v10: Introduce PM_QOS_NO_POLL flag to skip calling disk's events_check callback; Do not use zero power ready hint information from event poll; Check attached device in port's runtime idle callback to decide if suspend is desired; Address various comments from Tejun Heo. v9: Build ZPODD as part of libata instead of another standalone module as it is tightly related to other libata files. Identify and init ZPODD during probe time instead of after SCSI device is created as suggested by Tejun Heo. Make use of pm qos flag to give ACPI hint when choosing ACPI state. Expose qos flag to give user control of whether power off is allowed. This patchset used Rafael's pm-qos work: git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git pm-qos v8: This version is a redesign, it doesn't have much to do with previous versions. The ZPODD implementation is done almost entirely in ATA layer now, except 2 helper functions from SCSI sr driver to block disk events. The basic idea is that, when ata port is runtime suspended, it will check if the ODD is ready to be powered off. And if yes, events is blocked and power omitted; if not, ODD's power supply remains unchanged by keeping ACPI state at D0. Some background knowledge about ZPODD is added below v1 history log. v7: Re work of runtime pm of sr driver, based on ideas of Alan Stern and Oliver Neukum. Jeff, due to the ready_to_power_off flag added, there is a small change in [PATCH v7 6/6] libata: acpi: respect may_power_off flag, please check if I can still get your ack, thanks. v6: When user changes may_power_off flag through sysfs entry and if device is already runtime suspended, resume resume it so that it can respect this flag next time it is runtime suspended as suggested by Alan Stern. Call scsi_autopm_get/put_device once in sr_check_events as suggested by Alan Stern. v5: Add may_power_off flag to scsi device. Alan Stern suggested that I should not mess runtime suspend with runtime power off, but the current zpodd implementation made it not easy to seperate. So I re-wrote the zpodd implementation, the end result is, normal ODD can also enter runtime suspended state, but their power won't be removed. v4: Rebase on top of Linus' tree, due to this, the problem of a missing flag in v3 is gone; Add a new function scsi_autopm_put_device_autosuspend to first mark last busy for the device and then put autosuspend it as suggested by Oliver Neukum. Typo fix as pointed by Sergei Shtylyov. Check can_power_off flag before any runtime pm operations in sr. v3: Rebase on top of scsi-misc tree; Add the sr related patches previously in Jeff's libata tree; Re-organize the sr patches. A problem for now: for patch scsi: sr: support zero power ODD(ZPODD) I can't set a flag in libata-acpi.c since a related function is missing in scsi-misc tree. Will fix this when 3.6-rc1 released. v2: Bug fix for v1; Use scsi_autopm_* in sr driver instead of pm_runtime_*; v1: Here are some patches to make ZPODD easier to use for end users and a fix for using ZPODD with system suspend. Some background knowledge about ZPODD: ODD means Optical Disc Drive. ZPODD means Zero Power ODD, it is a mechanism to place the ODD into zero power state when the system is running at S0 system state without user's awareness. It achieved this by ACPI and SATA device attention pin. For power off, normal ACPI control method is used to place the device into D3 cold ACPI device state, aka. device power supply omitted. For power on, when user press the eject button of a drawer type ODD or when user inserts an ODD into a slot type ODD, the device attention pin will trigger. In the current x86 implementation, this pin will connect to a GPE, and the GPE will trigger an ACPI interrupt. With our pre-registered ACPI notification code, the device can be runtime resumed, and we place the device back to full power state by setting its ACPI state to D0. The whole process is transparent to the end user. Aaron Lu (10): scsi: sr: support runtime pm libata: Add CONFIG_SATA_ZPODD libata: identify and init ZPODD devices libata: move acpi notification code to zpodd libata: check zero power ready status for ZPODD libata: handle power transition of ODD libata: expose pm qos flags to user space for ata device PM / BLOCK: add PM_QOS_FLAG_NO_POLL to skip events checking libata: use PM_QOS_FLAG_NO_POLL to avoid events checking for ZPODD libata: do not suspend port if normal ODD is attached block/genhd.c | 8 +- drivers/ata/Kconfig | 13 +++ drivers/ata/Makefile | 1 + drivers/ata/libata-acpi.c | 116 ++++++------------- drivers/ata/libata-core.c | 23 +++- drivers/ata/libata-eh.c | 12 +- drivers/ata/libata-zpodd.c | 282 +++++++++++++++++++++++++++++++++++++++++++++ drivers/ata/libata.h | 27 +++++ drivers/scsi/sr.c | 30 ++++- include/linux/libata.h | 5 + include/linux/pm_qos.h | 1 + include/uapi/linux/cdrom.h | 34 ++++++ 12 files changed, 463 insertions(+), 89 deletions(-) create mode 100644 drivers/ata/libata-zpodd.c -- 1.7.12.4 -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
