libata: make sff_irq_on() method optional

Now, with the introduction of the sff_set_devctl() method, we can
use it in sff_irq_on() method too -- that way its implementations
in 'pata_bf54x' and 'pata_scc' become virtually identical to
ata_sff_irq_on().  The sff_irq_on() method now becomes quite
superfluous, and the only reason not to remove it completely is
the existence of the 'pata_octeon_cf' driver which implements it
as an empty function. Just make the method optional then, with
ata_sff_irq_on() becoming generic taskfile-bound function, still
global for the 'pata_bf54x' driver to be able to call it from its
thaw() and postreset() methods.

While at it, make the sff_irq_on() method and ata_sff_irq_on() return
'void' as the result is always ignored anyway.

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

5 files changed, 20 insertions, 66 deletions

diff --git a/drivers/ata/libata-sff.c b/drivers/ata/libata-sff.c
index 31b495fcd969..b7f7f8557fee 100644
--- a/drivers/ata/libata-sff.c
+++ b/drivers/ata/libata-sff.c
@@ -63,7 +63,6 @@ const struct ata_port_operations ata_sff_port_ops = {
         .sff_tf_read            = ata_sff_tf_read,
         .sff_exec_command       = ata_sff_exec_command,
         .sff_data_xfer          = ata_sff_data_xfer,
-        .sff_irq_on             = ata_sff_irq_on,
         .sff_irq_clear          = ata_sff_irq_clear,
 
         .lost_interrupt         = ata_sff_lost_interrupt,
@@ -538,24 +537,29 @@ void ata_dev_select(struct ata_port *ap, unsigned int device,
  *      Enable interrupts on a legacy IDE device using MMIO or PIO,
  *      wait for idle, clear any pending interrupts.
  *
+ *      Note: may NOT be used as the sff_irq_on() entry in
+ *      ata_port_operations.
+ *
  *      LOCKING:
  *      Inherited from caller.
  */
-u8 ata_sff_irq_on(struct ata_port *ap)
+void ata_sff_irq_on(struct ata_port *ap)
 {
         struct ata_ioports *ioaddr = &ap->ioaddr;
-        u8 tmp;
+
+        if (ap->ops->sff_irq_on) {
+                ap->ops->sff_irq_on(ap);
+                return;
+        }
 
         ap->ctl &= ~ATA_NIEN;
         ap->last_ctl = ap->ctl;
 
-        if (ioaddr->ctl_addr)
-                iowrite8(ap->ctl, ioaddr->ctl_addr);
-        tmp = ata_wait_idle(ap);
+        if (ap->ops->sff_set_devctl || ioaddr->ctl_addr)
+                ata_sff_set_devctl(ap, ap->ctl);
+        ata_wait_idle(ap);
 
         ap->ops->sff_irq_clear(ap);
-
-        return tmp;
 }
 EXPORT_SYMBOL_GPL(ata_sff_irq_on);
 
@@ -1186,7 +1190,7 @@ static void ata_hsm_qc_complete(struct ata_queued_cmd *qc, int in_wq)
                         qc = ata_qc_from_tag(ap, qc->tag);
                         if (qc) {
                                 if (likely(!(qc->err_mask & AC_ERR_HSM))) {
-                                        ap->ops->sff_irq_on(ap);
+                                        ata_sff_irq_on(ap);
                                         ata_qc_complete(qc);
                                 } else
                                         ata_port_freeze(ap);
@@ -1202,7 +1206,7 @@ static void ata_hsm_qc_complete(struct ata_queued_cmd *qc, int in_wq)
         } else {
                 if (in_wq) {
                         spin_lock_irqsave(ap->lock, flags);
-                        ap->ops->sff_irq_on(ap);
+                        ata_sff_irq_on(ap);
                         ata_qc_complete(qc);
                         spin_unlock_irqrestore(ap->lock, flags);
                 } else
@@ -1946,7 +1950,7 @@ void ata_sff_thaw(struct ata_port *ap)
         /* clear & re-enable interrupts */
         ap->ops->sff_check_status(ap);
         ap->ops->sff_irq_clear(ap);
-        ap->ops->sff_irq_on(ap);
+        ata_sff_irq_on(ap);
 }
 EXPORT_SYMBOL_GPL(ata_sff_thaw);
 
diff --git a/drivers/ata/pata_bf54x.c b/drivers/ata/pata_bf54x.c
index 198307534d90..07c110470e25 100644
--- a/drivers/ata/pata_bf54x.c
+++ b/drivers/ata/pata_bf54x.c
@@ -1228,30 +1228,6 @@ static void bfin_irq_clear(struct ata_port *ap)
 }
 
