The rtsx_usb_sdmmc (mmc/sd) and rtsx_usb_ms (memstick) devices are interfacing an rtsx_usb device (managed by an mfd driver) while communicating with the cards. The mmc/sd and memstick devices are children of the usb device.
Issues has been reported  for rtsx, which have been investigated, discussed, fixed, tested, etc, particularly when using mmc/sd cards. During the investigation, some changes was proposed and tested successfully. In this series I have picked up these changes and created some proper patches with change-logs. It turned out that most of the problems was related to the runtime PM deployment in the memstick and the mmc/sd driver, which are fixed in this series. A couple of more issues were also discussed , which needs to be fixed as well. Although they are out of scope for this series, so we will have to look into those at a later point. Here's a brief summary of these leftovers: *) It seems reasonable to turn off autosuspend for usb devices and instead rely on the usb device's children to deal with autosuspend. The reason is simply that the children has better knowledge of when using autosuspend makes sense. **) Polling card detect mode is used both for mmc/sd and memstick. Because of the lack of synchronization between the polling attempts for these subsystems, the usb device may be powered on for unnecessary long intervals, thus we are wasting power. Besides the above changes, I folded in a change in the mmc core which improves the behaviour for mmc hosts using MMC_CAP2_NO_PRESCAN_POWERUP, which is the case for the rtsx_usb_sdmmc driver. This change should improve the boot time with ~100ms per rtsx_usb_sdmmc device. Finally, as I couldn't find an active maintainer for the memstick subsystem/driver and because the author of the drivers can be reached, I volunteer to take this all through my mmc tree. Please tell me if that is problem to any of you.  https://www.spinics.net/lists/linux-usb/msg146998.html  https://www.spinics.net/lists/linux-mmc/msg39235.html Alan Stern (1): memstick: rtsx_usb_ms: Runtime resume the device when polling for cards Ulf Hansson (5): mmc: rtsx_usb_sdmmc: Avoid keeping the device runtime resumed when unused mmc: rtsx_usb_sdmmc: Handle runtime PM while changing the led memstick: rtsx_usb_ms: Manage runtime PM when accessing the device mmc: rtsx_usb_sdmmc: Enable runtime PM autosuspend mmc: core: Don't power off the card when starting the host drivers/memstick/host/rtsx_usb_ms.c | 6 ++++++ drivers/mmc/core/core.c | 9 ++++----- drivers/mmc/host/rtsx_usb_sdmmc.c | 10 +++++----- 3 files changed, 15 insertions(+), 10 deletions(-) -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html