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_OUT1,
36 UART_GPIO_OUT2,
37 UART_GPIO_MAX,
38};
39
40/*
41 * Opaque descriptor for modem lines controlled by GPIOs
42 */
43struct mctrl_gpios;
44
45#ifdef CONFIG_GPIOLIB
46
47/*
48 * Set state of the modem control output lines via GPIOs.
49 */
50void mctrl_gpio_set(struct mctrl_gpios *gpios, unsigned int mctrl);
51
52/*
53 * Get state of the modem control output lines from GPIOs.
54 * The mctrl flags are updated and returned.
55 */
56unsigned int mctrl_gpio_get(struct mctrl_gpios *gpios, unsigned int *mctrl);
57
58/*
59 * Returns the associated struct gpio_desc to the modem line gidx
60 */
61struct gpio_desc *mctrl_gpio_to_gpiod(struct mctrl_gpios *gpios,
62 enum mctrl_gpio_idx gidx);
63
64/*
65 * Request and set direction of modem control lines GPIOs and sets up irq
66 * handling.
67 * devm_* functions are used, so there's no need to call mctrl_gpio_free().
68 * Returns a pointer to the allocated mctrl structure if ok, -ENOMEM on
69 * allocation error.
70 */
71struct mctrl_gpios *mctrl_gpio_init(struct uart_port *port, unsigned int idx);
72
73/*
74 * Request and set direction of modem control lines GPIOs.
75 * devm_* functions are used, so there's no need to call mctrl_gpio_free().
76 * Returns a pointer to the allocated mctrl structure if ok, -ENOMEM on
77 * allocation error.
78 */
79struct mctrl_gpios *mctrl_gpio_init_noauto(struct device *dev,
80 unsigned int idx);
81
82/*
83 * Free the mctrl_gpios structure.
84 * Normally, this function will not be called, as the GPIOs will
85 * be disposed of by the resource management code.
86 */
87void mctrl_gpio_free(struct device *dev, struct mctrl_gpios *gpios);
88
89/*
90 * Enable gpio interrupts to report status line changes.
91 */
92void mctrl_gpio_enable_ms(struct mctrl_gpios *gpios);
93
94/*
95 * Disable gpio interrupts to report status line changes.
96 */
97void mctrl_gpio_disable_ms(struct mctrl_gpios *gpios);
98
99#else /* GPIOLIB */
100
101static inline
102void mctrl_gpio_set(struct mctrl_gpios *gpios, unsigned int mctrl)
103{
104}
105
106static inline
107unsigned int mctrl_gpio_get(struct mctrl_gpios *gpios, unsigned int *mctrl)
108{
109 return *mctrl;
110}
111
112static inline
113struct gpio_desc *mctrl_gpio_to_gpiod(struct mctrl_gpios *gpios,
114 enum mctrl_gpio_idx gidx)
115{
116 return ERR_PTR(-ENOSYS);
117}
118
119static inline
120struct mctrl_gpios *mctrl_gpio_init(struct uart_port *port, unsigned int idx)
121{
122 return ERR_PTR(-ENOSYS);
123}
124
125static inline
126struct mctrl_gpios *mctrl_gpio_init_noauto(struct device *dev, unsigned int idx)
127{
128 return ERR_PTR(-ENOSYS);
129}
130
131static inline
132void mctrl_gpio_free(struct device *dev, struct mctrl_gpios *gpios)
133{
134}
135
136static inline void mctrl_gpio_enable_ms(struct mctrl_gpios *gpios)
137{
138}
139
140static inline void mctrl_gpio_disable_ms(struct mctrl_gpios *gpios)
141{
142}
143
144#endif /* GPIOLIB */
145
146#endif