[PATCH] Suspend support for libata
This patch adds suspend patch to libata, and ata_piix in particular. For
most low level drivers, they should just need to add the 4 hooks to
work. As I can only test ata_piix, I didn't enable it for more
though.
Suspend support is the single most important feature on a notebook, and
most new notebooks have sata drives. It's quite embarrassing that we
_still_ do not support this. Right now, it's perfectly possible to
suspend the drive in mid-transfer.
Signed-off-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index 9ea10258..9c66d40 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -4154,6 +4154,96 @@
* Inherited from caller.
*/
+/*
+ * Execute a 'simple' command, that only consists of the opcode 'cmd' itself,
+ * without filling any other registers
+ */
+static int ata_do_simple_cmd(struct ata_port *ap, struct ata_device *dev,
+ u8 cmd)
+{
+ struct ata_taskfile tf;
+ int err;
+
+ ata_tf_init(ap, &tf, dev->devno);
+
+ tf.command = cmd;
+ tf.flags |= ATA_TFLAG_DEVICE;
+ tf.protocol = ATA_PROT_NODATA;
+
+ err = ata_exec_internal(ap, dev, &tf, DMA_NONE, NULL, 0);
+ if (err)
+ printk(KERN_ERR "%s: ata command failed: %d\n",
+ __FUNCTION__, err);
+
+ return err;
+}
+
+static int ata_flush_cache(struct ata_port *ap, struct ata_device *dev)
+{
+ u8 cmd;
+
+ if (!ata_try_flush_cache(dev))
+ return 0;
+
+ if (ata_id_has_flush_ext(dev->id))
+ cmd = ATA_CMD_FLUSH_EXT;
+ else
+ cmd = ATA_CMD_FLUSH;
+
+ return ata_do_simple_cmd(ap, dev, cmd);
+}
+
+static int ata_standby_drive(struct ata_port *ap, struct ata_device *dev)
+{
+ return ata_do_simple_cmd(ap, dev, ATA_CMD_STANDBYNOW1);
+}
+
+static int ata_start_drive(struct ata_port *ap, struct ata_device *dev)
+{
+ return ata_do_simple_cmd(ap, dev, ATA_CMD_IDLEIMMEDIATE);
+}
+
+/**
+ * ata_device_resume - wakeup a previously suspended devices
+ *
+ * Kick the drive back into action, by sending it an idle immediate
+ * command and making sure its transfer mode matches between drive
+ * and host.
+ *
+ */
+int ata_device_resume(struct ata_port *ap, struct ata_device *dev)
+{
+ if (ap->flags & ATA_FLAG_SUSPENDED) {
+ ap->flags &= ~ATA_FLAG_SUSPENDED;
+ ata_set_mode(ap);
+ }
+ if (!ata_dev_present(dev))
+ return 0;
+ if (dev->class == ATA_DEV_ATA)
+ ata_start_drive(ap, dev);
+
+ return 0;
+}
+
+/**
+ * ata_device_suspend - prepare a device for suspend
+ *
+ * Flush the cache on the drive, if appropriate, then issue a
+ * standbynow command.
+ *
+ */
+int ata_device_suspend(struct ata_port *ap, struct ata_device *dev)
+{
+ if (!ata_dev_present(dev))
+ return 0;
+ if (dev->class == ATA_DEV_ATA)
+ ata_flush_cache(ap, dev);
+
+ ata_standby_drive(ap, dev);
+ ap->flags |= ATA_FLAG_SUSPENDED;
+ return 0;
+}
+
int ata_port_start (struct ata_port *ap)
{
struct device *dev = ap->host_set->dev;
@@ -4902,6 +4992,23 @@
return (tmp == bits->val) ? 1 : 0;
}
+
+int ata_pci_device_suspend(struct pci_dev *pdev, pm_message_t state)
+{
+ pci_save_state(pdev);
+ pci_disable_device(pdev);
+ pci_set_power_state(pdev, PCI_D3hot);
+ return 0;
+}
+
+int ata_pci_device_resume(struct pci_dev *pdev)
+{
+ pci_set_power_state(pdev, PCI_D0);
+ pci_restore_state(pdev);
+ pci_enable_device(pdev);
+ pci_set_master(pdev);
+ return 0;
+}
#endif /* CONFIG_PCI */
@@ -5005,4 +5112,11 @@
EXPORT_SYMBOL_GPL(ata_pci_init_native_mode);
EXPORT_SYMBOL_GPL(ata_pci_init_one);
EXPORT_SYMBOL_GPL(ata_pci_remove_one);
+EXPORT_SYMBOL_GPL(ata_pci_device_suspend);
+EXPORT_SYMBOL_GPL(ata_pci_device_resume);
#endif /* CONFIG_PCI */
+
+EXPORT_SYMBOL_GPL(ata_device_suspend);
+EXPORT_SYMBOL_GPL(ata_device_resume);
+EXPORT_SYMBOL_GPL(ata_scsi_device_suspend);
+EXPORT_SYMBOL_GPL(ata_scsi_device_resume);