On Sun, 15 Mar 2009 10:42:41 -0700 (PDT), Trent Piepho wrote: > On Sun, 15 Mar 2009, Jean Delvare wrote: > > On Sun, 15 Mar 2009 13:44:01 +0100, Hans Verkuil wrote: > > This is the typical multifunction device problem. It isn't specifically > > related to I2C, the exact same problem happens for other devices, for > > example a PCI south bridge including hardware monitoring and SMBus, or > > a Super-I/O chip including hardware monitoring, parallel port, > > infrared, watchdog, etc. Linux currently only allows one driver to bind > > to a given device, so it becomes very difficult to make per-function > > drivers for such devices. > > > > For very specific devices, it isn't necessarily a big problem. You can > > simply make an all-in-one driver for that specific device. The real > > problem is when the device in question is fully compatible with other > > devices which only implement functionality A _and_ fully compatible with > > other devices which only implement functionality B. You don't really > > want to support functions A and B in the same driver if most devices > > out there have either function but not both. > > You can also split the "device" into multiple devices. Most SoCs have one > register block where all kinds of devices, from i2c controllers to network > adapters, exist. This is shown to linux as many devices, rather than one > massive multifunction device.
It really depends on the device type. You can't split an I2C or PCI device that way. -- Jean Delvare -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
