/* $NetBSD: bmx280.c,v 1.6 2022/12/01 02:29:37 brad Exp $ */
/*
* Copyright (c) 2022 Brad Spencer <brad@anduin.eldar.org>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: bmx280.c,v 1.6 2022/12/01 02:29:37 brad Exp $");
/*
Driver for the Bosch BMP280/BME280 temperature, humidity (sometimes) and
(usually barometric) pressure sensor
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/device.h>
#include <sys/module.h>
#include <sys/sysctl.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <dev/sysmon/sysmonvar.h>
#include <dev/i2c/i2cvar.h>
#include <dev/i2c/bmx280reg.h>
#include <dev/i2c/bmx280var.h>
static int bmx280_write_register(i2c_tag_t, i2c_addr_t,
uint8_t *, size_t);
static int bmx280_read_register(i2c_tag_t, i2c_addr_t, uint8_t *,
uint8_t *, size_t);
static void bmx280_store_raw_blob_tp(struct bmx280_sc *, uint8_t *);
static void bmx280_store_raw_blob_h(struct bmx280_sc *, uint8_t *);
static int bmx280_poke(i2c_tag_t, i2c_addr_t, bool);
static int bmx280_match(device_t, cfdata_t, void *);
static void bmx280_attach(device_t, device_t, void *);
static int bmx280_detach(device_t, int);
static void bmx280_refresh(struct sysmon_envsys *, envsys_data_t *);
static int bmx280_verify_sysctl(SYSCTLFN_ARGS);
static int bmx280_verify_sysctl_osrs(SYSCTLFN_ARGS);
static int bmx280_verify_sysctl_irr(SYSCTLFN_ARGS);
#define BMX280_DEBUG
#ifdef BMX280_DEBUG
#define DPRINTF(s, l, x) \
do { \
if (l <= s->sc_bmx280debug) \
printf x; \
} while (/*CONSTCOND*/0)
#else
#define DPRINTF(s, l, x)
#endif
CFATTACH_DECL_NEW(bmx280thp, sizeof(struct bmx280_sc),
bmx280_match, bmx280_attach, bmx280_detach, NULL);
static struct bmx280_sensor bmx280_sensors[] = {
{
.desc = "temperature",
.type = ENVSYS_STEMP,
},
{
.desc = "pressure",
.type = ENVSYS_PRESSURE,
},
{
.desc = "humidity",
.type = ENVSYS_SRELHUMIDITY,
}
};
static struct bmx280_osrs_list bmx280_osrs[] = {
{
.text = 1,
.mask = BMX280_OSRS_TP_VALUE_X1,
},
{
.text = 2,
.mask = BMX280_OSRS_TP_VALUE_X2,
},
{
.text = 4,
.mask = BMX280_OSRS_TP_VALUE_X4,
},
{
.text = 8,
.mask = BMX280_OSRS_TP_VALUE_X8,
},
{
.text = 16,
.mask = BMX280_OSRS_TP_VALUE_X16,
}
};
static struct bmx280_irr_list bmx280_irr[] = {
{
.text = 1,
.mask = BMX280_FILTER_VALUE_OFF,
},
{
.text = 2,
.mask = BMX280_FILTER_VALUE_2,
},
{
.text = 5,
.mask = BMX280_FILTER_VALUE_5,
},
{
.text = 11,
.mask = BMX280_FILTER_VALUE_11,
},
{
.text = 22,
.mask = BMX280_FILTER_VALUE_22,
}
};
static uint8_t
bmx280_osrs_text_to_mask(int t)
{
int i;
uint8_t m = 0;
for (i = 0; i < __arraycount(bmx280_osrs); i++) {
if (t == bmx280_osrs[i].text) {
m = bmx280_osrs[i].mask;
break;
}
}
return m;
}
static uint8_t
bmx280_irr_text_to_mask(int t)
{
int i;
uint8_t m = 0;
for (i = 0; i < __arraycount(bmx280_irr); i++) {
if (t == bmx280_irr[i].text) {
m = bmx280_irr[i].mask;
break;
}
}
return m;
}
int
bmx280_verify_sysctl(SYSCTLFN_ARGS)
{
int error, t;
struct sysctlnode node;
node = *rnode;
t = *(int *)rnode->sysctl_data;
node.sysctl_data = &t;
error = sysctl_lookup(SYSCTLFN_CALL(&node));
if (error || newp == NULL)
return error;
if (t < 0)
return EINVAL;
*(int *)rnode->sysctl_data = t;
return 0;
}
int
bmx280_verify_sysctl_osrs(SYSCTLFN_ARGS)
{
struct sysctlnode node;
int error = 0, t;
size_t i;
node = *rnode;
t = *(int *)rnode->sysctl_data;
node.sysctl_data = &t;
error = sysctl_lookup(SYSCTLFN_CALL(&node));
if (error || newp == NULL)
return error;
for (i = 0; i < __arraycount(bmx280_osrs); i++) {
if (t == bmx280_osrs[i].text) {
break;
}
}
if (i == __arraycount(bmx280_osrs))
return EINVAL;
*(int *)rnode->sysctl_data = t;
return error;
}
int
bmx280_verify_sysctl_irr(SYSCTLFN_ARGS)
{
struct sysctlnode node;
int error = 0, t;
size_t i;
node = *rnode;
t = *(int *)rnode->sysctl_data;
node.sysctl_data = &t;
error = sysctl_lookup(SYSCTLFN_CALL(&node));
if (error || newp == NULL)
return error;
for (i = 0; i < __arraycount(bmx280_irr); i++) {
if (t == bmx280_irr[i].text) {
break;
}
}
if (i == __arraycount(bmx280_irr))
return EINVAL;
*(int *)rnode->sysctl_data = t;
return error;
}
/* The datasheet was pretty vague as to the byte order...
