greybus: es2: clean up CDSI CPort reservation

[cascardo/linux.git] / drivers / staging / greybus / hd.c

diff --git a/drivers/staging/greybus/hd.c b/drivers/staging/greybus/hd.c
index 2863472..b87e086 100644 (file)
--- a/drivers/staging/greybus/hd.c
+++ b/drivers/staging/greybus/hd.c
@@ -39,6 +39,47 @@ static struct attribute *bus_attrs[] = {
 };
 ATTRIBUTE_GROUPS(bus);
 
+int gb_hd_cport_reserve(struct gb_host_device *hd, u16 cport_id)
+{
+       struct ida *id_map = &hd->cport_id_map;
+       int ret;
+
+       ret = ida_simple_get(id_map, cport_id, cport_id + 1, GFP_KERNEL);
+       if (ret < 0) {
+               dev_err(&hd->dev, "failed to reserve cport %u\n", cport_id);
+               return ret;
+       }
+
+       return 0;
+}
+EXPORT_SYMBOL_GPL(gb_hd_cport_reserve);
+
+/* Locking: Caller guarantees serialisation */
+int gb_hd_cport_allocate(struct gb_host_device *hd, int cport_id)
+{
+       struct ida *id_map = &hd->cport_id_map;
+       int ida_start, ida_end;
+
+       if (cport_id < 0) {
+               ida_start = 0;
+               ida_end = hd->num_cports;
+       } else if (cport_id < hd->num_cports) {
+               ida_start = cport_id;
+               ida_end = cport_id + 1;
+       } else {
+               dev_err(&hd->dev, "cport %d not available\n", cport_id);
+               return -EINVAL;
+       }
+
+       return ida_simple_get(id_map, ida_start, ida_end, GFP_KERNEL);
+}
+
+/* Locking: Caller guarantees serialisation */
+void gb_hd_cport_release(struct gb_host_device *hd, u16 cport_id)
+{
+       ida_simple_remove(&hd->cport_id_map, cport_id);
+}
+
 static void gb_hd_release(struct device *dev)
 {
        struct gb_host_device *hd = to_gb_host_device(dev);