On Mon, 2012-03-19 at 14:35 +0800, Aaron Lu wrote: > Hi, > > On Mon, Mar 19, 2012 at 01:27:00PM +0800, Lin Ming wrote: > > On Mon, 2012-03-19 at 11:36 +0800, Aaron Lu wrote: > > > Hi, > > > > > > On Thu, Mar 01, 2012 at 05:02:54PM +0800, Lin Ming wrote: > > > > ATA port may support runtime D3Cold state, for example, Zero-power ODD case. > > > > This patch adds wakeup notifier and enable/disable run_wake during > > > > supend/resume. > > > > > > I've been thinking this for some time and realized that it would be > > > impossible for AMD's platform to work with this patch, the reason: > > > There is no _PRW in AMD's acpi implementation. And no _PRW would mean > > > the device is not wake up capable in current Linux ACPI implementation. > > > > > > I've checked the ACPI spec and it said: 'the _PRW is only required for > > > devices that have the ability to wake the system from a system sleeping > > > state.' > > > So I'm not sure if _PRW fits here, since the most common use case for > > > zpodd would be: odd put to D3 cold and system is at S0, and odd is back > > > to D0 when necessary without affecting the system sleep state. > > > > > > I suggest we install the acpi pm notifier on the handle based on the > > > following two criteria: > > > 1 This ata device is DA capable; > > > 2 Its acpi device indicates it is able to wake up itself in S0(_S0W > > > evaluates 4). > > > > OK, reasonable to me. > > > > > > > > Does this make sense and will this work for your platform? > > > > Yes. > > > > Great ;-) > > > > > > > Another problem is how to place this ODD device into D3 cold state, > > > since our platform uses _PS3 control method to power off it. Do you have > > > any suggestions? > > > > acpi_bus_set_power will execute _PS3 too. > > > > So I think no problem for AMD's platform. > > > > Sorry I didn't make it clear. > The problem here is, we are going to set the device power state to D3 > cold, and current OSPM has no support for it. > > Another patch of yours solved this problem by defining: > 1 Device supports D3 cold if it has _PR3; > 2 For a device to be put to D3 cold, power off all the power resources > referenced in its _PR3. > > Since this can't work for AMD's platform(there is no _PR3 for the sata > acpi device), I would like to change this a little bit: > 1 Device supports D3 cold if it has _PR3 or _PS3; _PS3 may only mean D3Hot support for other device. You mentioned that AMD platform defined a special device, named ODDZ. How about device supports D3 cold if _PR3 or (is ODDZ and ODDZ._PS3)? > 2 For a device to be put to D3 cold, execute _PS3 first if available and > then deal with _PR3 as above. __acpi_bus_set_power(...) has done this. > > What do you think of this? > If you are OK to the above idea, I can change the corresponding patch for > you to review. OK. Thanks, Lin Ming > > Thanks, > Aaron > > -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
