1/* SPDX-License-Identifier: GPL-2.0+ */
2/*
3 * Helpers for controlling modem lines via GPIO
4 *
5 * Copyright (C) 2014 Paratronic S.A.
6 */
7
8#ifndef __SERIAL_MCTRL_GPIO__
9#define __SERIAL_MCTRL_GPIO__
10
11#include <linux/err.h>
12#include <linux/device.h>
13#include <linux/gpio/consumer.h>
14
15struct uart_port;
16
17enum mctrl_gpio_idx {
18 UART_GPIO_CTS,
19 UART_GPIO_DSR,
20 UART_GPIO_DCD,
21 UART_GPIO_RNG,
22 UART_GPIO_RI = UART_GPIO_RNG,
23 UART_GPIO_RTS,
24 UART_GPIO_DTR,
25 UART_GPIO_MAX,
26};
27
28/*
29 * Opaque descriptor for modem lines controlled by GPIOs
30 */
31struct mctrl_gpios;
32
33#ifdef CONFIG_GPIOLIB
34
35/*
36 * Set state of the modem control output lines via GPIOs.
37 */
38void mctrl_gpio_set(struct mctrl_gpios *gpios, unsigned int mctrl);
39
40/*
41 * Get state of the modem control input lines from GPIOs.
42 * The mctrl flags are updated and returned.
43 */
44unsigned int mctrl_gpio_get(struct mctrl_gpios *gpios, unsigned int *mctrl);
45
46/*
47 * Get state of the modem control output lines from GPIOs.
48 * The mctrl flags are updated and returned.
49 */
50unsigned int
51mctrl_gpio_get_outputs(struct mctrl_gpios *gpios, unsigned int *mctrl);
52
53/*
54 * Returns the associated struct gpio_desc to the modem line gidx
55 */
56struct gpio_desc *mctrl_gpio_to_gpiod(struct mctrl_gpios *gpios,
57 enum mctrl_gpio_idx gidx);
58
59/*
60 * Request and set direction of modem control line GPIOs and set up irq
61 * handling.
62 * devm_* functions are used, so there's no need to explicitly free.
63 * Returns a pointer to the allocated mctrl structure if ok, -ENOMEM on
64 * allocation error.
65 */
66struct mctrl_gpios *mctrl_gpio_init(struct uart_port *port, unsigned int idx);
67
68/*
69 * Request and set direction of modem control line GPIOs.
70 * devm_* functions are used, so there's no need to explicitly free.
71 * Returns a pointer to the allocated mctrl structure if ok, -ENOMEM on
72 * allocation error.
73 */
74struct mctrl_gpios *mctrl_gpio_init_noauto(struct device *dev,
75 unsigned int idx);
76
77/*
78 * Enable gpio interrupts to report status line changes.
79 */
80void mctrl_gpio_enable_ms(struct mctrl_gpios *gpios);
81
82/*
83 * Disable gpio interrupts to report status line changes, and block until
84 * any corresponding IRQ is processed
85 */
86void mctrl_gpio_disable_ms_sync(struct mctrl_gpios *gpios);
87
88/*
89 * Disable gpio interrupts to report status line changes, and return
90 * immediately
91 */
92void mctrl_gpio_disable_ms_no_sync(struct mctrl_gpios *gpios);
93
94/*
95 * Enable gpio wakeup interrupts to enable wake up source.
96 */
97void mctrl_gpio_enable_irq_wake(struct mctrl_gpios *gpios);
98
99/*
100 * Disable gpio wakeup interrupts to enable wake up source.
101 */
102void mctrl_gpio_disable_irq_wake(struct mctrl_gpios *gpios);
103
104#else /* GPIOLIB */
105
106static inline
107void mctrl_gpio_set(struct mctrl_gpios *gpios, unsigned int mctrl)
108{
109}
110
111static inline
112unsigned int mctrl_gpio_get(struct mctrl_gpios *gpios, unsigned int *mctrl)
113{
114 return *mctrl;
115}
116
117static inline unsigned int
118mctrl_gpio_get_outputs(struct mctrl_gpios *gpios, unsigned int *mctrl)
119{
120 return *mctrl;
121}
122
123static inline
124struct gpio_desc *mctrl_gpio_to_gpiod(struct mctrl_gpios *gpios,
125 enum mctrl_gpio_idx gidx)
126{
127 return NULL;
128}
129
130static inline
131struct mctrl_gpios *mctrl_gpio_init(struct uart_port *port, unsigned int idx)
132{
133 return NULL;
134}
135
136static inline
137struct mctrl_gpios *mctrl_gpio_init_noauto(struct device *dev, unsigned int idx)
138{
139 return NULL;
140}
141
142static inline void mctrl_gpio_enable_ms(struct mctrl_gpios *gpios)
143{
144}
145
146static inline void mctrl_gpio_disable_ms_sync(struct mctrl_gpios *gpios)
147{
148}
149
150static inline void mctrl_gpio_disable_ms_no_sync(struct mctrl_gpios *gpios)
151{
152}
153
154static inline void mctrl_gpio_enable_irq_wake(struct mctrl_gpios *gpios)
155{
156}
157
158static inline void mctrl_gpio_disable_irq_wake(struct mctrl_gpios *gpios)
159{
160}
161
162#endif /* GPIOLIB */
163
164#endif
165