1 files changed, 33 insertions, 15 deletions

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 3011919f3ec8..004dae4ea5bc 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -3048,6 +3048,8 @@ int ata_down_xfermask_limit(struct ata_device *dev, unsigned int sel)
 static int ata_dev_set_mode(struct ata_device *dev)
 {
         struct ata_eh_context *ehc = &dev->link->eh_context;
+        const char *dev_err_whine = "";
+        int ign_dev_err = 0;
         unsigned int err_mask;
         int rc;
 
@@ -3057,41 +3059,57 @@ static int ata_dev_set_mode(struct ata_device *dev)
 
         err_mask = ata_dev_set_xfermode(dev);
 
+        if (err_mask & ~AC_ERR_DEV)
+                goto fail;
+
+        /* revalidate */
+        ehc->i.flags |= ATA_EHI_POST_SETMODE;
+        rc = ata_dev_revalidate(dev, ATA_DEV_UNKNOWN, 0);
+        ehc->i.flags &= ~ATA_EHI_POST_SETMODE;
+        if (rc)
+                return rc;
+
         /* Old CFA may refuse this command, which is just fine */
         if (dev->xfer_shift == ATA_SHIFT_PIO && ata_id_is_cfa(dev->id))
-                err_mask &= ~AC_ERR_DEV;
+                ign_dev_err = 1;
 
         /* Some very old devices and some bad newer ones fail any kind of
            SET_XFERMODE request but support PIO0-2 timings and no IORDY */
         if (dev->xfer_shift == ATA_SHIFT_PIO && !ata_id_has_iordy(dev->id) &&
                         dev->pio_mode <= XFER_PIO_2)
-                err_mask &= ~AC_ERR_DEV;
+                ign_dev_err = 1;
 
         /* Early MWDMA devices do DMA but don't allow DMA mode setting.
            Don't fail an MWDMA0 set IFF the device indicates it is in MWDMA0 */
         if (dev->xfer_shift == ATA_SHIFT_MWDMA &&
             dev->dma_mode == XFER_MW_DMA_0 &&
             (dev->id[63] >> 8) & 1)
-                err_mask &= ~AC_ERR_DEV;
+                ign_dev_err = 1;
 
-        if (err_mask) {
-                ata_dev_printk(dev, KERN_ERR, "failed to set xfermode "
-                               "(err_mask=0x%x)\n", err_mask);
-                return -EIO;
-        }
+        /* if the device is actually configured correctly, ignore dev err */
+        if (dev->xfer_mode == ata_xfer_mask2mode(ata_id_xfermask(dev->id)))
+                ign_dev_err = 1;
 
-        ehc->i.flags |= ATA_EHI_POST_SETMODE;
-        rc = ata_dev_revalidate(dev, ATA_DEV_UNKNOWN, 0);
-        ehc->i.flags &= ~ATA_EHI_POST_SETMODE;
-        if (rc)
-                return rc;
+        if (err_mask & AC_ERR_DEV) {
+                if (!ign_dev_err)
+                        goto fail;
+                else
+                        dev_err_whine = " (device error ignored)";
+        }
 
         DPRINTK("xfer_shift=%u, xfer_mode=0x%x\n",
                 dev->xfer_shift, (int)dev->xfer_mode);
 
-        ata_dev_printk(dev, KERN_INFO, "configured for %s\n",
-                       ata_mode_string(ata_xfer_mode2mask(dev->xfer_mode)));
+        ata_dev_printk(dev, KERN_INFO, "configured for %s%s\n",
+                       ata_mode_string(ata_xfer_mode2mask(dev->xfer_mode)),
+                       dev_err_whine);
+
         return 0;
+
+ fail:
+        ata_dev_printk(dev, KERN_ERR, "failed to set xfermode "
+                       "(err_mask=0x%x)\n", err_mask);
+        return -EIO;
 }
 
 /**