Linux kernel mirror (for testing)
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linux
1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Copyright (C) 2016-2017 Linaro Ltd., Rob Herring <robh@kernel.org>
4 */
5#ifndef _LINUX_SERDEV_H
6#define _LINUX_SERDEV_H
7
8#include <linux/types.h>
9#include <linux/device.h>
10#include <linux/iopoll.h>
11#include <linux/uaccess.h>
12#include <linux/termios.h>
13#include <linux/delay.h>
14
15struct serdev_controller;
16struct serdev_device;
17
18/*
19 * serdev device structures
20 */
21
22/**
23 * struct serdev_device_ops - Callback operations for a serdev device
24 * @receive_buf: Function called with data received from device;
25 * returns number of bytes accepted; may sleep.
26 * @write_wakeup: Function called when ready to transmit more data; must
27 * not sleep.
28 */
29struct serdev_device_ops {
30 size_t (*receive_buf)(struct serdev_device *, const u8 *, size_t);
31 void (*write_wakeup)(struct serdev_device *);
32};
33
34/**
35 * struct serdev_device - Basic representation of an serdev device
36 * @dev: Driver model representation of the device.
37 * @nr: Device number on serdev bus.
38 * @ctrl: serdev controller managing this device.
39 * @ops: Device operations.
40 * @write_comp Completion used by serdev_device_write() internally
41 * @write_lock Lock to serialize access when writing data
42 */
43struct serdev_device {
44 struct device dev;
45 int nr;
46 struct serdev_controller *ctrl;
47 const struct serdev_device_ops *ops;
48 struct completion write_comp;
49 struct mutex write_lock;
50};
51
52static inline struct serdev_device *to_serdev_device(struct device *d)
53{
54 return container_of(d, struct serdev_device, dev);
55}
56
57/**
58 * struct serdev_device_driver - serdev slave device driver
59 * @driver: serdev device drivers should initialize name field of this
60 * structure.
61 * @probe: binds this driver to a serdev device.
62 * @remove: unbinds this driver from the serdev device.
63 */
64struct serdev_device_driver {
65 struct device_driver driver;
66 int (*probe)(struct serdev_device *);
67 void (*remove)(struct serdev_device *);
68 void (*shutdown)(struct serdev_device *);
69};
70
71static inline struct serdev_device_driver *to_serdev_device_driver(struct device_driver *d)
72{
73 return container_of(d, struct serdev_device_driver, driver);
74}
75
76enum serdev_parity {
77 SERDEV_PARITY_NONE,
78 SERDEV_PARITY_EVEN,
79 SERDEV_PARITY_ODD,
80};
81
82/*
83 * serdev controller structures
84 */
85struct serdev_controller_ops {
86 ssize_t (*write_buf)(struct serdev_controller *, const u8 *, size_t);
87 void (*write_flush)(struct serdev_controller *);
88 int (*open)(struct serdev_controller *);
89 void (*close)(struct serdev_controller *);
90 void (*set_flow_control)(struct serdev_controller *, bool);
91 int (*set_parity)(struct serdev_controller *, enum serdev_parity);
92 unsigned int (*set_baudrate)(struct serdev_controller *, unsigned int);
93 void (*wait_until_sent)(struct serdev_controller *, long);
94 int (*get_tiocm)(struct serdev_controller *);
95 int (*set_tiocm)(struct serdev_controller *, unsigned int, unsigned int);
96 int (*break_ctl)(struct serdev_controller *ctrl, unsigned int break_state);
97};
98
99/**
100 * struct serdev_controller - interface to the serdev controller
101 * @dev: Driver model representation of the device.
102 * @host: Serial port hardware controller device
103 * @nr: number identifier for this controller/bus.
104 * @serdev: Pointer to slave device for this controller.
105 * @ops: Controller operations.
