| /* |
| * 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. |
| */ |
| #ifndef _LINUX_SERDEV_H |
| #define _LINUX_SERDEV_H |
| |
| #include <linux/types.h> |
| #include <linux/device.h> |
| #include <linux/termios.h> |
| #include <linux/delay.h> |
| |
| struct serdev_controller; |
| struct serdev_device; |
| |
| /* |
| * serdev device structures |
| */ |
| |
| /** |
| * struct serdev_device_ops - Callback operations for a serdev device |
| * @receive_buf: Function called with data received from device. |
| * @write_wakeup: Function called when ready to transmit more data. |
| */ |
| struct serdev_device_ops { |
| int (*receive_buf)(struct serdev_device *, const unsigned char *, size_t); |
| void (*write_wakeup)(struct serdev_device *); |
| }; |
| |
| /** |
| * struct serdev_device - Basic representation of an serdev device |
| * @dev: Driver model representation of the device. |
| * @nr: Device number on serdev bus. |
| * @ctrl: serdev controller managing this device. |
| * @ops: Device operations. |
| * @write_comp Completion used by serdev_device_write() internally |
| * @write_lock Lock to serialize access when writing data |
| */ |
| struct serdev_device { |
| struct device dev; |
| int nr; |
| struct serdev_controller *ctrl; |
| const struct serdev_device_ops *ops; |
| struct completion write_comp; |
| struct mutex write_lock; |
| }; |
| |
| static inline struct serdev_device *to_serdev_device(struct device *d) |
| { |
| return container_of(d, struct serdev_device, dev); |
| } |
| |
| /** |
| * struct serdev_device_driver - serdev slave device driver |
| * @driver: serdev device drivers should initialize name field of this |
| * structure. |
| * @probe: binds this driver to a serdev device. |
| * @remove: unbinds this driver from the serdev device. |
| */ |
| struct serdev_device_driver { |
| struct device_driver driver; |
| int (*probe)(struct serdev_device *); |
| void (*remove)(struct serdev_device *); |
| }; |
| |
| static inline struct serdev_device_driver *to_serdev_device_driver(struct device_driver *d) |
| { |
| return container_of(d, struct serdev_device_driver, driver); |
| } |
| |
| /* |
| * serdev controller structures |
| */ |
| struct serdev_controller_ops { |
| int (*write_buf)(struct serdev_controller *, const unsigned char *, size_t); |
| void (*write_flush)(struct serdev_controller *); |
| int (*write_room)(struct serdev_controller *); |
| int (*open)(struct serdev_controller *); |
| void (*close)(struct serdev_controller *); |
| void (*set_flow_control)(struct serdev_controller *, bool); |
| unsigned int (*set_baudrate)(struct serdev_controller *, unsigned int); |
| void (*wait_until_sent)(struct serdev_controller *, long); |
| int (*get_tiocm)(struct serdev_controller *); |
| int (*set_tiocm)(struct serdev_controller *, unsigned int, unsigned int); |
| }; |
| |
| /** |
| * struct serdev_controller - interface to the serdev controller |
| * @dev: Driver model representation of the device. |
| * @nr: number identifier for this controller/bus. |
| * @serdev: Pointer to slave device for this controller. |
| * @ops: Controller operations. |
| */ |
| struct serdev_controller { |
| struct device dev; |
| unsigned int nr; |
| struct serdev_device *serdev; |
| const struct serdev_controller_ops *ops; |
| }; |
| |
| static inline struct serdev_controller *to_serdev_controller(struct device *d) |
| { |
| return container_of(d, struct serdev_controller, dev); |
| } |
| |
| static inline void *serdev_device_get_drvdata(const struct serdev_device *serdev) |
| { |
| return dev_get_drvdata(&serdev->dev); |
| } |
| |
| static inline void serdev_device_set_drvdata(struct serdev_device *serdev, void *data) |
| { |
| dev_set_drvdata(&serdev->dev, data); |
| } |
| |
| /** |
| * serdev_device_put() - decrement serdev device refcount |
| * @serdev serdev device. |
| */ |
| static inline void serdev_device_put(struct serdev_device *serdev) |
| { |
| if (serdev) |
| put_device(&serdev->dev); |
| } |
| |
| static inline void serdev_device_set_client_ops(struct serdev_device *serdev, |
| const struct serdev_device_ops *ops) |
| { |
| serdev->ops = ops; |
| } |
| |
| static inline |
| void *serdev_controller_get_drvdata(const struct serdev_controller *ctrl) |
| { |
| return ctrl ? dev_get_drvdata(&ctrl->dev) : NULL; |
| } |
| |
| static inline void serdev_controller_set_drvdata(struct serdev_controller *ctrl, |
| void *data) |
| { |
| dev_set_drvdata(&ctrl->dev, data); |
| } |
| |
| /** |
| * serdev_controller_put() - decrement controller refcount |
| * @ctrl serdev controller. |
| */ |
| static inline void serdev_controller_put(struct serdev_controller *ctrl) |
| { |
| if (ctrl) |
| put_device(&ctrl->dev); |
| } |
| |
| struct serdev_device *serdev_device_alloc(struct serdev_controller *); |
