ata: add ata port system PM callbacks

Change ata_host_request_pm to ata_port_request_pm which performs
port suspend/resume.

Add ata port type driver which implements port PM callbacks.

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

3 files changed, 76 insertions, 70 deletions

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index c04ad68cb602..04c208e3cec6 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -5234,112 +5234,116 @@ bool ata_link_offline(struct ata_link *link)
 }
 
 #ifdef CONFIG_PM
-static int ata_host_request_pm(struct ata_host *host, pm_message_t mesg,
+static int ata_port_request_pm(struct ata_port *ap, pm_message_t mesg,
                                unsigned int action, unsigned int ehi_flags,
                                int wait)
 {
+        struct ata_link *link;
         unsigned long flags;
-        int i, rc;
-
-        for (i = 0; i < host->n_ports; i++) {
-                struct ata_port *ap = host->ports[i];
-                struct ata_link *link;
+        int rc;
 
-                /* Previous resume operation might still be in
-                 * progress.  Wait for PM_PENDING to clear.
-                 */
-                if (ap->pflags & ATA_PFLAG_PM_PENDING) {
-                        ata_port_wait_eh(ap);
-                        WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
-                }
+        /* Previous resume operation might still be in
+         * progress.  Wait for PM_PENDING to clear.
+         */
+        if (ap->pflags & ATA_PFLAG_PM_PENDING) {
+                ata_port_wait_eh(ap);
+                WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
+        }
 
-                /* request PM ops to EH */
-                spin_lock_irqsave(ap->lock, flags);
+        /* request PM ops to EH */
+        spin_lock_irqsave(ap->lock, flags);
 
-                ap->pm_mesg = mesg;
-                if (wait) {
-                        rc = 0;
-                        ap->pm_result = &rc;
-                }
+        ap->pm_mesg = mesg;
+        if (wait) {
+                rc = 0;
+                ap->pm_result = &rc;
+        }
 
-                ap->pflags |= ATA_PFLAG_PM_PENDING;
-                ata_for_each_link(link, ap, HOST_FIRST) {
-                        link->eh_info.action |= action;
-                        link->eh_info.flags |= ehi_flags;
-                }
+        ap->pflags |= ATA_PFLAG_PM_PENDING;
+        ata_for_each_link(link, ap, HOST_FIRST) {
+                link->eh_info.action |= action;
+                link->eh_info.flags |= ehi_flags;
+        }
 
-                ata_port_schedule_eh(ap);
+        ata_port_schedule_eh(ap);
 
-                spin_unlock_irqrestore(ap->lock, flags);
+        spin_unlock_irqrestore(ap->lock, flags);
 
-                /* wait and check result */
-                if (wait) {
-                        ata_port_wait_eh(ap);
-                        WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
-                        if (rc)
-                                return rc;
-                }
+        /* wait and check result */
+        if (wait) {
+                ata_port_wait_eh(ap);
+                WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
         }
 
-        return 0;
+        return rc;
 }
 
+#define to_ata_port(d) container_of(d, struct ata_port, tdev)
+
+static int ata_port_suspend_common(struct device *dev)
+{
+        struct ata_port *ap = to_ata_port(dev);
+        int rc;
+
+        rc = ata_port_request_pm(ap, PMSG_SUSPEND, 0, ATA_EHI_QUIET, 1);
+        return rc;
+}
+
+static int ata_port_suspend(struct device *dev)
+{
+        if (pm_runtime_suspended(dev))
+                return 0;
+
+        return ata_port_suspend_common(dev);
+}
+
+static int ata_port_resume(struct device *dev)
+{
+        struct ata_port *ap = to_ata_port(dev);
+        int rc;
+
+        rc = ata_port_request_pm(ap, PMSG_ON, ATA_EH_RESET,
+                ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET, 1);
+        return rc;
+}
+
+static const struct dev_pm_ops ata_port_pm_ops = {
+        .suspend = ata_port_suspend,
+        .resume = ata_port_resume,
+};
+
 /**
  *      ata_host_suspend - suspend host
  *      @host: host to suspend
  *      @mesg: PM message
  *
- *      Suspend @host.  Actual operation is performed by EH.  This
- *      function requests EH to perform PM operations and waits for EH
- *      to finish.
- *
- *      LOCKING:
- *      Kernel thread context (may sleep).
- *
- *      RETURNS:
- *      0 on success, -errno on failure.
+ *      Suspend @host.  Actual operation is performed by port suspend.
  */
 int ata_host_suspend(struct ata_host *host, pm_message_t mesg)
 {
-        unsigned int ehi_flags = ATA_EHI_QUIET;
-        int rc;
-
-        /*
-         * On some hardware, device fails to respond after spun down
-         * for suspend.  As the device won't be used before being
-         * resumed, we don't need to touch the device.  Ask EH to skip
-         * the usual stuff and proceed directly to suspend.
-         *
-         * http://thread.gmane.org/gmane.linux.ide/46764
-         */
-        if (mesg.event == PM_EVENT_SUSPEND)
-                ehi_flags |= ATA_EHI_NO_AUTOPSY | ATA_EHI_NO_RECOVERY;
-
-        rc = ata_host_request_pm(host, mesg, 0, ehi_flags, 1);
-        if (rc == 0)
-                host->dev->power.power_state = mesg;
-        return rc;
+        host->dev->power.power_state = mesg;
+        return 0;
 }
 
 /**
  *      ata_host_resume - resume host
  *      @host: host to resume
  *
- *      Resume @host.  Actual operation is performed by EH.  This
- *      function requests EH to perform PM operations and returns.
- *      Note that all resume operations are performed parallelly.
- *
- *      LOCKING:
- *      Kernel thread context (may sleep).
+ *      Resume @host.  Actual operation is performed by port resume.
  */
 void ata_host_resume(struct ata_host *host)
 {
-        ata_host_request_pm(host, PMSG_ON, ATA_EH_RESET,
-                            ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET, 0);
         host->dev->power.power_state = PMSG_ON;
 }
 #endif
 
+struct device_type ata_port_type = {
+        .name = "ata_port",
+#ifdef CONFIG_PM
+        .pm = &ata_port_pm_ops,
+#endif
+};
+
 /**
  *      ata_dev_init - Initialize an ata_device structure
  *      @dev: Device structure to initialize
diff --git a/drivers/ata/libata-transport.c b/drivers/ata/libata-transport.c
index ce9dc6207f37..3ceb3d94be26 100644
--- a/drivers/ata/libata-transport.c
+++ b/drivers/ata/libata-transport.c
@@ -279,6 +279,7 @@ int ata_tport_add(struct device *parent,
         struct device *dev = &ap->tdev;
 
         device_initialize(dev);
+        dev->type = &ata_port_type;
 
         dev->parent = get_device(parent);
         dev->release = ata_tport_release;
diff --git a/drivers/ata/libata.h b/drivers/ata/libata.h
index 773de97988a2..814486d35c44 100644
--- a/drivers/ata/libata.h
+++ b/drivers/ata/libata.h
@@ -58,6 +58,7 @@ extern int atapi_passthru16;
 extern int libata_fua;
 extern int libata_noacpi;
 extern int libata_allow_tpm;
+extern struct device_type ata_port_type;
 extern struct ata_link *ata_dev_phys_link(struct ata_device *dev);
 extern void ata_force_cbl(struct ata_port *ap);
 extern u64 ata_tf_to_lba(const struct ata_taskfile *tf);