* in fact, down right deceptive...
*/
static void
bmx280_store_raw_blob_tp(struct bmx280_sc *sc, uint8_t *b) {
sc->sc_cal_blob.dig_T1 = (uint16_t)b[1] << 8;
sc->sc_cal_blob.dig_T1 = sc->sc_cal_blob.dig_T1 | (uint16_t)b[0];
sc->sc_cal_blob.dig_T2 = (int16_t)b[3] << 8;
sc->sc_cal_blob.dig_T2 = sc->sc_cal_blob.dig_T2 | (int16_t)b[2];
sc->sc_cal_blob.dig_T3 = (int16_t)b[5] << 8;
sc->sc_cal_blob.dig_T3 = sc->sc_cal_blob.dig_T3 | (int16_t)b[4];
sc->sc_cal_blob.dig_P1 = (uint16_t)b[7] << 8;
sc->sc_cal_blob.dig_P1 = sc->sc_cal_blob.dig_P1 | (uint16_t)b[6];
sc->sc_cal_blob.dig_P2 = (int16_t)b[9] << 8;
sc->sc_cal_blob.dig_P2 = sc->sc_cal_blob.dig_P2 | (int16_t)b[8];
sc->sc_cal_blob.dig_P3 = (int16_t)b[11] << 8;
sc->sc_cal_blob.dig_P3 = sc->sc_cal_blob.dig_P3 | (int16_t)b[10];
sc->sc_cal_blob.dig_P4 = (int16_t)b[13] << 8;
sc->sc_cal_blob.dig_P4 = sc->sc_cal_blob.dig_P4 | (int16_t)b[12];
sc->sc_cal_blob.dig_P5 = (int16_t)b[15] << 8;
sc->sc_cal_blob.dig_P5 = sc->sc_cal_blob.dig_P5 | (int16_t)b[14];
sc->sc_cal_blob.dig_P6 = (int16_t)b[17] << 8;
sc->sc_cal_blob.dig_P6 = sc->sc_cal_blob.dig_P6 | (int16_t)b[16];
sc->sc_cal_blob.dig_P7 = (int16_t)b[19] << 8;
sc->sc_cal_blob.dig_P7 = sc->sc_cal_blob.dig_P7 | (int16_t)b[18];
sc->sc_cal_blob.dig_P8 = (int16_t)b[21] << 8;
sc->sc_cal_blob.dig_P8 = sc->sc_cal_blob.dig_P8 | (int16_t)b[20];
sc->sc_cal_blob.dig_P9 = (int16_t)b[23] << 8;
sc->sc_cal_blob.dig_P9 = sc->sc_cal_blob.dig_P9 | (int16_t)b[22];
}
static void
bmx280_store_raw_blob_h(struct bmx280_sc *sc, uint8_t *b) {
sc->sc_cal_blob.dig_H1 = (uint8_t)b[0];
sc->sc_cal_blob.dig_H2 = (int16_t)b[2] << 8;
sc->sc_cal_blob.dig_H2 = sc->sc_cal_blob.dig_H2 | (int16_t)b[1];
sc->sc_cal_blob.dig_H3 = (uint8_t)b[3];
sc->sc_cal_blob.dig_H4 = ((int16_t)((b[4] << 4) | (b[5] & 0x0F)));
sc->sc_cal_blob.dig_H5 = (int16_t)b[6] << 4;
sc->sc_cal_blob.dig_H5 = sc->sc_cal_blob.dig_H5 | (((int16_t)b[5] & 0x00f0) >> 4);
sc->sc_cal_blob.dig_H6 = (int8_t)b[7];
}
/* For the BMX280, a write consists of sending a I2C START, I2C SLAVE
* address and then pairs of registers and data until a I2C STOP is
* sent.
*/
static int
bmx280_write_register(i2c_tag_t tag, i2c_addr_t addr,
uint8_t *buf, size_t blen)
{
int error;
KASSERT(blen > 0);
/* XXX - there should be a KASSERT for blen at least
being an even number */
error = iic_exec(tag,I2C_OP_WRITE_WITH_STOP,addr,NULL,0,
buf,blen,0);
return error;
}
/* For the BMX280, a read consists of writing on the I2C bus
* a I2C START, I2C SLAVE address, then the starting register.
