1 files changed, 98 insertions, 0 deletions

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index eaead76c9443..3bad6f189190 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -3311,6 +3311,103 @@ int ata_do_set_mode(struct ata_link *link, struct ata_device **r_failed_dev)
 }
 
 /**
+ *      ata_wait_ready - wait for link to become ready
+ *      @link: link to be waited on
+ *      @deadline: deadline jiffies for the operation
+ *      @check_ready: callback to check link readiness
+ *
+ *      Wait for @link to become ready.  @check_ready should return
+ *      positive number if @link is ready, 0 if it isn't, -ENODEV if
+ *      link doesn't seem to be occupied, other errno for other error
+ *      conditions.
+ *
+ *      Transient -ENODEV conditions are allowed for
+ *      ATA_TMOUT_FF_WAIT.
+ *
+ *      LOCKING:
+ *      EH context.
+ *
+ *      RETURNS:
+ *      0 if @linke is ready before @deadline; otherwise, -errno.
+ */
+int ata_wait_ready(struct ata_link *link, unsigned long deadline,
+                   int (*check_ready)(struct ata_link *link))
+{
+        unsigned long start = jiffies;
+        unsigned long nodev_deadline = start + ATA_TMOUT_FF_WAIT;
+        int warned = 0;
+
+        if (time_after(nodev_deadline, deadline))
+                nodev_deadline = deadline;
+
+        while (1) {
+                unsigned long now = jiffies;
+                int ready, tmp;
+
+                ready = tmp = check_ready(link);
+                if (ready > 0)
+                        return 0;
+
+                /* -ENODEV could be transient.  Ignore -ENODEV if link
+                 * is online.  Also, some SATA devices take a long
+                 * time to clear 0xff after reset.  For example,
+                 * HHD424020F7SV00 iVDR needs >= 800ms while Quantum
+                 * GoVault needs even more than that.  Wait for
+                 * ATA_TMOUT_FF_WAIT on -ENODEV if link isn't offline.
+                 *
+                 * Note that some PATA controllers (pata_ali) explode
+                 * if status register is read more than once when
+                 * there's no device attached.
+                 */
+                if (ready == -ENODEV) {
+                        if (ata_link_online(link))
+                                ready = 0;
+                        else if ((link->ap->flags & ATA_FLAG_SATA) &&
+                                 !ata_link_offline(link) &&
+                                 time_before(now, nodev_deadline))
+                                ready = 0;
+                }
+
+                if (ready)
+                        return ready;
+                if (time_after(now, deadline))
+                        return -EBUSY;
+
+                if (!warned && time_after(now, start + 5 * HZ) &&
+                    (deadline - now > 3 * HZ)) {
+                        ata_link_printk(link, KERN_WARNING,
+                                "link is slow to respond, please be patient "
+                                "(ready=%d)\n", tmp);
+                        warned = 1;
+                }
+
+                msleep(50);
+        }
+}
+
+/**
+ *      ata_wait_after_reset - wait for link to become ready after reset
+ *      @link: link to be waited on
+ *      @deadline: deadline jiffies for the operation
+ *      @check_ready: callback to check link readiness
+ *
+ *      Wait for @link to become ready after reset.
+ *
+ *      LOCKING:
+ *      EH context.
+ *
+ *      RETURNS:
+ *      0 if @linke is ready before @deadline; otherwise, -errno.
+ */
+extern int ata_wait_after_reset(struct ata_link *link, unsigned long deadline,
+                                int (*check_ready)(struct ata_link *link))
+{
+        msleep(ATA_WAIT_AFTER_RESET_MSECS);
+
+        return ata_wait_ready(link, deadline, check_ready);
+}
+
+/**
  *      sata_link_debounce - debounce SATA phy status
  *      @link: ATA link to debounce SATA phy status for
  *      @params: timing parameters { interval, duratinon, timeout } in msec
@@ -6075,6 +6172,7 @@ EXPORT_SYMBOL_GPL(ata_noop_qc_prep);
 EXPORT_SYMBOL_GPL(ata_port_probe);
 EXPORT_SYMBOL_GPL(ata_dev_disable);
 EXPORT_SYMBOL_GPL(sata_set_spd);
+EXPORT_SYMBOL_GPL(ata_wait_after_reset);
 EXPORT_SYMBOL_GPL(sata_link_debounce);
 EXPORT_SYMBOL_GPL(sata_link_resume);
 EXPORT_SYMBOL_GPL(ata_std_prereset);