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
15 struct uart_port;
16
17 enum 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 */
31 struct mctrl_gpios;
32
33 #ifdef CONFIG_GPIOLIB
34
35 /*
36 * Set state of the modem control output lines via GPIOs.
37 */
38 void 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 */
44 unsigned 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 */
50 unsigned int
51 mctrl_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 */
56 struct 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 call mctrl_gpio_free().
63 * Returns a pointer to the allocated mctrl structure if ok, -ENOMEM on
64 * allocation error.
65 */
66 struct 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 call mctrl_gpio_free().
71 * Returns a pointer to the allocated mctrl structure if ok, -ENOMEM on
72 * allocation error.
73 */
74 struct mctrl_gpios *mctrl_gpio_init_noauto(struct device *dev,
75 unsigned int idx);
76
77 /*
78 * Free the mctrl_gpios structure.
79 * Normally, this function will not be called, as the GPIOs will
80 * be disposed of by the resource management code.
81 */
82 void mctrl_gpio_free(struct device *dev, struct mctrl_gpios *gpios);
83
84 /*
85 * Enable gpio interrupts to report status line changes.
86 */
87 void mctrl_gpio_enable_ms(struct mctrl_gpios *gpios);
88
89 /*
90 * Disable gpio interrupts to report status line changes.
91 */
92 void mctrl_gpio_disable_ms(struct mctrl_gpios *gpios);
93
94 /*
95 * Enable gpio wakeup interrupts to enable wake up source.
96 */
97 void mctrl_gpio_enable_irq_wake(struct mctrl_gpios *gpios);
98
99 /*
100 * Disable gpio wakeup interrupts to enable wake up source.
101 */
102 void mctrl_gpio_disable_irq_wake(struct mctrl_gpios *gpios);
103
104 #else /* GPIOLIB */
105
106 static inline
mctrl_gpio_set(struct mctrl_gpios * gpios,unsigned int mctrl)107 void mctrl_gpio_set(struct mctrl_gpios *gpios, unsigned int mctrl)
108 {
109 }
110
111 static inline
mctrl_gpio_get(struct mctrl_gpios * gpios,unsigned int * mctrl)112 unsigned int mctrl_gpio_get(struct mctrl_gpios *gpios, unsigned int *mctrl)
113 {
114 return *mctrl;
115 }
116
117 static inline unsigned int
mctrl_gpio_get_outputs(struct mctrl_gpios * gpios,unsigned int * mctrl)118 mctrl_gpio_get_outputs(struct mctrl_gpios *gpios, unsigned int *mctrl)
119 {
120 return *mctrl;
121 }
122
123 static inline
mctrl_gpio_to_gpiod(struct mctrl_gpios * gpios,enum mctrl_gpio_idx gidx)124 struct gpio_desc *mctrl_gpio_to_gpiod(struct mctrl_gpios *gpios,
125 enum mctrl_gpio_idx gidx)
126 {
127 return NULL;
128 }
129
130 static inline
mctrl_gpio_init(struct uart_port * port,unsigned int idx)131 struct mctrl_gpios *mctrl_gpio_init(struct uart_port *port, unsigned int idx)
132 {
133 return NULL;
134 }
135
136 static inline
mctrl_gpio_init_noauto(struct device * dev,unsigned int idx)137 struct mctrl_gpios *mctrl_gpio_init_noauto(struct device *dev, unsigned int idx)
138 {
139 return NULL;
140 }
141
142 static inline
mctrl_gpio_free(struct device * dev,struct mctrl_gpios * gpios)143 void mctrl_gpio_free(struct device *dev, struct mctrl_gpios *gpios)
144 {
145 }
146
mctrl_gpio_enable_ms(struct mctrl_gpios * gpios)147 static inline void mctrl_gpio_enable_ms(struct mctrl_gpios *gpios)
148 {
149 }
150
mctrl_gpio_disable_ms(struct mctrl_gpios * gpios)151 static inline void mctrl_gpio_disable_ms(struct mctrl_gpios *gpios)
152 {
153 }
154
mctrl_gpio_enable_irq_wake(struct mctrl_gpios * gpios)155 static inline void mctrl_gpio_enable_irq_wake(struct mctrl_gpios *gpios)
156 {
157 }
158
mctrl_gpio_disable_irq_wake(struct mctrl_gpios * gpios)159 static inline void mctrl_gpio_disable_irq_wake(struct mctrl_gpios *gpios)
160 {
161 }
162
163 #endif /* GPIOLIB */
164
165 #endif
166
