[src/trunk]: src/sys/dev/i2c Correct the humidity conversion for the BME280

[brad <brad%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/d079e794a9f6
branches:  trunk
changeset: 372482:d079e794a9f6
user:      brad <brad%NetBSD.org@localhost>
date:      Thu Dec 01 00:47:51 2022 +0000

description:
Correct the humidity conversion for the BME280

diffstat:

 sys/dev/i2c/bmx280.c |  31 ++++++++++++++++++++++---------
 1 files changed, 22 insertions(+), 9 deletions(-)

diffs (77 lines):

diff -r 768dd7a3a89d -r d079e794a9f6 sys/dev/i2c/bmx280.c
--- a/sys/dev/i2c/bmx280.c      Thu Dec 01 00:43:27 2022 +0000
+++ b/sys/dev/i2c/bmx280.c      Thu Dec 01 00:47:51 2022 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: bmx280.c,v 1.4 2022/11/24 21:07:05 brad Exp $  */
+/*     $NetBSD: bmx280.c,v 1.5 2022/12/01 00:47:51 brad Exp $  */
 
 /*
  * Copyright (c) 2022 Brad Spencer <brad%anduin.eldar.org@localhost>
@@ -17,7 +17,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: bmx280.c,v 1.4 2022/11/24 21:07:05 brad Exp $");
+__KERNEL_RCSID(0, "$NetBSD: bmx280.c,v 1.5 2022/12/01 00:47:51 brad Exp $");
 
 /*
   Driver for the Bosch BMP280/BME280 temperature, humidity (sometimes) and
@@ -277,8 +277,7 @@
        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[5] & 0x000f) << 8;
-       sc->sc_cal_blob.dig_H4 = sc->sc_cal_blob.dig_H4 | (int16_t)b[4];
+       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];
@@ -566,6 +565,13 @@
                    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) {
@@ -585,6 +591,13 @@
                            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);
        }
 
@@ -1049,15 +1062,15 @@
                                                DPRINTF(sc, 2, ("%s: Refresh compensated humidity: %d\n",
                                                    device_xname(sc->sc_dev), comp_hum));
 
-                                               uint32_t q;
+                                               uint64_t q;
 
-                                               q = comp_hum;
+                                               q = (uint64_t)comp_hum * 1000000;
+                                               DPRINTF(sc, 1, ("%s: Refresh humidity Q 1: %lld\n", __func__, q));
                                                q = q / 1024;
-                                               q = q * 100; /* XXX - this probably is not correct */
 
-                                               DPRINTF(sc, 1, ("%s: Refresh humidity Q: %d\n", __func__, q));
+                                               DPRINTF(sc, 1, ("%s: Refresh humidity Q 2: %lld\n", __func__, q));
 
-                                               edata->value_cur = q;
+                                               edata->value_cur = (uint32_t) q;
                                                edata->state = ENVSYS_SVALID;
                                        }
                                }