drivers/soc/fsl/qe/gpio.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * QUICC Engine GPIOs
  *
  * Copyright (c) MontaVista Software, Inc. 2008.
  *
  * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
  */

 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/spinlock.h>
 #include <linux/err.h>
 #include <linux/io.h>
 #include <linux/of.h>
 #include <linux/gpio/legacy-of-mm-gpiochip.h>
 #include <linux/gpio/consumer.h>
 #include <linux/gpio/driver.h>
 #include <linux/slab.h>
 #include <linux/export.h>
 #include <linux/property.h>

 #include <soc/fsl/qe/qe.h>

 struct qe_gpio_chip {
 	struct of_mm_gpio_chip mm_gc;
 	spinlock_t lock;

 	/* shadowed data register to clear/set bits safely */
 	u32 cpdata;

 	/* saved_regs used to restore dedicated functions */
 	struct qe_pio_regs saved_regs;
 };

 static void qe_gpio_save_regs(struct of_mm_gpio_chip *mm_gc)
 {
 	struct qe_gpio_chip *qe_gc =
 		container_of(mm_gc, struct qe_gpio_chip, mm_gc);
 	struct qe_pio_regs __iomem *regs = mm_gc->regs;

 	qe_gc->cpdata = ioread32be(&regs->cpdata);
 	qe_gc->saved_regs.cpdata = qe_gc->cpdata;
 	qe_gc->saved_regs.cpdir1 = ioread32be(&regs->cpdir1);
 	qe_gc->saved_regs.cpdir2 = ioread32be(&regs->cpdir2);
 	qe_gc->saved_regs.cppar1 = ioread32be(&regs->cppar1);
 	qe_gc->saved_regs.cppar2 = ioread32be(&regs->cppar2);
 	qe_gc->saved_regs.cpodr = ioread32be(&regs->cpodr);
 }

 static int qe_gpio_get(struct gpio_chip *gc, unsigned int gpio)
 {
 	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
 	struct qe_pio_regs __iomem *regs = mm_gc->regs;
 	u32 pin_mask = 1 << (QE_PIO_PINS - 1 - gpio);

 	return !!(ioread32be(&regs->cpdata) & pin_mask);
 }

 static void qe_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
 {
 	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
 	struct qe_gpio_chip *qe_gc = gpiochip_get_data(gc);
 	struct qe_pio_regs __iomem *regs = mm_gc->regs;
 	unsigned long flags;
 	u32 pin_mask = 1 << (QE_PIO_PINS - 1 - gpio);

 	spin_lock_irqsave(&qe_gc->lock, flags);

 	if (val)
 		qe_gc->cpdata |= pin_mask;
 	else
 		qe_gc->cpdata &= ~pin_mask;

 	iowrite32be(qe_gc->cpdata, &regs->cpdata);

 	spin_unlock_irqrestore(&qe_gc->lock, flags);
 }

 static void qe_gpio_set_multiple(struct gpio_chip *gc,
 				 unsigned long *mask, unsigned long *bits)
 {
 	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
 	struct qe_gpio_chip *qe_gc = gpiochip_get_data(gc);
 	struct qe_pio_regs __iomem *regs = mm_gc->regs;
 	unsigned long flags;
 	int i;

 	spin_lock_irqsave(&qe_gc->lock, flags);

 	for (i = 0; i < gc->ngpio; i++) {
 		if (*mask == 0)
 			break;
 		if (__test_and_clear_bit(i, mask)) {
 			if (test_bit(i, bits))
 				qe_gc->cpdata |= (1U << (QE_PIO_PINS - 1 - i));
 			else
 				qe_gc->cpdata &= ~(1U << (QE_PIO_PINS - 1 - i));
 		}
 	}

 	iowrite32be(qe_gc->cpdata, &regs->cpdata);

 	spin_unlock_irqrestore(&qe_gc->lock, flags);
 }

 static int qe_gpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
 {
 	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
 	struct qe_gpio_chip *qe_gc = gpiochip_get_data(gc);
 	unsigned long flags;

 	spin_lock_irqsave(&qe_gc->lock, flags);

