staging: iio: tsl2x7x: make proximity sensor function correctly

The bits for setting up the proximity diode were not setup correctly and
this was causing the proximity sensor to not function correctly. This
patch sets up the correct bit mask in tsl2x7x_chip_on() based on what
the data sheet expects. From page 35 of the TSL2771 data sheet:
https://ams.com/eng/content/download/250264/976045/file/TSL2771_DS000105_3-00.pdf

- Bits 0-1 is the ALS gain control
- Bits 2-3 is reserved (The proximity gain control on other tsl2x7x chips)
- Bits 4-5 is the proximity diode select
- Bits 6-7 is the LED drive strength

tsl2x7x_chip_on() had the power and diode hardcoded, so these are
extracted out into the settings so that these fields can be configured
in the platform data.

The default prox_gain is changed from 1 (2X gain) to 0 (1X gain) since
the proximity gain control on the TSL2771, TMD2771, and other chips have
these fields listed as reserved, and to write 0 into those bits.

Verified that the proximity sensor now works correctly on a TSL2771
hooked up to a Raspberry Pi 2.

Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/staging/iio/light/tsl2x7x.c b/drivers/staging/iio/light/tsl2x7x.c
index c2b08a5d5b0ec2c259f6efe4dd0dc6c151a46b67..82681300e1062b96d4c413095f16060de37c1756 100644 (file)
--- a/drivers/staging/iio/light/tsl2x7x.c
+++ b/drivers/staging/iio/light/tsl2x7x.c
@@ -109,15 +109,15 @@
 #define TSL2X7X_CNTL_INTPROXPON_ENBL   0x2F
 
 /*Prox diode to use */
-#define TSL2X7X_DIODE0                 0x10
-#define TSL2X7X_DIODE1                 0x20
-#define TSL2X7X_DIODE_BOTH             0x30
+#define TSL2X7X_DIODE0                 0x01
+#define TSL2X7X_DIODE1                 0x02
+#define TSL2X7X_DIODE_BOTH             0x03
 
 /* LED Power */
 #define TSL2X7X_100_mA                 0x00
-#define TSL2X7X_50_mA                  0x40
-#define TSL2X7X_25_mA                  0x80
-#define TSL2X7X_13_mA                  0xD0
+#define TSL2X7X_50_mA                  0x01
+#define TSL2X7X_25_mA                  0x02
+#define TSL2X7X_13_mA                  0x03
 #define TSL2X7X_MAX_TIMER_CNT          0xFF
 
 #define TSL2X7X_MIN_ITIME              3
@@ -228,7 +228,7 @@ static const struct tsl2x7x_settings tsl2x7x_default_settings = {
        .als_time = 219, /* 101 ms */
        .als_gain = 0,
        .prx_time = 254, /* 5.4 ms */
-       .prox_gain = 1,
+       .prox_gain = 0,
        .wait_time = 245,
        .prox_config = 0,
        .als_gain_trim = 1000,
@@ -240,7 +240,9 @@ static const struct tsl2x7x_settings tsl2x7x_default_settings = {
        .prox_thres_low  = 0,
        .prox_thres_high = 512,
        .prox_max_samples_cal = 30,
-       .prox_pulse_count = 8
+       .prox_pulse_count = 8,
+       .prox_diode = TSL2X7X_DIODE1,
+       .prox_power = TSL2X7X_100_mA
 };
 
 static const s16 tsl2x7x_als_gain[] = {
@@ -659,9 +661,10 @@ static int tsl2x7x_chip_on(struct iio_dev *indio_dev)
 
        /* Set the gain based on tsl2x7x_settings struct */
        chip->tsl2x7x_config[TSL2X7X_GAIN] =
-               chip->settings.als_gain |
-                       (TSL2X7X_100_mA | TSL2X7X_DIODE1) |
-                       (chip->settings.prox_gain << 2);
+               (chip->settings.als_gain & 0xFF) |
+               ((chip->settings.prox_gain & 0xFF) << 2) |
+               (chip->settings.prox_diode << 4) |
+               (chip->settings.prox_power << 6);
 
        /* set chip struct re scaling and saturation */
        chip->als_saturation = als_count * 922; /* 90% of full scale */

diff --git a/drivers/staging/iio/light/tsl2x7x.h b/drivers/staging/iio/light/tsl2x7x.h
index 6624cbca7a83cbcbf32b995f947328b853c84e7a..28b0e7fdc9b8f1e315f4ba18697e2d67f24a206b 100644 (file)
--- a/drivers/staging/iio/light/tsl2x7x.h
+++ b/drivers/staging/iio/light/tsl2x7x.h
@@ -78,6 +78,8 @@ struct tsl2x7x_settings {
        int prox_thres_high;
        int prox_pulse_count;
        int prox_max_samples_cal;
+       int prox_diode;
+       int prox_power;
 };
 
 /**