diff options
| -rw-r--r-- | drivers/tty/serdev/Kconfig | 8 | ||||
| -rw-r--r-- | drivers/tty/serdev/Makefile | 2 | ||||
| -rw-r--r-- | drivers/tty/serdev/serdev-ttyport.c | 224 | ||||
| -rw-r--r-- | include/linux/serdev.h | 21 |
4 files changed, 255 insertions, 0 deletions
diff --git a/drivers/tty/serdev/Kconfig b/drivers/tty/serdev/Kconfig index 3b6ecd187bef..cdc6b820cf93 100644 --- a/drivers/tty/serdev/Kconfig +++ b/drivers/tty/serdev/Kconfig @@ -6,3 +6,11 @@ menuconfig SERIAL_DEV_BUS help Core support for devices connected via a serial port. +if SERIAL_DEV_BUS + +config SERIAL_DEV_CTRL_TTYPORT + bool "Serial device TTY port controller" + depends on TTY + depends on SERIAL_DEV_BUS != m + +endif diff --git a/drivers/tty/serdev/Makefile b/drivers/tty/serdev/Makefile index 01a9b62183f4..0cbdb9444d9d 100644 --- a/drivers/tty/serdev/Makefile +++ b/drivers/tty/serdev/Makefile @@ -1,3 +1,5 @@ serdev-objs := core.o obj-$(CONFIG_SERIAL_DEV_BUS) += serdev.o + +obj-$(CONFIG_SERIAL_DEV_CTRL_TTYPORT) += serdev-ttyport.o diff --git a/drivers/tty/serdev/serdev-ttyport.c b/drivers/tty/serdev/serdev-ttyport.c new file mode 100644 index 000000000000..683320b81a2b --- /dev/null +++ b/drivers/tty/serdev/serdev-ttyport.c @@ -0,0 +1,224 @@ +/* + * Copyright (C) 2016-2017 Linaro Ltd., Rob Herring <robh@kernel.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ +#include <linux/kernel.h> +#include <linux/serdev.h> +#include <linux/tty.h> +#include <linux/tty_driver.h> + +#define SERPORT_ACTIVE 1 + +struct serport { + struct tty_port *port; + struct tty_struct *tty; + struct tty_driver *tty_drv; + int tty_idx; + unsigned long flags; +}; + +/* + * Callback functions from the tty port. + */ + +static int ttyport_receive_buf(struct tty_port *port, const unsigned char *cp, + const unsigned char *fp, size_t count) +{ + struct serdev_controller *ctrl = port->client_data; + struct serport *serport = serdev_controller_get_drvdata(ctrl); + + if (!test_bit(SERPORT_ACTIVE, &serport->flags)) + return 0; + + return serdev_controller_receive_buf(ctrl, cp, count); +} + +static void ttyport_write_wakeup(struct tty_port *port) +{ + struct serdev_controller *ctrl = port->client_data; + struct serport *serport = serdev_controller_get_drvdata(ctrl); + + if (!test_and_clear_bit(TTY_DO_WRITE_WAKEUP, &port->tty->flags)) + return; + + if (test_bit(SERPORT_ACTIVE, &serport->flags)) + serdev_controller_write_wakeup(ctrl); +} + +static const struct tty_port_client_operations client_ops = { + .receive_buf = ttyport_receive_buf, + .write_wakeup = ttyport_write_wakeup, +}; + +/* + * Callback functions from the serdev core. + */ + +static int ttyport_write_buf(struct serdev_controller *ctrl, const unsigned char *data, size_t len) +{ + struct serport *serport = serdev_controller_get_drvdata(ctrl); + struct tty_struct *tty = serport->tty; + + if (!test_bit(SERPORT_ACTIVE, &serport->flags)) + return 0; + + set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); + return tty->ops->write(serport->tty, data, len); +} + +static void ttyport_write_flush(struct serdev_controller *ctrl) +{ + struct serport *serport = serdev_controller_get_drvdata(ctrl); + struct tty_struct *tty = serport->tty; + + tty_driver_flush_buffer(tty); +} + +static int ttyport_write_room(struct serdev_controller *ctrl) +{ + struct serport *serport = serdev_controller_get_drvdata(ctrl); + struct tty_struct *tty = serport->tty; + + return tty_write_room(tty); +} + +static int ttyport_open(struct serdev_controller *ctrl) +{ + struct serport *serport = serdev_controller_get_drvdata(ctrl); + struct tty_struct *tty; + struct ktermios ktermios; + + tty = tty_init_dev(serport->tty_drv, serport->tty_idx); + serport->tty = tty; + + serport->port->client_ops = &client_ops; + serport->port->client_data = ctrl; + + if (tty->ops->open) + tty->ops->open(serport->tty, NULL); + else + tty_port_open(serport->port, tty, NULL); + + /* Bring the UART into a known 8 bits