libata: Add special ata_pio_need_iordy() handling for Compact Flash.

According to the Compact Flash specification r4.1, PIO modes 5 and 6
do not use iordy.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 9ae5835..175df54 100644 (file)
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -2001,6 +2001,10 @@ unsigned int ata_pio_need_iordy(const struct ata_device *adev)
           as the caller should know this */
        if (adev->link->ap->flags & ATA_FLAG_NO_IORDY)
                return 0;
+       /* CF spec. r4.1 Table 22 says no iordy on PIO5 and PIO6.  */
+       if (ata_id_is_cfa(adev->id)
+           && (adev->pio_mode == XFER_PIO_5 || adev->pio_mode == XFER_PIO_6))
+               return 0;
        /* PIO3 and higher it is mandatory */
        if (adev->pio_mode > XFER_PIO_2)
                return 1;