V4L/DVB (7786): cx18: new driver for the Conexant CX23418 MPEG encoder chip

Many thanks to Steve Toth from Hauppauge and Nattu Dakshinamurthy from
Conexant for their support. I am in particular thankful to Hauppauge
since without their help this driver would not exist. It should also
be noted that Steve did the work to get the DVB part up and running.
Thank you!

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Steven Toth <stoth@hauppauge.com>
Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: G. Andrew Walls <awalls@radix.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

Documentation/video4linux/cx18.txt

@@ -0,0 +1,34 @@
+Some notes regarding the cx18 driver for the Conexant CX23418 MPEG
+encoder chip:
+
+1) The only hardware currently supported is the Hauppauge HVR-1600.
+
+2) Some people have problems getting the i2c bus to work. Cause unknown.
+   The symptom is that the eeprom cannot be read and the card is
+   unusable.
+
+3) The audio from the analog tuner is mono only. Probably caused by
+   incorrect audio register information in the datasheet. We are
+   waiting for updated information from Conexant.
+
+4) VBI (raw or sliced) has not yet been implemented.
+
+5) MPEG indexing is not yet implemented.
+
+6) The driver is still a bit rough around the edges, this should
+   improve over time.
+
+
+Firmware:
+
+The firmware needs to be extracted from the Windows Hauppauge HVR-1600
+driver, available here:
+
+http://hauppauge.lightpath.net/software/install_cd/hauppauge_cd_3.4d1.zip
+
+Unzip, then copy the following files to the firmware directory
+and rename them as follows:
+
+Drivers/Driver18/hcw18apu.rom -> v4l-cx23418-apu.fw
+Drivers/Driver18/hcw18enc.rom -> v4l-cx23418-cpu.fw
+Drivers/Driver18/hcw18mlC.rom -> v4l-cx23418-dig.fw