drivers/gpio/gpio-pci-idio-16.c - kernel/msm-4.19 - Gitiles

 /*
  * GPIO driver for the ACCES PCI-IDIO-16
  * Copyright (C) 2017 William Breathitt Gray
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License, version 2, as
  * published by the Free Software Foundation.
  *
  * 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/bitops.h>
 #include <linux/device.h>
 #include <linux/errno.h>
 #include <linux/gpio/driver.h>
 #include <linux/interrupt.h>
 #include <linux/irqdesc.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/pci.h>
 #include <linux/spinlock.h>
 #include <linux/types.h>

 /**
  * struct idio_16_gpio_reg - GPIO device registers structure
  * @out0_7:	Read: FET Drive Outputs 0-7
  *		Write: FET Drive Outputs 0-7
  * @in0_7:	Read: Isolated Inputs 0-7
  *		Write: Clear Interrupt
  * @irq_ctl:	Read: Enable IRQ
  *		Write: Disable IRQ
  * @filter_ctl:	Read: Activate Input Filters 0-15
  *		Write: Deactivate Input Filters 0-15
  * @out8_15:	Read: FET Drive Outputs 8-15
  *		Write: FET Drive Outputs 8-15
  * @in8_15:	Read: Isolated Inputs 8-15
  *		Write: Unused
  * @irq_status:	Read: Interrupt status
  *		Write: Unused
  */
 struct idio_16_gpio_reg {
 	u8 out0_7;
 	u8 in0_7;
 	u8 irq_ctl;
 	u8 filter_ctl;
 	u8 out8_15;
 	u8 in8_15;
 	u8 irq_status;
 };

 /**
  * struct idio_16_gpio - GPIO device private data structure
  * @chip:	instance of the gpio_chip
  * @lock:	synchronization lock to prevent I/O race conditions
  * @reg:	I/O address offset for the GPIO device registers
  * @irq_mask:	I/O bits affected by interrupts
  */
 struct idio_16_gpio {
 	struct gpio_chip chip;
 	spinlock_t lock;
 	struct idio_16_gpio_reg __iomem *reg;
 	unsigned long irq_mask;
 };

 static int idio_16_gpio_get_direction(struct gpio_chip *chip,
 	unsigned int offset)
 {
 	if (offset > 15)
 		return 1;

 	return 0;
 }

 static int idio_16_gpio_direction_input(struct gpio_chip *chip,
 	unsigned int offset)
 {
 	return 0;
 }

 static int idio_16_gpio_direction_output(struct gpio_chip *chip,
 	unsigned int offset, int value)
 {
 	chip->set(chip, offset, value);
 	return 0;
 }

 static int idio_16_gpio_get(struct gpio_chip *chip, unsigned int offset)
 {
 	struct idio_16_gpio *const idio16gpio = gpiochip_get_data(chip);
 	unsigned long mask = BIT(offset);

 	if (offset < 8)
 		return !!(ioread8(&idio16gpio->reg->out0_7) & mask);

 	if (offset < 16)
 		return !!(ioread8(&idio16gpio->reg->out8_15) & (mask >> 8));

 	if (offset < 24)
 		return !!(ioread8(&idio16gpio->reg->in0_7) & (mask >> 16));

 	return !!(ioread8(&idio16gpio->reg->in8_15) & (mask >> 24));
 }

 static void idio_16_gpio_set(struct gpio_chip *chip, unsigned int offset,
 	int value)
 {
 	struct idio_16_gpio *const idio16gpio = gpiochip_get_data(chip);
 	unsigned int mask = BIT(offset);
 	void __iomem *base;
 	unsigned long flags;
 	unsigned int out_state;

 	if (offset > 15)
 		return;

 	if (offset > 7) {
 		mask >>= 8;
 		base = &idio16gpio->reg->out8_15;
 	} else
 		base = &idio16gpio->reg->out0_7;

 	spin_lock_irqsave(&idio16gpio->lock, flags);

 	if (value)
 		out_state = ioread8(base) | mask;
 	else
 		out_state = ioread8(base) & ~mask;

 	iowrite8(out_state, base);

 	spin_unlock_irqrestore(&idio16gpio->lock, flags);
 }

 static void idio_16_gpio_set_multiple(struct gpio_chip *chip,
 	unsigned long *mask, unsigned long *bits)
 {
 	struct idio_16_gpio *const idio16gpio = gpiochip_get_data(chip);
 	unsigned long flags;
 	unsigned int out_state;

 	spin_lock_irqsave(&idio16gpio->lock, flags);

