tree aa7560f9de6e8ff2e597f76eaa2127c7cb427383
parent 7ce68724414f4c7eb9786379be9bf991e98261e2
author Alpana Kumari <alpankum@in.ibm.com> 1601529490 -0500
committer Santosh Puranik <santosh.puranik@in.ibm.com> 1631628913 +0530

Enable dynamic presence detect of FRUs

This commit enables presence detect of FRUs at runtime.
Anytime any FRU can get attached or de-attached,
this code will detect it and will enable/disable the corresponding
output I2C pin respectively.
Right now we have only one FRU- op-panel, which is attachable or
de-attachable at runtime.

Test- Tested on Simics:
>> 2timers keep running, as part of vpd-manager-
./vpd-manager

keep checking for event occurance...
hasEventOccurred ?
keep checking for event occurance...
hasEventOccurred ?

>> changed signal at presence-pin of FRU2
keep checking for event occurance...
hasEventOccurred ?
keep checking for event occurance...
hasEventOccurred ?
Yes, togggle the gpio            <---------------------event on 2nd timer

>> Again, changed signal at presence-pin of FRU2
keep checking for event occurance...
hasEventOccurred ?
keep checking for event occurance...
hasEventOccurred ?
Yes, togggle the gpio             <---------------------event on 2nd timer

>> changed signal at presence-pin of FRU1
keep checking for event occurance...
hasEventOccurred ?
Yes, togggle the gpio             <---------------------event on 1st timer
keep checking for event occurance...
hasEventOccurred ?

>> Again changed signal at presence-pin of FRU1
keep checking for event occurance...
hasEventOccurred ?
Yes, togggle the gpio             <---------------------event on 1st timer
keep checking for event occurance...
hasEventOccurred ?

>> Noticed change on output gpio after every signal change.
   As of now for testing, output gpio is same for both of these FRUs-

>> Effects on i2c-
 i2cdetect -y 7
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:          -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
20: 20 -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- UU -- -- -- -- -- -- --
50: UU UU UU -- -- -- -- -- -- -- 5a -- -- -- -- --
60: UU UU UU -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- UU --

 i2cdetect -y 7
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:          -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
20: 20 -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- UU -- -- -- -- -- -- --
50: UU 51 UU -- -- -- -- -- -- -- 5a -- -- -- -- --
60: UU UU UU -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- UU --

Also tested for write functionality, shouldn't be affected due to this change
It looks fine.
root@p10bmc:~# busctl introspect  xyz.openbmc_project.Inventory.Manager /xyz/openbmc_project/inventory/system/chassis/motherboard |grep PN
.PN                                                  property  ay        7 48 50 87 71 54 55 56                   emits-change writable

root@p10bmc:~# busctl call com.ibm.VPD.Manager /com/ibm/VPD/Manager com.ibm.VPD.Manager WriteKeyword ossay  "/system/chassis/motherboard" "VINI" "PN" 1 80

root@p10bmc:~# busctl introspect  xyz.openbmc_project.Inventory.Manager /xyz/openbmc_project/inventory/system/chassis/motherboard |grep PN
.PN                                                  property  ay        7 80 50 87 71 54 55 56                   emits-change writable

root@p10bmc:~# busctl call com.ibm.VPD.Manager /com/ibm/VPD/Manager com.ibm.VPD.Manager WriteKeyword ossay  "/system/chassis/motherboard" "VINI" "PN" 1 48

root@p10bmc:~# busctl introspect  xyz.openbmc_project.Inventory.Manager /xyz/openbmc_project/inventory/system/chassis/motherboard |grep PN
.PN                                                  property  ay        7 48 50 87 71 54 55 56                   emits-change writable

Change-Id: If7d311d36bf56ece751afe393a9ba2d83be5df11
Signed-off-by: Alpana Kumari <alpankum@in.ibm.com>