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[libata] Update docs to reflect current driver API

Jeff Garzik 19 年之前
父节点
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bf717b11ae
共有 2 个文件被更改,包括 81 次插入25 次删除
  1. 80 24
      Documentation/DocBook/libata.tmpl
  2. 1 1
      drivers/scsi/libata-core.c

+ 80 - 24
Documentation/DocBook/libata.tmpl

@@ -169,6 +169,22 @@ void (*tf_read) (struct ata_port *ap, struct ata_taskfile *tf);
 
 
 	</sect2>
 	</sect2>
 
 
+	<sect2><title>PIO data read/write</title>
+	<programlisting>
+void (*data_xfer) (struct ata_device *, unsigned char *, unsigned int, int);
+	</programlisting>
+
+	<para>
+All bmdma-style drivers must implement this hook.  This is the low-level
+operation that actually copies the data bytes during a PIO data
+transfer.
+Typically the driver
+will choose one of ata_pio_data_xfer_noirq(), ata_pio_data_xfer(), or
+ata_mmio_data_xfer().
+	</para>
+
+	</sect2>
+
 	<sect2><title>ATA command execute</title>
 	<sect2><title>ATA command execute</title>
 	<programlisting>
 	<programlisting>
 void (*exec_command)(struct ata_port *ap, struct ata_taskfile *tf);
 void (*exec_command)(struct ata_port *ap, struct ata_taskfile *tf);
@@ -204,11 +220,10 @@ command.
 	<programlisting>
 	<programlisting>
 u8   (*check_status)(struct ata_port *ap);
 u8   (*check_status)(struct ata_port *ap);
 u8   (*check_altstatus)(struct ata_port *ap);
 u8   (*check_altstatus)(struct ata_port *ap);
-u8   (*check_err)(struct ata_port *ap);
 	</programlisting>
 	</programlisting>
 
 
 	<para>
 	<para>
-	Reads the Status/AltStatus/Error ATA shadow register from
+	Reads the Status/AltStatus ATA shadow register from
 	hardware.  On some hardware, reading the Status register has
 	hardware.  On some hardware, reading the Status register has
 	the side effect of clearing the interrupt condition.
 	the side effect of clearing the interrupt condition.
 	Most drivers for taskfile-based hardware use
 	Most drivers for taskfile-based hardware use
@@ -269,23 +284,6 @@ void (*set_mode) (struct ata_port *ap);
 
 
 	</sect2>
 	</sect2>
 
 
-	<sect2><title>Reset ATA bus</title>
-	<programlisting>
-void (*phy_reset) (struct ata_port *ap);
-	</programlisting>
-
-	<para>
-	The very first step in the probe phase.  Actions vary depending
-	on the bus type, typically.  After waking up the device and probing
-	for device presence (PATA and SATA), typically a soft reset
-	(SRST) will be performed.  Drivers typically use the helper
-	functions ata_bus_reset() or sata_phy_reset() for this hook.
-	Many SATA drivers use sata_phy_reset() or call it from within
-	their own phy_reset() functions.
-	</para>
-
-	</sect2>
-
 	<sect2><title>Control PCI IDE BMDMA engine</title>
 	<sect2><title>Control PCI IDE BMDMA engine</title>
 	<programlisting>
 	<programlisting>
 void (*bmdma_setup) (struct ata_queued_cmd *qc);
 void (*bmdma_setup) (struct ata_queued_cmd *qc);
@@ -354,16 +352,74 @@ int (*qc_issue) (struct ata_queued_cmd *qc);
 
 
 	</sect2>
 	</sect2>
 
 
-	<sect2><title>Timeout (error) handling</title>
+	<sect2><title>Exception and probe handling (EH)</title>
 	<programlisting>
 	<programlisting>
 void (*eng_timeout) (struct ata_port *ap);
 void (*eng_timeout) (struct ata_port *ap);
+void (*phy_reset) (struct ata_port *ap);
+	</programlisting>
+
+	<para>
+Deprecated.  Use ->error_handler() instead.
+	</para>
+
+	<programlisting>
+void (*freeze) (struct ata_port *ap);
+void (*thaw) (struct ata_port *ap);
+	</programlisting>
+
+	<para>
+ata_port_freeze() is called when HSM violations or some other
+condition disrupts normal operation of the port.  A frozen port
+is not allowed to perform any operation until the port is
+thawed, which usually follows a successful reset.
+	</para>
+
+	<para>
+The optional ->freeze() callback can be used for freezing the port
+hardware-wise (e.g. mask interrupt and stop DMA engine).  If a
+port cannot be frozen hardware-wise, the interrupt handler
+must ack and clear interrupts unconditionally while the port
+is frozen.
+	</para>
+	<para>
+The optional ->thaw() callback is called to perform the opposite of ->freeze():
+prepare the port for normal operation once again.  Unmask interrupts,
+start DMA engine, etc.
+	</para>
+
+	<programlisting>
+void (*error_handler) (struct ata_port *ap);
+	</programlisting>
+
+	<para>
+->error_handler() is a driver's hook into probe, hotplug, and recovery
+and other exceptional conditions.  The primary responsibility of an
+implementation is to call ata_do_eh() or ata_bmdma_drive_eh() with a set
+of EH hooks as arguments:
+	</para>
+
+	<para>
+'prereset' hook (may be NULL) is called during an EH reset, before any other actions
+are taken.
+	</para>
+
+	<para>
+'postreset' hook (may be NULL) is called after the EH reset is performed.  Based on
+existing conditions, severity of the problem, and hardware capabilities,
+	</para>
+
+	<para>
+Either 'softreset' (may be NULL) or 'hardreset' (may be NULL) will be
+called to perform the low-level EH reset.
+	</para>
+
+	<programlisting>
+void (*post_internal_cmd) (struct ata_queued_cmd *qc);
 	</programlisting>
 	</programlisting>
 
 
 	<para>
 	<para>
-This is a high level error handling function, called from the
-error handling thread, when a command times out.  Most newer
-hardware will implement its own error handling code here.  IDE BMDMA
-drivers may use the helper function ata_eng_timeout().
+Perform any hardware-specific actions necessary to finish processing
+after executing a probe-time or EH-time command via ata_exec_internal().
 	</para>
 	</para>
 
 
 	</sect2>
 	</sect2>

+ 1 - 1
drivers/scsi/libata-core.c

@@ -3496,7 +3496,7 @@ void swap_buf_le16(u16 *buf, unsigned int buf_words)
 
 
 /**
 /**
  *	ata_mmio_data_xfer - Transfer data by MMIO
  *	ata_mmio_data_xfer - Transfer data by MMIO
- *	@dev: device for this I/O
+ *	@adev: device for this I/O
  *	@buf: data buffer
  *	@buf: data buffer
  *	@buflen: buffer length
  *	@buflen: buffer length
  *	@write_data: read/write
  *	@write_data: read/write