 	/* process output lines 0-7 */
 	if (*mask & 0xFF) {
 		out_state = ioread8(&idio16gpio->reg->out0_7) & ~*mask;
 		out_state |= *mask & *bits;
 		iowrite8(out_state, &idio16gpio->reg->out0_7);
 	}

 	/* shift to next output line word */
 	*mask >>= 8;

 	/* process output lines 8-15 */
 	if (*mask & 0xFF) {
 		*bits >>= 8;
 		out_state = ioread8(&idio16gpio->reg->out8_15) & ~*mask;
 		out_state |= *mask & *bits;
 		iowrite8(out_state, &idio16gpio->reg->out8_15);
 	}

 	spin_unlock_irqrestore(&idio16gpio->lock, flags);
 }

 static void idio_16_irq_ack(struct irq_data *data)
 {
 }

 static void idio_16_irq_mask(struct irq_data *data)
 {
 	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
 	struct idio_16_gpio *const idio16gpio = gpiochip_get_data(chip);
 	const unsigned long mask = BIT(irqd_to_hwirq(data));
 	unsigned long flags;

 	idio16gpio->irq_mask &= ~mask;

 	if (!idio16gpio->irq_mask) {
 		spin_lock_irqsave(&idio16gpio->lock, flags);

 		iowrite8(0, &idio16gpio->reg->irq_ctl);

 		spin_unlock_irqrestore(&idio16gpio->lock, flags);
 	}
 }

 static void idio_16_irq_unmask(struct irq_data *data)
 {
 	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
 	struct idio_16_gpio *const idio16gpio = gpiochip_get_data(chip);
 	const unsigned long mask = BIT(irqd_to_hwirq(data));
 	const unsigned long prev_irq_mask = idio16gpio->irq_mask;
 	unsigned long flags;

 	idio16gpio->irq_mask |= mask;

 	if (!prev_irq_mask) {
 		spin_lock_irqsave(&idio16gpio->lock, flags);

 		ioread8(&idio16gpio->reg->irq_ctl);

 		spin_unlock_irqrestore(&idio16gpio->lock, flags);
 	}
 }

 static int idio_16_irq_set_type(struct irq_data *data, unsigned int flow_type)
 {
 	/* The only valid irq types are none and both-edges */
 	if (flow_type != IRQ_TYPE_NONE &&
 		(flow_type & IRQ_TYPE_EDGE_BOTH) != IRQ_TYPE_EDGE_BOTH)
 		return -EINVAL;

 	return 0;
 }

 static struct irq_chip idio_16_irqchip = {
 	.name = "pci-idio-16",
 	.irq_ack = idio_16_irq_ack,
 	.irq_mask = idio_16_irq_mask,
 	.irq_unmask = idio_16_irq_unmask,
 	.irq_set_type = idio_16_irq_set_type
 };

 static irqreturn_t idio_16_irq_handler(int irq, void *dev_id)
 {
 	struct idio_16_gpio *const idio16gpio = dev_id;
 	unsigned int irq_status;
 	struct gpio_chip *const chip = &idio16gpio->chip;
 	int gpio;

 	spin_lock(&idio16gpio->lock);

 	irq_status = ioread8(&idio16gpio->reg->irq_status);

 	spin_unlock(&idio16gpio->lock);

 	/* Make sure our device generated IRQ */
 	if (!(irq_status & 0x3) || !(irq_status & 0x4))
 		return IRQ_NONE;

 	for_each_set_bit(gpio, &idio16gpio->irq_mask, chip->ngpio)
 		generic_handle_irq(irq_find_mapping(chip->irqdomain, gpio));

 	spin_lock(&idio16gpio->lock);

