libata: Handle drives that require a spin-up command before first access
(S)ATA drives can be configured for "power-up in standby",
a mode whereby a specific "spin up now!" command is required
before the first media access.
Currently, a drive with this feature enabled can not be used at all
with libata, and once in this mode, the drive becomes a doorstop.
The older drivers/ide subsystem at least enumerates the drive,
so that it can be woken up after the fact from a userspace HDIO_*
command, but not libata.
This patch adds support to libata for the "power-up in standby"
mode where a "spin up now!" command (SET_FEATURES) is needed.
With this, libata will recognize such drives, spin them up,
and then re-IDENTIFY them if necessary to get a full/complete
set of drive features data.
Drives in this state are determined by looking for
special values in id[2], as documented in the current ATA specs.
Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 6d0a946..227399e 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -1649,13 +1649,13 @@
struct ata_taskfile tf;
unsigned int err_mask = 0;
const char *reason;
+ int tried_spinup = 0;
int rc;
if (ata_msg_ctl(ap))
ata_dev_printk(dev, KERN_DEBUG, "%s: ENTER\n", __FUNCTION__);
ata_dev_select(ap, dev->devno, 1, 1); /* select device 0/1 */
-
retry:
ata_tf_init(dev, &tf);
@@ -1712,6 +1712,32 @@
goto err_out;
}
+ if (!tried_spinup && (id[2] == 0x37c8 || id[2] == 0x738c)) {
+ tried_spinup = 1;
+ /*
+ * Drive powered-up in standby mode, and requires a specific
+ * SET_FEATURES spin-up subcommand before it will accept
+ * anything other than the original IDENTIFY command.
+ */
+ ata_tf_init(dev, &tf);
+ tf.command = ATA_CMD_SET_FEATURES;
+ tf.feature = SETFEATURES_SPINUP;
+ tf.protocol = ATA_PROT_NODATA;
+ tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
+ err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0);
+ if (err_mask) {
+ rc = -EIO;
+ reason = "SPINUP failed";
+ goto err_out;
+ }
+ /*
+ * If the drive initially returned incomplete IDENTIFY info,
+ * we now must reissue the IDENTIFY command.
+ */
+ if (id[2] == 0x37c8)
+ goto retry;
+ }
+
if ((flags & ATA_READID_POSTRESET) && class == ATA_DEV_ATA) {
/*
* The exact sequence expected by certain pre-ATA4 drives is: