2.6. ioctls CEC_ADAP_G_LOG_ADDRS and CEC_ADAP_S_LOG_ADDRS

2.6.1. Name

CEC_ADAP_G_LOG_ADDRS, CEC_ADAP_S_LOG_ADDRS - Get or set the logical addresses

2.6.2. Synopsis

CEC_ADAP_G_LOG_ADDRS

int ioctl(int fd, CEC_ADAP_G_LOG_ADDRS, struct cec_log_addrs *argp)

CEC_ADAP_S_LOG_ADDRS

int ioctl(int fd, CEC_ADAP_S_LOG_ADDRS, struct cec_log_addrs *argp)

2.6.3. Arguments

fd
File descriptor returned by open().
argp
Pointer to struct cec_log_addrs.

2.6.4. Description

To query the current CEC logical addresses, applications call ioctl CEC_ADAP_G_LOG_ADDRS with a pointer to a struct cec_log_addrs where the driver stores the logical addresses.

To set new logical addresses, applications fill in struct cec_log_addrs and call ioctl CEC_ADAP_S_LOG_ADDRS with a pointer to this struct. The ioctl CEC_ADAP_S_LOG_ADDRS is only available if CEC_CAP_LOG_ADDRS is set (the ENOTTY error code is returned otherwise). The ioctl CEC_ADAP_S_LOG_ADDRS can only be called by a file descriptor in initiator mode (see ioctls CEC_G_MODE and CEC_S_MODE), if not the EBUSY error code will be returned.

To clear existing logical addresses set num_log_addrs to 0. All other fields will be ignored in that case. The adapter will go to the unconfigured state and the cec_version, vendor_id and osd_name fields are all reset to their default values (CEC version 2.0, no vendor ID and an empty OSD name).

If the physical address is valid (see ioctl CEC_ADAP_S_PHYS_ADDR), then this ioctl will block until all requested logical addresses have been claimed. If the file descriptor is in non-blocking mode then it will not wait for the logical addresses to be claimed, instead it just returns 0.

A CEC_EVENT_STATE_CHANGE event is sent when the logical addresses are claimed or cleared.

Attempting to call ioctl CEC_ADAP_S_LOG_ADDRS when logical address types are already defined will return with error EBUSY.

cec_log_addrs
struct cec_log_addrs
__u8 log_addr[CEC_MAX_LOG_ADDRS] The actual logical addresses that were claimed. This is set by the driver. If no logical address could be claimed, then it is set to CEC_LOG_ADDR_INVALID. If this adapter is Unregistered, then log_addr[0] is set to 0xf and all others to CEC_LOG_ADDR_INVALID.
__u16 log_addr_mask The bitmask of all logical addresses this adapter has claimed. If this adapter is Unregistered then log_addr_mask sets bit 15 and clears all other bits. If this adapter is not configured at all, then log_addr_mask is set to 0. Set by the driver.
__u8 cec_version The CEC version that this adapter shall use. See CEC Versions. Used to implement the CEC_MSG_CEC_VERSION and CEC_MSG_REPORT_FEATURES messages. Note that CEC_OP_CEC_VERSION_1_3A is not allowed by the CEC framework.
__u8 num_log_addrs Number of logical addresses to set up. Must be ≤ available_log_addrs as returned by ioctl CEC_ADAP_G_CAPS. All arrays in this structure are only filled up to index available_log_addrs-1. The remaining array elements will be ignored. Note that the CEC 2.0 standard allows for a maximum of 2 logical addresses, although some hardware has support for more. CEC_MAX_LOG_ADDRS is 4. The driver will return the actual number of logical addresses it could claim, which may be less than what was requested. If this field is set to 0, then the CEC adapter shall clear all claimed logical addresses and all other fields will be ignored.
__u32 vendor_id The vendor ID is a 24-bit number that identifies the specific vendor or entity. Based on this ID vendor specific commands may be defined. If you do not want a vendor ID then set it to CEC_VENDOR_ID_NONE.
__u32 flags Flags. See Flags for struct cec_log_addrs for a list of available flags.
char osd_name[15] The On-Screen Display name as is returned by the CEC_MSG_SET_OSD_NAME message.
__u8 primary_device_type[CEC_MAX_LOG_ADDRS] Primary device type for each logical address. See CEC Primary Device Types for possible types.
__u8 log_addr_type[CEC_MAX_LOG_ADDRS] Logical address types. See CEC Logical Address Types for possible types. The driver will update this with the actual logical address type that it claimed (e.g. it may have to fallback to CEC_LOG_ADDR_TYPE_UNREGISTERED).
__u8 all_device_types[CEC_MAX_LOG_ADDRS] CEC 2.0 specific: the bit mask of all device types. See CEC All Device Types Flags. It is used in the CEC 2.0 CEC_MSG_REPORT_FEATURES message. For CEC 1.4 you can either leave this field to 0, or fill it in according to the CEC 2.0 guidelines to give the CEC framework more information about the device type, even though the framework won’t use it directly in the CEC message.
__u8 features[CEC_MAX_LOG_ADDRS][12] Features for each logical address. It is used in the CEC 2.0 CEC_MSG_REPORT_FEATURES message. The 12 bytes include both the RC Profile and the Device Features. For CEC 1.4 you can either leave this field to all 0, or fill it in according to the CEC 2.0 guidelines to give the CEC framework more information about the device type, even though the framework won’t use it directly in the CEC message.
Flags for struct cec_log_addrs
CEC_LOG_ADDRS_FL_ALLOW_UNREG_FALLBACK 1

