drivers/tty/serial/serial_mctrl_gpio.c - third_party/kernel - Git at Google

 // SPDX-License-Identifier: GPL-2.0+
 /*
  * Helpers for controlling modem lines via GPIO
  *
  * Copyright (C) 2014 Paratronic S.A.
  */

 #include <linux/err.h>
 #include <linux/device.h>
 #include <linux/irq.h>
 #include <linux/gpio/consumer.h>
 #include <linux/termios.h>
 #include <linux/serial_core.h>
 #include <linux/module.h>
 #include <linux/property.h>

 #include "serial_mctrl_gpio.h"

 struct mctrl_gpios {
 	struct uart_port *port;
 	struct gpio_desc *gpio[UART_GPIO_MAX];
 	int irq[UART_GPIO_MAX];
 	unsigned int mctrl_prev;
 	bool mctrl_on;
 };

 static const struct {
 	const char *name;
 	unsigned int mctrl;
 	enum gpiod_flags flags;
 } mctrl_gpios_desc[UART_GPIO_MAX] = {
 	{ "cts", TIOCM_CTS, GPIOD_IN, },
 	{ "dsr", TIOCM_DSR, GPIOD_IN, },
 	{ "dcd", TIOCM_CD,  GPIOD_IN, },
 	{ "rng", TIOCM_RNG, GPIOD_IN, },
 	{ "rts", TIOCM_RTS, GPIOD_OUT_LOW, },
 	{ "dtr", TIOCM_DTR, GPIOD_OUT_LOW, },
 };

 static bool mctrl_gpio_flags_is_dir_out(unsigned int idx)
 {
 	return mctrl_gpios_desc[idx].flags & GPIOD_FLAGS_BIT_DIR_OUT;
 }

 /**
  * mctrl_gpio_set - set gpios according to mctrl state
  * @gpios: gpios to set
  * @mctrl: state to set
  *
  * Set the gpios according to the mctrl state.
  */
 void mctrl_gpio_set(struct mctrl_gpios *gpios, unsigned int mctrl)
 {
 	enum mctrl_gpio_idx i;
 	struct gpio_desc *desc_array[UART_GPIO_MAX];
 	DECLARE_BITMAP(values, UART_GPIO_MAX);
 	unsigned int count = 0;

 	if (gpios == NULL)
 		return;

 	for (i = 0; i < UART_GPIO_MAX; i++)
 		if (gpios->gpio[i] && mctrl_gpio_flags_is_dir_out(i)) {
 			desc_array[count] = gpios->gpio[i];
 			__assign_bit(count, values,
 				     mctrl & mctrl_gpios_desc[i].mctrl);
 			count++;
 		}
 	gpiod_set_array_value(count, desc_array, NULL, values);
 }
 EXPORT_SYMBOL_GPL(mctrl_gpio_set);

 /**
  * mctrl_gpio_to_gpiod - obtain gpio_desc of modem line index
  * @gpios: gpios to look into
  * @gidx: index of the modem line
  * Returns: the gpio_desc structure associated to the modem line index
  */
 struct gpio_desc *mctrl_gpio_to_gpiod(struct mctrl_gpios *gpios,
 				      enum mctrl_gpio_idx gidx)
 {
 	if (gpios == NULL)
 		return NULL;

 	return gpios->gpio[gidx];
 }
 EXPORT_SYMBOL_GPL(mctrl_gpio_to_gpiod);

 /**
  * mctrl_gpio_get - update mctrl with the gpios values.
  * @gpios: gpios to get the info from
  * @mctrl: mctrl to set
  * Returns: modified mctrl (the same value as in @mctrl)
  *
  * Update mctrl with the gpios values.
  */
 unsigned int mctrl_gpio_get(struct mctrl_gpios *gpios, unsigned int *mctrl)
 {
 	enum mctrl_gpio_idx i;

 	if (gpios == NULL)
 		return *mctrl;

 	for (i = 0; i < UART_GPIO_MAX; i++) {
 		if (gpios->gpio[i] && !mctrl_gpio_flags_is_dir_out(i)) {
 			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);

 unsigned int
 mctrl_gpio_get_outputs(struct mctrl_gpios *gpios, unsigned int *mctrl)
 {
 	enum mctrl_gpio_idx i;

 	if (gpios == NULL)
 		return *mctrl;

 	for (i = 0; i < UART_GPIO_MAX; i++) {
 		if (gpios->gpio[i] && mctrl_gpio_flags_is_dir_out(i)) {
 			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_outputs);

 struct mctrl_gpios *mctrl_gpio_init_noauto(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++) {
 		char *gpio_str;
 		bool present;