 	__par_io_config_pin(mm_gc->regs, gpio, QE_PIO_DIR_IN, 0, 0, 0);

 	spin_unlock_irqrestore(&qe_gc->lock, flags);

 	return 0;
 }

 static int qe_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
 {
 	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
 	struct qe_gpio_chip *qe_gc = gpiochip_get_data(gc);
 	unsigned long flags;

 	qe_gpio_set(gc, gpio, val);

 	spin_lock_irqsave(&qe_gc->lock, flags);

 	__par_io_config_pin(mm_gc->regs, gpio, QE_PIO_DIR_OUT, 0, 0, 0);

 	spin_unlock_irqrestore(&qe_gc->lock, flags);

 	return 0;
 }

 struct qe_pin {
 	/*
 	 * The qe_gpio_chip name is unfortunate, we should change that to
 	 * something like qe_pio_controller. Someday.
 	 */
 	struct qe_gpio_chip *controller;
 	int num;
 };

 /**
  * qe_pin_request - Request a QE pin
  * @dev:	device to get the pin from
  * @index:	index of the pin in the device tree
  * Context:	non-atomic
  *
  * This function return qe_pin so that you could use it with the rest of
  * the QE Pin Multiplexing API.
  */
 struct qe_pin *qe_pin_request(struct device *dev, int index)
 {
 	struct qe_pin *qe_pin;
 	struct gpio_chip *gc;
 	struct gpio_desc *gpiod;
 	int gpio_num;
 	int err;

 	qe_pin = kzalloc(sizeof(*qe_pin), GFP_KERNEL);
 	if (!qe_pin) {
 		dev_dbg(dev, "%s: can't allocate memory\n", __func__);
 		return ERR_PTR(-ENOMEM);
 	}

 	/*
 	 * Request gpio as nonexclusive as it was likely reserved by the
 	 * caller, and we are not planning on controlling it, we only need
 	 * the descriptor to the to the gpio chip structure.
 	 */
 	gpiod = gpiod_get_index(dev, NULL, index,
 			        GPIOD_ASIS | GPIOD_FLAGS_BIT_NONEXCLUSIVE);
 	err = PTR_ERR_OR_ZERO(gpiod);
 	if (err)
 		goto err0;

 	gc = gpiod_to_chip(gpiod);
 	gpio_num = desc_to_gpio(gpiod);
 	/* We no longer need this descriptor */
 	gpiod_put(gpiod);

 	if (WARN_ON(!gc)) {
 		err = -ENODEV;
 		goto err0;
 	}

 	qe_pin->controller = gpiochip_get_data(gc);
 	/*
 	 * FIXME: this gets the local offset on the gpio_chip so that the driver
 	 * can manipulate pin control settings through its custom API. The real
 	 * solution is to create a real pin control driver for this.
 	 */
 	qe_pin->num = gpio_num - gc->base;

 	if (!fwnode_device_is_compatible(gc->fwnode, "fsl,mpc8323-qe-pario-bank")) {
 		dev_dbg(dev, "%s: tried to get a non-qe pin\n", __func__);
 		err = -EINVAL;
 		goto err0;
 	}
 	return qe_pin;
 err0:
 	kfree(qe_pin);
 	dev_dbg(dev, "%s failed with status %d\n", __func__, err);
 	return ERR_PTR(err);
 }
 EXPORT_SYMBOL(qe_pin_request);

 /**
  * qe_pin_free - Free a pin
  * @qe_pin:	pointer to the qe_pin structure
  * Context:	any
  *
  * This function frees the qe_pin structure and makes a pin available
  * for further qe_pin_request() calls.
  */
 void qe_pin_free(struct qe_pin *qe_pin)
 {
 	kfree(qe_pin);
 }
 EXPORT_SYMBOL(qe_pin_free);

