Re: [PATCH 11/11] misc: Add slave driver for bma085 pressure sensor
From: Jonathan Cameron
Date: Fri Jul 01 2011 - 04:57:18 EST
Hang on, so your motion processing unit takes in a pressure sensor?
Interesting....
Manuel, am I imagining things or did you have a driver for one of these?
Happy to take barometers in IIO.
> Signed-off-by: Nathan Royer <nroyer@xxxxxxxxxxxxxx>
> ---
> drivers/misc/inv_mpu/Kconfig | 1 +
> drivers/misc/inv_mpu/Makefile | 1 +
> drivers/misc/inv_mpu/pressure/Kconfig | 20 ++
> drivers/misc/inv_mpu/pressure/Makefile | 8 +
> drivers/misc/inv_mpu/pressure/bma085.c | 367 ++++++++++++++++++++++++++++++++
> 5 files changed, 397 insertions(+), 0 deletions(-)
> create mode 100644 drivers/misc/inv_mpu/pressure/Kconfig
> create mode 100644 drivers/misc/inv_mpu/pressure/Makefile
> create mode 100644 drivers/misc/inv_mpu/pressure/bma085.c
>
> diff --git a/drivers/misc/inv_mpu/Kconfig b/drivers/misc/inv_mpu/Kconfig
> index 7d9f2c3..ea7d754 100644
> --- a/drivers/misc/inv_mpu/Kconfig
> +++ b/drivers/misc/inv_mpu/Kconfig
> @@ -57,5 +57,6 @@ endchoice
>
> source "drivers/misc/inv_mpu/accel/Kconfig"
> source "drivers/misc/inv_mpu/compass/Kconfig"
> +source "drivers/misc/inv_mpu/pressure/Kconfig"
>
> endif #INV_SENSORS
> diff --git a/drivers/misc/inv_mpu/Makefile b/drivers/misc/inv_mpu/Makefile
> index dc77a1b..506b8f5 100644
> --- a/drivers/misc/inv_mpu/Makefile
> +++ b/drivers/misc/inv_mpu/Makefile
> @@ -18,3 +18,4 @@ EXTRA_CFLAGS += -Idrivers/misc/inv_mpu
>
> obj-y += accel/
> obj-y += compass/
> +obj-y += pressure/
> diff --git a/drivers/misc/inv_mpu/pressure/Kconfig b/drivers/misc/inv_mpu/pressure/Kconfig
> new file mode 100644
> index 0000000..f1c021e
> --- /dev/null
> +++ b/drivers/misc/inv_mpu/pressure/Kconfig
> @@ -0,0 +1,20 @@
> +menuconfig: INV_SENSORS_PRESSURE
> + bool "Pressure Sensor Slaves"
> + depends on INV_SENSORS
> + default y
> + help
> + Select y to see a list of supported pressure sensors that can be
> + integrated with the MPUxxxx set of motion processors.
> +
> +if INV_SENSORS_PRESSURE
> +
> +config MPU_SENSORS_BMA085
> + tristate "Bosch BMA085"
> + help
> + This enables support for the Bosch bma085 pressure sensor
> + This support is for integration with the MPU3050 or MPU6050 gyroscope
> + device driver. Only one accelerometer can be registered at a time.
> + Specifying more that one accelerometer in the board file will result
> + in runtime errors.
That's a seriously weird message for a pressure sensor...
> +
> +endif
> diff --git a/drivers/misc/inv_mpu/pressure/Makefile b/drivers/misc/inv_mpu/pressure/Makefile
> new file mode 100644
> index 0000000..595923d
> --- /dev/null
> +++ b/drivers/misc/inv_mpu/pressure/Makefile
> @@ -0,0 +1,8 @@
> +#
> +# Pressure Slaves to MPUxxxx
> +#
> +obj-$(CONFIG_MPU_SENSORS_BMA085) += inv_mpu_bma085.o
> +inv_mpu_bma085-objs += bma085.o
> +
> +EXTRA_CFLAGS += -Idrivers/misc/inv_mpu
> +EXTRA_CFLAGS += -D__C99_DESIGNATED_INITIALIZER
> diff --git a/drivers/misc/inv_mpu/pressure/bma085.c b/drivers/misc/inv_mpu/pressure/bma085.c
> new file mode 100644
> index 0000000..696d2b6
> --- /dev/null
> +++ b/drivers/misc/inv_mpu/pressure/bma085.c
> @@ -0,0 +1,367 @@
> +/*
> + $License:
> + Copyright (C) 2011 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/>.
