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Diffstat (limited to '')
| -rw-r--r-- | drivers/hwmon/atxp1.c | 304 |
1 files changed, 304 insertions, 0 deletions
diff --git a/drivers/hwmon/atxp1.c b/drivers/hwmon/atxp1.c new file mode 100644 index 000000000..b7eadb54c --- /dev/null +++ b/drivers/hwmon/atxp1.c @@ -0,0 +1,304 @@ +/* + * 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. + * + * The ATXP1 can reside on I2C addresses 0x37 or 0x4e. The chip is + * not auto-detected by the driver and must be instantiated explicitly. + * See Documentation/i2c/instantiating-devices for more information. + */ + +#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> +#include <linux/mutex.h> +#include <linux/sysfs.h> +#include <linux/slab.h> + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("System voltages control via Attansic ATXP1"); +MODULE_VERSION("0.6.3"); +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 + +struct atxp1_data { + struct i2c_client *client; + struct mutex 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 atxp1_data *data = dev_get_drvdata(dev); + struct i2c_client *client = data->client; + + mutex_lock(&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; + } + + mutex_unlock(&data->update_lock); + + return data; +} + +/* sys file functions for cpu0_vid */ +static ssize_t cpu0_vid_show(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 cpu0_vid_store(struct device *dev, + struct device_attribute *attr, const char *buf, + size_t count) +{ + struct atxp1_data *data = atxp1_update_device(dev); + struct i2c_client *client = data->client; + int vid, cvid; + unsigned long vcore; + int err; + + err = kstrtoul(buf, 10, &vcore); + if (err) + return err; + + vcore /= 25; + vcore *= 25; + + /* Calculate VID */ + vid = vid_to_reg(vcore, data->vrm); + if (vid < 0) { + dev_err(dev, "VID calculation failed.\n"); + return vid; + } + + /* + * 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", (int)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_RW(cpu0_vid); + +/* sys file functions for GPIO1 */ +static ssize_t gpio1_show(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 gpio1_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct atxp1_data *data = atxp1_update_device(dev); + struct i2c_client *client = data->client; + unsigned long value; + int err; + + err = kstrtoul(buf, 16, &value); + if (err) + return err; + + value &= ATXP1_GPIO1MASK; + + if (value != (data->reg.gpio1 & ATXP1_GPIO1MASK)) { + dev_info(dev, "Writing 0x%x to GPIO1.\n", (unsigned int)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_RW(gpio1); + +/* sys file functions for GPIO2 */ +static ssize_t gpio2_show(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 gpio2_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct atxp1_data *data = atxp1_update_device(dev); + struct i2c_client *client = data->client; + unsigned long value; + int err; + + err = kstrtoul(buf, 16, &value); + if (err) + return err; + value &= 0xff; + + if (value != data->reg.gpio2) { + dev_info(dev, "Writing 0x%x to GPIO1.\n", (unsigned int)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_RW(gpio2); + +static struct attribute *atxp1_attrs[] = { + &dev_attr_gpio1.attr, + &dev_attr_gpio2.attr, + &dev_attr_cpu0_vid.attr, + NULL +}; +ATTRIBUTE_GROUPS(atxp1); + +static int atxp1_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct device *dev = &client->dev; + struct atxp1_data *data; + struct device *hwmon_dev; + + data = devm_kzalloc(dev, sizeof(struct atxp1_data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + /* Get VRM */ + data->vrm = vid_which_vrm(); + if (data->vrm != 90 && data->vrm != 91) { + dev_err(dev, "atxp1: Not supporting VRM %d.%d\n", + data->vrm / 10, data->vrm % 10); + return -ENODEV; + } + + data->client = client; + mutex_init(&data->update_lock); + + hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name, + data, + atxp1_groups); + if (IS_ERR(hwmon_dev)) + return PTR_ERR(hwmon_dev); + + dev_info(dev, "Using VRM: %d.%d\n", data->vrm / 10, data->vrm % 10); + + return 0; +}; + +static const struct i2c_device_id atxp1_id[] = { + { "atxp1", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, atxp1_id); + +static struct i2c_driver atxp1_driver = { + .class = I2C_CLASS_HWMON, + .driver = { + .name = "atxp1", + }, + .probe = atxp1_probe, + .id_table = atxp1_id, +}; + +module_i2c_driver(atxp1_driver); |