ATA_WAIT_REGISTER(9)                      libata Library                     ATA_WAIT_REGISTER(9)



NAME
       ata_wait_register - wait until register value changes

SYNOPSIS
       u32 ata_wait_register(struct ata_port * ap, void __iomem * reg, u32 mask, u32 val,
                             unsigned long interval, unsigned long timeout);

ARGUMENTS
       ap
           ATA port to wait register for, can be NULL

       reg
           IO-mapped register

       mask
           Mask to apply to read register value

       val
           Wait condition

       interval
           polling interval in milliseconds

       timeout
           timeout in milliseconds

DESCRIPTION
       Waiting for some bits of register to change is a common operation for ATA controllers.
       This function reads 32bit LE IO-mapped register reg and tests for the following condition.

       (*reg & mask) != val

       If the condition is met, it returns; otherwise, the process is repeated after
       interval_msec until timeout.

       LOCKING: Kernel thread context (may sleep)

RETURN
       The final register value.

AUTHOR
       Jeff Garzik
           Author.

COPYRIGHT
Kernel Hackers Manual 4.8.                 January 2017                      ATA_WAIT_REGISTER(9)