There are some situations where it is interesting to load/remove serdev devices dynamically, like during board bring-up or when we are developing a new driver or for devices that are neither described via ACPI or device tree. This implementation allows the creation of serdev devices via sysfs, in a similar way as the i2c bus allows sysfs instantiation [1]. It also opens the door to create platform drivers for specific platforms, such us notebooks or industrial computers, when their serial devices are not described via DT or ACPI. This patchset also supports automatic module load via udev/modprobe, simplifying its use by the final user. Currently, serdev does not manage ports that do not have a serdev device defined at boot time. This implementation adds a new serdev module, ttydev, that provides the same functionality of tty (it calls the original one), but can be unloaded. TL/DR: When we want to create a new device, we just run: root@qt5022:~# echo ttydev > /sys/bus/serial/devices/serial0/new_device This will create a new device: root@qt5022:~# ls /sys/bus/serial/devices/serial0-0/ driver modalias power subsystem tty uevent And load the required driver to use it: root@qt5022:~# lsmod | grep serdev_ttydev serdev_ttydev 16384 0 The device can be removed: root@qt5022:~# echo serial0-0 > /sys/bus/serial/devices/serial0/delete_device And now we can connect a new device: root@qt5022:~# echo hci-ti > /sys/bus/serial/devices/serial0/new_device [1] https://www.kernel.org/doc/Documentation/i2c/instantiating-devices Ricardo Ribalda Delgado (19): serdev: Add id_table to serdev_device_driver Bluetooth: hci_bcm: Add serdev_id_table Bluetooth: hci_ll: Add serdev_id_table Bluetooth: hci_nokia: Add serdev_id_table serdev: Introduce modalias field serdev: Support bus matching with modalias field serdev: Allows dynamic creation of devices via sysfs serdev: Provide modalias attribute for modalias devices serdev: Provide modalias uevent for modalias devices file2alias: Support for serdev devices Bluetooth: hci_bcm: MODULE_DEVICE_TABLE(serdev) Bluetooth: hci_ll: MODULE_DEVICE_TABLE(serdev) Bluetooth: hci_nokia: MODULE_DEVICE_TABLE(serdev) mfd: rave-sp: MODULE_DEVICE_TABLE(serdev) net: qualcomm: MODULE_DEVICE_TABLE(serdev) serdev: ttyport: Move serport structure to its own header serdev: Mark controllers compatible with ttyport serdev: ttydev: Serdev driver that creates an standard TTY port serdev: Instantiate a ttydev serdev if acpi and of fails drivers/bluetooth/hci_bcm.c | 8 ++ drivers/bluetooth/hci_ll.c | 19 ++++ drivers/bluetooth/hci_nokia.c | 8 ++ drivers/mfd/rave-sp.c | 7 ++ drivers/net/ethernet/qualcomm/qca_uart.c | 7 ++ drivers/tty/serdev/Kconfig | 11 ++ drivers/tty/serdev/Makefile | 2 + drivers/tty/serdev/core.c | 133 +++++++++++++++++++++-- drivers/tty/serdev/serdev-ttydev.c | 70 ++++++++++++ drivers/tty/serdev/serdev-ttyport.c | 10 +- drivers/tty/serdev/serport.h | 16 +++ include/linux/mod_devicetable.h | 10 ++ include/linux/serdev.h | 4 + scripts/mod/devicetable-offsets.c | 3 + scripts/mod/file2alias.c | 11 ++ 15 files changed, 304 insertions(+), 15 deletions(-) create mode 100644 drivers/tty/serdev/serdev-ttydev.c create mode 100644 drivers/tty/serdev/serport.h -- 2.17.0 -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
