[PATCH] dvb: flexcop: fix USB transfer handling

- driver receives many null TS packets (pid=0x1fff). They occupy the
limited USB bandwidth and this leads to loss of video packets. Enabling the
null packet filter fixes this.

- packets that flexcop sends to USB have a 2 byte header that has to be
removed.

- sometimes a TS packet is split between different urbs. These parts have
to be combined in a temporary buffer.

Signed-off-by: Vadim Catana <[e-mail]>
Signed-off-by: Patrick Boettcher <[e-mail]>
Signed-off-by: Johannes Stezenbach <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

drivers/media/dvb/b2c2/flexcop-hw-filter.c

···
 	} else if (fc->feedcount == onoff && !onoff) {
 		if (!fc->pid_filtering) {
 			deb_ts("disabling full TS transfer\n");
-			flexcop_pid_group_filter(fc, 0x1fe0,0);
+			flexcop_pid_group_filter(fc, 0, 0x1fe0);
 			flexcop_pid_group_filter_ctrl(fc,0);
 		}
 
···
 		flexcop_pid_group_filter(fc, 0,0);
 		flexcop_pid_group_filter_ctrl(fc,1);
 	} else if (fc->pid_filtering && fc->feedcount <= max_pid_filter) {
-		flexcop_pid_group_filter(fc, 0x1fe0,0);
+		flexcop_pid_group_filter(fc, 0,0x1fe0);
 		flexcop_pid_group_filter_ctrl(fc,0);
 	}
 
···
 	for (i = 0; i < 6 + 32*fc->has_32_hw_pid_filter; i++)
 		flexcop_pid_control(fc,i,0x1fff,0);
 
-	flexcop_pid_group_filter(fc, 0x1fe0,0);
+	flexcop_pid_group_filter(fc, 0, 0x1fe0);
+	flexcop_pid_group_filter_ctrl(fc,0);
 
 	v = fc->read_ibi_reg(fc,pid_filter_308);
 	v.pid_filter_308.EMM_filter_4 = 1;
 	v.pid_filter_308.EMM_filter_6 = 0;
 	fc->write_ibi_reg(fc,pid_filter_308,v);
+
+	flexcop_null_filter_ctrl(fc, 1);
 }

drivers/media/dvb/b2c2/flexcop-usb.c

···
 		return flexcop_usb_i2c_req(fc->bus_specific,B2C2_USB_I2C_REQUEST,USB_FUNC_I2C_WRITE,port,chipaddr,addr,buf,len);
 }
 
+static void flexcop_usb_process_frame(struct flexcop_usb *fc_usb, u8 *buffer, int buffer_length)
+{
+	u8 *b;
+	int l;
+
+	deb_ts("tmp_buffer_length=%d, buffer_length=%d\n", fc_usb->tmp_buffer_length, buffer_length);
+
+	if (fc_usb->tmp_buffer_length > 0) {
+		memcpy(fc_usb->tmp_buffer+fc_usb->tmp_buffer_length, buffer, buffer_length);
+		fc_usb->tmp_buffer_length += buffer_length;
+		b = fc_usb->tmp_buffer;
+		l = fc_usb->tmp_buffer_length;
+	} else {
+		b=buffer;
+		l=buffer_length;
+	}
+
+	while (l >= 190) {
+		if (*b == 0xff)
+			switch (*(b+1) & 0x03) {
+				case 0x01: /* media packet */
+					if ( *(b+2) == 0x47 )
+						flexcop_pass_dmx_packets(fc_usb->fc_dev, b+2, 1);
+					else
+						deb_ts("not ts packet %02x %02x %02x %02x \n", *(b+2), *(b+3), *(b+4), *(b+5) );
+
+					b += 190;
+					l -= 190;
+				break;
+				default:
+					deb_ts("wrong packet type\n");
+					l = 0;
+				break;
+			}
+		else {
+			deb_ts("wrong header\n");
+			l = 0;
+		}
+	}
+
+	if (l>0)
+		memcpy(fc_usb->tmp_buffer, b, l);
+	fc_usb->tmp_buffer_length = l;
+}
+
 static void flexcop_usb_urb_complete(struct urb *urb, struct pt_regs *ptregs)
 {
 	struct flexcop_usb *fc_usb = urb->context;
···
 			if (urb->iso_frame_desc[i].actual_length > 0) {
 				deb_ts("passed %d bytes to the demux\n",urb->iso_frame_desc[i].actual_length);
 
-				flexcop_pass_dmx_data(fc_usb->fc_dev,
+				flexcop_usb_process_frame(fc_usb,
 					urb->transfer_buffer + urb->iso_frame_desc[i].offset,
 					urb->iso_frame_desc[i].actual_length);
 		}

drivers/media/dvb/b2c2/flexcop-usb.h

···
 	struct urb *iso_urb[B2C2_USB_NUM_ISO_URB];
 
 	struct flexcop_device *fc_dev;
+
+	u8 tmp_buffer[1023+190];
+	int tmp_buffer_length;
 };
 
 #if 0