diff options
Diffstat (limited to 'drivers/misc/mpu3050/compass/lsm303m.c')
| -rwxr-xr-x | drivers/misc/mpu3050/compass/lsm303m.c | 244 |
1 files changed, 244 insertions, 0 deletions
diff --git a/drivers/misc/mpu3050/compass/lsm303m.c b/drivers/misc/mpu3050/compass/lsm303m.c new file mode 100755 index 00000000000..871d002fd36 --- /dev/null +++ b/drivers/misc/mpu3050/compass/lsm303m.c @@ -0,0 +1,244 @@ +/* + $License: + Copyright (C) 2010 InvenSense Corporation, All Rights Reserved. + + 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, see <http://www.gnu.org/licenses/>. + $ + */ + +/** + * @brief Provides the interface to setup and handle a compass + * connected to the primary I2C interface of the gyroscope. + * + * @{ + * @file lsm303m.c + * @brief Magnetometer setup and handling methods for ST LSM303. + */ + +/* ------------------ */ +/* - Include Files. - */ +/* ------------------ */ + +#ifdef __KERNEL__ +#include <linux/module.h> +#endif + +#include "mpu.h" +#include "mlsl.h" +#include "mlos.h" + +#include <log.h> +#undef MPL_LOG_TAG +#define MPL_LOG_TAG "MPL-compass" + +/*----- ST LSM303 Registers ------*/ +enum LSM_REG { + LSM_REG_CONF_A = 0x0, + LSM_REG_CONF_B = 0x1, + LSM_REG_MODE = 0x2, + LSM_REG_X_M = 0x3, + LSM_REG_X_L = 0x4, + LSM_REG_Z_M = 0x5, + LSM_REG_Z_L = 0x6, + LSM_REG_Y_M = 0x7, + LSM_REG_Y_L = 0x8, + LSM_REG_STATUS = 0x9, + LSM_REG_ID_A = 0xA, + LSM_REG_ID_B = 0xB, + LSM_REG_ID_C = 0xC +}; + +enum LSM_CONF_A { + LSM_CONF_A_DRATE_MASK = 0x1C, + LSM_CONF_A_DRATE_0_75 = 0x00, + LSM_CONF_A_DRATE_1_5 = 0x04, + LSM_CONF_A_DRATE_3 = 0x08, + LSM_CONF_A_DRATE_7_5 = 0x0C, + LSM_CONF_A_DRATE_15 = 0x10, + LSM_CONF_A_DRATE_30 = 0x14, + LSM_CONF_A_DRATE_75 = 0x18, + LSM_CONF_A_MEAS_MASK = 0x3, + LSM_CONF_A_MEAS_NORM = 0x0, + LSM_CONF_A_MEAS_POS = 0x1, + LSM_CONF_A_MEAS_NEG = 0x2 +}; + +enum LSM_CONF_B { + LSM_CONF_B_GAIN_MASK = 0xE0, + LSM_CONF_B_GAIN_0_9 = 0x00, + LSM_CONF_B_GAIN_1_2 = 0x20, + LSM_CONF_B_GAIN_1_9 = 0x40, + LSM_CONF_B_GAIN_2_5 = 0x60, + LSM_CONF_B_GAIN_4_0 = 0x80, + LSM_CONF_B_GAIN_4_6 = 0xA0, + LSM_CONF_B_GAIN_5_5 = 0xC0, + LSM_CONF_B_GAIN_7_9 = 0xE0 +}; + +enum LSM_MODE { + LSM_MODE_MASK = 0x3, + LSM_MODE_CONT = 0x0, + LSM_MODE_SINGLE = 0x1, + LSM_MODE_IDLE = 0x2, + LSM_MODE_SLEEP = 0x3 +}; + +/* --------------------- */ +/* - Variables. - */ +/* --------------------- */ + +/***************************************** + Accelerometer Initialization Functions +*****************************************/ + +int lsm303dlhm_suspend(void *mlsl_handle, + struct ext_slave_descr *slave, + struct ext_slave_platform_data *pdata) +{ + int result = ML_SUCCESS; + + result = + MLSLSerialWriteSingle(mlsl_handle, pdata->address, + LSM_REG_MODE, LSM_MODE_SLEEP); + ERROR_CHECK(result); + MLOSSleep(3); + + return result; +} + +int lsm303dlhm_resume(void *mlsl_handle, + struct ext_slave_descr *slave, + struct ext_slave_platform_data *pdata) +{ + int result = ML_SUCCESS; + + /* Use single measurement mode. Start at sleep state. */ + result = + MLSLSerialWriteSingle(mlsl_handle, pdata->address, + LSM_REG_MODE, LSM_MODE_SLEEP); + ERROR_CHECK(result); + /* Config normal measurement */ + result = + MLSLSerialWriteSingle(mlsl_handle, pdata->address, + LSM_REG_CONF_A, 0); + ERROR_CHECK(result); + /* Adjust gain to 320 LSB/Gauss */ + result = + MLSLSerialWriteSingle(mlsl_handle, pdata->address, + LSM_REG_CONF_B, LSM_CONF_B_GAIN_5_5); + ERROR_CHECK(result); + + return result; +} + +int lsm303dlhm_read(void *mlsl_handle, + struct ext_slave_descr *slave, + struct ext_slave_platform_data *pdata, + unsigned char *data) +{ + unsigned char stat; + tMLError result = ML_SUCCESS; + short axisFixed; + + /* Read status reg. to check if data is ready */ + result = + MLSLSerialRead(mlsl_handle, pdata->address, LSM_REG_STATUS, 1, + &stat); + ERROR_CHECK(result); + if (stat & 0x01) { + result = + MLSLSerialRead(mlsl_handle, pdata->address, + LSM_REG_X_M, 6, (unsigned char *) data); + ERROR_CHECK(result); + + /*drop data if overflows */ + if ((data[0] == 0xf0) || (data[2] == 0xf0) + || (data[4] == 0xf0)) { + /* trigger next measurement read */ + result = + MLSLSerialWriteSingle(mlsl_handle, + pdata->address, + LSM_REG_MODE, + LSM_MODE_SINGLE); + ERROR_CHECK(result); + return ML_ERROR_COMPASS_DATA_OVERFLOW; + } + /* convert to fixed point and apply sensitivity correction for + Z-axis */ + axisFixed = + (short) ((unsigned short) data[5] + + (unsigned short) data[4] * 256); + /* scale up by 1.125 (36/32) approximate of 1.122 (320/285) */ + axisFixed = (short) (axisFixed * 36); + data[4] = axisFixed >> 8; + data[5] = axisFixed & 0xFF; + + axisFixed = + (short) ((unsigned short) data[3] + + (unsigned short) data[2] * 256); + axisFixed = (short) (axisFixed * 32); + data[2] = axisFixed >> 8; + data[3] = axisFixed & 0xFF; + + axisFixed = + (short) ((unsigned short) data[1] + + (unsigned short) data[0] * 256); + axisFixed = (short) (axisFixed * 32); + data[0] = axisFixed >> 8; + data[1] = axisFixed & 0xFF; + + /* trigger next measurement read */ + result = + MLSLSerialWriteSingle(mlsl_handle, pdata->address, + LSM_REG_MODE, LSM_MODE_SINGLE); + ERROR_CHECK(result); + + return ML_SUCCESS; + } else { + /* trigger next measurement read */ + result = + MLSLSerialWriteSingle(mlsl_handle, pdata->address, + LSM_REG_MODE, LSM_MODE_SINGLE); + ERROR_CHECK(result); + + return ML_ERROR_COMPASS_DATA_NOT_READY; + } +} + +struct ext_slave_descr lsm303dlhm_descr = { + /*.init = */ NULL, + /*.exit = */ NULL, + /*.suspend = */ lsm303dlhm_suspend, + /*.resume = */ lsm303dlhm_resume, + /*.read = */ lsm303dlhm_read, + /*.config = */ NULL, + /*.get_config = */ NULL, + /*.name = */ "lsm303dlhm", + /*.type = */ EXT_SLAVE_TYPE_COMPASS, + /*.id = */ COMPASS_ID_LSM303, + /*.reg = */ 0x06, + /*.len = */ 6, + /*.endian = */ EXT_SLAVE_BIG_ENDIAN, + /*.range = */ {10240, 0}, +}; + +struct ext_slave_descr *lsm303dlhm_get_slave_descr(void) +{ + return &lsm303dlhm_descr; +} +EXPORT_SYMBOL(lsm303dlhm_get_slave_descr); + +/** + * @} +**/ |