| int serdev_device_add(struct serdev_device *); |
| void serdev_device_remove(struct serdev_device *); |
| |
| struct serdev_controller *serdev_controller_alloc(struct device *, size_t); |
| int serdev_controller_add(struct serdev_controller *); |
| void serdev_controller_remove(struct serdev_controller *); |
| |
| static inline void serdev_controller_write_wakeup(struct serdev_controller *ctrl) |
| { |
| struct serdev_device *serdev = ctrl->serdev; |
| |
| if (!serdev || !serdev->ops->write_wakeup) |
| return; |
| |
| serdev->ops->write_wakeup(serdev); |
| } |
| |
| static inline int serdev_controller_receive_buf(struct serdev_controller *ctrl, |
| const unsigned char *data, |
| size_t count) |
| { |
| struct serdev_device *serdev = ctrl->serdev; |
| |
| if (!serdev || !serdev->ops->receive_buf) |
| return -EINVAL; |
| |
| return serdev->ops->receive_buf(serdev, data, count); |
| } |
| |
| #if IS_ENABLED(CONFIG_SERIAL_DEV_BUS) |
| |
| int serdev_device_open(struct serdev_device *); |
| void serdev_device_close(struct serdev_device *); |
| unsigned int serdev_device_set_baudrate(struct serdev_device *, unsigned int); |
| void serdev_device_set_flow_control(struct serdev_device *, bool); |
| void serdev_device_wait_until_sent(struct serdev_device *, long); |
| int serdev_device_get_tiocm(struct serdev_device *); |
| int serdev_device_set_tiocm(struct serdev_device *, int, int); |
| void serdev_device_write_wakeup(struct serdev_device *); |
| int serdev_device_write(struct serdev_device *, const unsigned char *, size_t, unsigned long); |
| void serdev_device_write_flush(struct serdev_device *); |
| int serdev_device_write_room(struct serdev_device *); |
| |
| /* |
| * serdev device driver functions |
| */ |
| int __serdev_device_driver_register(struct serdev_device_driver *, struct module *); |
| #define serdev_device_driver_register(sdrv) \ |
| __serdev_device_driver_register(sdrv, THIS_MODULE) |
| |
| /** |
| * serdev_device_driver_unregister() - unregister an serdev client driver |
| * @sdrv: the driver to unregister |
| */ |
| static inline void serdev_device_driver_unregister(struct serdev_device_driver *sdrv) |
| { |
| if (sdrv) |
| driver_unregister(&sdrv->driver); |
| } |
| |
| #define module_serdev_device_driver(__serdev_device_driver) \ |
| module_driver(__serdev_device_driver, serdev_device_driver_register, \ |
| serdev_device_driver_unregister) |
| |
| #else |
| |
| static inline int serdev_device_open(struct serdev_device *sdev) |
| { |
| return -ENODEV; |
| } |
| static inline void serdev_device_close(struct serdev_device *sdev) {} |
| static inline unsigned int serdev_device_set_baudrate(struct serdev_device *sdev, unsigned int baudrate) |
| { |
| return 0; |
| } |
| static inline void serdev_device_set_flow_control(struct serdev_device *sdev, bool enable) {} |
| static inline void serdev_device_wait_until_sent(struct serdev_device *sdev, long timeout) {} |
| static inline int serdev_device_get_tiocm(struct serdev_device *serdev) |
| { |
| return -ENOTSUPP; |
| } |
| static inline int serdev_device_set_tiocm(struct serdev_device *serdev, int set, int clear) |
| { |
| return -ENOTSUPP; |
| } |
| static inline int serdev_device_write(struct serdev_device *sdev, const unsigned char *buf, |
| size_t count, unsigned long timeout) |
| { |
| return -ENODEV; |
| } |
| static inline void serdev_device_write_flush(struct serdev_device *sdev) {} |
| static inline int serdev_device_write_room(struct serdev_device *sdev) |
| { |
| return 0; |
| } |
| |
| #define serdev_device_driver_register(x) |
| #define serdev_device_driver_unregister(x) |
| |
| #endif /* CONFIG_SERIAL_DEV_BUS */ |
| |
| static inline bool serdev_device_get_cts(struct serdev_device *serdev) |
| { |
| int status = serdev_device_get_tiocm(serdev); |
| return !!(status & TIOCM_CTS); |
| } |
| |
| static inline int serdev_device_wait_for_cts(struct serdev_device *serdev, bool state, int timeout_ms) |
| { |
| unsigned long timeout; |
| bool signal; |
| |
| timeout = jiffies + msecs_to_jiffies(timeout_ms); |
| while (time_is_after_jiffies(timeout)) { |
| signal = serdev_device_get_cts(serdev); |
| if (signal == state) |
| return 0; |
| usleep_range(1000, 2000); |
| } |
| |
| return -ETIMEDOUT; |
| } |
| |
| static inline int serdev_device_set_rts(struct serdev_device *serdev, bool enable) |
| { |
| if (enable) |
| return serdev_device_set_tiocm(serdev, TIOCM_RTS, 0); |
| else |
| return serdev_device_set_tiocm(serdev, 0, TIOCM_RTS); |
| } |
| |
| /* |
| * 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 */ |
| |
| static inline int serdev_device_write_buf(struct serdev_device *serdev, |
| const unsigned char *data, |
| size_t count) |
| { |
| return serdev_device_write(serdev, data, count, 0); |
| } |
| |
| #endif /*_LINUX_SERDEV_H */ |