 		/* Check if GPIO property exists and continue if not */
 		gpio_str = kasprintf(GFP_KERNEL, "%s-gpios",
 				     mctrl_gpios_desc[i].name);
 		if (!gpio_str)
 			continue;

 		present = device_property_present(dev, gpio_str);
 		kfree(gpio_str);
 		if (!present)
 			continue;

 		gpios->gpio[i] =
 			devm_gpiod_get_index_optional(dev,
 						      mctrl_gpios_desc[i].name,
 						      idx,
 						      mctrl_gpios_desc[i].flags);

 		if (IS_ERR(gpios->gpio[i]))
 			return ERR_CAST(gpios->gpio[i]);
 	}

 	return gpios;
 }
 EXPORT_SYMBOL_GPL(mctrl_gpio_init_noauto);

 #define MCTRL_ANY_DELTA (TIOCM_RI | TIOCM_DSR | TIOCM_CD | TIOCM_CTS)
 static irqreturn_t mctrl_gpio_irq_handle(int irq, void *context)
 {
 	struct mctrl_gpios *gpios = context;
 	struct uart_port *port = gpios->port;
 	u32 mctrl = gpios->mctrl_prev;
 	u32 mctrl_diff;
 	unsigned long flags;

 	mctrl_gpio_get(gpios, &mctrl);

 	uart_port_lock_irqsave(port, &flags);

 	mctrl_diff = mctrl ^ gpios->mctrl_prev;
 	gpios->mctrl_prev = mctrl;

 	if (mctrl_diff & MCTRL_ANY_DELTA && port->state != NULL) {
 		if ((mctrl_diff & mctrl) & TIOCM_RI)
 			port->icount.rng++;

 		if ((mctrl_diff & mctrl) & TIOCM_DSR)
 			port->icount.dsr++;

 		if (mctrl_diff & TIOCM_CD)
 			uart_handle_dcd_change(port, mctrl & TIOCM_CD);

 		if (mctrl_diff & TIOCM_CTS)
 			uart_handle_cts_change(port, mctrl & TIOCM_CTS);

 		wake_up_interruptible(&port->state->port.delta_msr_wait);
 	}

 	uart_port_unlock_irqrestore(port, flags);

 	return IRQ_HANDLED;
 }

 /**
  * mctrl_gpio_init - initialize uart gpios
  * @port: port to initialize gpios for
  * @idx: index of the gpio in the @port's device
  *
  * This will get the {cts,rts,...}-gpios from device tree if they are present
  * and request them, set direction etc, and return an allocated structure.
  * `devm_*` functions are used, so there's no need to call mctrl_gpio_free().
  * As this sets up the irq handling, make sure to not handle changes to the
  * gpio input lines in your driver, too.
  */
 struct mctrl_gpios *mctrl_gpio_init(struct uart_port *port, unsigned int idx)
 {
 	struct mctrl_gpios *gpios;
 	enum mctrl_gpio_idx i;

 	gpios = mctrl_gpio_init_noauto(port->dev, idx);
 	if (IS_ERR(gpios))
 		return gpios;

 	gpios->port = port;

 	for (i = 0; i < UART_GPIO_MAX; ++i) {
 		int ret;

 		if (!gpios->gpio[i] || mctrl_gpio_flags_is_dir_out(i))
 			continue;

 		ret = gpiod_to_irq(gpios->gpio[i]);
 		if (ret < 0) {
 			dev_err(port->dev,
 				"failed to find corresponding irq for %s (idx=%d, err=%d)\n",
 				mctrl_gpios_desc[i].name, idx, ret);
 			return ERR_PTR(ret);
 		}
 		gpios->irq[i] = ret;

 		/* irqs should only be enabled in .enable_ms */
 		irq_set_status_flags(gpios->irq[i], IRQ_NOAUTOEN);

 		ret = devm_request_irq(port->dev, gpios->irq[i],
 				       mctrl_gpio_irq_handle,
 				       IRQ_TYPE_EDGE_BOTH, dev_name(port->dev),
 				       gpios);
 		if (ret) {
 			/* alternatively implement polling */
 			dev_err(port->dev,
 				"failed to request irq for %s (idx=%d, err=%d)\n",
 				mctrl_gpios_desc[i].name, idx, ret);
 			return ERR_PTR(ret);
 		}
 	}

 	return gpios;
 }
 EXPORT_SYMBOL_GPL(mctrl_gpio_init);

