kernel-fxtec-pro1x/drivers/of/of_pci.c
Thomas Petazzoni 0d5a6db3aa of: pci: add registry of MSI chips
This commit adds a very basic registry of msi_chip structures, so that
an IRQ controller driver can register an msi_chip, and a PCIe host
controller can find it, based on a 'struct device_node'.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
2013-08-12 15:27:01 +00:00

136 lines
3.2 KiB
C

#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/of.h>
#include <linux/of_pci.h>
#include <asm/prom.h>
static inline int __of_pci_pci_compare(struct device_node *node,
unsigned int data)
{
int devfn;
devfn = of_pci_get_devfn(node);
if (devfn < 0)
return 0;
return devfn == data;
}
struct device_node *of_pci_find_child_device(struct device_node *parent,
unsigned int devfn)
{
struct device_node *node, *node2;
for_each_child_of_node(parent, node) {
if (__of_pci_pci_compare(node, devfn))
return node;
/*
* Some OFs create a parent node "multifunc-device" as
* a fake root for all functions of a multi-function
* device we go down them as well.
*/
if (!strcmp(node->name, "multifunc-device")) {
for_each_child_of_node(node, node2) {
if (__of_pci_pci_compare(node2, devfn)) {
of_node_put(node);
return node2;
}
}
}
}
return NULL;
}
EXPORT_SYMBOL_GPL(of_pci_find_child_device);
/**
* of_pci_get_devfn() - Get device and function numbers for a device node
* @np: device node
*
* Parses a standard 5-cell PCI resource and returns an 8-bit value that can
* be passed to the PCI_SLOT() and PCI_FUNC() macros to extract the device
* and function numbers respectively. On error a negative error code is
* returned.
*/
int of_pci_get_devfn(struct device_node *np)
{
unsigned int size;
const __be32 *reg;
reg = of_get_property(np, "reg", &size);
if (!reg || size < 5 * sizeof(__be32))
return -EINVAL;
return (be32_to_cpup(reg) >> 8) & 0xff;
}
EXPORT_SYMBOL_GPL(of_pci_get_devfn);
/**
* of_pci_parse_bus_range() - parse the bus-range property of a PCI device
* @node: device node
* @res: address to a struct resource to return the bus-range
*
* Returns 0 on success or a negative error-code on failure.
*/
int of_pci_parse_bus_range(struct device_node *node, struct resource *res)
{
const __be32 *values;
int len;
values = of_get_property(node, "bus-range", &len);
if (!values || len < sizeof(*values) * 2)
return -EINVAL;
res->name = node->name;
res->start = be32_to_cpup(values++);
res->end = be32_to_cpup(values);
res->flags = IORESOURCE_BUS;
return 0;
}
EXPORT_SYMBOL_GPL(of_pci_parse_bus_range);
#ifdef CONFIG_PCI_MSI
static LIST_HEAD(of_pci_msi_chip_list);
static DEFINE_MUTEX(of_pci_msi_chip_mutex);
int of_pci_msi_chip_add(struct msi_chip *chip)
{
if (!of_property_read_bool(chip->of_node, "msi-controller"))
return -EINVAL;
mutex_lock(&of_pci_msi_chip_mutex);
list_add(&chip->list, &of_pci_msi_chip_list);
mutex_unlock(&of_pci_msi_chip_mutex);
return 0;
}
EXPORT_SYMBOL_GPL(of_pci_msi_chip_add);
void of_pci_msi_chip_remove(struct msi_chip *chip)
{
mutex_lock(&of_pci_msi_chip_mutex);
list_del(&chip->list);
mutex_unlock(&of_pci_msi_chip_mutex);
}
EXPORT_SYMBOL_GPL(of_pci_msi_chip_remove);
struct msi_chip *of_pci_find_msi_chip_by_node(struct device_node *of_node)
{
struct msi_chip *c;
mutex_lock(&of_pci_msi_chip_mutex);
list_for_each_entry(c, &of_pci_msi_chip_list, list) {
if (c->of_node == of_node) {
mutex_unlock(&of_pci_msi_chip_mutex);
return c;
}
}
mutex_unlock(&of_pci_msi_chip_mutex);
return NULL;
}
EXPORT_SYMBOL_GPL(of_pci_find_msi_chip_by_node);
#endif /* CONFIG_PCI_MSI */