diff options
| -rw-r--r-- | drivers/media/usb/em28xx/em28xx-video.c | 74 |
1 files changed, 73 insertions, 1 deletions
diff --git a/drivers/media/usb/em28xx/em28xx-video.c b/drivers/media/usb/em28xx/em28xx-video.c index b1817231f50c..ef1959bbd23f 100644 --- a/drivers/media/usb/em28xx/em28xx-video.c +++ b/drivers/media/usb/em28xx/em28xx-video.c @@ -76,6 +76,16 @@ MODULE_DESCRIPTION(DRIVER_DESC); MODULE_LICENSE("GPL"); MODULE_VERSION(EM28XX_VERSION); + +#define EM25XX_FRMDATAHDR_BYTE1 0x02 +#define EM25XX_FRMDATAHDR_BYTE2_STILL_IMAGE 0x20 +#define EM25XX_FRMDATAHDR_BYTE2_FRAME_END 0x02 +#define EM25XX_FRMDATAHDR_BYTE2_FRAME_ID 0x01 +#define EM25XX_FRMDATAHDR_BYTE2_MASK (EM25XX_FRMDATAHDR_BYTE2_STILL_IMAGE | \ + EM25XX_FRMDATAHDR_BYTE2_FRAME_END | \ + EM25XX_FRMDATAHDR_BYTE2_FRAME_ID) + + static unsigned int video_nr[] = {[0 ... (EM28XX_MAXBOARDS - 1)] = -1U }; static unsigned int vbi_nr[] = {[0 ... (EM28XX_MAXBOARDS - 1)] = -1U }; static unsigned int radio_nr[] = {[0 ... (EM28XX_MAXBOARDS - 1)] = -1U }; @@ -408,6 +418,62 @@ static inline void process_frame_data_em28xx(struct em28xx *dev, em28xx_copy_video(dev, buf, data_pkt, data_len); } +/* + * Process data packet according to the em25xx/em276x/7x/8x frame data format + */ +static inline void process_frame_data_em25xx(struct em28xx *dev, + unsigned char *data_pkt, + unsigned int data_len) +{ + struct em28xx_buffer *buf = dev->usb_ctl.vid_buf; + struct em28xx_dmaqueue *dmaq = &dev->vidq; + bool frame_end = 0; + + /* Check for header */ + /* NOTE: at least with bulk transfers, only the first packet + * has a header and has always set the FRAME_END bit */ + if (data_len >= 2) { /* em25xx header is only 2 bytes long */ + if ((data_pkt[0] == EM25XX_FRMDATAHDR_BYTE1) && + ((data_pkt[1] & ~EM25XX_FRMDATAHDR_BYTE2_MASK) == 0x00)) { + dev->top_field = !(data_pkt[1] & + EM25XX_FRMDATAHDR_BYTE2_FRAME_ID); + frame_end = data_pkt[1] & + EM25XX_FRMDATAHDR_BYTE2_FRAME_END; + data_pkt += 2; + data_len -= 2; + } + + /* Finish field and prepare next (BULK only) */ + if (dev->analog_xfer_bulk && frame_end) { + buf = finish_field_prepare_next(dev, buf, dmaq); + dev->usb_ctl.vid_buf = buf; + } + /* NOTE: in ISOC mode when a new frame starts and buf==NULL, + * we COULD already prepare a buffer here to avoid skipping the + * first frame. + */ + } + + /* Copy data */ + if (buf != NULL && data_len > 0) + em28xx_copy_video(dev, buf, data_pkt, data_len); + + /* Finish frame (ISOC only) => avoids lag of 1 frame */ + if (!dev->analog_xfer_bulk && frame_end) { + buf = finish_field_prepare_next(dev, buf, dmaq); + dev->usb_ctl.vid_buf = buf; + } + + /* NOTE: Tested with USB bulk transfers only ! + * The wording in the datasheet suggests that isoc might work different. + * The current code assumes that with isoc transfers each packet has a + * header like with the other em28xx devices. + */ + /* NOTE: Support for interlaced mode is pure theory. It has not been + * tested and it is unknown if these devices actually support it. */ + /* NOTE: No VBI support yet (these chips likely do not support VBI). */ +} + /* Processes and copies the URB data content (video and VBI data) */ static inline int em28xx_urb_data_copy(struct em28xx *dev, struct urb *urb) { @@ -460,7 +526,13 @@ static inline int em28xx_urb_data_copy(struct em28xx *dev, struct urb *urb) continue; } - process_frame_data_em28xx(dev, usb_data_pkt, usb_data_len); + if (dev->is_em25xx) + process_frame_data_em25xx(dev, + usb_data_pkt, usb_data_len); + else + process_frame_data_em28xx(dev, + usb_data_pkt, usb_data_len); + } return 1; } |