diff options
Diffstat (limited to 'Documentation/DocBook')
| -rw-r--r-- | Documentation/DocBook/libata.tmpl | 104 |
1 files changed, 80 insertions, 24 deletions
diff --git a/Documentation/DocBook/libata.tmpl b/Documentation/DocBook/libata.tmpl index f869b03929d..e97c3231454 100644 --- a/Documentation/DocBook/libata.tmpl +++ b/Documentation/DocBook/libata.tmpl @@ -169,6 +169,22 @@ void (*tf_read) (struct ata_port *ap, struct ata_taskfile *tf); </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); @@ -204,11 +220,10 @@ command. <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/Error ATA shadow register from + Reads the Status/AltStatus 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 @@ -269,23 +284,6 @@ void (*set_mode) (struct ata_port *ap); </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); @@ -354,16 +352,74 @@ int (*qc_issue) (struct ata_queued_cmd *qc); </sect2> - <sect2><title>Timeout (error) handling</title> + <sect2><title>Exception and probe handling (EH)</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> -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> </sect2> |