[PATCH 4.9 003/206] iio: bmi160: Fix time needed to sleep after command execution

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Marcin Niestroj <m.niestroj@xxxxxxxxxxxxxxxx>

commit 01d1f7a99e457952aa51849ed7c1cc4ced7bca4b upstream.

Datasheet specifies typical and maximum execution times for which CMD
register is occupied after previous command execution. We took these
values as minimum and maximum time for usleep_range() call before making
a new command execution.

To be sure, that the CMD register is no longer occupied we need to wait
*at least* the maximum time specified by datasheet.

Signed-off-by: Marcin Niestroj <m.niestroj@xxxxxxxxxxxxxxxx>
Signed-off-by: Jonathan Cameron <jic23@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/iio/imu/bmi160/bmi160_core.c |   25 ++++++-------------------
 1 file changed, 6 insertions(+), 19 deletions(-)

--- a/drivers/iio/imu/bmi160/bmi160_core.c
+++ b/drivers/iio/imu/bmi160/bmi160_core.c
@@ -66,10 +66,8 @@
 
 #define BMI160_REG_DUMMY		0x7F
 
-#define BMI160_ACCEL_PMU_MIN_USLEEP	3200
-#define BMI160_ACCEL_PMU_MAX_USLEEP	3800
-#define BMI160_GYRO_PMU_MIN_USLEEP	55000
-#define BMI160_GYRO_PMU_MAX_USLEEP	80000
+#define BMI160_ACCEL_PMU_MIN_USLEEP	3800
+#define BMI160_GYRO_PMU_MIN_USLEEP	80000
 #define BMI160_SOFTRESET_USLEEP		1000
 
 #define BMI160_CHANNEL(_type, _axis, _index) {			\
@@ -151,20 +149,9 @@ static struct bmi160_regs bmi160_regs[]
 	},
 };
 
-struct bmi160_pmu_time {
-	unsigned long min;
-	unsigned long max;
-};
-
-static struct bmi160_pmu_time bmi160_pmu_time[] = {
-	[BMI160_ACCEL] = {
-		.min = BMI160_ACCEL_PMU_MIN_USLEEP,
-		.max = BMI160_ACCEL_PMU_MAX_USLEEP
-	},
-	[BMI160_GYRO] = {
-		.min = BMI160_GYRO_PMU_MIN_USLEEP,
-		.max = BMI160_GYRO_PMU_MIN_USLEEP,
-	},
+static unsigned long bmi160_pmu_time[] = {
+	[BMI160_ACCEL] = BMI160_ACCEL_PMU_MIN_USLEEP,
+	[BMI160_GYRO] = BMI160_GYRO_PMU_MIN_USLEEP,
 };
 
 struct bmi160_scale {
@@ -289,7 +276,7 @@ int bmi160_set_mode(struct bmi160_data *
 	if (ret < 0)
 		return ret;
 
-	usleep_range(bmi160_pmu_time[t].min, bmi160_pmu_time[t].max);
+	usleep_range(bmi160_pmu_time[t], bmi160_pmu_time[t] + 1000);
 
 	return 0;
 }