 /**
  * qe_pin_set_dedicated - Revert a pin to a dedicated peripheral function mode
  * @qe_pin:	pointer to the qe_pin structure
  * Context:	any
  *
  * This function resets a pin to a dedicated peripheral function that
  * has been set up by the firmware.
  */
 void qe_pin_set_dedicated(struct qe_pin *qe_pin)
 {
 	struct qe_gpio_chip *qe_gc = qe_pin->controller;
 	struct qe_pio_regs __iomem *regs = qe_gc->mm_gc.regs;
 	struct qe_pio_regs *sregs = &qe_gc->saved_regs;
 	int pin = qe_pin->num;
 	u32 mask1 = 1 << (QE_PIO_PINS - (pin + 1));
 	u32 mask2 = 0x3 << (QE_PIO_PINS - (pin % (QE_PIO_PINS / 2) + 1) * 2);
 	bool second_reg = pin > (QE_PIO_PINS / 2) - 1;
 	unsigned long flags;

 	spin_lock_irqsave(&qe_gc->lock, flags);

 	if (second_reg) {
 		qe_clrsetbits_be32(&regs->cpdir2, mask2,
 				   sregs->cpdir2 & mask2);
 		qe_clrsetbits_be32(&regs->cppar2, mask2,
 				   sregs->cppar2 & mask2);
 	} else {
 		qe_clrsetbits_be32(&regs->cpdir1, mask2,
 				   sregs->cpdir1 & mask2);
 		qe_clrsetbits_be32(&regs->cppar1, mask2,
 				   sregs->cppar1 & mask2);
 	}

 	if (sregs->cpdata & mask1)
 		qe_gc->cpdata |= mask1;
 	else
 		qe_gc->cpdata &= ~mask1;

 	iowrite32be(qe_gc->cpdata, &regs->cpdata);
 	qe_clrsetbits_be32(&regs->cpodr, mask1, sregs->cpodr & mask1);

 	spin_unlock_irqrestore(&qe_gc->lock, flags);
 }
 EXPORT_SYMBOL(qe_pin_set_dedicated);

 /**
  * qe_pin_set_gpio - Set a pin to the GPIO mode
  * @qe_pin:	pointer to the qe_pin structure
  * Context:	any
  *
  * This function sets a pin to the GPIO mode.
  */
 void qe_pin_set_gpio(struct qe_pin *qe_pin)
 {
 	struct qe_gpio_chip *qe_gc = qe_pin->controller;
 	struct qe_pio_regs __iomem *regs = qe_gc->mm_gc.regs;
 	unsigned long flags;

 	spin_lock_irqsave(&qe_gc->lock, flags);

 	/* Let's make it input by default, GPIO API is able to change that. */
 	__par_io_config_pin(regs, qe_pin->num, QE_PIO_DIR_IN, 0, 0, 0);

 	spin_unlock_irqrestore(&qe_gc->lock, flags);
 }
 EXPORT_SYMBOL(qe_pin_set_gpio);

 static int __init qe_add_gpiochips(void)
 {
 	struct device_node *np;

 	for_each_compatible_node(np, NULL, "fsl,mpc8323-qe-pario-bank") {
 		int ret;
 		struct qe_gpio_chip *qe_gc;
 		struct of_mm_gpio_chip *mm_gc;
 		struct gpio_chip *gc;

 		qe_gc = kzalloc(sizeof(*qe_gc), GFP_KERNEL);
 		if (!qe_gc) {
 			ret = -ENOMEM;
 			goto err;
 		}

 		spin_lock_init(&qe_gc->lock);

 		mm_gc = &qe_gc->mm_gc;
 		gc = &mm_gc->gc;

 		mm_gc->save_regs = qe_gpio_save_regs;
 		gc->ngpio = QE_PIO_PINS;
 		gc->direction_input = qe_gpio_dir_in;
 		gc->direction_output = qe_gpio_dir_out;
 		gc->get = qe_gpio_get;
 		gc->set = qe_gpio_set;
 		gc->set_multiple = qe_gpio_set_multiple;

 		ret = of_mm_gpiochip_add_data(np, mm_gc, qe_gc);
 		if (ret)
 			goto err;
 		continue;
 err:
 		pr_err("%pOF: registration failed with status %d\n",
 		       np, ret);
 		kfree(qe_gc);
 		/* try others anyway */
 	}
 	return 0;
 }
 arch_initcall(qe_add_gpiochips);
	// SPDX-License-Identifier: GPL-2.0-or-later
	/*
	* QUICC Engine GPIOs
	*
	* Copyright (c) MontaVista Software, Inc. 2008.
	*
	* Author: Anton Vorontsov <avorontsov@ru.mvista.com>
	*/

