| Message ID | 1347517863-30017-1-git-send-email-gururaja.hebbar@ti.com (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Headers | show |
On Thu, Sep 13, 2012 at 12:01 PM, Hebbar, Gururaja <gururaja.hebbar@ti.com> wrote: > From: Vaibhav Bedia <vaibhav.bedia@ti.com> > > In some cases mmc_suspend_host() is not able to claim the > host and proceed with the suspend process. The core returns > -EBUSY to the host controller driver. Unfortunately, the > host controller driver does not pass on this information > to the PM core and hence the system suspend process continues. > > ret = mmc_suspend_host(host->mmc); > if (ret) { > host->suspended = 0; > if (host->pdata->resume) { > ret = host->pdata->resume(dev, host->slot_id); > > The return status from mmc_suspend_host() is overwritten by return > status from host->pdata->resume. So the original return status is lost. > > In these cases the MMC core gets to an unexpected state > during resume and multiple issues related to MMC crop up. > 1. Host controller driver starts accessing the device registers > before the clocks are enabled which leads to a prefetch abort. > 2. A file copy thread which was launched before suspend gets > stuck due to the host not being reclaimed during resume. > > To avoid such problems pass on the -EBUSY status to the PM core > from the host controller driver. With this change, MMC core > suspend might still fail but it does not end up making the > system unusable. Suspend gets aborted and the user can try > suspending the system again. > > Signed-off-by: Vaibhav Bedia <vaibhav.bedia@ti.com> > Signed-off-by: Hebbar, Gururaja <gururaja.hebbar@ti.com> This version is good. Acked-by: Venkatraman S <svenkatr@ti.com> > --- > Changes from V1: > - Instead of forcibly returning -EBUSY on err, retain old > status and pass on the same to the caller. > - add more detail to commit message (explanation with code > snippet) > > :100644 100644 9afdd20... d9af5f1... M drivers/mmc/host/omap_hsmmc.c > drivers/mmc/host/omap_hsmmc.c | 3 +-- > 1 files changed, 1 insertions(+), 2 deletions(-) > > diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c > index 9afdd20..d9af5f1 100644 > --- a/drivers/mmc/host/omap_hsmmc.c > +++ b/drivers/mmc/host/omap_hsmmc.c > @@ -2050,8 +2050,7 @@ static int omap_hsmmc_suspend(struct device *dev) > if (ret) { > host->suspended = 0; > if (host->pdata->resume) { > - ret = host->pdata->resume(dev, host->slot_id); > - if (ret) > + if (host->pdata->resume(dev, host->slot_id)) > dev_dbg(dev, "Unmask interrupt failed\n"); > } > goto err; > -- > 1.7.0.4 > -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi, On Mon, Sep 17 2012, S, Venkatraman wrote: > On Thu, Sep 13, 2012 at 12:01 PM, Hebbar, Gururaja > <gururaja.hebbar@ti.com> wrote: >> From: Vaibhav Bedia <vaibhav.bedia@ti.com> >> >> In some cases mmc_suspend_host() is not able to claim the >> host and proceed with the suspend process. The core returns >> -EBUSY to the host controller driver. Unfortunately, the >> host controller driver does not pass on this information >> to the PM core and hence the system suspend process continues. >> >> ret = mmc_suspend_host(host->mmc); >> if (ret) { >> host->suspended = 0; >> if (host->pdata->resume) { >> ret = host->pdata->resume(dev, host->slot_id); >> >> The return status from mmc_suspend_host() is overwritten by return >> status from host->pdata->resume. So the original return status is lost. >> >> In these cases the MMC core gets to an unexpected state >> during resume and multiple issues related to MMC crop up. >> 1. Host controller driver starts accessing the device registers >> before the clocks are enabled which leads to a prefetch abort. >> 2. A file copy thread which was launched before suspend gets >> stuck due to the host not being reclaimed during resume. >> >> To avoid such problems pass on the -EBUSY status to the PM core >> from the host controller driver. With this change, MMC core >> suspend might still fail but it does not end up making the >> system unusable. Suspend gets aborted and the user can try >> suspending the system again. >> >> Signed-off-by: Vaibhav Bedia <vaibhav.bedia@ti.com> >> Signed-off-by: Hebbar, Gururaja <gururaja.hebbar@ti.com> > > This version is good. > > Acked-by: Venkatraman S <svenkatr@ti.com> Thanks, pushed to mmc-next for 3.7, with a stable@ tag added (right?). - Chris.
diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c index 9afdd20..d9af5f1 100644 --- a/drivers/mmc/host/omap_hsmmc.c +++ b/drivers/mmc/host/omap_hsmmc.c @@ -2050,8 +2050,7 @@ static int omap_hsmmc_suspend(struct device *dev) if (ret) { host->suspended = 0; if (host->pdata->resume) { - ret = host->pdata->resume(dev, host->slot_id); - if (ret) + if (host->pdata->resume(dev, host->slot_id)) dev_dbg(dev, "Unmask interrupt failed\n"); } goto err;