+++ /dev/null
-/*
- * tsl2550.c - Linux kernel modules for ambient light sensor
- *
- * Copyright (C) 2007 Rodolfo Giometti <giometti@linux.it>
- * Copyright (C) 2007 Eurotech S.p.A. <info@eurotech.it>
- *
- * 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/module.h>
-#include <linux/init.h>
-#include <linux/slab.h>
-#include <linux/i2c.h>
-#include <linux/mutex.h>
-
-#define TSL2550_DRV_NAME "tsl2550"
-#define DRIVER_VERSION "1.2"
-
-/*
- * Defines
- */
-
-#define TSL2550_POWER_DOWN 0x00
-#define TSL2550_POWER_UP 0x03
-#define TSL2550_STANDARD_RANGE 0x18
-#define TSL2550_EXTENDED_RANGE 0x1d
-#define TSL2550_READ_ADC0 0x43
-#define TSL2550_READ_ADC1 0x83
-
-/*
- * Structs
- */
-
-struct tsl2550_data {
- struct i2c_client *client;
- struct mutex update_lock;
-
- unsigned int power_state : 1;
- unsigned int operating_mode : 1;
-};
-
-/*
- * Global data
- */
-
-static const u8 TSL2550_MODE_RANGE[2] = {
- TSL2550_STANDARD_RANGE, TSL2550_EXTENDED_RANGE,
-};
-
-/*
- * Management functions
- */
-
-static int tsl2550_set_operating_mode(struct i2c_client *client, int mode)
-{
- struct tsl2550_data *data = i2c_get_clientdata(client);
-
- int ret = i2c_smbus_write_byte(client, TSL2550_MODE_RANGE[mode]);
-
- data->operating_mode = mode;
-
- return ret;
-}
-
-static int tsl2550_set_power_state(struct i2c_client *client, int state)
-{
- struct tsl2550_data *data = i2c_get_clientdata(client);
- int ret;
-
- if (state == 0)
- ret = i2c_smbus_write_byte(client, TSL2550_POWER_DOWN);
- else {
- ret = i2c_smbus_write_byte(client, TSL2550_POWER_UP);
-
- /* On power up we should reset operating mode also... */
- tsl2550_set_operating_mode(client, data->operating_mode);
- }
-
- data->power_state = state;
-
- return ret;
-}
-
-static int tsl2550_get_adc_value(struct i2c_client *client, u8 cmd)
-{
- int ret;
-
- ret = i2c_smbus_read_byte_data(client, cmd);
- if (ret < 0)
- return ret;
- if (!(ret & 0x80))
- return -EAGAIN;
- return ret & 0x7f; /* remove the "valid" bit */
-}
-
-/*
- * LUX calculation
- */
-
-#define TSL2550_MAX_LUX 1846
-
-static const u8 ratio_lut[] = {
- 100, 100, 100, 100, 100, 100, 100, 100,
- 100, 100, 100, 100, 100, 100, 99, 99,
- 99, 99, 99, 99, 99, 99, 99, 99,
- 99, 99, 99, 98, 98, 98, 98, 98,
- 98, 98, 97, 97, 97, 97, 97, 96,
- 96, 96, 96, 95, 95, 95, 94, 94,
- 93, 93, 93, 92, 92, 91, 91, 90,
- 89, 89, 88, 87, 87, 86, 85, 84,
- 83, 82, 81, 80, 79, 78, 77, 75,
- 74, 73, 71, 69, 68, 66, 64, 62,
- 60, 58, 56, 54, 52, 49, 47, 44,
- 42, 41, 40, 40, 39, 39, 38, 38,
- 37, 37, 37, 36, 36, 36, 35, 35,
- 35, 35, 34, 34, 34, 34, 33, 33,
- 33, 33, 32, 32, 32, 32, 32, 31,
- 31, 31, 31, 31, 30, 30, 30, 30,
- 30,
-};
-
-static const u16 count_lut[] = {
- 0, 1, 2, 3, 4, 5, 6, 7,
- 8, 9, 10, 11, 12, 13, 14, 15,
- 16, 18, 20, 22, 24, 26, 28, 30,
- 32, 34, 36, 38, 40, 42, 44, 46,
- 49, 53, 57, 61, 65, 69, 73, 77,
- 81, 85, 89, 93, 97, 101, 105, 109,
- 115, 123, 131, 139, 147, 155, 163, 171,
- 179, 187, 195, 203, 211, 219, 227, 235,
- 247, 263, 279, 295, 311, 327, 343, 359,
- 375, 391, 407, 423, 439, 455, 471, 487,
- 511, 543, 575, 607, 639, 671, 703, 735,
- 767, 799, 831, 863, 895, 927, 959, 991,
- 1039, 1103, 1167, 1231, 1295, 1359, 1423, 1487,
- 1551, 1615, 1679, 1743, 1807, 1871, 1935, 1999,
- 2095, 2223, 2351, 2479, 2607, 2735, 2863, 2991,
- 3119, 3247, 3375, 3503, 3631, 3759, 3887, 4015,
-};
-
-/*
- * This function is described into Taos TSL2550 Designer's Notebook
- * pages 2, 3.
