[PATCH/RFC 0/4] libata: more irq driven pio follow-up patches

[Albert Lee <albertcc@tw.ibm.com>]

Dear all,

More irq driven PIO follow-up patches per Jeff's advice:
 1. merge ata_dataout_task and ata_pio_task
 2. add read/write multiple support

patch 1/4: move functions
    - move atapi_send_cdb() and ata_dataout_task() to be near 
ata_pio_*() functions

patch 2/4: remove ap->dataout_task
    - remove ap->dataout_task
    - let ata_pio_task() handle the HSM_ST_FIRST state.
    - rename ata_dataout_task() to ata_pio_first_block()

patch 3/4: integrate ata_pio_first_block() with ata_pio_task()
    - change the return value of ata_pio_complete()
    - add return value for ata_pio_first_block()
    - rename variable "qc_completed" to "has_next" in ata_pio_task()

patch 4/4: add read/write multiple support
    - add ATA_CMD_READ_MULTI, etc. to ata.h
    - add multi_count to ata_device and initialize it with device 
identify data
    - merge ata_prot_to_cmd() with ata_dev_set_protocol()
    - ata_pio_complete(): change the wait condition from (ATA_BUSY | 
ATA_DRQ) to ATA_BUSY
    - add ata_pio_sectors() to support r/w multiple commands
    - ata_pio_block(): add ata_altstatus(ap) to prevent reading device 
status before it is valid

Patch against libata-dev irq-pio branch 
(54f00389563c80fa1de250a21256313ba01ca07d).

For your review and advice, thanks.

Albert