> + $
> + */
> +
> +/**
> + * @defgroup ACCELDL (Motion Library - Pressure Driver Layer)
> + * @brief Provides the interface to setup and handle a pressure
> + * connected to the secondary I2C interface of the gyroscope.
> + *
> + * @{
> + * @file bma085.c
> + * @brief Pressure setup and handling methods.
> + */
> +
> +/* ------------------ */
> +/* - Include Files. - */
> +/* ------------------ */
> +
> +#include <linux/i2c.h>
> +#include <linux/module.h>
> +#include <linux/moduleparam.h>
> +#include <linux/kernel.h>
> +#include <linux/errno.h>
> +#include <linux/slab.h>
> +#include <linux/delay.h>
> +#include "mpu-dev.h"
> +
> +#include <linux/mpu.h>
> +#include "mlsl.h"
> +#include "log.h"
> +
> +/*
> + * this structure holds all device specific calibration parameters
> + */
> +struct bmp085_calibration_param_t {
> + short ac1;
> + short ac2;
> + short ac3;
> + unsigned short ac4;
> + unsigned short ac5;
> + unsigned short ac6;
> + short b1;
> + short b2;
> + short mb;
> + short mc;
> + short md;
> + long param_b5;
> +};
> +
> +struct bmp085_calibration_param_t cal_param;
> +
> +#define PRESSURE_BMA085_PARAM_MG 3038 /* calibration parameter */
> +#define PRESSURE_BMA085_PARAM_MH -7357 /* calibration parameter */
> +#define PRESSURE_BMA085_PARAM_MI 3791 /* calibration parameter */
> +
> +/*********************************************
> + * Pressure Initialization Functions
> + *********************************************/
> +
> +static int bma085_suspend(void *mlsl_handle,
> + struct ext_slave_descr *slave,
> + struct ext_slave_platform_data *pdata)
> +{
> + int result = INV_SUCCESS;
> + return result;
> +}
> +
> +#define PRESSURE_BMA085_PROM_START_ADDR (0xAA)
> +#define PRESSURE_BMA085_PROM_DATA_LEN (22)
> +#define PRESSURE_BMP085_CTRL_MEAS_REG (0xF4)
> +/* temperature measurent */
> +#define PRESSURE_BMP085_T_MEAS (0x2E)
> +/* pressure measurement; oversampling_setting */
> +#define PRESSURE_BMP085_P_MEAS_OSS_0 (0x34)
> +#define PRESSURE_BMP085_P_MEAS_OSS_1 (0x74)
> +#define PRESSURE_BMP085_P_MEAS_OSS_2 (0xB4)
> +#define PRESSURE_BMP085_P_MEAS_OSS_3 (0xF4)
> +#define PRESSURE_BMP085_ADC_OUT_MSB_REG (0xF6)
> +#define PRESSURE_BMP085_ADC_OUT_LSB_REG (0xF7)
> +
> +static int bma085_resume(void *mlsl_handle,
> + struct ext_slave_descr *slave,
> + struct ext_slave_platform_data *pdata)
> +{
> + int result;
> + unsigned char data[PRESSURE_BMA085_PROM_DATA_LEN];
> +
> + result =
> + inv_serial_read(mlsl_handle, pdata->address,
> + PRESSURE_BMA085_PROM_START_ADDR,
> + PRESSURE_BMA085_PROM_DATA_LEN, data);
> + if (result) {
> + LOG_RESULT_LOCATION(result);
> + return result;
> + }
> +
> + /* parameters AC1-AC6 */
> + cal_param.ac1 = (data[0] << 8) | data[1];
> + cal_param.ac2 = (data[2] << 8) | data[3];
> + cal_param.ac3 = (data[4] << 8) | data[5];
> + cal_param.ac4 = (data[6] << 8) | data[7];
> + cal_param.ac5 = (data[8] << 8) | data[9];
> + cal_param.ac6 = (data[10] << 8) | data[11];
> +
> + /* parameters B1,B2 */
> + cal_param.b1 = (data[12] << 8) | data[13];
> + cal_param.b2 = (data[14] << 8) | data[15];
> +
> + /* parameters MB,MC,MD */
> + cal_param.mb = (data[16] << 8) | data[17];