* If that works, then following will be another I2C START,
* I2C SLAVE address, followed by as many I2C reads that is
* desired and then a I2C STOP
*/
static int
bmx280_read_register(i2c_tag_t tag, i2c_addr_t addr, uint8_t *reg,
uint8_t *buf, size_t blen)
{
int error;
KASSERT(blen > 0);
error = iic_exec(tag,I2C_OP_WRITE,addr,reg,1,NULL,0,0);
if (error == 0) {
error = iic_exec(tag,I2C_OP_READ_WITH_STOP,addr,NULL,0,
buf,blen,0);
}
return error;
}
static int
bmx280_poke(i2c_tag_t tag, i2c_addr_t addr, bool matchdebug)
{
uint8_t reg = BMX280_REGISTER_ID;
uint8_t buf[1];
int error;
error = bmx280_read_register(tag, addr, ®, buf, 1);
if (matchdebug) {
printf("poke X 1: %d\n", error);
}
return error;
}
static int
bmx280_sysctl_init(struct bmx280_sc *sc)
{
int error;
const struct sysctlnode *cnode;
int sysctlroot_num, sysctlwait_num;
if ((error = sysctl_createv(&sc->sc_bmx280log, 0, NULL, &cnode,
0, CTLTYPE_NODE, device_xname(sc->sc_dev),
SYSCTL_DESCR("bmx280 controls"), NULL, 0, NULL, 0, CTL_HW,
CTL_CREATE, CTL_EOL)) != 0)
return error;
sysctlroot_num = cnode->sysctl_num;
#ifdef BMX280_DEBUG
if ((error = sysctl_createv(&sc->sc_bmx280log, 0, NULL, &cnode,
CTLFLAG_READWRITE, CTLTYPE_INT, "debug",
SYSCTL_DESCR("Debug level"), bmx280_verify_sysctl, 0,
&sc->sc_bmx280debug, 0, CTL_HW, sysctlroot_num, CTL_CREATE,
CTL_EOL)) != 0)
return error;
/* It would be nice to have a CTLTYPE_SHORT */
if ((error = sysctl_createv(&sc->sc_bmx280log, 0, NULL, &cnode,
CTLFLAG_READWRITE, CTLTYPE_BOOL, "dump_calibration",
SYSCTL_DESCR("Dumps the calibration values to the console"),
bmx280_verify_sysctl, 0,
&sc->sc_bmx280dump, 0, CTL_HW, sysctlroot_num, CTL_CREATE,
CTL_EOL)) != 0)
return error;
#endif
if ((error = sysctl_createv(&sc->sc_bmx280log, 0, NULL, &cnode,
CTLFLAG_READWRITE, CTLTYPE_INT, "readattempts",
SYSCTL_DESCR("Read attempts"), bmx280_verify_sysctl, 0,
&sc->sc_readattempts, 0, CTL_HW, sysctlroot_num, CTL_CREATE,
CTL_EOL)) != 0)
return error;
if ((error = sysctl_createv(&sc->sc_bmx280log, 0, NULL, &cnode,
CTLFLAG_READWRITE, CTLTYPE_INT, "osrs_t",
SYSCTL_DESCR("Temperature oversample"),
bmx280_verify_sysctl_osrs, 0, &sc->sc_osrs_t,
0, CTL_HW, sysctlroot_num, CTL_CREATE, CTL_EOL)) != 0)
return error;
if ((error = sysctl_createv(&sc->sc_bmx280log, 0, NULL, &cnode,
CTLFLAG_READWRITE, CTLTYPE_INT, "osrs_p",
SYSCTL_DESCR("Pressure oversample"),
bmx280_verify_sysctl_osrs, 0, &sc->sc_osrs_p,
0, CTL_HW, sysctlroot_num, CTL_CREATE, CTL_EOL)) != 0)
return error;
if (sc->sc_has_humidity) {
if ((error = sysctl_createv(&sc->sc_bmx280log, 0, NULL, &cnode,
CTLFLAG_READWRITE, CTLTYPE_INT, "osrs_h",
SYSCTL_DESCR("Humidity oversample"),
bmx280_verify_sysctl_osrs, 0, &sc->sc_osrs_h,
0, CTL_HW, sysctlroot_num, CTL_CREATE, CTL_EOL)) != 0)
return error;
}
if ((error = sysctl_createv(&sc->sc_bmx280log, 0, NULL, &cnode,
CTLFLAG_READWRITE, CTLTYPE_INT, "irr_samples",
SYSCTL_DESCR("IRR samples"),
bmx280_verify_sysctl_irr, 0, &sc->sc_irr_samples,
0, CTL_HW, sysctlroot_num, CTL_CREATE, CTL_EOL)) != 0)
return error;
if ((error = sysctl_createv(&sc->sc_bmx280log, 0, NULL, &cnode,
0, CTLTYPE_NODE, "waitfactor",
SYSCTL_DESCR("bmx280 wait factors"), NULL, 0, NULL, 0, CTL_HW,
sysctlroot_num, CTL_CREATE, CTL_EOL)) != 0)
return error;
sysctlwait_num = cnode->sysctl_num;
if ((error = sysctl_createv(&sc->sc_bmx280log, 0, NULL, &cnode,
CTLFLAG_READWRITE, CTLTYPE_INT, "t",
SYSCTL_DESCR("Temperature wait multiplier"),
bmx280_verify_sysctl, 0, &sc->sc_waitfactor_t,
0, CTL_HW, sysctlroot_num, sysctlwait_num, CTL_CREATE, CTL_EOL)) != 0)
