On Tue, 12 Dec 2006, Brice Goglin wrote: > Hi, > > I know that .../power/state files are deprecated, but I like using them > for basic testing of a driver's suspend/resume routines. Anyway, echoing > something in the .../power/state in current -git does not seem to work > anymore. It does work, but the results depend on the device you want to suspend. For instance, USB devices have no problem at all. PCI devices will ignore your writes because .../power/state can't handle the new multi-stage suspend and resume mechanism. I've been using the patch below to force my tests to work. The fact remains, this way of doing things won't be valid much longer. > For instance, the driver's suspend routine is not called > anymore when writing 3 while it was at least in 2.6.17 and 2.6.18. And > reading the contents of the file afterwards now returns 0 while it > seemed to return 2 before. > > I didn't have time to git-bisect the problem so far, I will if nobody > has any idea. > > And if somebody knows what to use instead of .../power/state to test a > driver's suspend/resume, I'd be happy to hear it too. The explanation in > feature-removal-schedule.txt did not help a lot, neither did the thread > I found on linux-pm :) There is no general-purpose replacement. Probably each bus will end up implementing its own special-purpose sysfs interface for suspend/resume (or not, as the case may be). Alan Stern Index: usb-2.6/drivers/base/power/sysfs.c =================================================================== --- usb-2.6.orig/drivers/base/power/sysfs.c +++ usb-2.6/drivers/base/power/sysfs.c @@ -45,10 +45,6 @@ static ssize_t state_store(struct device pm_message_t state; int error = -EINVAL; - /* disallow incomplete suspend sequences */ - if (dev->bus && (dev->bus->suspend_late || dev->bus->resume_early)) - return error; - state.event = PM_EVENT_SUSPEND; /* Older apps expected to write "3" here - confused with PCI D3 */ if ((n == 1) && !strcmp(buf, "3"))
