Hi!
> I found sd card sometimes are damaged/ destroyed > On our devices . > And seems it is caused by kernel's frequently suspend/resume, > Because during suspend/resume, the driver will suspend/resume sdcard > Very frequently, this will damaged the sdcard sometimes, and the damage > is not recoverable .. > > Sometimes kernel will enter suspend and exit suspend very frequently, > Especially when the system is in idle, but some driver is not idle, > And it will wake up the system by irq frequently. > By our power test result, if system enter suspend /resume very frequently, > Will consume more power , because it will enable /disable many devices > During a short time . > > I make a patch to prevent the system to enter suspend/resume state > More than one time during 2 seconds: It is good you managed to diagnose the problem, but this si not the right solution. Either: 1) don't power down SD card during system suspend or maybe even better 2) don't power _up_ SD card during system resume. Let it be powered down until the first access. Thanks, Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/