[libata] check for SATA async notify support

Check to see if an ATAPI device supports Asynchronous Notification.
If so, enable it, if the host controller supports AN.

Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 53 insertions, 0 deletions

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index c0f3c78a2be..9f87f7ddd48 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -70,6 +70,7 @@ const unsigned long sata_deb_timing_long[]		= { 100, 2000, 5000 };
 static unsigned int ata_dev_init_params(struct ata_device *dev,
                                         u16 heads, u16 sectors);
 static unsigned int ata_dev_set_xfermode(struct ata_device *dev);
+static unsigned int ata_dev_set_AN(struct ata_device *dev, u8 enable);
 static void ata_dev_xfermask(struct ata_device *dev);
 static unsigned long ata_dev_blacklisted(const struct ata_device *dev);
 
@@ -1987,6 +1988,22 @@ int ata_dev_configure(struct ata_device *dev)
                 }
                 dev->cdb_len = (unsigned int) rc;
 
+                /*
+                 * check to see if this ATAPI device supports
+                 * Asynchronous Notification
+                 */
+                if ((ap->flags & ATA_FLAG_AN) && ata_id_has_AN(id)) {
+                        int err;
+                        /* issue SET feature command to turn this on */
+                        err = ata_dev_set_AN(dev, SETFEATURES_SATA_ENABLE);
+                        if (err)
+                                ata_dev_printk(dev, KERN_ERR,
+                                                "unable to set AN, err %x\n",
+                                                err);
+                        else
+                                dev->flags |= ATA_DFLAG_AN;
+                }
+
                 if (ata_id_cdb_intr(dev->id)) {
                         dev->flags |= ATA_DFLAG_CDB_INTR;
                         cdb_intr_string = ", CDB intr";
@@ -3975,6 +3992,42 @@ static unsigned int ata_dev_set_xfermode(struct ata_device *dev)
 }
 
 /**
+ *      ata_dev_set_AN - Issue SET FEATURES - SATA FEATURES
+ *      @dev: Device to which command will be sent
+ *      @enable: Whether to enable or disable the feature
+ *
+ *      Issue SET FEATURES - SATA FEATURES command to device @dev
+ *      on port @ap with sector count set to indicate Asynchronous
+ *      Notification feature
+ *
+ *      LOCKING:
+ *      PCI/etc. bus probe sem.
+ *
+ *      RETURNS:
+ *      0 on success, AC_ERR_* mask otherwise.
+ */
+static unsigned int ata_dev_set_AN(struct ata_device *dev, u8 enable)
+{
+        struct ata_taskfile tf;
+        unsigned int err_mask;
+
+        /* set up set-features taskfile */
+        DPRINTK("set features - SATA features\n");
+
+        ata_tf_init(dev, &tf);
+        tf.command = ATA_CMD_SET_FEATURES;
+        tf.feature = enable;
+        tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
+        tf.protocol = ATA_PROT_NODATA;
+        tf.nsect = SATA_AN;
+
+        err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0);
+
+        DPRINTK("EXIT, err_mask=%x\n", err_mask);
+        return err_mask;
+}
+
+/**
  *      ata_dev_init_params - Issue INIT DEV PARAMS command
  *      @dev: Device to which command will be sent
  *      @heads: Number of heads (taskfile parameter)