Am 07.03.21 um 16:52 schrieb Alan Stern:

On Sun, Mar 07, 2021 at 06:58:10AM +0100, Matthias Schwarzott wrote:

quoted

Am 05.03.21 um 20:14 schrieb Alan Stern:

quoted

Is runtime power management enabled?  Maybe the Kindle disconnects
whenever the computer tries to suspend it.  This typically happens 2
seconds after the last command was issued, which matches your
observations.  If runtime PM is enabled, you can try disabling it.

I assume this means autosuspend is not used:

# cat /sys/block/sde/device/power/control
on

This means autosuspend isn't used for the sde drive.  But the log
extract above shows that the Kindle is sdc, not sde.

Yes, confusing. From different boots with another usb disc not detected.

This time Kindle is sde again:

# dmesg |tail
[83709.973141] usb-storage 3-4:1.0: USB Mass Storage device detected
[83709.973226] scsi host8: usb-storage 3-4:1.0
[83711.028665] scsi 8:0:0:0: Direct-Access     Kindle   Internal Storage 
0100 PQ: 0 ANSI: 2
[83711.028792] sd 8:0:0:0: Attached scsi generic sg5 type 0
[83711.031536] sd 8:0:0:0: Power-on or device reset occurred
[83711.046604] sd 8:0:0:0: [sde] Attached SCSI removable disk
[83713.145467] sd 8:0:0:0: [sde] 6688768 512-byte logical blocks: (3.42 
GB/3.19 GiB)
[83713.364900] sd 8:0:0:0: [sde] Write cache: enabled, read cache: 
enabled, doesn't support DPO or FUA
[83713.364906] sde: detected capacity change from 0 to 6688768
[83713.368036]  sde: sde1
# cat /sys/block/sde/device/power/control
on

power/control reports the same value for all sd? devices on this system.

Matthias