diff options
Diffstat (limited to 'drivers/of')
| -rw-r--r-- | drivers/of/irq.c | 44 |
1 files changed, 40 insertions, 4 deletions
diff --git a/drivers/of/irq.c b/drivers/of/irq.c index 65c3c23255b7..1cd93549d093 100644 --- a/drivers/of/irq.c +++ b/drivers/of/irq.c @@ -671,6 +671,36 @@ err: } } +static int of_check_msi_parent(struct device_node *dev_node, struct device_node **msi_node) +{ + struct of_phandle_args msi_spec; + int ret; + + /* + * An msi-parent phandle with a missing or == 0 #msi-cells + * property identifies a 1:1 ID translation mapping. + * + * Set the msi controller node if the firmware matches this + * condition. + */ + ret = of_parse_phandle_with_optional_args(dev_node, "msi-parent", "#msi-cells", + 0, &msi_spec); + if (ret) + return ret; + + if ((*msi_node && *msi_node != msi_spec.np) || msi_spec.args_count != 0) + ret = -EINVAL; + + if (!ret) { + /* Return with a node reference held */ + *msi_node = msi_spec.np; + return 0; + } + of_node_put(msi_spec.np); + + return ret; +} + /** * of_msi_xlate - map a MSI ID and find relevant MSI controller node * @dev: device for which the mapping is to be done. @@ -678,7 +708,7 @@ err: * @id_in: Device ID. * * Walk up the device hierarchy looking for devices with a "msi-map" - * property. If found, apply the mapping to @id_in. + * or "msi-parent" property. If found, apply the mapping to @id_in. * If @msi_np points to a non-NULL device node pointer, only entries targeting * that node will be matched; if it points to a NULL value, it will receive the * device node of the first matching target phandle, with a reference held. @@ -692,14 +722,18 @@ u32 of_msi_xlate(struct device *dev, struct device_node **msi_np, u32 id_in) /* * Walk up the device parent links looking for one with a - * "msi-map" property. + * "msi-map" or an "msi-parent" property. */ - for (parent_dev = dev; parent_dev; parent_dev = parent_dev->parent) + for (parent_dev = dev; parent_dev; parent_dev = parent_dev->parent) { if (!of_map_id(parent_dev->of_node, id_in, "msi-map", "msi-map-mask", msi_np, &id_out)) break; + if (!of_check_msi_parent(parent_dev->of_node, msi_np)) + break; + } return id_out; } +EXPORT_SYMBOL_GPL(of_msi_xlate); /** * of_msi_map_get_device_domain - Use msi-map to find the relevant MSI domain @@ -741,8 +775,10 @@ struct irq_domain *of_msi_get_domain(struct device *dev, of_for_each_phandle(&it, err, np, "msi-parent", "#msi-cells", 0) { d = irq_find_matching_host(it.node, token); - if (d) + if (d) { + of_node_put(it.node); return d; + } } return NULL; |