FS#11065 - Disable line out for iPod Video

Attached to Project: Rockbox
Opened by Andree Buschmann (Buschel) - Saturday, 27 February 2010, 19:52 GMT
Last edited by Andree Buschmann (Buschel) - Saturday, 20 March 2010, 15:02 GMT
Task Type Patches
Category Drivers
Status Closed
Assigned To No-one
Operating System iPod 5G
Severity Low
Priority Normal
Reported Version Release 3.4
Due in Version Undecided
Due Date Undecided
Percent Complete 100%
Votes 0
Private No


The lineout of the iPod Video consumes 0.5-0.6 mA even if there is no sink connected. To save some power and reach longer battery runtime it is reasonable to implement an option to be able to switch off the lineout. The battery lifetime is ~30 minutes longer with this setting.

This patch combines the lineout on/off with the accessory voltage supply. Switching off the accessory supply will also switch off the lineout. As this combination might mix up different things and usecases -- e.g. using lineout without any accessory device but simple adaptor -- I would prefer to introduce a new system setting.
This task depends upon

Closed by  Andree Buschmann (Buschel)
Saturday, 20 March 2010, 15:02 GMT
Reason for closing:  Accepted
Additional comments about closing:  Submitted with r25257.
Comment by MichaelGiacomelli (saratoga) - Saturday, 27 February 2010, 20:56 GMT
Isn't there a GPIO pin or similar that can be used to detect a line out accessory? I might be confusing it with the Sansas, but I though docks short two pins together to enable line out.
Comment by Andree Buschmann (Buschel) - Sunday, 28 February 2010, 15:49 GMT
I have played around with some adaptors and did not find any way to detect a connected accessory. Additionally I have used a self-made adaptor to perform some measurements. Those measurements showed that a) Apple FW had accessory supply enabled always b) Apple FW had the lineouts active all the time.

My question in the first post should not open new discussions about the accessory detection -- this has been done and (for now to me) there is no way knwon for automatic detection. My question was if it is acceptable to create a new setting or if I shall implement the lineout-disabling as done in this patch. This way any user who is using his iPod's lineout on a dock connector / adaptor, that does not need power supply via the iPod, will loose battery runtime as he must enable the accessory power supply.
Comment by Andree Buschmann (Buschel) - Saturday, 20 March 2010, 14:49 GMT
This new patch introduces the new system setting "Line-out".