diff mbox series

[v15,07/19] media: subdev: add v4l2_subdev_set_routing helper()

Message ID 20221003121852.616745-8-tomi.valkeinen@ideasonboard.com
State Superseded
Headers show
Series v4l: routing and streams support | expand

Commit Message

Tomi Valkeinen Oct. 3, 2022, 12:18 p.m. UTC
Add a helper function to set the subdev routing. The helper can be used
from subdev driver's set_routing op to store the routing table.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
---
 drivers/media/v4l2-core/v4l2-subdev.c | 31 +++++++++++++++++++++++++++
 include/media/v4l2-subdev.h           | 16 ++++++++++++++
 2 files changed, 47 insertions(+)

Comments

Tomi Valkeinen Oct. 12, 2022, 6:58 a.m. UTC | #1
On 12/10/2022 09:22, Yunke Cao wrote:
> Hi Tomi,
> 
> On Wed, Oct 12, 2022 at 2:03 PM Tomi Valkeinen
> <tomi.valkeinen@ideasonboard.com> wrote:
>>
>> Add a helper function to set the subdev routing. The helper can be used
>> from subdev driver's set_routing op to store the routing table.
>>
>> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
>> Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
>> ---
>>   drivers/media/v4l2-core/v4l2-subdev.c | 31 +++++++++++++++++++++++++++
>>   include/media/v4l2-subdev.h           | 16 ++++++++++++++
>>   2 files changed, 47 insertions(+)
>>
>> diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
>> index fff17b8536fc..3ae4f39a50e4 100644
>> --- a/drivers/media/v4l2-core/v4l2-subdev.c
>> +++ b/drivers/media/v4l2-core/v4l2-subdev.c
>> @@ -12,6 +12,7 @@
>>   #include <linux/ioctl.h>
>>   #include <linux/mm.h>
>>   #include <linux/module.h>
>> +#include <linux/overflow.h>
>>   #include <linux/slab.h>
>>   #include <linux/types.h>
>>   #include <linux/version.h>
>> @@ -1181,6 +1182,36 @@ int v4l2_subdev_get_fmt(struct v4l2_subdev *sd, struct v4l2_subdev_state *state,
>>   }
>>   EXPORT_SYMBOL_GPL(v4l2_subdev_get_fmt);
>>
>> +int v4l2_subdev_set_routing(struct v4l2_subdev *sd,
>> +                           struct v4l2_subdev_state *state,
>> +                           const struct v4l2_subdev_krouting *routing)
>> +{
>> +       struct v4l2_subdev_krouting *dst = &state->routing;
>> +       const struct v4l2_subdev_krouting *src = routing;
>> +       struct v4l2_subdev_krouting new_routing = { 0 };
>> +       size_t bytes;
>> +
>> +       if (unlikely(check_mul_overflow(src->num_routes, sizeof(*src->routes),
> 
> Do we need to cast (size_t)src->num_routes here?
> My compiler is complaining:
> ./include/linux/overflow.h:85:22: error: comparison of distinct
> pointer types lacks a cast [-Werror]
>     85 |         (void) (&__a == &__b);                  \
> 

Yes, I think we should do that. Thanks! I need to remember to compile 
with other compilers than arm32 too =).

  Tomi
diff mbox series

Patch

diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
index fff17b8536fc..3ae4f39a50e4 100644
--- a/drivers/media/v4l2-core/v4l2-subdev.c
+++ b/drivers/media/v4l2-core/v4l2-subdev.c
@@ -12,6 +12,7 @@ 
 #include <linux/ioctl.h>
 #include <linux/mm.h>
 #include <linux/module.h>
+#include <linux/overflow.h>
 #include <linux/slab.h>
 #include <linux/types.h>
 #include <linux/version.h>
@@ -1181,6 +1182,36 @@  int v4l2_subdev_get_fmt(struct v4l2_subdev *sd, struct v4l2_subdev_state *state,
 }
 EXPORT_SYMBOL_GPL(v4l2_subdev_get_fmt);
 
+int v4l2_subdev_set_routing(struct v4l2_subdev *sd,
+			    struct v4l2_subdev_state *state,
+			    const struct v4l2_subdev_krouting *routing)
+{
+	struct v4l2_subdev_krouting *dst = &state->routing;
+	const struct v4l2_subdev_krouting *src = routing;
+	struct v4l2_subdev_krouting new_routing = { 0 };
+	size_t bytes;
+
+	if (unlikely(check_mul_overflow(src->num_routes, sizeof(*src->routes),
+					&bytes)))
+		return -EOVERFLOW;
+
+	lockdep_assert_held(state->lock);
+
+	if (src->num_routes > 0) {
+		new_routing.routes = kmemdup(src->routes, bytes, GFP_KERNEL);
+		if (!new_routing.routes)
+			return -ENOMEM;
+	}
+
+	new_routing.num_routes = src->num_routes;
+
+	kfree(dst->routes);
+	*dst = new_routing;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(v4l2_subdev_set_routing);
+
 #endif /* CONFIG_VIDEO_V4L2_SUBDEV_API */
 
 #endif /* CONFIG_MEDIA_CONTROLLER */
diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
index 45c41f4d6a2b..7962e6572bda 100644
--- a/include/media/v4l2-subdev.h
+++ b/include/media/v4l2-subdev.h
@@ -1419,6 +1419,22 @@  v4l2_subdev_lock_and_get_active_state(struct v4l2_subdev *sd)
 int v4l2_subdev_get_fmt(struct v4l2_subdev *sd, struct v4l2_subdev_state *state,
 			struct v4l2_subdev_format *format);
 
+/**
+ * v4l2_subdev_set_routing() - Set given routing to subdev state
+ * @sd: The subdevice
+ * @state: The subdevice state
+ * @routing: Routing that will be copied to subdev state
+ *
+ * This will release old routing table (if any) from the state, allocate
+ * enough space for the given routing, and copy the routing.
+ *
+ * This can be used from the subdev driver's set_routing op, after validating
+ * the routing.
+ */
+int v4l2_subdev_set_routing(struct v4l2_subdev *sd,
+			    struct v4l2_subdev_state *state,
+			    const struct v4l2_subdev_krouting *routing);
+
 #endif /* CONFIG_VIDEO_V4L2_SUBDEV_API */
 
 #endif /* CONFIG_MEDIA_CONTROLLER */