From: Kuninori Morimoto kuninori.morimoto.gx@renesas.com
[ Upstream commit a122a116fc6d8fcf2f202dcd185173a54268f239 ]
Current rsnd needs to call .prepare (P) for clock settings, .trigger for playback start (S) and stop (E). It should be called as below from SSI point of view.
P -> S -> E -> P -> S -> E -> ...
But, if you used MIXer, below case might happen
(2) 1: P -> S ---> E -> ... 2: P ----> S -> ... (1) (3)
P(1) setups clock, but E(2) resets it. and starts playback (3). In such case, it will reports "SSI parent/child should use same rate".
rsnd_ssi_master_clk_start() which is the main function at (P) was called from rsnd_ssi_init() (= S) before, but was moved by below patch to rsnd_soc_dai_prepare() (= P) to avoid using clk_get_rate() which shouldn't be used under atomic context.
commit 4d230d1271064 ("ASoC: rsnd: fixup not to call clk_get/set under non-atomic")
Because of above patch, rsnd_ssi_master_clk_start() is now called at (P) which is for non atomic context. But (P) is assuming that spin lock is *not* used. One issue now is rsnd_ssi_master_clk_start() is checking ssi->xxx which should be protected by spin lock.
After above patch, adg.c had below patch for other reasons.
commit 06e8f5c842f2d ("ASoC: rsnd: don't call clk_get_rate() under atomic context")
clk_get_rate() is used at probe() timing by this patch. In other words, rsnd_ssi_master_clk_start() is no longer using clk_get_rate() any more.
This means we can call it from rsnd_ssi_init() (= S) again which is protected by spin lock. This patch re-move it to under spin lock, and solves 1. checking ssi->xxx without spin lock issue. 2. clk setting / device start / device stop race condition.
Reported-by: Linh Phung T. Y. linh.phung.jy@renesas.com Signed-off-by: Kuninori Morimoto kuninori.morimoto.gx@renesas.com Link: https://lore.kernel.org/r/875z0x1jt5.wl-kuninori.morimoto.gx@renesas.com Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- sound/soc/sh/rcar/ssi.c | 14 +++++--------- 1 file changed, 5 insertions(+), 9 deletions(-)
diff --git a/sound/soc/sh/rcar/ssi.c b/sound/soc/sh/rcar/ssi.c index 47d5ddb526f2..8926dd69e8b8 100644 --- a/sound/soc/sh/rcar/ssi.c +++ b/sound/soc/sh/rcar/ssi.c @@ -507,10 +507,15 @@ static int rsnd_ssi_init(struct rsnd_mod *mod, struct rsnd_priv *priv) { struct rsnd_ssi *ssi = rsnd_mod_to_ssi(mod); + int ret;
if (!rsnd_ssi_is_run_mods(mod, io)) return 0;
+ ret = rsnd_ssi_master_clk_start(mod, io); + if (ret < 0) + return ret; + ssi->usrcnt++;
rsnd_mod_power_on(mod); @@ -1060,13 +1065,6 @@ static int rsnd_ssi_pio_pointer(struct rsnd_mod *mod, return 0; }
-static int rsnd_ssi_prepare(struct rsnd_mod *mod, - struct rsnd_dai_stream *io, - struct rsnd_priv *priv) -{ - return rsnd_ssi_master_clk_start(mod, io); -} - static struct rsnd_mod_ops rsnd_ssi_pio_ops = { .name = SSI_NAME, .probe = rsnd_ssi_common_probe, @@ -1079,7 +1077,6 @@ static struct rsnd_mod_ops rsnd_ssi_pio_ops = { .pointer = rsnd_ssi_pio_pointer, .pcm_new = rsnd_ssi_pcm_new, .hw_params = rsnd_ssi_hw_params, - .prepare = rsnd_ssi_prepare, .get_status = rsnd_ssi_get_status, };
@@ -1166,7 +1163,6 @@ static struct rsnd_mod_ops rsnd_ssi_dma_ops = { .pcm_new = rsnd_ssi_pcm_new, .fallback = rsnd_ssi_fallback, .hw_params = rsnd_ssi_hw_params, - .prepare = rsnd_ssi_prepare, .get_status = rsnd_ssi_get_status, };