From cfa3b24c38b58cb6acabe6441b4668e530e957af Mon Sep 17 00:00:00 2001 From: Kalhan Trisal Date: Mon, 9 Aug 2010 17:21:05 -0700 Subject: [PATCH] hmc6352: add driver for the HMC6352 compass This driver will report the heading values in degrees to the sysfs interface. The values returned are headings . e.g. 245.6 Alan: Cleanups requested now all folded in and a sysfs description to keep Andrew happy. The sysfs description now resembles hwmon. Signed-off-by: Kalhan Trisal Reviewed-by: Jean Delvare Signed-off-by: Alan Cox Cc: Jonathan Cameron Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- .../ABI/testing/sysfs-bus-i2c-devices-hm6352 | 21 +++ drivers/misc/Kconfig | 7 + drivers/misc/Makefile | 1 + drivers/misc/hmc6352.c | 166 ++++++++++++++++++ 4 files changed, 195 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-bus-i2c-devices-hm6352 create mode 100644 drivers/misc/hmc6352.c diff --git a/Documentation/ABI/testing/sysfs-bus-i2c-devices-hm6352 b/Documentation/ABI/testing/sysfs-bus-i2c-devices-hm6352 new file mode 100644 index 00000000000..feb2e4a8707 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-bus-i2c-devices-hm6352 @@ -0,0 +1,21 @@ +Where: /sys/bus/i2c/devices/.../heading0_input +Date: April 2010 +Kernel Version: 2.6.36? +Contact: alan.cox@intel.com +Description: Reports the current heading from the compass as a floating + point value in degrees. + +Where: /sys/bus/i2c/devices/.../power_state +Date: April 2010 +Kernel Version: 2.6.36? +Contact: alan.cox@intel.com +Description: Sets the power state of the device. 0 sets the device into + sleep mode, 1 wakes it up. + +Where: /sys/bus/i2c/devices/.../calibration +Date: April 2010 +Kernel Version: 2.6.36? +Contact: alan.cox@intel.com +Description: Sets the calibration on or off (1 = on, 0 = off). See the + chip data sheet. + diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig index 3b4b7562b2f..0b591b65824 100644 --- a/drivers/misc/Kconfig +++ b/drivers/misc/Kconfig @@ -314,6 +314,13 @@ config SENSORS_BH1780 This driver can also be built as a module. If so, the module will be called bh1780gli. +config HMC6352 + tristate "Honeywell HMC6352 compass" + depends on I2C + help + This driver provides support for the Honeywell HMC6352 compass, + providing configuration and heading data via sysfs. + config EP93XX_PWM tristate "EP93xx PWM support" depends on ARCH_EP93XX diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile index c0621fbacb2..255a80dc9d7 100644 --- a/drivers/misc/Makefile +++ b/drivers/misc/Makefile @@ -30,6 +30,7 @@ obj-$(CONFIG_DS1682) += ds1682.o obj-$(CONFIG_TI_DAC7512) += ti_dac7512.o obj-$(CONFIG_C2PORT) += c2port/ obj-$(CONFIG_IWMC3200TOP) += iwmc3200top/ +obj-$(CONFIG_HMC6352) += hmc6352.o obj-y += eeprom/ obj-y += cb710/ obj-$(CONFIG_VMWARE_BALLOON) += vmware_balloon.o diff --git a/drivers/misc/hmc6352.c b/drivers/misc/hmc6352.c new file mode 100644 index 00000000000..234bfcaf209 --- /dev/null +++ b/drivers/misc/hmc6352.c @@ -0,0 +1,166 @@ +/* + * hmc6352.c - Honeywell Compass Driver + * + * Copyright (C) 2009 Intel Corp + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * 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; version 2 of the License. + * + * 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., + * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + */ + +#include +#include +#include +#include +#include +#include +#include + +static DEFINE_MUTEX(compass_mutex); + +static int compass_command(struct i2c_client *c, u8 cmd) +{ + int ret = i2c_master_send(c, &cmd, 1); + if (ret < 0) + dev_warn(&c->dev, "command '%c' failed.\n", cmd); + return ret; +} + +static int compass_store(struct device *dev, const char *buf, size_t count, + const char *map) +{ + struct i2c_client *c = to_i2c_client(dev); + int ret; + unsigned long val; + + if (strict_strtoul(buf, 10, &val)) + return -EINVAL; + if (val >= strlen(map)) + return -EINVAL; + mutex_lock(&compass_mutex); + ret = compass_command(c, map[val]); + mutex_unlock(&compass_mutex); + if (ret < 0) + return ret; + return count; +} + +static ssize_t compass_calibration_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t count) +{ + return compass_store(dev, buf, count, "EC"); +} + +static ssize_t compass_power_mode_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t count) +{ + return compass_store(dev, buf, count, "SW"); +} + +static ssize_t compass_heading_data_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct i2c_client *client = to_i2c_client(dev); + unsigned char i2c_data[2]; + unsigned int ret; + + mutex_lock(&compass_mutex); + ret = compass_command(client, 'A'); + if (ret != 1) { + mutex_unlock(&compass_mutex); + return ret; + } + msleep(10); /* sending 'A' cmd we need to wait for 7-10 millisecs */ + ret = i2c_master_recv(client, i2c_data, 2); + mutex_unlock(&compass_mutex); + if (ret != 1) { + dev_warn(dev, "i2c read data cmd failed\n"); + return ret; + } + ret = (i2c_data[0] << 8) | i2c_data[1]; + return sprintf(buf, "%d.%d\n", ret/10, ret%10); +} + + +static DEVICE_ATTR(heading0_input, S_IRUGO, compass_heading_data_show, NULL); +static DEVICE_ATTR(calibration, S_IWUSR, NULL, compass_calibration_store); +static DEVICE_ATTR(power_state, S_IWUSR, NULL, compass_power_mode_store); + +static struct attribute *mid_att_compass[] = { + &dev_attr_heading0_input.attr, + &dev_attr_calibration.attr, + &dev_attr_power_state.attr, + NULL +}; + +static const struct attribute_group m_compass_gr = { + .name = "hmc6352", + .attrs = mid_att_compass +}; + +static int hmc6352_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + int res; + + res = sysfs_create_group(&client->dev.kobj, &m_compass_gr); + if (res) { + dev_err(&client->dev, "device_create_file failed\n"); + return res; + } + dev_info(&client->dev, "%s HMC6352 compass chip found\n", + client->name); + return 0; +} + +static int hmc6352_remove(struct i2c_client *client) +{ + sysfs_remove_group(&client->dev.kobj, &m_compass_gr); + return 0; +} + +static struct i2c_device_id hmc6352_id[] = { + { "hmc6352", 0 }, + { } +}; + +MODULE_DEVICE_TABLE(i2c, hmc6352_id); + +static struct i2c_driver hmc6352_driver = { + .driver = { + .name = "hmc6352", + }, + .probe = hmc6352_probe, + .remove = hmc6352_remove, + .id_table = hmc6352_id, +}; + +static int __init sensor_hmc6352_init(void) +{ + return i2c_add_driver(&hmc6352_driver); +} + +static void __exit sensor_hmc6352_exit(void) +{ + i2c_del_driver(&hmc6352_driver); +} + +module_init(sensor_hmc6352_init); +module_exit(sensor_hmc6352_exit); + +MODULE_AUTHOR("Kalhan Trisal