Hi Sudeep and Daniel: Thanks your response. My CPU is arm CA7 that is 32bits cpu. If I directly used cpuidle-arm.c function with enable "Generic ARM/ARM64 CPU idle Driver", the cpuidle driver mount fail with "unsupported enable-method property". This is due to linux kernel no invoke CPUIDLE_METHOD_OF_DECLARE for arm 32bits cpu. There have no define cpuidle_ops.init and cpuidle_ops.suspend function for arm 32bits cpu too. So I create cpuidle-sunplus.c to execute my cpuidle function. Please correct me if I got mistake. 邱垂峰 EdwinChiu 智能運算專案 T: +886-3-5786005 ext.2590 edwin.chiu@xxxxxxxxxxx 300 新竹科學園區創新一路19號 > -----Original Message----- > From: Sudeep Holla <sudeep.holla@xxxxxxx> > Sent: Monday, December 20, 2021 8:11 PM > To: Edwin Chiu <edwinchiu0505tw@xxxxxxxxx> > Cc: robh+dt@xxxxxxxxxx; Edwin Chiu 邱垂峰 <edwin.chiu@xxxxxxxxxxx>; devicetree@xxxxxxxxxxxxxxx; > linux-kernel@xxxxxxxxxxxxxxx; rafael@xxxxxxxxxx; Sudeep Holla <sudeep.holla@xxxxxxx>; > daniel.lezcano@xxxxxxxxxx; linux-pm@xxxxxxxxxxxxxxx > Subject: Re: [PATCH v2 2/2] cpuidle:sunplus:create cpuidle driver for sunplus sp7021 > > On Mon, Dec 20, 2021 at 01:37:32PM +0800, Edwin Chiu wrote: > > Create cpuidle driver for sunplus sp7021 chip > > > > Based on the driver here, I couldn't understand why you can't make use of existing cpuidle-arm.c driver > > -- > Regards, > Sudeep
