On Mon, Mar 09, 2015 at 03:39:35PM +0000, Jonathan Cameron wrote: > On 25/02/15 15:55, Vianney le Clément de Saint-Marcq wrote: > > Add support for system sleep and runtime power management. > > > > To wake up the device, the SDA line should be held low for at least 33ms > > while SCL is high. As this is not possible using the i2c API (and not > > supported by all i2c adapters), a GPIO connected to the SDA line is > > needed. The GPIO is named "wakeup" and can be specified in a device > > tree with the "wakeup-gpios" binding. > Needs some i2c specialist input on this! As you mentioned it is liable > to be controversial. Wolfram, is this a one off special or do > any other devices do this sort of magic? s/magic/insanity/ :) I have never heard of something like this. Unsuprisingly, I can not recommend doing it this way. But we all know hardware... And while we could think about reusing the bus_recovery_infrastructure, I don't think it is worth the hazzle. So, doing this GPIO fallback may well be the best we can do now.
Attachment:
signature.asc
Description: Digital signature