	#include <linux/kernel.h>
	#include <linux/init.h>
	#include <linux/spinlock.h>
	#include <linux/err.h>
	#include <linux/io.h>
	#include <linux/of.h>
	#include <linux/gpio/legacy-of-mm-gpiochip.h>
	#include <linux/gpio/consumer.h>
	#include <linux/gpio/driver.h>
	#include <linux/slab.h>
	#include <linux/export.h>
	#include <linux/property.h>

	#include <soc/fsl/qe/qe.h>

	struct qe_gpio_chip {
	struct of_mm_gpio_chip mm_gc;
	spinlock_t lock;

	/* shadowed data register to clear/set bits safely */
	u32 cpdata;

	/* saved_regs used to restore dedicated functions */
	struct qe_pio_regs saved_regs;
	};

	static void qe_gpio_save_regs(struct of_mm_gpio_chip *mm_gc)
	{
	struct qe_gpio_chip *qe_gc =
	container_of(mm_gc, struct qe_gpio_chip, mm_gc);
	struct qe_pio_regs __iomem *regs = mm_gc->regs;

	qe_gc->cpdata = ioread32be(&regs->cpdata);
	qe_gc->saved_regs.cpdata = qe_gc->cpdata;
	qe_gc->saved_regs.cpdir1 = ioread32be(&regs->cpdir1);
	qe_gc->saved_regs.cpdir2 = ioread32be(&regs->cpdir2);
	qe_gc->saved_regs.cppar1 = ioread32be(&regs->cppar1);
	qe_gc->saved_regs.cppar2 = ioread32be(&regs->cppar2);
	qe_gc->saved_regs.cpodr = ioread32be(&regs->cpodr);
	}

	static int qe_gpio_get(struct gpio_chip *gc, unsigned int gpio)
	{
	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
	struct qe_pio_regs __iomem *regs = mm_gc->regs;
	u32 pin_mask = 1 << (QE_PIO_PINS - 1 - gpio);

	return !!(ioread32be(&regs->cpdata) & pin_mask);
	}

	static void qe_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
	{
	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
	struct qe_gpio_chip *qe_gc = gpiochip_get_data(gc);
	struct qe_pio_regs __iomem *regs = mm_gc->regs;
	unsigned long flags;
	u32 pin_mask = 1 << (QE_PIO_PINS - 1 - gpio);

	spin_lock_irqsave(&qe_gc->lock, flags);

	if (val)
	qe_gc->cpdata \|= pin_mask;
	else
	qe_gc->cpdata &= ~pin_mask;

	iowrite32be(qe_gc->cpdata, &regs->cpdata);

	spin_unlock_irqrestore(&qe_gc->lock, flags);
	}

	static void qe_gpio_set_multiple(struct gpio_chip *gc,
	unsigned long mask, unsigned long bits)
	{
	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
	struct qe_gpio_chip *qe_gc = gpiochip_get_data(gc);
	struct qe_pio_regs __iomem *regs = mm_gc->regs;
	unsigned long flags;
	int i;

	spin_lock_irqsave(&qe_gc->lock, flags);

	for (i = 0; i < gc->ngpio; i++) {
	if (*mask == 0)
	break;
	if (__test_and_clear_bit(i, mask)) {
	if (test_bit(i, bits))
	qe_gc->cpdata \|= (1U << (QE_PIO_PINS - 1 - i));
	else
	qe_gc->cpdata &= ~(1U << (QE_PIO_PINS - 1 - i));
	}
	}

	iowrite32be(qe_gc->cpdata, &regs->cpdata);

	spin_unlock_irqrestore(&qe_gc->lock, flags);
	}

	static int qe_gpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
	{
	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
	struct qe_gpio_chip *qe_gc = gpiochip_get_data(gc);
	unsigned long flags;

	spin_lock_irqsave(&qe_gc->lock, flags);

