Commit 4078d625 authored by Frank Schaefer's avatar Frank Schaefer Committed by Mauro Carvalho Chehab

[media] em28xx: move caching of pointer to vmalloc memory in videobuf to struct em28xx_buffer

In the current code em28xx_urb_data_copy() caches the pointer to the vmalloc
memory in videobuf locally.
The alternative would be to call videobuf_to_vmalloc() for each processed USB
data packet (isoc USB transfers => 64 times per URB) in the em28xx_copy_*()
functions.
With the next commits, the data processing code will be split into functions
for serveral reasons:
- em28xx_urb_data_copy() is generally way to long, making it less readable
- there is code duplication between VBI and video data processing
- support for em25xx data processing (uses a different header and frame
  end signaling mechanism) will be added
This would require extensive usage of pointer-pointers, which usually makes the
code less readable and prone to bugs.
The better solution is to cache the pointer in struct em28xx_buffer.
This also improves consistency, because we already track the buffer fill count there.
Signed-off-by: default avatarFrank Schäfer <fschaefer.oss@googlemail.com>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@redhat.com>
parent a4837015
...@@ -173,11 +173,12 @@ static inline void finish_buffer(struct em28xx *dev, ...@@ -173,11 +173,12 @@ static inline void finish_buffer(struct em28xx *dev,
static void em28xx_copy_video(struct em28xx *dev, static void em28xx_copy_video(struct em28xx *dev,
struct em28xx_buffer *buf, struct em28xx_buffer *buf,
unsigned char *p, unsigned char *p,
unsigned char *outp, unsigned long len) unsigned long len)
{ {
void *fieldstart, *startwrite, *startread; void *fieldstart, *startwrite, *startread;
int linesdone, currlinedone, offset, lencopy, remain; int linesdone, currlinedone, offset, lencopy, remain;
int bytesperline = dev->width << 1; int bytesperline = dev->width << 1;
unsigned char *outp = buf->vb_buf;
if (buf->pos + len > buf->vb.size) if (buf->pos + len > buf->vb.size)
len = buf->vb.size - buf->pos; len = buf->vb.size - buf->pos;
...@@ -249,11 +250,12 @@ static void em28xx_copy_video(struct em28xx *dev, ...@@ -249,11 +250,12 @@ static void em28xx_copy_video(struct em28xx *dev,
static void em28xx_copy_vbi(struct em28xx *dev, static void em28xx_copy_vbi(struct em28xx *dev,
struct em28xx_buffer *buf, struct em28xx_buffer *buf,
unsigned char *p, unsigned char *p,
unsigned char *outp, unsigned long len) unsigned long len)
{ {
void *startwrite, *startread; void *startwrite, *startread;
int offset; int offset;
int bytesperline; int bytesperline;
unsigned char *outp;
if (dev == NULL) { if (dev == NULL) {
em28xx_isocdbg("dev is null\n"); em28xx_isocdbg("dev is null\n");
...@@ -268,6 +270,7 @@ static void em28xx_copy_vbi(struct em28xx *dev, ...@@ -268,6 +270,7 @@ static void em28xx_copy_vbi(struct em28xx *dev,
em28xx_isocdbg("p is null\n"); em28xx_isocdbg("p is null\n");
return; return;
} }
outp = buf->vb_buf;
if (outp == NULL) { if (outp == NULL) {
em28xx_isocdbg("outp is null\n"); em28xx_isocdbg("outp is null\n");
return; return;
...@@ -350,6 +353,7 @@ static inline struct em28xx_buffer *get_next_buf(struct em28xx *dev, ...@@ -350,6 +353,7 @@ static inline struct em28xx_buffer *get_next_buf(struct em28xx *dev,
outp = videobuf_to_vmalloc(&buf->vb); outp = videobuf_to_vmalloc(&buf->vb);
memset(outp, 0, buf->vb.size); memset(outp, 0, buf->vb.size);
buf->pos = 0; buf->pos = 0;
buf->vb_buf = outp;
return buf; return buf;
} }
...@@ -362,7 +366,7 @@ static inline int em28xx_urb_data_copy(struct em28xx *dev, struct urb *urb) ...@@ -362,7 +366,7 @@ static inline int em28xx_urb_data_copy(struct em28xx *dev, struct urb *urb)
