libata: implement and use ata_noop_irq_clear()

->irq_clear() is used to clear IRQ bit of a SFF controller and isn't
useful for drivers which don't use libata SFF HSM implementation.
However, it's a required callback and many drivers implement their own
noop version as placeholder.  This patch implements ata_noop_irq_clear
and use it to replace those custom placeholders.

Also, SFF drivers which don't support BMDMA don't need to use
ata_bmdma_irq_clear().  It becomes noop if BMDMA address isn't
initialized.  Convert them to use ata_noop_irq_clear().

Signed-off-by: Tejun Heo <htejun@gmail.com>

1 files changed, 3 insertions, 9 deletions

diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index 1bd258e5390f..492e521715d6 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -244,7 +244,6 @@ static int ahci_scr_read(struct ata_port *ap, unsigned int sc_reg, u32 *val);
 static int ahci_scr_write(struct ata_port *ap, unsigned int sc_reg, u32 val);
 static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent);
 static unsigned int ahci_qc_issue(struct ata_queued_cmd *qc);
-static void ahci_irq_clear(struct ata_port *ap);
 static int ahci_port_start(struct ata_port *ap);
 static void ahci_port_stop(struct ata_port *ap);
 static void ahci_tf_read(struct ata_port *ap, struct ata_taskfile *tf);
@@ -307,7 +306,7 @@ static const struct ata_port_operations ahci_ops = {
         .qc_prep                = ahci_qc_prep,
         .qc_issue               = ahci_qc_issue,
 
-        .irq_clear              = ahci_irq_clear,
+        .irq_clear              = ata_noop_irq_clear,
 
         .scr_read               = ahci_scr_read,
         .scr_write              = ahci_scr_write,
@@ -343,7 +342,7 @@ static const struct ata_port_operations ahci_vt8251_ops = {
         .qc_prep                = ahci_qc_prep,
         .qc_issue               = ahci_qc_issue,
 
-        .irq_clear              = ahci_irq_clear,
+        .irq_clear              = ata_noop_irq_clear,
 
         .scr_read               = ahci_scr_read,
         .scr_write              = ahci_scr_write,
@@ -377,7 +376,7 @@ static const struct ata_port_operations ahci_p5wdh_ops = {
         .qc_prep                = ahci_qc_prep,
         .qc_issue               = ahci_qc_issue,
 
-        .irq_clear              = ahci_irq_clear,
+        .irq_clear              = ata_noop_irq_clear,
 
         .scr_read               = ahci_scr_read,
         .scr_write              = ahci_scr_write,
@@ -1769,11 +1768,6 @@ static void ahci_port_intr(struct ata_port *ap)
         }
 }
 
-static void ahci_irq_clear(struct ata_port *ap)
-{
-        /* TODO */
-}
-
 static irqreturn_t ahci_interrupt(int irq, void *dev_instance)
 {
         struct ata_host *host = dev_instance;