tools:iio:generic_buffer: sign-extend and shift data
Refactor process_scan() to handle signed and unsigned data, respect shifts
and the data mask for 2, 4 and 8 byte sized scan elements.
Signed-off-by: Hartmut Knaack <knaack.h@gmx.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
diff --git a/tools/iio/generic_buffer.c b/tools/iio/generic_buffer.c
index 419e227..4cd2464 100644
--- a/tools/iio/generic_buffer.c
+++ b/tools/iio/generic_buffer.c
@@ -59,33 +59,80 @@
return bytes;
}
-void print2byte(int input, struct iio_channel_info *info)
+void print2byte(uint16_t input, struct iio_channel_info *info)
{
/* First swap if incorrect endian */
if (info->be)
- input = be16toh((uint16_t)input);
+ input = be16toh(input);
else
- input = le16toh((uint16_t)input);
+ input = le16toh(input);
/*
* Shift before conversion to avoid sign extension
* of left aligned data
*/
input >>= info->shift;
+ input &= info->mask;
if (info->is_signed) {
- int16_t val = input;
-
- val &= (1 << info->bits_used) - 1;
- val = (int16_t)(val << (16 - info->bits_used)) >>
- (16 - info->bits_used);
- printf("%05f ", ((float)val + info->offset)*info->scale);
+ int16_t val = (int16_t)(input << (16 - info->bits_used)) >>
+ (16 - info->bits_used);
+ printf("%05f ", ((float)val + info->offset) * info->scale);
} else {
- uint16_t val = input;
-
- val &= (1 << info->bits_used) - 1;
- printf("%05f ", ((float)val + info->offset)*info->scale);
+ printf("%05f ", ((float)input + info->offset) * info->scale);
}
}
+
+void print4byte(uint32_t input, struct iio_channel_info *info)
+{
+ /* First swap if incorrect endian */
+ if (info->be)
+ input = be32toh(input);
+ else
+ input = le32toh(input);
+
+ /*
+ * Shift before conversion to avoid sign extension
+ * of left aligned data
+ */
+ input >>= info->shift;
+ input &= info->mask;
+ if (info->is_signed) {
+ int32_t val = (int32_t)(input << (32 - info->bits_used)) >>
+ (32 - info->bits_used);
+ printf("%05f ", ((float)val + info->offset) * info->scale);
+ } else {
+ printf("%05f ", ((float)input + info->offset) * info->scale);
+ }
+}
+
+void print8byte(uint64_t input, struct iio_channel_info *info)
+{
+ /* First swap if incorrect endian */
+ if (info->be)
+ input = be64toh(input);
+ else
+ input = le64toh(input);
+
+ /*
+ * Shift before conversion to avoid sign extension
+ * of left aligned data
+ */
+ input >>= info->shift;
+ input &= info->mask;
+ if (info->is_signed) {
+ int64_t val = (int64_t)(input << (64 - info->bits_used)) >>
+ (64 - info->bits_used);
+ /* special case for timestamp */
+ if (info->scale == 1.0f && info->offset == 0.0f)
+ printf("%" PRId64 " ", val);
+ else
+ printf("%05f ",
+ ((float)val + info->offset) * info->scale);
+ } else {
+ printf("%05f ", ((float)input + info->offset) * info->scale);
+ }
+}
+
/**
* process_scan() - print out the values in SI units
* @data: pointer to the start of the scan
@@ -108,32 +155,12 @@
&channels[k]);
break;
case 4:
- if (!channels[k].is_signed) {
- uint32_t val = *(uint32_t *)
- (data + channels[k].location);
- printf("%05f ", ((float)val +
- channels[k].offset)*
- channels[k].scale);
-
- }
+ print4byte(*(uint32_t *)(data + channels[k].location),
+ &channels[k]);
break;
case 8:
- if (channels[k].is_signed) {
- int64_t val = *(int64_t *)
- (data +
- channels[k].location);
- if ((val >> channels[k].bits_used) & 1)
- val = (val & channels[k].mask) |
- ~channels[k].mask;
- /* special case for timestamp */
- if (channels[k].scale == 1.0f &&
- channels[k].offset == 0.0f)
- printf("%" PRId64 " ", val);
- else
- printf("%05f ", ((float)val +
- channels[k].offset)*
- channels[k].scale);
- }
+ print8byte(*(uint64_t *)(data + channels[k].location),
+ &channels[k]);
break;
default:
break;