/*
* Helpers for controlling modem lines via GPIO
*
* Copyright (C) 2014 Paratronic S.A.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
*/
#ifndef __SERIAL_MCTRL_GPIO__
#define __SERIAL_MCTRL_GPIO__
#include <linux/err.h>
#include <linux/device.h>
#include <linux/gpio/consumer.h>
enum mctrl_gpio_idx {
UART_GPIO_CTS,
UART_GPIO_DSR,
UART_GPIO_DCD,
UART_GPIO_RNG,
UART_GPIO_RI = UART_GPIO_RNG,
UART_GPIO_RTS,
UART_GPIO_DTR,
UART_GPIO_OUT1,
UART_GPIO_OUT2,
UART_GPIO_MAX,
};
/*
* Opaque descriptor for modem lines controlled by GPIOs
*/
struct mctrl_gpios;
#ifdef CONFIG_GPIOLIB
/*
* Set state of the modem control output lines via GPIOs.
*/
void mctrl_gpio_set(struct mctrl_gpios *gpios, unsigned int mctrl);
/*
* Get state of the modem control output lines from GPIOs.
* The mctrl flags are updated and returned.
*/
unsigned int mctrl_gpio_get(struct mctrl_gpios *gpios, unsigned int *mctrl);
/*
* Returns the associated struct gpio_desc to the modem line gidx
*/
struct gpio_desc *mctrl_gpio_to_gpiod(struct mctrl_gpios *gpios,
enum mctrl_gpio_idx gidx);
/*
* Request and set direction of modem control lines GPIOs.
* devm_* functions are used, so there's no need to call mctrl_gpio_free().
* Returns a pointer to the allocated mctrl structure if ok, -ENOMEM on
* allocation error.
*/
struct mctrl_gpios *mctrl_gpio_init(struct device *dev, unsigned int idx);
/*
* Free the mctrl_gpios structure.
* Normally, this function will not be called, as the GPIOs will
* be disposed of by the resource management code.
*/
void mctrl_gpio_free(struct device *dev, struct mctrl_gpios *gpios);
#else /* GPIOLIB */
static inline
void mctrl_gpio_set(struct mctrl_gpios *gpios, unsigned int mctrl)
{
}
static inline
unsigned int mctrl_gpio_get(struct mctrl_gpios *gpios, unsigned int *mctrl)
{
return *mctrl;
}
static inline
struct gpio_desc *mctrl_gpio_to_gpiod(struct mctrl_gpios *gpios,
enum mctrl_gpio_idx gidx)
{
return ERR_PTR(-ENOSYS);
}
static inline
struct mctrl_gpios *mctrl_gpio_init(struct device *dev, unsigned int idx)
{
return ERR_PTR(-ENOSYS);
}
static inline
void mctrl_gpio_free(struct device *dev, struct mctrl_gpios *gpios)
{
}
#endif /* GPIOLIB */
#endif
