pata_scc.c: small fixes (Workaround for errata A308)

This patch fixes some issues of the previous patch:
- Use mode_filter() hook to limit ATAPI UDMA mode
- "data loss" warning message
- handling of udma_mask

Signed-off-by: Kou Ishizaki <kou.ishizaki@toshiba.co.jp>
Signed-off-by: Akira Iguchi <akira2.iguchi@toshiba.co.jp>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 16 insertions, 11 deletions

diff --git a/drivers/ata/pata_scc.c b/drivers/ata/pata_scc.c
index c55667e0eb65..c0ffbed3e75d 100644
--- a/drivers/ata/pata_scc.c
+++ b/drivers/ata/pata_scc.c
@@ -238,12 +238,6 @@ static void scc_set_dmamode (struct ata_port *ap, struct ata_device *adev)
         else
                 offset = 0;     /* 100MHz */
 
-        /* errata A308 workaround: limit ATAPI UDMA mode to UDMA4 */
-        if (adev->class == ATA_DEV_ATAPI && speed > XFER_UDMA_4) {
-                printk(KERN_INFO "%s: limit ATAPI UDMA to UDMA4\n", DRV_NAME);
-                speed = XFER_UDMA_4;
-        }
-
         if (speed >= XFER_UDMA_0)
                 idx = speed - XFER_UDMA_0;
         else
@@ -264,6 +258,17 @@ static void scc_set_dmamode (struct ata_port *ap, struct ata_device *adev)
                  JCTSStbl[offset][idx] << 16 | JCENVTtbl[offset][idx]);
 }
 
+unsigned long scc_mode_filter(struct ata_device *adev, unsigned long mask)
+{
+        /* errata A308 workaround: limit ATAPI UDMA mode to UDMA4 */
+        if (adev->class == ATA_DEV_ATAPI &&
+            (mask & (0xE0 << ATA_SHIFT_UDMA))) {
+                printk(KERN_INFO "%s: limit ATAPI UDMA to UDMA4\n", DRV_NAME);
+                mask &= ~(0xE0 << ATA_SHIFT_UDMA);
+        }
+        return ata_pci_default_filter(adev, mask);
+}
+
 /**
  *      scc_tf_load - send taskfile registers to host controller
  *      @ap: Port to which output is sent
@@ -741,7 +746,7 @@ static u8 scc_bmdma_status (struct ata_port *ap)
                 return host_stat;
 
         /* errata A252,A308 workaround: Step4 */
-        if (ata_altstatus(ap) & ATA_ERR && int_status & INTSTS_INTRQ)
+        if ((ata_altstatus(ap) & ATA_ERR) && (int_status & INTSTS_INTRQ))
                 return (host_stat | ATA_DMA_INTR);
 
         /* errata A308 workaround Step5 */
@@ -752,11 +757,11 @@ static u8 scc_bmdma_status (struct ata_port *ap)
                 if ((qc->tf.protocol == ATA_PROT_DMA &&
                      qc->dev->xfer_mode > XFER_UDMA_4)) {
                         if (!(int_status & INTSTS_ACTEINT)) {
-                                printk(KERN_WARNING "ata%u: data lost occurred. (ACTEINT==0, retry:%d)\n",
-                                       ap->print_id, retry);
+                                printk(KERN_WARNING "ata%u: operation failed (transfer data loss)\n",
+                                       ap->print_id);
                                 host_stat |= ATA_DMA_ERR;
                                 if (retry++)
-                                        ap->udma_mask >>= 1;
+                                        ap->udma_mask &= ~(1 << qc->dev->xfer_mode);
                         } else
                                 retry = 0;
                 }
@@ -1016,7 +1021,7 @@ static const struct ata_port_operations scc_pata_ops = {
         .port_disable           = ata_port_disable,
         .set_piomode            = scc_set_piomode,
         .set_dmamode            = scc_set_dmamode,
-        .mode_filter            = ata_pci_default_filter,
+        .mode_filter            = scc_mode_filter,
 
         .tf_load                = scc_tf_load,
         .tf_read                = scc_tf_read,