[PATCH 4.18 076/135] ASoC: rsnd: dont fallback to PIO mode when -EPROBE_DEFER

[Greg Kroah-Hartman]

4.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Kuninori Morimoto <kuninori.morimoto.gx@xxxxxxxxxxx>

[ Upstream commit 6c92d5a2744e27619a8fcc9d74b91ee9f1cdebd1 ]

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@xxxxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 sound/soc/sh/rcar/core.c |   10 +++++++++-
 sound/soc/sh/rcar/dma.c  |    4 ++++
 2 files changed, 13 insertions(+), 1 deletion(-)

--- a/sound/soc/sh/rcar/core.c
+++ b/sound/soc/sh/rcar/core.c
@@ -482,7 +482,7 @@ static int rsnd_status_update(u32 *statu
 			(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);		\
@@ -1550,6 +1550,14 @@ 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;
 }
 
--- a/sound/soc/sh/rcar/dma.c
+++ b/sound/soc/sh/rcar/dma.c
@@ -244,6 +244,10 @@ static int rsnd_dmaen_attach(struct rsnd
 	/* 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