106 */
107struct serdev_controller {
108 struct device dev;
109 struct device *host;
110 unsigned int nr;
111 struct serdev_device *serdev;
112 const struct serdev_controller_ops *ops;
113};
114
115static inline struct serdev_controller *to_serdev_controller(struct device *d)
116{
117 return container_of(d, struct serdev_controller, dev);
118}
119
120static inline void *serdev_device_get_drvdata(const struct serdev_device *serdev)
121{
122 return dev_get_drvdata(&serdev->dev);
123}
124
125static inline void serdev_device_set_drvdata(struct serdev_device *serdev, void *data)
126{
127 dev_set_drvdata(&serdev->dev, data);
128}
129
130/**
131 * serdev_device_put() - decrement serdev device refcount
132 * @serdev serdev device.
133 */
134static inline void serdev_device_put(struct serdev_device *serdev)
135{
136 if (serdev)
137 put_device(&serdev->dev);
138}
139
140static inline void serdev_device_set_client_ops(struct serdev_device *serdev,
141 const struct serdev_device_ops *ops)
142{
143 serdev->ops = ops;
144}
145
146static inline
147void *serdev_controller_get_drvdata(const struct serdev_controller *ctrl)
148{
149 return ctrl ? dev_get_drvdata(&ctrl->dev) : NULL;
150}
151
152static inline void serdev_controller_set_drvdata(struct serdev_controller *ctrl,
153 void *data)
154{
155 dev_set_drvdata(&ctrl->dev, data);
156}
157
158/**
159 * serdev_controller_put() - decrement controller refcount
160 * @ctrl serdev controller.
161 */
162static inline void serdev_controller_put(struct serdev_controller *ctrl)
163{
164 if (ctrl)
165 put_device(&ctrl->dev);
166}
167
168struct serdev_device *serdev_device_alloc(struct serdev_controller *);
169int serdev_device_add(struct serdev_device *);
170void serdev_device_remove(struct serdev_device *);
171
172struct serdev_controller *serdev_controller_alloc(struct device *host,
173 struct device *parent,
174 size_t size);
175int serdev_controller_add(struct serdev_controller *);
176void serdev_controller_remove(struct serdev_controller *);
177
178static inline void serdev_controller_write_wakeup(struct serdev_controller *ctrl)
179{
180 struct serdev_device *serdev = ctrl->serdev;
181
182 if (!serdev || !serdev->ops->write_wakeup)
183 return;
184
185 serdev->ops->write_wakeup(serdev);
186}
187
188static inline size_t serdev_controller_receive_buf(struct serdev_controller *ctrl,
189 const u8 *data,
190 size_t count)
191{
192 struct serdev_device *serdev = ctrl->serdev;
193
194 if (!serdev || !serdev->ops->receive_buf)
195 return 0;
196
197 return serdev->ops->receive_buf(serdev, data, count);
198}
199
200#if IS_ENABLED(CONFIG_SERIAL_DEV_BUS)
201
202int serdev_device_open(struct serdev_device *);
203void serdev_device_close(struct serdev_device *);
204int devm_serdev_device_open(struct device *, struct serdev_device *);
205unsigned int serdev_device_set_baudrate(struct serdev_device *, unsigned int);
206void serdev_device_set_flow_control(struct serdev_device *, bool);
207int serdev_device_write_buf(struct serdev_device *, const u8 *, size_t);
208void serdev_device_wait_until_sent(struct serdev_device *, long);
209int serdev_device_get_tiocm(struct serdev_device *);
210int serdev_device_set_tiocm(struct serdev_device *, int, int);
211int serdev_device_break_ctl(struct serdev_device *serdev, int break_state);
212void serdev_device_write_wakeup(struct serdev_device *);
213ssize_t serdev_device_write(struct serdev_device *, const u8 *, size_t, long);
214void serdev_device_write_flush(struct serdev_device *);
215
216/*
217 * serdev device driver functions
218 */
219int __serdev_device_driver_register(struct serdev_device_driver *, struct module *);
220#define serdev_device_driver_register(sdrv) \
221 __serdev_device_driver_register(sdrv, THIS_MODULE)
222
223/**
