diff options
Diffstat (limited to 'drivers/misc/hmc6352.c')
| -rw-r--r-- | drivers/misc/hmc6352.c | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/drivers/misc/hmc6352.c b/drivers/misc/hmc6352.c new file mode 100644 index 000000000000..234bfcaf2099 --- /dev/null +++ b/drivers/misc/hmc6352.c | |||
| @@ -0,0 +1,166 @@ | |||
| 1 | /* | ||
| 2 | * hmc6352.c - Honeywell Compass Driver | ||
| 3 | * | ||
| 4 | * Copyright (C) 2009 Intel Corp | ||
| 5 | * | ||
| 6 | * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ | ||
| 7 | * | ||
| 8 | * This program is free software; you can redistribute it and/or modify | ||
| 9 | * it under the terms of the GNU General Public License as published by | ||
| 10 | * the Free Software Foundation; version 2 of the License. | ||
| 11 | * | ||
| 12 | * This program is distributed in the hope that it will be useful, but | ||
| 13 | * WITHOUT ANY WARRANTY; without even the implied warranty of | ||
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | ||
| 15 | * General Public License for more details. | ||
| 16 | * | ||
| 17 | * You should have received a copy of the GNU General Public License along | ||
| 18 | * with this program; if not, write to the Free Software Foundation, Inc., | ||
| 19 | * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. | ||
| 20 | * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ | ||
| 21 | * | ||
| 22 | */ | ||
| 23 | |||
| 24 | #include <linux/module.h> | ||
| 25 | #include <linux/init.h> | ||
| 26 | #include <linux/slab.h> | ||
| 27 | #include <linux/i2c.h> | ||
| 28 | #include <linux/err.h> | ||
| 29 | #include <linux/delay.h> | ||
| 30 | #include <linux/sysfs.h> | ||
| 31 | |||
| 32 | static DEFINE_MUTEX(compass_mutex); | ||
| 33 | |||
| 34 | static int compass_command(struct i2c_client *c, u8 cmd) | ||
| 35 | { | ||
| 36 | int ret = i2c_master_send(c, &cmd, 1); | ||
| 37 | if (ret < 0) | ||
| 38 | dev_warn(&c->dev, "command '%c' failed.\n", cmd); | ||
| 39 | return ret; | ||
| 40 | } | ||
| 41 | |||
| 42 | static int compass_store(struct device *dev, const char *buf, size_t count, | ||
| 43 | const char *map) | ||
| 44 | { | ||
| 45 | struct i2c_client *c = to_i2c_client(dev); | ||
| 46 | int ret; | ||
| 47 | unsigned long val; | ||
| 48 | |||
| 49 | if (strict_strtoul(buf, 10, &val)) | ||
| 50 | return -EINVAL; | ||
| 51 | if (val >= strlen(map)) | ||
| 52 | return -EINVAL; | ||
| 53 | mutex_lock(&compass_mutex); | ||
| 54 | ret = compass_command(c, map[val]); | ||
| 55 | mutex_unlock(&compass_mutex); | ||
| 56 | if (ret < 0) | ||
| 57 | return ret; | ||
| 58 | return count; | ||
| 59 | } | ||
| 60 | |||
| 61 | static ssize_t compass_calibration_store(struct device *dev, | ||
| 62 | struct device_attribute *attr, const char *buf, size_t count) | ||
| 63 | { | ||
| 64 | return compass_store(dev, buf, count, "EC"); | ||
| 65 | } | ||
| 66 | |||
| 67 | static ssize_t compass_power_mode_store(struct device *dev, | ||
| 68 | struct device_attribute *attr, const char *buf, size_t count) | ||
| 69 | { | ||
| 70 | return compass_store(dev, buf, count, "SW"); | ||
| 71 | } | ||
| 72 | |||
| 73 | static ssize_t compass_heading_data_show(struct device *dev, | ||
| 74 | struct device_attribute *attr, char *buf) | ||
