æ äï2011-03-22 æ 07:06 +0000ïjoeyli(Joey Lee) æåï > Hi Tejun, > > æ äï2011-03-21 æ 18:27 +0100ïTejun Heo æåï > > Hello, > > > > On Mon, Mar 21, 2011 at 12:07:21AM -0600, Joey Lee wrote: > > > Sorry bother you for about support SATA ODD zero power in kernel. > > > > > > Henry didn't reply me. > > > Could you please kindly give any comment for this topic? > > > > > > Looks the SATA ODD zero power didn't have good power reserve number, > > > does that mean support it in Linux kernel is not worthwhile? > > > > Well, 0.1-0.2w is not nothing. It could be meaningful I guess, but > > the concern that I have are... > > > > * How wildly is it gonna be deployed? Most ultraportables don't have > > ODDs to begin with and extra features in ATA land tend to be very > > cumbersome to deploy. It usually ends up like - half of them > > reporting the supportq incorrectly, quarter of them malfunction when > > enabled and so on. > > > > Per my understood, Intel and AMD's are said they support SATA ODD zero > power on newest notebook platform, and currently still have many > notebook ship with ODD. Intel didn't open their spec for support this > new function. > > And, > Yes, this patch didn't test on ultraportables, especially for if they > try to use USB ODD. For this patch We still need have a lot of test. > > > * Why is software involved in this at all? The device needs to > > process the eject button to begin with. I don't really see why ACPI > > or operating system needs to be involved here at all. What prevents > > ODD from implementing it itself? Is there any fundamental reason > > why OS should be involved? > > > > I don't know how does Intel implement this function (by EC or ACPI?), > but AMD customized a ACPI object to provide this function. I will find a > chance to use this function on Windows platform, per hardward guys give > me some information, Windows can resume the ODD power from GUI, I will > try to verify it on Windows platform then reply to this mail. > More information about the SATA ODD zero power support on Windows platform from BIOSer. Unfortunately, I still didn't see the REAL windows system that support SATA ODD zero power. Per discuss with BIOSer, they said: - The ODD icon still show up when ODD power-off. + Driver turn-off ODD power if there have no disk in tray. - End user can power-on ODD by click ODD icon on GUI. + Driver evaluate ACPI method to power-on ODD. - Intel and AMD all use ACPI to implement interactive with Windows. Until now, Intel still didn't open any spec for ODD, as I know, there also didn't have many shipped notebook support it. Thank's a lot! Joey Lee > > The thing is that if it isn't essential, people aren't gonna > > implement it anyway and we just end up with unused code. > > > > Thanks. > > > > Yes, this is not a essential feature, just Intel and AMD all said they > support it and some ODM also want to implement. > > > Thank's a lot! > Joey Lee > -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