 	/* Clear interrupt */
 	iowrite8(0, &idio16gpio->reg->in0_7);

 	spin_unlock(&idio16gpio->lock);

 	return IRQ_HANDLED;
 }

 #define IDIO_16_NGPIO 32
 static const char *idio_16_names[IDIO_16_NGPIO] = {
 	"OUT0", "OUT1", "OUT2", "OUT3", "OUT4", "OUT5", "OUT6", "OUT7",
 	"OUT8", "OUT9", "OUT10", "OUT11", "OUT12", "OUT13", "OUT14", "OUT15",
 	"IIN0", "IIN1", "IIN2", "IIN3", "IIN4", "IIN5", "IIN6", "IIN7",
 	"IIN8", "IIN9", "IIN10", "IIN11", "IIN12", "IIN13", "IIN14", "IIN15"
 };

 static int idio_16_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 {
 	struct device *const dev = &pdev->dev;
 	struct idio_16_gpio *idio16gpio;
 	int err;
 	const char *const name = pci_name(pdev);

 	idio16gpio = devm_kzalloc(dev, sizeof(*idio16gpio), GFP_KERNEL);
 	if (!idio16gpio)
 		return -ENOMEM;

 	err = pcim_enable_device(pdev);
 	if (err) {
 		dev_err(dev, "Failed to enable PCI device (%d)\n", err);
 		return err;
 	}

 	err = pcim_iomap_regions(pdev, 0x1, name);
 	if (err) {
 		dev_err(dev, "Unable to map PCI I/O addresses (%d)\n", err);
 		return err;
 	}

 	idio16gpio->reg = pcim_iomap_table(pdev)[0];

 	/* Deactivate input filters */
 	iowrite8(0, &idio16gpio->reg->filter_ctl);

 	idio16gpio->chip.label = name;
 	idio16gpio->chip.parent = dev;
 	idio16gpio->chip.owner = THIS_MODULE;
 	idio16gpio->chip.base = -1;
 	idio16gpio->chip.ngpio = IDIO_16_NGPIO;
 	idio16gpio->chip.names = idio_16_names;
 	idio16gpio->chip.get_direction = idio_16_gpio_get_direction;
 	idio16gpio->chip.direction_input = idio_16_gpio_direction_input;
 	idio16gpio->chip.direction_output = idio_16_gpio_direction_output;
 	idio16gpio->chip.get = idio_16_gpio_get;
 	idio16gpio->chip.set = idio_16_gpio_set;
 	idio16gpio->chip.set_multiple = idio_16_gpio_set_multiple;

 	spin_lock_init(&idio16gpio->lock);

 	err = devm_gpiochip_add_data(dev, &idio16gpio->chip, idio16gpio);
 	if (err) {
 		dev_err(dev, "GPIO registering failed (%d)\n", err);
 		return err;
 	}

 	/* Disable IRQ by default and clear any pending interrupt */
 	iowrite8(0, &idio16gpio->reg->irq_ctl);
 	iowrite8(0, &idio16gpio->reg->in0_7);

 	err = gpiochip_irqchip_add(&idio16gpio->chip, &idio_16_irqchip, 0,
 		handle_edge_irq, IRQ_TYPE_NONE);
 	if (err) {
 		dev_err(dev, "Could not add irqchip (%d)\n", err);
 		return err;
 	}

 	err = devm_request_irq(dev, pdev->irq, idio_16_irq_handler, IRQF_SHARED,
 		name, idio16gpio);
 	if (err) {
 		dev_err(dev, "IRQ handler registering failed (%d)\n", err);
 		return err;
 	}

 	return 0;
 }

 static const struct pci_device_id idio_16_pci_dev_id[] = {
 	{ PCI_DEVICE(0x494F, 0x0DC8) }, { 0 }
 };
 MODULE_DEVICE_TABLE(pci, idio_16_pci_dev_id);

 static struct pci_driver idio_16_driver = {
 	.name = "pci-idio-16",
 	.id_table = idio_16_pci_dev_id,
 	.probe = idio_16_probe
 };

 module_pci_driver(idio_16_driver);

