firewire: core: improve reread_config_rom() interface

The return value of reread_config_rom() was a mixture of two pieces of
information: whether the function succeeded, and whether the config rom
had changed.

To clarify the semantics, and to allow returning the actual error code,
split the second information into a new output parameter.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

1 files changed, 19 insertions, 21 deletions

diff --git a/drivers/firewire/core-device.c b/drivers/firewire/core-device.c
index 8038311e1737..f9f782afedf2 100644
--- a/drivers/firewire/core-device.c
+++ b/drivers/firewire/core-device.c
@@ -1069,31 +1069,30 @@ static void fw_device_init(struct work_struct *work)
         put_device(&device->device);    /* our reference */
 }
 
-enum {
-        REREAD_BIB_ERROR,
-        REREAD_BIB_UNCHANGED,
-        REREAD_BIB_CHANGED,
-};
-
 /* Reread and compare bus info block and header of root directory */
-static int reread_config_rom(struct fw_device *device, int generation)
+static int reread_config_rom(struct fw_device *device, int generation,
+                             bool *changed)
 {
         u32 q;
-        int i;
+        int i, rcode;
 
         for (i = 0; i < 6; i++) {
-                if (read_rom(device, generation, i, &q) != RCODE_COMPLETE)
-                        return REREAD_BIB_ERROR;
+                rcode = read_rom(device, generation, i, &q);
+                if (rcode != RCODE_COMPLETE)
+                        return rcode;
 
                 if (i == 0 && q == 0)
                         /* inaccessible (see read_config_rom); retry later */
-                        return REREAD_BIB_ERROR;
+                        return RCODE_BUSY;
 
-                if (q != device->config_rom[i])
-                        return REREAD_BIB_CHANGED;
+                if (q != device->config_rom[i]) {
+                        *changed = true;
+                        return RCODE_COMPLETE;
+                }
         }
 
-        return REREAD_BIB_UNCHANGED;
+        *changed = false;
+        return RCODE_COMPLETE;
 }
 
 static void fw_device_refresh(struct work_struct *work)
@@ -1101,10 +1100,11 @@ static void fw_device_refresh(struct work_struct *work)
         struct fw_device *device =
                 container_of(work, struct fw_device, work.work);
         struct fw_card *card = device->card;
-        int node_id = device->node_id;
+        int ret, node_id = device->node_id;
+        bool changed;
 
-        switch (reread_config_rom(device, device->generation)) {
-        case REREAD_BIB_ERROR:
+        ret = reread_config_rom(device, device->generation, &changed);
+        if (ret != RCODE_COMPLETE) {
                 if (device->config_rom_retries < MAX_RETRIES / 2 &&
                     atomic_read(&device->state) == FW_DEVICE_INITIALIZING) {
                         device->config_rom_retries++;
@@ -1113,8 +1113,9 @@ static void fw_device_refresh(struct work_struct *work)
                         return;
                 }
                 goto give_up;
+        }
 
-        case REREAD_BIB_UNCHANGED:
+        if (!changed) {
                 if (atomic_cmpxchg(&device->state,
                                    FW_DEVICE_INITIALIZING,
                                    FW_DEVICE_RUNNING) == FW_DEVICE_GONE)
@@ -1123,9 +1124,6 @@ static void fw_device_refresh(struct work_struct *work)
                 fw_device_update(work);
                 device->config_rom_retries = 0;
                 goto out;
-
-        case REREAD_BIB_CHANGED:
-                break;
         }
 
         /*