return error;
if ((error = sysctl_createv(&sc->sc_bmx280log, 0, NULL, &cnode,
CTLFLAG_READWRITE, CTLTYPE_INT, "p",
SYSCTL_DESCR("Pressure wait multiplier"),
bmx280_verify_sysctl, 0, &sc->sc_waitfactor_p,
0, CTL_HW, sysctlroot_num, sysctlwait_num, CTL_CREATE, CTL_EOL)) != 0)
return error;
if (sc->sc_has_humidity) {
if ((error = sysctl_createv(&sc->sc_bmx280log, 0, NULL, &cnode,
CTLFLAG_READWRITE, CTLTYPE_INT, "h",
SYSCTL_DESCR("Humidity wait multiplier"),
bmx280_verify_sysctl, 0, &sc->sc_waitfactor_h,
0, CTL_HW, sysctlroot_num, sysctlwait_num, CTL_CREATE, CTL_EOL)) != 0)
return error;
}
return 0;
}
static int
bmx280_match(device_t parent, cfdata_t match, void *aux)
{
struct i2c_attach_args *ia = aux;
int error, match_result;
const bool matchdebug = false;
if (iic_use_direct_match(ia, match, NULL, &match_result))
return match_result;
/* indirect config - check for configured address */
if (ia->ia_addr != BMX280_TYPICAL_ADDR_1 &&
ia->ia_addr != BMX280_TYPICAL_ADDR_2)
return 0;
/*
* Check to see if something is really at this i2c address. This will
* keep phantom devices from appearing
*/
if (iic_acquire_bus(ia->ia_tag, 0) != 0) {
if (matchdebug)
printf("in match acquire bus failed\n");
return 0;
}
error = bmx280_poke(ia->ia_tag, ia->ia_addr, matchdebug);
iic_release_bus(ia->ia_tag, 0);
return error == 0 ? I2C_MATCH_ADDRESS_AND_PROBE : 0;
}
static void
bmx280_attach(device_t parent, device_t self, void *aux)
{
struct bmx280_sc *sc;
struct i2c_attach_args *ia;
int error, i;
uint8_t reg, chip_id;
uint8_t buf[2];
ia = aux;
sc = device_private(self);
sc->sc_dev = self;
sc->sc_tag = ia->ia_tag;
sc->sc_addr = ia->ia_addr;
sc->sc_bmx280debug = 0;
sc->sc_bmx280dump = false;
sc->sc_has_humidity = false;
sc->sc_readattempts = 25;
sc->sc_osrs_t = 1;
sc->sc_osrs_p = 4;
sc->sc_osrs_h = 1;
sc->sc_irr_samples = 1;
sc->sc_previous_irr = 0xff;
sc->sc_waitfactor_t = 6;
sc->sc_waitfactor_p = 2;
sc->sc_waitfactor_h = 2;
sc->sc_sme = NULL;
aprint_normal("\n");
mutex_init(&sc->sc_mutex, MUTEX_DEFAULT, IPL_NONE);
sc->sc_numsensors = __arraycount(bmx280_sensors);
if ((sc->sc_sme = sysmon_envsys_create()) == NULL) {
aprint_error_dev(self,
"Unable to create sysmon structure\n");
sc->sc_sme = NULL;
return;
}
error = iic_acquire_bus(sc->sc_tag, 0);
if (error) {
aprint_error_dev(self, "Could not acquire iic bus: %d\n",
error);
goto out;
}
buf[0] = BMX280_REGISTER_RESET;
buf[1] = BMX280_TRIGGER_RESET;
error = bmx280_write_register(sc->sc_tag, sc->sc_addr, buf, 2);
if (error) {
aprint_error_dev(self, "Failed to reset chip: %d\n",
error);
}
delay(30000);
reg = BMX280_REGISTER_ID;
error = bmx280_read_register(sc->sc_tag, sc->sc_addr, ®, &chip_id, 1);
if (error) {
aprint_error_dev(self, "Failed to read ID: %d\n",
error);
}
delay(1000);
DPRINTF(sc, 2, ("%s: read ID value: %02x\n",
device_xname(sc->sc_dev), chip_id));
if (chip_id == BMX280_ID_BME280) {
sc->sc_has_humidity = true;
}
if ((error = bmx280_sysctl_init(sc)) != 0) {
aprint_error_dev(self, "Can't setup sysctl tree (%d)\n", error);
goto out;
}
uint8_t raw_blob_tp[24];
reg = BMX280_REGISTER_DIG_T1;
error = bmx280_read_register(sc->sc_tag, sc->sc_addr, ®, raw_blob_tp, 24);
if (error) {
aprint_error_dev(self, "Failed to read the calibration registers for tp: %d\n",
error);
}
if (sc->sc_bmx280debug > 0) {
for(int _d = 0;_d < 24;_d++) {
DPRINTF(sc, 0, ("%s: %d %02x\n",
device_xname(sc->sc_dev), _d, raw_blob_tp[_d]));
}
}
bmx280_store_raw_blob_tp(sc,raw_blob_tp);
if (sc->sc_has_humidity) {
uint8_t raw_blob_h[8];
reg = BMX280_REGISTER_DIG_H1;
