| b.liu | e958203 | 2025-04-17 19:18:16 +0800 | [diff] [blame^] | 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 | #else /* GPIOLIB */ |
| 95 | |
| 96 | static inline |
| 97 | void mctrl_gpio_set(struct mctrl_gpios *gpios, unsigned int mctrl) |
| 98 | { |
| 99 | } |
| 100 | |
| 101 | static inline |
| 102 | unsigned int mctrl_gpio_get(struct mctrl_gpios *gpios, unsigned int *mctrl) |
| 103 | { |
| 104 | return *mctrl; |
| 105 | } |
| 106 | |
| 107 | static inline unsigned int |
| 108 | mctrl_gpio_get_outputs(struct mctrl_gpios *gpios, unsigned int *mctrl) |
| 109 | { |
| 110 | return *mctrl; |
| 111 | } |
| 112 | |
| 113 | static inline |
| 114 | struct gpio_desc *mctrl_gpio_to_gpiod(struct mctrl_gpios *gpios, |
| 115 | enum mctrl_gpio_idx gidx) |
| 116 | { |
| 117 | return NULL; |
| 118 | } |
| 119 | |
| 120 | static inline |
| 121 | struct mctrl_gpios *mctrl_gpio_init(struct uart_port *port, unsigned int idx) |
| 122 | { |
| 123 | return NULL; |
| 124 | } |
| 125 | |
| 126 | static inline |
| 127 | struct mctrl_gpios *mctrl_gpio_init_noauto(struct device *dev, unsigned int idx) |
| 128 | { |
| 129 | return NULL; |
| 130 | } |
| 131 | |
| 132 | static inline |
| 133 | void mctrl_gpio_free(struct device *dev, struct mctrl_gpios *gpios) |
| 134 | { |
| 135 | } |
| 136 | |
| 137 | static inline void mctrl_gpio_enable_ms(struct mctrl_gpios *gpios) |
| 138 | { |
| 139 | } |
| 140 | |
| 141 | static inline void mctrl_gpio_disable_ms(struct mctrl_gpios *gpios) |
| 142 | { |
| 143 | } |
| 144 | |
| 145 | #endif /* GPIOLIB */ |
| 146 | |
| 147 | #endif |