| Message ID | 20190905112759.13035-1-andriy.shevchenko@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v1] iio: hid-sensor-attributes: Fix divisions for 32-bit platforms | expand |
On Thu, 2019-09-05 at 14:27 +0300, Andy Shevchenko wrote: > The commit 473d12f7638c > > ("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: 473d12f7638c ("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> > --- > .../hid-sensors/hid-sensor-attributes.c | 42 ++++++++++++----- > -- > 1 file changed, 28 insertions(+), 14 deletions(-) > > diff --git a/drivers/iio/common/hid-sensors/hid-sensor-attributes.c > b/drivers/iio/common/hid-sensors/hid-sensor-attributes.c > index b9dd19b34267..442ff787f7af 100644 > --- a/drivers/iio/common/hid-sensors/hid-sensor-attributes.c > +++ b/drivers/iio/common/hid-sensors/hid-sensor-attributes.c > @@ -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 {
diff --git a/drivers/iio/common/hid-sensors/hid-sensor-attributes.c b/drivers/iio/common/hid-sensors/hid-sensor-attributes.c index b9dd19b34267..442ff787f7af 100644 --- a/drivers/iio/common/hid-sensors/hid-sensor-attributes.c +++ b/drivers/iio/common/hid-sensors/hid-sensor-attributes.c @@ -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 {
The commit 473d12f7638c ("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: 473d12f7638c ("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> --- .../hid-sensors/hid-sensor-attributes.c | 42 ++++++++++++------- 1 file changed, 28 insertions(+), 14 deletions(-)