Re: MMC runtime PM patches break libertas probe

[Arnd Hannemann <arnd@arndnet.de>]

Am 16.11.2010 21:58, schrieb Ohad Ben-Cohen:
> On Tue, Nov 16, 2010 at 7:17 PM, Arnd Hannemann
> <hannemann@nets.rwth-aachen.de> >> > Its an AP4 (SH7372) evaluation
> board from renesas. It has an SD-Slot,
>   
>> where you plug the SDIO card into it. No special wiring or something
>> like this. So I doubt some external GPIOs are involved.
>> I have no idea how the wifi card gets its power, but I hope its over
>> some well defined pins within the SD slot...
>>     
> Can you please specify what was the wlan card you used ? is it a
> commercial card or an evaluation board of some sort ?
>   
It says: c-guys sd link11b driver is b43.
It's an commercial card.

> You said it, but just to be sure - I assume there is no external power
> supply involved with that card, right ? it's just plugged into the SD
> slot with no extra wire whatsoever ?
>   
Yes, just plugged it in. No extra wire whatsover.

Regards,
Arnd

> Thanks!
> Ohad.
>
>   
>> I was able to work with 2.6.35 and .36 plus some out-of-tree patches
>> for the sh_mobile_sdhi mfd, which are now in mainline:
>> mmc: Allow 2 byte requests in 4-bit mode for tmio_mmc
>> tmio_mmc: don't clear unhandled pending interrupts
>> tmio_mmc: don't clear unhandled pending interrupts
>>
>>     
>>>> From 6b5691bdd8184cc0876d209c69d38844ea10f678 Mon Sep 17 00:00:00 2001
>>>> From: Ohad Ben-Cohen <ohad@wizery.com>
>>>> Date: Mon, 1 Nov 2010 09:41:44 +0200
>>>> Subject: [PATCH] mmc: add MMC_CAP_RUNTIME_PM
>>>>
>>>> Some board/card/host configurations are not capable of powering off/on
>>>> on the card during runtime.
>>>>
>>>> To support such configurations, and to allow smoother transition to
>>>> runtime PM behavior, MMC_CAP_RUNTIME_PM is added, so hosts need to
>>>> explicitly indicate that it's OK to power off their cards after boot.
>>>>
>>>> This will prevent sdio_bus_probe() from failing to power on the card
>>>> when the driver is loaded on such setups.
>>>>
>>>> Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
>>>> ---
>>>>  drivers/mmc/core/sdio.c     |   37 +++++++++++++++++++++++--------------
>>>>  drivers/mmc/core/sdio_bus.c |   33 ++++++++++++++++++++++-----------
>>>>  include/linux/mmc/host.h    |    1 +
>>>>  3 files changed, 46 insertions(+), 25 deletions(-)
>>>>
>>>> diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c
>>>> index 6a9ad40..373d56d 100644
>>>> --- a/drivers/mmc/core/sdio.c
>>>> +++ b/drivers/mmc/core/sdio.c
>>>> @@ -547,9 +547,11 @@ static void mmc_sdio_detect(struct mmc_host *host)
>>>>        BUG_ON(!host->card);
>>>>
>>>>        /* Make sure card is powered before detecting it */
>>>> -       err = pm_runtime_get_sync(&host->card->dev);
>>>> -       if (err < 0)
>>>> -               goto out;
>>>> +       if (host->caps & MMC_CAP_RUNTIME_PM) {
>>>> +               err = pm_runtime_get_sync(&host->card->dev);
>>>> +               if (err < 0)
>>>> +                       goto out;
>>>> +       }
>>>>
>>>>        mmc_claim_host(host);
>>>>
>>>> @@ -570,7 +572,8 @@ out:
>>>>        }
>>>>
>>>>        /* Tell PM core that we're done */
>>>> -       pm_runtime_put(&host->card->dev);
>>>> +       if (host->caps & MMC_CAP_RUNTIME_PM)
>>>> +               pm_runtime_put(&host->card->dev);
>>>>  }
>>>>
>>>>  /*
>>>> @@ -720,16 +723,21 @@ int mmc_attach_sdio(struct mmc_host *host, u32 ocr)
>>>>        card = host->card;
>>>>
>>>>        /*
>>>> -        * Let runtime PM core know our card is active
>>>> +        * Enable runtime PM only if supported by host+card+board
>>>>         */
>>>> -       err = pm_runtime_set_active(&card->dev);
>>>> -       if (err)
>>>> -               goto remove;
>>>> +       if (host->caps & MMC_CAP_RUNTIME_PM) {
>>>> +               /*
>>>> +                * Let runtime PM core know our card is active
>>>> +                */
>>>> +               err = pm_runtime_set_active(&card->dev);
>>>> +               if (err)
>>>> +                       goto remove;
>>>>
>>>> -       /*
>>>> -        * Enable runtime PM for this card
>>>> -        */
>>>> -       pm_runtime_enable(&card->dev);
>>>> +               /*
>>>> +                * Enable runtime PM for this card
>>>> +                */
>>>> +               pm_runtime_enable(&card->dev);
>>>> +       }
>>>>
>>>>        /*
>>>>         * The number of functions on the card is encoded inside
>>>> @@ -747,9 +755,10 @@ int mmc_attach_sdio(struct mmc_host *host, u32 ocr)
