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[media] dvb: Document FE_SCALE_DECIBEL units consistently

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In comments and in the documentation, the units of properties marked
with the FE_SCALE_DECIBEL scale are specified in terms of 1/1000 dB
or 0.0001 dB.  This is inconsistent, however, as 1/1000 is 0.001,
not 0.0001.

Note that the v4l-utils divide the value by 1000 for the signal
strength suggesting that the 1/1000 is correct.

Settle on millidecibels, ie. 1/1000dB or 0.001dB.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
This commit is contained in:
David Howells 2015-04-09 16:36:49 -03:00 • committed by Mauro Carvalho Chehab
parent 24d795d361
commit 4c12adad26
2 changed files with 4 additions and 4 deletions
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4
include/uapi/linux/dvb/frontend.h
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@ -467,7 +467,7 @@ struct dtv_cmds_h {
* @FE_SCALE_NOT_AVAILABLE: That QoS measure is not available. That
* could indicate a temporary or a permanent
* condition.
* @FE_SCALE_DECIBEL: The scale is measured in 0.0001 dB steps, typically
* @FE_SCALE_DECIBEL: The scale is measured in 0.001 dB steps, typically
* used on signal measures.
* @FE_SCALE_RELATIVE: The scale is a relative percentual measure,
* ranging from 0 (0%) to 0xffff (100%).
@ -516,7 +516,7 @@ struct dtv_stats {
__u8 scale; /* enum fecap_scale_params type */
union {
__u64 uvalue; /* for counters and relative scales */
__s64 svalue; /* for 0.0001 dB measures */
__s64 svalue; /* for 0.001 dB measures */
};
} __attribute__ ((packed));