	__par_io_config_pin(mm_gc->regs, gpio, QE_PIO_DIR_IN, 0, 0, 0);

	spin_unlock_irqrestore(&qe_gc->lock, flags);

	return 0;
	}

	static int qe_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
	{
	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
	struct qe_gpio_chip *qe_gc = gpiochip_get_data(gc);
	unsigned long flags;

	qe_gpio_set(gc, gpio, val);

	spin_lock_irqsave(&qe_gc->lock, flags);

	__par_io_config_pin(mm_gc->regs, gpio, QE_PIO_DIR_OUT, 0, 0, 0);

	spin_unlock_irqrestore(&qe_gc->lock, flags);

	return 0;
	}

	struct qe_pin {
	/*
	* The qe_gpio_chip name is unfortunate, we should change that to
	* something like qe_pio_controller. Someday.
	*/
	struct qe_gpio_chip *controller;
	int num;
	};

	/**
	* qe_pin_request - Request a QE pin
	* @dev: device to get the pin from
	* @index: index of the pin in the device tree
	* Context: non-atomic
	*
	* This function return qe_pin so that you could use it with the rest of
	* the QE Pin Multiplexing API.
	*/
	struct qe_pin qe_pin_request(struct device dev, int index)
	{
	struct qe_pin *qe_pin;
	struct gpio_chip *gc;
	struct gpio_desc *gpiod;
	int gpio_num;
	int err;

	qe_pin = kzalloc(sizeof(*qe_pin), GFP_KERNEL);
	if (!qe_pin) {
	dev_dbg(dev, "%s: can't allocate memory\n", __func__);
	return ERR_PTR(-ENOMEM);
	}

	/*
	* Request gpio as nonexclusive as it was likely reserved by the
	* caller, and we are not planning on controlling it, we only need
	* the descriptor to the to the gpio chip structure.
	*/
	gpiod = gpiod_get_index(dev, NULL, index,
	GPIOD_ASIS \| GPIOD_FLAGS_BIT_NONEXCLUSIVE);
	err = PTR_ERR_OR_ZERO(gpiod);
	if (err)
	goto err0;

	gc = gpiod_to_chip(gpiod);
	gpio_num = desc_to_gpio(gpiod);
	/* We no longer need this descriptor */
	gpiod_put(gpiod);

	if (WARN_ON(!gc)) {
	err = -ENODEV;
	goto err0;
	}

	qe_pin->controller = gpiochip_get_data(gc);
	/*
	* FIXME: this gets the local offset on the gpio_chip so that the driver
	* can manipulate pin control settings through its custom API. The real
	* solution is to create a real pin control driver for this.
	*/
	qe_pin->num = gpio_num - gc->base;

	if (!fwnode_device_is_compatible(gc->fwnode, "fsl,mpc8323-qe-pario-bank")) {
	dev_dbg(dev, "%s: tried to get a non-qe pin\n", __func__);
	err = -EINVAL;
	goto err0;
	}
	return qe_pin;
	err0:
	kfree(qe_pin);
	dev_dbg(dev, "%s failed with status %d\n", __func__, err);
	return ERR_PTR(err);
	}
	EXPORT_SYMBOL(qe_pin_request);

	/**
	* qe_pin_free - Free a pin
	* @qe_pin: pointer to the qe_pin structure
	* Context: any
	*
	* This function frees the qe_pin structure and makes a pin available
	* for further qe_pin_request() calls.
	*/
	void qe_pin_free(struct qe_pin *qe_pin)
	{
	kfree(qe_pin);
	}
	EXPORT_SYMBOL(qe_pin_free);

