[PATCH] libata: always use polling IDENTIFY

libata switched to IRQ-driven IDENTIFY when IRQ-driven PIO was
introduced.  This has caused a lot of problems including device
misdetection and phantom device.

ATA_FLAG_DETECT_POLLING was added recently to selectively use polling
IDENTIFY on problemetic drivers but many controllers and devices are
affected by this problem and trying to adding ATA_FLAG_DETECT_POLLING
for each such case is diffcult and not very rewarding.

This patch makes libata always use polling IDENTIFY.  This is
consistent with libata's original behavior and drivers/ide's behavior.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

diff --git a/drivers/ata/ata_piix.c b/drivers/ata/ata_piix.c
index 788a269..a2d84f7 100644 (file)
--- a/drivers/ata/ata_piix.c
+++ b/drivers/ata/ata_piix.c
@@ -105,9 +105,8 @@ enum {
        PIIX_FLAG_AHCI          = (1 << 27), /* AHCI possible */
        PIIX_FLAG_CHECKINTR     = (1 << 28), /* make sure PCI INTx enabled */
 
-       PIIX_PATA_FLAGS         = ATA_FLAG_SLAVE_POSS | ATA_FLAG_DETECT_POLLING,
-       PIIX_SATA_FLAGS         = ATA_FLAG_SATA | PIIX_FLAG_CHECKINTR |
-                                 ATA_FLAG_DETECT_POLLING,
+       PIIX_PATA_FLAGS         = ATA_FLAG_SLAVE_POSS,
+       PIIX_SATA_FLAGS         = ATA_FLAG_SATA | PIIX_FLAG_CHECKINTR,
 
        /* combined mode.  if set, PATA is channel 0.
         * if clear, PATA is channel 1.

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 8832763..f8ec389 100644 (file)
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -1473,16 +1473,12 @@ int ata_dev_read_id(struct ata_device *dev, unsigned int *p_class,
        }
 
        tf.protocol = ATA_PROT_PIO;
-
-       /* presence detection using polling IDENTIFY? */
-       if (flags & ATA_READID_DETECT)
-               tf.flags |= ATA_TFLAG_POLLING;
+       tf.flags |= ATA_TFLAG_POLLING; /* for polling presence detection */
 
        err_mask = ata_exec_internal(dev, &tf, NULL, DMA_FROM_DEVICE,
                                     id, sizeof(id[0]) * ATA_ID_WORDS);
        if (err_mask) {
-               if ((flags & ATA_READID_DETECT) &&
-                   (err_mask & AC_ERR_NODEV_HINT)) {
+               if (err_mask & AC_ERR_NODEV_HINT) {
                        DPRINTK("ata%u.%d: NODEV after polling detection\n",
                                ap->id, dev->devno);
                        return -ENOENT;

diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index 2aad7b7..76a85df 100644 (file)
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -1692,9 +1692,6 @@ static int ata_eh_revalidate_and_attach(struct ata_port *ap,
                           ata_class_enabled(ehc->classes[dev->devno])) {
                        dev->class = ehc->classes[dev->devno];
 
-                       if (ap->flags & ATA_FLAG_DETECT_POLLING)
-                               readid_flags |= ATA_READID_DETECT;
-
                        rc = ata_dev_read_id(dev, &dev->class, readid_flags,
                                             dev->id);
                        if (rc == 0) {

diff --git a/drivers/ata/libata.h b/drivers/ata/libata.h
index 1ff3f59..107b2b5 100644 (file)
--- a/drivers/ata/libata.h
+++ b/drivers/ata/libata.h
@@ -42,8 +42,6 @@ struct ata_scsi_args {
 enum {
        /* flags for ata_dev_read_id() */
        ATA_READID_POSTRESET    = (1 << 0), /* reading ID after reset */
-       ATA_READID_DETECT       = (1 << 1), /* perform presence detection
-                                            * using polling IDENTIFY */
 };
 
 extern struct workqueue_struct *ata_aux_wq;

diff --git a/include/linux/libata.h b/include/linux/libata.h
index 8b57b6a..202283b 100644 (file)
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -176,9 +176,7 @@ enum {
        ATA_FLAG_SKIP_D2H_BSY   = (1 << 12), /* can't wait for the first D2H
                                              * Register FIS clearing BSY */
        ATA_FLAG_DEBUGMSG       = (1 << 13),
-       ATA_FLAG_DETECT_POLLING = (1 << 14), /* detect device presence by
-                                             * polling IDENTIFY */
-       ATA_FLAG_SETXFER_POLLING= (1 << 15), /* use polling for SETXFER */
+       ATA_FLAG_SETXFER_POLLING= (1 << 14), /* use polling for SETXFER */
 
        /* The following flag belongs to ap->pflags but is kept in
         * ap->flags because it's referenced in many LLDs and will be