224 * serdev_device_driver_unregister() - unregister an serdev client driver
225 * @sdrv: the driver to unregister
226 */
227static inline void serdev_device_driver_unregister(struct serdev_device_driver *sdrv)
228{
229 if (sdrv)
230 driver_unregister(&sdrv->driver);
231}
232
233#define module_serdev_device_driver(__serdev_device_driver) \
234 module_driver(__serdev_device_driver, serdev_device_driver_register, \
235 serdev_device_driver_unregister)
236
237#else
238
239static inline int serdev_device_open(struct serdev_device *sdev)
240{
241 return -ENODEV;
242}
243static inline void serdev_device_close(struct serdev_device *sdev) {}
244static inline unsigned int serdev_device_set_baudrate(struct serdev_device *sdev, unsigned int baudrate)
245{
246 return 0;
247}
248static inline void serdev_device_set_flow_control(struct serdev_device *sdev, bool enable) {}
249static inline int serdev_device_write_buf(struct serdev_device *serdev,
250 const u8 *buf,
251 size_t count)
252{
253 return -ENODEV;
254}
255static inline void serdev_device_wait_until_sent(struct serdev_device *sdev, long timeout) {}
256static inline int serdev_device_get_tiocm(struct serdev_device *serdev)
257{
258 return -EOPNOTSUPP;
259}
260static inline int serdev_device_set_tiocm(struct serdev_device *serdev, int set, int clear)
261{
262 return -EOPNOTSUPP;
263}
264static inline int serdev_device_break_ctl(struct serdev_device *serdev, int break_state)
265{
266 return -EOPNOTSUPP;
267}
268static inline ssize_t serdev_device_write(struct serdev_device *sdev,
269 const u8 *buf, size_t count,
270 unsigned long timeout)
271{
272 return -ENODEV;
273}
274static inline void serdev_device_write_flush(struct serdev_device *sdev) {}
275
276#define serdev_device_driver_register(x)
277#define serdev_device_driver_unregister(x)
278
279#endif /* CONFIG_SERIAL_DEV_BUS */
280
281static inline bool serdev_device_get_cts(struct serdev_device *serdev)
282{
283 int status = serdev_device_get_tiocm(serdev);
284 return !!(status & TIOCM_CTS);
285}
286
287static inline int serdev_device_wait_for_cts(struct serdev_device *serdev, bool state, int timeout_ms)
288{
289 bool signal;
290
291 return readx_poll_timeout(serdev_device_get_cts, serdev, signal, signal == state,
292 2000, timeout_ms * 1000);
293}
294
295static inline int serdev_device_set_rts(struct serdev_device *serdev, bool enable)
296{
297 if (enable)
298 return serdev_device_set_tiocm(serdev, TIOCM_RTS, 0);
299 else
300 return serdev_device_set_tiocm(serdev, 0, TIOCM_RTS);
301}
302
303int serdev_device_set_parity(struct serdev_device *serdev,
304 enum serdev_parity parity);
305
306/*
307 * serdev hooks into TTY core
308 */
309struct tty_port;
310struct tty_driver;
311
312#ifdef CONFIG_SERIAL_DEV_CTRL_TTYPORT
313struct device *serdev_tty_port_register(struct tty_port *port,
314 struct device *host,
315 struct device *parent,
316 struct tty_driver *drv, int idx);
317int serdev_tty_port_unregister(struct tty_port *port);
318#else
319static inline struct device *serdev_tty_port_register(struct tty_port *port,
320 struct device *host,
321 struct device *parent,
322 struct tty_driver *drv, int idx)
323{
324 return ERR_PTR(-ENODEV);
325}
326static inline int serdev_tty_port_unregister(struct tty_port *port)
327{
328 return -ENODEV;
329}
330#endif /* CONFIG_SERIAL_DEV_CTRL_TTYPORT */
331
332struct acpi_resource;
333struct acpi_resource_uart_serialbus;
334
335#ifdef CONFIG_ACPI
336bool serdev_acpi_get_uart_resource(struct acpi_resource *ares,
337 struct acpi_resource_uart_serialbus **uart);
338#else
339static inline bool serdev_acpi_get_uart_resource(struct acpi_resource *ares,
340 struct acpi_resource_uart_serialbus **uart)
341{
342 return false;
343}
344#endif /* CONFIG_ACPI */
345
346#endif /*_LINUX_SERDEV_H */