ata: libata: remove deprecated EH callbacks

Now that all libata drivers have migrated to use the error_handler
callback, remove the deprecated phy_reset and eng_timeout callbacks.

Also remove references to non-existent functions sata_phy_reset and
ata_qc_timeout from Documentation/driver-api/libata.rst.

Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>

Author: Niklas Cassel

Documentation/driver-api/libata.rst

@@ -256,14 +256,6 @@ advanced drivers implement their own ``->qc_issue``.
 Exception and probe handling (EH)
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-::
-
-    void (*eng_timeout) (struct ata_port *ap);
-    void (*phy_reset) (struct ata_port *ap);
-
-
-Deprecated. Use ``->error_handler()`` instead.
-
 ::
 
     void (*freeze) (struct ata_port *ap);
@@ -348,8 +340,7 @@ SATA phy read/write
                        u32 val);
 
 
-Read and write standard SATA phy registers. Currently only used if
-``->phy_reset`` hook called the :c:func:`sata_phy_reset` helper function.
+Read and write standard SATA phy registers.
 sc_reg is one of SCR_STATUS, SCR_CONTROL, SCR_ERROR, or SCR_ACTIVE.
 
 Init and shutdown
@@ -520,13 +511,12 @@ to return without deallocating the qc. This leads us to
 
 :c:func:`ata_scsi_error` is the current ``transportt->eh_strategy_handler()``
 for libata. As discussed above, this will be entered in two cases -
-timeout and ATAPI error completion. This function calls low level libata
-driver's :c:func:`eng_timeout` callback, the standard callback for which is
-:c:func:`ata_eng_timeout`. It checks if a qc is active and calls
-:c:func:`ata_qc_timeout` on the qc if so. Actual error handling occurs in
-:c:func:`ata_qc_timeout`.
+timeout and ATAPI error completion. This function will check if a qc is active
+and has not failed yet. Such a qc will be marked with AC_ERR_TIMEOUT such that
+EH will know to handle it later. Then it calls low level libata driver's
+:c:func:`error_handler` callback.
 
-If EH is invoked for timeout, :c:func:`ata_qc_timeout` stops BMDMA and
+When the :c:func:`error_handler` callback is invoked it stops BMDMA and
 completes the qc. Note that as we're currently in EH, we cannot call
 scsi_done. As described in SCSI EH doc, a recovered scmd should be
 either retried with :c:func:`scsi_queue_insert` or finished with

drivers/ata/pata_sl82c105.c

@@ -180,8 +180,7 @@ static void sl82c105_bmdma_start(struct ata_queued_cmd *qc)
  *	document.
  *
  *	This function is also called to turn off DMA when a timeout occurs
- *	during DMA operation. In both cases we need to reset the engine,
- *	so no actual eng_timeout handler is required.
+ *	during DMA operation. In both cases we need to reset the engine.
  *
  *	We assume bmdma_stop is always called if bmdma_start as called. If
  *	not then we may need to wrap qc_issue.

include/linux/libata.h

@@ -975,12 +975,6 @@ struct ata_port_operations {
 	ssize_t (*transmit_led_message)(struct ata_port *ap, u32 state,
 					ssize_t size);
 
-	/*
-	 * Obsolete
-	 */
-	void (*phy_reset)(struct ata_port *ap);
-	void (*eng_timeout)(struct ata_port *ap);
-
 	/*
 	 * ->inherits must be the last field and all the preceding
 	 * fields must be pointers.