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- ca.xml
<title>DVB CA Device</title>
<para>The DVB CA device controls the conditional access hardware. It can be accessed through
<emphasis role="tt">/dev/dvb/adapter0/ca0</emphasis>. Data types and and ioctl definitions can be accessed by
including <emphasis role="tt">linux/dvb/ca.h</emphasis> in your application.
</para>
<section id="ca_data_types">
<title>CA Data Types</title>
<section id="ca-slot-info">
<title>ca_slot_info_t</title>
<programlisting>
typedef struct ca_slot_info {
int num; /⋆ slot number ⋆/
int type; /⋆ CA interface this slot supports ⋆/
#define CA_CI 1 /⋆ CI high level interface ⋆/
#define CA_CI_LINK 2 /⋆ CI link layer level interface ⋆/
#define CA_CI_PHYS 4 /⋆ CI physical layer level interface ⋆/
#define CA_DESCR 8 /⋆ built-in descrambler ⋆/
#define CA_SC 128 /⋆ simple smart card interface ⋆/
unsigned int flags;
#define CA_CI_MODULE_PRESENT 1 /⋆ module (or card) inserted ⋆/
#define CA_CI_MODULE_READY 2
} ca_slot_info_t;
</programlisting>
</section>
<section id="ca-descr-info">
<title>ca_descr_info_t</title>
<programlisting>
typedef struct ca_descr_info {
unsigned int num; /⋆ number of available descramblers (keys) ⋆/
unsigned int type; /⋆ type of supported scrambling system ⋆/
#define CA_ECD 1
#define CA_NDS 2
#define CA_DSS 4
} ca_descr_info_t;
</programlisting>
</section>
<section id="ca-caps">
<title>ca_caps_t</title>
<programlisting>
typedef struct ca_caps {
unsigned int slot_num; /⋆ total number of CA card and module slots ⋆/
unsigned int slot_type; /⋆ OR of all supported types ⋆/
unsigned int descr_num; /⋆ total number of descrambler slots (keys) ⋆/
unsigned int descr_type;/⋆ OR of all supported types ⋆/
} ca_cap_t;
</programlisting>
</section>
<section id="ca-msg">
<title>ca_msg_t</title>
<programlisting>
/⋆ a message to/from a CI-CAM ⋆/
typedef struct ca_msg {
unsigned int index;
unsigned int type;
unsigned int length;
unsigned char msg[256];
} ca_msg_t;
</programlisting>
</section>
<section id="ca-descr">
<title>ca_descr_t</title>
<programlisting>
typedef struct ca_descr {
unsigned int index;
unsigned int parity;
unsigned char cw[8];
} ca_descr_t;
</programlisting>
</section>
<section id="ca-pid">
<title>ca-pid</title>
<programlisting>
typedef struct ca_pid {
unsigned int pid;
int index; /⋆ -1 == disable⋆/
} ca_pid_t;
</programlisting>
</section></section>
<section id="ca_function_calls">
<title>CA Function Calls</title>
<section id="ca_fopen">
<title>open()</title>
<para>DESCRIPTION
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
align="char">
<para>This system call opens a named ca device (e.g. /dev/ost/ca) for subsequent use.</para>
<para>When an open() call has succeeded, the device will be ready for use.
The significance of blocking or non-blocking mode is described in the
documentation for functions where there is a difference. It does not affect the
semantics of the open() call itself. A device opened in blocking mode can later
be put into non-blocking mode (and vice versa) using the F_SETFL command
of the fcntl system call. This is a standard system call, documented in the Linux
manual page for fcntl. Only one user can open the CA Device in O_RDWR
mode. All other attempts to open the device in this mode will fail, and an error
code will be returned.</para>
</entry>
</row></tbody></tgroup></informaltable>
<para>SYNOPSIS
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
align="char">
<para>int open(const char ⋆deviceName, int flags);</para>
</entry>
</row></tbody></tgroup></informaltable>
<para>PARAMETERS
</para>
<informaltable><tgroup cols="2"><tbody><row><entry
align="char">
<para>const char
*deviceName</para>
</entry><entry
align="char">
<para>Name of specific video device.</para>
</entry>
</row><row><entry
align="char">
<para>int flags</para>
</entry><entry
align="char">
<para>A bit-wise OR of the following flags:</para>
</entry>
</row><row><entry
align="char">
</entry><entry
align="char">
<para>O_RDONLY read-only access</para>
</entry>
</row><row><entry
align="char">
</entry><entry
align="char">
<para>O_RDWR read/write access</para>
</entry>
</row><row><entry
align="char">
</entry><entry
align="char">
<para>O_NONBLOCK open in non-blocking mode</para>
</entry>
</row><row><entry
align="char">
</entry><entry
align="char">
<para>(blocking mode is the default)</para>
</entry>
</row></tbody></tgroup></informaltable>
<para>RETURN VALUE</para>
<informaltable><tgroup cols="2"><tbody><row><entry
align="char">
<para>ENODEV</para>
</entry><entry
align="char">
<para>Device driver not loaded/available.</para>
</entry>
</row><row><entry
align="char">
<para>EINTERNAL</para>
</entry><entry
align="char">
<para>Internal error.</para>
</entry>
</row><row><entry
align="char">
<para>EBUSY</para>
</entry><entry
align="char">
<para>Device or resource busy.</para>
</entry>
</row><row><entry
align="char">
<para>EINVAL</para>
</entry><entry
align="char">
<para>Invalid argument.</para>
</entry>
</row></tbody></tgroup></informaltable>
</section>
<section id="ca_fclose">
<title>close()</title>
<para>DESCRIPTION
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
align="char">
<para>This system call closes a previously opened audio device.</para>
</entry>
</row></tbody></tgroup></informaltable>
<para>SYNOPSIS
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
align="char">
<para>int close(int fd);</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></tbody></tgroup></informaltable>
<para>RETURN VALUE</para>
<informaltable><tgroup cols="2"><tbody><row><entry
align="char">
<para>EBADF</para>
</entry><entry
align="char">
<para>fd is not a valid open file descriptor.</para>
</entry>
</row></tbody></tgroup></informaltable>
</section>
</section>