</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>
<programlisting>
void (*exec_command)(struct ata_port *ap, struct ata_taskfile *tf);
<programlisting>
u8 (*check_status)(struct ata_port *ap);
u8 (*check_altstatus)(struct ata_port *ap);
+u8 (*check_err)(struct ata_port *ap);
</programlisting>
<para>
- Reads the Status/AltStatus ATA shadow register from
+ Reads the Status/AltStatus/Error ATA shadow register from
hardware. On some hardware, reading the Status register has
the side effect of clearing the interrupt condition.
Most drivers for taskfile-based hardware use
</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>
<programlisting>
void (*bmdma_setup) (struct ata_queued_cmd *qc);
</sect2>
- <sect2><title>Exception and probe handling (EH)</title>
+ <sect2><title>Timeout (error) handling</title>
<programlisting>
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>
<para>
-Perform any hardware-specific actions necessary to finish processing
-after executing a probe-time or EH-time command via ata_exec_internal().
+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().
</para>
</sect2>