diff mbox

[RFC,1/4] PCI: Add hooks to allocate/free IRQ resources when binding/unbinding driver

Message ID 1430968374-29286-2-git-send-email-jiang.liu@linux.intel.com (mailing list archive)
State New, archived
Headers show

Commit Message

Jiang Liu May 7, 2015, 3:12 a.m. UTC
Add two hook points pcibios_{alloc|free}_irq() into PCI core, which will
be called when binding/unbinding PCI device drivers. Then PCI arch code
may hook into these two points to allocate IRQ resources on demand and
free them when not used anymore.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
---
 drivers/pci/pci-driver.c |   33 +++++++++++++++++++++++----------
 include/linux/pci.h      |    2 ++
 2 files changed, 25 insertions(+), 10 deletions(-)

Comments

Bjorn Helgaas May 19, 2015, 2:45 p.m. UTC | #1
On Thu, May 07, 2015 at 11:12:51AM +0800, Jiang Liu wrote:
> Add two hook points pcibios_{alloc|free}_irq() into PCI core, which will
> be called when binding/unbinding PCI device drivers. Then PCI arch code
> may hook into these two points to allocate IRQ resources on demand and
> free them when not used anymore.
> 
> Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
> ---
>  drivers/pci/pci-driver.c |   33 +++++++++++++++++++++++----------
>  include/linux/pci.h      |    2 ++
>  2 files changed, 25 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
> index 3cb2210de553..8af4a671686f 100644
> --- a/drivers/pci/pci-driver.c
> +++ b/drivers/pci/pci-driver.c
> ...
> +static int pci_device_probe(struct device *dev)
> +{
> +	int error;
> +	struct pci_dev *pci_dev = to_pci_dev(dev);
> +	struct pci_driver *drv = to_pci_driver(dev->driver);
> +
> +	error = pcibios_alloc_irq(pci_dev);
> +	if (error >= 0) {
> +		pci_dev_get(pci_dev);
> +		error = __pci_device_probe(drv, pci_dev);
> +		if (error) {
> +			pcibios_free_irq(pci_dev);
> +			pci_dev_put(pci_dev);
> +		}
> +	}

Please structure it like this so the mainline code doesn't get buried in
the body of the "if":

    irq = pcibios_alloc_irq(pci_dev);
    if (irq < 0)
	return irq;

    pci_dev_get(pci_dev);
    ...

>  
>  	return error;
>  }
--
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diff mbox

Patch

diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index 3cb2210de553..8af4a671686f 100644
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -388,18 +388,30 @@  static int __pci_device_probe(struct pci_driver *drv, struct pci_dev *pci_dev)
 	return error;
 }
 
-static int pci_device_probe(struct device *dev)
+int __weak pcibios_alloc_irq(struct pci_dev *dev)
 {
-	int error = 0;
-	struct pci_driver *drv;
-	struct pci_dev *pci_dev;
+	return dev->irq;
+}
 
-	drv = to_pci_driver(dev->driver);
-	pci_dev = to_pci_dev(dev);
-	pci_dev_get(pci_dev);
-	error = __pci_device_probe(drv, pci_dev);
-	if (error)
-		pci_dev_put(pci_dev);
+void __weak pcibios_free_irq(struct pci_dev *dev)
+{
+}
+
+static int pci_device_probe(struct device *dev)
+{
+	int error;
+	struct pci_dev *pci_dev = to_pci_dev(dev);
+	struct pci_driver *drv = to_pci_driver(dev->driver);
+
+	error = pcibios_alloc_irq(pci_dev);
+	if (error >= 0) {
+		pci_dev_get(pci_dev);
+		error = __pci_device_probe(drv, pci_dev);
+		if (error) {
+			pcibios_free_irq(pci_dev);
+			pci_dev_put(pci_dev);
+		}
+	}
 
 	return error;
 }
@@ -415,6 +427,7 @@  static int pci_device_remove(struct device *dev)
 			drv->remove(pci_dev);
 			pm_runtime_put_noidle(dev);
 		}
+		pcibios_free_irq(pci_dev);
 		pci_dev->driver = NULL;
 	}
 
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 353db8dc4c6e..f50d16a04abc 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1656,6 +1656,8 @@  int pcibios_set_pcie_reset_state(struct pci_dev *dev,
 int pcibios_add_device(struct pci_dev *dev);
 void pcibios_release_device(struct pci_dev *dev);
 void pcibios_penalize_isa_irq(int irq, int active);
+int pcibios_alloc_irq(struct pci_dev *dev);
+void pcibios_free_irq(struct pci_dev *dev);
 
 #ifdef CONFIG_HIBERNATE_CALLBACKS
 extern struct dev_pm_ops pcibios_pm_ops;