At Thu, 13 May 2010 10:21:26 +0800, Wu Fengguang wrote:
On Wed, May 12, 2010 at 06:55:09PM +0800, Takashi Iwai wrote:
At Wed, 12 May 2010 12:20:33 +0200, Clemens Ladisch wrote:
Takashi Iwai wrote:
Wu Fengguang wrote:
Jaroslav Kysela wrote: > I don't agree to have only 4 slots for soundcards in the static minor > numbering. Maybe the driver should be converted to use subdevices or we > might drop the static minor number allocation at all (it might have only > impact for old distros).
Jaroslav, will there be so many sound cards in one system?
In the old time, yes. Now we have less and less PCI slots. In theory, we may have lots of USB audio devices, though :)
I implemented CONFIG_SND_DYNAMIC_MINORS because people had been asking for more than eight cards. (And by now I have lots of cards too, although my computer probably isn't very typical.)
Anyway, static numbering is needed only for systems without udev/devfs, and there we shouldn't change it for backwards compatibility. The HDA driver already requires kernels >= 2.6, so I don't see a problem with requiring CONFIG_SND_DYNAMIC_MINORS to get all HDMI outputs.
Right. We can make it dependent.
Like this?
config SND_HDA_CODEC_INTELHDMI bool "Build INTEL HDMI HD-audio codec support"
- select SND_DYNAMIC_MINORS default y
That will effectively turn on CONFIG_SND_DYNAMIC_MINORS by default (distribution kernels will have to enable it).
It's always a question whether we use "depends on" or "select". The former is safer while the latter is more intuitive.
In this particular case, I think "select" would be OK. If other guys have no objection, please repost the patch so that I can pick it up later.
Another backwards compatible solution is to fall back to the two reserved values. This makes me a bit more comfortable :)
As mentioned in another post, I don't see a big merit by it. In short: don't touch a working code :) The non-dynamic minors are only for old stuff, better to keep as is.
thanks,
Takashi
--- drm-intel.orig/include/sound/minors.h 2010-05-13 10:06:52.000000000 +0800 +++ drm-intel/include/sound/minors.h 2010-05-13 10:10:06.000000000 +0800 @@ -35,7 +35,9 @@ #define SNDRV_MINOR_TIMER (SNDRV_MINOR_GLOBAL + 1 * 32)
#ifndef CONFIG_SND_DYNAMIC_MINORS
/* 2 - 3 (reserved) */
+#define SNDRV_MINOR_BACKUP1 2 +#define SNDRV_MINOR_BACKUP2 3 #define SNDRV_MINOR_HWDEP 4 /* 4 - 7 */ #define SNDRV_MINOR_RAWMIDI 8 /* 8 - 15 */ #define SNDRV_MINOR_PCM_PLAYBACK 16 /* 16 - 23 */ --- drm-intel.orig/sound/core/sound.c 2010-05-13 10:06:04.000000000 +0800 +++ drm-intel/sound/core/sound.c 2010-05-13 10:11:19.000000000 +0800 @@ -269,8 +269,14 @@ int snd_register_device_for_dev(int type minor = snd_find_free_minor(); #else minor = snd_kernel_minor(type, card, dev);
- if (minor >= 0 && snd_minors[minor])
minor = -EBUSY;
- if (minor >= 0) {
if (snd_minors[minor])minor = SNDRV_MINOR_BACKUP1;if (snd_minors[minor])minor = SNDRV_MINOR_BACKUP2;if (snd_minors[minor])minor = -EBUSY;- }
#endif if (minor < 0) { mutex_unlock(&sound_mutex);
Thanks, Fengguang