--- /dev/null
+/*
+ * 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>
+#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
+
+static const unsigned short normal_i2c[] = { 0x37, 0x4e, I2C_CLIENT_END };
+
+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 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 = 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(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 = 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(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 = 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(gpio2, S_IRUGO | S_IWUSR, atxp1_showgpio2, atxp1_storegpio2);
+
+static struct attribute *atxp1_attrs[] = {
+ &dev_attr_gpio1.attr,
+ &dev_attr_gpio2.attr,
+ &dev_attr_cpu0_vid.attr,
+ NULL
+};
+ATTRIBUTE_GROUPS(atxp1);
+
+/* Return 0 if detection is successful, -ENODEV otherwise */
+static int atxp1_detect(struct i2c_client *new_client,
+ struct i2c_board_info *info)
+{
+ struct i2c_adapter *adapter = new_client->adapter;
+
+ u8 temp;
+
+ if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
+ return -ENODEV;
+
+ /* 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)))
+ return -ENODEV;
+
+ /*
+ * 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)))
+ return -ENODEV;
+
+ /* Get VRM */
+ temp = vid_which_vrm();
+
+ if ((temp != 90) && (temp != 91)) {
+ dev_err(&adapter->dev, "atxp1: Not supporting VRM %d.%d\n",
+ temp / 10, temp % 10);
+ return -ENODEV;
+ }
+
+ strlcpy(info->type, "atxp1", I2C_NAME_SIZE);
+
+ return 0;
+}
+
+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();
+
+ 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,
+ .detect = atxp1_detect,
+ .address_list = normal_i2c,
+};
+
+module_i2c_driver(atxp1_driver);
Code Review / kvmfornfv.git / blobdiff