On 7 January 2013 17:04, Kevin Liu <keyuan.liu@xxxxxxxxx> wrote: > 2013/1/7 Ulf Hansson <ulf.hansson@xxxxxxxxxx>: >> On 7 January 2013 12:16, Kevin Liu <keyuan.liu@xxxxxxxxx> wrote: >>> 2013/1/7 Ulf Hansson <ulf.hansson@xxxxxxxxxx>: >>>> On 21 December 2012 13:59, Kevin Liu <keyuan.liu@xxxxxxxxx> wrote: >>>>> 2012/12/21 Ulf Hansson <ulf.hansson@xxxxxxxxxx>: >>>>>> On 19 December 2012 13:12, Kevin Liu <kliu5@xxxxxxxxxxx> wrote: >>>>>>> If sdio host can wakeup system, its interrupt will _NOT_ be disabled >>>>>>> during suspending. So when card interrupt happens, the sdio irq thread >>>>>>> will be woken up. >>>>>> >>>>>> Is that really needed to handle the irq? >>>>>> >>>>>> I think you should instead wait on the system resume to be handled >>>>>> properly. In the mmc_sdio_resume, sdio_irq thread is woken up to find >>>>>> out if there is an irq to handle. >>>>>> >>>>>> .... >>>>>> if (!err && host->sdio_irqs) >>>>>> wake_up_process(host->sdio_irq_thread); >>>>>> .... >>>>>> >>>>>> Would that not solve your issue? >>>>>> >>>>> >>>>> With current code, if irq keeps on during suspend/resume, when >>>>> interrupt happen, sdio_irq_thread will be woken up and handle the >>>>> interrupt immediately while sdio host has suspended. It won't wait. >>>> >>>> That is because the sdio host, when in a suspended state, does a >>>> mmc_signal_sdio_irq call. Is that really what the host should do in >>>> this state? >>>> >>> >>> Yes, the host should do this because we want the sdio to wakeup host >>> after system suspended. >>> So we must keep interrupt enabled after suspended. >> >> I see that you need to keep the irqs enabled. But that does not mean >> you need to call the mmc_signal_sdio_irq, when the host is in >> suspended. You should only need to keep the irqs enabled to wake up >> the system from suspend, that is enough, the rest could be handled >> through the normal resume sequence. Don't you think? >> > > mmc_signal_sdio_irq is called by sdhci_irq if card interrupt occur. > So if the irqs enabled, then mmc_signal_sdio_irq will be called when > card int from sdio occur even after host suspended and before resumed. > Yes, but is that really correct? Should the host really do mmc_signal_sdio_irq when the host is suspended? To me it feel like a more proper way of dealing with this is to let the normal resume sequence eventually handle it instead? >>> >>>>> >>>>> Just as you said, this patch just let sdio_irq_thread wait untill sdio >>>>> host resume back to handle the interrupt. >>>>> >>>>>>> Claim the host to avoid sdio irq thread handling the pending interrupt >>>>>>> while sdio host suspended. The pending interrupt will be handled after >>>>>>> the host released in resume when sdio host has been resumed. >>>>>>> >>>>>>> Signed-off-by: Jialing Fu <jlfu@xxxxxxxxxxx> >>>>>>> Signed-off-by: Kevin Liu <kliu5@xxxxxxxxxxx> >>>>>>> --- >>>>>>> drivers/mmc/core/sdio.c | 20 ++++++++++++++++++-- >>>>>>> 1 files changed, 18 insertions(+), 2 deletions(-) >>>>>>> >>>>>>> diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c >>>>>>> index 2273ce6..81140b9 100644 >>>>>>> --- a/drivers/mmc/core/sdio.c >>>>>>> +++ b/drivers/mmc/core/sdio.c >>>>>>> @@ -11,6 +11,7 @@ >>>>>>> >>>>>>> #include <linux/err.h> >>>>>>> #include <linux/pm_runtime.h> >>>>>>> +#include <linux/pm_wakeup.h> >>>>>>> >>>>>>> #include <linux/mmc/host.h> >>>>>>> #include <linux/mmc/card.h> >>>>>>> @@ -923,6 +924,17 @@ static int mmc_sdio_suspend(struct mmc_host *host) >>>>>>> mmc_release_host(host); >>>>>>> } >>>>>>> >>>>>>> + /* >>>>>>> + * If sdio host can wakeup system, its interrupt will _NOT_ be disabled >>>>>>> + * during suspending. So the card interrupt may occur after host has >>>>>>> + * suspended. Claim the host here to avoid sdio irq thread handling the >>>>>>> + * pending interrupt while sdio host suspended. The pending interrupt >>>>>>> + * will be handled after the host released in resume when sdio host has >>>>>>> + * been resumed. >>>>>>> + */ >>>>>>> + if (!err && device_may_wakeup(mmc_dev(host))) >>>>>>> + mmc_claim_host(host); >>>>>>> + >>>>>>> return err; >>>>>>> } >>>>>>> >>>>>>> @@ -933,8 +945,12 @@ static int mmc_sdio_resume(struct mmc_host *host) >>>>>>> BUG_ON(!host); >>>>>>> BUG_ON(!host->card); >>>>>>> >>>>>>> - /* Basic card reinitialization. */ >>>>>>> - mmc_claim_host(host); >>>>>>> + /* >>>>>>> + * Basic card reinitialization. >>>>>>> + * if sdio host can wakeup system, the host has been claimed in suspend. >>>>>>> + */ >>>>>>> + if (!device_may_wakeup(mmc_dev(host))) >>>>>>> + mmc_claim_host(host); >>>>>>> >>>>>>> /* No need to reinitialize powered-resumed nonremovable cards */ >>>>>>> if (mmc_card_is_removable(host) || !mmc_card_keep_power(host)) >>>>>>> -- >>>>>>> 1.7.0.4 >>>>>>> >>>>>> >>>>>> Kind regards >>>>>> Ulf Hansson -- 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
