From 7efe15f2a4cd9d40826d31d7d5ef56094f8b65f5 Mon Sep 17 00:00:00 2001 From: Hemanth V Date: Mon, 9 Aug 2010 17:20:25 -0700 Subject: [PATCH] drivers/misc: ROHM BH1780GLI ambient light sensor driver Add support for ROHM BH1780GLI Ambient light sensor. BH1780 supports I2C interface. Driver supports read/update of power state and read of lux value (through SYSFS). Writing value 3 to power_state enables the sensor and current lux value could be read. Currently this driver follows the same sysfs convention as supported by drivers/misc/isl29003.c. Signed-off-by: Hemanth V Reviewed-by: Daniel Mack Acked-by: Jonathan Cameron Cc: Jean Delvare Cc: Wolfram Sang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/misc/Kconfig | 10 ++ drivers/misc/Makefile | 1 + drivers/misc/bh1780gli.c | 273 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 284 insertions(+) create mode 100644 drivers/misc/bh1780gli.c diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig index 488f25472291..2483183419b9 100644 --- a/drivers/misc/Kconfig +++ b/drivers/misc/Kconfig @@ -304,6 +304,16 @@ config SENSORS_TSL2550 This driver can also be built as a module. If so, the module will be called tsl2550. +config SENSORS_BH1780 + tristate "ROHM BH1780GLI ambient light sensor" + depends on I2C && SYSFS + help + If you say yes here you get support for the ROHM BH1780GLI + ambient light sensor. + + This driver can also be built as a module. If so, the module + will be called bh1780gli. + config EP93XX_PWM tristate "EP93xx PWM support" depends on ARCH_EP93XX diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile index 67552d6e9327..21ae73c38005 100644 --- a/drivers/misc/Makefile +++ b/drivers/misc/Makefile @@ -14,6 +14,7 @@ obj-$(CONFIG_LKDTM) += lkdtm.o obj-$(CONFIG_TIFM_CORE) += tifm_core.o obj-$(CONFIG_TIFM_7XX1) += tifm_7xx1.o obj-$(CONFIG_PHANTOM) += phantom.o +obj-$(CONFIG_SENSORS_BH1780) += bh1780gli.o obj-$(CONFIG_SGI_IOC4) += ioc4.o obj-$(CONFIG_ENCLOSURE_SERVICES) += enclosure.o obj-$(CONFIG_KGDB_TESTS) += kgdbts.o diff --git a/drivers/misc/bh1780gli.c b/drivers/misc/bh1780gli.c new file mode 100644 index 000000000000..714c6b487313 --- /dev/null +++ b/drivers/misc/bh1780gli.c @@ -0,0 +1,273 @@ +/* + * bh1780gli.c + * ROHM Ambient Light Sensor Driver + * + * Copyright (C) 2010 Texas Instruments + * Author: Hemanth V + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * 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, see . + */ +#include +#include +#include +#include +#include + +#define BH1780_REG_CONTROL 0x80 +#define BH1780_REG_PARTID 0x8A +#define BH1780_REG_MANFID 0x8B +#define BH1780_REG_DLOW 0x8C +#define BH1780_REG_DHIGH 0x8D + +#define BH1780_REVMASK (0xf) +#define BH1780_POWMASK (0x3) +#define BH1780_POFF (0x0) +#define BH1780_PON (0x3) + +/* power on settling time in ms */ +#define BH1780_PON_DELAY 2 + +struct bh1780_data { + struct i2c_client *client; + int power_state; + /* lock for sysfs operations */ + struct mutex lock; +}; + +static int bh1780_write(struct bh1780_data *ddata, u8 reg, u8 val, char *msg) +{ + int ret = i2c_smbus_write_byte_data(ddata->client, reg, val); + if (ret < 0) + dev_err(&ddata->client->dev, + "i2c_smbus_write_byte_data failed error %d\ + Register (%s)\n", ret, msg); + return ret; +} + +static int bh1780_read(struct bh1780_data *ddata, u8 reg, char *msg) +{ + int ret = i2c_smbus_read_byte_data(ddata->client, reg); + if (ret < 0) + dev_err(&ddata->client->dev, + "i2c_smbus_read_byte_data failed error %d\ + Register (%s)\n", ret, msg); + return ret; +} + +static ssize_t bh1780_show_lux(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct platform_device *pdev = to_platform_device(dev); + struct bh1780_data *ddata = platform_get_drvdata(pdev); + int lsb, msb; + + lsb = bh1780_read(ddata, BH1780_REG_DLOW, "DLOW"); + if (lsb < 0) + return lsb; + + msb = bh1780_read(ddata, BH1780_REG_DHIGH, "DHIGH"); + if (msb < 0) + return msb; + + return sprintf(buf, "%d\n", (msb << 8) | lsb); +} + +static ssize_t