On Fri, 9 Sep 2016, Ritesh Raj Sarraf wrote: > On Fri, 2016-09-09 at 18:44 +0530, Ritesh Raj Sarraf wrote: > > On Fri, 2016-09-09 at 12:54 +0200, Ulf Hansson wrote: > > > This affects the way the core calls the host driver's ->set_ios() > > > callback. Earlier it was invoked first to do power off then power up. > > > With this change it starts with power up instead. > > > I wanted to try this because I suspected the initial state could be wrong. > > > > > > So here are some other ideas on how to move forward. > > > 1. Run with CONFIG_PM unset to see if we can reproduce the problem. > > > 2. Revert back the state in the mmc core we had in 3.16 around how it > > > deals with runtime PM for host devices. That's actually very easy as > > > we only need to remove the pm_runtime_put|get() calls in > > > mmc_claim|release_host(). > > > > > > Ritesh, can you try these options? > > > > > > > Yes. I can try the above ones now. I'm building the kernel for it. > > For #1, menuconfig doesn't allow me to disable CONFIG_PM in 4.8. I checked it > back up till 4.0, and it still doesn't allow disabling CONFIG_PM. You can do it, but it would require some pretty far-reaching changes. Besides, there's really no point. If CONFIG_PM isn't enabled then the kernel doesn't do any runtime PM at all. Alan Stern > For #2, I'm building the 4.8-rc5 kernel with the following change. This build > does not include the previous change you had suggested (related to POWER_CYCLE) > > Date: Fri Sep 9 19:28:03 2016 +0530 > > Disable pm runtime in mmc core > > diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c > index e55cde6..32388d5 100644 > - --- a/drivers/mmc/core/core.c > +++ b/drivers/mmc/core/core.c > @@ -970,9 +970,6 @@ int __mmc_claim_host(struct mmc_host *host, atomic_t *abort) > spin_unlock_irqrestore(&host->lock, flags); > remove_wait_queue(&host->wq, &wait); > > - - if (pm) > - - pm_runtime_get_sync(mmc_dev(host)); > - - > return stop; > } > EXPORT_SYMBOL(__mmc_claim_host); > @@ -1000,7 +997,6 @@ void mmc_release_host(struct mmc_host *host) > spin_unlock_irqrestore(&host->lock, flags); > wake_up(&host->wq); > pm_runtime_mark_last_busy(mmc_dev(host)); > - - pm_runtime_put_autosuspend(mmc_dev(host)); > } > } > EXPORT_SYMBOL(mmc_release_host); -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