error = bmx280_read_register(sc->sc_tag, sc->sc_addr, ®, raw_blob_h, 1);
if (error) {
aprint_error_dev(self, "Failed to read the calibration registers for h1: %d\n",
error);
}
reg = BMX280_REGISTER_DIG_H2;
error = bmx280_read_register(sc->sc_tag, sc->sc_addr, ®, &raw_blob_h[1], 7);
if (error) {
aprint_error_dev(self, "Failed to read the calibration registers for h2 - h6: %d\n",
error);
}
if (sc->sc_bmx280debug > 0) {
for(int _d = 0;_d < 8;_d++) {
DPRINTF(sc, 0, ("%s: %d %02x\n",
device_xname(sc->sc_dev), _d, raw_blob_h[_d]));
}
}
bmx280_store_raw_blob_h(sc,raw_blob_h);
}
iic_release_bus(sc->sc_tag, 0);
if (error != 0) {
aprint_error_dev(self, "Unable to setup device\n");
goto out;
}
for (i = 0; i < sc->sc_numsensors; i++) {
if (sc->sc_has_humidity == false &&
bmx280_sensors[i].type == ENVSYS_SRELHUMIDITY) {
break;
}
strlcpy(sc->sc_sensors[i].desc, bmx280_sensors[i].desc,
sizeof(sc->sc_sensors[i].desc));
sc->sc_sensors[i].units = bmx280_sensors[i].type;
sc->sc_sensors[i].state = ENVSYS_SINVALID;
DPRINTF(sc, 2, ("%s: registering sensor %d (%s)\n", __func__, i,
sc->sc_sensors[i].desc));
error = sysmon_envsys_sensor_attach(sc->sc_sme,
&sc->sc_sensors[i]);
if (error) {
aprint_error_dev(self,
"Unable to attach sensor %d: %d\n", i, error);
goto out;
}
}
sc->sc_sme->sme_name = device_xname(sc->sc_dev);
sc->sc_sme->sme_cookie = sc;
sc->sc_sme->sme_refresh = bmx280_refresh;
DPRINTF(sc, 2, ("bmx280_attach: registering with envsys\n"));
if (sysmon_envsys_register(sc->sc_sme)) {
aprint_error_dev(self,
"unable to register with sysmon\n");
sysmon_envsys_destroy(sc->sc_sme);
sc->sc_sme = NULL;
return;
}
aprint_normal_dev(self, "Bosch Sensortec %s, Chip ID: 0x%02x\n",
(chip_id == BMX280_ID_BMP280) ? "BMP280" : (chip_id == BMX280_ID_BME280) ? "BME280" : "Unknown chip",
chip_id);
return;
out:
sysmon_envsys_destroy(sc->sc_sme);
sc->sc_sme = NULL;
}
/* The conversion algorithms are taken from the BMP280 datasheet. The
* same algorithms are used with the BME280.
*
* https://www.bosch-sensortec.com/media/boschsensortec/downloads/datasheets/bst-bmp280-ds001.pdf
*
* Section 3.11.3, page 21
*
*/
static int32_t
bmx280_compensate_T_int32(struct bmx280_calibration_blob *b,
int32_t adc_T,
int32_t *t_fine)
{
int32_t var1, var2, T;
var1 = ((((adc_T>>3) - ((int32_t)b->dig_T1<<1))) * ((int32_t)b->dig_T2)) >> 11;
var2 = (((((adc_T>>4) - ((int32_t)b->dig_T1)) * ((adc_T>>4) - ((int32_t)b->dig_T1))) >> 12) *
((int32_t)b->dig_T3)) >> 14;
*t_fine = var1 + var2;
T = (*t_fine * 5 + 128) >> 8;
return T;
}
/* Returns pressure in Pa as unsigned 32 bit integer in Q24.8 format (24 integer bits and 8 fractional bits).
* Output value of 24674867 represents 24674867/256 = 96386.2 Pa = 963.862 hPa
*/
static uint32_t
bmx280_compensate_P_int64(struct bmx280_calibration_blob *b,
int32_t adc_P,
int32_t t_fine)
{
int64_t var1, var2, p;
var1 = ((int64_t)t_fine) - 128000;
var2 = var1 * var1 * (int64_t)b->dig_P6;
var2 = var2 + ((var1*(int64_t)b->dig_P5)<<17);
var2 = var2 + (((int64_t)b->dig_P4)<<35);
var1 = ((var1 * var1 * (int64_t)b->dig_P3)>>8) + ((var1 * (int64_t)b->dig_P2)<<12);
var1 = (((((int64_t)1)<<47)+var1))*((int64_t)b->dig_P1)>>33;
if (var1 == 0) {
return 0; /* avoid exception caused by division by zero */
}
p = 1048576-adc_P;
p = (((p<<31)-var2)*3125)/var1;
var1 = (((int64_t)b->dig_P9) * (p>>13) * (p>>13)) >> 25;
var2 = (((int64_t)b->dig_P8) * p) >> 19;
p = ((p + var1 + var2) >> 8) + (((int64_t)b->dig_P7)<<4);
return (uint32_t)p;
}
/* Returns humidity in %RH as unsigned 32 bit integer in Q22.10 format (22 integer and 10 fractional bits).
