ASoC: topology: Support topology file of ABI v4

Users start to use topology ABI from v4. ABI v5 updated existing manifest
and PCM elements. Two previous patches can support these ABI updates in a
backward compatible way. So if the topology file from user space is
generated by ABI v4, kernel will no longer quit but continue parsing.
Signed-off-by: Mengdong Lin <mengdong.lin@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

include/uapi/sound/asoc.h

@@ -83,7 +83,8 @@
 #define SND_SOC_TPLG_NUM_TEXTS		16
 
 /* ABI version */
-#define SND_SOC_TPLG_ABI_VERSION	0x5
+#define SND_SOC_TPLG_ABI_VERSION	0x5	/* current version */
+#define SND_SOC_TPLG_ABI_VERSION_MIN	0x4	/* oldest version supported */
 
 /* Max size of TLV data */
 #define SND_SOC_TPLG_TLV_SIZE		32

sound/soc/soc-topology.c

@@ -2056,7 +2056,9 @@ static int soc_valid_header(struct soc_tplg *tplg,
 		return -EINVAL;
 	}
 
-	if (hdr->abi != SND_SOC_TPLG_ABI_VERSION) {
+	/* Support ABI from version 4 */
+	if (hdr->abi > SND_SOC_TPLG_ABI_VERSION
+		|| hdr->abi < SND_SOC_TPLG_ABI_VERSION_MIN) {
 		dev_err(tplg->dev,
 			"ASoC: pass %d invalid ABI version got 0x%x need 0x%x at offset 0x%lx size 0x%zx.\n",
 			tplg->pass, hdr->abi,