[PATCH] PM: HIBERNATION: add resume_wait param to support MMC-like devices as resume file
pavel at ucw.cz
Thu Oct 6 13:58:18 EDT 2011
> 2011/9/29 Luca Tettamanti <kronos.it at gmail.com>:
> > On Thu, Sep 29, 2011 at 11:29 AM, Barry Song <Barry.Song at csr.com> wrote:
> >> From: Barry Song <baohua.song at csr.com>
> >> Some devices like mmc are async detected very slow. For example,
> >> drivers/mmc/host/sdhci.c launchs a 200ms delayed work to detect
> >> mmc partitions then add disk.
> >> we do have wait_for_device_probe and scsi_complete_async_scans
> >> before calling swsusp_check, but it is not enough to wait mmc.
> >> This patch adds resumewait kernel param just like rootwait so
> >> that we have enough time to wait mmc ready. The differene is
> >> here we wait for resume partition but rootwait waits for rootfs
> >> partition.
> > I assume that such a device would need "rootwait" to boot in the first
> > place; why don't you "overload" the param to also enable waiting in
> > the resume path?
> not real. for an embedded product, the type of the rootfs, the place
> of the rootfs and the way to mount rootfs are pretty flexible.
> even though both rootfs and resume file use mmc, they will be in
> different partitions at least. so i don't think rootwait can overload
It would be good to at least model it the same way. rootdelay allows
you to specify time, which is important for USB devices...
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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