*
* Output value of 47445 represents 47445/1024 = 46.333 %RH
*/
static uint32_t
bmx280_compensate_H_int32(struct bmx280_calibration_blob *b,
int32_t adc_H,
int32_t t_fine)
{
int32_t v_x1_u32r;
v_x1_u32r = (t_fine - ((int32_t)76800));
v_x1_u32r = (((((adc_H << 14) - (((int32_t)b->dig_H4) << 20) - (((int32_t)b->dig_H5) *
v_x1_u32r)) + ((int32_t)16384)) >> 15) * (((((((v_x1_u32r *
((int32_t)b->dig_H6)) >> 10) * (((v_x1_u32r * ((int32_t)b->dig_H3)) >> 11) +
((int32_t)32768))) >> 10) + ((int32_t)2097152)) * ((int32_t)b->dig_H2) +
8192) >> 14));
v_x1_u32r = (v_x1_u32r - (((((v_x1_u32r >> 15) * (v_x1_u32r >> 15)) >> 7) *
((int32_t)b->dig_H1)) >> 4));
v_x1_u32r = (v_x1_u32r < 0 ? 0 : v_x1_u32r);
v_x1_u32r = (v_x1_u32r > 419430400 ? 419430400 : v_x1_u32r);
return (uint32_t)(v_x1_u32r>>12);
}
static int
bmx280_set_control_and_trigger(struct bmx280_sc *sc,
uint8_t osrs_t_mask,
uint8_t osrs_p_mask,
uint8_t osrs_h_mask,
uint8_t filter_mask)
{
uint8_t cr[6];
int error;
int s = 0;
cr[0] = cr[1] = cr[2] = cr[3] = cr[4] = cr[5] = 0;
if (filter_mask != sc->sc_previous_irr) {
cr[s] = BMX280_REGISTER_CONFIG;
s++;
cr[s] = filter_mask << BMX280_CONFIG_FILTER_SHIFT;
s++;
sc->sc_previous_irr = filter_mask;
}
if (sc->sc_has_humidity) {
cr[s] = BMX280_REGISTER_CTRL_HUM;
s++;
cr[s] = osrs_h_mask;
s++;
}
cr[s] = BMX280_REGISTER_CTRL_MEAS;
s++;
cr[s] = osrs_t_mask << BMX280_CTRL_OSRS_T_SHIFT;
cr[s] = cr[s] | osrs_p_mask << BMX280_CTRL_OSRS_P_SHIFT;
cr[s] = cr[s] | BMX280_MODE_FORCED;
s++;
DPRINTF(sc, 2, ("%s: control register set up: num: %d ; %02x %02x ; %02x %02x ; %02x %02x\n",
device_xname(sc->sc_dev), s, cr[0], cr[1], cr[2], cr[3], cr[4], cr[5]));
error = bmx280_write_register(sc->sc_tag, sc->sc_addr, cr, s);
if (error) {
DPRINTF(sc, 2, ("%s: write control registers: %d\n",
device_xname(sc->sc_dev), error));
error = EINVAL;
}
/* The wait needed is not well documented, so this is somewhat of a guess.
* There is an attempt with this to only wait as long as needed.
*/
int p1, p2;
p1 = (osrs_t_mask * sc->sc_waitfactor_t) + (osrs_p_mask * sc->sc_waitfactor_p);
if (sc->sc_has_humidity) {
p1 = p1 + (osrs_h_mask * sc->sc_waitfactor_h);
}
p2 = mstohz(p1);
if (p2 == 0) {
p2 = 1;
}
/* Be careful with this... the print itself will cause extra delay */
DPRINTF(sc, 2, ("%s: p1: %d ; %d\n",
device_xname(sc->sc_dev), p1, p2));
kpause("b280mea",false,p2,NULL);
return error;
}
static int
bmx280_wait_for_data(struct bmx280_sc *sc)
{
uint8_t reg;
uint8_t running = 99;
int c = sc->sc_readattempts;
int error = 0, ierror;
reg = BMX280_REGISTER_STATUS;
do {
delay(1000);
ierror = bmx280_read_register(sc->sc_tag, sc->sc_addr, ®, &running, 1);
if (ierror) {
DPRINTF(sc, 2, ("%s: Refresh failed to read back status: %d\n",
device_xname(sc->sc_dev), ierror));
error = EINVAL;
break;
}
DPRINTF(sc, 2, ("%s: Refresh status read back: %02x\n",
device_xname(sc->sc_dev), running));
c--;
} while (c > 0 && (running & BMX280_STATUS_MEASURING_MASK));
return error;
}
static int
bmx280_read_data(struct bmx280_sc *sc,
int32_t *temp,
int32_t *press,
int32_t *hum,
bool justtemp)
{
int error = 0, ierror;
int rlen, rtstart, rpstart, rhstart;
int x_temp, x_press, x_hum;
uint8_t raw_press_temp_hum[8], reg;
raw_press_temp_hum[0] = raw_press_temp_hum[1] =
raw_press_temp_hum[2] = raw_press_temp_hum[3] =
raw_press_temp_hum[4] = raw_press_temp_hum[5] =
raw_press_temp_hum[6] = raw_press_temp_hum[7] = 0;
if (justtemp) {
reg = BMX280_REGISTER_TEMP_MSB;
rlen = 3;
rtstart = 0;
rpstart = 0;
rhstart = 0;
} else {
reg = BMX280_REGISTER_PRESS_MSB;
if (sc->sc_has_humidity == false) {
rlen = 6;
} else {
rlen = 8;
}
rtstart = 3;
rpstart = 0;
rhstart = 6;
}
DPRINTF(sc, 2, ("%s: read data: reg: %02x ; len: %d ; tstart: %d ; pstart: %d\n",
device_xname(sc->sc_dev), reg, rlen, rtstart, rpstart));
ierror = bmx280_read_register(sc->sc_tag, sc->sc_addr, ®, raw_press_temp_hum, rlen);
