[RFCv1] DVB-USB improvements

[Antti Palosaari <crope@iki.fi>]

Factors behind the changes are mostly coming from the fact current 
struct dvb_usb_device_properties contains so many static configuration 
options. You cannot change single dvb_usb_device_properties easily 
(safely) at runtime since it is usually driver global struct and thus 
shared between all the DVB USB driver instances. That fits just fine for 
the traditional devices where all configuration is same for the devices 
having single USB ID. Nowadays we have more and more devices that are 
based of chipset vendor reference designs - even using just single USB 
ID chipset vendor have given for that chipset. These reference designs 
still varies much about used chips and configurations. Configuring 
different base chips, USB-bridge, demod, tuner, and also peripheral 
properties like dual tuners, remotes and CI is needed to do runtime 
because of single USB ID is used for that all.

My personal innovator behind all these is problems I met when developing 
AF9015 and AF9035 drivers. Also RTL2831U and RTL2832U are kinda similar 
and have given some more motivation.

Here is small list what I am planning to do. It is surely so much work 
that everything is not possible, but lets try to select most important 
and easiest as a higher priority.


resume / suspend support
-------------------
* very important feature
* crashes currently when DVB USB tries to download firmware when 
resuming from suspend

read_config1
-------------------
* new callback to do initial tweaks
* very first callback
* is that really needed?

read_mac_address => read_config2
-------------------
* rename it read_config2 or read_config if read_config1 is not 
implemented at all
* rename old callback and extend it usage as a more general
* only 8 devices use currently
* when returned mac != 0 => print mac address as earlier, otherwise work 
as a general callback

new callback init()
-------------------
* called after tuner attach to initialize rest of device
* good place to do some general settings
   - configure endpoints
   - configure remote controller
   - configure + attach CI

change DVB-USB to dynamic debug
-------------------
* use Kernel new dynamic debugs instead of own proprietary system

download_firmware
-------------------
* struct usb_device => struct dvb_usb_device
* we need access for the DVB USB driver state in every callback

identify_state
-------------------
* struct usb_device => struct dvb_usb_device
* we need access for the DVB USB driver state in every callback

attach all given adapter frontends as once
-------------------
* for the MFE devices attach all frontends as once
* deregister all frontends if error returned
* small effect only for MFE

attach all given adapter tuners as once
-------------------
* deregister all frontends if error returned
* small effect only for MFE

make remote dynamically configurable
-------------------
* default keytable mapped same level with USB-ID & device name etc.
* there is generally 3 things that could be mapped to USB ID
   - USB IDs (cold + warm)
   - device name
   - remote controller keytable
   - all the others could be resolved & configured dynamically
* it is not only keytable but whole remote should be changed dynamically 
configurable

make stream dynamically configurable
-------------------
* we need change stream parameters in certain situations
   - there is multiple endpoints but shared MFE
   - need to set params according to stream bandwidth (USB1.1, DVB-T, 
DVB-C2 in same device)
   - leave old static configrations as those are but add callbacks to 
get new values at runtime

dynamically growing device list in dvb_usb_device_properties
-------------------
* currently number of devices are limited statically
* there is devices having ~50 or more IDs which means multiple 
dvb_usb_device_properties are needed

dynamic USB ID support
-------------------
* currently not supported by DVB USB

analog support for the DVB USB
-------------------
* currently not supported by DVB USB
* I have no experience
* em28xx can be converted?



-- 
http://palosaari.fi/