/* atxp1.c - kernel module for setting CPU VID and general purpose I/Os using the Attansic ATXP1 chip. 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/kernel.h> #include <linux/init.h> #include <linux/module.h> #include <linux/jiffies.h> #include <linux/i2c.h> #include <linux/hwmon.h> #include <linux/hwmon-vid.h> #include <linux/err.h> MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("System voltages control via Attansic ATXP1"); MODULE_VERSION("0.6.2"); MODULE_AUTHOR("Sebastian Witt <se.witt@gmx.net>"); #define ATXP1_VID 0x00 #define ATXP1_CVID 0x01 #define ATXP1_GPIO1 0x06 #define ATXP1_GPIO2 0x0a #define ATXP1_VIDENA 0x20 #define ATXP1_VIDMASK 0x1f #define ATXP1_GPIO1MASK 0x0f static unsigned short normal_i2c[] = { 0x37, 0x4e, I2C_CLIENT_END }; I2C_CLIENT_INSMOD_1(atxp1); static int atxp1_attach_adapter(struct i2c_adapter * adapter); static int atxp1_detach_client(struct i2c_client * client); static struct atxp1_data * atxp1_update_device(struct device *dev); static int atxp1_detect(struct i2c_adapter *adapter, int address, int kind); static struct i2c_driver atxp1_driver = { .owner = THIS_MODULE, .name = "atxp1", .flags = I2C_DF_NOTIFY, .attach_adapter = atxp1_attach_adapter, .detach_client = atxp1_detach_client, }; struct atxp1_data { struct i2c_client client; struct class_device *class_dev; struct semaphore update_lock; unsigned long last_updated; u8 valid; struct { u8 vid; /* VID output register */ u8 cpu_vid; /* VID input from CPU */ u8 gpio1; /* General purpose I/O register 1 */ u8 gpio2; /* General purpose I/O register 2 */ } reg; u8 vrm; /* Detected CPU VRM */ }; static struct atxp1_data * atxp1_update_device(struct device *dev) { struct i2c_client *client; struct atxp1_data *data; client = to_i2c_client(dev); data = i2c_get_clientdata(client); down(&data->update_lock); if (time_after(jiffies, data->last_updated + HZ) || !data->valid) { /* Update local register data */ data->reg.vid = i2c_smbus_read_byte_data(client, ATXP1_VID); data->reg.cpu_vid = i2c_smbus_read_byte_data(client, ATXP1_CVID); data->reg.gpio1 = i2c_smbus_read_byte_data(client, ATXP1_GPIO1); data->reg.gpio2 = i2c_smbus_read_byte_data(client, ATXP1_GPIO2); data->valid = 1; } up(&data->update_lock); return(data); } /* sys file functions for cpu0_vid */ static ssize_t atxp1_showvcore(struct device *dev, struct device_attribute *attr, char *buf) { int size; struct atxp1_data *data; data = atxp1_update_device(dev); size = sprintf(buf, "%d\n", vid_from_reg(data->reg.vid & ATXP1_VIDMASK, data->vrm)); return size; } static ssize_t atxp1_storevcore(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct atxp1_data *data; struct i2c_client *client; char vid; char cvid; unsigned int vcore; client = to_i2c_client(dev); data = atxp1_update_device(dev); vcore = simple_strtoul(buf, NULL, 10); vcore /= 25; vcore *= 25; /* Calculate VID */ vid = vid_to_reg(vcore, data->vrm); if (vid < 0) { dev_err(dev, "VID calculation failed.\n"); return -1; } /* If output enabled, use control register value. Otherwise original CPU VID */ if (data->reg.vid & ATXP1_VIDENA) cvid = data->reg.vid & ATXP1_VIDMASK; else cvid = data->reg.cpu_vid; /* Nothing changed, aborting */ if (vid == cvid) return count; dev_dbg(dev, "Setting VCore to %d mV (0x%02x)\n", vcore, vid); /* Write every 25 mV step to increase stability */ if (cvid > vid) { for (; cvid >= vid; cvid--) { i2c_smbus_write_byte_data(client, ATXP1_VID, cvid | ATXP1_VIDENA); } } else { for (; cvid <= vid; cvid++) { i2c_smbus_write_byte_data(client, ATXP1_VID, cvid | ATXP1_VIDENA); } } data->valid = 0; return count; } /* CPU core reference voltage unit: millivolt */ static DEVICE_ATTR(cpu0_vid, S_IRUGO | S_IWUSR, atxp1_showvcore, atxp1_storevcore); /* sys file functions for GPIO1 */ static ssize_t atxp1_showgpio1(struct device *dev, struct device_attribute *attr, char *buf) { int size; struct atxp1_data *data; data = atxp1_update_device(dev); size = sprintf(buf, "0x%02x\n", data->reg.gpio1 & ATXP1_GPIO1MASK); return size; } static ssize_t atxp1_storegpio1(struct device *dev, struct device_attribute *attr, const char*buf, size_t count) { struct atxp1_data *data; struct i2c_client *client; unsigned int value; client = to_i2c_client(dev); data = atxp1_update_device(dev); value = simple_strtoul(buf, NULL, 16); value &= ATXP1_GPIO1MASK; if (value != (data->reg.gpio1 & ATXP1_GPIO1MASK)) { dev_info(dev, "Writing 0x%x to GPIO1.