struct em28xx_dmaqueue *vbi_dma_q = &dev->vbiq; struct em28xx_dmaqueue *vbi_dma_q = &dev->vbiq;
int xfer_bulk, num_packets, i, rc = 1; int xfer_bulk, num_packets, i, rc = 1;
unsigned int actual_length, len = 0; unsigned int actual_length, len = 0;
unsigned char *p, *outp = NULL, *vbioutp = NULL; unsigned char *p;
if (!dev) if (!dev)
return 0; return 0;
...@@ -376,12 +380,7 @@ static inline int em28xx_urb_data_copy(struct em28xx *dev, struct urb *urb) ...@@ -376,12 +380,7 @@ static inline int em28xx_urb_data_copy(struct em28xx *dev, struct urb *urb)
xfer_bulk = usb_pipebulk(urb->pipe); xfer_bulk = usb_pipebulk(urb->pipe);
buf = dev->usb_ctl.vid_buf; buf = dev->usb_ctl.vid_buf;
if (buf != NULL)
outp = videobuf_to_vmalloc(&buf->vb);
vbi_buf = dev->usb_ctl.vbi_buf; vbi_buf = dev->usb_ctl.vbi_buf;
if (vbi_buf != NULL)
vbioutp = videobuf_to_vmalloc(&vbi_buf->vb);
if (xfer_bulk) /* bulk */ if (xfer_bulk) /* bulk */
num_packets = 1; num_packets = 1;
...@@ -455,11 +454,6 @@ static inline int em28xx_urb_data_copy(struct em28xx *dev, struct urb *urb) ...@@ -455,11 +454,6 @@ static inline int em28xx_urb_data_copy(struct em28xx *dev, struct urb *urb)
finish_buffer(dev, vbi_buf); finish_buffer(dev, vbi_buf);
vbi_buf = get_next_buf(dev, vbi_dma_q); vbi_buf = get_next_buf(dev, vbi_dma_q);
dev->usb_ctl.vbi_buf = vbi_buf; dev->usb_ctl.vbi_buf = vbi_buf;
if (vbi_buf == NULL)
vbioutp = NULL;
else
vbioutp =
videobuf_to_vmalloc(&vbi_buf->vb);
} }
if (vbi_buf != NULL) { if (vbi_buf != NULL) {
vbi_buf->top_field = dev->top_field; vbi_buf->top_field = dev->top_field;
...@@ -474,8 +468,7 @@ static inline int em28xx_urb_data_copy(struct em28xx *dev, struct urb *urb) ...@@ -474,8 +468,7 @@ static inline int em28xx_urb_data_copy(struct em28xx *dev, struct urb *urb)
/* Copy VBI data */ /* Copy VBI data */
if (vbi_buf != NULL) if (vbi_buf != NULL)
em28xx_copy_vbi(dev, vbi_buf, p, vbioutp, em28xx_copy_vbi(dev, vbi_buf, p, vbi_data_len);
vbi_data_len);
dev->vbi_read += vbi_data_len; dev->vbi_read += vbi_data_len;
if (vbi_data_len < len) { if (vbi_data_len < len) {
...@@ -493,10 +486,6 @@ static inline int em28xx_urb_data_copy(struct em28xx *dev, struct urb *urb) ...@@ -493,10 +486,6 @@ static inline int em28xx_urb_data_copy(struct em28xx *dev, struct urb *urb)
finish_buffer(dev, buf); finish_buffer(dev, buf);
buf = get_next_buf(dev, dma_q); buf = get_next_buf(dev, dma_q);
dev->usb_ctl.vid_buf = buf; dev->usb_ctl.vid_buf = buf;
if (buf == NULL)
outp = NULL;
else
outp = videobuf_to_vmalloc(&buf->vb);
} }
if (buf != NULL) { if (buf != NULL) {
buf->top_field = dev->top_field; buf->top_field = dev->top_field;
...@@ -505,7 +494,7 @@ static inline int em28xx_urb_data_copy(struct em28xx *dev, struct urb *urb) ...@@ -505,7 +494,7 @@ static inline int em28xx_urb_data_copy(struct em28xx *dev, struct urb *urb)
} }
if (buf != NULL && dev->capture_type == 3 && len > 0) if (buf != NULL && dev->capture_type == 3 && len > 0)
em28xx_copy_video(dev, buf, p, outp, len); em28xx_copy_video(dev, buf, p, len);
} }
return rc; return rc;
} }
......
...@@ -258,6 +258,9 @@ struct em28xx_buffer { ...@@ -258,6 +258,9 @@ struct em28xx_buffer {
unsigned int pos; unsigned int pos;
/* NOTE; in interlaced mode, this value is reset to zero at /* NOTE; in interlaced mode, this value is reset to zero at
* the start of each new field (not frame !) */ * the start of each new field (not frame !) */
/* pointer to vmalloc memory address in vb */
char *vb_buf;
}; };
struct em28xx_dmaqueue { struct em28xx_dmaqueue {
......
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