On Thu, Sep 28, 2023 at 08:16:29AM -0700, Max Filippov wrote: > Add driver for the UART controllers of the Espressif ESP32 and ESP32S3 > SoCs. Hardware specification is available at the following URLs: > > https://www.espressif.com/sites/default/files/documentation/esp32_technical_reference_manual_en.pdf > (Chapter 13 UART Controller) > https://www.espressif.com/sites/default/files/documentation/esp32-s3_technical_reference_manual_en.pdf > (Chapter 26 UART Controller) > > Signed-off-by: Max Filippov <jcmvbkbc@xxxxxxxxx> > --- > Changes v2->v3: > - rework brk handling in esp32_uart_rxint > - only increment port->icount.rx in case insert_flip_char() is called > - use HZ instead of msecs_to_jiffies(1000) in esp32_uart_put_char_sync > - add early return to esp32_uart_transmit_buffer > - use request_irq/free_irq instead of devm_* versions > - add blank lines before certain return statements > > Changes v1->v2: > - redefine register fields using BIT and GENMASK > - drop _MASK suffix from register field definitions > - drop *_SHIFT definitions where possible > - drop unused rxfifo_full_thrhd_mask and txfifo_empty_thrhd_mask > - split register reads/writes and bitwise operations into multiple lines > - use u8 instead of unsigned char in internal functions > - add timeout to esp32_uart_put_char_sync > - use uart_port_tx_limited in esp32_uart_transmit_buffer > - use IRQ_RETVAL in esp32_uart_int > - disable clock in esp32_uart_startup in case devm_request_irq fails > - rearrange devm_request_irq with enabling IRQs in the UART registers > - drop empty esp32_uart_release_port and esp32_uart_request_port > - simplify esp32_uart_tx_empty > - mask out unsupported CMSPAR flag in termios->c_cflag in > esp32_uart_set_termios > - invoke uart_update_timeout in esp32_uart_set_termios > - drop MODULE_DESCRIPTION > - rearrange esp32_uart_set_baud: return bool indicating whether baud > rate was set or not, use it in the esp32_uart_set_termios to set the > default 115200 > - turn 'locked' into bool in esp32_uart_console_write > - turn num_read into unsigned int in esp32_uart_earlycon_read > > drivers/tty/serial/Kconfig | 13 + > drivers/tty/serial/Makefile | 1 + > drivers/tty/serial/esp32_uart.c | 741 +++++++++++++++++++++++++++++++ > include/uapi/linux/serial_core.h | 3 + > 4 files changed, 758 insertions(+) > create mode 100644 drivers/tty/serial/esp32_uart.c > > diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig > index bdc568a4ab66..d9ca6b268f01 100644 > --- a/drivers/tty/serial/Kconfig > +++ b/drivers/tty/serial/Kconfig > @@ -1578,6 +1578,19 @@ config SERIAL_NUVOTON_MA35D1_CONSOLE > but you can alter that using a kernel command line option such as > "console=ttyNVTx". > > +config SERIAL_ESP32 > + tristate "Espressif ESP32 UART support" > + depends on XTENSA_PLATFORM_ESP32 || (COMPILE_TEST && OF) > + select SERIAL_CORE > + select SERIAL_CORE_CONSOLE > + select SERIAL_EARLYCON > + help > + Driver for the UART controllers of the Espressif ESP32xx SoCs. > + When earlycon option is enabled the following kernel command line > + snippets may be used: > + earlycon=esp32s3uart,mmio32,0x60000000,115200n8,40000000 > + earlycon=esp32uart,mmio32,0x3ff40000,115200n8 > + > endmenu > > config SERIAL_MCTRL_GPIO > diff --git a/drivers/tty/serial/Makefile b/drivers/tty/serial/Makefile > index 138abbc89738..7b73137df7f3 100644 > --- a/drivers/tty/serial/Makefile > +++ b/drivers/tty/serial/Makefile > @@ -88,6 +88,7 @@ obj-$(CONFIG_SERIAL_MILBEAUT_USIO) += milbeaut_usio.o > obj-$(CONFIG_SERIAL_SIFIVE) += sifive.o > obj-$(CONFIG_SERIAL_LITEUART) += liteuart.o > obj-$(CONFIG_SERIAL_SUNPLUS) += sunplus-uart.o > +obj-$(CONFIG_SERIAL_ESP32) += esp32_uart.o > > # GPIOLIB helpers for modem control lines > obj-$(CONFIG_SERIAL_MCTRL_GPIO) += serial_mctrl_gpio.o > diff --git a/drivers/tty/serial/esp32_uart.c b/drivers/tty/serial/esp32_uart.c > new file mode 100644 > index 000000000000..bb5471e8b6b6 > --- /dev/null > +++ b/drivers/tty/serial/esp32_uart.c > @@ -0,0 +1,741 @@ > +// SPDX-License-Identifier: GPL-2.0-or-later Same license and copyright question as I had on the ACM patch. thanks, greg k-h
