Bluetooth: TBS: Value Changed During Long Read error code

[piotrnarajowski]

Describe the bug
These test cases verify the behavior of the server IUT when we update TBS characteristics with value greater then ATT_MTU-3. We change the value of characteristic (e.g. Bearer Provider Name) with value len greater than ATT_MTU-3. PTS then reads the characteristic value by executing GATT Read Long Characteristic Value with offset set to 0. By the time there is second long read request with a Value Offset of (ATT_MTU-3), we change the value one more time. Zephyr server IUT doesn't respond with Value Changed During Read Long (0x80) error code.

To Reproduce
Can be reproduced with AutoPTS.

Expected behavior
According to TBS spec, section 1.4:

The server shall return an ATT Error Response with the application error code Value Changed During Read Long (0x80) as defined in Table 1.2 to any ATT_READ_BLOB_REQ with a non-zero Value Offset ifthe characteristic value has changed since the last zero offset read response of that characteristic value to that client.

Impact
Failing test cases:
TBS/SR/SPN/BV-05-C
TBS/SR/SPN/BV-06-C
TBS/SR/SPN/BV-07-C
TBS/SR/SPN/BV-08-C
TBS/SR/SPN/BV-09-C
TBS/SR/SPN/BV-10-C
TBS/SR/SPN/BV-11-C
Also same test cases with GTBS prefix

Logs and console output
TBS_SR_SPN_BV_05_C_2024_01_26_17_27_12.zip

Environment (please complete the following information):

• OS: Windows 11
• Toolchain: Zephyr SDK 0.16.4
• bluetooth: tester: Add TBS server tests #68116
• Bluetooth: tbs: change notifications #68367

[Thalley]

@piotrnarajowski how does your PR (#68367) relate to this? Your PR is required to trigger long reads, right? So this can't really be worked on, before your PR has been done (or at least the work should continue on top of your PR), right?

[piotrnarajowski]

@Thalley Yes, PR #68367 is necessary to properly trigger long reads and to reproduce this issue. I'll try, but I'm not sure I will be able to finish it as LE Audio project is coming to an end for me.

[Thalley]

@piotrnarajowski Will your PR ever go out of draft, or will it be abandoned now?

[piotrnarajowski]

@Thalley for now @sjanc will take a look at this, please assign him

[Thalley]

Related to #64175

[github-actions]

This issue has been marked as stale because it has been open (more than) 60 days with no activity. Remove the stale label or add a comment saying that you would like to have the label removed otherwise this issue will automatically be closed in 14 days. Note, that you can always re-open a closed issue at any time.

[github-actions]

This issue has been marked as stale because it has been open (more than) 60 days with no activity. Remove the stale label or add a comment saying that you would like to have the label removed otherwise this issue will automatically be closed in 14 days. Note, that you can always re-open a closed issue at any time.

[github-actions]

This issue has been marked as stale because it has been open (more than) 60 days with no activity. Remove the stale label or add a comment saying that you would like to have the label removed otherwise this issue will automatically be closed in 14 days. Note, that you can always re-open a closed issue at any time.

[github-actions]

This issue has been marked as stale because it has been open (more than) 60 days with no activity. Remove the stale label or add a comment saying that you would like to have the label removed otherwise this issue will automatically be closed in 14 days. Note, that you can always re-open a closed issue at any time.

[Thalley]

@sjanc any plan for this? It's one of the few open bugs we have for LE Audio, so would like to get it closed in the near future

[sjanc]

I'm not sure when I'll have time to look at this

[Thalley]

I'm not sure when I'll have time to look at this

No problem. I'll re-assign to me, and hopefully have a look at in soon

[github-actions]

This issue has been marked as stale because it has been open (more than) 60 days with no activity. Remove the stale label or add a comment saying that you would like to have the label removed otherwise this issue will automatically be closed in 14 days. Note, that you can always re-open a closed issue at any time.