You are right. I just verify the I2C runtime suspend/resume without this patch. It works well.
Thanks, Bin -----Original Message----- From: Tardy, Pierre Sent: Wednesday, November 24, 2010 6:36 PM To: Yang, Bin; [email protected] Cc: [email protected] Subject: RE: [Meego-kernel] [PATCH 5/5] tc35894xbg: add runtime pm support Bin Yang, > This patch add keypad runtime pm support. > As a keypad driver, it will never go to power down mode. HW will goto power > saving mode > when there is no key pressed. So the runtime pm callback functions do nothing. If you dont do anything special for runtime_pm, there is no need to implement runtime_pm in your driver. This is just consuming cpu cycles, and code size for nothing. A child with runtime_pm disabled (the default for a non runtime_pm supporting driver) will not prevent his parent to correctly go runtime_suspend. The only reason you would like to implement runtime_pm is to do more high level get() and set(), that would prevent thrashing of the parent. (e.g keep the parent active when there is a sequence of i2c transfer known by the child) You don't have any put and get in your patch, so your driver will show suspended all the time. Regards, Pierre _______________________________________________ MeeGo-kernel mailing list [email protected] http://lists.meego.com/listinfo/meego-kernel
