2 * Copyright (C) 2016-2017 Linaro Ltd., Rob Herring <robh@kernel.org>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 and
6 * only version 2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
13 #ifndef _LINUX_SERDEV_H
14 #define _LINUX_SERDEV_H
16 #include <linux/types.h>
17 #include <linux/device.h>
18 #include <linux/termios.h>
19 #include <linux/delay.h>
21 struct serdev_controller;
25 * serdev device structures
29 * struct serdev_device_ops - Callback operations for a serdev device
30 * @receive_buf: Function called with data received from device.
31 * @write_wakeup: Function called when ready to transmit more data.
33 struct serdev_device_ops {
34 int (*receive_buf)(struct serdev_device *, const unsigned char *, size_t);
35 void (*write_wakeup)(struct serdev_device *);
39 * struct serdev_device - Basic representation of an serdev device
40 * @dev: Driver model representation of the device.
41 * @nr: Device number on serdev bus.
42 * @ctrl: serdev controller managing this device.
43 * @ops: Device operations.
45 struct serdev_device {
48 struct serdev_controller *ctrl;
49 const struct serdev_device_ops *ops;
52 static inline struct serdev_device *to_serdev_device(struct device *d)
54 return container_of(d, struct serdev_device, dev);
58 * struct serdev_device_driver - serdev slave device driver
59 * @driver: serdev device drivers should initialize name field of this
61 * @probe: binds this driver to a serdev device.
62 * @remove: unbinds this driver from the serdev device.
64 struct serdev_device_driver {
65 struct device_driver driver;
66 int (*probe)(struct serdev_device *);
67 void (*remove)(struct serdev_device *);
70 static inline struct serdev_device_driver *to_serdev_device_driver(struct device_driver *d)
72 return container_of(d, struct serdev_device_driver, driver);
76 * serdev controller structures
78 struct serdev_controller_ops {
79 int (*write_buf)(struct serdev_controller *, const unsigned char *, size_t);
80 void (*write_flush)(struct serdev_controller *);
81 int (*write_room)(struct serdev_controller *);
82 int (*open)(struct serdev_controller *);
83 void (*close)(struct serdev_controller *);
84 void (*set_flow_control)(struct serdev_controller *, bool);
85 unsigned int (*set_baudrate)(struct serdev_controller *, unsigned int);
86 void (*wait_until_sent)(struct serdev_controller *, long);
87 int (*get_tiocm)(struct serdev_controller *);
88 int (*set_tiocm)(struct serdev_controller *, unsigned int, unsigned int);
92 * struct serdev_controller - interface to the serdev controller
93 * @dev: Driver model representation of the device.
94 * @nr: number identifier for this controller/bus.
95 * @serdev: Pointer to slave device for this controller.
96 * @ops: Controller operations.
98 struct serdev_controller {
101 struct serdev_device *serdev;
102 const struct serdev_controller_ops *ops;
105 static inline struct serdev_controller *to_serdev_controller(struct device *d)
107 return container_of(d, struct serdev_controller, dev);
110 static inline void *serdev_device_get_drvdata(const struct serdev_device *serdev)
112 return dev_get_drvdata(&serdev->dev);
115 static inline void serdev_device_set_drvdata(struct serdev_device *serdev, void *data)
117 dev_set_drvdata(&serdev->dev, data);
121 * serdev_device_put() - decrement serdev device refcount
122 * @serdev serdev device.
124 static inline void serdev_device_put(struct serdev_device *serdev)
127 put_device(&serdev->dev);
130 static inline void serdev_device_set_client_ops(struct serdev_device *serdev,
131 const struct serdev_device_ops *ops)
137 void *serdev_controller_get_drvdata(const struct serdev_controller *ctrl)
139 return ctrl ? dev_get_drvdata(&ctrl->dev) : NULL;
142 static inline void serdev_controller_set_drvdata(struct serdev_controller *ctrl,
145 dev_set_drvdata(&ctrl->dev, data);
149 * serdev_controller_put() - decrement controller refcount
150 * @ctrl serdev controller.
