Public bug reported:

[ Impact ]

 * Systems with Dell DW5826e WWAN modems currently cannot benefit from
USB autosuspend power management, preventing the processor from reaching
deeper PC# states when the modem is idle.

 * Backporting upstream patch [1] that adds rules in
hwdb.d/60-autosuspend.hwdb for Dell DW5826e WWAN modem

[ Test Plan ]

 * DUT: Platform with Dell DW5826e WWAN modem

$ lsusb -d 413c:8217
Bus 004 Device 002: ID 413c:8217 Dell Computer Corp. DW5826e-eSIM Qualcomm 
Snapdragon X12 Global LTE-A
$ cat /sys/bus/usb/devices/4-1/idVendor 
413c
$ cat /sys/bus/usb/devices/4-1/idProduct 
8217

 1. Confirm autosuspend is not enabled before patch and is set to "on"
in power/control

$ cat /sys/bus/usb/devices/4-1/power/control 
on

 2. Install patch
 3. Autosuspend is enabled, namely, set to "auto" in power/control

$ cat power/control
auto

[ Where problems could occur ]

 * The modem might experience connection instability or fail to wake up
properly from suspend.

[ Other Info ]

 * [1] 60-autosuspend.hwdb: Add Dell DW5826e WWAN modem to autosuspend:
https://github.com/systemd/systemd/pull/38685

** Affects: systemd-hwe (Ubuntu)
     Importance: Undecided
         Status: New

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https://bugs.launchpad.net/bugs/2126468

Title:
  Add Dell DW5826e WWAN modem to autosuspend

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