 MODULE_AUTHOR("William Breathitt Gray <vilhelm.gray@gmail.com>");
 MODULE_DESCRIPTION("ACCES PCI-IDIO-16 GPIO driver");
 MODULE_LICENSE("GPL v2");
	/*
	* GPIO driver for the ACCES PCI-IDIO-16
	* Copyright (C) 2017 William Breathitt Gray
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License, version 2, as
	* published by the Free Software Foundation.
	*
	* 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/bitops.h>
	#include <linux/device.h>
	#include <linux/errno.h>
	#include <linux/gpio/driver.h>
	#include <linux/interrupt.h>
	#include <linux/irqdesc.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/pci.h>
	#include <linux/spinlock.h>
	#include <linux/types.h>

	/**
	* struct idio_16_gpio_reg - GPIO device registers structure
	* @out0_7: Read: FET Drive Outputs 0-7
	* Write: FET Drive Outputs 0-7
	* @in0_7: Read: Isolated Inputs 0-7
	* Write: Clear Interrupt
	* @irq_ctl: Read: Enable IRQ
	* Write: Disable IRQ
	* @filter_ctl: Read: Activate Input Filters 0-15
	* Write: Deactivate Input Filters 0-15
	* @out8_15: Read: FET Drive Outputs 8-15
	* Write: FET Drive Outputs 8-15
	* @in8_15: Read: Isolated Inputs 8-15
	* Write: Unused
	* @irq_status: Read: Interrupt status
	* Write: Unused
	*/
	struct idio_16_gpio_reg {
	u8 out0_7;
	u8 in0_7;
	u8 irq_ctl;
	u8 filter_ctl;
	u8 out8_15;
	u8 in8_15;
	u8 irq_status;
	};

	/**
	* struct idio_16_gpio - GPIO device private data structure
	* @chip: instance of the gpio_chip
	* @lock: synchronization lock to prevent I/O race conditions
	* @reg: I/O address offset for the GPIO device registers
	* @irq_mask: I/O bits affected by interrupts
	*/
	struct idio_16_gpio {
	struct gpio_chip chip;
	spinlock_t lock;
	struct idio_16_gpio_reg __iomem *reg;
	unsigned long irq_mask;
	};

	static int idio_16_gpio_get_direction(struct gpio_chip *chip,
	unsigned int offset)
	{
	if (offset > 15)
	return 1;

	return 0;
	}

	static int idio_16_gpio_direction_input(struct gpio_chip *chip,
	unsigned int offset)
	{
	return 0;
	}

	static int idio_16_gpio_direction_output(struct gpio_chip *chip,
	unsigned int offset, int value)
	{
	chip->set(chip, offset, value);
	return 0;
	}

	static int idio_16_gpio_get(struct gpio_chip *chip, unsigned int offset)
	{
	struct idio_16_gpio *const idio16gpio = gpiochip_get_data(chip);
	unsigned long mask = BIT(offset);

	if (offset < 8)
	return !!(ioread8(&idio16gpio->reg->out0_7) & mask);

	if (offset < 16)
	return !!(ioread8(&idio16gpio->reg->out8_15) & (mask >> 8));

	if (offset < 24)
	return !!(ioread8(&idio16gpio->reg->in0_7) & (mask >> 16));

	return !!(ioread8(&idio16gpio->reg->in8_15) & (mask >> 24));
	}

	static void idio_16_gpio_set(struct gpio_chip *chip, unsigned int offset,
	int value)
	{
	struct idio_16_gpio *const idio16gpio = gpiochip_get_data(chip);
	unsigned int mask = BIT(offset);
	void __iomem *base;
	unsigned long flags;
	unsigned int out_state;

	if (offset > 15)
	return;

	if (offset > 7) {
	mask >>= 8;
	base = &idio16gpio->reg->out8_15;
	} else
	base = &idio16gpio->reg->out0_7;

	spin_lock_irqsave(&idio16gpio->lock, flags);

	if (value)
	out_state = ioread8(base) \| mask;
	else
	out_state = ioread8(base) & ~mask;

	iowrite8(out_state, base);

	spin_unlock_irqrestore(&idio16gpio->lock, flags);
	}

	static void idio_16_gpio_set_multiple(struct gpio_chip *chip,
	unsigned long mask, unsigned long bits)
	{
	struct idio_16_gpio *const idio16gpio = gpiochip_get_data(chip);
	unsigned long flags;
	unsigned int out_state;

	spin_lock_irqsave(&idio16gpio->lock, flags);

