[ALSA] dynamic minors (6/6): increase maximum number of sound cards

Modules: ALSA Core,Memalloc module,ALSA sequencer

With dynamic minor numbers, we can increase the number of sound cards.

This requires that the sequencer client numbers of some kernel drivers
are allocated dynamically, too.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>

1 files changed, 25 insertions, 6 deletions

diff --git a/sound/core/seq/seq_clientmgr.c b/sound/core/seq/seq_clientmgr.c
index 95bd5ae92b9..2a9c6b316b1 100644
--- a/sound/core/seq/seq_clientmgr.c
+++ b/sound/core/seq/seq_clientmgr.c
@@ -47,6 +47,10 @@
  * 
  */
 
+/* range for dynamically allocated client numbers of kernel drivers */
+#define SNDRV_SEQ_DYNAMIC_CLIENT_BEGIN  16
+#define SNDRV_SEQ_DYNAMIC_CLIENT_END    48
+
 #define SNDRV_SEQ_LFLG_INPUT    0x0001
 #define SNDRV_SEQ_LFLG_OUTPUT   0x0002
 #define SNDRV_SEQ_LFLG_OPEN     (SNDRV_SEQ_LFLG_INPUT|SNDRV_SEQ_LFLG_OUTPUT)
@@ -203,7 +207,8 @@ int __init client_init_data(void)
 }
 
 
-static struct snd_seq_client *seq_create_client1(int client_index, int poolsize)
+static struct snd_seq_client *seq_create_client1(int client_index, int poolsize,
+                                                 int kernel_client)
 {
         unsigned long flags;
         int c;
@@ -227,7 +232,15 @@ static struct snd_seq_client *seq_create_client1(int client_index, int poolsize)
         /* find free slot in the client table */
         spin_lock_irqsave(&clients_lock, flags);
         if (client_index < 0) {
-                for (c = 128; c < SNDRV_SEQ_MAX_CLIENTS; c++) {
+                int cmin, cmax;
+                if (kernel_client) {
+                        cmin = SNDRV_SEQ_DYNAMIC_CLIENT_BEGIN;
+                        cmax = SNDRV_SEQ_DYNAMIC_CLIENT_END;
+                } else {
+                        cmin = 128;
+                        cmax = SNDRV_SEQ_MAX_CLIENTS;
+                }
+                for (c = cmin; c < cmax; c++) {
                         if (clienttab[c] || clienttablock[c])
                                 continue;
                         clienttab[client->number = c] = client;
@@ -306,7 +319,7 @@ static int snd_seq_open(struct inode *inode, struct file *file)
 
         if (down_interruptible(&register_mutex))
                 return -ERESTARTSYS;
-        client = seq_create_client1(-1, SNDRV_SEQ_DEFAULT_EVENTS);
+        client = seq_create_client1(-1, SNDRV_SEQ_DEFAULT_EVENTS, 0);
         if (client == NULL) {
                 up(&register_mutex);
                 return -ENOMEM; /* failure code */
@@ -2212,13 +2225,19 @@ int snd_seq_create_kernel_client(struct snd_card *card, int client_index,
                 return -EINVAL;
         if (card == NULL && client_index > 63)
                 return -EINVAL;
-        if (card)
-                client_index += 64 + (card->number << 2);
 
         if (down_interruptible(&register_mutex))
                 return -ERESTARTSYS;
+
+        if (card) {
+                if (card->number < 16)
+                        client_index += 64 + (card->number << 2);
+                else
+                        client_index = -1;
+        }
+
         /* empty write queue as default */
-        client = seq_create_client1(client_index, 0);
+        client = seq_create_client1(client_index, 0, 1);
         if (client == NULL) {
                 up(&register_mutex);
                 return -EBUSY;  /* failure code */