On Wed, Jun 20, 2012 at 6:26 PM, Lin Ming <ming.m.lin@xxxxxxxxx> wrote: > On Wed, 2012-06-20 at 16:50 -0700, Dan Williams wrote: >> On Sun, Jun 17, 2012 at 11:25 PM, Lin Ming <ming.m.lin@xxxxxxxxx> wrote: >> > From: Matthew Garrett <mjg@xxxxxxxxxx> >> > >> > Associate the ACPI device tree and libata devices. >> > This patch uses the generic ACPI glue framework to do so. >> > >> > Signed-off-by: Matthew Garrett <mjg@xxxxxxxxxx> >> > Signed-off-by: Holger Macht <holger@xxxxxxxx> >> > Signed-off-by: Lin Ming <ming.m.lin@xxxxxxxxx> >> > --- >> > >> > Changelog: >> > >> > - fixed crash reported at https://lkml.org/lkml/2012/2/24/2 (Aaron Lu) >> > - rename is_pci_ata to compat_pci_ata (Alan Cox) >> > >> > drivers/acpi/glue.c | 4 +- >> > drivers/ata/libata-acpi.c | 125 +++++++++++++++++++++++++++++++++++++++++++++ >> > drivers/ata/libata-core.c | 3 ++ >> > drivers/ata/libata.h | 4 ++ >> > 4 files changed, 134 insertions(+), 2 deletions(-) >> > >> > diff --git a/drivers/acpi/glue.c b/drivers/acpi/glue.c >> > index 1564e09..18d6812 100644 >> > --- a/drivers/acpi/glue.c >> > +++ b/drivers/acpi/glue.c >> [..] >> > +static int ata_acpi_bind_host(struct device *dev, int host, acpi_handle *handle) >> > +{ >> > + struct Scsi_Host *shost = dev_to_shost(dev); >> > + struct ata_port *ap = ata_shost_to_port(shost); >> > + >> > + if (ap->flags & ATA_FLAG_ACPI_SATA) >> > + return -ENODEV; >> > + >> > + *handle = acpi_get_child(DEVICE_ACPI_HANDLE(dev->parent), ap->port_no); >> > + >> > + if (!*handle) >> > + return -ENODEV; >> > + >> > + return 0; >> > +} >> >> I think this patch should be squashed with patch 4, right? That is if >> we keep the hard-coded ->parent chasing... > > Right. Will merge patch 4. > >> >> > +static int ata_acpi_find_device(struct device *dev, acpi_handle *handle) >> > +{ >> > + unsigned int host, channel, id, lun; >> > + >> > + if (sscanf(dev_name(dev), "host%u", &host) == 1) { >> > + if (!compat_pci_ata(dev->parent)) >> > + return -ENODEV; >> > + >> > + return ata_acpi_bind_host(dev, host, handle); >> > + } else if (sscanf(dev_name(dev), "%d:%d:%d:%d", >> > + &host, &channel, &id, &lun) == 4) { >> > + if (!compat_pci_ata(dev->parent->parent->parent)) >> > + return -ENODEV; >> >> ...this looks like it should be using a dev_to_ata_port() helper which >> like dev_to_shost() skips the need to remember just how many parents >> until we get back to our ata_port, scsi_host, etc. > > Oh, no. > > compat_pci_ata checks whether the controller(rather than shost or ata > port) is pci SATA/IDE controller. > > As in patch 4: > compat_pci_ata(dev->parent->parent->parent->parent) > > The "dev" is ata port, and dev->parent->parent->parent->parent points to > the controller dev. > > This looks ugly. How about add two helpers? > shost_to_controller(dev) and ata_port_to_controller(dev) > What about something like the following (untested)? Makes it mostly independent of the topology, gives some type safety, and drops some redundant work finding the ata_port. static int ata_acpi_find_device(struct device *dev, acpi_handle *handle) { struct ata_port *ap = dev_to_ata_port(dev); if (!ap) return -ENODEV; if (!compat_pci_ata(ap)) return -ENODEV; if (scsi_is_host_device(dev)) return ata_acpi_bind_host(ap, handle); else if (scsi_is_sdev_device(dev)) { struct scsi_device *sdev = to_scsi_device(dev); return ata_acpi_bind_device(ap, sdev->channel, sdev->id, handle); } else return -ENODEV; } -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
