linux/drivers/tty/serial/serial_mctrl_gpio.c
Uwe Kleine-König 445df7ff3f serial: mctrl-gpio: drop usages of IS_ERR_OR_NULL
The function mctrl_gpio_init returns failure if the assignment to any
member of the gpio array results in an error pointer.  So there is no
need to check for such error values in the other functions.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-24 13:06:08 -07:00

125 lines
3.0 KiB
C

/*
* 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.
*
*/
#include <linux/err.h>
#include <linux/device.h>
#include <linux/gpio/consumer.h>
#include <linux/termios.h>
#include "serial_mctrl_gpio.h"
struct mctrl_gpios {
struct gpio_desc *gpio[UART_GPIO_MAX];
};
static const struct {
const char *name;
unsigned int mctrl;
bool dir_out;
} mctrl_gpios_desc[UART_GPIO_MAX] = {
{ "cts", TIOCM_CTS, false, },
{ "dsr", TIOCM_DSR, false, },
{ "dcd", TIOCM_CD, false, },
{ "rng", TIOCM_RNG, false, },
{ "rts", TIOCM_RTS, true, },
{ "dtr", TIOCM_DTR, true, },
{ "out1", TIOCM_OUT1, true, },
{ "out2", TIOCM_OUT2, true, },
};
void mctrl_gpio_set(struct mctrl_gpios *gpios, unsigned int mctrl)
{
enum mctrl_gpio_idx i;
struct gpio_desc *desc_array[UART_GPIO_MAX];
int value_array[UART_GPIO_MAX];
unsigned int count = 0;
for (i = 0; i < UART_GPIO_MAX; i++)
if (gpios->gpio[i] && mctrl_gpios_desc[i].dir_out) {
desc_array[count] = gpios->gpio[i];
value_array[count] = !!(mctrl & mctrl_gpios_desc[i].mctrl);
count++;
}
gpiod_set_array(count, desc_array, value_array);
}
EXPORT_SYMBOL_GPL(mctrl_gpio_set);
struct gpio_desc *mctrl_gpio_to_gpiod(struct mctrl_gpios *gpios,
enum mctrl_gpio_idx gidx)
{
return gpios->gpio[gidx];
}
EXPORT_SYMBOL_GPL(mctrl_gpio_to_gpiod);
unsigned int mctrl_gpio_get(struct mctrl_gpios *gpios, unsigned int *mctrl)
{
enum mctrl_gpio_idx i;
for (i = 0; i < UART_GPIO_MAX; i++) {
if (gpios->gpio[i] && !mctrl_gpios_desc[i].dir_out) {
if (gpiod_get_value(gpios->gpio[i]))
*mctrl |= mctrl_gpios_desc[i].mctrl;
else
*mctrl &= ~mctrl_gpios_desc[i].mctrl;
}
}
return *mctrl;
}
EXPORT_SYMBOL_GPL(mctrl_gpio_get);
struct mctrl_gpios *mctrl_gpio_init(struct device *dev, unsigned int idx)
{
struct mctrl_gpios *gpios;
enum mctrl_gpio_idx i;
gpios = devm_kzalloc(dev, sizeof(*gpios), GFP_KERNEL);
if (!gpios)
return ERR_PTR(-ENOMEM);
for (i = 0; i < UART_GPIO_MAX; i++) {
enum gpiod_flags flags;
if (mctrl_gpios_desc[i].dir_out)
flags = GPIOD_OUT_LOW;
else
flags = GPIOD_IN;
gpios->gpio[i] =
devm_gpiod_get_index_optional(dev,
mctrl_gpios_desc[i].name,
idx, flags);
if (IS_ERR(gpios->gpio[i]))
return ERR_CAST(gpios->gpio[i]);
}
return gpios;
}
EXPORT_SYMBOL_GPL(mctrl_gpio_init);
void mctrl_gpio_free(struct device *dev, struct mctrl_gpios *gpios)
{
enum mctrl_gpio_idx i;
for (i = 0; i < UART_GPIO_MAX; i++)
if (gpios->gpio[i])
devm_gpiod_put(dev, gpios->gpio[i]);
devm_kfree(dev, gpios);
}
EXPORT_SYMBOL_GPL(mctrl_gpio_free);