 /**
  * mctrl_gpio_free - explicitly free uart gpios
  * @dev: uart port's device
  * @gpios: gpios structure to be freed
  *
  * This will free the requested gpios in mctrl_gpio_init(). As `devm_*`
  * functions are used, there's generally no need to call this function.
  */
 void mctrl_gpio_free(struct device *dev, struct mctrl_gpios *gpios)
 {
 	enum mctrl_gpio_idx i;

 	if (gpios == NULL)
 		return;

 	for (i = 0; i < UART_GPIO_MAX; i++) {
 		if (gpios->irq[i])
 			devm_free_irq(gpios->port->dev, gpios->irq[i], gpios);

 		if (gpios->gpio[i])
 			devm_gpiod_put(dev, gpios->gpio[i]);
 	}
 	devm_kfree(dev, gpios);
 }
 EXPORT_SYMBOL_GPL(mctrl_gpio_free);

 /**
  * mctrl_gpio_enable_ms - enable irqs and handling of changes to the ms lines
  * @gpios: gpios to enable
  */
 void mctrl_gpio_enable_ms(struct mctrl_gpios *gpios)
 {
 	enum mctrl_gpio_idx i;

 	if (gpios == NULL)
 		return;

 	/* .enable_ms may be called multiple times */
 	if (gpios->mctrl_on)
 		return;

 	gpios->mctrl_on = true;

 	/* get initial status of modem lines GPIOs */
 	mctrl_gpio_get(gpios, &gpios->mctrl_prev);

 	for (i = 0; i < UART_GPIO_MAX; ++i) {
 		if (!gpios->irq[i])
 			continue;

 		enable_irq(gpios->irq[i]);
 	}
 }
 EXPORT_SYMBOL_GPL(mctrl_gpio_enable_ms);

 static void mctrl_gpio_disable_ms(struct mctrl_gpios *gpios, bool sync)
 {
 	enum mctrl_gpio_idx i;

 	if (gpios == NULL)
 		return;

 	if (!gpios->mctrl_on)
 		return;

 	gpios->mctrl_on = false;

 	for (i = 0; i < UART_GPIO_MAX; ++i) {
 		if (!gpios->irq[i])
 			continue;

 		if (sync)
 			disable_irq(gpios->irq[i]);
 		else
 			disable_irq_nosync(gpios->irq[i]);
 	}
 }

 /**
  * mctrl_gpio_disable_ms_sync - disable irqs and handling of changes to the ms
  * lines, and wait for any pending IRQ to be processed
  * @gpios: gpios to disable
  */
 void mctrl_gpio_disable_ms_sync(struct mctrl_gpios *gpios)
 {
 	mctrl_gpio_disable_ms(gpios, true);
 }
 EXPORT_SYMBOL_GPL(mctrl_gpio_disable_ms_sync);

 /**
  * mctrl_gpio_disable_ms_no_sync - disable irqs and handling of changes to the
  * ms lines, and return immediately
  * @gpios: gpios to disable
  */
 void mctrl_gpio_disable_ms_no_sync(struct mctrl_gpios *gpios)
 {
 	mctrl_gpio_disable_ms(gpios, false);
 }
 EXPORT_SYMBOL_GPL(mctrl_gpio_disable_ms_no_sync);

 void mctrl_gpio_enable_irq_wake(struct mctrl_gpios *gpios)
 {
 	enum mctrl_gpio_idx i;

 	if (!gpios)
 		return;

 	if (!gpios->mctrl_on)
 		return;

 	for (i = 0; i < UART_GPIO_MAX; ++i) {
 		if (!gpios->irq[i])
 			continue;

 		enable_irq_wake(gpios->irq[i]);
 	}
 }
 EXPORT_SYMBOL_GPL(mctrl_gpio_enable_irq_wake);

 void mctrl_gpio_disable_irq_wake(struct mctrl_gpios *gpios)
 {
 	enum mctrl_gpio_idx i;

 	if (!gpios)
 		return;

 	if (!gpios->mctrl_on)
 		return;

 	for (i = 0; i < UART_GPIO_MAX; ++i) {
 		if (!gpios->irq[i])
 			continue;

 		disable_irq_wake(gpios->irq[i]);
 	}
 }
 EXPORT_SYMBOL_GPL(mctrl_gpio_disable_irq_wake);

