diff options
Diffstat (limited to 'drivers/misc/isl29003.c')
| -rw-r--r-- | drivers/misc/isl29003.c | 470 |
1 files changed, 470 insertions, 0 deletions
diff --git a/drivers/misc/isl29003.c b/drivers/misc/isl29003.c new file mode 100644 index 000000000000..2e2a5923d4c2 --- /dev/null +++ b/drivers/misc/isl29003.c @@ -0,0 +1,470 @@ +/* + * isl29003.c - Linux kernel module for + * Intersil ISL29003 ambient light sensor + * + * See file:Documentation/misc-devices/isl29003 + * + * Copyright (c) 2009 Daniel Mack <daniel@caiaq.de> + * + * Based on code written by + * Rodolfo Giometti <giometti@linux.it> + * 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> +#include <linux/delay.h> + +#define ISL29003_DRV_NAME "isl29003" +#define DRIVER_VERSION "1.0" + +#define ISL29003_REG_COMMAND 0x00 +#define ISL29003_ADC_ENABLED (1 << 7) +#define ISL29003_ADC_PD (1 << 6) +#define ISL29003_TIMING_INT (1 << 5) +#define ISL29003_MODE_SHIFT (2) +#define ISL29003_MODE_MASK (0x3 << ISL29003_MODE_SHIFT) +#define ISL29003_RES_SHIFT (0) +#define ISL29003_RES_MASK (0x3 << ISL29003_RES_SHIFT) + +#define ISL29003_REG_CONTROL 0x01 +#define ISL29003_INT_FLG (1 << 5) +#define ISL29003_RANGE_SHIFT (2) +#define ISL29003_RANGE_MASK (0x3 << ISL29003_RANGE_SHIFT) +#define ISL29003_INT_PERSISTS_SHIFT (0) +#define ISL29003_INT_PERSISTS_MASK (0xf << ISL29003_INT_PERSISTS_SHIFT) + +#define ISL29003_REG_IRQ_THRESH_HI 0x02 +#define ISL29003_REG_IRQ_THRESH_LO 0x03 +#define ISL29003_REG_LSB_SENSOR 0x04 +#define ISL29003_REG_MSB_SENSOR 0x05 +#define ISL29003_REG_LSB_TIMER 0x06 +#define ISL29003_REG_MSB_TIMER 0x07 + +#define ISL29003_NUM_CACHABLE_REGS 4 + +struct isl29003_data { + struct i2c_client *client; + struct mutex lock; + u8 reg_cache[ISL29003_NUM_CACHABLE_REGS]; +}; + +static int gain_range[] = { + 1000, 4000, 16000, 64000 +}; + +/* + * register access helpers + */ + +static int __isl29003_read_reg(struct i2c_client *client, + u32 reg, u8 mask, u8 shift) +{ + struct isl29003_data *data = i2c_get_clientdata(client); + return (data->reg_cache[reg] & mask) >> shift; +} + +static int __isl29003_write_reg(struct i2c_client *client, + u32 reg, u8 mask, u8 shift, u8 val) +{ + struct isl29003_data *data = i2c_get_clientdata(client); + int ret = 0; + u8 tmp; + + if (reg >= ISL29003_NUM_CACHABLE_REGS) + return -EINVAL; + + mutex_lock(&data->lock); + + tmp = data->reg_cache[reg]; + tmp &= ~mask; + tmp |= val << shift; + + ret = i2c_smbus_write_byte_data(client, reg, tmp); + if (!ret) + data->reg_cache[reg] = tmp; + + mutex_unlock(&data->lock); + return ret; +} + +/* + * internally used functions + */ + +/* range */ +static int isl29003_get_range(struct i2c_client *client) +{ + return __isl29003_read_reg(client, ISL29003_REG_CONTROL, + ISL29003_RANGE_MASK, ISL29003_RANGE_SHIFT); +} + +static int isl29003_set_range(struct i2c_client *client, int range) +{ + return __isl29003_write_reg(client, ISL29003_REG_CONTROL, + ISL29003_RANGE_MASK, ISL29003_RANGE_SHIFT, range); +} + +/* resolution */ +static int isl29003_get_resolution(struct i2c_client *client) +{ + return __isl29003_read_reg(client, ISL29003_REG_COMMAND, + ISL29003_RES_MASK, ISL29003_RES_SHIFT); +} + +static int isl29003_set_resolution(struct i2c_client *client, int res) +{ + return __isl29003_write_reg(client, ISL29003_REG_COMMAND, + ISL29003_RES_MASK, ISL29003_RES_SHIFT, res); +} + +/* mode */ +static int isl29003_get_mode(struct i2c_client *client) +{ + return __isl29003_read_reg(client, ISL29003_REG_COMMAND, + ISL29003_RES_MASK, ISL29003_RES_SHIFT); +} + +static int isl29003_set_mode(struct i2c_client *client, int mode) +{ + return __isl29003_write_reg(client, ISL29003_REG_COMMAND, + ISL29003_RES_MASK, ISL29003_RES_SHIFT, mode); +} + +/* power_state */ +static int isl29003_set_power_state(struct i2c_client *client, int state) +{ + return __isl29003_write_reg(client, ISL29003_REG_COMMAND, + ISL29003_ADC_ENABLED | ISL29003_ADC_PD, 0, + state ? ISL29003_ADC_ENABLED : ISL29003_ADC_PD); +} + +static int isl29003_get_power_state(struct i2c_client *client) +{ + struct isl29003_data *data = i2c_get_clientdata(client); + u8 cmdreg = data->reg_cache[ISL29003_REG_COMMAND]; + return ~cmdreg & ISL29003_ADC_PD; +} + +static int isl29003_get_adc_value(struct i2c_client *client) +{ + struct isl29003_data *data = i2c_get_clientdata(client); + int lsb, msb, range, bitdepth; + + mutex_lock(&data->lock); + lsb = i2c_smbus_read_byte_data(client, ISL29003_REG_LSB_SENSOR); + + if (lsb < 0) { + mutex_unlock(&data->lock); + return lsb; + } + + msb = i2c_smbus_read_byte_data(client, ISL29003_REG_MSB_SENSOR); + mutex_unlock(&data->lock); + + if (msb < 0) + return msb; + + range = isl29003_get_range(client); + bitdepth = (4 - isl29003_get_resolution(client)) * 4; + return (((msb << 8) | lsb) * gain_range[range]) >> bitdepth; +} + +/* + * sysfs layer + */ + +/* range */ +static ssize_t isl29003_show_range(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct i2c_client *client = to_i2c_client(dev); + return sprintf(buf, "%i\n", isl29003_get_range(client)); +} + +static ssize_t isl29003_store_range(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct i2c_client *client = to_i2c_client(dev); + unsigned long val; + int ret; + + if ((strict_strtoul(buf, 10, &val) < 0) || (val > 3)) + return -EINVAL; + + ret = isl29003_set_range(client, val); + if (ret < 0) + return ret; + + return count; +} + +static DEVICE_ATTR(range, S_IWUSR | S_IRUGO, + isl29003_show_range, isl29003_store_range); + + +/* resolution */ +static ssize_t isl29003_show_resolution(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct i2c_client *client = to_i2c_client(dev); + return sprintf(buf, "%d\n", isl29003_get_resolution(client)); +} + +static ssize_t isl29003_store_resolution(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct i2c_client *client = to_i2c_client(dev); + unsigned long val; + int ret; + + if ((strict_strtoul(buf, 10, &val) < 0) || (val > 3)) + return -EINVAL; + + ret = isl29003_set_resolution(client, val); + if (ret < 0) + return ret; + + return count; +} + +static DEVICE_ATTR(resolution, S_IWUSR | S_IRUGO, + isl29003_show_resolution, isl29003_store_resolution); + +/* mode */ +static ssize_t isl29003_show_mode(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct i2c_client *client = to_i2c_client(dev); + return sprintf(buf, "%d\n", isl29003_get_mode(client)); +} + +static ssize_t isl29003_store_mode(struct device *dev, + struct device_attribute *attr, const char *buf, size_t count) +{ + struct i2c_client *client = to_i2c_client(dev); + unsigned long val; + int ret; + + if ((strict_strtoul(buf, 10, &val) < 0) || (val > 2)) + return -EINVAL; + + ret = isl29003_set_mode(client, val); + if (ret < 0) + return ret; + + return count; +} + +static DEVICE_ATTR(mode, S_IWUSR | S_IRUGO, + isl29003_show_mode, isl29003_store_mode); + + +/* power state */ +static ssize_t isl29003_show_power_state(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct i2c_client *client = to_i2c_client(dev); + return sprintf(buf, "%d\n", isl29003_get_power_state(client)); +} + +static ssize_t isl29003_store_power_state(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct i2c_client *client = to_i2c_client(dev); + unsigned long val; + int ret; + + if ((strict_strtoul(buf, 10, &val) < 0) || (val > 1)) + return -EINVAL; + + ret = isl29003_set_power_state(client, val); + return ret ? ret : count; +} + +static DEVICE_ATTR(power_state, S_IWUSR | S_IRUGO, + isl29003_show_power_state, isl29003_store_power_state); + + +/* lux */ +static ssize_t isl29003_show_lux(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct i2c_client *client = to_i2c_client(dev); + + /* No LUX data if not operational */ + if (!isl29003_get_power_state(client)) + return -EBUSY; + + return sprintf(buf, "%d\n", isl29003_get_adc_value(client)); +} + +static DEVICE_ATTR(lux, S_IRUGO, isl29003_show_lux, NULL); + +static struct attribute *isl29003_attributes[] = { + &dev_attr_range.attr, + &dev_attr_resolution.attr, + &dev_attr_mode.attr, + &dev_attr_power_state.attr, + &dev_attr_lux.attr, + NULL +}; + +static const struct attribute_group isl29003_attr_group = { + .attrs = isl29003_attributes, +}; + +static int isl29003_init_client(struct i2c_client *client) +{ + struct isl29003_data *data = i2c_get_clientdata(client); + int i; + + /* read all the registers once to fill the cache. + * if one of the reads fails, we consider the init failed */ + for (i = 0; i < ARRAY_SIZE(data->reg_cache); i++) { + int v = i2c_smbus_read_byte_data(client, i); + if (v < 0) + return -ENODEV; + + data->reg_cache[i] = v; + } + + /* set defaults */ + isl29003_set_range(client, 0); + isl29003_set_resolution(client, 0); + isl29003_set_mode(client, 0); + isl29003_set_power_state(client, 0); + + return 0; +} + +/* + * I2C layer + */ + +static int __devinit isl29003_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent); + struct isl29003_data *data; + int err = 0; + + if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE)) + return -EIO; + + data = kzalloc(sizeof(struct isl29003_data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->client = client; + i2c_set_clientdata(client, data); + mutex_init(&data->lock); + + /* initialize the ISL29003 chip */ + err = isl29003_init_client(client); + if (err) + goto exit_kfree; + + /* register sysfs hooks */ + err = sysfs_create_group(&client->dev.kobj, &isl29003_attr_group); + if (err) + goto exit_kfree; + + dev_info(&client->dev, "driver version %s enabled\n", DRIVER_VERSION); + return 0; + +exit_kfree: + kfree(data); + return err; +} + +static int __devexit isl29003_remove(struct i2c_client *client) +{ + sysfs_remove_group(&client->dev.kobj, &isl29003_attr_group); + isl29003_set_power_state(client, 0); + kfree(i2c_get_clientdata(client)); + return 0; +} + +#ifdef CONFIG_PM +static int isl29003_suspend(struct i2c_client *client, pm_message_t mesg) +{ + return isl29003_set_power_state(client, 0); +} + +static int isl29003_resume(struct i2c_client *client) +{ + int i; + struct isl29003_data *data = i2c_get_clientdata(client); + + /* restore registers from cache */ + for (i = 0; i < ARRAY_SIZE(data->reg_cache); i++) + if (!i2c_smbus_write_byte_data(client, i, data->reg_cache[i])) + return -EIO; + + return 0; +} + +#else +#define isl29003_suspend NULL +#define isl29003_resume NULL +#endif /* CONFIG_PM */ + +static const struct i2c_device_id isl29003_id[] = { + { "isl29003", 0 }, + {} +}; +MODULE_DEVICE_TABLE(i2c, isl29003_id); + +static struct i2c_driver isl29003_driver = { + .driver = { + .name = ISL29003_DRV_NAME, + .owner = THIS_MODULE, + }, + .suspend = isl29003_suspend, + .resume = isl29003_resume, + .probe = isl29003_probe, + .remove = __devexit_p(isl29003_remove), + .id_table = isl29003_id, +}; + +static int __init isl29003_init(void) +{ + return i2c_add_driver(&isl29003_driver); +} + +static void __exit isl29003_exit(void) +{ + i2c_del_driver(&isl29003_driver); +} + +MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>"); +MODULE_DESCRIPTION("ISL29003 ambient light sensor driver"); +MODULE_LICENSE("GPL v2"); +MODULE_VERSION(DRIVER_VERSION); + +module_init(isl29003_init); +module_exit(isl29003_exit); + |