no parity hw fc state */ + ktermios = tty->termios; + ktermios.c_iflag &= ~(IGNBRK | BRKINT | PARMRK | ISTRIP | + INLCR | IGNCR | ICRNL | IXON); + ktermios.c_oflag &= ~OPOST; + ktermios.c_lflag &= ~(ECHO | ECHONL | ICANON | ISIG | IEXTEN); + ktermios.c_cflag &= ~(CSIZE | PARENB); + ktermios.c_cflag |= CS8; + ktermios.c_cflag |= CRTSCTS; + tty_set_termios(tty, &ktermios); + + set_bit(SERPORT_ACTIVE, &serport->flags); + + tty_unlock(serport->tty); + return 0; +} + +static void ttyport_close(struct serdev_controller *ctrl) +{ + struct serport *serport = serdev_controller_get_drvdata(ctrl); + struct tty_struct *tty = serport->tty; + + clear_bit(SERPORT_ACTIVE, &serport->flags); + + if (tty->ops->close) + tty->ops->close(tty, NULL); + + tty_release_struct(tty, serport->tty_idx); +} + +static unsigned int ttyport_set_baudrate(struct serdev_controller *ctrl, unsigned int speed) +{ + struct serport *serport = serdev_controller_get_drvdata(ctrl); + struct tty_struct *tty = serport->tty; + struct ktermios ktermios = tty->termios; + + ktermios.c_cflag &= ~CBAUD; + tty_termios_encode_baud_rate(&ktermios, speed, speed); + + /* tty_set_termios() return not checked as it is always 0 */ + tty_set_termios(tty, &ktermios); + return speed; +} + +static void ttyport_set_flow_control(struct serdev_controller *ctrl, bool enable) +{ + struct serport *serport = serdev_controller_get_drvdata(ctrl); + struct tty_struct *tty = serport->tty; + struct ktermios ktermios = tty->termios; + + if (enable) + ktermios.c_cflag |= CRTSCTS; + else + ktermios.c_cflag &= ~CRTSCTS; + + tty_set_termios(tty, &ktermios); +} + +static const struct serdev_controller_ops ctrl_ops = { + .write_buf = ttyport_write_buf, + .write_flush = ttyport_write_flush, + .write_room = ttyport_write_room, + .open = ttyport_open, + .close = ttyport_close, + .set_flow_control = ttyport_set_flow_control, + .set_baudrate = ttyport_set_baudrate, +}; + +struct device *serdev_tty_port_register(struct tty_port *port, + struct device *parent, + struct tty_driver *drv, int idx) +{ + struct serdev_controller *ctrl; + struct serport *serport; + int ret; + + if (!port || !drv || !parent) + return ERR_PTR(-ENODEV); + + ctrl = serdev_controller_alloc(parent, sizeof(struct serport)); + if (!ctrl) + return ERR_PTR(-ENOMEM); + serport = serdev_controller_get_drvdata(ctrl); + + serport->port = port; + serport->tty_idx = idx; + serport->tty_drv = drv; + + ctrl->ops = &ctrl_ops; + + ret = serdev_controller_add(ctrl); + if (ret) + goto err_controller_put; + + dev_info(&ctrl->dev, "tty port %s%d registered\n", drv->name, idx); + return &ctrl->dev; + +err_controller_put: + serdev_controller_put(ctrl); + return ERR_PTR(ret); +} + +void serdev_tty_port_unregister(struct tty_port *port) +{ + struct serdev_controller *ctrl = port->client_data; + struct serport *serport = serdev_controller_get_drvdata(ctrl); + + if (!serport) + return; + + serdev_controller_remove(ctrl); + port->client_ops = NULL; + port->client_data = NULL; + serdev_controller_put(ctrl); +} diff --git a/include/linux/serdev.h b/include/linux/serdev.h index 3ac26c1a8aab..9519da6253a8 100644 --- a/include/linux/serdev.h +++ b/include/linux/serdev.h @@ -238,4 +238,25 @@ static inline int serdev_device_write_room(struct serdev_device *sdev) #endif /* CONFIG_SERIAL_DEV_BUS */ +/* + * serdev hooks into TTY core + */ +struct tty_port; +struct tty_driver; + +#ifdef CONFIG_SERIAL_DEV_CTRL_TTYPORT +struct device *serdev_tty_port_register(struct tty_port *port, + struct device *parent, + struct tty_driver *drv, int idx); +void serdev_tty_port_unregister(struct tty_port *port); +#else +static inline struct device *serdev_tty_port_register(struct tty_port *port, + struct device *parent, + struct tty_driver *drv, int idx) +{ + return ERR_PTR(-ENODEV); +} +static inline void serdev_tty_port_unregister(struct tty_port *port) {} +#endif /* CONFIG_SERIAL_DEV_CTRL_TTYPORT */ + #endif /*_LINUX_SERDEV_H */ |