STS, temp & 0x1e); /* start the transaction by setting bit 4 and size */ sis630_write(SMBHOST_CNT, SMB_START | (size & 0x07)); return 0; } static int sis630_transaction_wait(struct i2c_adapter *adap, int size) { int temp, result = 0, timeout = 0; /* We will always wait for a fraction of a second! */ do { msleep(1); temp = sis630_read(SMB_STS); /* check if block transmitted */ if (size == SIS630_BLOCK_DATA && (temp & BYTE_DONE_STS)) break; } while (!(temp & 0x0e) && (timeout++ < MAX_TIMEOUT)); /* If the SMBus is still busy, we give up */ if (timeout > MAX_TIMEOUT) { dev_dbg(&adap->dev, "SMBus Timeout!\n"); result = -ETIMEDOUT; } if (temp & SMBERR_STS) { dev_dbg(&adap->dev, "Error: Failed bus transaction\n"); result = -ENXIO; } if (temp & SMBCOL_STS) { dev_err(&adap->dev, "Bus collision!\n"); result = -EAGAIN; } return result; } static void sis630_transaction_end(struct i2c_adapter *adap, u8 oldclock) { /* clear all status "sticky" bits */ sis630_write(SMB_STS, 0xFF); dev_dbg(&adap->dev, "SMB_CNT before clock restore 0x%02x\n", sis630_read(SMB_CNT)); /* * restore old Host Master Clock if high_clock is set * and oldclock was not 56KHz */ if (high_clock && !(oldclock & SMBCLK_SEL)) sis630_write(SMB_CNT, sis630_read(SMB_CNT) & ~SMBCLK_SEL); dev_dbg(&adap->dev, "SMB_CNT after clock restore 0x%02x\n", sis630_read(SMB_CNT)); } static int sis630_transaction(struct i2c_adapter *adap, int size) { int result = 0; u8 oldclock = 0; result = sis630_transaction_start(adap, size, &oldclock); if (!result) { result = sis630_transaction_wait(adap, size); sis630_transaction_end(adap, oldclock); } return result; } static int sis630_block_data(struct i2c_adapter *adap, union i2c_smbus_data *data, int read_write) { int i, len = 0, rc = 0; u8 oldclock = 0; if (read_write == I2C_SMBUS_WRITE) { len = data->block[0]; if (len < 0) len = 0; else if (len > 32) len = 32; sis630_write(SMB_COUNT, len); for (i = 1; i <= len; i++) { dev_dbg(&adap->dev, "set data 0x%02x\n", data->block[i]); /* set data */ sis630_write(SMB_BYTE + (i - 1) % 8, data->block[i]); if (i == 8 || (len < 8 && i == len)) { dev_dbg(&adap->dev, "start trans len=%d i=%d\n", len, i); /* first transaction */ rc = sis630_transaction_start(adap, SIS630_BLOCK_DATA, &oldclock); if (rc) return rc; } else if ((i - 1) % 8 == 7 || i == len) { dev_dbg(&adap->dev, "trans_wait len=%d i=%d\n", len, i); if (i > 8) { dev_dbg(&adap->dev, "clear smbary_sts" " len=%d i=%d\n", len, i); /* If this is not first transaction, we must clear sticky bit. clear SMBARY_STS */ sis630_write(SMB_STS, BYTE_DONE_STS); } rc = sis630_transaction_wait(adap, SIS630_BLOCK_DATA); if (rc) { dev_dbg(&adap->dev, "trans_wait failed\n"); break; } } } } else { /* read request */ data->block[0] = len = 0; rc = sis630_transaction_start(adap, SIS630_BLOCK_DATA, &oldclock); if (rc) return rc; do { rc = sis630_transaction_wait(adap, SIS630_BLOCK_DATA); if (rc) { dev_dbg(&adap->dev, "trans_wait failed\n"); break; } /* if this first transaction then read byte count */ if (len == 0) data->block[0] = sis630_read(SMB_COUNT); /* just to be sure */ if (data->block[0] > 32) data->block[0] = 32; dev_dbg(&adap->dev, "block data read len=0x%x\n", data->block[0]); for (i = 0; i < 8 && len < data->block[0]; i++, len++) { dev_dbg(&adap->dev, "read i=%d len=%d\n", i, len); data->block[len + 1] = sis630_read(SMB_BYTE + i); } dev_dbg(&adap->dev, "clear smbary_sts len=%d i=%d\n", len, i); /* clear SMBARY_STS */ sis630_write(SMB_STS, BYTE_DONE_STS); } while (len < data->block[0]); } sis630_transaction_end(adap, oldclock); return rc; } /* Return negative errno on error. */ static s32 sis630_access(struct i2c_adapter *adap, u16 addr, unsigned short flags, char read_write, u8 command, int size, union i2c_smbus_data *data) { int status; switch (size) { case I2C_SMBUS_QUICK: sis630_write(SMB_ADDR, ((addr & 0x7f) << 1) | (read_write & 0x01)); size = SIS630_QUICK; break; case I2C_SMBUS_BYTE: sis630_write(SMB_ADDR, ((addr & 0x7f) << 1) | (read_write & 0x01)); if (read_write == I2C_SMBUS_WRITE) sis630_write(SMB_CMD, command); size = SIS630_BYTE; break; case I2C_SMBUS_BYTE_DATA: sis630_write(SMB_ADDR, ((addr & 0x7f) << 1) | (read_write & 0x01)); sis630_write(SMB_CMD, command); if (read_write == I2C_SMBUS_WRITE) sis630_write(SMB_BYTE, data->byte); size = SIS630_BYTE_DATA; break; case I2C_SMBUS_PROC_CALL: case I2C_SMBUS_WORD_DATA: sis630_write(SMB_ADDR, ((addr & 0x7f) << 1) | (read_write & 0x01)); sis630_write(SMB_CMD, command); if (read_write == I2C_SMBUS_WRITE) { sis630_write(SMB_BYTE, data->word & 0xff); sis630_write(SMB_BYTE + 1, (data->word & 0xff00) >> 8); } size = (size == I2C_SMBUS_PROC_CALL ? SIS630_PCALL : SIS630_WORD_DATA); break; case I2C_SMBUS_BLOCK_DATA: sis630_write(SMB_ADDR, ((addr & 0x7f) << 1) | (read_write & 0x01)); sis630_write(SMB_CMD, command); size = SIS630_BLOCK_DATA; return sis630_block_data(adap, data, read_write); default: dev_warn(&adap->dev, "Unsupported transaction %d\n", size); return -EOPNOTSUPP; } status = sis630_transaction(adap, size); if (status) return status; if ((size != SIS630_PCALL) && ((read_write == I2C_SMBUS_WRITE) || (size == SIS630_QUICK))) { return 0; } switch (size) { case SIS630_BYTE: case SIS630_BYTE_DATA: data->byte = sis630_read(SMB_BYTE); break; case SIS630_PCALL: case SIS630_WORD_DATA: data->word = sis630_read(SMB_BYTE) + (sis630_read(SMB_BYTE + 1) << 8); break; } return 0; } static u32 sis630_func(struct i2c_adapter *adapter) { return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_PROC_CALL | I2C_FUNC_SMBUS_BLOCK_DATA; } static int sis630_setup(struct pci_dev *sis630_dev) { unsigned char b; struct pci_dev *dummy = NULL; int retval, i; /* acpi base address */ unsigned short acpi_base; /* check for supported SiS devices */ for (i = 0; supported[i] > 0; i++) { dummy = pci_get_device(PCI_VENDOR_ID_SI, supported[i], dummy); if (dummy) break; /* found */ } if (dummy) { pci_dev_put(dummy); } else if (force) { dev_err(&sis630_dev->dev, "WARNING: Can't detect SIS630 compatible device, but " "loading because of force option enabled\n"); } else { return -ENODEV; } /* Enable ACPI first , so we can accsess reg 74-75 in acpi io space and read acpi base addr */ if (pci_read_config_byte(sis630_dev, SIS630_BIOS_CTL_REG, &b)) { dev_err(&sis630_dev->dev, "Error: Can't read bios ctl reg\n"); retval = -ENODEV; goto exit; } /* if ACPI already enabled , do nothing */ if (!