| Message ID | 1418929903-8506-1-git-send-email-l.stach@pengutronix.de (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
On Thu, Dec 18, 2014 at 08:11:42PM +0100, Lucas Stach wrote: > This adds a simple way to get the root port a given device > is connected to. > > Signed-off-by: Lucas Stach <l.stach@pengutronix.de> > --- > v2: new patch in v2 > --- > drivers/pci/search.c | 20 ++++++++++++++++++++ > include/linux/pci.h | 1 + > 2 files changed, 21 insertions(+) > > diff --git a/drivers/pci/search.c b/drivers/pci/search.c > index a81f413083e4..c3ae1c52c7cf 100644 > --- a/drivers/pci/search.c > +++ b/drivers/pci/search.c > @@ -385,3 +385,23 @@ int pci_dev_present(const struct pci_device_id *ids) > return 0; > } > EXPORT_SYMBOL(pci_dev_present); > + > +/** > + * pci_get_rootport - Returns the root port the given device is connected to. > + * @dev: PCI device for which the root port should be found. > + */ > +struct pci_dev *pci_get_rootport(struct pci_dev *dev) I think pci_find_root_port() would be slightly more consistent with the existing API. Thierry
diff --git a/drivers/pci/search.c b/drivers/pci/search.c index a81f413083e4..c3ae1c52c7cf 100644 --- a/drivers/pci/search.c +++ b/drivers/pci/search.c @@ -385,3 +385,23 @@ int pci_dev_present(const struct pci_device_id *ids) return 0; } EXPORT_SYMBOL(pci_dev_present); + +/** + * pci_get_rootport - Returns the root port the given device is connected to. + * @dev: PCI device for which the root port should be found. + */ +struct pci_dev *pci_get_rootport(struct pci_dev *dev) +{ + struct pci_bus *bus = dev->bus; + + /* If there is no bridge on the bus the passed device is a root port. */ + if (!bus->self) + return dev; + + /* Walk up the PCI hierarchy to the first level below the root. */ + while (bus->parent && bus->parent->self) + bus = bus->parent; + + return bus->self; +} +EXPORT_SYMBOL(pci_get_rootport); diff --git a/include/linux/pci.h b/include/linux/pci.h index 4c8ac5fcc224..05442db50cad 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -843,6 +843,7 @@ static inline struct pci_dev *pci_get_bus_and_slot(unsigned int bus, } struct pci_dev *pci_get_class(unsigned int class, struct pci_dev *from); int pci_dev_present(const struct pci_device_id *ids); +struct pci_dev *pci_get_rootport(struct pci_dev *dev); int pci_bus_read_config_byte(struct pci_bus *bus, unsigned int devfn, int where, u8 *val);
This adds a simple way to get the root port a given device is connected to. Signed-off-by: Lucas Stach <l.stach@pengutronix.de> --- v2: new patch in v2 --- drivers/pci/search.c | 20 ++++++++++++++++++++ include/linux/pci.h | 1 + 2 files changed, 21 insertions(+)