[PATCH 4/6] Factorize common MSI detection code from pci_enable_msi() and msix()

From: Brice Goglin
Date: Tue Jun 20 2006 - 22:31:28 EST


[PATCH 4/6] Factorize common MSI detection code from pci_enable_msi() and msix()

pci_enable_msi() and pci_enable_msix() have to check same things
before enabling MSI. Factorize this code in pci_msi_supported().

Signed-off-by: Brice Goglin <brice@xxxxxxxx>
---
drivers/pci/msi.c | 46 ++++++++++++++++++++++++++--------------------
1 file changed, 26 insertions(+), 20 deletions(-)

Index: linux-mm/drivers/pci/msi.c
===================================================================
--- linux-mm.orig/drivers/pci/msi.c 2006-06-20 22:02:03.000000000 -0400
+++ linux-mm/drivers/pci/msi.c 2006-06-20 22:03:47.000000000 -0400
@@ -902,6 +902,28 @@
}

/**
+ * pci_msi_supported - check whether MSI may be enabled on device
+ * @dev: pointer to the pci_dev data structure of MSI device function
+ *
+ * Check parent busses for MSI flags, or disable except
+ * if forced.
+ **/
+static
+int pci_msi_supported(struct pci_dev * dev)
+{
+ struct pci_bus *bus;
+
+ if (!pci_msi_enable || !dev || dev->no_msi)
+ return -1;
+
+ for (bus = dev->bus; bus; bus = bus->parent)
+ if (bus->bus_flags & PCI_BUS_FLAGS_NO_MSI)
+ return -1;
+
+ return 0;
+}
+
+/**
* pci_enable_msi - configure device's MSI capability structure
* @dev: pointer to the pci_dev data structure of MSI device function
*
@@ -913,19 +935,11 @@
**/
int pci_enable_msi(struct pci_dev* dev)
{
- struct pci_bus *bus;
- int pos, temp, status = -EINVAL;
+ int pos, temp, status;
u16 control;

- if (!pci_msi_enable || !dev)
- return status;
-
- if (dev->no_msi)
- return status;
-
- for (bus = dev->bus; bus; bus = bus->parent)
- if (bus->bus_flags & PCI_BUS_FLAGS_NO_MSI)
- return -EINVAL;
+ if (pci_msi_supported(dev) < 0)
+ return -EINVAL;

temp = dev->irq;

@@ -1135,22 +1149,14 @@
**/
int pci_enable_msix(struct pci_dev* dev, struct msix_entry *entries, int nvec)
{
- struct pci_bus *bus;
int status, pos, nr_entries, free_vectors;
int i, j, temp;
u16 control;
unsigned long flags;

- if (!pci_msi_enable || !dev || !entries)
+ if (!entries || pci_msi_supported(dev) < 0)
return -EINVAL;

- if (dev->no_msi)
- return -EINVAL;
-
- for (bus = dev->bus; bus; bus = bus->parent)
- if (bus->bus_flags & PCI_BUS_FLAGS_NO_MSI)
- return -EINVAL;
-
status = msi_init();
if (status < 0)
return status;
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/