diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/media/dvb-core/dvb_ca_en50221.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/drivers/media/dvb-core/dvb_ca_en50221.c b/drivers/media/dvb-core/dvb_ca_en50221.c index 8d65028c7a74..d38bf9bce480 100644 --- a/drivers/media/dvb-core/dvb_ca_en50221.c +++ b/drivers/media/dvb-core/dvb_ca_en50221.c @@ -785,6 +785,29 @@ static int dvb_ca_en50221_write_data(struct dvb_ca_private *ca, int slot, u8 * b goto exit; } + /* + * It may need some time for the CAM to settle down, or there might + * be a race condition between the CAM, writing HC and our last + * check for DA. This happens, if the CAM asserts DA, just after + * checking DA before we are setting HC. In this case it might be + * a bug in the CAM to keep the FR bit, the lower layer/HW + * communication requires a longer timeout or the CAM needs more + * time internally. But this happens in reality! + * We need to read the status from the HW again and do the same + * we did for the previous check for DA + */ + status = ca->pub->read_cam_control(ca->pub, slot, CTRLIF_STATUS); + if (status < 0) + goto exit; + + if (status & (STATUSREG_DA | STATUSREG_RE)) { + if (status & STATUSREG_DA) + dvb_ca_en50221_thread_wakeup(ca); + + status = -EAGAIN; + goto exit; + } + /* send the amount of data */ if ((status = ca->pub->write_cam_control(ca->pub, slot, CTRLIF_SIZE_HIGH, bytes_write >> 8)) != 0) goto exit; |