(b & 0x80) && pci_write_config_byte(sis630_dev, SIS630_BIOS_CTL_REG, b | 0x80)) { dev_err(&sis630_dev->dev, "Error: Can't enable ACPI\n"); retval = -ENODEV; goto exit; } /* Determine the ACPI base address */ if (pci_read_config_word(sis630_dev, SIS630_ACPI_BASE_REG, &acpi_base)) { dev_err(&sis630_dev->dev, "Error: Can't determine ACPI base address\n"); retval = -ENODEV; goto exit; } dev_dbg(&sis630_dev->dev, "ACPI base at 0x%04hx\n", acpi_base); if (supported[i] == PCI_DEVICE_ID_SI_760) smbus_base = acpi_base + 0xE0; else smbus_base = acpi_base + 0x80; dev_dbg(&sis630_dev->dev, "SMBus base at 0x%04hx\n", smbus_base); retval = acpi_check_region(smbus_base + SMB_STS, SIS630_SMB_IOREGION, sis630_driver.name); if (retval) goto exit; /* Everything is happy, let's grab the memory and set things up. */ if (!request_region(smbus_base + SMB_STS, SIS630_SMB_IOREGION, sis630_driver.name)) { dev_err(&sis630_dev->dev, "I/O Region 0x%04x-0x%04x for SMBus already in use.\n", smbus_base + SMB_STS, smbus_base + SMB_STS + SIS630_SMB_IOREGION - 1); retval = -EBUSY; goto exit; } retval = 0; exit: if (retval) smbus_base = 0; return retval; } static const struct i2c_algorithm smbus_algorithm = { .smbus_xfer = sis630_access, .functionality = sis630_func, }; static struct i2c_adapter sis630_adapter = { .owner = THIS_MODULE, .class = I2C_CLASS_HWMON | I2C_CLASS_SPD, .algo = &smbus_algorithm, .retries = 3 }; static const struct pci_device_id sis630_ids[] = { { PCI_DEVICE(PCI_VENDOR_ID_SI, PCI_DEVICE_ID_SI_503) }, { PCI_DEVICE(PCI_VENDOR_ID_SI, PCI_DEVICE_ID_SI_LPC) }, { PCI_DEVICE(PCI_VENDOR_ID_SI, PCI_DEVICE_ID_SI_964) }, { 0, } }; MODULE_DEVICE_TABLE(pci, sis630_ids); static int sis630_probe(struct pci_dev *dev, const struct pci_device_id *id) { if (sis630_setup(dev)) { dev_err(&dev->dev, "SIS630 compatible bus not detected, " "module not inserted.\n"); return -ENODEV; } /* set up the sysfs linkage to our parent device */ sis630_adapter.dev.parent = &dev->dev; snprintf(sis630_adapter.name, sizeof(sis630_adapter.name), "SMBus SIS630 adapter at %04x", smbus_base + SMB_STS); return i2c_add_adapter(&sis630_adapter); } static void sis630_remove(struct pci_dev *dev) { if (smbus_base) { i2c_del_adapter(&sis630_adapter); release_region(smbus_base + SMB_STS, SIS630_SMB_IOREGION); smbus_base = 0; } } static struct pci_driver sis630_driver = { .name = "sis630_smbus", .id_table = sis630_ids, .probe = sis630_probe, .remove = sis630_remove, }; module_pci_driver(sis630_driver); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Alexander Malysh <amalysh@web.de>"); MODULE_DESCRIPTION("SIS630 SMBus driver");