Re: [PATCH v4 1/3] bus: mhi: core: Clear devices when moving execution environments

From: Bhaumik Bhatt
Date: Fri Feb 19 2021 - 14:14:32 EST


On 2021-02-19 08:10 AM, Jeffrey Hugo wrote:
On 2/18/2021 7:17 PM, Bhaumik Bhatt wrote:
When moving from SBL to mission mode execution environment, there
is no remove callback notification to MHI client drivers which
operate on SBL mode only. Client driver devices are being created
in SBL or AMSS(mission mode) and only destroyed after power down
or SYS_ERROR. If there exist any SBL-specific channels, those are
left open and client drivers are thus unaware of the new execution
environment where those channels cannot operate. Close the gap and
issue remove callbacks to SBL-specific client drivers once device
enters mission mode.

Signed-off-by: Bhaumik Bhatt <bbhatt@xxxxxxxxxxxxxx>
---

I like the idea, but I question where this is limited to the
transition to mission mode. Feels like something that should occur on
all EE changes. We might not have a current usecase that is outside
what you've implemented here, but I don't think there is anything
preventing that in future.

You're right. It should not be limited to any single EE transition and that's
how the code is written. I see my commit message gives the impression that it's
only for SBL -> AMSS. I can correct that and mention it to be EE transition
agnostic with SBL to AMSS as the currently usable example.

Thanks,
Bhaumik
---
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project