[PATCH v2] media: stm32-dcmi: fix lock scheme
From: Hugues Fruchet
Date: Thu Feb 22 2018 - 04:51:18 EST
Fix lock scheme leading to spurious freeze.
Signed-off-by: Hugues Fruchet <hugues.fruchet@xxxxxx>
---
version 2:
- dcmi_buf_queue() refactor to avoid to have "else" after "return"
(warning detected by checkpatch.pl --strict -f stm32-dcmi.c)
drivers/media/platform/stm32/stm32-dcmi.c | 57 +++++++++++++------------------
1 file changed, 24 insertions(+), 33 deletions(-)
diff --git a/drivers/media/platform/stm32/stm32-dcmi.c b/drivers/media/platform/stm32/stm32-dcmi.c
index 2fd8bed..5de18ad 100644
--- a/drivers/media/platform/stm32/stm32-dcmi.c
+++ b/drivers/media/platform/stm32/stm32-dcmi.c
@@ -197,7 +197,7 @@ static void dcmi_dma_callback(void *param)
struct dma_tx_state state;
enum dma_status status;
- spin_lock(&dcmi->irqlock);
+ spin_lock_irq(&dcmi->irqlock);
/* Check DMA status */
status = dmaengine_tx_status(chan, dcmi->dma_cookie, &state);
@@ -239,7 +239,7 @@ static void dcmi_dma_callback(void *param)
dcmi->errors_count++;
dcmi->active = NULL;
- spin_unlock(&dcmi->irqlock);
+ spin_unlock_irq(&dcmi->irqlock);
return;
}
@@ -248,13 +248,11 @@ static void dcmi_dma_callback(void *param)
list_del_init(&dcmi->active->list);
- if (dcmi_start_capture(dcmi)) {
+ spin_unlock_irq(&dcmi->irqlock);
+ if (dcmi_start_capture(dcmi))
dev_err(dcmi->dev, "%s: Cannot restart capture on DMA complete\n",
__func__);
-
- spin_unlock(&dcmi->irqlock);
- return;
- }
+ return;
}
break;
@@ -263,7 +261,7 @@ static void dcmi_dma_callback(void *param)
break;
}
- spin_unlock(&dcmi->irqlock);
+ spin_unlock_irq(&dcmi->irqlock);
}
static int dcmi_start_dma(struct stm32_dcmi *dcmi,
@@ -360,7 +358,7 @@ static irqreturn_t dcmi_irq_thread(int irq, void *arg)
{
struct stm32_dcmi *dcmi = arg;
- spin_lock(&dcmi->irqlock);
+ spin_lock_irq(&dcmi->irqlock);
/* Stop capture is required */
if (dcmi->state == STOPPING) {
@@ -370,7 +368,7 @@ static irqreturn_t dcmi_irq_thread(int irq, void *arg)
complete(&dcmi->complete);
- spin_unlock(&dcmi->irqlock);
+ spin_unlock_irq(&dcmi->irqlock);
return IRQ_HANDLED;
}
@@ -383,35 +381,34 @@ static irqreturn_t dcmi_irq_thread(int irq, void *arg)
__func__);
dcmi->errors_count++;
- dmaengine_terminate_all(dcmi->dma_chan);
-
dev_dbg(dcmi->dev, "Restarting capture after DCMI error\n");
- if (dcmi_start_capture(dcmi)) {
+ spin_unlock_irq(&dcmi->irqlock);
+ dmaengine_terminate_all(dcmi->dma_chan);
+
+ if (dcmi_start_capture(dcmi))
dev_err(dcmi->dev, "%s: Cannot restart capture on overflow or error\n",
__func__);
-
- spin_unlock(&dcmi->irqlock);
- return IRQ_HANDLED;
- }
+ return IRQ_HANDLED;
}
- spin_unlock(&dcmi->irqlock);
+ spin_unlock_irq(&dcmi->irqlock);
return IRQ_HANDLED;
}
static irqreturn_t dcmi_irq_callback(int irq, void *arg)
{
struct stm32_dcmi *dcmi = arg;
+ unsigned long flags;
- spin_lock(&dcmi->irqlock);
+ spin_lock_irqsave(&dcmi->irqlock, flags);
dcmi->misr = reg_read(dcmi->regs, DCMI_MIS);
/* Clear interrupt */
reg_set(dcmi->regs, DCMI_ICR, IT_FRAME | IT_OVR | IT_ERR);
- spin_unlock(&dcmi->irqlock);
+ spin_unlock_irqrestore(&dcmi->irqlock, flags);
return IRQ_WAKE_THREAD;
}
@@ -490,9 +487,8 @@ static void dcmi_buf_queue(struct vb2_buffer *vb)
struct stm32_dcmi *dcmi = vb2_get_drv_priv(vb->vb2_queue);
struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
struct dcmi_buf *buf = container_of(vbuf, struct dcmi_buf, vb);
- unsigned long flags = 0;
- spin_lock_irqsave(&dcmi->irqlock, flags);
+ spin_lock_irq(&dcmi->irqlock);
if ((dcmi->state == RUNNING) && (!dcmi->active)) {
dcmi->active = buf;
@@ -500,19 +496,15 @@ static void dcmi_buf_queue(struct vb2_buffer *vb)
dev_dbg(dcmi->dev, "Starting capture on buffer[%d] queued\n",
buf->vb.vb2_buf.index);
- if (dcmi_start_capture(dcmi)) {
+ spin_unlock_irq(&dcmi->irqlock);
+ if (dcmi_start_capture(dcmi))
dev_err(dcmi->dev, "%s: Cannot restart capture on overflow or error\n",
__func__);
-
- spin_unlock_irqrestore(&dcmi->irqlock, flags);
- return;
- }
} else {
/* Enqueue to video buffers list */
list_add_tail(&buf->list, &dcmi->buffers);
+ spin_unlock_irq(&dcmi->irqlock);
}
-
- spin_unlock_irqrestore(&dcmi->irqlock, flags);
}
static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
@@ -598,20 +590,17 @@ static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
dev_dbg(dcmi->dev, "Start streaming, starting capture\n");
+ spin_unlock_irq(&dcmi->irqlock);
ret = dcmi_start_capture(dcmi);
if (ret) {
dev_err(dcmi->dev, "%s: Start streaming failed, cannot start capture\n",
__func__);
-
- spin_unlock_irq(&dcmi->irqlock);
goto err_subdev_streamoff;
}
/* Enable interruptions */
reg_set(dcmi->regs, DCMI_IER, IT_FRAME | IT_OVR | IT_ERR);
- spin_unlock_irq(&dcmi->irqlock);
-
return 0;
err_subdev_streamoff:
@@ -654,7 +643,9 @@ static void dcmi_stop_streaming(struct vb2_queue *vq)
dev_err(dcmi->dev, "%s: Failed to stop streaming, subdev streamoff error (%d)\n",
__func__, ret);
+ spin_lock_irq(&dcmi->irqlock);
dcmi->state = STOPPING;
+ spin_unlock_irq(&dcmi->irqlock);
timeout = wait_for_completion_interruptible_timeout(&dcmi->complete,
time_ms);
--
1.9.1