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DocBook/dvb: Improve description of the DVB API v5 

Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@redhat.com>
parent 5a0deeed
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Documentation/DocBook/dvb/dvbapi.xml
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......@@ -34,6 +34,14 @@
<revhistory>
<!-- Put document revisions here, newest first. -->
<revision>
<revnumber>2.0.4</revnumber>
<date>2011-05-06</date>
<authorinitials>mcc</authorinitials>
<revremark>
Add more information about DVB APIv5, better describing the frontend GET/SET props ioctl's.
</revremark>
</revision>
<revision>
<revnumber>2.0.3</revnumber>
<date>2010-07-03</date>
......
Documentation/DocBook/dvb/dvbproperty.xml
View file @ 0ed08b49
<section id="FE_GET_PROPERTY">
<section id="FE_GET_SET_PROPERTY">
<title>FE_GET_PROPERTY/FE_SET_PROPERTY</title>
<programlisting>
/* Reserved fields should be set to 0 */
struct dtv_property {
__u32 cmd;
union {
__u32 data;
struct {
__u8 data[32];
__u32 len;
__u32 reserved1[3];
void *reserved2;
} buffer;
} u;
int result;
} __attribute__ ((packed));
/* num of properties cannot exceed DTV_IOCTL_MAX_MSGS per ioctl */
#define DTV_IOCTL_MAX_MSGS 64
struct dtv_properties {
__u32 num;
struct dtv_property *props;
};
</programlisting>
<section id="FE_GET_PROPERTY">
<title>FE_GET_PROPERTY</title>
<para>DESCRIPTION
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
align="char">
<para>This ioctl call returns one or more frontend properties. This call only
requires read-only access to the device.</para>
</entry>
</row></tbody></tgroup></informaltable>
<para>SYNOPSIS
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
align="char">
<para>int ioctl(int fd, int request = <link linkend="FE_GET_PROPERTY">FE_GET_PROPERTY</link>,
dtv_properties &#x22C6;props);</para>
</entry>
</row></tbody></tgroup></informaltable>
<para>PARAMETERS
</para>
<informaltable><tgroup cols="2"><tbody><row><entry align="char">
<para>int fd</para>
</entry><entry
align="char">
<para>File descriptor returned by a previous call to open().</para>
</entry>
</row><row><entry
align="char">
<para>int num</para>
</entry><entry
align="char">
<para>Equals <link linkend="FE_GET_PROPERTY">FE_GET_PROPERTY</link> for this command.</para>
</entry>
</row><row><entry
align="char">
<para>struct dtv_property *props</para>
</entry><entry
align="char">
<para>Points to the location where the front-end property commands are stored.</para>
</entry>
</row></tbody></tgroup></informaltable>
<para>ERRORS</para>
<informaltable><tgroup cols="2"><tbody><row>
<entry align="char"><para>EINVAL</para></entry>
<entry align="char"><para>Invalid parameter(s) received or number of parameters out of the range.</para></entry>
</row><row>
<entry align="char"><para>ENOMEM</para></entry>
<entry align="char"><para>Out of memory.</para></entry>
</row><row>
<entry align="char"><para>EFAULT</para></entry>
<entry align="char"><para>Failure while copying data from/to userspace.</para></entry>
</row><row>
<entry align="char"><para>EOPNOTSUPP</para></entry>
<entry align="char"><para>Property type not supported.</para></entry>
</row></tbody></tgroup></informaltable>
</section>
<section id="FE_SET_PROPERTY">
<title>FE_SET_PROPERTY</title>
<para>DESCRIPTION
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
align="char">
<para>This ioctl call sets one or more frontend properties. This call only
requires read-only access to the device.</para>
</entry>
</row></tbody></tgroup></informaltable>
<para>SYNOPSIS
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
align="char">
