Re: [PATCH 4/8] libata: separate out sil24_poll_register()

[Jeff Garzik <jgarzik@pobox.com>]

Tejun Heo wrote:
> This will be used by later patches.
> 
> Signed-off-by: Tejun Heo <htejun@gmail.com>
> 
> ---
> 
>  drivers/scsi/sata_sil24.c |   34 +++++++++++++++++++++++-----------
>  1 files changed, 23 insertions(+), 11 deletions(-)
> 
> dbf21a7fbc3fe926671416fecebfea70aef78c8a
> diff --git a/drivers/scsi/sata_sil24.c b/drivers/scsi/sata_sil24.c
> index 86233ac..0941f74 100644
> --- a/drivers/scsi/sata_sil24.c
> +++ b/drivers/scsi/sata_sil24.c
> @@ -431,6 +431,24 @@ static void sil24_tf_read(struct ata_por
>  	*tf = pp->tf;
>  }
>  
> +static int sil24_poll_register(void __iomem *reg, u32 mask, u32 val,
> +			       unsigned long interval_msec,
> +			       unsigned long timeout_msec)
> +{
> +	unsigned long timeout;
> +	u32 tmp;
> +
> +	timeout = jiffies + (timeout_msec * HZ) / 1000;
> +	do {
> +		tmp = readl(reg);
> +		if ((tmp & mask) == val)
> +			return 0;
> +		msleep(interval_msec);
> +	} while (time_before(jiffies, timeout));
> +

Let's not duplicate code in AHCI.  Initially the common code could live 
in libata, but let's think about the best place in the kernel for this 
function to live.