- */
-static int tsl2550_calculate_lux(u8 ch0, u8 ch1)
-{
- unsigned int lux;
-
- /* Look up count from channel values */
- u16 c0 = count_lut[ch0];
- u16 c1 = count_lut[ch1];
-
- /*
- * Calculate ratio.
- * Note: the "128" is a scaling factor
- */
- u8 r = 128;
-
- /* Avoid division by 0 and count 1 cannot be greater than count 0 */
- if (c1 <= c0)
- if (c0) {
- r = c1 * 128 / c0;
-
- /* Calculate LUX */
- lux = ((c0 - c1) * ratio_lut[r]) / 256;
- } else
- lux = 0;
- else
- return -EAGAIN;
-
- /* LUX range check */
- return lux > TSL2550_MAX_LUX ? TSL2550_MAX_LUX : lux;
-}
-
-/*
- * SysFS support
- */
-
-static ssize_t tsl2550_show_power_state(struct device *dev,
- struct device_attribute *attr, char *buf)
-{
- struct tsl2550_data *data = i2c_get_clientdata(to_i2c_client(dev));
-
- return sprintf(buf, "%u\n", data->power_state);
-}
-
-static ssize_t tsl2550_store_power_state(struct device *dev,
- struct device_attribute *attr, const char *buf, size_t count)
-{
- struct i2c_client *client = to_i2c_client(dev);
- struct tsl2550_data *data = i2c_get_clientdata(client);
- unsigned long val = simple_strtoul(buf, NULL, 10);
- int ret;
-
- if (val < 0 || val > 1)
- return -EINVAL;
-
- mutex_lock(&data->update_lock);
- ret = tsl2550_set_power_state(client, val);
- mutex_unlock(&data->update_lock);
-
- if (ret < 0)
- return ret;
-
- return count;
-}
-
-static DEVICE_ATTR(power_state, S_IWUSR | S_IRUGO,
- tsl2550_show_power_state, tsl2550_store_power_state);
-
-static ssize_t tsl2550_show_operating_mode(struct device *dev,
- struct device_attribute *attr, char *buf)
-{
- struct tsl2550_data *data = i2c_get_clientdata(to_i2c_client(dev));
-
- return sprintf(buf, "%u\n", data->operating_mode);
-}
-
-static ssize_t tsl2550_store_operating_mode(struct device *dev,
- struct device_attribute *attr, const char *buf, size_t count)
-{
- struct i2c_client *client = to_i2c_client(dev);
- struct tsl2550_data *data = i2c_get_clientdata(client);
- unsigned long val = simple_strtoul(buf, NULL, 10);
- int ret;
-
- if (val < 0 || val > 1)
- return -EINVAL;
-
- if (data->power_state == 0)
- return -EBUSY;
-
- mutex_lock(&data->update_lock);
- ret = tsl2550_set_operating_mode(client, val);
- mutex_unlock(&data->update_lock);
-
- if (ret < 0)
- return ret;
-
- return count;
-}
-
-static DEVICE_ATTR(operating_mode, S_IWUSR | S_IRUGO,
- tsl2550_show_operating_mode, tsl2550_store_operating_mode);
-
-static ssize_t __tsl2550_show_lux(struct i2c_client *client, char *buf)
-{
- struct tsl2550_data *data = i2c_get_clientdata(client);
- u8 ch0, ch1;
- int ret;
-
- ret = tsl2550_get_adc_value(client, TSL2550_READ_ADC0);
- if (ret < 0)
- return ret;
- ch0 = ret;
-
- ret = tsl2550_get_adc_value(client, TSL2550_READ_ADC1);
- if (ret < 0)
- return ret;
- ch1 = ret;
-
- /* Do the job */
- ret = tsl2550_calculate_lux(ch0, ch1);
- if (ret < 0)
- return ret;
- if (data->operating_mode == 1)
- ret *= 5;
-
- return sprintf(buf, "%d\n", ret);
-}
-
-static ssize_t tsl2550_show_lux1_input(struct device *dev,
- struct device_attribute *attr, char *buf)
-{
- struct i2c_client *client = to_i2c_client(dev);
- struct tsl2550_data *data = i2c_get_clientdata(client);
- int ret;
-
- /* No LUX data if not operational */
- if (!data->power_state)
- return -EBUSY;
-
- mutex_lock(&data->update_lock);
- ret = __tsl2550_show_lux(client, buf);
- mutex_unlock(&data->update_lock);
-
- return ret;
-}
-
-static DEVICE_ATTR(lux1_input, S_IRUGO,
- tsl2550_show_lux1_input, NULL);
-
-static struct attribute *tsl2550_attributes[] = {
- &dev_attr_power_state.attr,
- &dev_attr_operating_mode.attr,
- &dev_attr_lux1_input.attr,
- NULL