152 static inline void serdev_controller_put(struct serdev_controller *ctrl)
155 put_device(&ctrl->dev);
158 struct serdev_device *serdev_device_alloc(struct serdev_controller *);
159 int serdev_device_add(struct serdev_device *);
160 void serdev_device_remove(struct serdev_device *);
162 struct serdev_controller *serdev_controller_alloc(struct device *, size_t);
163 int serdev_controller_add(struct serdev_controller *);
164 void serdev_controller_remove(struct serdev_controller *);
166 static inline void serdev_controller_write_wakeup(struct serdev_controller *ctrl)
168 struct serdev_device *serdev = ctrl->serdev;
170 if (!serdev || !serdev->ops->write_wakeup)
173 serdev->ops->write_wakeup(ctrl->serdev);
176 static inline int serdev_controller_receive_buf(struct serdev_controller *ctrl,
177 const unsigned char *data,
180 struct serdev_device *serdev = ctrl->serdev;
182 if (!serdev || !serdev->ops->receive_buf)
185 return serdev->ops->receive_buf(ctrl->serdev, data, count);
188 #if IS_ENABLED(CONFIG_SERIAL_DEV_BUS)
190 int serdev_device_open(struct serdev_device *);
191 void serdev_device_close(struct serdev_device *);
192 unsigned int serdev_device_set_baudrate(struct serdev_device *, unsigned int);
193 void serdev_device_set_flow_control(struct serdev_device *, bool);
194 void serdev_device_wait_until_sent(struct serdev_device *, long);
195 int serdev_device_get_tiocm(struct serdev_device *);
196 int serdev_device_set_tiocm(struct serdev_device *, int, int);
197 int serdev_device_write_buf(struct serdev_device *, const unsigned char *, size_t);
198 void serdev_device_write_flush(struct serdev_device *);
199 int serdev_device_write_room(struct serdev_device *);
202 * serdev device driver functions
204 int __serdev_device_driver_register(struct serdev_device_driver *, struct module *);
205 #define serdev_device_driver_register(sdrv) \
206 __serdev_device_driver_register(sdrv, THIS_MODULE)
209 * serdev_device_driver_unregister() - unregister an serdev client driver
210 * @sdrv: the driver to unregister
212 static inline void serdev_device_driver_unregister(struct serdev_device_driver *sdrv)
215 driver_unregister(&sdrv->driver);
218 #define module_serdev_device_driver(__serdev_device_driver) \
219 module_driver(__serdev_device_driver, serdev_device_driver_register, \
220 serdev_device_driver_unregister)
224 static inline int serdev_device_open(struct serdev_device *sdev)
228 static inline void serdev_device_close(struct serdev_device *sdev) {}
229 static inline unsigned int serdev_device_set_baudrate(struct serdev_device *sdev, unsigned int baudrate)
233 static inline void serdev_device_set_flow_control(struct serdev_device *sdev, bool enable) {}
234 static inline void serdev_device_wait_until_sent(struct serdev_device *sdev, long timeout) {}
235 static inline int serdev_device_get_tiocm(struct serdev_device *serdev)
239 static inline int serdev_device_set_tiocm(struct serdev_device *serdev, int set, int clear)
243 static inline int serdev_device_write_buf(struct serdev_device *sdev, const unsigned char *buf, size_t count)
247 static inline void serdev_device_write_flush(struct serdev_device *sdev) {}
248 static inline int serdev_device_write_room(struct serdev_device *sdev)
253 #define serdev_device_driver_register(x)
254 #define serdev_device_driver_unregister(x)
256 #endif /* CONFIG_SERIAL_DEV_BUS */
258 static inline bool serdev_device_get_cts(struct serdev_device *serdev)
260 int status = serdev_device_get_tiocm(serdev);
261 return !!(status & TIOCM_CTS);
264 static inline int serdev_device_wait_for_cts(struct serdev_device *serdev, bool state, int timeout_ms)
266 unsigned long timeout;
269 timeout = jiffies + msecs_to_jiffies(timeout_ms);
270 while (time_is_after_jiffies(timeout)) {
271 signal = serdev_device_get_cts(serdev);
274 usleep_range(1000, 2000);
280 static inline int serdev_device_set_rts(struct serdev_device *serdev, bool enable)
283 return serdev_device_set_tiocm(serdev, TIOCM_RTS, 0);
285 return serdev_device_set_tiocm(serdev, 0, TIOCM_RTS);
289 * serdev hooks into TTY core
294 #ifdef CONFIG_SERIAL_DEV_CTRL_TTYPORT
295 struct device *serdev_tty_port_register(struct tty_port *port,
296 struct device *parent,
297 struct tty_driver *drv, int idx);
298 void serdev_tty_port_unregister(struct tty_port *port);
300 static inline struct device *serdev_tty_port_register(struct tty_port *port,
301 struct device *parent,
302 struct tty_driver *drv, int idx)
304 return ERR_PTR(-ENODEV);
306 static inline void serdev_tty_port_unregister(struct tty_port *port) {}
307 #endif /* CONFIG_SERIAL_DEV_CTRL_TTYPORT */
309 #endif /*_LINUX_SERDEV_H */