This is a note to let you know that I've just added the patch titled
iio: accel: bma180: Fix BMA25x bandwidth register values
to my staging git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git
in the staging-next branch.
The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)
The patch will also be merged in the next major kernel release
during the merge window.
If you have any questions about this process, please let me know.
>From 8090d67421ddab0ae932abab5a60200598bf0bbb Mon Sep 17 00:00:00 2001
From: Stephan Gerhold <stephan@xxxxxxxxxxx>
Date: Wed, 26 May 2021 11:44:07 +0200
Subject: iio: accel: bma180: Fix BMA25x bandwidth register values
MIME-Version: 1.0
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According to the BMA253 datasheet [1] and BMA250 datasheet [2] the
bandwidth value for BMA25x should be set as 01xxx:
"Settings 00xxx result in a bandwidth of 7.81 Hz; [...]
It is recommended [...] to use the range from ´01000b´ to ´01111b´
only in order to be compatible with future products."
However, at the moment the drivers sets bandwidth values from 0 to 6,
which is not recommended and always results into 7.81 Hz bandwidth
according to the datasheet.
Fix this by introducing a bw_offset = 8 = 01000b for BMA25x,
so the additional bit is always set for BMA25x.
[1]: https://www.bosch-sensortec.com/media/boschsensortec/downloads/datasheets/bst-bma253-ds000.pdf
[2]: https://datasheet.octopart.com/BMA250-Bosch-datasheet-15540103.pdf
Cc: Peter Meerwald <pmeerw@xxxxxxxxxx>
Fixes: 2017cff24cc0 ("iio:bma180: Add BMA250 chip support")
Signed-off-by: Stephan Gerhold <stephan@xxxxxxxxxxx>
Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20210526094408.34298-2-stephan@xxxxxxxxxxx
Cc: <Stable@xxxxxxxxxxxxxxx>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
---
drivers/iio/accel/bma180.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/drivers/iio/accel/bma180.c b/drivers/iio/accel/bma180.c
index 4a07e60c0e21..e7c6b3096cb7 100644
--- a/drivers/iio/accel/bma180.c
+++ b/drivers/iio/accel/bma180.c
@@ -55,7 +55,7 @@ struct bma180_part_info {
u8 int_reset_reg, int_reset_mask;
u8 sleep_reg, sleep_mask;
- u8 bw_reg, bw_mask;
+ u8 bw_reg, bw_mask, bw_offset;
u8 scale_reg, scale_mask;
u8 power_reg, power_mask, lowpower_val;
u8 int_enable_reg, int_enable_mask;
@@ -127,6 +127,7 @@ struct bma180_part_info {
#define BMA250_RANGE_MASK GENMASK(3, 0) /* Range of accel values */
#define BMA250_BW_MASK GENMASK(4, 0) /* Accel bandwidth */
+#define BMA250_BW_OFFSET 8
#define BMA250_SUSPEND_MASK BIT(7) /* chip will sleep */
#define BMA250_LOWPOWER_MASK BIT(6)
#define BMA250_DATA_INTEN_MASK BIT(4)
@@ -143,6 +144,7 @@ struct bma180_part_info {
#define BMA254_RANGE_MASK GENMASK(3, 0) /* Range of accel values */
#define BMA254_BW_MASK GENMASK(4, 0) /* Accel bandwidth */
+#define BMA254_BW_OFFSET 8
#define BMA254_SUSPEND_MASK BIT(7) /* chip will sleep */
#define BMA254_LOWPOWER_MASK BIT(6)
#define BMA254_DATA_INTEN_MASK BIT(4)
@@ -287,7 +289,8 @@ static int bma180_set_bw(struct bma180_data *data, int val)
for (i = 0; i < data->part_info->num_bw; ++i) {
if (data->part_info->bw_table[i] == val) {
ret = bma180_set_bits(data, data->part_info->bw_reg,
- data->part_info->bw_mask, i);
+ data->part_info->bw_mask,
+ i + data->part_info->bw_offset);
if (ret) {
dev_err(&data->client->dev,
"failed to set bandwidth\n");
@@ -880,6 +883,7 @@ static const struct bma180_part_info bma180_part_info[] = {
.sleep_mask = BMA250_SUSPEND_MASK,
.bw_reg = BMA250_BW_REG,
.bw_mask = BMA250_BW_MASK,
+ .bw_offset = BMA250_BW_OFFSET,
.scale_reg = BMA250_RANGE_REG,
.scale_mask = BMA250_RANGE_MASK,
.power_reg = BMA250_POWER_REG,
@@ -909,6 +913,7 @@ static const struct bma180_part_info bma180_part_info[] = {
.sleep_mask = BMA254_SUSPEND_MASK,
.bw_reg = BMA254_BW_REG,
.bw_mask = BMA254_BW_MASK,
+ .bw_offset = BMA254_BW_OFFSET,
.scale_reg = BMA254_RANGE_REG,
.scale_mask = BMA254_RANGE_MASK,
.power_reg = BMA254_POWER_REG,
--
2.32.0