	/* process output lines 0-7 */
	if (*mask & 0xFF) {
	out_state = ioread8(&idio16gpio->reg->out0_7) & ~*mask;
	out_state \|= mask & bits;
	iowrite8(out_state, &idio16gpio->reg->out0_7);
	}

	/* shift to next output line word */
	*mask >>= 8;

	/* process output lines 8-15 */
	if (*mask & 0xFF) {
	*bits >>= 8;
	out_state = ioread8(&idio16gpio->reg->out8_15) & ~*mask;
	out_state \|= mask & bits;
	iowrite8(out_state, &idio16gpio->reg->out8_15);
	}

	spin_unlock_irqrestore(&idio16gpio->lock, flags);
	}

	static void idio_16_irq_ack(struct irq_data *data)
	{
	}

	static void idio_16_irq_mask(struct irq_data *data)
	{
	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
	struct idio_16_gpio *const idio16gpio = gpiochip_get_data(chip);
	const unsigned long mask = BIT(irqd_to_hwirq(data));
	unsigned long flags;

	idio16gpio->irq_mask &= ~mask;

	if (!idio16gpio->irq_mask) {
	spin_lock_irqsave(&idio16gpio->lock, flags);

	iowrite8(0, &idio16gpio->reg->irq_ctl);

	spin_unlock_irqrestore(&idio16gpio->lock, flags);
	}
	}

	static void idio_16_irq_unmask(struct irq_data *data)
	{
	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
	struct idio_16_gpio *const idio16gpio = gpiochip_get_data(chip);
	const unsigned long mask = BIT(irqd_to_hwirq(data));
	const unsigned long prev_irq_mask = idio16gpio->irq_mask;
	unsigned long flags;

	idio16gpio->irq_mask \|= mask;

	if (!prev_irq_mask) {
	spin_lock_irqsave(&idio16gpio->lock, flags);

	ioread8(&idio16gpio->reg->irq_ctl);

	spin_unlock_irqrestore(&idio16gpio->lock, flags);
	}
	}

	static int idio_16_irq_set_type(struct irq_data *data, unsigned int flow_type)
	{
	/* The only valid irq types are none and both-edges */
	if (flow_type != IRQ_TYPE_NONE &&
	(flow_type & IRQ_TYPE_EDGE_BOTH) != IRQ_TYPE_EDGE_BOTH)
	return -EINVAL;

	return 0;
	}

	static struct irq_chip idio_16_irqchip = {
	.name = "pci-idio-16",
	.irq_ack = idio_16_irq_ack,
	.irq_mask = idio_16_irq_mask,
	.irq_unmask = idio_16_irq_unmask,
	.irq_set_type = idio_16_irq_set_type
	};

	static irqreturn_t idio_16_irq_handler(int irq, void *dev_id)
	{
	struct idio_16_gpio *const idio16gpio = dev_id;
	unsigned int irq_status;
	struct gpio_chip *const chip = &idio16gpio->chip;
	int gpio;

	spin_lock(&idio16gpio->lock);

	irq_status = ioread8(&idio16gpio->reg->irq_status);

	spin_unlock(&idio16gpio->lock);

	/* Make sure our device generated IRQ */
	if (!(irq_status & 0x3) \|\| !(irq_status & 0x4))
	return IRQ_NONE;

	for_each_set_bit(gpio, &idio16gpio->irq_mask, chip->ngpio)
	generic_handle_irq(irq_find_mapping(chip->irqdomain, gpio));

	spin_lock(&idio16gpio->lock);

