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* [PATCH] iio: Fixed IIO_VAL_FRACTIONAL calcuation for negative values
@ 2020-08-20 18:09 Anand Ashok Dumbre
  2020-08-22 10:56 ` Jonathan Cameron
  0 siblings, 1 reply; 4+ messages in thread
From: Anand Ashok Dumbre @ 2020-08-20 18:09 UTC (permalink / raw)
  To: jic23, knaack.h, lars, pmeerw, michal.simek, git, linux-iio,
	linux-arm-kernel, linux-kernel
  Cc: anandash, Anand Ashok Dumbre

This patch fixes IIO_VAL_FRACTIONAL calculation for negative
values where the exponent is 0.

Signed-off-by: Anand Ashok Dumbre <anand.ashok.dumbre@xilinx.com>
---
 drivers/iio/industrialio-core.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index f72c2dc..cd43b17 100644
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -554,6 +554,7 @@ static ssize_t __iio_format_value(char *buf, size_t len, unsigned int type,
 {
        unsigned long long tmp;
        int tmp0, tmp1;
+       s64 tmp2;
        bool scale_db = false;

        switch (type) {
@@ -576,10 +577,13 @@ static ssize_t __iio_format_value(char *buf, size_t len, unsigned int type,
                else
                        return snprintf(buf, len, "%d.%09u", vals[0], vals[1]);
        case IIO_VAL_FRACTIONAL:
-               tmp = div_s64((s64)vals[0] * 1000000000LL, vals[1]);
+               tmp2 = div_s64((s64)vals[0] * 1000000000LL, vals[1]);
                tmp1 = vals[1];
-               tmp0 = (int)div_s64_rem(tmp, 1000000000, &tmp1);
-               return snprintf(buf, len, "%d.%09u", tmp0, abs(tmp1));
+               tmp0 = (int)div_s64_rem(tmp2, 1000000000, &tmp1);
+               if ((tmp2 < 0) && (tmp0 == 0))
+                       return snprintf(buf, len, "-%d.%09u", tmp0, abs(tmp1));
+               else
+                       return snprintf(buf, len, "%d.%09u", tmp0, abs(tmp1));
        case IIO_VAL_FRACTIONAL_LOG2:
                tmp = shift_right((s64)vals[0] * 1000000000LL, vals[1]);
                tmp0 = (int)div_s64_rem(tmp, 1000000000LL, &tmp1);
--
2.7.4

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^ permalink raw reply	[flat|nested] 4+ messages in thread
* [PATCH] iio: Fixed IIO_VAL_FRACTIONAL calcuation for negative values
@ 2020-08-20  8:31 Anand Ashok Dumbre
  2020-08-20 13:09 ` Andy Shevchenko
  0 siblings, 1 reply; 4+ messages in thread
From: Anand Ashok Dumbre @ 2020-08-20  8:31 UTC (permalink / raw)
  To: jic23, knaack.h, lars, pmeerw, michal.simek, git, linux-iio,
	linux-arm-kernel, linux-kernel
  Cc: Anand Ashok Dumbre

This patch fixes IIO_VAL_FRACTIONAL calculation for negative
values where the exponent is 0.

Signed-off-by: Anand Ashok Dumbre <anand.ashok.dumbre@xilinx.com>
---
 drivers/iio/industrialio-core.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index f72c2dc..cd43b17 100644
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -554,6 +554,7 @@ static ssize_t __iio_format_value(char *buf, size_t len, unsigned int type,
 {
        unsigned long long tmp;
        int tmp0, tmp1;
+       s64 tmp2;
        bool scale_db = false;

        switch (type) {
@@ -576,10 +577,13 @@ static ssize_t __iio_format_value(char *buf, size_t len, unsigned int type,
                else
                        return snprintf(buf, len, "%d.%09u", vals[0], vals[1]);
        case IIO_VAL_FRACTIONAL:
-               tmp = div_s64((s64)vals[0] * 1000000000LL, vals[1]);
+               tmp2 = div_s64((s64)vals[0] * 1000000000LL, vals[1]);
                tmp1 = vals[1];
-               tmp0 = (int)div_s64_rem(tmp, 1000000000, &tmp1);
-               return snprintf(buf, len, "%d.%09u", tmp0, abs(tmp1));
+               tmp0 = (int)div_s64_rem(tmp2, 1000000000, &tmp1);
+               if ((tmp2 < 0) && (tmp0 == 0))
+                       return snprintf(buf, len, "-%d.%09u", tmp0, abs(tmp1));
+               else
+                       return snprintf(buf, len, "%d.%09u", tmp0, abs(tmp1));
        case IIO_VAL_FRACTIONAL_LOG2:
                tmp = shift_right((s64)vals[0] * 1000000000LL, vals[1]);
                tmp0 = (int)div_s64_rem(tmp, 1000000000LL, &tmp1);
--
2.7.4

This email and any attachments are intended for the sole use of the named recipient(s) and contain(s) confidential information that may be proprietary, privileged or copyrighted under applicable law. If you are not the intended recipient, do not read, copy, or forward this email message or any attachments. Delete this email message and any attachments immediately.

^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2020-08-22 10:57 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
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2020-08-20 18:09 [PATCH] iio: Fixed IIO_VAL_FRACTIONAL calcuation for negative values Anand Ashok Dumbre
2020-08-22 10:56 ` Jonathan Cameron
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2020-08-20  8:31 Anand Ashok Dumbre
2020-08-20 13:09 ` Andy Shevchenko

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