From: Takashi Iwai <tiwai@suse.de>
Date: Tue, 27 Jan 2009 16:21:34 +0000 (+0100)
Subject: Fix plug conversion with mmap emulation
X-Git-Tag: v1.0.20~14
X-Git-Url: https://git.alsa-project.org/?a=commitdiff_plain;h=d3a8e853fb0780ecf85b54eba0926698970b3934;p=alsa-lib.git

Fix plug conversion with mmap emulation

If the slave PCM supports only another type of interleaved format,
plug did convert it wrongly and resulted in an unused access type
error.  For example, if a slave PCM supporst only RW_NONINTERLEAVE
access and you try to play an interleaved format file, it resulted
in an error.

This patch fixes the conversion rule.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
---

diff --git a/src/pcm/pcm_plug.c b/src/pcm/pcm_plug.c
index abd3d437..09028c98 100644
--- a/src/pcm/pcm_plug.c
+++ b/src/pcm/pcm_plug.c
@@ -605,7 +605,14 @@ static int snd_pcm_plug_change_mmap(snd_pcm_t *pcm, snd_pcm_t **new,
 				       plug->gen.slave != plug->req_slave);
 	if (err < 0)
 		return err;
-	slv->access = clt->access;
+	switch (slv->access) {
+	case SND_PCM_ACCESS_RW_INTERLEAVED:
+		slv->access = SND_PCM_ACCESS_MMAP_INTERLEAVED;
+		break;
+	case SND_PCM_ACCESS_RW_NONINTERLEAVED:
+		slv->access = SND_PCM_ACCESS_MMAP_NONINTERLEAVED;
+		break;
+	}
 	return 1;
 }
 #endif
@@ -743,19 +750,29 @@ static int check_access_change(snd_pcm_hw_params_t *cparams,
 		return 0; /* OK, we have mmap support */
 #ifdef BUILD_PCM_PLUGIN_MMAP_EMUL
 	/* no mmap support - we need mmap emulation */
+
+	if (!snd_pcm_access_mask_test(smask, SND_PCM_ACCESS_RW_INTERLEAVED) &&
+	    !snd_pcm_access_mask_test(smask, SND_PCM_ACCESS_RW_NONINTERLEAVED)) 
+		return -EINVAL; /* even no RW access?  no way! */
+
 	cmask = (const snd_pcm_access_mask_t *)
 		snd_pcm_hw_param_get_mask(cparams,
 					  SND_PCM_HW_PARAM_ACCESS);
 	snd_mask_none(&mask);
 	if (snd_pcm_access_mask_test(cmask, SND_PCM_ACCESS_RW_INTERLEAVED) ||
-	    snd_pcm_access_mask_test(cmask, SND_PCM_ACCESS_MMAP_INTERLEAVED))
-		snd_pcm_access_mask_set(&mask,
-					SND_PCM_ACCESS_RW_INTERLEAVED);
+	    snd_pcm_access_mask_test(cmask, SND_PCM_ACCESS_MMAP_INTERLEAVED)) {
+		if (snd_pcm_access_mask_test(smask, SND_PCM_ACCESS_RW_INTERLEAVED))
+			snd_pcm_access_mask_set(&mask,
+						SND_PCM_ACCESS_RW_INTERLEAVED);
+	}
 	if (snd_pcm_access_mask_test(cmask, SND_PCM_ACCESS_RW_NONINTERLEAVED) ||
-	    snd_pcm_access_mask_test(cmask, SND_PCM_ACCESS_MMAP_NONINTERLEAVED))
-		snd_pcm_access_mask_set(&mask,
-					SND_PCM_ACCESS_RW_NONINTERLEAVED);
-	*smask = mask;
+	    snd_pcm_access_mask_test(cmask, SND_PCM_ACCESS_MMAP_NONINTERLEAVED)) {
+		if (snd_pcm_access_mask_test(smask, SND_PCM_ACCESS_RW_NONINTERLEAVED))
+			snd_pcm_access_mask_set(&mask,
+						SND_PCM_ACCESS_RW_NONINTERLEAVED);
+	}
+	if (!snd_mask_empty(&mask))
+		*smask = mask; /* prefer the straight conversion */
 	return 0;
 #else
 	return -EINVAL;