tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Helpers for controlling modem lines via GPIO
3 *
4 * Copyright (C) 2014 Paratronic S.A.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 */
17
18#ifndef __SERIAL_MCTRL_GPIO__
19#define __SERIAL_MCTRL_GPIO__
20
21#include <linux/err.h>
22#include <linux/device.h>
23#include <linux/gpio/consumer.h>
24
25struct uart_port;
26
27enum mctrl_gpio_idx {
28 UART_GPIO_CTS,
29 UART_GPIO_DSR,
30 UART_GPIO_DCD,
31 UART_GPIO_RNG,
32 UART_GPIO_RI = UART_GPIO_RNG,
33 UART_GPIO_RTS,
34 UART_GPIO_DTR,
35 UART_GPIO_MAX,
36};
37
38/*
39 * Opaque descriptor for modem lines controlled by GPIOs
40 */
41struct mctrl_gpios;
42
43#ifdef CONFIG_GPIOLIB
44
45/*
46 * Set state of the modem control output lines via GPIOs.
47 */
48void mctrl_gpio_set(struct mctrl_gpios *gpios, unsigned int mctrl);
49
50/*
51 * Get state of the modem control input lines from GPIOs.
52 * The mctrl flags are updated and returned.
53 */
54unsigned int mctrl_gpio_get(struct mctrl_gpios *gpios, unsigned int *mctrl);
55
56/*
57 * Get state of the modem control output lines from GPIOs.
58 * The mctrl flags are updated and returned.
59 */
60unsigned int
61mctrl_gpio_get_outputs(struct mctrl_gpios *gpios, unsigned int *mctrl);
62
63/*
64 * Returns the associated struct gpio_desc to the modem line gidx
65 */
66struct gpio_desc *mctrl_gpio_to_gpiod(struct mctrl_gpios *gpios,
67 enum mctrl_gpio_idx gidx);
68
69/*
70 * Request and set direction of modem control line GPIOs and set up irq
71 * handling.
72 * devm_* functions are used, so there's no need to call mctrl_gpio_free().
73 * Returns a pointer to the allocated mctrl structure if ok, -ENOMEM on
74 * allocation error.
75 */
76struct mctrl_gpios *mctrl_gpio_init(struct uart_port *port, unsigned int idx);
77
78/*
79 * Request and set direction of modem control line GPIOs.
80 * devm_* functions are used, so there's no need to call mctrl_gpio_free().
81 * Returns a pointer to the allocated mctrl structure if ok, -ENOMEM on
82 * allocation error.
83 */
84struct mctrl_gpios *mctrl_gpio_init_noauto(struct device *dev,
85 unsigned int idx);
86
87/*
88 * Free the mctrl_gpios structure.
89 * Normally, this function will not be called, as the GPIOs will
90 * be disposed of by the resource management code.
91 */
92void mctrl_gpio_free(struct device *dev, struct mctrl_gpios *gpios);
93
94/*
95 * Enable gpio interrupts to report status line changes.
96 */
97void mctrl_gpio_enable_ms(struct mctrl_gpios *gpios);
98
99/*
100 * Disable gpio interrupts to report status line changes.
101 */
102void mctrl_gpio_disable_ms(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 ERR_PTR(-ENOSYS);
128}
129
130static inline
131struct mctrl_gpios *mctrl_gpio_init(struct uart_port *port, unsigned int idx)
132{
133 return ERR_PTR(-ENOSYS);
134}
135
136static inline
137struct mctrl_gpios *mctrl_gpio_init_noauto(struct device *dev, unsigned int idx)
138{
139 return ERR_PTR(-ENOSYS);
140}
141
142static inline
143void mctrl_gpio_free(struct device *dev, struct mctrl_gpios *gpios)
144{
145}
146
147static inline void mctrl_gpio_enable_ms(struct mctrl_gpios *gpios)
148{
149}
150
151static inline void mctrl_gpio_disable_ms(struct mctrl_gpios *gpios)
152{
153}
154
155#endif /* GPIOLIB */
156
157#endif