/* i2c-via.c - Part of lm_sensors, Linux kernel modules for hardware monitoring i2c Support for Via Technologies 82C586B South Bridge Copyright (c) 1998, 1999 Ky�sti M�lkki <kmalkki@cc.hut.fi> This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include <linux/config.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/pci.h> #include <linux/ioport.h> #include <linux/init.h> #include <linux/i2c.h> #include <linux/i2c-algo-bit.h> #include <asm/io.h> /* Power management registers */ #define PM_CFG_REVID 0x08 /* silicon revision code */ #define PM_CFG_IOBASE0 0x20 #define PM_CFG_IOBASE1 0x48 #define I2C_DIR (pm_io_base+0x40) #define I2C_OUT (pm_io_base+0x42) #define I2C_IN (pm_io_base+0x44) #define I2C_SCL 0x02 /* clock bit in DIR/OUT/IN register */ #define I2C_SDA 0x04 /* io-region reservation */ #define IOSPACE 0x06 #define IOTEXT "via-i2c" static u16 pm_io_base = 0; /* It does not appear from the datasheet that the GPIO pins are open drain. So a we set a low value by setting the direction to output and a high value by setting the direction to input and relying on the required I2C pullup. The data value is initialized to 0 in via_init() and never changed. */ static void bit_via_setscl(void *data, int state) { outb(state ? inb(I2C_DIR) & ~I2C_SCL : inb(I2C_DIR) | I2C_SCL, I2C_DIR); } static void bit_via_setsda(void *data, int state) { outb(state ? inb(I2C_DIR) & ~I2C_SDA : inb(I2C_DIR) | I2C_SDA, I2C_DIR); } static int bit_via_getscl(void *data) { return (0 != (inb(I2C_IN) & I2C_SCL)); } static int bit_via_getsda(void *data) { return (0 != (inb(I2C_IN) & I2C_SDA)); } static struct i2c_algo_bit_data bit_data = { .setsda = bit_via_setsda, .setscl = bit_via_setscl, .getsda = bit_via_getsda, .getscl = bit_via_getscl, .udelay = 5, .mdelay = 5, .timeout = HZ }; static struct i2c_adapter vt586b_adapter = { .owner = THIS_MODULE, .class = I2C_CLASS_HWMON, .name = "VIA i2c", .algo_data = &bit_data, }; static struct pci_device_id vt586b_ids[] __devinitdata = { { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C586_3) }, { 0, } }; MODULE_DEVICE_TABLE (pci, vt586b_ids); static int __devinit vt586b_probe(struct pci_dev *dev, const struct pci_device_id *id) { u16 base; u8 rev; int res; if (pm_io_base) { dev_err(&dev->dev, "i2c-via: Will only support one host\n"); return -ENODEV; } pci_read_config_byte(dev, PM_CFG_REVID, &rev); switch (rev) { case 0x00: base = PM_CFG_IOBASE0; break; case 0x01: case 0x10: base = PM_CFG_IOBASE1; break; default: base = PM_CFG_IOBASE1; /* later revision */ } pci_read_config_word(dev, base, &pm_io_base); pm_io_base &= (0xff << 8); if (!request_region(I2C_DIR, IOSPACE, IOTEXT)) { dev_err(&dev->dev, "IO 0x%x-0x%x already in use\n", I2C_DIR, I2C_DIR + IOSPACE); return -ENODEV; } outb(inb(I2C_DIR) & ~(I2C_SDA | I2C_SCL), I2C_DIR); outb(inb(I2C_OUT) & ~(I2C_SDA | I2C_SCL), I2C_OUT); /* set up the driverfs linkage to our parent device */ vt586b_adapter.dev.parent = &dev->dev; res = i2c_bit_add_bus(&vt586b_adapter); if ( res < 0 ) { release_region(I2C_DIR, IOSPACE); pm_io_base = 0; return res; } return 0; } static void __devexit vt586b_remove(struct pci_dev *dev) { i2c_bit_del_bus(&vt586b_adapter); release_region(I2C_DIR, IOSPACE); pm_io_base = 0; } static struct pci_driver vt586b_driver = { .name = "vt586b_smbus", .id_table = vt586b_ids, .probe = vt586b_probe, .remove = __devexit_p(vt586b_remove), }; static int __init i2c_vt586b_init(void) { return pci_register_driver(&vt586b_driver); } static void __exit i2c_vt586b_exit(void) { pci_unregister_driver(&vt586b_driver); } MODULE_AUTHOR("Ky�sti M�lkki <kmalkki@cc.hut.fi>"); MODULE_DESCRIPTION("i2c for Via vt82c586b southbridge"); MODULE_LICENSE("GPL"); module_init(i2c_vt586b_init); module_exit(i2c_vt586b_exit);