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 | |
15 | struct serdev_controller; |
16 | struct 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 | */ |
29 | struct serdev_device_ops { |
30 | int (*receive_buf)(struct serdev_device *, const unsigned char *, 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 | */ |
43 | struct 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 | |
52 | static 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 | */ |
64 | struct serdev_device_driver { |
65 | struct device_driver driver; |
66 | int (*probe)(struct serdev_device *); |
67 | void (*remove)(struct serdev_device *); |
68 | }; |
69 | |
70 | static inline struct serdev_device_driver *to_serdev_device_driver(struct device_driver *d) |
71 | { |
72 | return container_of(d, struct serdev_device_driver, driver); |
73 | } |
74 | |
75 | enum serdev_parity { |
76 | SERDEV_PARITY_NONE, |
77 | SERDEV_PARITY_EVEN, |
78 | SERDEV_PARITY_ODD, |
79 | }; |
80 | |
81 | /* |
82 | * serdev controller structures |
83 | */ |
84 | struct serdev_controller_ops { |
85 | int (*write_buf)(struct serdev_controller *, const unsigned char *, size_t); |
86 | void (*write_flush)(struct serdev_controller *); |
87 | int (*write_room)(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 | * @nr: number identifier for this controller/bus. |
103 | * @serdev: Pointer to slave device for this controller. |
104 | * @ops: Controller operations. |
105 | */ |
106 | struct serdev_controller { |
107 | struct device dev; |
108 | unsigned int nr; |
109 | struct serdev_device *serdev; |
110 | const struct serdev_controller_ops *ops; |
111 | }; |
112 | |
113 | static inline struct serdev_controller *to_serdev_controller(struct device *d) |
114 | { |
115 | return container_of(d, struct serdev_controller, dev); |
116 | } |
117 | |
118 | static inline void *serdev_device_get_drvdata(const struct serdev_device *serdev) |
119 | { |
120 | return dev_get_drvdata(dev: &serdev->dev); |
121 | } |
122 | |
123 | static inline void serdev_device_set_drvdata(struct serdev_device *serdev, void *data) |
124 | { |
125 | dev_set_drvdata(dev: &serdev->dev, data); |
126 | } |
127 | |
128 | /** |
129 | * serdev_device_put() - decrement serdev device refcount |
130 | * @serdev serdev device. |
131 | */ |
132 | static inline void serdev_device_put(struct serdev_device *serdev) |
133 | { |
134 | if (serdev) |
135 | put_device(dev: &serdev->dev); |
136 | } |
137 | |
138 | static inline void serdev_device_set_client_ops(struct serdev_device *serdev, |
139 | const struct serdev_device_ops *ops) |
140 | { |
141 | serdev->ops = ops; |
142 | } |
143 | |
144 | static inline |
145 | void *serdev_controller_get_drvdata(const struct serdev_controller *ctrl) |
146 | { |
147 | return ctrl ? dev_get_drvdata(dev: &ctrl->dev) : NULL; |
148 | } |
149 | |
150 | static inline void serdev_controller_set_drvdata(struct serdev_controller *ctrl, |
151 | void *data) |
152 | { |
153 | dev_set_drvdata(dev: &ctrl->dev, data); |
154 | } |
155 | |
156 | /** |
157 | * serdev_controller_put() - decrement controller refcount |
158 | * @ctrl serdev controller. |
159 | */ |
160 | static inline void serdev_controller_put(struct serdev_controller *ctrl) |
161 | { |
162 | if (ctrl) |
163 | put_device(dev: &ctrl->dev); |
164 | } |
165 | |
166 | struct serdev_device *serdev_device_alloc(struct serdev_controller *); |
167 | int serdev_device_add(struct serdev_device *); |
168 | void serdev_device_remove(struct serdev_device *); |
169 | |
170 | struct serdev_controller *serdev_controller_alloc(struct device *, size_t); |
171 | int serdev_controller_add(struct serdev_controller *); |
172 | void serdev_controller_remove(struct serdev_controller *); |
173 | |
174 | static inline void serdev_controller_write_wakeup(struct serdev_controller *ctrl) |
175 | { |
176 | struct serdev_device *serdev = ctrl->serdev; |
177 | |
178 | if (!serdev || !serdev->ops->write_wakeup) |
179 | return; |
180 | |
181 | serdev->ops->write_wakeup(serdev); |
182 | } |
183 | |
184 | static inline int serdev_controller_receive_buf(struct serdev_controller *ctrl, |
185 | const unsigned char *data, |
186 | size_t count) |
187 | { |
188 | struct serdev_device *serdev = ctrl->serdev; |
189 | |
190 | if (!serdev || !serdev->ops->receive_buf) |
191 | return 0; |
192 | |
193 | return serdev->ops->receive_buf(serdev, data, count); |
194 | } |
195 | |
196 | #if IS_ENABLED(CONFIG_SERIAL_DEV_BUS) |
197 | |
198 | int serdev_device_open(struct serdev_device *); |
199 | void serdev_device_close(struct serdev_device *); |
200 | int devm_serdev_device_open(struct device *, struct serdev_device *); |
201 | unsigned int serdev_device_set_baudrate(struct serdev_device *, unsigned int); |
202 | void serdev_device_set_flow_control(struct serdev_device *, bool); |