	/**
	* qe_pin_set_dedicated - Revert a pin to a dedicated peripheral function mode
	* @qe_pin: pointer to the qe_pin structure
	* Context: any
	*
	* This function resets a pin to a dedicated peripheral function that
	* has been set up by the firmware.
	*/
	void qe_pin_set_dedicated(struct qe_pin *qe_pin)
	{
	struct qe_gpio_chip *qe_gc = qe_pin->controller;
	struct qe_pio_regs __iomem *regs = qe_gc->mm_gc.regs;
	struct qe_pio_regs *sregs = &qe_gc->saved_regs;
	int pin = qe_pin->num;
	u32 mask1 = 1 << (QE_PIO_PINS - (pin + 1));
	u32 mask2 = 0x3 << (QE_PIO_PINS - (pin % (QE_PIO_PINS / 2) + 1) * 2);
	bool second_reg = pin > (QE_PIO_PINS / 2) - 1;
	unsigned long flags;

	spin_lock_irqsave(&qe_gc->lock, flags);

	if (second_reg) {
	qe_clrsetbits_be32(&regs->cpdir2, mask2,
	sregs->cpdir2 & mask2);
	qe_clrsetbits_be32(&regs->cppar2, mask2,
	sregs->cppar2 & mask2);
	} else {
	qe_clrsetbits_be32(&regs->cpdir1, mask2,
	sregs->cpdir1 & mask2);
	qe_clrsetbits_be32(&regs->cppar1, mask2,
	sregs->cppar1 & mask2);
	}

	if (sregs->cpdata & mask1)
	qe_gc->cpdata \|= mask1;
	else
	qe_gc->cpdata &= ~mask1;

	iowrite32be(qe_gc->cpdata, &regs->cpdata);
	qe_clrsetbits_be32(&regs->cpodr, mask1, sregs->cpodr & mask1);

	spin_unlock_irqrestore(&qe_gc->lock, flags);
	}
	EXPORT_SYMBOL(qe_pin_set_dedicated);

	/**
	* qe_pin_set_gpio - Set a pin to the GPIO mode
	* @qe_pin: pointer to the qe_pin structure
	* Context: any
	*
	* This function sets a pin to the GPIO mode.
	*/
	void qe_pin_set_gpio(struct qe_pin *qe_pin)
	{
	struct qe_gpio_chip *qe_gc = qe_pin->controller;
	struct qe_pio_regs __iomem *regs = qe_gc->mm_gc.regs;
	unsigned long flags;

	spin_lock_irqsave(&qe_gc->lock, flags);

	/* Let's make it input by default, GPIO API is able to change that. */
	__par_io_config_pin(regs, qe_pin->num, QE_PIO_DIR_IN, 0, 0, 0);

	spin_unlock_irqrestore(&qe_gc->lock, flags);
	}
	EXPORT_SYMBOL(qe_pin_set_gpio);

	static int __init qe_add_gpiochips(void)
	{
	struct device_node *np;

	for_each_compatible_node(np, NULL, "fsl,mpc8323-qe-pario-bank") {
	int ret;
	struct qe_gpio_chip *qe_gc;
	struct of_mm_gpio_chip *mm_gc;
	struct gpio_chip *gc;

	qe_gc = kzalloc(sizeof(*qe_gc), GFP_KERNEL);
	if (!qe_gc) {
	ret = -ENOMEM;
	goto err;
	}

	spin_lock_init(&qe_gc->lock);

	mm_gc = &qe_gc->mm_gc;
	gc = &mm_gc->gc;

	mm_gc->save_regs = qe_gpio_save_regs;
	gc->ngpio = QE_PIO_PINS;
	gc->direction_input = qe_gpio_dir_in;
	gc->direction_output = qe_gpio_dir_out;
	gc->get = qe_gpio_get;
	gc->set = qe_gpio_set;
	gc->set_multiple = qe_gpio_set_multiple;

	ret = of_mm_gpiochip_add_data(np, mm_gc, qe_gc);
	if (ret)
	goto err;
	continue;
	err:
	pr_err("%pOF: registration failed with status %d\n",
	np, ret);
	kfree(qe_gc);
	/* try others anyway */
	}
	return 0;
	}
	arch_initcall(qe_add_gpiochips);