Check timer protocol number for direct plugins

Check timer protocol number before enabling TREAD mode for direct plugins.

diff --git a/src/pcm/pcm_direct.c b/src/pcm/pcm_direct.c
index 6bded40fed613dee054e76e325cd3578eb3921c1..4991a83863b8fabba7020a5f83bd224299b4cc38 100644 (file)
--- a/src/pcm/pcm_direct.c
+++ b/src/pcm/pcm_direct.c
@@ -849,6 +849,7 @@ int snd_pcm_direct_initialize_poll_fd(snd_pcm_direct_t *dmix)
        snd_pcm_info_t *info;
        snd_timer_params_t *params;
        char name[128];
+       int tread = 0;
        struct pollfd fd;
        int capture = dmix->type == SND_PCM_TYPE_DSNOOP ? 1 : 0;
        
@@ -864,26 +865,45 @@ int snd_pcm_direct_initialize_poll_fd(snd_pcm_direct_t *dmix)
                                snd_pcm_info_get_card(info),
                                snd_pcm_info_get_device(info),
                                snd_pcm_info_get_subdevice(info) * 2 + capture);
-       ret = snd_timer_open(&dmix->timer, name, SND_TIMER_OPEN_NONBLOCK | SND_TIMER_OPEN_TREAD);
+       ret = snd_timer_open(&dmix->timer, name, SND_TIMER_OPEN_NONBLOCK
+                            /*| SND_TIMER_OPEN_TREAD*/);  /* XXX: TREAD is set later */
        if (ret < 0) {
                SNDERR("unable to open timer '%s'", name);
                return ret;
        }
+
+       if (snd_timer_poll_descriptors_count(dmix->timer) != 1) {
+               SNDERR("unable to use timer with fd more than one!!!", name);
+               return ret;
+       }
+       snd_timer_poll_descriptors(dmix->timer, &fd, 1);
+       dmix->poll_fd = fd.fd;
+
+       /*
+        * A hack to avoid Oops in the older kernel
+        *
+        * Enable TREAD mode only when protocl is newer than 2.0.2.
+        */
+       {
+               int ver = 0;
+               ioctl(dmix->poll_fd, SNDRV_TIMER_IOCTL_PVERSION, &ver);
+               if (ver >= SNDRV_PROTOCOL_VERSION(2, 0, 3)) {
+                       tread = 1;
+                       if (ioctl(dmix->poll_fd, SNDRV_TIMER_IOCTL_TREAD, &tread) < 0)
+                               tread = 0;
+               }
+       }
+
        snd_timer_params_set_auto_start(params, 1);
        snd_timer_params_set_early_event(params, 1);
        snd_timer_params_set_ticks(params, 1);
-       snd_timer_params_set_filter(params, (1<<SND_TIMER_EVENT_TICK)|(1<<SND_TIMER_EVENT_MPAUSE));
+       if (tread)
+               snd_timer_params_set_filter(params, (1<<SND_TIMER_EVENT_TICK)|(1<<SND_TIMER_EVENT_MPAUSE));
        ret = snd_timer_params(dmix->timer, params);
        if (ret < 0) {
                SNDERR("unable to set timer parameters", name);
                 return ret;
        }
-       if (snd_timer_poll_descriptors_count(dmix->timer) != 1) {
-               SNDERR("unable to use timer with fd more than one!!!", name);
-               return ret;
-       }
-       snd_timer_poll_descriptors(dmix->timer, &fd, 1);
-       dmix->poll_fd = fd.fd;
        return 0;
 }