libata: skip EH autopsy and recovery during suspend

[net-next-2.6.git] / drivers / ata / libata-core.c

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 4972fdf4bd31ae225e5ef11b1ee7b4921f24f3d0..932eaee5024527f4e617064726e39db808c17e87 100644 (file)
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -4281,7 +4281,7 @@ static const struct ata_blacklist_entry ata_device_blacklist [] = {
  *     The special characters ?, [, -, or *, can be matched using a set, eg. [*]
  *     Behaviour with malformed patterns is undefined, though generally reasonable.
  *
- *     Example patterns:  "SD1?",  "SD1[0-5]",  "*R0",  SD*1?[012]*xx"
+ *     Sample patterns:  "SD1?",  "SD1[0-5]",  "*R0",  "SD*1?[012]*xx"
  *
  *     This function uses one level of recursion per '*' in pattern.
  *     Since it calls _nothing_ else, and has _no_ explicit local variables,
@@ -5111,15 +5111,18 @@ void ata_qc_issue(struct ata_queued_cmd *qc)
        qc->flags |= ATA_QCFLAG_ACTIVE;
        ap->qc_active |= 1 << qc->tag;
 
-       /* We guarantee to LLDs that they will have at least one
+       /*
+        * We guarantee to LLDs that they will have at least one
         * non-zero sg if the command is a data command.
         */
-       BUG_ON(ata_is_data(prot) && (!qc->sg || !qc->n_elem || !qc->nbytes));
+       if (WARN_ON_ONCE(ata_is_data(prot) &&
+                        (!qc->sg || !qc->n_elem || !qc->nbytes)))
+               goto sys_err;
 
        if (ata_is_dma(prot) || (ata_is_pio(prot) &&
                                 (ap->flags & ATA_FLAG_PIO_DMA)))
                if (ata_sg_setup(qc))
-                       goto sg_err;
+                       goto sys_err;
 
        /* if device is sleeping, schedule reset and abort the link */
        if (unlikely(qc->dev->flags & ATA_DFLAG_SLEEPING)) {
@@ -5136,7 +5139,7 @@ void ata_qc_issue(struct ata_queued_cmd *qc)
                goto err;
        return;
 
-sg_err:
+sys_err:
        qc->err_mask |= AC_ERR_SYSTEM;
 err:
        ata_qc_complete(qc);
@@ -5415,6 +5418,7 @@ static int ata_host_request_pm(struct ata_host *host, pm_message_t mesg,
  */
 int ata_host_suspend(struct ata_host *host, pm_message_t mesg)
 {
+       unsigned int ehi_flags = ATA_EHI_QUIET;
        int rc;
 
        /*
@@ -5423,7 +5427,18 @@ int ata_host_suspend(struct ata_host *host, pm_message_t mesg)
         */
        ata_lpm_enable(host);
 
-       rc = ata_host_request_pm(host, mesg, 0, ATA_EHI_QUIET, 1);
+       /*
+        * 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;