media: mediatek: vcodec: Add a debugfs file to get different useful information

In oder to get each instance information according to test command, adding
one file node "vdec".

Can use echo command to set different string value as
'echo -picinfo > vdec'.

Signed-off-by: Yunfei Dong <yunfei.dong@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
[hverkuil: drop unwanted dbgfs_inst NULL ptr check in mtk_vcodec_dbgfs_remove]
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

Author: yunfei-mtk

drivers/media/platform/mediatek/vcodec/mtk_vcodec_dbgfs.c

@@ -10,6 +10,63 @@
 #include "mtk_vcodec_drv.h"
 #include "mtk_vcodec_util.h"
 
+static ssize_t mtk_vdec_dbgfs_write(struct file *filp, const char __user *ubuf,
+				    size_t count, loff_t *ppos)
+{
+	struct mtk_vcodec_dev *vcodec_dev = filp->private_data;
+	struct mtk_vcodec_dbgfs *dbgfs = &vcodec_dev->dbgfs;
+
+	mutex_lock(&dbgfs->dbgfs_lock);
+	dbgfs->buf_size = simple_write_to_buffer(dbgfs->dbgfs_buf, sizeof(dbgfs->dbgfs_buf),
+						 ppos, ubuf, count);
+	mutex_unlock(&dbgfs->dbgfs_lock);
+	if (dbgfs->buf_size > 0)
+		return count;
+
+	return dbgfs->buf_size;
+}
+
+static const struct file_operations vdec_fops = {
+	.open = simple_open,
+	.write = mtk_vdec_dbgfs_write,
+};
+
+void mtk_vcodec_dbgfs_create(struct mtk_vcodec_ctx *ctx)
+{
+	struct mtk_vcodec_dbgfs_inst *dbgfs_inst;
+	struct mtk_vcodec_dev *vcodec_dev = ctx->dev;
+
+	dbgfs_inst = kzalloc(sizeof(*dbgfs_inst), GFP_KERNEL);
+	if (!dbgfs_inst)
+		return;
+
+	list_add_tail(&dbgfs_inst->node, &vcodec_dev->dbgfs.dbgfs_head);
+
+	vcodec_dev->dbgfs.inst_count++;
+
+	dbgfs_inst->inst_id = ctx->id;
+	dbgfs_inst->vcodec_ctx = ctx;
+}
+EXPORT_SYMBOL_GPL(mtk_vcodec_dbgfs_create);
+
+void mtk_vcodec_dbgfs_remove(struct mtk_vcodec_dev *vcodec_dev, int ctx_id)
+{
+	struct mtk_vcodec_dbgfs_inst *dbgfs_inst;
+
+	list_for_each_entry(dbgfs_inst, &vcodec_dev->dbgfs.dbgfs_head, node) {
+		if (dbgfs_inst->inst_id == ctx_id) {
+			vcodec_dev->dbgfs.inst_count--;
+			break;
+		}
+	}
+
+	if (dbgfs_inst) {
+		list_del(&dbgfs_inst->node);
+		kfree(dbgfs_inst);
+	}
+}
+EXPORT_SYMBOL_GPL(mtk_vcodec_dbgfs_remove);
+
 void mtk_vcodec_dbgfs_init(struct mtk_vcodec_dev *vcodec_dev)
 {
 	struct dentry *vcodec_root;
@@ -22,6 +79,12 @@ void mtk_vcodec_dbgfs_init(struct mtk_vcodec_dev *vcodec_dev)
 	vcodec_root = vcodec_dev->dbgfs.vcodec_root;
 	debugfs_create_x32("mtk_v4l2_dbg_level", 0644, vcodec_root, &mtk_v4l2_dbg_level);
 	debugfs_create_x32("mtk_vcodec_dbg", 0644, vcodec_root, &mtk_vcodec_dbg);
+
+	vcodec_dev->dbgfs.inst_count = 0;
+
+	INIT_LIST_HEAD(&vcodec_dev->dbgfs.dbgfs_head);
+	debugfs_create_file("vdec", 0200, vcodec_root, vcodec_dev, &vdec_fops);
+	mutex_init(&vcodec_dev->dbgfs.dbgfs_lock);
 }
 EXPORT_SYMBOL_GPL(mtk_vcodec_dbgfs_init);
 

drivers/media/platform/mediatek/vcodec/mtk_vcodec_dbgfs.h

@@ -8,19 +8,52 @@
 #define __MTK_VCODEC_DBGFS_H__
 
 struct mtk_vcodec_dev;
+struct mtk_vcodec_ctx;
+
+/**
+ * struct mtk_vcodec_dbgfs_inst  - debugfs information for each inst
+ * @node:       list node for each inst
+ * @vcodec_ctx: struct mtk_vcodec_ctx
+ * @inst_id:    index of the context that the same with ctx->id
+ */
+struct mtk_vcodec_dbgfs_inst {
+	struct list_head node;
+	struct mtk_vcodec_ctx *vcodec_ctx;
+	int inst_id;
+};
 
 /**
  * struct mtk_vcodec_dbgfs  - dbgfs information
+ * @dbgfs_head:  list head used to link each instance
  * @vcodec_root: vcodec dbgfs entry
+ * @dbgfs_lock:  dbgfs lock used to protect dbgfs_buf
+ * @dbgfs_buf:   dbgfs buf used to store dbgfs cmd
+ * @buf_size:    buffer size of dbgfs
+ * @inst_count:  the count of total instance
  */
 struct mtk_vcodec_dbgfs {
+	struct list_head dbgfs_head;
 	struct dentry *vcodec_root;
+	struct mutex dbgfs_lock;
+	char dbgfs_buf[1024];
+	int buf_size;
+	int inst_count;
 };
 
 #if defined(CONFIG_DEBUG_FS)
+void mtk_vcodec_dbgfs_create(struct mtk_vcodec_ctx *ctx);
+void mtk_vcodec_dbgfs_remove(struct mtk_vcodec_dev *vcodec_dev, int ctx_id);
 void mtk_vcodec_dbgfs_init(struct mtk_vcodec_dev *vcodec_dev);
 void mtk_vcodec_dbgfs_deinit(struct mtk_vcodec_dev *vcodec_dev);
 #else
+static inline void mtk_vcodec_dbgfs_create(struct mtk_vcodec_ctx *ctx)
+{
+}
+
+static inline void mtk_vcodec_dbgfs_remove(struct mtk_vcodec_dev *vcodec_dev, int ctx_id)
+{
+}
+
 static inline void mtk_vcodec_dbgfs_init(struct mtk_vcodec_dev *vcodec_dev)
 {
 }

drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec_drv.c

@@ -215,6 +215,7 @@ static int fops_vcodec_open(struct file *file)
 	ctx->dev->vdec_pdata->init_vdec_params(ctx);
 
 	list_add(&ctx->list, &dev->ctx_list);
+	mtk_vcodec_dbgfs_create(ctx);
 
 	mutex_unlock(&dev->dev_mutex);
 	mtk_v4l2_debug(0, "%s decoder [%d]", dev_name(&dev->plat_dev->dev),
@@ -256,6 +257,7 @@ static int fops_vcodec_release(struct file *file)
 	v4l2_fh_exit(&ctx->fh);
 	v4l2_ctrl_handler_free(&ctx->ctrl_hdl);
 
+	mtk_vcodec_dbgfs_remove(dev, ctx->id);
 	list_del_init(&ctx->list);
 	kfree(ctx);
 	mutex_unlock(&dev->dev_mutex);