<para>int ioctl(int fd, int request = <link linkend="FE_SET_PROPERTY">FE_SET_PROPERTY</link>,
dtv_properties &#x22C6;props);</para>
</entry>
</row></tbody></tgroup></informaltable>
<para>PARAMETERS
</para>
<informaltable><tgroup cols="2"><tbody><row><entry align="char">
<para>int fd</para>
</entry><entry
align="char">
<para>File descriptor returned by a previous call to open().</para>
</entry>
</row><row><entry
align="char">
<para>int num</para>
</entry><entry
align="char">
<para>Equals <link linkend="FE_SET_PROPERTY">FE_SET_PROPERTY</link> for this command.</para>
</entry>
</row><row><entry
align="char">
<para>struct dtv_property *props</para>
</entry><entry
align="char">
<para>Points to the location where the front-end property commands are stored.</para>
</entry>
</row></tbody></tgroup></informaltable>
<para>ERRORS
</para>
<informaltable><tgroup cols="2"><tbody><row>
<entry align="char"><para>EINVAL</para></entry>
<entry align="char"><para>Invalid parameter(s) received or number of parameters out of the range.</para></entry>
</row><row>
<entry align="char"><para>ENOMEM</para></entry>
<entry align="char"><para>Out of memory.</para></entry>
</row><row>
<entry align="char"><para>EFAULT</para></entry>
<entry align="char"><para>Failure while copying data from/to userspace.</para></entry>
</row><row>
<entry align="char"><para>EOPNOTSUPP</para></entry>
<entry align="char"><para>Property type not supported.</para></entry>
</row></tbody></tgroup></informaltable>
</section>
<para>
On <link linkend="FE_GET_PROPERTY">FE_GET_PROPERTY</link>/<link linkend="FE_SET_PROPERTY">FE_SET_PROPERTY</link>,
the actual action is determined by the dtv_property cmd/data pairs. With one single ioctl, is possible to
get/set up to 64 properties. The actual meaning of each property is described on the next sections.
</para>
<para>The Available frontend property types are:</para>
<programlisting>
#define DTV_UNDEFINED 0
#define DTV_TUNE 1
#define DTV_CLEAR 2
#define DTV_FREQUENCY 3
#define DTV_MODULATION 4
#define DTV_BANDWIDTH_HZ 5
#define DTV_INVERSION 6
#define DTV_DISEQC_MASTER 7
#define DTV_SYMBOL_RATE 8
#define DTV_INNER_FEC 9
#define DTV_VOLTAGE 10
#define DTV_TONE 11
#define DTV_PILOT 12
#define DTV_ROLLOFF 13
#define DTV_DISEQC_SLAVE_REPLY 14
#define DTV_FE_CAPABILITY_COUNT 15
#define DTV_FE_CAPABILITY 16
#define DTV_DELIVERY_SYSTEM 17
#define DTV_ISDBT_PARTIAL_RECEPTION 18
#define DTV_ISDBT_SOUND_BROADCASTING 19
#define DTV_ISDBT_SB_SUBCHANNEL_ID 20
#define DTV_ISDBT_SB_SEGMENT_IDX 21
#define DTV_ISDBT_SB_SEGMENT_COUNT 22
#define DTV_ISDBT_LAYERA_FEC 23
#define DTV_ISDBT_LAYERA_MODULATION 24
#define DTV_ISDBT_LAYERA_SEGMENT_COUNT 25
#define DTV_ISDBT_LAYERA_TIME_INTERLEAVING 26
#define DTV_ISDBT_LAYERB_FEC 27
#define DTV_ISDBT_LAYERB_MODULATION 28
#define DTV_ISDBT_LAYERB_SEGMENT_COUNT 29
#define DTV_ISDBT_LAYERB_TIME_INTERLEAVING 30
#define DTV_ISDBT_LAYERC_FEC 31
#define DTV_ISDBT_LAYERC_MODULATION 32
#define DTV_ISDBT_LAYERC_SEGMENT_COUNT 33
#define DTV_ISDBT_LAYERC_TIME_INTERLEAVING 34
#define DTV_API_VERSION 35
#define DTV_CODE_RATE_HP 36
#define DTV_CODE_RATE_LP 37
#define DTV_GUARD_INTERVAL 38
#define DTV_TRANSMISSION_MODE 39
#define DTV_HIERARCHY 40
#define DTV_ISDBT_LAYER_ENABLED 41
#define DTV_ISDBS_TS_ID 42
</programlisting>
<section id="fe_property_common">
<title>Parameters that are common to all Digital TV standards</title>
<section id="DTV_FREQUENCY">
<title><constant>DTV_FREQUENCY</constant></title>
<para>Central frequency of the channel, in HZ.</para>
<para>Notes:</para>
<para>1)For ISDB-T, the channels are usually transmitted with an offset of 143kHz.
