[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/ata_piix.c b/drivers/scsi/ata_piix.c
index 0ea2787..f796303 100644 (file)
--- a/drivers/scsi/ata_piix.c
+++ b/drivers/scsi/ata_piix.c
@@ -166,6 +166,8 @@ static struct pci_driver piix_pci_driver = {
        .id_table               = piix_pci_tbl,
        .probe                  = piix_init_one,
        .remove                 = ata_pci_remove_one,
+       .suspend                = ata_pci_device_suspend,
+       .resume                 = ata_pci_device_resume,
 };
 
 static struct scsi_host_template piix_sht = {
@@ -186,6 +188,8 @@ static struct scsi_host_template piix_sht = {
        .slave_configure        = ata_scsi_slave_config,
        .bios_param             = ata_std_bios_param,
        .ordered_flush          = 1,
+       .resume                 = ata_scsi_device_resume,
+       .suspend                = ata_scsi_device_suspend,
 };
 
 static const struct ata_port_operations piix_pata_ops = {

diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index 9ea1025..9c66d40 100644 (file)
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -4154,6 +4154,96 @@ err_out:
  *     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 @@ int pci_test_config_bits(struct pci_dev *pdev, const struct pci_bits *bits)
 
        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_host_stop);
 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);

diff --git a/drivers/scsi/libata-scsi.c b/drivers/scsi/libata-scsi.c
index e0439be..c1ebede 100644 (file)
--- a/drivers/scsi/libata-scsi.c
+++ b/drivers/scsi/libata-scsi.c
@@ -396,6 +396,22 @@ void ata_dump_status(unsigned id, struct ata_taskfile *tf)
        }
 }
 
+int ata_scsi_device_resume(struct scsi_device *sdev)
+{
+       struct ata_port *ap = (struct ata_port *) &sdev->host->hostdata[0];
+       struct ata_device *dev = &ap->device[sdev->id];
+
+       return ata_device_resume(ap, dev);
+}
+
+int ata_scsi_device_suspend(struct scsi_device *sdev)
+{
+       struct ata_port *ap = (struct ata_port *) &sdev->host->hostdata[0];
+       struct ata_device *dev = &ap->device[sdev->id];
+
+       return ata_device_suspend(ap, dev);
+}
+
 /**
  *     ata_to_sense_error - convert ATA error to SCSI error
  *     @id: ATA device number

diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
index 15842b1..ea7f3a4 100644 (file)
--- a/drivers/scsi/scsi_sysfs.c
+++ b/drivers/scsi/scsi_sysfs.c
@@ -263,9 +263,40 @@ static int scsi_bus_match(struct device *dev, struct device_driver *gendrv)
        return (sdp->inq_periph_qual == SCSI_INQ_PQ_CON)? 1: 0;
 }
 
+static int scsi_bus_suspend(struct device * dev, pm_message_t state)
+{
+       struct scsi_device *sdev = to_scsi_device(dev);
+       struct scsi_host_template *sht = sdev->host->hostt;
+       int err;
+
+       err = scsi_device_quiesce(sdev);
+       if (err)
+               return err;
+
+       if (sht->suspend)
+               err = sht->suspend(sdev);
+
+       return err;
+}
+
+static int scsi_bus_resume(struct device * dev)
+{
+       struct scsi_device *sdev = to_scsi_device(dev);
+       struct scsi_host_template *sht = sdev->host->hostt;
+       int err = 0;
+
+       if (sht->resume)
+               err = sht->resume(sdev);
+
+       scsi_device_resume(sdev);
+       return err;
+}
+
 struct bus_type scsi_bus_type = {
         .name          = "scsi",
         .match         = scsi_bus_match,
+       .suspend        = scsi_bus_suspend,
+       .resume         = scsi_bus_resume,
 };
 
 int scsi_sysfs_register(void)

diff --git a/include/linux/ata.h b/include/linux/ata.h
index d2873b7..3eb80c3 100644 (file)
--- a/include/linux/ata.h
+++ b/include/linux/ata.h
@@ -141,6 +141,8 @@ enum {
        ATA_CMD_PACKET          = 0xA0,
        ATA_CMD_VERIFY          = 0x40,
        ATA_CMD_VERIFY_EXT      = 0x42,
+       ATA_CMD_STANDBYNOW1     = 0xE0,
+       ATA_CMD_IDLEIMMEDIATE   = 0xE1,
        ATA_CMD_INIT_DEV_PARAMS = 0x91,
 
        /* SETFEATURES stuff */

diff --git a/include/linux/libata.h b/include/linux/libata.h
index e828e17..cdab75c 100644 (file)
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -124,6 +124,8 @@ enum {
        ATA_FLAG_DEBUGMSG       = (1 << 10),
        ATA_FLAG_NO_ATAPI       = (1 << 11), /* No ATAPI support */
 
+       ATA_FLAG_SUSPENDED      = (1 << 12), /* port is suspended */
+
        ATA_QCFLAG_ACTIVE       = (1 << 1), /* cmd not yet ack'd to scsi lyer */
        ATA_QCFLAG_SG           = (1 << 3), /* have s/g table? */
        ATA_QCFLAG_SINGLE       = (1 << 4), /* no s/g, just a single buffer */
@@ -436,6 +438,8 @@ extern void ata_std_ports(struct ata_ioports *ioaddr);
 extern int ata_pci_init_one (struct pci_dev *pdev, struct ata_port_info **port_info,
                             unsigned int n_ports);
 extern void ata_pci_remove_one (struct pci_dev *pdev);
+extern int ata_pci_device_suspend(struct pci_dev *pdev, pm_message_t state);
+extern int ata_pci_device_resume(struct pci_dev *pdev);
 #endif /* CONFIG_PCI */
 extern int ata_device_add(const struct ata_probe_ent *ent);
 extern void ata_host_set_remove(struct ata_host_set *host_set);
@@ -445,6 +449,10 @@ extern int ata_scsi_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmn
 extern int ata_scsi_error(struct Scsi_Host *host);
 extern int ata_scsi_release(struct Scsi_Host *host);
 extern unsigned int ata_host_intr(struct ata_port *ap, struct ata_queued_cmd *qc);
+extern int ata_scsi_device_resume(struct scsi_device *);
+extern int ata_scsi_device_suspend(struct scsi_device *);
+extern int ata_device_resume(struct ata_port *, struct ata_device *);
+extern int ata_device_suspend(struct ata_port *, struct ata_device *);
 extern int ata_ratelimit(void);
 
 /*

diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h
index 6cbb198..6297885 100644 (file)
--- a/include/scsi/scsi_host.h
+++ b/include/scsi/scsi_host.h
@@ -295,6 +295,12 @@ struct scsi_host_template {
         */
        int (*proc_info)(struct Scsi_Host *, char *, char **, off_t, int, int);
 
+       /*
+        * suspend support
+        */
+       int (*resume)(struct scsi_device *);
+       int (*suspend)(struct scsi_device *);
+
        /*
         * Name of proc directory
         */