Hello On 11/10/2010 4:28 PM, Giuseppe CAVALLARO wrote: > > Hello. > > The following patches, currently built against an ST Kernel > "2.6.32", show how to improve the wakeup support in the SDHCI > device driver. > > Note: > I'm going to rework them, for example, against the mmc-next > after performing the review process and, obviously, if you > think that they can be actually useful. > > Indeed, on a STB, it can be nice to have the capability to > wake-up the system when a card is inserted ;-). > > This work allows the SDHCI to wake up the system > on the following events: > 1) Card Interrupts. > 2) Card Insertion. > 3) Card Removal. > > To do that the sdhci has to perform some operations > described in the patch named: > "mmc_sdhci: improve the wake-up support" > > A new parameter has been also added to select which wakeup > event has to be used. At any rate, a device based on > the sdchi, e.g. sdhci-pci, can use a default mode (that > can be modified at run-time as well). > In case of the sdhci-pci the "Card Interrupt event" has not > been modified according to the logic behind the recent commit: > 5f619704d18b93869d045abc49e09cdba109b04b > > The define MMC_PM_KEEP_POWER has been used to notify that > a device driver (e.g. sdhci-pltfm) want to wakeup the system. > In any case, the logic for programming the HC register is > embedded in the suspend and it's self contained. > > In the sdhci-pltfm, it has been also introduced another fix: > see patch named: > "mmc: sdhci-pltfm calls the sdhci_alloc_host with pdev->dev" > The driver calls the sdhci_alloc_host passing as device pointer > the parent. > Note: parent name is "platform" and dev name is "sdhci.0". > IMO it makes sense to pass the pdev->dev pointer instead of the > parent. This also helps when invoke the device_set_wakeup_capable etc. > > This is a piece of output on our ST platforms: > > bash-3.00# echo 2 > /sys/module/sdhci/parameters/wakeup > bash-3.00# echo standby > /sys/power/state > > PM: Syncing filesystems ... done. > Freezing user space processes ... (elapsed 0.00 seconds) done. > Freezing remaining freezable tasks ... (elapsed 0.00 seconds) done. > [STM][PM] Analyzing the wakeup devices > [STM][PM] -> device sdhci.0 can wakeup > [STM][PM] -> device stm-asc.0 can wakeup > > [snip] > > As shown above, to modify at run time the wakeup event we can do: > bash-3.00 echo X > /sys/module/sdhci/parameters/wakeup > > where X can be: > 0: no wakeup > 1: Card Interrupts > 2: Card Insertion > 3: Card Removal > > Hmm, maybe it's worth having more parameters instead of the > wakeup. I mean, something like this (welcome feedback): > wake_on_card_int > wake_on_card_ins > wake_on_card_rem > > Welcome advice and feedback as usual. > I've reworked the patches, I sent the mailing list last week, now built against the mmc-next Git repository. I've removed some piece of the code commented by yourself (in this first thread of emails) and re-generated a single path (marked as V2). Many thanks for your advice and welcome feedback on the new patch. Regards Peppe -- 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
