ASoC: core: Allow topology to override machine driver FE DAI link config.

Machine drivers statically define a number of DAI links that currently
cannot be changed or removed by topology. This means PCMs and platform
components cannot be changed by topology at runtime AND machine drivers
are tightly coupled to topology.

This patch allows topology to override the machine driver DAI link config
in order to reuse machine drivers with different topologies and platform
components. The patch supports :-

1) create new FE PCMs with a topology defined PCM ID.
2) destroy existing static FE PCMs
3) change the platform component driver.
4) assign any new HW params fixups.
5) assign a new card name prefix to differentiate this topology to userspace.

The patch requires no changes to the machine drivers, but does add some
platform component flags that the platform component driver can assign
before loading topologies.

Signed-off-by: Liam Girdwood <liam.r.girdwood@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 12 insertions, 0 deletions

diff --git a/sound/soc/soc-pcm.c b/sound/soc/soc-pcm.c
index c2a31b51da4f..b7e67b871c0c 100644
--- a/sound/soc/soc-pcm.c
+++ b/sound/soc/soc-pcm.c
@@ -859,8 +859,20 @@ int soc_dai_hw_params(struct snd_pcm_substream *substream,
                       struct snd_pcm_hw_params *params,
                       struct snd_soc_dai *dai)
 {
+        struct snd_soc_pcm_runtime *rtd = substream->private_data;
         int ret;
 
+        /* perform any topology hw_params fixups before DAI  */
+        if (rtd->dai_link->be_hw_params_fixup) {
+                ret = rtd->dai_link->be_hw_params_fixup(rtd, params);
+                if (ret < 0) {
+                        dev_err(rtd->dev,
+                                "ASoC: hw_params topology fixup failed %d\n",
+                                ret);
+                        return ret;
+                }
+        }
+
         if (dai->driver->ops->hw_params) {
                 ret = dai->driver->ops->hw_params(substream, params, dai);
                 if (ret < 0) {