ahci: Store irq number in struct ahci_host_priv

Currently, ahci supports only msi and intx. To also support msix the
handling of the irq number need to be changed. The irq number for msix
devices is taken from msi_list instead of pci_dev. Thus, the irq
number of a device needs to be stored in struct ahci_host_priv now.
This allows the host controller to be activated in a generic way.

This change is only intended for ahci drivers. For that reason the irq
number is stored in struct ahci_host_priv used only by ahci drivers.
Thus, the ABI changes only for ahci_host_activate(), but existing ata
drivers (about 50) are unaffected and keep unchanged. All users of
ahci_host_activate() have been updated.

While touching drivers/ata/libahci.c, doing a small code cleanup in
ahci_port_start().

Signed-off-by: Robert Richter <rrichter@cavium.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

1 files changed, 7 insertions, 9 deletions

diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c
index 1add5baec584..1c99402a1017 100644
--- a/drivers/ata/libahci.c
+++ b/drivers/ata/libahci.c
@@ -2344,7 +2344,7 @@ static int ahci_port_start(struct ata_port *ap)
         /*
          * Switch to per-port locking in case each port has its own MSI vector.
          */
-        if ((hpriv->flags & AHCI_HFLAG_MULTI_MSI)) {
+        if (hpriv->flags & AHCI_HFLAG_MULTI_MSI) {
                 spin_lock_init(&pp->lock);
                 ap->lock = &pp->lock;
         }
@@ -2472,7 +2472,10 @@ static int ahci_host_activate_multi_irqs(struct ata_host *host, int irq,
         rc = ata_host_start(host);
         if (rc)
                 return rc;
-
+        /*
+         * Requests IRQs according to AHCI-1.1 when multiple MSIs were
+         * allocated. That is one MSI per port, starting from @irq.
+         */
         for (i = 0; i < host->n_ports; i++) {
                 struct ahci_port_priv *pp = host->ports[i]->private_data;
 
@@ -2511,23 +2514,18 @@ out_free_irqs:
 /**
  *      ahci_host_activate - start AHCI host, request IRQs and register it
  *      @host: target ATA host
- *      @irq: base IRQ number to request
  *      @sht: scsi_host_template to use when registering the host
  *
- *      Similar to ata_host_activate, but requests IRQs according to AHCI-1.1
- *      when multiple MSIs were allocated. That is one MSI per port, starting
- *      from @irq.
- *
  *      LOCKING:
  *      Inherited from calling layer (may sleep).
  *
  *      RETURNS:
  *      0 on success, -errno otherwise.
  */
-int ahci_host_activate(struct ata_host *host, int irq,
-                       struct scsi_host_template *sht)
+int ahci_host_activate(struct ata_host *host, struct scsi_host_template *sht)
 {
         struct ahci_host_priv *hpriv = host->private_data;
+        int irq = hpriv->irq;
         int rc;
 
         if (hpriv->flags & AHCI_HFLAG_MULTI_MSI)