docs/designs/gpio-based-cable-presence.md

1 # GPIO-based Cable Presence Detection
5 Created: 2021-07-29
9 The intent of this new daemon design is to report GPIO-based cable presence
18 …intel.com/content/www/us/en/products/docs/servers/ipmi/ipmi-second-gen-interface-spec-v2-rev1-1.ht…
19 2. <https://www.dmtf.org/sites/default/files/Redfish_Cable_Management_Proposal_WIP_04-2021.pdf>
30 Presence states. This new daemon will resIDe in openbmc/dbus-sensors. Its
62 or to turn on base on how phosphor-led-manager is configured. No action is taken
82 new SDR name is cable[0-1]. The SDR name implies that this SDR has the presence
87 cable0-13. One is cable[14-19]. If the object path is not indexed by the user,
94 cdfp[0-3]        | Event-Only        | ns
97 osfp[0-1]        | Event-Only        | ns
107 cdfp[0-3]        | Event-Only        | ns
109 osfp             | Event-Only        | ns
110 osfp[1-2]        | Event-Only        | ns
127 - Explore the option of reporting the presence state via type12 record instead
128   of discrete sensors. The challenge here is that type12 record also has a limit
132 - We could also let the user define how to group different cables from config
136 - Instead of having a sleep-poll mechanism, it is better to have a event
143 - The polling interval is 10 seconds. Is this too long/short for some other
146 - IPMI name string can only be 16 characters. Using square brackets would take
155 - The presence state that is reported by GpioCableSevice is matching the result
158 - Given the SDR name from `ipmitool sdr list event`, say cable[0-1], make sure
163 - Unindex items from the config should have its own SDR ID. For example,
167 - The state of the cable presence need to change with 10 seconds once a cable is