| 75 | { | ||
| 76 | struct i2c_client *client = to_i2c_client(dev); | ||
| 77 | unsigned char i2c_data[2]; | ||
| 78 | unsigned int ret; | ||
| 79 | |||
| 80 | mutex_lock(&compass_mutex); | ||
| 81 | ret = compass_command(client, 'A'); | ||
| 82 | if (ret != 1) { | ||
| 83 | mutex_unlock(&compass_mutex); | ||
| 84 | return ret; | ||
| 85 | } | ||
| 86 | msleep(10); /* sending 'A' cmd we need to wait for 7-10 millisecs */ | ||
| 87 | ret = i2c_master_recv(client, i2c_data, 2); | ||
| 88 | mutex_unlock(&compass_mutex); | ||
| 89 | if (ret != 1) { | ||
| 90 | dev_warn(dev, "i2c read data cmd failed\n"); | ||
| 91 | return ret; | ||
| 92 | } | ||
| 93 | ret = (i2c_data[0] << 8) | i2c_data[1]; | ||
| 94 | return sprintf(buf, "%d.%d\n", ret/10, ret%10); | ||
| 95 | } | ||
| 96 | |||
| 97 | |||
| 98 | static DEVICE_ATTR(heading0_input, S_IRUGO, compass_heading_data_show, NULL); | ||
| 99 | static DEVICE_ATTR(calibration, S_IWUSR, NULL, compass_calibration_store); | ||
| 100 | static DEVICE_ATTR(power_state, S_IWUSR, NULL, compass_power_mode_store); | ||
| 101 | |||
| 102 | static struct attribute *mid_att_compass[] = { | ||
| 103 | &dev_attr_heading0_input.attr, | ||
| 104 | &dev_attr_calibration.attr, | ||
| 105 | &dev_attr_power_state.attr, | ||
| 106 | NULL | ||
| 107 | }; | ||
| 108 | |||
| 109 | static const struct attribute_group m_compass_gr = { | ||
| 110 | .name = "hmc6352", | ||
| 111 | .attrs = mid_att_compass | ||
| 112 | }; | ||
| 113 | |||
| 114 | static int hmc6352_probe(struct i2c_client *client, | ||
| 115 | const struct i2c_device_id *id) | ||
| 116 | { | ||
| 117 | int res; | ||
| 118 | |||
| 119 | res = sysfs_create_group(&client->dev.kobj, &m_compass_gr); | ||
| 120 | if (res) { | ||
| 121 | dev_err(&client->dev, "device_create_file failed\n"); | ||
| 122 | return res; | ||
| 123 | } | ||
| 124 | dev_info(&client->dev, "%s HMC6352 compass chip found\n", | ||
| 125 | client->name); | ||
| 126 | return 0; | ||
| 127 | } | ||
| 128 | |||
| 129 | static int hmc6352_remove(struct i2c_client *client) | ||
| 130 | { | ||
| 131 | sysfs_remove_group(&client->dev.kobj, &m_compass_gr); | ||
| 132 | return 0; | ||
| 133 | } | ||
| 134 | |||
| 135 | static struct i2c_device_id hmc6352_id[] = { | ||
| 136 | { "hmc6352", 0 }, | ||
| 137 | { } | ||
| 138 | }; | ||
| 139 | |||
| 140 | MODULE_DEVICE_TABLE(i2c, hmc6352_id); | ||
| 141 | |||
| 142 | static struct i2c_driver hmc6352_driver = { | ||
| 143 | .driver = { | ||
| 144 | .name = "hmc6352", | ||
| 145 | }, | ||
| 146 | .probe = hmc6352_probe, | ||
| 147 | .remove = hmc6352_remove, | ||
| 148 | .id_table = hmc6352_id, | ||
| 149 | }; | ||
| 150 | |||
| 151 | static int __init sensor_hmc6352_init(void) | ||
| 152 | { | ||
| 153 | return i2c_add_driver(&hmc6352_driver); | ||
| 154 | } | ||
| 155 | |||
| 156 | static void __exit sensor_hmc6352_exit(void) | ||
| 157 | { | ||
| 158 | i2c_del_driver(&hmc6352_driver); | ||
| 159 | } | ||
| 160 | |||
| 161 | module_init(sensor_hmc6352_init); | ||
| 162 | module_exit(sensor_hmc6352_exit); | ||
| 163 | |||
| 164 | MODULE_AUTHOR("Kalhan Trisal <kalhan.trisal@intel.com"); | ||
| 165 | MODULE_DESCRIPTION("hmc6352 Compass Driver"); | ||
| 166 | MODULE_LICENSE("GPL v2"); | ||