> + cal_param.mc = (data[18] << 8) | data[19];
> + cal_param.md = (data[20] << 8) | data[21];
> +
> + return result;
> +}
> +
> +static int bma085_read(void *mlsl_handle,
> + struct ext_slave_descr *slave,
> + struct ext_slave_platform_data *pdata,
> + unsigned char *data)
> +{
> + int result;
> + long pressure, x1, x2, x3, b3, b6;
> + unsigned long b4, b7;
> + unsigned long up;
> + unsigned short ut;
> + short oversampling_setting = 0;
> + short temperature;
> + long divisor;
> +
> + /* get temprature */
> + result = inv_serial_single_write(mlsl_handle, pdata->address,
> + PRESSURE_BMP085_CTRL_MEAS_REG,
> + PRESSURE_BMP085_T_MEAS);
> + msleep(5);
> + result =
> + inv_serial_read(mlsl_handle, pdata->address,
> + PRESSURE_BMP085_ADC_OUT_MSB_REG, 2,
> + (unsigned char *)data);
> + if (result) {
> + LOG_RESULT_LOCATION(result);
> + return result;
> + }
> + ut = (data[0] << 8) | data[1];
> +
> + x1 = (((long) ut - (long)cal_param.ac6) * (long)cal_param.ac5) >> 15;
> + divisor = x1 + cal_param.md;
> + if (!divisor)
> + return INV_ERROR_DIVIDE_BY_ZERO;
> +
> + x2 = ((long)cal_param.mc << 11) / (x1 + cal_param.md);
> + cal_param.param_b5 = x1 + x2;
> + /* temperature in 0.1 degree C */
> + temperature = (short)((cal_param.param_b5 + 8) >> 4);
> +
> + /* get pressure */
> + result = inv_serial_single_write(mlsl_handle, pdata->address,
> + PRESSURE_BMP085_CTRL_MEAS_REG,
> + PRESSURE_BMP085_P_MEAS_OSS_0);
> + msleep(5);
> + result =
> + inv_serial_read(mlsl_handle, pdata->address,
> + PRESSURE_BMP085_ADC_OUT_MSB_REG, 2,
> + (unsigned char *)data);
> + if (result) {
> + LOG_RESULT_LOCATION(result);
> + return result;
> + }
> + up = (((unsigned long) data[0] << 8) | ((unsigned long) data[1]));
> +
> + b6 = cal_param.param_b5 - 4000;
> + /* calculate B3 */
> + x1 = (b6*b6) >> 12;
> + x1 *= cal_param.b2;
> + x1 >>= 11;
> +
> + x2 = (cal_param.ac2*b6);
> + x2 >>= 11;
> +
> + x3 = x1 + x2;
> +
> + b3 = (((((long)cal_param.ac1) * 4 + x3)
> + << oversampling_setting) + 2) >> 2;
> +
> + /* calculate B4 */
> + x1 = (cal_param.ac3 * b6) >> 13;
> + x2 = (cal_param.b1 * ((b6*b6) >> 12)) >> 16;
> + x3 = ((x1 + x2) + 2) >> 2;
> + b4 = (cal_param.ac4 * (unsigned long) (x3 + 32768)) >> 15;
> + if (!b4)
> + return INV_ERROR;
> +
> + b7 = ((unsigned long)(up - b3) * (50000>>oversampling_setting));
> + if (b7 < 0x80000000)
> + pressure = (b7 << 1) / b4;
> + else
> + pressure = (b7 / b4) << 1;
> +
> + x1 = pressure >> 8;
> + x1 *= x1;
> + x1 = (x1 * PRESSURE_BMA085_PARAM_MG) >> 16;
> + x2 = (pressure * PRESSURE_BMA085_PARAM_MH) >> 16;
> + /* pressure in Pa */
> + pressure += (x1 + x2 + PRESSURE_BMA085_PARAM_MI) >> 4;
> +
> + data[0] = (unsigned char)(pressure >> 16);
> + data[1] = (unsigned char)(pressure >> 8);
> + data[2] = (unsigned char)(pressure & 0xFF);
> +
> + return result;
> +}
> +
> +static struct ext_slave_descr bma085_descr = {
> + .init = NULL,
> + .exit = NULL,
> + .suspend = bma085_suspend,
> + .resume = bma085_resume,
> + .read = bma085_read,
> + .config = NULL,
> + .get_config = NULL,
> + .name = "bma085",
> + .type = EXT_SLAVE_TYPE_PRESSURE,
> + .id = PRESSURE_ID_BMA085,
> + .read_reg = 0xF6,
> + .read_len = 3,
> + .endian = EXT_SLAVE_BIG_ENDIAN,
