diff mbox series

[v6,14/14] media: vivid: add cache_hints module param

Message ID 20200514160153.3646-15-sergey.senozhatsky@gmail.com
State New
Headers show
Series Implement V4L2_BUF_FLAG_NO_CACHE_* flags | expand

Commit Message

Sergey Senozhatsky May 14, 2020, 4:01 p.m. UTC 
From: Sergey Senozhatsky <senozhatsky@chromium.org>

Add a cache_hints module param to control per-queue user space cache
hints support.

Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
---
 Documentation/admin-guide/media/vivid.rst     | 9 +++++++++
 drivers/media/test-drivers/vivid/vivid-core.c | 9 +++++++++
 2 files changed, 18 insertions(+)
diff mbox series

Patch

diff --git a/Documentation/admin-guide/media/vivid.rst b/Documentation/admin-guide/media/vivid.rst
index 52e57b773f07..6d7175f96f74 100644
--- a/Documentation/admin-guide/media/vivid.rst
+++ b/Documentation/admin-guide/media/vivid.rst
@@ -293,6 +293,15 @@  all configurable using the following module options:
 		- 0: vmalloc
 		- 1: dma-contig
 
+- cache_hints:
+
+	specifies if the device should set queues' user-space cache and memory
+	consistency hint capability (V4L2_BUF_CAP_SUPPORTS_MMAP_CACHE_HINTS).
+	The hints are valid only when using MMAP streaming I/O. Default is 0.
+
+		- 0: forbid hints
+		- 1: allow hints
+
 Taken together, all these module options allow you to precisely customize
 the driver behavior and test your application with all sorts of permutations.
 It is also very suitable to emulate hardware that is not yet available, e.g.
diff --git a/drivers/media/test-drivers/vivid/vivid-core.c b/drivers/media/test-drivers/vivid/vivid-core.c
index 6c740e3e6999..5c986df4a8d4 100644
--- a/drivers/media/test-drivers/vivid/vivid-core.c
+++ b/drivers/media/test-drivers/vivid/vivid-core.c
@@ -169,6 +169,14 @@  MODULE_PARM_DESC(allocators, " memory allocator selection, default is 0.\n"
 			     "\t\t    0 == vmalloc\n"
 			     "\t\t    1 == dma-contig");
 
+static unsigned int cache_hints[VIVID_MAX_DEVS] = {
+	[0 ... (VIVID_MAX_DEVS - 1)] = 0
+};
+module_param_array(cache_hints, uint, NULL, 0444);
+MODULE_PARM_DESC(cache_hints, " user-space cache hints, default is 0.\n"
+			     "\t\t    0 == forbid\n"
+			     "\t\t    1 == allow");
+
 static struct vivid_dev *vivid_devs[VIVID_MAX_DEVS];
 
 const struct v4l2_rect vivid_min_rect = {
@@ -819,6 +827,7 @@  static int vivid_create_queue(struct vivid_dev *dev,
 	q->lock = &dev->mutex;
 	q->dev = dev->v4l2_dev.dev;
 	q->supports_requests = true;
+	q->allow_cache_hints = (cache_hints[dev->inst] == 1);
 
 	return vb2_queue_init(q);
 }