video: adf: support "simple" buffers

Simple buffers are linear RGB buffers analogous to KMS's dumb buffers.
Simple buffers can be allocated and posted to a display interface
without any driver-private data.

Internally, ADF drivers provide the driver-private data needed (if any)
to post a simple buffer to the display.

Change-Id: Ib0b737622eaf343111310f6623f99d69cf3807d2
Signed-off-by: Greg Hackmann <ghackmann@google.com>

5 files changed, 231 insertions, 0 deletions

diff --git a/drivers/video/adf/adf_client.c b/drivers/video/adf/adf_client.c
index f52b29d1a9a..48e97ef262f 100644
--- a/drivers/video/adf/adf_client.c
+++ b/drivers/video/adf/adf_client.c
@@ -762,3 +762,81 @@ done:
 	return ret;
 }
 EXPORT_SYMBOL(adf_device_detach);
+
+/**
+ * adf_interface_simple_buffer_alloc - allocate a simple buffer
+ *
+ * @intf: target interface
+ * @w: width in pixels
+ * @h: height in pixels
+ * @format: format fourcc
+ * @dma_buf: returns the allocated buffer
+ * @offset: returns the byte offset of the allocated buffer's first pixel
+ * @pitch: returns the allocated buffer's pitch
+ *
+ * See &struct adf_simple_buffer_alloc for a description of simple buffers and
+ * their limitations.
+ *
+ * Returns 0 on success or -errno on failure.
+ */
+int adf_interface_simple_buffer_alloc(struct adf_interface *intf, u16 w, u16 h,
+		u32 format, struct dma_buf **dma_buf, u32 *offset, u32 *pitch)
+{
+	if (!intf->ops || !intf->ops->alloc_simple_buffer)
+		return -EOPNOTSUPP;
+
+	if (!adf_format_is_rgb(format))
+		return -EINVAL;
+
+	return intf->ops->alloc_simple_buffer(intf, w, h, format, dma_buf,
+			offset, pitch);
+}
+EXPORT_SYMBOL(adf_interface_simple_buffer_alloc);
+
+/**
+ * adf_interface_simple_post - flip to a single buffer
+ *
+ * @intf: interface targeted by the flip
+ * @buf: buffer to display
+ *
+ * adf_interface_simple_post() can be used generically for simple display
+ * configurations, since the client does not need to provide any driver-private
+ * configuration data.
+ *
+ * adf_interface_simple_post() has the same copying semantics as
+ * adf_device_post().
+ *
+ * On success, returns a sync fence which signals when the buffer is removed
+ * from the screen.  On failure, returns ERR_PTR(-errno).
+ */
+struct sync_fence *adf_interface_simple_post(struct adf_interface *intf,
+		struct adf_buffer *buf)
+{
+	size_t custom_data_size = 0;
+	void *custom_data = NULL;
+	struct sync_fence *ret;
+
+	if (intf->ops && intf->ops->describe_simple_post) {
+		int err;
+
+		custom_data = kzalloc(ADF_MAX_CUSTOM_DATA_SIZE, GFP_KERNEL);
+		if (!custom_data) {
+			ret = ERR_PTR(-ENOMEM);
+			goto done;
+		}
+
+		err = intf->ops->describe_simple_post(intf, buf, custom_data,
+				&custom_data_size);
+		if (err < 0) {
+			ret = ERR_PTR(err);
+			goto done;
+		}
+	}
+
+	ret = adf_device_post(adf_interface_parent(intf), &intf, 1, buf, 1,
+			custom_data, custom_data_size);
+done:
+	kfree(custom_data);
+	return ret;
+}
+EXPORT_SYMBOL(adf_interface_simple_post);
diff --git a/drivers/video/adf/adf_fops.c b/drivers/video/adf/adf_fops.c
index 90b234a7666..d2e30c9cddc 100644
--- a/drivers/video/adf/adf_fops.c
+++ b/drivers/video/adf/adf_fops.c
@@ -310,6 +310,79 @@ err_get_user:
 	return ret;
 }
 