> + .range = {0, 0},
> +};
> +
> +static
> +struct ext_slave_descr *bma085_get_slave_descr(void)
> +{
> + return &bma085_descr;
> +}
> +
> +/* Platform data for the MPU */
> +struct bma085_mod_private_data {
> + struct i2c_client *client;
> + struct ext_slave_platform_data *pdata;
> +};
> +
> +static unsigned short normal_i2c[] = { I2C_CLIENT_END };
> +
> +static int bma085_mod_probe(struct i2c_client *client,
> + const struct i2c_device_id *devid)
> +{
> + struct ext_slave_platform_data *pdata;
> + struct bma085_mod_private_data *private_data;
> + int result = 0;
> +
> + dev_info(&client->adapter->dev, "%s: %s\n", __func__, devid->name);
> +
> + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
> + result = -ENODEV;
> + goto out_no_free;
> + }
> +
> + pdata = client->dev.platform_data;
> + if (!pdata) {
> + dev_err(&client->adapter->dev,
> + "Missing platform data for slave %s\n", devid->name);
> + result = -EFAULT;
> + goto out_no_free;
> + }
> +
> + private_data = kzalloc(sizeof(*private_data), GFP_KERNEL);
> + if (!private_data) {
> + result = -ENOMEM;
> + goto out_no_free;
> + }
> +
> + i2c_set_clientdata(client, private_data);
> + private_data->client = client;
> + private_data->pdata = pdata;
> +
> + result = inv_mpu_register_slave(THIS_MODULE, client, pdata,
> + bma085_get_slave_descr);
> + if (result) {
> + dev_err(&client->adapter->dev,
> + "Slave registration failed: %s, %d\n",
> + devid->name, result);
> + goto out_free_memory;
> + }
> +
> + return result;
> +
> +out_free_memory:
> + kfree(private_data);
> +out_no_free:
> + dev_err(&client->adapter->dev, "%s failed %d\n", __func__, result);
> + return result;
> +
> +}
> +
> +static int bma085_mod_remove(struct i2c_client *client)
> +{
> + struct bma085_mod_private_data *private_data =
> + i2c_get_clientdata(client);
> +
> + dev_dbg(&client->adapter->dev, "%s\n", __func__);
> +
> + inv_mpu_unregister_slave(client, private_data->pdata,
> + bma085_get_slave_descr);
> +
> + kfree(private_data);
> + return 0;
> +}
> +
> +static const struct i2c_device_id bma085_mod_id[] = {
> + { "bma085", PRESSURE_ID_BMA085 },
> + {}
> +};
> +
> +MODULE_DEVICE_TABLE(i2c, bma085_mod_id);
> +
> +static struct i2c_driver bma085_mod_driver = {
> + .class = I2C_CLASS_HWMON,
> + .probe = bma085_mod_probe,
> + .remove = bma085_mod_remove,
> + .id_table = bma085_mod_id,
> + .driver = {
> + .owner = THIS_MODULE,
> + .name = "bma085_mod",
> + },
> + .address_list = normal_i2c,
> +};
> +
> +static int __init bma085_mod_init(void)
> +{
> + int res = i2c_add_driver(&bma085_mod_driver);
> + pr_info("%s: Probe name %s\n", __func__, "bma085_mod");
> + if (res)
> + pr_err("%s failed\n", __func__);
> + return res;
> +}
> +
> +static void __exit bma085_mod_exit(void)
> +{
> + pr_info("%s\n", __func__);
> + i2c_del_driver(&bma085_mod_driver);
> +}
> +
> +module_init(bma085_mod_init);
> +module_exit(bma085_mod_exit);
> +
> +MODULE_AUTHOR("Invensense Corporation");
> +MODULE_DESCRIPTION("Driver to integrate BMA085 sensor with the MPU");
> +MODULE_LICENSE("GPL");
> +MODULE_ALIAS("bma085_mod");
> +/**
> + * @}
> +**/
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