E.g. a valid frequncy could be 474143 kHz. The stepping is bound to the bandwidth of
the channel which is 6MHz.</para>
<para>2)As in ISDB-Tsb the channel consists of only one or three segments the
frequency step is 429kHz, 3*429 respectively. As for ISDB-T the
central frequency of the channel is expected.</para>
</section>
<section id="DTV_BANDWIDTH_HZ">
<title><constant>DTV_BANDWIDTH_HZ</constant></title>
<para>Bandwidth for the channel, in HZ.</para>
<para>Possible values:
<constant>6000000</constant>,
<constant>7000000</constant>,
<constant>8000000</constant>.
</para>
<para>Notes:</para>
<para>1) For ISDB-T it should be always 6000000Hz (6MHz)</para>
<para>2) For ISDB-Tsb it can vary depending on the number of connected segments</para>
<para>3) Bandwidth doesn't apply for DVB-C transmissions, as the bandwidth
for DVB-C depends on the symbol rate</para>
<para>4) Bandwidth in ISDB-T is fixed (6MHz) or can be easily derived from
other parameters (DTV_ISDBT_SB_SEGMENT_IDX,
DTV_ISDBT_SB_SEGMENT_COUNT).</para>
</section>
<section id="DTV_DELIVERY_SYSTEM">
<title><constant>DTV_DELIVERY_SYSTEM</constant></title>
<para>Specifies the type of Delivery system</para>
<para>Possible values: </para>
<programlisting>
typedef enum fe_delivery_system {
SYS_UNDEFINED,
SYS_DVBC_ANNEX_AC,
SYS_DVBC_ANNEX_B,
SYS_DVBT,
SYS_DSS,
SYS_DVBS,
SYS_DVBS2,
SYS_DVBH,
SYS_ISDBT,
SYS_ISDBS,
SYS_ISDBC,
SYS_ATSC,
SYS_ATSCMH,
SYS_DMBTH,
SYS_CMMB,
SYS_DAB,
} fe_delivery_system_t;
</programlisting>
</section>
<section id="DTV_TRANSMISSION_MODE">
<title><constant>DTV_TRANSMISSION_MODE</constant></title>
<para>Specifies the number of carriers used by the standard</para>
<para>Possible values are:</para>
<programlisting>
typedef enum fe_transmit_mode {
TRANSMISSION_MODE_2K,
TRANSMISSION_MODE_8K,
TRANSMISSION_MODE_AUTO,
TRANSMISSION_MODE_4K
} fe_transmit_mode_t;
</programlisting>
<para>Notes:</para>
<para>1) ISDB-T supports three carrier/symbol-size: 8K, 4K, 2K. It is called
'mode' in the standard: Mode 1 is 2K, mode 2 is 4K, mode 3 is 8K</para>
<para>2) If <constant>DTV_TRANSMISSION_MODE</constant> is set the <constant>TRANSMISSION_MODE_AUTO</constant> the
hardware will try to find the correct FFT-size (if capable) and will
use TMCC to fill in the missing parameters.</para>
</section>
<section id="DTV_GUARD_INTERVAL">
<title><constant>DTV_GUARD_INTERVAL</constant></title>
<para>Possible values are:</para>
<programlisting>
typedef enum fe_guard_interval {
GUARD_INTERVAL_1_32,
GUARD_INTERVAL_1_16,
GUARD_INTERVAL_1_8,
GUARD_INTERVAL_1_4,
GUARD_INTERVAL_AUTO
} fe_guard_interval_t;
</programlisting>
<para>Notes:</para>
<para>1) If <constant>DTV_GUARD_INTERVAL</constant> is set the <constant>GUARD_INTERVAL_AUTO</constant> the hardware will
try to find the correct guard interval (if capable) and will use TMCC to fill
in the missing parameters.</para>
</section>
</section>
<section id="isdbt">
<title>ISDB-T frontend</title>
<para>This section describes shortly what are the possible parameters in the Linux
