ASoC: rsnd: don't fallback to PIO mode when -EPROBE_DEFER

Current rsnd driver will fallback to PIO mode if it can't get DMA
handler. But, DMA might return -EPROBE_DEFER when probe timing.
This driver always fallback to PIO mode especially from
commit ac6bbf0cdf4206c ("iommu: Remove IOMMU_OF_DECLARE") because
of this reason.

The DMA driver will be probed later, but sound driver might be
probed as PIO mode in such case. This patch fixup this issue.
Then, -EPROBE_DEFER is not error. Thus, let's don't indicate error
message in such case.
And it needs to call rsnd_adg_remove() individually if probe failed,
because it registers clk which should be unregister.

Maybe PIO fallback feature itself is not needed,
but let's keep it so far.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

2 files changed, 13 insertions, 1 deletions

diff --git a/sound/soc/sh/rcar/core.c b/sound/soc/sh/rcar/core.c
index b35f5509cfe2..d23c2bbff0cf 100644
--- a/sound/soc/sh/rcar/core.c
+++ b/sound/soc/sh/rcar/core.c
@@ -478,7 +478,7 @@ static int rsnd_status_update(u32 *status,
                         (func_call && (mod)->ops->fn) ? #fn : "");      \
                 if (func_call && (mod)->ops->fn)                        \
                         tmp = (mod)->ops->fn(mod, io, param);           \
-                if (tmp)                                                \
+                if (tmp && (tmp != -EPROBE_DEFER))                      \
                         dev_err(dev, "%s[%d] : %s error %d\n",          \
                                 rsnd_mod_name(mod), rsnd_mod_id(mod),   \
                                                      #fn, tmp);         \
@@ -1561,6 +1561,14 @@ exit_snd_probe:
                 rsnd_dai_call(remove, &rdai->capture, priv);
         }
 
+        /*
+         * adg is very special mod which can't use rsnd_dai_call(remove),
+         * and it registers ADG clock on probe.
+         * It should be unregister if probe failed.
+         * Mainly it is assuming -EPROBE_DEFER case
+         */
+        rsnd_adg_remove(priv);
+
         return ret;
 }
 
diff --git a/sound/soc/sh/rcar/dma.c b/sound/soc/sh/rcar/dma.c
index fe63ef8600d0..d65ea7bc4dac 100644
--- a/sound/soc/sh/rcar/dma.c
+++ b/sound/soc/sh/rcar/dma.c
@@ -241,6 +241,10 @@ static int rsnd_dmaen_attach(struct rsnd_dai_stream *io,
         /* try to get DMAEngine channel */
         chan = rsnd_dmaen_request_channel(io, mod_from, mod_to);
         if (IS_ERR_OR_NULL(chan)) {
+                /* Let's follow when -EPROBE_DEFER case */
+                if (PTR_ERR(chan) == -EPROBE_DEFER)
+                        return PTR_ERR(chan);
+
                 /*
                  * DMA failed. try to PIO mode
                  * see