Hello, This is the 11th version of driver. I added a mfd driver which by default probes atmel_serial driver and if in dt is specified to probe the spi driver, then the spi-at91-usart driver will be probed. The compatible for atmel_serial is now the compatible for at91-usart mfd driver and compatilbe for atmel_serial driver was changed in order to keep the bindings for serial as they are. @Lee, could you take this patch series into your tree? I addressed all Mark remarks. In this resend I changed my email address from MAINTAINERS file. Changes in v11: - removed "depends on HAS_DMA" from drivers/spi/Kconfig because the driver has no dma support - changed "selects MFD_AT91_USART" to "depends on MFD_AT91_USART" in drivers/spi/Kconfig - changed comment style in spi-at91-usart.c Changes in v10: -fixed kbuild test robot warning Changes in v9: - minor changes - rebased on top of broonie/for-4.19 Changes in v8: - fixed passing an empty mfd cell if "atmel,usart-mode" value is invalid Changes in v7: - synced up SPDIX license with module license - numbering of usart modes starts from 0 insteand of 1 Changes in v6: - removed unused compatible strings from serial and spi drivers Changes in v5: - fixed usage of stdout-path property with atmel_serial driver Changes in v4: - modified the spi driver to use cs gpio support form spi subsystem - fixed dma transfers for serial driver - squashed binding for spi and serial and moved them to mfd/atmel-usart.txt Changes in v3: - fixed spi slaves probing Changes in v2: - added at91-usart mfd driver - modified spi-at91-usart driver to work as mfd driver child - modified atmel_serial driver to work as mfd driver child Changes in v1: - added spi-at91-usart driver Radu Pirea (6): MAINTAINERS: add at91 usart mfd driver dt-bindings: add binding for atmel-usart in SPI mode mfd: at91-usart: added mfd driver for usart MAINTAINERS: add at91 usart spi driver spi: at91-usart: add driver for at91-usart as spi tty/serial: atmel: change the driver to work under at91-usart mfd .../bindings/{serial => mfd}/atmel-usart.txt | 25 +- MAINTAINERS | 16 + drivers/mfd/Kconfig | 9 + drivers/mfd/Makefile | 1 + drivers/mfd/at91-usart.c | 71 +++ drivers/spi/Kconfig | 8 + drivers/spi/Makefile | 1 + drivers/spi/spi-at91-usart.c | 432 ++++++++++++++++++ drivers/tty/serial/Kconfig | 1 + drivers/tty/serial/atmel_serial.c | 42 +- include/dt-bindings/mfd/at91-usart.h | 17 + 11 files changed, 606 insertions(+), 17 deletions(-) rename Documentation/devicetree/bindings/{serial => mfd}/atmel-usart.txt (76%) create mode 100644 drivers/mfd/at91-usart.c create mode 100644 drivers/spi/spi-at91-usart.c create mode 100644 include/dt-bindings/mfd/at91-usart.h -- 2.18.0