On Mon, Sep 24, 2012 at 11:46:03PM +0200, Rafael J. Wysocki wrote: > On Monday, September 24, 2012, Aaron Lu wrote: > > On Mon, Sep 24, 2012 at 03:06:11PM +0200, Rafael J. Wysocki wrote: > > > On Monday, September 24, 2012, Aaron Lu wrote: > > > > need_eject: > > > > First consider how the device will be runtime resumed: > > > > 1 Some program opens the block device; > > > > 2 Events checking poll when it's not powered off yet; > > > > 3 User presses the eject button or inserts a disc into the slot when the > > > > device is in powered off state. > > > > And the need_eject flag is for case 3, when the device is in powered off > > > > state and user presses the eject button, it will be powered on(through > > > > acpi wake notification function) and runtime resumed. In its runtime > > > > resume callback, its tray needs to be ejected since user just presses > > > > the eject button. The whole process of ZPODD is opaque to the user, > > > > he/she doesn't know the ODD lost power so the ODD has to behave exactly > > > > like it doesn't lose power. > > > > > > Do you think it can be useful for other types of devices, not necessarily > > > handled through ACPI? > > > > I can only say that it is useful for ZPODD, if ZPODD someday is used on > > another platform that does not use ACPI, the need_eject flag should > > still be needed. > > > > As for other scsi devices, I'm not sure. > > I see. This means we don't really have good arguments for putting that flag > into struct scsi_device ... OK. I'm thinking of moving the acpi wake notification code from ata to scsi, so that the notification function lives in sr module and then I do not need to set this need_eject flag in scsi_device and scsi_cd structure needs to host this flag. A example patch would be something like the following, I didn't seperate these ACPI calls in sr.c as this is just a concept proof, if this is the right thing to do, I will separate them into another file sr-acpi.c and make empty stubs for them in sr.h for systems do not have ACPI configured. diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c index ef72682..94d17f1 100644 --- a/drivers/scsi/sr.c +++ b/drivers/scsi/sr.c @@ -46,6 +46,7 @@ #include <linux/mutex.h> #include <linux/slab.h> #include <linux/pm_runtime.h> +#include <linux/acpi.h> #include <asm/uaccess.h> #include <scsi/scsi.h> @@ -57,6 +58,8 @@ #include <scsi/scsi_host.h> #include <scsi/scsi_ioctl.h> /* For the door lock/unlock commands */ +#include <acpi/acpi_bus.h> + #include "scsi_logging.h" #include "sr.h" @@ -212,8 +220,8 @@ static int sr_resume(struct device *dev) scsi_test_unit_ready(cd->device, SR_TIMEOUT, MAX_RETRIES, &sshdr); /* If user wakes up the ODD, eject the tray */ - if (cd->device->need_eject) { - cd->device->need_eject = 0; + if (cd->need_eject) { + cd->need_eject = false; /* But only for tray type ODD when door is not locked */ if (!(cd->cdi.mask & CDC_CLOSE_TRAY) && !cd->door_locked) sr_tray_move(&cd->cdi, 1); @@ -704,6 +711,58 @@ static void sr_release(struct cdrom_device_info *cdi) } +static void sr_acpi_wake_dev(acpi_handle handle, u32 event, void *context) +{ + struct device *dev = context; + struct scsi_cd *cd = dev_get_drvdata(dev); + + if (event == ACPI_NOTIFY_DEVICE_WAKE && pm_runtime_suspended(dev)) { + cd->need_eject = true; + pm_runtime_resume(dev); + } +} + +static void sr_acpi_add_pm_notifier(struct device *dev) +{ + struct acpi_device *acpi_dev; + acpi_handle handle; + acpi_status status; + + handle = dev->archdata.acpi_handle; + if (!handle) + return; + + status = acpi_bus_get_device(handle, &acpi_dev); + if (ACPI_FAILURE(status)) + return; + + acpi_power_resource_register_device(dev, handle); + acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY, + sr_acpi_wake_dev, dev); + device_set_run_wake(dev, true); +} + +static void sr_acpi_remove_pm_notifier(struct device *dev) +{ + struct acpi_device *acpi_dev; + acpi_handle handle; + acpi_status status; + + handle = dev->archdata.acpi_handle; + if (!handle) + return; + + status = acpi_bus_get_device(handle, &acpi_dev); + if (ACPI_FAILURE(status)) + return; + + acpi_power_resource_unregister_device(dev, handle); + device_set_run_wake(dev, false); + acpi_remove_notify_handler(handle, ACPI_SYSTEM_NOTIFY, sr_acpi_wake_dev); +} + static int sr_probe(struct device *dev) { struct scsi_device *sdev = to_scsi_device(dev); @@ -786,7 +845,9 @@ static int sr_probe(struct device *dev) sdev_printk(KERN_DEBUG, sdev, "Attached scsi CD-ROM %s\n", cd->cdi.name); - /* enable runtime pm */ + if (sdev->can_power_off) + sr_acpi_add_pm_notifier(dev); + scsi_autopm_put_device(cd->device); return 0; @@ -1036,8 +1097,9 @@ static int sr_remove(struct device *dev) { struct scsi_cd *cd = dev_get_drvdata(dev); - /* disable runtime pm */ scsi_autopm_get_device(cd->device); + if (cd->device->can_power_off) + sr_acpi_remove_pm_notifier(dev); blk_queue_prep_rq(cd->device->request_queue, scsi_prep_fn); del_gendisk(cd->disk); Thanks, Aaron -- 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