+static int adf_intf_simple_post_config(struct adf_interface *intf,
+		struct adf_simple_post_config __user *arg)
+{
+	struct adf_device *dev = intf->base.parent;
+	struct sync_fence *complete_fence;
+	int complete_fence_fd;
+	struct adf_buffer buf;
+	int ret = 0;
+
+	complete_fence_fd = get_unused_fd();
+	if (complete_fence_fd < 0)
+		return complete_fence_fd;
+
+	ret = adf_buffer_import(dev, &arg->buf, &buf);
+	if (ret < 0)
+		goto err_import;
+
+	if (put_user(complete_fence_fd, &arg->complete_fence)) {
+		ret = -EFAULT;
+		goto err_put_user;
+	}
+
+	complete_fence = adf_interface_simple_post(intf, &buf);
+	if (IS_ERR(complete_fence)) {
+		ret = PTR_ERR(complete_fence);
+		goto err_put_user;
+	}
+
+	sync_fence_install(complete_fence, complete_fence_fd);
+	return 0;
+
+err_put_user:
+	adf_buffer_cleanup(&buf);
+err_import:
+	put_unused_fd(complete_fence_fd);
+	return ret;
+}
+
+static int adf_intf_simple_buffer_alloc(struct adf_interface *intf,
+		struct adf_simple_buffer_alloc __user *arg)
+{
+	struct adf_simple_buffer_alloc data;
+	struct dma_buf *dma_buf;
+	int ret = 0;
+
+	if (copy_from_user(&data, arg, sizeof(data)))
+		return -EFAULT;
+
+	data.fd = get_unused_fd_flags(O_CLOEXEC);
+	if (data.fd < 0)
+		return data.fd;
+
+	ret = adf_interface_simple_buffer_alloc(intf, data.w, data.h,
+			data.format, &dma_buf, &data.offset, &data.pitch);
+	if (ret < 0)
+		goto err_alloc;
+
+	if (copy_to_user(arg, &data, sizeof(*arg))) {
+		ret = -EFAULT;
+		goto err_copy;
+	}
+
+	fd_install(data.fd, dma_buf->file);
+	return 0;
+
+err_copy:
+	dma_buf_put(dma_buf);
+
+err_alloc:
+	put_unused_fd(data.fd);
+	return ret;
+}
+
 static int adf_copy_attachment_list_to_user(
 		struct adf_attachment_config __user *to, size_t n_to,
 		struct adf_attachment *from, size_t n_from)
@@ -539,6 +612,8 @@ static long adf_overlay_engine_ioctl(struct adf_overlay_engine *eng,
 	case ADF_SET_MODE:
 	case ADF_GET_DEVICE_DATA:
 	case ADF_GET_INTERFACE_DATA:
+	case ADF_SIMPLE_POST_CONFIG:
+	case ADF_SIMPLE_BUFFER_ALLOC:
 	case ADF_ATTACH:
 	case ADF_DETACH:
 		return -EINVAL;
@@ -567,6 +642,14 @@ static long adf_interface_ioctl(struct adf_interface *intf,
 		return adf_intf_get_data(intf,
 				(struct adf_interface_data __user *)arg);
 
+	case ADF_SIMPLE_POST_CONFIG:
+		return adf_intf_simple_post_config(intf,
+				(struct adf_simple_post_config __user *)arg);
+
+	case ADF_SIMPLE_BUFFER_ALLOC:
+		return adf_intf_simple_buffer_alloc(intf,
+				(struct adf_simple_buffer_alloc __user *)arg);
+
 	case ADF_POST_CONFIG:
 	case ADF_GET_DEVICE_DATA:
 	case ADF_GET_OVERLAY_ENGINE_DATA:
@@ -609,6 +692,8 @@ static long adf_device_ioctl(struct adf_device *dev, struct adf_file *file,
 	case ADF_SET_MODE:
 	case ADF_GET_INTERFACE_DATA:
 	case ADF_GET_OVERLAY_ENGINE_DATA:
+	case ADF_SIMPLE_POST_CONFIG:
+	case ADF_SIMPLE_BUFFER_ALLOC:
 		return -EINVAL;
 
 	default:
diff --git a/include/uapi/video/adf.h b/include/uapi/video/adf.h
index 757465b8b58..4b9e60c84e6 100644
--- a/include/uapi/video/adf.h
+++ b/include/uapi/video/adf.h
@@ -152,6 +152,50 @@ struct adf_post_config {
 #define ADF_MAX_INTERFACES (PAGE_SIZE / sizeof(__u32))
 
