libata: more doc updates

Document recently-added ata_port_operations hooks.

Fill several doc stubs in libata-core.c.

1 files changed, 44 insertions, 13 deletions

diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index 63d3f70d06e1..4d707d06a5d1 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -1241,10 +1241,14 @@ void ata_port_probe(struct ata_port *ap)
 }
 
 /**
- *      __sata_phy_reset -
- *      @ap:
+ *      __sata_phy_reset - Wake/reset a low-level SATA PHY
+ *      @ap: SATA port associated with target SATA PHY.
  *
- *      LOCKING:
+ *      This function issues commands to standard SATA Sxxx
+ *      PHY registers, to wake up the phy (and device), and
+ *      clear any reset condition.
+ *
+ *      LOCKING: None.  Serialized during ata_bus_probe().
  *
  */
 void __sata_phy_reset(struct ata_port *ap)
@@ -1289,10 +1293,13 @@ void __sata_phy_reset(struct ata_port *ap)
 }
 
 /**
- *      __sata_phy_reset -
- *      @ap:
+ *      sata_phy_reset - Reset SATA bus.
+ *      @ap: SATA port associated with target SATA PHY.
  *
- *      LOCKING:
+ *      This function resets the SATA bus, and then probes
+ *      the bus for devices.
+ *
+ *      LOCKING: None.  Serialized during ata_bus_probe().
  *
  */
 void sata_phy_reset(struct ata_port *ap)
@@ -1304,10 +1311,16 @@ void sata_phy_reset(struct ata_port *ap)
 }
 
 /**
- *      ata_port_disable -
- *      @ap:
+ *      ata_port_disable - Disable port.
+ *      @ap: Port to be disabled.
  *
- *      LOCKING:
+ *      Modify @ap data structure such that the system
+ *      thinks that the entire port is disabled, and should
+ *      never attempt to probe or communicate with devices
+ *      on this port.
+ *
+ *      LOCKING: host_set lock, or some other form of
+ *      serialization.
  */
 
 void ata_port_disable(struct ata_port *ap)
@@ -1416,7 +1429,9 @@ static void ata_host_set_dma(struct ata_port *ap, u8 xfer_mode,
  *      ata_set_mode - Program timings and issue SET FEATURES - XFER
  *      @ap: port on which timings will be programmed
  *
- *      LOCKING:
+ *      Set ATA device disk transfer mode (PIO3, UDMA6, etc.).
+ *
+ *      LOCKING: None.  Serialized during ata_bus_probe().
  *
  */
 static void ata_set_mode(struct ata_port *ap)
@@ -1467,7 +1482,10 @@ err_out:
  *      @tmout_pat: impatience timeout
  *      @tmout: overall timeout
  *
- *      LOCKING:
+ *      Sleep until ATA Status register bit BSY clears,
+ *      or a timeout occurs.
+ *
+ *      LOCKING: None.
  *
  */
 
@@ -1556,7 +1574,7 @@ static void ata_bus_post_reset(struct ata_port *ap, unsigned int devmask)
  *      ata_bus_edd -
  *      @ap:
  *
- *      LOCKING:
+ *      LOCKING: None.  Serialized during ata_bus_probe().
  *
  */
 
@@ -1909,7 +1927,10 @@ static int ata_choose_xfer_mode(struct ata_port *ap,
  *      @ap: Port associated with device @dev
  *      @dev: Device to which command will be sent
  *
- *      LOCKING:
+ *      Issue SET FEATURES - XFER MODE command to device @dev
+ *      on port @ap.
+ *
+ *      LOCKING: None.  Serialized during ata_bus_probe().
  */
 
 static void ata_dev_set_xfermode(struct ata_port *ap, struct ata_device *dev)
@@ -1981,7 +2002,11 @@ static void ata_sg_clean(struct ata_queued_cmd *qc)
  *      ata_fill_sg - Fill PCI IDE PRD table
  *      @qc: Metadata associated with taskfile to be transferred
  *
+ *      Fill PCI IDE PRD (scatter-gather) table with segments
+ *      associated with the current disk command.
+ *
  *      LOCKING:
+ *      spin_lock_irqsave(host_set lock)
  *
  */
 static void ata_fill_sg(struct ata_queued_cmd *qc)
@@ -2028,6 +2053,10 @@ static void ata_fill_sg(struct ata_queued_cmd *qc)
  *      ata_check_atapi_dma - Check whether ATAPI DMA can be supported
  *      @qc: Metadata associated with taskfile to check
  *
+ *      Allow low-level driver to filter ATA PACKET commands, returning
+ *      a status indicating whether or not it is OK to use DMA for the
+ *      supplied PACKET command.
+ *
  *      LOCKING:
  *      RETURNS: 0 when ATAPI DMA can be used
  *               nonzero otherwise
@@ -2046,6 +2075,8 @@ int ata_check_atapi_dma(struct ata_queued_cmd *qc)
  *      ata_qc_prep - Prepare taskfile for submission
  *      @qc: Metadata associated with taskfile to be prepared
  *
+ *      Prepare ATA taskfile for submission.
+ *
  *      LOCKING:
  *      spin_lock_irqsave(host_set lock)
  */