linux-kernel - Re: [PATCH 4/5] memstick: rtsx_usb_ms: Support runtime power management

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Thu, 23 Aug 2018 16:12:42 +0800
From:   Kai-Heng Feng <kai.heng.feng@...onical.com>
To:     Ulf Hansson <ulf.hansson@...aro.org>
Cc:     Arnd Bergmann <arnd@...db.de>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Alan Stern <stern@...land.harvard.edu>,
        "Bauer.Chen" <bauer.chen@...ltek.com>, ricky_wu@...ltek.com,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        Linux USB List <linux-usb@...r.kernel.org>
Subject: Re: [PATCH 4/5] memstick: rtsx_usb_ms: Support runtime power
 management

at 21:29, Ulf Hansson <ulf.hansson@...aro.org> wrote:

> [...]
>
>> -#ifdef CONFIG_PM_SLEEP
>> -static int rtsx_usb_ms_suspend(struct device *dev)
>> +#ifdef CONFIG_PM
>> +static int rtsx_usb_ms_runtime_suspend(struct device *dev)
>>  {
>>         struct rtsx_usb_ms *host = dev_get_drvdata(dev);
>>         struct memstick_host *msh = host->msh;
>>
>> -       dev_dbg(ms_dev(host), "--> %s\n", __func__);
>> -
>> +       host->suspend = true;
>>         memstick_suspend_host(msh);
>
> I missed this one. Does this really work? To me, this looks like doing
> things upside-down.
>
> To suspend the host, you first need to runtime resume it, because
> mmc_suspend_host() calls into one of the host ops and my touch the
> device, right?
>
> If you want to suspend the host (actually the naming is wrong, as it's
> about suspending/power-iff the memstick card), that should be done via
> when the memstick core finds that the card is removed or during system
> wide suspend.

Do you mean the logic was wrong even before my modification?

Kai-Heng

>
>> +
>>         return 0;
>>  }
>>
>> -static int rtsx_usb_ms_resume(struct device *dev)
>> +static int rtsx_usb_ms_runtime_resume(struct device *dev)
>>  {
>>         struct rtsx_usb_ms *host = dev_get_drvdata(dev);
>>         struct memstick_host *msh = host->msh;
>>
>> -       dev_dbg(ms_dev(host), "--> %s\n", __func__);
>> -
>>         memstick_resume_host(msh);
>
> According to the above, this seems not correct to me.
>
>> +       host->suspend = false;
>> +       schedule_delayed_work(&host->poll_card, 100);
>> +
>>         return 0;
>>  }
>> -#endif /* CONFIG_PM_SLEEP */
>
> [...]
>
> Kind regards
> Uffe