 /**
+ * struct adf_simple_buffer_allocate - request to allocate a "simple" buffer
+ *
+ * @w: width of buffer in pixels (input)
+ * @h: height of buffer in pixels (input)
+ * @format: DRM-style fourcc (input)
+ *
+ * @fd: dma_buf fd (output)
+ * @offset: location of first pixel, in bytes (output)
+ * @pitch: length of a scanline including padding, in bytes (output)
+ *
+ * Simple buffers are analogous to DRM's "dumb" buffers.  They have a single
+ * plane of linear RGB data which can be allocated and scanned out without
+ * any driver-private ioctls or data.
+ *
+ * @format must be a standard RGB format defined in drm_fourcc.h.
+ *
+ * ADF clients must NOT assume that an interface can scan out a simple buffer
+ * allocated by a different ADF interface, even if the two interfaces belong to
+ * the same ADF device.
+ */
+struct adf_simple_buffer_alloc {
+	__u16 w;
+	__u16 h;
+	__u32 format;
+
+	__s64 fd;
+	__u32 offset;
+	__u32 pitch;
+};
+
+/**
+ * struct adf_simple_post_config - request to flip to a single buffer without
+ * driver-private data
+ *
+ * @buf: description of buffer displayed (input)
+ * @complete_fence: sync_fence fd which will clear when this buffer has left the
+ * screen (output)
+ */
+struct adf_simple_post_config {
+	struct adf_buffer_config buf;
+	__s64 complete_fence;
+};
+
+/**
  * struct adf_attachment_config - description of attachment between an overlay
  * engine and an interface
  *
@@ -248,6 +292,8 @@ struct adf_overlay_engine_data {
 #define ADF_GET_INTERFACE_DATA	_IOR('D', 5, struct adf_interface_data)
 #define ADF_GET_OVERLAY_ENGINE_DATA \
 				_IOR('D', 6, struct adf_overlay_engine_data)
+#define ADF_SIMPLE_POST_CONFIG	_IOW('D', 7, struct adf_simple_post_config)
+#define ADF_SIMPLE_BUFFER_ALLOC	_IOW('D', 8, struct adf_simple_buffer_alloc)
 #define ADF_ATTACH		_IOW('D', 9, struct adf_attachment_config)
 #define ADF_DETACH		_IOW('D', 10, struct adf_attachment_config)
 
diff --git a/include/video/adf.h b/include/video/adf.h
index c09d8dfb4d6..6c2191a318a 100644
--- a/include/video/adf.h
+++ b/include/video/adf.h
@@ -299,6 +299,16 @@ struct adf_device {
  * @blank: change the display's DPMS state.  Return 0 on success or error
  *	code (<0) on failure.
  *
+ * @alloc_simple_buffer: allocate a buffer with the specified @w, @h, and
+ *	@format.  @format will be a standard RGB format (i.e.,
+ *	adf_format_is_rgb(@format) == true).  Return 0 on success or error code
+ *	(<0) on failure.  On success, return the buffer, offset, and pitch in
+ *	@dma_buf, @offset, and @pitch respectively.
+ * @describe_simple_post: provide driver-private data needed to post a single
+ *	buffer @buf.  Copy up to ADF_MAX_CUSTOM_DATA_SIZE bytes into @data
+ *	(allocated by ADF) and return the number of bytes in @size.  Return 0 on
+ *	success or error code (<0) on failure.
+ *
  * @modeset: change the interface's mode.  @mode is not necessarily part of the
  *	modelist passed to adf_hotplug_notify_connected(); the driver may
  *	accept or reject custom modes at its discretion.  Return 0 on success or
@@ -318,6 +328,14 @@ struct adf_interface_ops {
 	int (*blank)(struct adf_interface *intf, u8 state);
 
 	/* optional */
+	int (*alloc_simple_buffer)(struct adf_interface *intf,
+			u16 w, u16 h, u32 format,
+			struct dma_buf **dma_buf, u32 *offset, u32 *pitch);
+	/* optional */
+	int (*describe_simple_post)(struct adf_interface *intf,
+			struct adf_buffer *fb, void *data, size_t *size);
+
+	/* optional */
 	int (*modeset)(struct adf_interface *intf,
 			struct drm_mode_modeinfo *mode);
 
diff --git a/include/video/adf_client.h b/include/video/adf_client.h
index 1e471a48998..983f2b6a589 100644
--- a/include/video/adf_client.h
+++ b/include/video/adf_client.h
@@ -28,6 +28,10 @@ int adf_interface_set_mode(struct adf_interface *intf,
 		struct drm_mode_modeinfo *mode);
 int adf_interface_get_screen_size(struct adf_interface *intf, u16 *width,
 		u16 *height);
+int adf_interface_simple_buffer_alloc(struct adf_interface *intf, u16 w, u16 h,
+		u32 format, struct dma_buf **dma_buf, u32 *offset, u32 *pitch);
+struct sync_fence *adf_interface_simple_post(struct adf_interface *intf,
+		struct adf_buffer *buf);
 
 bool adf_overlay_engine_supports_format(struct adf_overlay_engine *eng,
 		u32 format);