bh1780_show_power_state(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct platform_device *pdev = to_platform_device(dev); + struct bh1780_data *ddata = platform_get_drvdata(pdev); + int state; + + state = bh1780_read(ddata, BH1780_REG_CONTROL, "CONTROL"); + if (state < 0) + return state; + + return sprintf(buf, "%d\n", state & BH1780_POWMASK); +} + +static ssize_t bh1780_store_power_state(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct platform_device *pdev = to_platform_device(dev); + struct bh1780_data *ddata = platform_get_drvdata(pdev); + unsigned long val; + int error; + + error = strict_strtoul(buf, 0, &val); + if (error) + return error; + + if (val < BH1780_POFF || val > BH1780_PON) + return -EINVAL; + + mutex_lock(&ddata->lock); + + error = bh1780_write(ddata, BH1780_REG_CONTROL, val, "CONTROL"); + if (error < 0) { + mutex_unlock(&ddata->lock); + return error; + } + + msleep(BH1780_PON_DELAY); + ddata->power_state = val; + mutex_unlock(&ddata->lock); + + return count; +} + +static DEVICE_ATTR(lux, S_IRUGO, bh1780_show_lux, NULL); + +static DEVICE_ATTR(power_state, S_IWUSR | S_IRUGO, + bh1780_show_power_state, bh1780_store_power_state); + +static struct attribute *bh1780_attributes[] = { + &dev_attr_power_state.attr, + &dev_attr_lux.attr, + NULL +}; + +static const struct attribute_group bh1780_attr_group = { + .attrs = bh1780_attributes, +}; + +static int __devinit bh1780_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + int ret; + struct bh1780_data *ddata = NULL; + struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent); + + if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE)) { + ret = -EIO; + goto err_op_failed; + } + + ddata = kzalloc(sizeof(struct bh1780_data), GFP_KERNEL); + if (ddata == NULL) { + ret = -ENOMEM; + goto err_op_failed; + } + + ddata->client = client; + i2c_set_clientdata(client, ddata); + + ret = bh1780_read(ddata, BH1780_REG_PARTID, "PART ID"); + if (ret < 0) + goto err_op_failed; + + dev_info(&client->dev, "Ambient Light Sensor, Rev : %d\n", + (ret & BH1780_REVMASK)); + + mutex_init(&ddata->lock); + + ret = sysfs_create_group(&client->dev.kobj, &bh1780_attr_group); + if (ret) + goto err_op_failed; + + return 0; + +err_op_failed: + kfree(ddata); + return ret; +} + +static int __devexit bh1780_remove(struct i2c_client *client) +{ + struct bh1780_data *ddata; + + ddata = i2c_get_clientdata(client); + sysfs_remove_group(&client->dev.kobj, &bh1780_attr_group); + i2c_set_clientdata(client, NULL); + kfree(ddata); + + return 0; +} + +#ifdef CONFIG_PM +static int bh1780_suspend(struct i2c_client *client, pm_message_t mesg) +{ + struct bh1780_data *ddata; + int state, ret; + + ddata = i2c_get_clientdata(client); + state = bh1780_read(ddata, BH1780_REG_CONTROL, "CONTROL"); + if (state < 0) + return state; + + ddata->power_state = state & BH1780_POWMASK; + + ret = bh1780_write(ddata, BH1780_REG_CONTROL, BH1780_POFF, + "CONTROL"); + + if (ret < 0) + return ret; + + return 0; +} + +static int bh1780_resume(struct i2c_client *client) +{ + struct bh1780_data *ddata; + int state, ret; + + ddata = i2c_get_clientdata(client); + state = ddata->power_state; + + ret = bh1780_write(ddata, BH1780_REG_CONTROL, state, + "CONTROL"); + + if (ret < 0) + return ret; + + return 0; +} +#else +#define bh1780_suspend NULL +#define bh1780_resume NULL +#endif /* CONFIG_PM */ + +static const struct i2c_device_id bh1780_id[] = { + { "bh1780", 0 }, + { }, +}; + +static struct i2c_driver bh1780_driver = { + .probe = bh1780_probe, + .remove = bh1780_remove, + .id_table = bh1780_id, + .suspend = bh1780_suspend, + .resume = bh1780_resume, + .driver = { + .name = "bh1780" + }, +}; + +static int __init bh1780_init(void) +{ + return i2c_add_driver(&bh1780_driver); +} + +static void __exit bh1780_exit(void) +{ + i2c_del_driver(&bh1780_driver); +} + +module_init(bh1780_init) +module_exit(bh1780_exit) + +MODULE_DESCRIPTION("BH1780GLI Ambient Light Sensor Driver"); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Hemanth V "); -- 2.20.1