--- /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/i2c.h>
+#include <linux/i2c-sensor.h>
+#include <linux/i2c-vid.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 };
+static unsigned int normal_isa[] = { I2C_CLIENT_ISA_END };
+
+SENSORS_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 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 ((jiffies - data->last_updated > HZ) ||
+ (jiffies < data->last_updated) ||
+ !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 */
+ssize_t atxp1_showvcore(struct device *dev, 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;
+}
+
+ssize_t atxp1_storevcore(struct device *dev, 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_info(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 */
+ssize_t atxp1_showgpio1(struct device *dev, 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;
+}
+
+ssize_t atxp1_storegpio1(struct device *dev, 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 */
+ssize_t atxp1_showgpio2(struct device *dev, char *buf)
+{
+ int size;
+ struct atxp1_data *data;
+
+ data = atxp1_update_device(dev);
+
+ size = sprintf(buf, "0x%02x\n", data->reg.gpio2);
+
+ return size;
+}
+
+ssize_t atxp1_storegpio2(struct device *dev, 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)
+{
+ return i2c_detect(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 = kmalloc(sizeof(struct atxp1_data), GFP_KERNEL))) {
+ err = -ENOMEM;
+ goto exit;
+ }
+
+ memset(data, 0, sizeof(struct atxp1_data));
+ 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 = i2c_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;
+ }
+
+ 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_free:
+ kfree(data);
+exit:
+ return err;
+};
+
+static int atxp1_detach_client(struct i2c_client * client)
+{
+ int err;
+
+ err = i2c_detach_client(client);
+
+ if (err)
+ dev_err(&client->dev, "Failed to detach client.\n");
+ else
+ kfree(i2c_get_clientdata(client));
+
+ 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);
projects / GitHub / moto-9609 / android_kernel_motorola_exynos9610.git / commitdiff