Commit 03c0e84f authored by Sergey Shtylyov's avatar Sergey Shtylyov Committed by Damien Le Moal
Browse files

ata: libata-sff: refactor ata_sff_altstatus() 



The driver's calls to ata_sff_altstatus() are mostly surrounded by some
clumsy checks. Refactor ata_sff_altstatus() to include the repetitive
checks and return a 'bool' result indicating if the alternate status
register exists or not.

While at it, further update the 'kernel-doc' comment -- the alternate
status register has never been a part of the taskfile, despite what
Jeff and co. think! :-)

In ata_sff_lost_interrupt(), wrap the ata_sff_altstatus() call in a
WARN_ON_ONCE() check to issue a warning if the device control register
does not exist. And while at it, fix the strange argument indentation
in the ata_port_warn() call following the call to ata_sff_altstatus().

Signed-off-by: default avatarSergey Shtylyov <s.shtylyov@omp.ru>
Signed-off-by: default avatarDamien Le Moal <damien.lemoal@opensource.wdc.com>
parent 4fc5f0aa

drivers/ata/libata-sff.c

+33 −26
Original line number Diff line number Diff line
@@ -70,22 +70,35 @@ EXPORT_SYMBOL_GPL(ata_sff_check_status); 
/**

 *	ata_sff_altstatus - Read device alternate status reg

 *	@ap: port where the device is

 *	@status: pointer to a status value

 *

 *	Reads ATA taskfile alternate status register for

 *	currently-selected device and return its value.

 *	Reads ATA alternate status register for currently-selected device

 *	and return its value.

 *

 *	Note: may NOT be used as the check_altstatus() entry in

 *	ata_port_operations.

 *	RETURN:

 *	true if the register exists, false if not.

 *

 *	LOCKING:

 *	Inherited from caller.

 */

static u8 ata_sff_altstatus(struct ata_port *ap)

static bool ata_sff_altstatus(struct ata_port *ap, u8 *status)

{

	if (ap->ops->sff_check_altstatus)

		return ap->ops->sff_check_altstatus(ap);

	u8 tmp;



	if (ap->ops->sff_check_altstatus) {

		tmp = ap->ops->sff_check_altstatus(ap);

		goto read;

	}

	if (ap->ioaddr.altstatus_addr) {

		tmp = ioread8(ap->ioaddr.altstatus_addr);

		goto read;

	}

	return false;



	return ioread8(ap->ioaddr.altstatus_addr);

read:

	if (status)

		*status = tmp;

	return true;

}



/**
@@ -104,12 +117,9 @@ static u8 ata_sff_irq_status(struct ata_port *ap) 
{

	u8 status;



	if (ap->ops->sff_check_altstatus || ap->ioaddr.altstatus_addr) {

		status = ata_sff_altstatus(ap);

	/* Not us: We are busy */

		if (status & ATA_BUSY)

	if (ata_sff_altstatus(ap, &status) && (status & ATA_BUSY))

		return status;

	}

	/* Clear INTRQ latch */

	status = ap->ops->sff_check_status(ap);

	return status;
@@ -129,10 +139,7 @@ static u8 ata_sff_irq_status(struct ata_port *ap) 


static void ata_sff_sync(struct ata_port *ap)

{

	if (ap->ops->sff_check_altstatus)

		ap->ops->sff_check_altstatus(ap);

	else if (ap->ioaddr.altstatus_addr)

		ioread8(ap->ioaddr.altstatus_addr);

	ata_sff_altstatus(ap, NULL);

}



/**
@@ -164,12 +171,12 @@ EXPORT_SYMBOL_GPL(ata_sff_pause); 


void ata_sff_dma_pause(struct ata_port *ap)

{

	if (ap->ops->sff_check_altstatus || ap->ioaddr.altstatus_addr) {

		/* An altstatus read will cause the needed delay without

		   messing up the IRQ status */

		ata_sff_altstatus(ap);

	/*

	 * An altstatus read will cause the needed delay without

	 * messing up the IRQ status

	 */

	if (ata_sff_altstatus(ap, NULL))

		return;

	}

	/* There are no DMA controllers without ctl. BUG here to ensure

	   we never violate the HDMA1:0 transition timing and risk

	   corruption. */
@@ -1637,14 +1644,14 @@ void ata_sff_lost_interrupt(struct ata_port *ap) 
		return;

	/* See if the controller thinks it is still busy - if so the command

	   isn't a lost IRQ but is still in progress */

	status = ata_sff_altstatus(ap);

	if (WARN_ON_ONCE(!ata_sff_altstatus(ap, &status)))

		return;

	if (status & ATA_BUSY)

		return;



	/* There was a command running, we are no longer busy and we have

	   no interrupt. */

	ata_port_warn(ap, "lost interrupt (Status 0x%x)\n",

								status);

	ata_port_warn(ap, "lost interrupt (Status 0x%x)\n", status);

	/* Run the host interrupt logic as if the interrupt had not been

	   lost */

	ata_sff_port_intr(ap, qc);