From e36802c6297adb0c560f3a6c1672546eb380c458 Mon Sep 17 00:00:00 2001
From: Maxime Jourdan <mjourdan@baylibre.com>
Date: Wed, 10 Oct 2018 17:22:27 +0200
Subject: [PATCH] meson: vdec: introduce controls and
 V4L2_CID_MIN_BUFFERS_FOR_CAPTURE

---
 drivers/media/platform/meson/vdec/Makefile     |  2 +-
 drivers/media/platform/meson/vdec/vdec.c       |  7 ++++
 drivers/media/platform/meson/vdec/vdec.h       |  2 ++
 drivers/media/platform/meson/vdec/vdec_ctrls.c | 45 ++++++++++++++++++++++++++
 drivers/media/platform/meson/vdec/vdec_ctrls.h |  8 +++++
 5 files changed, 63 insertions(+), 1 deletion(-)
 create mode 100644 drivers/media/platform/meson/vdec/vdec_ctrls.c
 create mode 100644 drivers/media/platform/meson/vdec/vdec_ctrls.h

diff --git a/drivers/media/platform/meson/vdec/Makefile b/drivers/media/platform/meson/vdec/Makefile
index 6bea129..eba8608 100644
--- a/drivers/media/platform/meson/vdec/Makefile
+++ b/drivers/media/platform/meson/vdec/Makefile
@@ -1,7 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0
 # Makefile for Amlogic meson video decoder driver
 
-meson-vdec-objs = esparser.o vdec.o vdec_helpers.o vdec_platform.o
+meson-vdec-objs = esparser.o vdec.o vdec_ctrls.o vdec_helpers.o vdec_platform.o
 meson-vdec-objs += vdec_1.o
 meson-vdec-objs += codec_mpeg12.o
 
diff --git a/drivers/media/platform/meson/vdec/vdec.c b/drivers/media/platform/meson/vdec/vdec.c
index d8db52c..1c5d3e9 100644
--- a/drivers/media/platform/meson/vdec/vdec.c
+++ b/drivers/media/platform/meson/vdec/vdec.c
@@ -21,6 +21,7 @@
 #include "vdec.h"
 #include "esparser.h"
 #include "vdec_helpers.h"
+#include "vdec_ctrls.h"
 
 struct dummy_buf {
 	struct vb2_v4l2_buffer vb;
@@ -290,6 +291,7 @@ static int vdec_start_streaming(struct vb2_queue *q, unsigned int count)
 	sess->keyframe_found = 0;
 	sess->last_offset = 0;
 	sess->wrap_count = 0;
+	sess->dpb_size = 0;
 	sess->pixelaspect.numerator = 1;
 	sess->pixelaspect.denominator = 1;
 	atomic_set(&sess->esparser_queued_bufs, 0);
@@ -812,6 +814,10 @@ static int vdec_open(struct file *file)
 		goto err_m2m_release;
 	}
 
+	ret = amvdec_init_ctrls(&sess->ctrl_handler);
+	if (ret)
+		goto err_m2m_release;
+
 	sess->pixfmt_cap = formats[0].pixfmts_cap[0];
 	sess->fmt_out = &formats[0];
 	sess->width = 1280;
@@ -827,6 +833,7 @@ static int vdec_open(struct file *file)
 	spin_lock_init(&sess->ts_spinlock);
 
 	v4l2_fh_init(&sess->fh, core->vdev_dec);
+	sess->fh.ctrl_handler = &sess->ctrl_handler;
 	v4l2_fh_add(&sess->fh);
 	sess->fh.m2m_ctx = sess->m2m_ctx;
 	file->private_data = &sess->fh;
diff --git a/drivers/media/platform/meson/vdec/vdec.h b/drivers/media/platform/meson/vdec/vdec.h
index 4e8c3f1..6be7de2 100644
--- a/drivers/media/platform/meson/vdec/vdec.h
+++ b/drivers/media/platform/meson/vdec/vdec.h
@@ -203,6 +203,7 @@ struct amvdec_session {
 	struct v4l2_fh fh;
 	struct v4l2_m2m_dev *m2m_dev;
 	struct v4l2_m2m_ctx *m2m_ctx;
+	struct v4l2_ctrl_handler ctrl_handler;
 	struct mutex lock;
 
 	const struct amvdec_format *fmt_out;
@@ -242,6 +243,7 @@ struct amvdec_session {
 	u64 last_irq_jiffies;
 	u32 last_offset;
 	u32 wrap_count;
+	u32 dpb_size;
 
 	void *priv;
 };
diff --git a/drivers/media/platform/meson/vdec/vdec_ctrls.c b/drivers/media/platform/meson/vdec/vdec_ctrls.c
new file mode 100644
index 0000000..cd6dd6d
--- /dev/null
+++ b/drivers/media/platform/meson/vdec/vdec_ctrls.c
@@ -0,0 +1,45 @@
+#include "vdec_ctrls.h"
+
+static int vdec_op_g_volatile_ctrl(struct v4l2_ctrl *ctrl)
+{
+	struct amvdec_session *sess =
+	      container_of(ctrl->handler, struct amvdec_session, ctrl_handler);
+
+	switch (ctrl->id) {
+	case V4L2_CID_MIN_BUFFERS_FOR_CAPTURE:
+		ctrl->val = sess->dpb_size;
+		break;
+	default:
+		return -EINVAL;
+	};
+
+	return 0;
+}
+
+static const struct v4l2_ctrl_ops vdec_ctrl_ops = {
+	.g_volatile_ctrl = vdec_op_g_volatile_ctrl,
+};
+
+int amvdec_init_ctrls(struct v4l2_ctrl_handler *ctrl_handler)
+{
+	int ret;
+	struct v4l2_ctrl *ctrl;
+
+	ret = v4l2_ctrl_handler_init(ctrl_handler, 1);
+	if (ret)
+		return ret;
+
+	ctrl = v4l2_ctrl_new_std(ctrl_handler, &vdec_ctrl_ops,
+		V4L2_CID_MIN_BUFFERS_FOR_CAPTURE, 1, 32, 1, 1);
+	if (ctrl)
+		ctrl->flags |= V4L2_CTRL_FLAG_VOLATILE;
+
+	ret = ctrl_handler->error;
+	if (ret) {
+		v4l2_ctrl_handler_free(ctrl_handler);
+		return ret;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(amvdec_init_ctrls);
diff --git a/drivers/media/platform/meson/vdec/vdec_ctrls.h b/drivers/media/platform/meson/vdec/vdec_ctrls.h
new file mode 100644
index 0000000..4bcc5e6
--- /dev/null
+++ b/drivers/media/platform/meson/vdec/vdec_ctrls.h
@@ -0,0 +1,8 @@
+#ifndef __MESON_VDEC_CTRLS_H_
+#define __MESON_VDEC_CTRLS_H_
+
+#include "vdec.h"
+
+int amvdec_init_ctrls(struct v4l2_ctrl_handler *ctrl_handler);
+
+#endif