diff options
Diffstat (limited to 'drivers/ata')
| -rw-r--r-- | drivers/ata/libata-core.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c index 25d8d3f778a..2cf8251728d 100644 --- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -1410,7 +1410,16 @@ int ata_dev_read_id(struct ata_device *dev, unsigned int *p_class, } tf.protocol = ATA_PROT_PIO; - tf.flags |= ATA_TFLAG_POLLING; /* for polling presence detection */ + + /* Some devices choke if TF registers contain garbage. Make + * sure those are properly initialized. + */ + tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE; + + /* Device presence detection is unreliable on some + * controllers. Always poll IDENTIFY if available. + */ + tf.flags |= ATA_TFLAG_POLLING; err_mask = ata_exec_internal(dev, &tf, NULL, DMA_FROM_DEVICE, id, sizeof(id[0]) * ATA_ID_WORDS); |