@@ -177,6 +177,15 @@ MODULE_PARM_DESC(cache_hints, " user-space cache hints, default is 0.\n"
"\t\t 0 == forbid\n"
"\t\t 1 == allow");
+static unsigned int supports_requests[VIVID_MAX_DEVS] = {
+ [0 ... (VIVID_MAX_DEVS - 1)] = 1
+};
+module_param_array(supports_requests, uint, NULL, 0444);
+MODULE_PARM_DESC(supports_requests, " support for requests, default is 1.\n"
+ "\t\t 0 == no support\n"
+ "\t\t 1 == supports requests\n"
+ "\t\t 2 == requires requests");
+
static struct vivid_dev *vivid_devs[VIVID_MAX_DEVS];
const struct v4l2_rect vivid_min_rect = {
@@ -883,10 +892,11 @@ static int vivid_create_queue(struct vivid_dev *dev,
q->mem_ops = allocators[dev->inst] == 1 ? &vb2_dma_contig_memops :
&vb2_vmalloc_memops;
q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
- q->min_buffers_needed = min_buffers_needed;
+ q->min_buffers_needed = supports_requests[dev->inst] ? 0 : min_buffers_needed;
q->lock = &dev->mutex;
q->dev = dev->v4l2_dev.dev;
- q->supports_requests = true;
+ q->supports_requests = supports_requests[dev->inst];
+ q->requires_requests = supports_requests[dev->inst] >= 2;
q->allow_cache_hints = (cache_hints[dev->inst] == 1);
return vb2_queue_init(q);
Currently vivid supports the Request API, but it also sets min_buffers_needed in the vb2 queue. But the combination of support_requests and min_buffers_needed is not allowed due to the fact that vb2_core_qbuf() isn't supposed to fail when called from the request framework. And if min_buffers_needed > 0, then is can call start_streaming() which definitely can fail. With the new module option you can control if requests are not allowed (min_buffers_needed is 2 in that case), optionally allowed or are required. In the latter two cases min_buffers_needed is set to 0. Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> --- drivers/media/test-drivers/vivid/vivid-core.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-)