On Wed, Mar 02, 2016 at 09:36:55AM -0800, Aaron Marburg wrote: > On Wed, 2 Mar 2016, Oliver Neukum wrote: > > > On Tue, 2016-03-01 at 09:54 -0800, amarburg@xxxxxxxxxxxxxxxxxx wrote: > >> From: Aaron Marburg <amarburg@xxxxxxxxxxxxxxxxxx> > >> > >> The USOPTL4-4P and USOPTL4-2P USB-to-quad/dual RS-485/422 hubs use the > >> Moschip 7840/7820. For correct operation in RS-485, the chip must be > >> configured in “RS-485 mode” through the scratchpad register as per the > >> datasheet. This strobes the DTR line on transmission, enabling the driver > >> on the RS485 transceiver chip. > > > > I think if you include a config option to do this, you should > > also enable the canonical way of using an ioctl(). That means > > you need to support rs485_config(). > > > > Regards > > Oliver > > > > Thank you for that pointer, I was not familiar with that IOCTL. I will > see what's required for implementation. Yeah, we really don't want to add new module options. Either see if you can make this fit with the rs485 ioctl, or do this based on the driver_data field in the id_table (e.g. set a feature flags there) as we don't want to sprinkle the driver with ID-conditionals. Thanks, Johan -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
