Set appropriate bulk/ISOC transfer multiplier on capture start.
This sets ISOC transfer to 940 bytes (188 * 5)
This sets bulk transfer to 48128 bytes (188 * 256)

The above values are maximum allowed according to Empia.

Signed-off-by: Brad Love <b...@nextdimension.cc>
---
 drivers/media/usb/em28xx/em28xx-core.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/media/usb/em28xx/em28xx-core.c 
b/drivers/media/usb/em28xx/em28xx-core.c
index ef38e56..67ed6a3 100644
--- a/drivers/media/usb/em28xx/em28xx-core.c
+++ b/drivers/media/usb/em28xx/em28xx-core.c
@@ -638,6 +638,18 @@ int em28xx_capture_start(struct em28xx *dev, int start)
            dev->chip_id == CHIP_ID_EM28174 ||
            dev->chip_id == CHIP_ID_EM28178) {
                /* The Transport Stream Enable Register moved in em2874 */
+               if (dev->dvb_xfer_bulk) {
+                       /* Max Tx Size = 188 * 256 = 48128 - LCM(188,512) * 2 */
+                       em28xx_write_reg(dev, (dev->ts == PRIMARY_TS) ?
+                                       EM2874_R5D_TS1_PKT_SIZE :
+                                       EM2874_R5E_TS2_PKT_SIZE,
+                                       0xFF);
+               } else {
+                       /* TS2 Maximum Transfer Size = 188 * 5 */
+                       em28xx_write_reg(dev, (dev->ts == PRIMARY_TS) ?
+                                       EM2874_R5D_TS1_PKT_SIZE :
+                                       EM2874_R5E_TS2_PKT_SIZE, 0x05);
+               }
                if (dev->ts == PRIMARY_TS)
                        rc = em28xx_write_reg_bits(dev,
                                EM2874_R5F_TS_ENABLE,
-- 
2.7.4

Reply via email to