Use polling instead of interrupt for DSP mail box
acknowledgement.
With interrupt method, the amount of time for mail box
acknowledgement can vary, and sometimes long.
This is because interrupt handler reads all interrupt
status registers and masks, which can take long time,
especially on slow I2C bus.
Use polling to directly check for DSP mail box
acknowledgement reduces variability in amount of time
needed, because only 1 register is read.
Cirrus-JIRA-fixed: MMI-912
Change-Id: I21a223bbfdccb3593c61c7d04ae8355f2734c7a9
Signed-off-by: Li Xu <li-xu@outlook.com>
Signed-off-by: Yoon (Seungyoon) Lee <w22905@motorola.com>
Reviewed-on: https://gerrit.mot.com/1259695
SLTApproved: Slta Waiver
SME-Granted: SME Approvals Granted
Tested-by: Jira Key
Reviewed-by: Seungyoon Lee <yoon@motorola.com>
Submit-Approved: Jira Key
Li Xu
b33af28110