blob: 9d2348c4bd02349f2d77fe02c4615c2e9c6fc494 [file] [log] [blame]
From 5804c288baa8496a8c01433eee5ca0702129ba01 Mon Sep 17 00:00:00 2001
From: Olivier Moysan <olivier.moysan@st.com>
Date: Wed, 4 Dec 2019 16:43:31 +0100
Subject: [PATCH] ASoC: stm32: spdifrx: fix inconsistent lock state
commit 2859b1784031b5709446af8f6039c467f136e67d upstream.
In current spdifrx driver locks may be requested as follows:
- request lock on iec capture control, when starting synchronization.
- request lock in interrupt context, when spdifrx stop is called
from IRQ handler.
Take lock with IRQs disabled, to avoid the possible deadlock.
Lockdep report:
[ 74.278059] ================================
[ 74.282306] WARNING: inconsistent lock state
[ 74.290120] --------------------------------
...
[ 74.314373] CPU0
[ 74.314377] ----
[ 74.314381] lock(&(&spdifrx->lock)->rlock);
[ 74.314396] <Interrupt>
[ 74.314400] lock(&(&spdifrx->lock)->rlock);
Fixes: 03e4d5d56fa5 ("ASoC: stm32: Add SPDIFRX support")
Signed-off-by: Olivier Moysan <olivier.moysan@st.com>
Link: https://lore.kernel.org/r/20191204154333.7152-2-olivier.moysan@st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
diff --git a/sound/soc/stm/stm32_spdifrx.c b/sound/soc/stm/stm32_spdifrx.c
index 56d79695577c..0ef0bec4009a 100644
--- a/sound/soc/stm/stm32_spdifrx.c
+++ b/sound/soc/stm/stm32_spdifrx.c
@@ -304,6 +304,7 @@ static void stm32_spdifrx_dma_ctrl_stop(struct stm32_spdifrx_data *spdifrx)
static int stm32_spdifrx_start_sync(struct stm32_spdifrx_data *spdifrx)
{
int cr, cr_mask, imr, ret;
+ unsigned long flags;
/* Enable IRQs */
imr = SPDIFRX_IMR_IFEIE | SPDIFRX_IMR_SYNCDIE | SPDIFRX_IMR_PERRIE;
@@ -311,7 +312,7 @@ static int stm32_spdifrx_start_sync(struct stm32_spdifrx_data *spdifrx)
if (ret)
return ret;
- spin_lock(&spdifrx->lock);
+ spin_lock_irqsave(&spdifrx->lock, flags);
spdifrx->refcount++;
@@ -344,7 +345,7 @@ static int stm32_spdifrx_start_sync(struct stm32_spdifrx_data *spdifrx)
"Failed to start synchronization\n");
}
- spin_unlock(&spdifrx->lock);
+ spin_unlock_irqrestore(&spdifrx->lock, flags);
return ret;
}
@@ -352,11 +353,12 @@ static int stm32_spdifrx_start_sync(struct stm32_spdifrx_data *spdifrx)
static void stm32_spdifrx_stop(struct stm32_spdifrx_data *spdifrx)
{
int cr, cr_mask, reg;
+ unsigned long flags;
- spin_lock(&spdifrx->lock);
+ spin_lock_irqsave(&spdifrx->lock, flags);
if (--spdifrx->refcount) {
- spin_unlock(&spdifrx->lock);
+ spin_unlock_irqrestore(&spdifrx->lock, flags);
return;
}
@@ -375,7 +377,7 @@ static void stm32_spdifrx_stop(struct stm32_spdifrx_data *spdifrx)
regmap_read(spdifrx->regmap, STM32_SPDIFRX_DR, &reg);
regmap_read(spdifrx->regmap, STM32_SPDIFRX_CSR, &reg);
- spin_unlock(&spdifrx->lock);
+ spin_unlock_irqrestore(&spdifrx->lock, flags);
}
static int stm32_spdifrx_dma_ctrl_register(struct device *dev,
--
2.7.4