	/* Clear interrupt */
	iowrite8(0, &idio16gpio->reg->in0_7);

	spin_unlock(&idio16gpio->lock);

	return IRQ_HANDLED;
	}

	#define IDIO_16_NGPIO 32
	static const char *idio_16_names[IDIO_16_NGPIO] = {
	"OUT0", "OUT1", "OUT2", "OUT3", "OUT4", "OUT5", "OUT6", "OUT7",
	"OUT8", "OUT9", "OUT10", "OUT11", "OUT12", "OUT13", "OUT14", "OUT15",
	"IIN0", "IIN1", "IIN2", "IIN3", "IIN4", "IIN5", "IIN6", "IIN7",
	"IIN8", "IIN9", "IIN10", "IIN11", "IIN12", "IIN13", "IIN14", "IIN15"
	};

	static int idio_16_probe(struct pci_dev pdev, const struct pci_device_id id)
	{
	struct device *const dev = &pdev->dev;
	struct idio_16_gpio *idio16gpio;
	int err;
	const char *const name = pci_name(pdev);

	idio16gpio = devm_kzalloc(dev, sizeof(*idio16gpio), GFP_KERNEL);
	if (!idio16gpio)
	return -ENOMEM;

	err = pcim_enable_device(pdev);
	if (err) {
	dev_err(dev, "Failed to enable PCI device (%d)\n", err);
	return err;
	}

	err = pcim_iomap_regions(pdev, 0x1, name);
	if (err) {
	dev_err(dev, "Unable to map PCI I/O addresses (%d)\n", err);
	return err;
	}

	idio16gpio->reg = pcim_iomap_table(pdev)[0];

	/* Deactivate input filters */
	iowrite8(0, &idio16gpio->reg->filter_ctl);

	idio16gpio->chip.label = name;
	idio16gpio->chip.parent = dev;
	idio16gpio->chip.owner = THIS_MODULE;
	idio16gpio->chip.base = -1;
	idio16gpio->chip.ngpio = IDIO_16_NGPIO;
	idio16gpio->chip.names = idio_16_names;
	idio16gpio->chip.get_direction = idio_16_gpio_get_direction;
	idio16gpio->chip.direction_input = idio_16_gpio_direction_input;
	idio16gpio->chip.direction_output = idio_16_gpio_direction_output;
	idio16gpio->chip.get = idio_16_gpio_get;
	idio16gpio->chip.set = idio_16_gpio_set;
	idio16gpio->chip.set_multiple = idio_16_gpio_set_multiple;

	spin_lock_init(&idio16gpio->lock);

	err = devm_gpiochip_add_data(dev, &idio16gpio->chip, idio16gpio);
	if (err) {
	dev_err(dev, "GPIO registering failed (%d)\n", err);
	return err;
	}

	/* Disable IRQ by default and clear any pending interrupt */
	iowrite8(0, &idio16gpio->reg->irq_ctl);
	iowrite8(0, &idio16gpio->reg->in0_7);

	err = gpiochip_irqchip_add(&idio16gpio->chip, &idio_16_irqchip, 0,
	handle_edge_irq, IRQ_TYPE_NONE);
	if (err) {
	dev_err(dev, "Could not add irqchip (%d)\n", err);
	return err;
	}

	err = devm_request_irq(dev, pdev->irq, idio_16_irq_handler, IRQF_SHARED,
	name, idio16gpio);
	if (err) {
	dev_err(dev, "IRQ handler registering failed (%d)\n", err);
	return err;
	}

	return 0;
	}

	static const struct pci_device_id idio_16_pci_dev_id[] = {
	{ PCI_DEVICE(0x494F, 0x0DC8) }, { 0 }
	};
	MODULE_DEVICE_TABLE(pci, idio_16_pci_dev_id);

	static struct pci_driver idio_16_driver = {
	.name = "pci-idio-16",
	.id_table = idio_16_pci_dev_id,
	.probe = idio_16_probe
	};

	module_pci_driver(idio_16_driver);

	MODULE_AUTHOR("William Breathitt Gray <vilhelm.gray@gmail.com>");
	MODULE_DESCRIPTION("ACCES PCI-IDIO-16 GPIO driver");
	MODULE_LICENSE("GPL v2");