firewire: core: code refactoring for helper function to fill iso_resource parameters

This change is a preparation for future changes. The added helper function
will be reused in the changes to fill iso_resource parameters according to
the users' request.

Link: https://lore.kernel.org/r/20260429093449.160545-4-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>

diff --git a/drivers/firewire/core-cdev.c b/drivers/firewire/core-cdev.c
index 8391c7efab2ce65c8a41825ffe5f778381a5aad4..effa037396798df56656182c86e863ebca00f4cb 100644 (file)
--- a/drivers/firewire/core-cdev.c
+++ b/drivers/firewire/core-cdev.c
@@ -128,6 +128,12 @@ struct descriptor_resource {
        u32 data[];
 };
 
+struct iso_resource_params {
+       int generation;
+       u64 channels;
+       s32 bandwidth;
+};
+
 struct iso_resource {
        struct client_resource resource;
        struct client *client;
@@ -135,9 +141,7 @@ struct iso_resource {
        struct delayed_work work;
        enum {ISO_RES_ALLOC, ISO_RES_REALLOC, ISO_RES_DEALLOC,
              ISO_RES_ALLOC_ONCE, ISO_RES_DEALLOC_ONCE,} todo;
-       int generation;
-       u64 channels;
-       s32 bandwidth;
+       struct iso_resource_params params;
        struct iso_resource_event *e_alloc, *e_dealloc;
 };
 
@@ -1290,6 +1294,20 @@ static int ioctl_get_cycle_timer(struct client *client, union ioctl_arg *arg)
        return 0;
 }
 
+static int fill_iso_resource_params(struct iso_resource_params *params,
+                                   struct fw_cdev_allocate_iso_resource *request)
+{
+       if ((request->channels == 0 && request->bandwidth == 0) ||
+           request->bandwidth > BANDWIDTH_AVAILABLE_INITIAL)
+               return -EINVAL;
+
+       params->generation = -1;
+       params->channels = request->channels;
+       params->bandwidth = request->bandwidth;
+
+       return 0;
+}
+
 static void iso_resource_work(struct work_struct *work)
 {
        struct iso_resource_event *e;
@@ -1310,21 +1328,21 @@ static void iso_resource_work(struct work_struct *work)
                } else {
                        // We could be called twice within the same generation.
                        skip = todo == ISO_RES_REALLOC &&
-                              r->generation == generation;
+                              r->params.generation == generation;
                }
                free = todo == ISO_RES_DEALLOC ||
                       todo == ISO_RES_ALLOC_ONCE ||
                       todo == ISO_RES_DEALLOC_ONCE;
-               r->generation = generation;
+               r->params.generation = generation;
        }
 
        if (skip)
                goto out;
 
-       bandwidth = r->bandwidth;
+       bandwidth = r->params.bandwidth;
 
        fw_iso_resource_manage(client->device->card, generation,
-                       r->channels, &channel, &bandwidth,
+                       r->params.channels, &channel, &bandwidth,
                        todo == ISO_RES_ALLOC ||
                        todo == ISO_RES_REALLOC ||
                        todo == ISO_RES_ALLOC_ONCE);
@@ -1355,7 +1373,7 @@ static void iso_resource_work(struct work_struct *work)
        }
 
        if (todo == ISO_RES_ALLOC && channel >= 0)
-               r->channels = 1ULL << channel;
+               r->params.channels = 1ULL << channel;
 
        if (todo == ISO_RES_REALLOC && success)
                goto out;
@@ -1402,10 +1420,6 @@ static int init_iso_resource(struct client *client,
        struct iso_resource *r;
        int ret;
 
-       if ((request->channels == 0 && request->bandwidth == 0) ||
-           request->bandwidth > BANDWIDTH_AVAILABLE_INITIAL)
-               return -EINVAL;
-
        r = kmalloc_obj(*r);
        e1 = kmalloc_obj(*e1);
        e2 = kmalloc_obj(*e2);
@@ -1414,12 +1428,13 @@ static int init_iso_resource(struct client *client,
                goto fail;
        }
 
+       ret = fill_iso_resource_params(&r->params, request);
+       if (ret < 0)
+               goto fail;
+
        INIT_DELAYED_WORK(&r->work, iso_resource_work);
        r->client       = client;
        r->todo         = todo;
-       r->generation   = -1;
-       r->channels     = request->channels;
-       r->bandwidth    = request->bandwidth;
        r->e_alloc      = e1;
        r->e_dealloc    = e2;