PCI: endpoint: Fix EPF device name to support multi-function devices

Fix the pci_epf_make() function so it can now bind many EPF devices to the
same EPF driver.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@free-electrons.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>

diff --git a/drivers/pci/endpoint/pci-ep-cfs.c b/drivers/pci/endpoint/pci-ep-cfs.c
index 4f74386c1ced797c8fa98e0faae671adacfa2680..48a89dff0e7fa0ff640285b8d833e2ca812c92ed 100644 (file)
--- a/drivers/pci/endpoint/pci-ep-cfs.c
+++ b/drivers/pci/endpoint/pci-ep-cfs.c
@@ -18,18 +18,22 @@
  */
 
 #include <linux/module.h>
+#include <linux/idr.h>
 #include <linux/slab.h>
 
 #include <linux/pci-epc.h>
 #include <linux/pci-epf.h>
 #include <linux/pci-ep-cfs.h>
 
+static DEFINE_IDR(functions_idr);
+static DEFINE_MUTEX(functions_mutex);
 static struct config_group *functions_group;
 static struct config_group *controllers_group;
 
 struct pci_epf_group {
        struct config_group group;
        struct pci_epf *epf;
+       int index;
 };
 
 struct pci_epc_group {
@@ -353,6 +357,9 @@ static void pci_epf_release(struct config_item *item)
 {
        struct pci_epf_group *epf_group = to_pci_epf_group(item);
 
+       mutex_lock(&functions_mutex);
+       idr_remove(&functions_idr, epf_group->index);
+       mutex_unlock(&functions_mutex);
        pci_epf_destroy(epf_group->epf);
        kfree(epf_group);
 }
@@ -372,22 +379,57 @@ static struct config_group *pci_epf_make(struct config_group *group,
 {
        struct pci_epf_group *epf_group;
        struct pci_epf *epf;
+       char *epf_name;
+       int index, err;
 
        epf_group = kzalloc(sizeof(*epf_group), GFP_KERNEL);
        if (!epf_group)
                return ERR_PTR(-ENOMEM);
 
+       mutex_lock(&functions_mutex);
+       index = idr_alloc(&functions_idr, epf_group, 0, 0, GFP_KERNEL);
+       mutex_unlock(&functions_mutex);
+       if (index < 0) {
+               err = index;
+               goto free_group;
+       }
+
+       epf_group->index = index;
+
        config_group_init_type_name(&epf_group->group, name, &pci_epf_type);
 
-       epf = pci_epf_create(group->cg_item.ci_name);
+       epf_name = kasprintf(GFP_KERNEL, "%s.%d",
+                            group->cg_item.ci_name, epf_group->index);
+       if (!epf_name) {
+               err = -ENOMEM;
+               goto remove_idr;
+       }
+
+       epf = pci_epf_create(epf_name);
        if (IS_ERR(epf)) {
                pr_err("failed to create endpoint function device\n");
-               return ERR_PTR(-EINVAL);
+               err = -EINVAL;
+               goto free_name;
        }
 
        epf_group->epf = epf;
 
+       kfree(epf_name);
+
        return &epf_group->group;
+
+free_name:
+       kfree(epf_name);
+
+remove_idr:
+       mutex_lock(&functions_mutex);
+       idr_remove(&functions_idr, epf_group->index);
+       mutex_unlock(&functions_mutex);
+
+free_group:
+       kfree(epf_group);
+
+       return ERR_PTR(err);
 }
 
 static void pci_epf_drop(struct config_group *group, struct config_item *item)