203 | int serdev_device_write_buf(struct serdev_device *, const unsigned char *, size_t); |
204 | void serdev_device_wait_until_sent(struct serdev_device *, long); |
205 | int serdev_device_get_tiocm(struct serdev_device *); |
206 | int serdev_device_set_tiocm(struct serdev_device *, int, int); |
207 | int serdev_device_break_ctl(struct serdev_device *serdev, int break_state); |
208 | void serdev_device_write_wakeup(struct serdev_device *); |
209 | int serdev_device_write(struct serdev_device *, const unsigned char *, size_t, long); |
210 | void serdev_device_write_flush(struct serdev_device *); |
211 | int serdev_device_write_room(struct serdev_device *); |
212 | |
213 | /* |
214 | * serdev device driver functions |
215 | */ |
216 | int __serdev_device_driver_register(struct serdev_device_driver *, struct module *); |
217 | #define serdev_device_driver_register(sdrv) \ |
218 | __serdev_device_driver_register(sdrv, THIS_MODULE) |
219 | |
220 | /** |
221 | * serdev_device_driver_unregister() - unregister an serdev client driver |
222 | * @sdrv: the driver to unregister |
223 | */ |
224 | static inline void serdev_device_driver_unregister(struct serdev_device_driver *sdrv) |
225 | { |
226 | if (sdrv) |
227 | driver_unregister(drv: &sdrv->driver); |
228 | } |
229 | |
230 | #define module_serdev_device_driver(__serdev_device_driver) \ |
231 | module_driver(__serdev_device_driver, serdev_device_driver_register, \ |
232 | serdev_device_driver_unregister) |
233 | |
234 | #else |
235 | |
236 | static inline int serdev_device_open(struct serdev_device *sdev) |
237 | { |
238 | return -ENODEV; |
239 | } |
240 | static inline void serdev_device_close(struct serdev_device *sdev) {} |
241 | static inline unsigned int serdev_device_set_baudrate(struct serdev_device *sdev, unsigned int baudrate) |
242 | { |
243 | return 0; |
244 | } |
245 | static inline void serdev_device_set_flow_control(struct serdev_device *sdev, bool enable) {} |
246 | static inline int serdev_device_write_buf(struct serdev_device *serdev, |
247 | const unsigned char *buf, |
248 | size_t count) |
249 | { |
250 | return -ENODEV; |
251 | } |
252 | static inline void serdev_device_wait_until_sent(struct serdev_device *sdev, long timeout) {} |
253 | static inline int serdev_device_get_tiocm(struct serdev_device *serdev) |
254 | { |
255 | return -EOPNOTSUPP; |
256 | } |
257 | static inline int serdev_device_set_tiocm(struct serdev_device *serdev, int set, int clear) |
258 | { |
259 | return -EOPNOTSUPP; |
260 | } |
261 | static inline int serdev_device_break_ctl(struct serdev_device *serdev, int break_state) |
262 | { |
263 | return -EOPNOTSUPP; |
264 | } |
265 | static inline int serdev_device_write(struct serdev_device *sdev, const unsigned char *buf, |
266 | size_t count, unsigned long timeout) |
267 | { |
268 | return -ENODEV; |
269 | } |
270 | static inline void serdev_device_write_flush(struct serdev_device *sdev) {} |
271 | static inline int serdev_device_write_room(struct serdev_device *sdev) |
272 | { |
273 | return 0; |
274 | } |
275 | |
276 | #define serdev_device_driver_register(x) |
277 | #define serdev_device_driver_unregister(x) |
278 | |
279 | #endif /* CONFIG_SERIAL_DEV_BUS */ |
280 | |
281 | static 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 | |
287 | static 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 | |
295 | static 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 | |
303 | int serdev_device_set_parity(struct serdev_device *serdev, |
304 | enum serdev_parity parity); |
305 | |
306 | /* |
307 | * serdev hooks into TTY core |
308 | */ |
309 | struct tty_port; |
310 | struct tty_driver; |
311 | |
312 | #ifdef CONFIG_SERIAL_DEV_CTRL_TTYPORT |
313 | struct device *serdev_tty_port_register(struct tty_port *port, |
314 | struct device *parent, |
315 | struct tty_driver *drv, int idx); |
316 | int serdev_tty_port_unregister(struct tty_port *port); |
317 | #else |
318 | static inline struct device *serdev_tty_port_register(struct tty_port *port, |
319 | struct device *parent, |
320 | struct tty_driver *drv, int idx) |
321 | { |
322 | return ERR_PTR(-ENODEV); |
323 | } |
324 | static inline int serdev_tty_port_unregister(struct tty_port *port) |
325 | { |
326 | return -ENODEV; |
327 | } |
328 | #endif /* CONFIG_SERIAL_DEV_CTRL_TTYPORT */ |
329 | |
330 | struct acpi_resource; |
331 | struct acpi_resource_uart_serialbus; |
332 | |
333 | #ifdef CONFIG_ACPI |
334 | bool serdev_acpi_get_uart_resource(struct acpi_resource *ares, |
335 | struct acpi_resource_uart_serialbus **uart); |
336 | #else |
337 | static inline bool serdev_acpi_get_uart_resource(struct acpi_resource *ares, |
338 | struct acpi_resource_uart_serialbus **uart) |
339 | { |
340 | return false; |
341 | } |
342 | #endif /* CONFIG_ACPI */ |
343 | |
344 | #endif /*_LINUX_SERDEV_H */ |
345 | |