The following issue is for NCS version 1.4.0 and 1.4.1 for an nRF52840 DK target.
When CONFIG_BT_AUTO_PHY_UPDATE=y for both a peripheral and central, I see in Wireshark a LL_PHY_REQ from both sides, as expected. Here’s an example.
As soon as I simply add CONFIG_BT_REMOTE_VERSION=y to the peripheral’s prj.conf, the peripheral no longer sends a LL_PHY_REQ, as shown below.
- Even several seconds (>5 s) after the connection, I don’t see in Wireshark an LL_PHY_REQ from the peripheral.
You should be able to reproduce this issue with the peripheral_uart and central_uart projects by just adding this line to the peripheral uart’s prj.conf: CONFIG_BT_REMOTE_VERSION=y.
The missing LL_PHY_REQ from the peripheral has ramifications such as subsequent user-requested connection parameter updates don’t get sent when using bt_conn_le_param_update().
- The missing le_phy_update_complete() due to the suspected bug prevents resumption of calls to conn.c/conn_auto_initiate() to continue auto-initiated procedures.
- That means slave_update_conn_param() never gets called in conn_auto_initiate(), which prevents the call to k_delayed_work_submit(&conn->update_work, CONN_UPDATE_TIMEOUT),
- The missing "delayed_work" means conn_update_timeout() never runs, preventing auto connection parameter updates and subsequent user-initiated updates.
I haven't verified if this problem occurs with the Zephyr stack instead of the Nordic stack.
