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tools:iio:generic_buffer: sign-extend and shift data

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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>
This commit is contained in:
Hartmut Knaack 2015-05-31 14:39:58 +02:00 committed by Jonathan Cameron
parent e83a47cf6a
commit 8e926134ef
1 changed files with 64 additions and 37 deletions
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101
tools/iio/generic_buffer.c
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@ -59,33 +59,80 @@ int size_from_channelarray(struct iio_channel_info *channels, int num_channels)
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 @@ void process_scan(char *data,
&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;