Modules failing to stop are fatal errors for the preview engine only.
Flag that condition separately from the other stop failures to prepare
support for more fatal errors.
Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
---
drivers/media/platform/omap3isp/isp.c | 36 +++++++++++++++++++++--------------
drivers/media/platform/omap3isp/isp.h | 2 ++
2 files changed, 24 insertions(+), 14 deletions(-)
diff --git a/drivers/media/platform/omap3isp/isp.c b/drivers/media/platform/omap3isp/isp.c
index 7e09c1d..5807185 100644
--- a/drivers/media/platform/omap3isp/isp.c
+++ b/drivers/media/platform/omap3isp/isp.c
@@ -873,15 +873,12 @@ static int isp_pipeline_enable(struct isp_pipeline *pipe,
unsigned long flags;
int ret;
- /* If the preview engine crashed it might not respond to read/write
- * operations on the L4 bus. This would result in a bus fault and a
- * kernel oops. Refuse to start streaming in that case. This check must
- * be performed before the loop below to avoid starting entities if the
- * pipeline won't start anyway (those entities would then likely fail to
- * stop, making the problem worse).
+ /* Refuse to start streaming if an entity included in the pipeline has
+ * crashed. This check must be performed before the loop below to avoid
+ * starting entities if the pipeline won't start anyway (those entities
+ * would then likely fail to stop, making the problem worse).
*/
- if ((pipe->entities & isp->crashed) &
- (1U << isp->isp_prev.subdev.entity.id))
+ if (pipe->entities & isp->crashed)
return -EIO;
spin_lock_irqsave(&pipe->lock, flags);
@@ -1014,13 +1011,23 @@ static int isp_pipeline_disable(struct isp_pipeline *pipe)
else
ret = 0;
+ /* Handle stop failures. An entity that fails to stop can
+ * usually just be restarted. Flag the stop failure nonetheless
+ * to trigger an ISP reset the next time the device is released,
+ * just in case.
+ *
+ * The preview engine is a special case. A failure to stop can
+ * mean a hardware crash. When that happens the preview engine
+ * won't respond to read/write operations on the L4 bus anymore,
+ * resulting in a bus fault and a kernel oops next time it gets
+ * accessed. Mark it as crashed to prevent pipelines including
+ * it from being started.
+ */
if (ret) {
dev_info(isp->dev, "Unable to stop %s\n", subdev->name);
- /* If the entity failed to stopped, assume it has
- * crashed. Mark it as such, the ISP will be reset when
- * applications will release it.
- */
- isp->crashed |= 1U << subdev->entity.id;
+ isp->stop_failure = true;
+ if (subdev == &isp->isp_prev.subdev)
+ isp->crashed |= 1U << subdev->entity.id;
failure = -ETIMEDOUT;
}
}
@@ -1225,6 +1232,7 @@ static int isp_reset(struct isp_device *isp)
udelay(1);
}
+ isp->stop_failure = false;
isp->crashed = 0;
return 0;
}
@@ -1636,7 +1644,7 @@ void omap3isp_put(struct isp_device *isp)
/* Reset the ISP if an entity has failed to stop. This is the
* only way to recover from such conditions.
*/
- if (isp->crashed)
+ if (isp->crashed || isp->stop_failure)
isp_reset(isp);
isp_disable_clocks(isp);
}
diff --git a/drivers/media/platform/omap3isp/isp.h b/drivers/media/platform/omap3isp/isp.h
index 5b91f86..081f5ec 100644
--- a/drivers/media/platform/omap3isp/isp.h
+++ b/drivers/media/platform/omap3isp/isp.h
@@ -154,6 +154,7 @@ struct isp_xclk {
* regions.
* @stat_lock: Spinlock for handling statistics
* @isp_mutex: Mutex for serializing requests to ISP.
+ * @stop_failure: Indicates that an entity failed to stop.
* @crashed: Bitmask of crashed entities (indexed by entity ID)
* @has_context: Context has been saved at least once and can be restored.
* @ref_count: Reference count for handling multiple ISP requests.
@@ -191,6 +192,7 @@ struct isp_device {
/* ISP Obj */
spinlock_t stat_lock; /* common lock for statistic drivers */
struct mutex isp_mutex; /* For handling ref_count field */
+ bool stop_failure;
u32 crashed;
int has_context;
int ref_count;
--
1.8.3.2
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