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ASoC: stm32: spdifrx: fix inconsistent lock state

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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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Olivier Moysan 2019-12-04 16:43:31 +01:00 committed by Greg Kroah-Hartman
parent d070b8d570
commit 42182bcccd
1 changed files with 7 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
sound/soc/stm/stm32_spdifrx.c
View File

@ -313,6 +313,7 @@ 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;
@ -320,7 +321,7 @@ 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++;
@ -353,7 +354,7 @@ 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;
}
@ -361,11 +362,12 @@ 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;
}
@ -384,7 +386,7 @@ 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,