media: aspeed: add comments and macro

Add comments to describe video-stat and 'struct aspeed_video'.
Add macro, ASPEED_VIDEO_V4L2_MIN_BUF_REQ, to describe the buffers
needed.

Signed-off-by: Jammy Huang <jammy_huang@aspeedtech.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
[hverkuil: drop docbook tags, not needed]

diff --git a/drivers/media/platform/aspeed-video.c b/drivers/media/platform/aspeed-video.c
index 51fb184..06ab9e9 100644 (file)
--- a/drivers/media/platform/aspeed-video.c
+++ b/drivers/media/platform/aspeed-video.c
@@ -34,6 +34,8 @@
 #include <media/videobuf2-dma-contig.h>
 #include <linux/videodev2.h>
 
+#define ASPEED_VIDEO_V4L2_MIN_BUF_REQ 3
+
 #define DEVICE_NAME                    "aspeed-video"
 
 #define ASPEED_VIDEO_JPEG_NUM_QUALITIES        12
@@ -181,6 +183,15 @@
 #define VE_MEM_RESTRICT_START          0x310
 #define VE_MEM_RESTRICT_END            0x314
 
+/*
+ * VIDEO_MODE_DETECT_DONE:     a flag raised if signal lock
+ * VIDEO_RES_CHANGE:           a flag raised if res_change work on-going
+ * VIDEO_RES_DETECT:           a flag raised if res. detection on-going
+ * VIDEO_STREAMING:            a flag raised if user requires stream-on
+ * VIDEO_FRAME_INPRG:          a flag raised if hw working on a frame
+ * VIDEO_STOPPED:              a flag raised if device release
+ * VIDEO_CLOCKS_ON:            a flag raised if clk is on
+ */
 enum {
        VIDEO_MODE_DETECT_DONE,
        VIDEO_RES_CHANGE,
@@ -213,6 +224,25 @@ struct aspeed_video_perf {
 #define to_aspeed_video_buffer(x) \
        container_of((x), struct aspeed_video_buffer, vb)
 
+/*
+ * struct aspeed_video - driver data
+ *
+ * res_work:           holds the delayed_work for res-detection if unlock
+ * buffers:            holds the list of buffer queued from user
+ * flags:              holds the state of video
+ * sequence:           holds the last number of frame completed
+ * max_compressed_size:        holds max compressed stream's size
+ * srcs:               holds the buffer information for srcs
+ * jpeg:               holds the buffer information for jpeg header
+ * yuv420:             a flag raised if JPEG subsampling is 420
+ * frame_rate:         holds the frame_rate
+ * jpeg_quality:       holds jpeq's quality (0~11)
+ * frame_bottom:       end position of video data in vertical direction
+ * frame_left:         start position of video data in horizontal direction
+ * frame_right:                end position of video data in horizontal direction
+ * frame_top:          start position of video data in vertical direction
+ * perf:               holds the statistics primary for debugfs
+ */
 struct aspeed_video {
        void __iomem *base;
        struct clk *eclk;
@@ -1212,7 +1242,7 @@ static int aspeed_video_get_parm(struct file *file, void *fh,
        struct aspeed_video *video = video_drvdata(file);
 
        a->parm.capture.capability = V4L2_CAP_TIMEPERFRAME;
-       a->parm.capture.readbuffers = 3;
+       a->parm.capture.readbuffers = ASPEED_VIDEO_V4L2_MIN_BUF_REQ;
        a->parm.capture.timeperframe.numerator = 1;
        if (!video->frame_rate)
                a->parm.capture.timeperframe.denominator = MAX_FRAME_RATE;
@@ -1229,7 +1259,7 @@ static int aspeed_video_set_parm(struct file *file, void *fh,
        struct aspeed_video *video = video_drvdata(file);
 
        a->parm.capture.capability = V4L2_CAP_TIMEPERFRAME;
-       a->parm.capture.readbuffers = 3;
+       a->parm.capture.readbuffers = ASPEED_VIDEO_V4L2_MIN_BUF_REQ;
 
        if (a->parm.capture.timeperframe.numerator)
                frame_rate = a->parm.capture.timeperframe.denominator /
@@ -1781,7 +1811,7 @@ static int aspeed_video_setup_video(struct aspeed_video *video)
        vbq->drv_priv = video;
        vbq->buf_struct_size = sizeof(struct aspeed_video_buffer);
        vbq->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
-       vbq->min_buffers_needed = 3;
+       vbq->min_buffers_needed = ASPEED_VIDEO_V4L2_MIN_BUF_REQ;
 
        rc = vb2_queue_init(vbq);
        if (rc) {