[media] cec: add CEC_CAP_NEEDS_HPD

Add a new capability CEC_CAP_NEEDS_HPD. If this capability is set
then the hardware can only use CEC if the HDMI Hotplug Detect pin
is high. Such hardware cannot handle the corner case in the CEC specification
where it is possible to transmit messages even if no hotplug signal is
present (needed for some displays that turn off the HPD when in standby,
but still have CEC enabled).

Typically hardware that needs this capability have the HPD wired to the CEC
block, often to a 'power' or 'active' pin.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
This commit is contained in:
Hans Verkuil 2017-06-07 11:46:12 -03:00 committed by Mauro Carvalho Chehab
parent 2613cc6fd3
commit f902c1e95d
5 changed files with 22 additions and 7 deletions

View file

@ -336,6 +336,8 @@ static inline int cec_is_unconfigured(__u16 log_addr_mask)
#define CEC_CAP_RC (1 << 4)
/* Hardware can monitor all messages, not just directed and broadcast. */
#define CEC_CAP_MONITOR_ALL (1 << 5)
/* Hardware can use CEC only if the HDMI HPD pin is high. */
#define CEC_CAP_NEEDS_HPD (1 << 6)
/**
* struct cec_caps - CEC capabilities structure.