firewire: optimize gap count with 1394b leaf nodes

Table-based gap count optimization cannot be used if 1394b repeater PHYs
are present.  But it does work with 1394b leaf nodes.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Kristian Høgsberg <krh@redhat.com>

4 files changed, 14 insertions, 17 deletions

diff --git a/drivers/firewire/fw-card.c b/drivers/firewire/fw-card.c
index 9eb1edacd825..0aeab3218bb6 100644
--- a/drivers/firewire/fw-card.c
+++ b/drivers/firewire/fw-card.c
@@ -336,8 +336,11 @@ fw_card_bm_work(struct work_struct *work)
         }
 
  pick_me:
-        /* Now figure out what gap count to set. */
-        if (card->topology_type == FW_TOPOLOGY_A &&
+        /*
+         * Pick a gap count from 1394a table E-1.  The table doesn't cover
+         * the typically much larger 1394b beta repeater delays though.
+         */
+        if (!card->beta_repeaters_present &&
             card->root_node->max_hops < ARRAY_SIZE(gap_count_table))
                 gap_count = gap_count_table[card->root_node->max_hops];
         else
diff --git a/drivers/firewire/fw-topology.c b/drivers/firewire/fw-topology.c
index 4e358506d913..77e3f8276007 100644
--- a/drivers/firewire/fw-topology.c
+++ b/drivers/firewire/fw-topology.c
@@ -172,7 +172,8 @@ static struct fw_node *build_tree(struct fw_card *card,
         struct list_head stack, *h;
         u32 *next_sid, *end, q;
         int i, port_count, child_port_count, phy_id, parent_count, stack_depth;
-        int gap_count, topology_type;
+        int gap_count;
+        bool beta_repeaters_present;
 
         local_node = NULL;
         node = NULL;
@@ -182,7 +183,7 @@ static struct fw_node *build_tree(struct fw_card *card,
         phy_id = 0;
         irm_node = NULL;
         gap_count = SELF_ID_GAP_COUNT(*sid);
-        topology_type = 0;
+        beta_repeaters_present = false;
 
         while (sid < end) {
                 next_sid = count_ports(sid, &port_count, &child_port_count);
@@ -224,11 +225,6 @@ static struct fw_node *build_tree(struct fw_card *card,
                 if (SELF_ID_CONTENDER(q))
                         irm_node = node;
 
-                if (node->phy_speed == SCODE_BETA)
-                        topology_type |= FW_TOPOLOGY_B;
-                else
-                        topology_type |= FW_TOPOLOGY_A;
-
                 parent_count = 0;
 
                 for (i = 0; i < port_count; i++) {
@@ -278,6 +274,10 @@ static struct fw_node *build_tree(struct fw_card *card,
                 list_add_tail(&node->link, &stack);
                 stack_depth += 1 - child_port_count;
 
+                if (node->phy_speed == SCODE_BETA &&
+                    parent_count + child_port_count > 1)
+                        beta_repeaters_present = true;
+
                 /*
                  * If all PHYs does not report the same gap count
                  * setting, we fall back to 63 which will force a gap
@@ -295,7 +295,7 @@ static struct fw_node *build_tree(struct fw_card *card,
         card->root_node = node;
         card->irm_node = irm_node;
         card->gap_count = gap_count;
-        card->topology_type = topology_type;
+        card->beta_repeaters_present = beta_repeaters_present;
 
         return local_node;
 }
diff --git a/drivers/firewire/fw-topology.h b/drivers/firewire/fw-topology.h
index 363b6cbcd0b3..aced9f7db358 100644
--- a/drivers/firewire/fw-topology.h
+++ b/drivers/firewire/fw-topology.h
@@ -20,12 +20,6 @@
 #define __fw_topology_h
 
 enum {
-        FW_TOPOLOGY_A =         0x01,
-        FW_TOPOLOGY_B =         0x02,
-        FW_TOPOLOGY_MIXED =     0x03,
-};
-
-enum {
         FW_NODE_CREATED =   0x00,
         FW_NODE_UPDATED =   0x01,
         FW_NODE_DESTROYED = 0x02,
diff --git a/drivers/firewire/fw-transaction.h b/drivers/firewire/fw-transaction.h
index f54eee4e3803..5abed193f4a6 100644
--- a/drivers/firewire/fw-transaction.h
+++ b/drivers/firewire/fw-transaction.h
@@ -245,7 +245,7 @@ struct fw_card {
         struct fw_node *irm_node;
         int color;
         int gap_count;
-        int topology_type;
+        bool beta_repeaters_present;
 
         int index;