if (ierror) {
DPRINTF(sc, 2, ("%s: failed to read pressure and temp registers: %d\n",
device_xname(sc->sc_dev), ierror));
error = EINVAL;
goto out;
}
DPRINTF(sc, 2, ("%s: raw pressure, temp and hum: %02x %02x %02x - %02x %02x %02x - %02x %02x\n",
device_xname(sc->sc_dev),
raw_press_temp_hum[0], raw_press_temp_hum[1], raw_press_temp_hum[2],
raw_press_temp_hum[3], raw_press_temp_hum[4], raw_press_temp_hum[5],
raw_press_temp_hum[6],raw_press_temp_hum[7]));
x_temp = raw_press_temp_hum[rtstart] << 12;
x_temp = x_temp | (raw_press_temp_hum[rtstart + 1] << 4);
x_temp = x_temp | (raw_press_temp_hum[rtstart + 2] >> 4);
DPRINTF(sc, 1, ("%s: intermediate temp: %d (%04x)\n",
device_xname(sc->sc_dev), x_temp, x_temp));
*temp = x_temp;
*hum = 0;
*press = 0;
if (justtemp == false) {
x_press = raw_press_temp_hum[rpstart] << 12;
x_press = x_press | (raw_press_temp_hum[rpstart + 1] << 4);
x_press = x_press | (raw_press_temp_hum[rpstart + 2] >> 4);
DPRINTF(sc, 1, ("%s: intermediate pressure: %d (%04x)\n",
device_xname(sc->sc_dev), x_press, x_press));
*press = x_press;
}
if (sc->sc_has_humidity) {
x_hum = raw_press_temp_hum[rhstart] << 8;
x_hum = x_hum | raw_press_temp_hum[rhstart + 1];
DPRINTF(sc, 1, ("%s: intermediate humidity: %d (%02x)\n",
device_xname(sc->sc_dev), x_hum, x_hum));
*hum = x_hum;
}
out:
return error;
}
static void
bmx280_refresh(struct sysmon_envsys * sme, envsys_data_t * edata)
{
struct bmx280_sc *sc;
sc = sme->sme_cookie;
int error = 0;
int32_t t_fine;
int32_t m_temp, m_press, m_hum;
int32_t comp_temp;
uint32_t comp_press;
uint32_t comp_hum;
edata->state = ENVSYS_SINVALID;
/* Ya... just do this on a refresh... */
if (sc->sc_bmx280dump) {
DPRINTF(sc, 1, ("%s: dig_T1: %d %04x\n",__func__,sc->sc_cal_blob.dig_T1,sc->sc_cal_blob.dig_T1));
DPRINTF(sc, 1, ("%s: dig_T2: %d %04x\n",__func__,sc->sc_cal_blob.dig_T2,sc->sc_cal_blob.dig_T2));
DPRINTF(sc, 1, ("%s: dig_T3: %d %04x\n",__func__,sc->sc_cal_blob.dig_T3,sc->sc_cal_blob.dig_T3));
DPRINTF(sc, 1, ("%s: dig_P1: %d %04x\n",__func__,sc->sc_cal_blob.dig_P1,sc->sc_cal_blob.dig_P1));
DPRINTF(sc, 1, ("%s: dig_P2: %d %04x\n",__func__,sc->sc_cal_blob.dig_P2,sc->sc_cal_blob.dig_P2));
DPRINTF(sc, 1, ("%s: dig_P3: %d %04x\n",__func__,sc->sc_cal_blob.dig_P3,sc->sc_cal_blob.dig_P3));
DPRINTF(sc, 1, ("%s: dig_P4: %d %04x\n",__func__,sc->sc_cal_blob.dig_P4,sc->sc_cal_blob.dig_P4));
DPRINTF(sc, 1, ("%s: dig_P5: %d %04x\n",__func__,sc->sc_cal_blob.dig_P5,sc->sc_cal_blob.dig_P5));
DPRINTF(sc, 1, ("%s: dig_P6: %d %04x\n",__func__,sc->sc_cal_blob.dig_P6,sc->sc_cal_blob.dig_P6));
DPRINTF(sc, 1, ("%s: dig_P7: %d %04x\n",__func__,sc->sc_cal_blob.dig_P7,sc->sc_cal_blob.dig_P7));
DPRINTF(sc, 1, ("%s: dig_P8: %d %04x\n",__func__,sc->sc_cal_blob.dig_P8,sc->sc_cal_blob.dig_P8));
DPRINTF(sc, 1, ("%s: dig_P9: %d %04x\n",__func__,sc->sc_cal_blob.dig_P9,sc->sc_cal_blob.dig_P9));
if (sc->sc_has_humidity) {
DPRINTF(sc, 1, ("%s: dig_H1: %d %02x\n",__func__,sc->sc_cal_blob.dig_H1,sc->sc_cal_blob.dig_H1));
DPRINTF(sc, 1, ("%s: dig_H2: %d %04x\n",__func__,sc->sc_cal_blob.dig_H2,sc->sc_cal_blob.dig_H2));
DPRINTF(sc, 1, ("%s: dig_H3: %d %02x\n",__func__,sc->sc_cal_blob.dig_H3,sc->sc_cal_blob.dig_H3));
DPRINTF(sc, 1, ("%s: dig_H4: %d %04x\n",__func__,sc->sc_cal_blob.dig_H4,sc->sc_cal_blob.dig_H4));
DPRINTF(sc, 1, ("%s: dig_H5: %d %04x\n",__func__,sc->sc_cal_blob.dig_H5,sc->sc_cal_blob.dig_H5));
DPRINTF(sc, 1, ("%s: dig_H6: %d %02x\n",__func__,sc->sc_cal_blob.dig_H6,sc->sc_cal_blob.dig_H6));
}
sc->sc_bmx280dump = false;
}
mutex_enter(&sc->sc_mutex);
error = iic_acquire_bus(sc->sc_tag, 0);
if (error) {
DPRINTF(sc, 2, ("%s: Could not acquire i2c bus: %x\n",
device_xname(sc->sc_dev), error));
goto out;
}
if (error == 0) {
switch (edata->sensor) {
case BMX280_TEMP_SENSOR:
/* A temperature reading does not need pressure */
error = bmx280_set_control_and_trigger(sc,
