Re: [PATCH 1/2] libata: Support PIO polling-only hosts.

Alan Cox
2007-11-07T13:09:58Z

On Wed, 7 Nov 2007 17:10:52 +0900
Paul Mundt <lethal@linux-sh.org> wrote:

> By default ata_host_activate() expects a valid IRQ in order to
> successfully register the host. This patch enables a special case
> for registering polling-only hosts that either don't have IRQs
> or have buggy IRQ generation (either in terms of handling or
> sensing), which otherwise work fine.
>
> Hosts that want to use polling mode can simply set ATA_FLAG_PIO_POLLING
> and pass in a NULL IRQ handler or invalid (< 0) IRQ.

NAK

Zero is "no IRQ", please use that for polling not "< 0"

> + * A NULL @irq_handler or invalid IRQ skips the IRQ registration
> + * and expects the host to have set polling mode on the port.
> + *

There is no need to llow NULL irq_handler as a different case here. Any
caller can provide (NULL, 0). If anything you might want to warn if they
provide IRQ 0, and a handler