/* * 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 #include #include #include #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 (!IS_ERR_OR_NULL(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; int err; gpios = devm_kzalloc(dev, sizeof(*gpios), GFP_KERNEL); if (!gpios) return ERR_PTR(-ENOMEM); for (i = 0; i < UART_GPIO_MAX; i++) { gpios->gpio[i] = devm_gpiod_get_index(dev, mctrl_gpios_desc[i].name, idx); /* * The GPIOs are maybe not all filled, * this is not an error. */ if (IS_ERR_OR_NULL(gpios->gpio[i])) continue; if (mctrl_gpios_desc[i].dir_out) err = gpiod_direction_output(gpios->gpio[i], 0); else err = gpiod_direction_input(gpios->gpio[i]); if (err) { dev_dbg(dev, "Unable to set direction for %s GPIO", mctrl_gpios_desc[i].name); devm_gpiod_put(dev, gpios->gpio[i]); gpios->gpio[i] = NULL; } } 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 (!IS_ERR_OR_NULL(gpios->gpio[i])) devm_gpiod_put(dev, gpios->gpio[i]); devm_kfree(dev, gpios); } EXPORT_SYMBOL_GPL(mctrl_gpio_free);