2013/1/7 Ulf Hansson <ulf.hans...@linaro.org>: > On 7 January 2013 12:16, Kevin Liu <keyuan....@gmail.com> wrote: >> 2013/1/7 Ulf Hansson <ulf.hans...@linaro.org>: >>> On 21 December 2012 13:59, Kevin Liu <keyuan....@gmail.com> wrote: >>>> 2012/12/21 Ulf Hansson <ulf.hans...@linaro.org>: >>>>> On 19 December 2012 13:12, Kevin Liu <kl...@marvell.com> 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. >> >>>> >>>> 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 <j...@marvell.com> >>>>>> Signed-off-by: Kevin Liu <kl...@marvell.com> >>>>>> --- >>>>>> 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 majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