By default if no logical address of the requested type can be claimed, then it will go back to the unconfigured state. If this flag is set, then it will fallback to the Unregistered logical address. Note that if the Unregistered logical address was explicitly requested, then this flag has no effect.

CEC_LOG_ADDRS_FL_ALLOW_RC_PASSTHRU 2

By default the CEC_MSG_USER_CONTROL_PRESSED and CEC_MSG_USER_CONTROL_RELEASED messages are only passed on to the follower(s), if any. If this flag is set, then these messages are also passed on to the remote control input subsystem and will appear as keystrokes. This features needs to be enabled explicitly. If CEC is used to enter e.g. passwords, then you may not want to enable this to avoid trivial snooping of the keystrokes.

CEC_LOG_ADDRS_FL_CDC_ONLY 4

If this flag is set, then the device is CDC-Only. CDC-Only CEC devices are CEC devices that can only handle CDC messages.

All other messages are ignored.

CEC Versions
CEC_OP_CEC_VERSION_1_3A 4

CEC version according to the HDMI 1.3a standard.

CEC_OP_CEC_VERSION_1_4B 5

CEC version according to the HDMI 1.4b standard.

CEC_OP_CEC_VERSION_2_0 6

CEC version according to the HDMI 2.0 standard.

CEC Primary Device Types
CEC_OP_PRIM_DEVTYPE_TV 0

Use for a TV.

CEC_OP_PRIM_DEVTYPE_RECORD 1

Use for a recording device.

CEC_OP_PRIM_DEVTYPE_TUNER 3

Use for a device with a tuner.

CEC_OP_PRIM_DEVTYPE_PLAYBACK 4

Use for a playback device.

CEC_OP_PRIM_DEVTYPE_AUDIOSYSTEM 5

Use for an audio system (e.g. an audio/video receiver).

CEC_OP_PRIM_DEVTYPE_SWITCH 6

Use for a CEC switch.

CEC_OP_PRIM_DEVTYPE_VIDEOPROC 7

Use for a video processor device.

CEC Logical Address Types
CEC_LOG_ADDR_TYPE_TV 0

Use for a TV.

CEC_LOG_ADDR_TYPE_RECORD 1

Use for a recording device.

CEC_LOG_ADDR_TYPE_TUNER 2

Use for a tuner device.

CEC_LOG_ADDR_TYPE_PLAYBACK 3

Use for a playback device.

CEC_LOG_ADDR_TYPE_AUDIOSYSTEM 4

Use for an audio system device.

CEC_LOG_ADDR_TYPE_SPECIFIC 5

Use for a second TV or for a video processor device.

CEC_LOG_ADDR_TYPE_UNREGISTERED 6

Use this if you just want to remain unregistered. Used for pure CEC switches or CDC-only devices (CDC: Capability Discovery and Control).

CEC All Device Types Flags
CEC_OP_ALL_DEVTYPE_TV 0x80

This supports the TV type.

CEC_OP_ALL_DEVTYPE_RECORD 0x40

This supports the Recording type.

CEC_OP_ALL_DEVTYPE_TUNER 0x20

This supports the Tuner type.

CEC_OP_ALL_DEVTYPE_PLAYBACK 0x10

This supports the Playback type.

CEC_OP_ALL_DEVTYPE_AUDIOSYSTEM 0x08

This supports the Audio System type.

CEC_OP_ALL_DEVTYPE_SWITCH 0x04

This supports the CEC Switch or Video Processing type.

2.6.5. Return Value

On success 0 is returned, on error -1 and the errno variable is set appropriately. The generic error codes are described at the Generic Error Codes chapter.

The ioctl CEC_ADAP_S_LOG_ADDRS can return the following error codes:

ENOTTY
The CEC_CAP_LOG_ADDRS capability wasn’t set, so this ioctl is not supported.
EBUSY
The CEC adapter is currently configuring itself, or it is already configured and num_log_addrs is non-zero, or another filehandle is in exclusive follower or initiator mode, or the filehandle is in mode CEC_MODE_NO_INITIATOR.
EINVAL
The contents of struct cec_log_addrs is invalid.