......@@ -32,73 +338,6 @@
<para>Parameters used by ISDB-T and ISDB-Tsb.</para>
<section id="isdbt-parms">
<title>Parameters that are common with DVB-T and ATSC</title>
<section id="isdbt-freq">
<title><constant>DTV_FREQUENCY</constant></title>
<para>Central frequency of the channel.</para>
<para>For ISDB-T the channels are usually transmitted with an offset of 143kHz. E.g. a
valid frequncy could be 474143 kHz. The stepping is bound to the bandwidth of
the channel which is 6MHz.</para>
<para>As in ISDB-Tsb the channel consists of only one or three segments the
frequency step is 429kHz, 3*429 respectively. As for ISDB-T the
central frequency of the channel is expected.</para>
</section>
<section id="isdbt-bw">
<title><constant>DTV_BANDWIDTH_HZ</constant> (optional)</title>
<para>Possible values:</para>
<para>For ISDB-T it should be always 6000000Hz (6MHz)</para>
<para>For ISDB-Tsb it can vary depending on the number of connected segments</para>
<para>Note: Hardware specific values might be given here, but standard
applications should not bother to set a value to this field as
standard demods are ignoring it anyway.</para>
<para>Bandwidth in ISDB-T is fixed (6MHz) or can be easily derived from
other parameters (DTV_ISDBT_SB_SEGMENT_IDX,
DTV_ISDBT_SB_SEGMENT_COUNT).</para>
</section>
<section id="isdbt-delivery-sys">
<title><constant>DTV_DELIVERY_SYSTEM</constant></title>
<para>Possible values: <constant>SYS_ISDBT</constant></para>
</section>
<section id="isdbt-tx-mode">
<title><constant>DTV_TRANSMISSION_MODE</constant></title>
<para>ISDB-T supports three carrier/symbol-size: 8K, 4K, 2K. It is called
'mode' in the standard: Mode 1 is 2K, mode 2 is 4K, mode 3 is 8K</para>
<para>Possible values: <constant>TRANSMISSION_MODE_2K</constant>, <constant>TRANSMISSION_MODE_8K</constant>,
<constant>TRANSMISSION_MODE_AUTO</constant>, <constant>TRANSMISSION_MODE_4K</constant></para>
<para>If <constant>DTV_TRANSMISSION_MODE</constant> is set the <constant>TRANSMISSION_MODE_AUTO</constant> the
hardware will try to find the correct FFT-size (if capable) and will
use TMCC to fill in the missing parameters.</para>
<para><constant>TRANSMISSION_MODE_4K</constant> is added at the same time as the other new parameters.</para>
</section>
<section id="isdbt-guard-interval">
<title><constant>DTV_GUARD_INTERVAL</constant></title>
<para>Possible values: <constant>GUARD_INTERVAL_1_32</constant>, <constant>GUARD_INTERVAL_1_16</constant>, <constant>GUARD_INTERVAL_1_8</constant>,
<constant>GUARD_INTERVAL_1_4</constant>, <constant>GUARD_INTERVAL_AUTO</constant></para>
<para>If <constant>DTV_GUARD_INTERVAL</constant> is set the <constant>GUARD_INTERVAL_AUTO</constant> the hardware will
try to find the correct guard interval (if capable) and will use TMCC to fill
in the missing parameters.</para>
</section>
</section>
<section id="isdbt-new-parms">
<title>ISDB-T only parameters</title>
......
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