[PATCH] PM: HIBERNATION: add resume_wait param to support MMC-like devices as resume file

[Barry Song]

2011/9/29 Luca Tettamanti <kronos.it at gmail.com>:
> On Thu, Sep 29, 2011 at 5:47 PM, Luca Tettamanti <kronos.it at gmail.com> wrote:
>> 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?
>
> And in case that makes sense, it might be worthwhile to refactor a
> common helper to be also used in do_mounts.c, e.g.
> dev_t wait_for_device(char *name)

it is ok until we have many cases which wait for devices by polling.
but there are only two by the moment.
here i don't see it is worthwhile since the current codes are short
and clear enough.

>
> L

-barry