On Wed, Feb 26, 2020 at 06:43:08AM -0800, Tony Lindgren wrote: > * Lee Jones <lee.jones@xxxxxxxxxx> [200226 11:56]: > > On Thu, 20 Feb 2020, Tony Lindgren wrote: > > > > > Many Motorola phones are controlling the modem using a custom variant > > > of TS 27.010 serial line discipline. Devices on these modems have a > > > dedicated TS 27.010 channel for features like audio mixer, GNSS, voice > > > modem, SIM card reader and so on. > > > > > > This driver allows using various devices on the modem. In order to do > > > that, we need to take care of the following three things: > > > > > > 1. Provide /dev/motmdm* character devices for apps to use for talking > > > to the various devices on the modem > > > > > > 2. Handle Motorola custom protocol over TS 27.010 to make the channels > > > usable for userspace > > > > > > 3. Coordinate PM runtime with the USB PHY because of shared GPIO pins > > > with the USB PHY > ... > > > --- > > > drivers/mfd/Kconfig | 9 + > > > drivers/mfd/Makefile | 1 + > > > drivers/mfd/motorola-mdm.c | 1200 ++++++++++++++++++++++++++++++++++++ > > > > I'm not even going to start reviewing this as I can see, without even > > looking at the code, that this has too much functionality (stuff that > > does stuff) contained. > > > > Please move as much functionality out into the subsystems as > > possible. Ideally, MFDs should be responsible for obtaining and > > registering shared resources and registering child devices. Anything > > else should be shifted out to an appropriate subsystem. > > > > MFD is not Misc. > > OK good point. So this is a serdev consumer driver that eventually will > also provide serdev style access to few device drivers too for the > device within the modem after decoding the Motorola specific protocol. > No special need for this driver to be under drivers/mfd though. > > How about we add drivers/tty/serdev/protocol or similar directory for > drivers like this? Sure, that seems sane.
