Patch "iio: bmi160: Fix time needed to sleep after command execution" has been added to the 4.9-stable tree

Patch "iio: bmi160: Fix time needed to sleep after command execution" has been added to the 4.9-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    iio: bmi160: Fix time needed to sleep after command execution

to the 4.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     iio-bmi160-fix-time-needed-to-sleep-after-command-execution.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 01d1f7a99e457952aa51849ed7c1cc4ced7bca4b Mon Sep 17 00:00:00 2001
From: Marcin Niestroj <m.niestroj@grinn-global.com>
Date: Thu, 8 Dec 2016 15:22:58 +0100
Subject: iio: bmi160: Fix time needed to sleep after command execution

From: Marcin Niestroj <m.niestroj@grinn-global.com>

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@grinn-global.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 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;
 }


Patches currently in stable-queue which might be from m.niestroj@grinn-global.com are

queue-4.9/iio-bmi160-fix-time-needed-to-sleep-after-command-execution.patch