bmx280_osrs_text_to_mask(sc->sc_osrs_t),
0,
0,
bmx280_irr_text_to_mask(sc->sc_irr_samples));
if (error == 0) {
error = bmx280_wait_for_data(sc);
if (error == 0) {
error = bmx280_read_data(sc, &m_temp, &m_press, &m_hum, true);
if (error == 0) {
comp_temp = bmx280_compensate_T_int32(&sc->sc_cal_blob, m_temp, &t_fine);
DPRINTF(sc, 1, ("%s: Refresh compensated temp: %d - t_fine: %d\n",
device_xname(sc->sc_dev), comp_temp, t_fine));
/* comp_temp is in Celcius * 100. This converts it to microkelvin */
uint32_t q;
q = (uint32_t)comp_temp;
q = q + 27315;
q = q * 10000;
DPRINTF(sc, 1, ("%s: Refresh Q: %d\n", __func__, q));
edata->value_cur = q;
edata->state = ENVSYS_SVALID;
}
}
}
break;
case BMX280_PRESSURE_SENSOR:
/* Pressure needs the temp too */
error = bmx280_set_control_and_trigger(sc,
bmx280_osrs_text_to_mask(sc->sc_osrs_t),
bmx280_osrs_text_to_mask(sc->sc_osrs_p),
0,
bmx280_irr_text_to_mask(sc->sc_irr_samples));
if (error == 0) {
error = bmx280_wait_for_data(sc);
if (error == 0) {
error = bmx280_read_data(sc, &m_temp, &m_press, &m_hum, false);
if (error == 0) {
comp_temp = bmx280_compensate_T_int32(&sc->sc_cal_blob, m_temp, &t_fine);
DPRINTF(sc, 1, ("%s: Refresh compensated temp for pressure: %d - t_fine: %d\n",
device_xname(sc->sc_dev), comp_temp, t_fine));
comp_press = bmx280_compensate_P_int64(&sc->sc_cal_blob, m_press, t_fine);
DPRINTF(sc, 1, ("%s: Refresh compensated pressure: %d\n",
device_xname(sc->sc_dev), comp_press));
uint32_t q;
q = comp_press;
q = q / 256;
q = q * 100;
DPRINTF(sc, 1, ("%s: Refresh pressure Q: %d\n", __func__, q));
edata->value_cur = q;
edata->state = ENVSYS_SVALID;
}
}
}
break;
case BMX280_HUMIDITY_SENSOR:
/* Humidity wants temperature */
error = bmx280_set_control_and_trigger(sc,
bmx280_osrs_text_to_mask(sc->sc_osrs_t),
0,
bmx280_osrs_text_to_mask(sc->sc_osrs_h),
bmx280_irr_text_to_mask(sc->sc_irr_samples));
if (error == 0) {
error = bmx280_wait_for_data(sc);
if (error == 0) {
error = bmx280_read_data(sc, &m_temp, &m_press, &m_hum, false);
if (error == 0) {
comp_temp = bmx280_compensate_T_int32(&sc->sc_cal_blob, m_temp, &t_fine);
DPRINTF(sc, 1, ("%s: Refresh compensated temp for humidity: %d - t_fine: %d\n",
device_xname(sc->sc_dev), comp_temp, t_fine));
comp_hum = bmx280_compensate_H_int32(&sc->sc_cal_blob, m_hum, t_fine);
DPRINTF(sc, 2, ("%s: Refresh compensated humidity: %d\n",
device_xname(sc->sc_dev), comp_hum));
uint64_t q;
q = (uint64_t)comp_hum * 1000000;
DPRINTF(sc, 1, ("%s: Refresh humidity Q 1: %jd\n", __func__, (uintmax_t)q));
q = q / 1024;
DPRINTF(sc, 1, ("%s: Refresh humidity Q 2: %jd\n", __func__, (uintmax_t)q));
edata->value_cur = (uint32_t) q;
edata->state = ENVSYS_SVALID;
}
}
}
break;
}
}
if (error) {
DPRINTF(sc, 2, ("%s: Failed to get new status in refresh %d\n",
device_xname(sc->sc_dev), error));
}
iic_release_bus(sc->sc_tag, 0);
out:
mutex_exit(&sc->sc_mutex);
}
static int
bmx280_detach(device_t self, int flags)
{
struct bmx280_sc *sc;
sc = device_private(self);
mutex_enter(&sc->sc_mutex);
/* Remove the sensors */
if (sc->sc_sme != NULL) {
sysmon_envsys_unregister(sc->sc_sme);
sc->sc_sme = NULL;
}
mutex_exit(&sc->sc_mutex);
/* Remove the sysctl tree */
sysctl_teardown(&sc->sc_bmx280log);
/* Remove the mutex */
mutex_destroy(&sc->sc_mutex);
return 0;
}
MODULE(MODULE_CLASS_DRIVER, bmx280thp, "iic,sysmon_envsys");
#ifdef _MODULE
#include "ioconf.c"
#endif
static int
bmx280thp_modcmd(modcmd_t cmd, void *opaque)
{
switch (cmd) {
case MODULE_CMD_INIT:
#ifdef _MODULE
return config_init_component(cfdriver_ioconf_bmx280thp,
cfattach_ioconf_bmx280thp, cfdata_ioconf_bmx280thp);
#else
return 0;
#endif
case MODULE_CMD_FINI:
#ifdef _MODULE
return config_fini_component(cfdriver_ioconf_bmx280thp,
cfattach_ioconf_bmx280thp, cfdata_ioconf_bmx280thp);
#else
return 0;
#endif
default:
return ENOTTY;
}
}
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