Hi all, Here's v6 set of these patches fixed up for Johan's earlier comments. Getting rid of the custom chardev interface, and making things more generic also simplified things quite a bit. Thanks a lot Johan :) This series does the following: 1. Adds functions to n_gsm.c for serdev-ngsm.c driver to use 2. Adds a generic serdev-ngsm.c driver that brings up the TS 27.010 TTY ports configured in devicetree with help of n_gsm.c 3. Allows the use of standard Linux device drivers for dedicated TS 27.010 channels for devices like GNSS and ALSA found on some modems for example 4. Adds a serdev-ngsm consumer driver for the GNSS device found on the Motorola Mapphone MDM6600 modem on devices like droid4 I've placed the serdev-ngsm.c under drivers/tty/serdev as it still seems to make most sense with no better places available. It's no longer an MFD driver as it really does not need to care what channel specific consumer drivers might be configured. So it now just uses of_platform_populate() to probe whatever child nodes it might find. I'm not attached having the driver in drivers/tty/serdev. I just don't have any better locations in mind. So jsing Johan's earlier i2c example, the drivers/tty/serdev/serdev-ngsm.c driver is now a generic protocol and bus driver, so it's getting closer to the maybe the drivers/i2c/busses analogy :) Please do suggest better locations other than MFD and misc if you have better ideas. Now without the chardev support, the /dev/gsmtty* using apps need to use "U1234AT+CFUN?" format for the packets. The advantage is less kernel code, and we keep the existing /dev/gsmtty* interface. If we still really need the custom chardev support, that can now be added as needed with the channel specific consumer driver(s). My guess is that at least with the pending ofono patches, we just want to use the raw interface for /dev/gsmtty* interface and stop pretending we have a modem that is AT compatible. Regards, Tony Changes since v5: - Based on comments from Johan, moved back to using the existing TS 27.010 TTYs created by n_gsm.c instaed of adding custom chardev support to deal with the Motorola custom protocol - Based on comments from Johan, made the serdev-ngsm driver generic with just minimal quirk handling for the Motorola modem - Dropped the Motorola custom protocol on top of TS 27.010 handling from serdev-ngsm.c as this can now be easily handled by the channel specific drivers as needed - Added few more helpers to n_gsm.c for serdev-ngsm.c to use - Added the channel specific GNSS driver for the Motorola modem Changes since v4: - Use drivers/tty/serdev/protocol directory for the driver instead of drivers/mfd as discussed on the lists for v3 set of patches - Fix remove to call kfree only after removing device from the list Changes since v3: - Update list of folks in Cc, looks like I sent v3 only to Lee and lkml - Init privdata before motmdm_register_dlci calls gsm_serdev_register_dlci - Update binding based on Rob's comments for license and "allOf" Changes since v2: - Drop useless send_command indirection, use static motmdm_send_command Changes since v1: - Simplified usage and got rid of few pointless inline functions - Added consumer MFD driver, devicetree binding, and dts changes Tony Lindgren (6): tty: n_gsm: Add support for serdev drivers dt-bindings: serdev: ngsm: Add binding for serdev-ngsm serdev: ngsm: Add generic serdev-ngsm driver dt-bindings: gnss: Add binding for Motorola Mapphone MDM6600 GNSS gnss: motmdm: Add support for Motorola Mapphone MDM6600 modem ARM: dts: omap4-droid4: Configure modem for serdev-ngsm .../devicetree/bindings/gnss/motmdm.yaml | 29 ++ .../bindings/serdev/serdev-ngsm.yaml | 64 +++ .../devicetree/bindings/vendor-prefixes.yaml | 2 + .../boot/dts/motorola-mapphone-common.dtsi | 14 + drivers/gnss/Kconfig | 8 + drivers/gnss/Makefile | 3 + drivers/gnss/motmdm.c | 419 ++++++++++++++++ drivers/tty/n_gsm.c | 428 +++++++++++++++++ drivers/tty/serdev/Kconfig | 10 + drivers/tty/serdev/Makefile | 1 + drivers/tty/serdev/serdev-ngsm.c | 449 ++++++++++++++++++ include/linux/serdev-gsm.h | 163 +++++++ 12 files changed, 1590 insertions(+) create mode 100644 Documentation/devicetree/bindings/gnss/motmdm.yaml create mode 100644 Documentation/devicetree/bindings/serdev/serdev-ngsm.yaml create mode 100644 drivers/gnss/motmdm.c create mode 100644 drivers/tty/serdev/serdev-ngsm.c create mode 100644 include/linux/serdev-gsm.h -- 2.26.2