\n", value); i2c_smbus_write_byte_data(client, ATXP1_GPIO1, value); data->valid = 0; } return count; } /* GPIO1 data register unit: Four bit as hex (e.g. 0x0f) */ static DEVICE_ATTR(gpio1, S_IRUGO | S_IWUSR, atxp1_showgpio1, atxp1_storegpio1); /* sys file functions for GPIO2 */ static ssize_t atxp1_showgpio2(struct device *dev, struct device_attribute *attr, char *buf) { int size; struct atxp1_data *data; data = atxp1_update_device(dev); size = sprintf(buf, "0x%02x\n", data->reg.gpio2); return size; } static ssize_t atxp1_storegpio2(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct atxp1_data *data; struct i2c_client *client; unsigned int value; client = to_i2c_client(dev); data = atxp1_update_device(dev); value = simple_strtoul(buf, NULL, 16) & 0xff; if (value != data->reg.gpio2) { dev_info(dev, "Writing 0x%x to GPIO1.\n", value); i2c_smbus_write_byte_data(client, ATXP1_GPIO2, value); data->valid = 0; } return count; } /* GPIO2 data register unit: Eight bit as hex (e.g. 0xff) */ static DEVICE_ATTR(gpio2, S_IRUGO | S_IWUSR, atxp1_showgpio2, atxp1_storegpio2); static int atxp1_attach_adapter(struct i2c_adapter *adapter) { if (!(adapter->class & I2C_CLASS_HWMON)) return 0; return i2c_probe(adapter, &addr_data, &atxp1_detect); }; static int atxp1_detect(struct i2c_adapter *adapter, int address, int kind) { struct i2c_client * new_client; struct atxp1_data * data; int err = 0; u8 temp; if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) goto exit; if (!(data = kzalloc(sizeof(struct atxp1_data), GFP_KERNEL))) { err = -ENOMEM; goto exit; } new_client = &data->client; i2c_set_clientdata(new_client, data); new_client->addr = address; new_client->adapter = adapter; new_client->driver = &atxp1_driver; new_client->flags = 0; /* Detect ATXP1, checking if vendor ID registers are all zero */ if (!((i2c_smbus_read_byte_data(new_client, 0x3e) == 0) && (i2c_smbus_read_byte_data(new_client, 0x3f) == 0) && (i2c_smbus_read_byte_data(new_client, 0xfe) == 0) && (i2c_smbus_read_byte_data(new_client, 0xff) == 0) )) { /* No vendor ID, now checking if registers 0x10,0x11 (non-existent) * showing the same as register 0x00 */ temp = i2c_smbus_read_byte_data(new_client, 0x00); if (!((i2c_smbus_read_byte_data(new_client, 0x10) == temp) && (i2c_smbus_read_byte_data(new_client, 0x11) == temp) )) goto exit_free; } /* Get VRM */ data->vrm = vid_which_vrm(); if ((data->vrm != 90) && (data->vrm != 91)) { dev_err(&new_client->dev, "Not supporting VRM %d.%d\n", data->vrm / 10, data->vrm % 10); goto exit_free; } strncpy(new_client->name, "atxp1", I2C_NAME_SIZE); data->valid = 0; init_MUTEX(&data->update_lock); err = i2c_attach_client(new_client); if (err) { dev_err(&new_client->dev, "Attach client error.\n"); goto exit_free; } data->class_dev = hwmon_device_register(&new_client->dev); if (IS_ERR(data->class_dev)) { err = PTR_ERR(data->class_dev); goto exit_detach; } device_create_file(&new_client->dev, &dev_attr_gpio1); device_create_file(&new_client->dev, &dev_attr_gpio2); device_create_file(&new_client->dev, &dev_attr_cpu0_vid); dev_info(&new_client->dev, "Using VRM: %d.%d\n", data->vrm / 10, data->vrm % 10); return 0; exit_detach: i2c_detach_client(new_client); exit_free: kfree(data); exit: return err; }; static int atxp1_detach_client(struct i2c_client * client) { struct atxp1_data * data = i2c_get_clientdata(client); int err; hwmon_device_unregister(data->class_dev); err = i2c_detach_client(client); if (err) dev_err(&client->dev, "Failed to detach client.\n"); else kfree(data); return err; }; static int __init atxp1_init(void) { return i2c_add_driver(&atxp1_driver); }; static void __exit atxp1_exit(void) { i2c_del_driver(&atxp1_driver); }; module_init(atxp1_init); module_exit(atxp1_exit);