On Wednesday 20 August 2014, Daniel Baluta wrote: > From: Octavian Purdila <octavian.purdila@xxxxxxxxx> > > This patch implements the USB part of the Diolan USB-I2C/SPI/GPIO > Master Adapter DLN-2. Details about the device can be found here: > > https://www.diolan.com/i2c/i2c_interface.html. > > Information about the USB protocol can be found in the Programmer's > Reference Manual [1], see section 1.7. > > Because the hardware has a single transmit endpoint and a single > receive endpoint the communication between the various DLN2 drivers > and the hardware will be muxed/demuxed by this driver. > > The functional DLN2 drivers (i2c, GPIO, etc.) will have to register > themselves as DLN2 modules in order to send or receive data. > > Each DLN2 module will be identified by the handle field within the DLN2 > message header. If a DLN2 module issues multiple commands in parallel > they will be identified by the echo counter field in the message header. > > The DLN2 modules can use the dln2_transfer() function to issue a > command and wait for its response. They can also use an asynchronous > mode of operation, in which case a receive callback function is going > to be notified when messages for a specific handle are received. > > Because the hardware reserves handle 0 for GPIO events, the driver > also reserves handle 0. It will be allocated to a DLN2 module only if > it is explicitly requested. > > [1] https://www.diolan.com/downloads/dln-api-manual.pdf > > Signed-off-by: Octavian Purdila <octavian.purdila@xxxxxxxxx> After a very brief review of the driver, I think this would be better handled as an MFD driver in drivers/mfd that creates child devices and has the high-level drivers get registered as platform_driver. Arnd -- 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
