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iio: hid-sensor-attributes: Fix divisions for 32-bit platforms 

The commit 473d12f763

  ("iio: hid-sensor-attributes: Convert to use int_pow()")

converted to use generic int_pow() helper. Though, the generic one returns
64-bit value and, in cases when it is used as divisor, it compels 64-bit
division from compiler.

In order to fix this, introduce a temporary 32-bit variable to hold the result
of int_pow() and use it as divisor afterwards.

In couple of cases, replace int_pow() with a predefined unit factors for time
and frequency.

Fixes: 473d12f763 ("iio: hid-sensor-attributes: Convert to use int_pow()")
Reported-by: kbuild test robot <lkp@intel.com>
Reported-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Link: https://lore.kernel.org/r/20190905112759.13035-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Andy Shevchenko 2019-09-05 14:27:59 +03:00 committed by Greg Kroah-Hartman
parent 618f40ea02
commit f6897deef4
1 changed files with 28 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

42
drivers/iio/common/hid-sensors/hid-sensor-attributes.c
View File

@ -10,10 +10,14 @@
#include <linux/irq.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/time.h>
#include <linux/hid-sensor-hub.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#define HZ_PER_MHZ 1000000L
static struct {
u32 usage_id;
int unit; /* 0 for default others from HID sensor spec */
@ -93,8 +97,10 @@ static void simple_div(int dividend, int divisor, int *whole,
static void split_micro_fraction(unsigned int no, int exp, int *val1, int *val2)
{
*val1 = no / int_pow(10, exp);
*val2 = no % int_pow(10, exp) * int_pow(10, 6 - exp);
int divisor = int_pow(10, exp);
*val1 = no / divisor;
*val2 = no % divisor * int_pow(10, 6 - exp);
}
/*
@ -129,6 +135,7 @@ static void convert_from_vtf_format(u32 value, int size, int exp,
static u32 convert_to_vtf_format(int size, int exp, int val1, int val2)
{
int divisor;
u32 value;
int sign = 1;
@ -136,10 +143,13 @@ static u32 convert_to_vtf_format(int size, int exp, int val1, int val2)
sign = -1;
exp = hid_sensor_convert_exponent(exp);
if (exp < 0) {
divisor = int_pow(10, 6 + exp);
value = abs(val1) * int_pow(10, -exp);
value += abs(val2) / int_pow(10, 6 + exp);
} else
value = abs(val1) / int_pow(10, exp);
value += abs(val2) / divisor;
} else {
divisor = int_pow(10, exp);
value = abs(val1) / divisor;
}
if (sign < 0)
value = ((1LL << (size * 8)) - value);
@ -202,12 +212,12 @@ int hid_sensor_write_samp_freq_value(struct hid_sensor_common *st,
if (val1 < 0 || val2 < 0)
return -EINVAL;
value = val1 * int_pow(10, 6) + val2;
value = val1 * HZ_PER_MHZ + val2;
if (value) {
if (st->poll.units == HID_USAGE_SENSOR_UNITS_MILLISECOND)
value = int_pow(10, 9) / value;
value = NSEC_PER_SEC / value;
else if (st->poll.units == HID_USAGE_SENSOR_UNITS_SECOND)
value = int_pow(10, 6) / value;
value = USEC_PER_SEC / value;
else
value = 0;
}
@ -296,6 +306,7 @@ EXPORT_SYMBOL(hid_sensor_write_raw_hyst_value);
static void adjust_exponent_nano(int *val0, int *val1, int scale0,
int scale1, int exp)
{
int divisor;
int i;
int x;
int res;
@ -309,9 +320,10 @@ static void adjust_exponent_nano(int *val0, int *val1, int scale0,
return;
}
for (i = 0; i < exp; ++i) {
x = scale1 / int_pow(10, 8 - i);
divisor = int_pow(10, 8 - i);
x = scale1 / divisor;
res += int_pow(10, exp - 1 - i) * x;
scale1 = scale1 % int_pow(10, 8 - i);
scale1 = scale1 % divisor;
}
*val0 += res;
*val1 = scale1 * int_pow(10, exp);
@ -321,13 +333,15 @@ static void adjust_exponent_nano(int *val0, int *val1, int scale0,
*val0 = *val1 = 0;
return;
}
*val0 = scale0 / int_pow(10, exp);
rem = scale0 % int_pow(10, exp);
divisor = int_pow(10, exp);
*val0 = scale0 / divisor;
rem = scale0 % divisor;
res = 0;
for (i = 0; i < (9 - exp); ++i) {
x = scale1 / int_pow(10, 8 - i);
divisor = int_pow(10, 8 - i);
x = scale1 / divisor;
res += int_pow(10, 8 - exp - i) * x;
scale1 = scale1 % int_pow(10, 8 - i);
scale1 = scale1 % divisor;
}
*val1 = rem * int_pow(10, 9 - exp) + res;
} else {