-};
-
-static const struct attribute_group tsl2550_attr_group = {
- .attrs = tsl2550_attributes,
-};
-
-/*
- * Initialization function
- */
-
-static int tsl2550_init_client(struct i2c_client *client)
-{
- struct tsl2550_data *data = i2c_get_clientdata(client);
- int err;
-
- /*
- * Probe the chip. To do so we try to power up the device and then to
- * read back the 0x03 code
- */
- err = i2c_smbus_read_byte_data(client, TSL2550_POWER_UP);
- if (err < 0)
- return err;
- if (err != TSL2550_POWER_UP)
- return -ENODEV;
- data->power_state = 1;
-
- /* Set the default operating mode */
- err = i2c_smbus_write_byte(client,
- TSL2550_MODE_RANGE[data->operating_mode]);
- if (err < 0)
- return err;
-
- return 0;
-}
-
-/*
- * I2C init/probing/exit functions
- */
-
-static struct i2c_driver tsl2550_driver;
-static int __devinit tsl2550_probe(struct i2c_client *client,
- const struct i2c_device_id *id)
-{
- struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
- struct tsl2550_data *data;
- int *opmode, err = 0;
-
- if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WRITE_BYTE
- | I2C_FUNC_SMBUS_READ_BYTE_DATA)) {
- err = -EIO;
- goto exit;
- }
-
- data = kzalloc(sizeof(struct tsl2550_data), GFP_KERNEL);
- if (!data) {
- err = -ENOMEM;
- goto exit;
- }
- data->client = client;
- i2c_set_clientdata(client, data);
-
- /* Check platform data */
- opmode = client->dev.platform_data;
- if (opmode) {
- if (*opmode < 0 || *opmode > 1) {
- dev_err(&client->dev, "invalid operating_mode (%d)\n",
- *opmode);
- err = -EINVAL;
- goto exit_kfree;
- }
- data->operating_mode = *opmode;
- } else
- data->operating_mode = 0; /* default mode is standard */
- dev_info(&client->dev, "%s operating mode\n",
- data->operating_mode ? "extended" : "standard");
-
- mutex_init(&data->update_lock);
-
- /* Initialize the TSL2550 chip */
- err = tsl2550_init_client(client);
- if (err)
- goto exit_kfree;
-
- /* Register sysfs hooks */
- err = sysfs_create_group(&client->dev.kobj, &tsl2550_attr_group);
- if (err)
- goto exit_kfree;
-
- dev_info(&client->dev, "support ver. %s enabled\n", DRIVER_VERSION);
-
- return 0;
-
-exit_kfree:
- kfree(data);
-exit:
- return err;
-}
-
-static int __devexit tsl2550_remove(struct i2c_client *client)
-{
- sysfs_remove_group(&client->dev.kobj, &tsl2550_attr_group);
-
- /* Power down the device */
- tsl2550_set_power_state(client, 0);
-
- kfree(i2c_get_clientdata(client));
-
- return 0;
-}
-
-#ifdef CONFIG_PM
-
-static int tsl2550_suspend(struct i2c_client *client, pm_message_t mesg)
-{
- return tsl2550_set_power_state(client, 0);
-}
-
-static int tsl2550_resume(struct i2c_client *client)
-{
- return tsl2550_set_power_state(client, 1);
-}
-
-#else
-
-#define tsl2550_suspend NULL
-#define tsl2550_resume NULL
-
-#endif /* CONFIG_PM */
-
-static const struct i2c_device_id tsl2550_id[] = {
- { "tsl2550", 0 },
- { }
-};
-MODULE_DEVICE_TABLE(i2c, tsl2550_id);
-
-static struct i2c_driver tsl2550_driver = {
- .driver = {
- .name = TSL2550_DRV_NAME,
- .owner = THIS_MODULE,
- },
- .suspend = tsl2550_suspend,
- .resume = tsl2550_resume,
- .probe = tsl2550_probe,
- .remove = __devexit_p(tsl2550_remove),
- .id_table = tsl2550_id,
-};
-
-static int __init tsl2550_init(void)
-{
- return i2c_add_driver(&tsl2550_driver);
-}
-
-static void __exit tsl2550_exit(void)
-{
- i2c_del_driver(&tsl2550_driver);
-}
-
-MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
-MODULE_DESCRIPTION("TSL2550 ambient light sensor driver");
-MODULE_LICENSE("GPL");
-MODULE_VERSION(DRIVER_VERSION);
-
-module_init(tsl2550_init);
-module_exit(tsl2550_exit);
git.openpandora.org / pandora-kernel.git / blobdiff