> From: Ulf Hansson > <[email protected]<mailto:[email protected]>> > Date: Fri, Mar 1, 2013 at 8:47 PM > Subject: [PATCH 0/3] mmc: Use runtime pm for blkdevice > To: [email protected]<mailto:[email protected]>, Chris Ball > <[email protected]<mailto:[email protected]>> > Cc: Johan Rudholm > <[email protected]<mailto:[email protected]>>, Ulf > Hansson <[email protected]<mailto:[email protected]>> > > > From: Ulf Hansson <[email protected]<mailto:[email protected]>> > > SDIO has been using runtime pm for a while to handle runtime power save > operations. This patchset is enabling the option to make the sd/mmc > blockdevices to use runtime pm as well. > > The runtime pm implementation for the block device will make use of > autosuspend to defer power save operation to after request inactivty for > a certain time. > > To actually perform some power save operations the corresponding bus ops > for mmc and sd shall be implemented. Typically it could make sense to do > BKOPS for eMMC in here. > > Ulf Hansson (3): > mmc: core: Remove power_restore bus_ops for mmc and sd > mmc: core: Add bus_ops for runtime pm callbacks > mmc: block: Enable runtime pm for mmc blkdevice > Ulf,
sdhci.c has added pm_runtime which also protect between request and task finish. And some sdhci.c based host drivers has provided pm_runtime_suspend/resume functions like sdhci-pxav3.c. From the powersave viewpoint, I think adding pm_runtime in driver level is better than doing that on bus level since the control granularity is even smaller. And adding pm_runtime in both block.c and sdhci.c will call pm_runtime twice. How do you think? Thanks Kevin -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