 MODULE_DESCRIPTION("Helpers for controlling modem lines via GPIO");
 MODULE_LICENSE("GPL");
	// SPDX-License-Identifier: GPL-2.0+
	/*
	* Helpers for controlling modem lines via GPIO
	*
	* Copyright (C) 2014 Paratronic S.A.
	*/

	#include <linux/err.h>
	#include <linux/device.h>
	#include <linux/irq.h>
	#include <linux/gpio/consumer.h>
	#include <linux/termios.h>
	#include <linux/serial_core.h>
	#include <linux/module.h>
	#include <linux/property.h>

	#include "serial_mctrl_gpio.h"

	struct mctrl_gpios {
	struct uart_port *port;
	struct gpio_desc *gpio[UART_GPIO_MAX];
	int irq[UART_GPIO_MAX];
	unsigned int mctrl_prev;
	bool mctrl_on;
	};

	static const struct {
	const char *name;
	unsigned int mctrl;
	enum gpiod_flags flags;
	} mctrl_gpios_desc[UART_GPIO_MAX] = {
	{ "cts", TIOCM_CTS, GPIOD_IN, },
	{ "dsr", TIOCM_DSR, GPIOD_IN, },
	{ "dcd", TIOCM_CD, GPIOD_IN, },
	{ "rng", TIOCM_RNG, GPIOD_IN, },
	{ "rts", TIOCM_RTS, GPIOD_OUT_LOW, },
	{ "dtr", TIOCM_DTR, GPIOD_OUT_LOW, },
	};

	static bool mctrl_gpio_flags_is_dir_out(unsigned int idx)
	{
	return mctrl_gpios_desc[idx].flags & GPIOD_FLAGS_BIT_DIR_OUT;
	}

	/**
	* mctrl_gpio_set - set gpios according to mctrl state
	* @gpios: gpios to set
	* @mctrl: state to set
	*
	* Set the gpios according to the mctrl state.
	*/
	void mctrl_gpio_set(struct mctrl_gpios *gpios, unsigned int mctrl)
	{
	enum mctrl_gpio_idx i;
	struct gpio_desc *desc_array[UART_GPIO_MAX];
	DECLARE_BITMAP(values, UART_GPIO_MAX);
	unsigned int count = 0;

	if (gpios == NULL)
	return;

	for (i = 0; i < UART_GPIO_MAX; i++)
	if (gpios->gpio[i] && mctrl_gpio_flags_is_dir_out(i)) {
	desc_array[count] = gpios->gpio[i];
	__assign_bit(count, values,
	mctrl & mctrl_gpios_desc[i].mctrl);
	count++;
	}
	gpiod_set_array_value(count, desc_array, NULL, values);
	}
	EXPORT_SYMBOL_GPL(mctrl_gpio_set);

	/**
	* mctrl_gpio_to_gpiod - obtain gpio_desc of modem line index
	* @gpios: gpios to look into
	* @gidx: index of the modem line
	* Returns: the gpio_desc structure associated to the modem line index
	*/
	struct gpio_desc mctrl_gpio_to_gpiod(struct mctrl_gpios gpios,
	enum mctrl_gpio_idx gidx)
	{
	if (gpios == NULL)
	return NULL;

	return gpios->gpio[gidx];
	}
	EXPORT_SYMBOL_GPL(mctrl_gpio_to_gpiod);

	/**
	* mctrl_gpio_get - update mctrl with the gpios values.
	* @gpios: gpios to get the info from
	* @mctrl: mctrl to set
	* Returns: modified mctrl (the same value as in @mctrl)
	*
	* Update mctrl with the gpios values.
	*/
	unsigned int mctrl_gpio_get(struct mctrl_gpios gpios, unsigned int mctrl)
	{
	enum mctrl_gpio_idx i;

	if (gpios == NULL)
	return *mctrl;

	for (i = 0; i < UART_GPIO_MAX; i++) {
	if (gpios->gpio[i] && !mctrl_gpio_flags_is_dir_out(i)) {
	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);

	unsigned int
	mctrl_gpio_get_outputs(struct mctrl_gpios gpios, unsigned int mctrl)
	{
	enum mctrl_gpio_idx i;

	if (gpios == NULL)
	return *mctrl;

	for (i = 0; i < UART_GPIO_MAX; i++) {
	if (gpios->gpio[i] && mctrl_gpio_flags_is_dir_out(i)) {
	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_outputs);

	struct mctrl_gpios mctrl_gpio_init_noauto(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++) {
	char *gpio_str;
	bool present;