 /**
- *      bfin_irq_on - Enable interrupts on a port.
- *      @ap: Port on which interrupts are enabled.
- *
- *      Note: Original code is ata_sff_irq_on().
- */
-
-static unsigned char bfin_irq_on(struct ata_port *ap)
-{
-        void __iomem *base = (void __iomem *)ap->ioaddr.ctl_addr;
-        u8 tmp;
-
-        dev_dbg(ap->dev, "in atapi irq on\n");
-        ap->ctl &= ~ATA_NIEN;
-        ap->last_ctl = ap->ctl;
-
-        write_atapi_register(base, ATA_REG_CTRL, ap->ctl);
-        tmp = ata_wait_idle(ap);
-
-        bfin_irq_clear(ap);
-
-        return tmp;
-}
-
-/**
  *      bfin_thaw - Thaw DMA controller port
  *      @ap: port to thaw
  *
@@ -1262,7 +1238,7 @@ void bfin_thaw(struct ata_port *ap)
 {
         dev_dbg(ap->dev, "in atapi dma thaw\n");
         bfin_check_status(ap);
-        bfin_irq_on(ap);
+        ata_sff_irq_on(ap);
 }
 
 /**
@@ -1279,7 +1255,7 @@ static void bfin_postreset(struct ata_link *link, unsigned int *classes)
         void __iomem *base = (void __iomem *)ap->ioaddr.ctl_addr;
 
         /* re-enable interrupts */
-        bfin_irq_on(ap);
+        ata_sff_irq_on(ap);
 
         /* is double-select really necessary? */
         if (classes[0] != ATA_DEV_NONE)
@@ -1477,7 +1453,6 @@ static struct ata_port_operations bfin_pata_ops = {
         .postreset              = bfin_postreset,
 
         .sff_irq_clear          = bfin_irq_clear,
-        .sff_irq_on             = bfin_irq_on,
 
         .port_start             = bfin_port_start,
         .port_stop              = bfin_port_stop,
diff --git a/drivers/ata/pata_octeon_cf.c b/drivers/ata/pata_octeon_cf.c
index 005a44483a7b..303ca7e82408 100644
--- a/drivers/ata/pata_octeon_cf.c
+++ b/drivers/ata/pata_octeon_cf.c
@@ -489,9 +489,8 @@ static void octeon_cf_exec_command16(struct ata_port *ap,
         ata_wait_idle(ap);
 }
 
-static u8 octeon_cf_irq_on(struct ata_port *ap)
+static void octeon_cf_irq_on(struct ata_port *ap)
 {
-        return 0;
 }
 
 static void octeon_cf_irq_clear(struct ata_port *ap)
diff --git a/drivers/ata/pata_scc.c b/drivers/ata/pata_scc.c
index 86b25fef34a9..d3988991ca68 100644
--- a/drivers/ata/pata_scc.c
+++ b/drivers/ata/pata_scc.c
@@ -828,29 +828,6 @@ static unsigned int scc_data_xfer (struct ata_device *dev, unsigned char *buf,
 }
 
 /**
- *      scc_irq_on - Enable interrupts on a port.
- *      @ap: Port on which interrupts are enabled.
- *
- *      Note: Original code is ata_sff_irq_on().
- */
-
-static u8 scc_irq_on (struct ata_port *ap)
-{
-        struct ata_ioports *ioaddr = &ap->ioaddr;
-        u8 tmp;
-
-        ap->ctl &= ~ATA_NIEN;
-        ap->last_ctl = ap->ctl;
-
-        out_be32(ioaddr->ctl_addr, ap->ctl);
-        tmp = ata_wait_idle(ap);
-
-        ap->ops->sff_irq_clear(ap);
-
-        return tmp;
-}
-
-/**
  *      scc_pata_prereset - prepare for reset
  *      @ap: ATA port to be reset
  *      @deadline: deadline jiffies for the operation
@@ -977,7 +954,6 @@ static struct ata_port_operations scc_pata_ops = {
         .post_internal_cmd      = scc_bmdma_stop,
 
         .sff_irq_clear          = scc_irq_clear,
-        .sff_irq_on             = scc_irq_on,
 
         .port_start             = scc_port_start,
         .port_stop              = scc_port_stop,
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 6207ec600722..af700923a393 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -859,7 +859,7 @@ struct ata_port_operations {
                                  const struct ata_taskfile *tf);
         unsigned int (*sff_data_xfer)(struct ata_device *dev,
                         unsigned char *buf, unsigned int buflen, int rw);
-        u8   (*sff_irq_on)(struct ata_port *);
+        void (*sff_irq_on)(struct ata_port *);
         bool (*sff_irq_check)(struct ata_port *);
         void (*sff_irq_clear)(struct ata_port *);
 
@@ -1599,7 +1599,7 @@ extern unsigned int ata_sff_data_xfer32(struct ata_device *dev,
                         unsigned char *buf, unsigned int buflen, int rw);
 extern unsigned int ata_sff_data_xfer_noirq(struct ata_device *dev,
                         unsigned char *buf, unsigned int buflen, int rw);
-extern u8 ata_sff_irq_on(struct ata_port *ap);
+extern void ata_sff_irq_on(struct ata_port *ap);
 extern void ata_sff_irq_clear(struct ata_port *ap);
 extern int ata_sff_hsm_move(struct ata_port *ap, struct ata_queued_cmd *qc,
                             u8 status, int in_wq);