>>>>                        goto remove;
>>>>
>>>>                /*
>>>> -                * Enable Runtime PM for this func
>>>> +                * Enable Runtime PM for this func (if supported)
>>>>                 */
>>>> -               pm_runtime_enable(&card->sdio_func[i]->dev);
>>>> +               if (host->caps & MMC_CAP_RUNTIME_PM)
>>>> +                       pm_runtime_enable(&card->sdio_func[i]->dev);
>>>>        }
>>>>
>>>>        mmc_release_host(host);
>>>> diff --git a/drivers/mmc/core/sdio_bus.c b/drivers/mmc/core/sdio_bus.c
>>>> index 2716c7a..f3ce21b 100644
>>>> --- a/drivers/mmc/core/sdio_bus.c
>>>> +++ b/drivers/mmc/core/sdio_bus.c
>>>> @@ -17,6 +17,7 @@
>>>>  #include <linux/pm_runtime.h>
>>>>
>>>>  #include <linux/mmc/card.h>
>>>> +#include <linux/mmc/host.h>
>>>>  #include <linux/mmc/sdio_func.h>
>>>>
>>>>  #include "sdio_cis.h"
>>>> @@ -132,9 +133,11 @@ static int sdio_bus_probe(struct device *dev)
>>>>         * it should call pm_runtime_put_noidle() in its probe routine and
>>>>         * pm_runtime_get_noresume() in its remove routine.
>>>>         */
>>>> -       ret = pm_runtime_get_sync(dev);
>>>> -       if (ret < 0)
>>>> -               goto out;
>>>> +       if (func->card->host->caps & MMC_CAP_RUNTIME_PM) {
>>>> +               ret = pm_runtime_get_sync(dev);
>>>> +               if (ret < 0)
>>>> +                       goto out;
>>>> +       }
>>>>
>>>>        /* Set the default block size so the driver is sure it's something
>>>>         * sensible. */
>>>> @@ -151,7 +154,8 @@ static int sdio_bus_probe(struct device *dev)
>>>>        return 0;
>>>>
>>>>  disable_runtimepm:
>>>> -       pm_runtime_put_noidle(dev);
>>>> +       if (func->card->host->caps & MMC_CAP_RUNTIME_PM)
>>>> +               pm_runtime_put_noidle(dev);
>>>>  out:
>>>>        return ret;
>>>>  }
>>>> @@ -160,12 +164,14 @@ static int sdio_bus_remove(struct device *dev)
>>>>  {
>>>>        struct sdio_driver *drv = to_sdio_driver(dev->driver);
>>>>        struct sdio_func *func = dev_to_sdio_func(dev);
>>>> -       int ret;
>>>> +       int ret = 0;
>>>>
>>>>        /* Make sure card is powered before invoking ->remove() */
>>>> -       ret = pm_runtime_get_sync(dev);
>>>> -       if (ret < 0)
>>>> -               goto out;
>>>> +       if (func->card->host->caps & MMC_CAP_RUNTIME_PM) {
>>>> +               ret = pm_runtime_get_sync(dev);
>>>> +               if (ret < 0)
>>>> +                       goto out;
>>>> +       }
>>>>
>>>>        drv->remove(func);
>>>>
>>>> @@ -178,10 +184,12 @@ static int sdio_bus_remove(struct device *dev)
>>>>        }
>>>>
>>>>        /* First, undo the increment made directly above */
>>>> -       pm_runtime_put_noidle(dev);
>>>> +       if (func->card->host->caps & MMC_CAP_RUNTIME_PM)
>>>> +               pm_runtime_put_noidle(dev);
>>>>
>>>>        /* Then undo the runtime PM settings in sdio_bus_probe() */
>>>> -       pm_runtime_put_noidle(dev);
>>>> +       if (func->card->host->caps & MMC_CAP_RUNTIME_PM)
>>>> +               pm_runtime_put_noidle(dev);
>>>>
>>>>  out:
>>>>        return ret;
>>>> @@ -191,6 +199,8 @@ out:
>>>>
>>>>  static int sdio_bus_pm_prepare(struct device *dev)
>>>>  {
>>>> +       struct sdio_func *func = dev_to_sdio_func(dev);
>>>> +
>>>>        /*
>>>>         * Resume an SDIO device which was suspended at run time at this
>>>>         * point, in order to allow standard SDIO suspend/resume paths
>>>> @@ -212,7 +222,8 @@ static int sdio_bus_pm_prepare(struct device *dev)
>>>>         * since there is little point in failing system suspend if a
>>>>         * device can't be resumed.
>>>>         */
>>>> -       pm_runtime_resume(dev);
>>>> +       if (func->card->host->caps & MMC_CAP_RUNTIME_PM)
>>>> +               pm_runtime_resume(dev);
>>>>
>>>>        return 0;
>>>>  }
>>>> diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
>>>> index c3ffad8..e5eee0e 100644
>>>> --- a/include/linux/mmc/host.h
>>>> +++ b/include/linux/mmc/host.h
>>>> @@ -167,6 +167,7 @@ struct mmc_host {
>>>>                                                /* DDR mode at 1.8V */
>>>>  #define MMC_CAP_1_2V_DDR       (1 << 12)       /* can support */
>>>>                                                /* DDR mode at 1.2V */
>>>> +#define MMC_CAP_RUNTIME_PM     (1 << 13)       /* Can power off/on in runtime */
>>>>
>>>>        mmc_pm_flag_t           pm_caps;        /* supported pm features */
>>>>
>>>> --
>>>> 1.7.0.4
>>>>
>>>>
>>>>         
>>
>>     
>