	/* Check if GPIO property exists and continue if not */
	gpio_str = kasprintf(GFP_KERNEL, "%s-gpios",
	mctrl_gpios_desc[i].name);
	if (!gpio_str)
	continue;

	present = device_property_present(dev, gpio_str);
	kfree(gpio_str);
	if (!present)
	continue;

	gpios->gpio[i] =
	devm_gpiod_get_index_optional(dev,
	mctrl_gpios_desc[i].name,
	idx,
	mctrl_gpios_desc[i].flags);

	if (IS_ERR(gpios->gpio[i]))
	return ERR_CAST(gpios->gpio[i]);
	}

	return gpios;
	}
	EXPORT_SYMBOL_GPL(mctrl_gpio_init_noauto);

	#define MCTRL_ANY_DELTA (TIOCM_RI \| TIOCM_DSR \| TIOCM_CD \| TIOCM_CTS)
	static irqreturn_t mctrl_gpio_irq_handle(int irq, void *context)
	{
	struct mctrl_gpios *gpios = context;
	struct uart_port *port = gpios->port;
	u32 mctrl = gpios->mctrl_prev;
	u32 mctrl_diff;
	unsigned long flags;

	mctrl_gpio_get(gpios, &mctrl);

	uart_port_lock_irqsave(port, &flags);

	mctrl_diff = mctrl ^ gpios->mctrl_prev;
	gpios->mctrl_prev = mctrl;

	if (mctrl_diff & MCTRL_ANY_DELTA && port->state != NULL) {
	if ((mctrl_diff & mctrl) & TIOCM_RI)
	port->icount.rng++;

	if ((mctrl_diff & mctrl) & TIOCM_DSR)
	port->icount.dsr++;

	if (mctrl_diff & TIOCM_CD)
	uart_handle_dcd_change(port, mctrl & TIOCM_CD);

	if (mctrl_diff & TIOCM_CTS)
	uart_handle_cts_change(port, mctrl & TIOCM_CTS);

	wake_up_interruptible(&port->state->port.delta_msr_wait);
	}

	uart_port_unlock_irqrestore(port, flags);

	return IRQ_HANDLED;
	}

	/**
	* mctrl_gpio_init - initialize uart gpios
	* @port: port to initialize gpios for
	* @idx: index of the gpio in the @port's device
	*
	* This will get the {cts,rts,...}-gpios from device tree if they are present
	* and request them, set direction etc, and return an allocated structure.
	* `devm_*` functions are used, so there's no need to call mctrl_gpio_free().
	* As this sets up the irq handling, make sure to not handle changes to the
	* gpio input lines in your driver, too.
	*/
	struct mctrl_gpios mctrl_gpio_init(struct uart_port port, unsigned int idx)
	{
	struct mctrl_gpios *gpios;
	enum mctrl_gpio_idx i;

	gpios = mctrl_gpio_init_noauto(port->dev, idx);
	if (IS_ERR(gpios))
	return gpios;

	gpios->port = port;

	for (i = 0; i < UART_GPIO_MAX; ++i) {
	int ret;

	if (!gpios->gpio[i] \|\| mctrl_gpio_flags_is_dir_out(i))
	continue;

	ret = gpiod_to_irq(gpios->gpio[i]);
	if (ret < 0) {
	dev_err(port->dev,
	"failed to find corresponding irq for %s (idx=%d, err=%d)\n",
	mctrl_gpios_desc[i].name, idx, ret);
	return ERR_PTR(ret);
	}
	gpios->irq[i] = ret;

	/* irqs should only be enabled in .enable_ms */
	irq_set_status_flags(gpios->irq[i], IRQ_NOAUTOEN);

	ret = devm_request_irq(port->dev, gpios->irq[i],
	mctrl_gpio_irq_handle,
	IRQ_TYPE_EDGE_BOTH, dev_name(port->dev),
	gpios);
	if (ret) {
	/* alternatively implement polling */
	dev_err(port->dev,
	"failed to request irq for %s (idx=%d, err=%d)\n",
	mctrl_gpios_desc[i].name, idx, ret);
	return ERR_PTR(ret);
	}
	}

	return gpios;
	}
	EXPORT_SYMBOL_GPL(mctrl_gpio_init);

	/**
	* mctrl_gpio_free - explicitly free uart gpios
	* @dev: uart port's device
	* @gpios: gpios structure to be freed
	*
	* This will free the requested gpios in mctrl_gpio_init(). As `devm_*`
	* functions are used, there's generally no need to call this function.
	*/
	void mctrl_gpio_free(struct device dev, struct mctrl_gpios gpios)
	{
	enum mctrl_gpio_idx i;

	if (gpios == NULL)
	return;

	for (i = 0; i < UART_GPIO_MAX; i++) {
	if (gpios->irq[i])
	devm_free_irq(gpios->port->dev, gpios->irq[i], gpios);

	if (gpios->gpio[i])
	devm_gpiod_put(dev, gpios->gpio[i]);
	}
	devm_kfree(dev, gpios);
	}
	EXPORT_SYMBOL_GPL(mctrl_gpio_free);

	/**
	* mctrl_gpio_enable_ms - enable irqs and handling of changes to the ms lines
	* @gpios: gpios to enable
	*/
	void mctrl_gpio_enable_ms(struct mctrl_gpios *gpios)
	{
	enum mctrl_gpio_idx i;

	if (gpios == NULL)
	return;

	/* .enable_ms may be called multiple times */
	if (gpios->mctrl_on)
	return;

	gpios->mctrl_on = true;

	/* get initial status of modem lines GPIOs */
	mctrl_gpio_get(gpios, &gpios->mctrl_prev);

	for (i = 0; i < UART_GPIO_MAX; ++i) {
	if (!gpios->irq[i])
	continue;

	enable_irq(gpios->irq[i]);
	}
	}
	EXPORT_SYMBOL_GPL(mctrl_gpio_enable_ms);

	static void mctrl_gpio_disable_ms(struct mctrl_gpios *gpios, bool sync)
	{
	enum mctrl_gpio_idx i;

	if (gpios == NULL)
	return;

	if (!gpios->mctrl_on)
	return;

	gpios->mctrl_on = false;

	for (i = 0; i < UART_GPIO_MAX; ++i) {
	if (!gpios->irq[i])
	continue;

	if (sync)
	disable_irq(gpios->irq[i]);
	else
	disable_irq_nosync(gpios->irq[i]);
	}
	}

	/**
	* mctrl_gpio_disable_ms_sync - disable irqs and handling of changes to the ms
	* lines, and wait for any pending IRQ to be processed
	* @gpios: gpios to disable
	*/
	void mctrl_gpio_disable_ms_sync(struct mctrl_gpios *gpios)
	{
	mctrl_gpio_disable_ms(gpios, true);
	}
	EXPORT_SYMBOL_GPL(mctrl_gpio_disable_ms_sync);

	/**
	* mctrl_gpio_disable_ms_no_sync - disable irqs and handling of changes to the
	* ms lines, and return immediately
	* @gpios: gpios to disable
	*/
	void mctrl_gpio_disable_ms_no_sync(struct mctrl_gpios *gpios)
	{
	mctrl_gpio_disable_ms(gpios, false);
	}
	EXPORT_SYMBOL_GPL(mctrl_gpio_disable_ms_no_sync);

	void mctrl_gpio_enable_irq_wake(struct mctrl_gpios *gpios)
	{
	enum mctrl_gpio_idx i;

	if (!gpios)
	return;

	if (!gpios->mctrl_on)
	return;

	for (i = 0; i < UART_GPIO_MAX; ++i) {
	if (!gpios->irq[i])
	continue;

	enable_irq_wake(gpios->irq[i]);
	}
	}
	EXPORT_SYMBOL_GPL(mctrl_gpio_enable_irq_wake);

	void mctrl_gpio_disable_irq_wake(struct mctrl_gpios *gpios)
	{
	enum mctrl_gpio_idx i;

	if (!gpios)
	return;

	if (!gpios->mctrl_on)
	return;

	for (i = 0; i < UART_GPIO_MAX; ++i) {
	if (!gpios->irq[i])
	continue;

	disable_irq_wake(gpios->irq[i]);
	}
	}
	EXPORT_SYMBOL_GPL(mctrl_gpio_disable_irq_wake);

	MODULE_DESCRIPTION("Helpers for controlling modem lines via GPIO");
	MODULE_LICENSE("GPL");