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Commit 9caf1f22 authored by James Hogan's avatar James Hogan Committed by Linus Walleij
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gpio-tz1090: add TZ1090 gpio driver 



Add a GPIO driver for the main GPIOs found in the TZ1090 (Comet) SoC.
This doesn't include low-power GPIOs as they're controlled separately
via the Powerdown Controller (PDC) registers.

The driver is instantiated by device tree and supports interrupts for
all GPIOs.

Changes in v4:
 - fix typos in DT bindings compatible properties
 - reference Documentation/devicetree/bindings/gpio/gpio.txt in
   gpio-ranges description in DT bindings
 - fix gpio-ranges examples in DT bindings (it must now have 3 cells)
 - gpio-tz1090: use of_property_read_u32 instead of of_get_property

Changes in v3:
 - separated from irq-imgpdc and removed arch/metag changes to allow
   these patches to go upstream separately via the pinctrl[/gpio] trees
   (particularly the pinctrl drivers depend on the new pinconf DT
   bindings).
 - some s/unsigned/unsigned int/.
 - some s/unsigned int/bool/ and use of BIT().
 - gpio-tz1090*: refer to <dt-bindings/gpio/gpio.h> and
   <dt-bindings/interrupt-controller/irq.h> flags in bindings.
 - gpio-tz1090*: move initcall from postcore to subsys.
 - gpio-tz1090: add REG_ prefix to some constants for consistency.
 - gpio-tz1090: add comment to explain tz1090_gpio_irq_next_edge
   cunningness.

Changes in v2:
 - gpio-tz1090: remove references to Linux flags in dt bindings
 - gpio-tz1090: make use of BIT() from linux/bitops.h
 - gpio-tz1090: make register accessors inline to match pinctrl
 - gpio-tz1090: update gpio-ranges to use 3 cells after recent ABI
   breakage

Signed-off-by: default avatarJames Hogan <james.hogan@imgtec.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Rob Landley <rob@landley.net>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: linux-doc@vger.kernel.org
Cc: devicetree-discuss@lists.ozlabs.org
Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
parent ad81f054

Documentation/devicetree/bindings/gpio/gpio-tz1090.txt

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ImgTec TZ1090 GPIO Controller



Required properties:

- compatible: Compatible property value should be "img,tz1090-gpio".



- reg: Physical base address of the controller and length of memory mapped

  region.



- #address-cells: Should be 1 (for bank subnodes)



- #size-cells: Should be 0 (for bank subnodes)



- Each bank of GPIOs should have a subnode to represent it.



  Bank subnode required properties:

  - reg: Index of bank in the range 0 to 2.



  - gpio-controller: Specifies that the node is a gpio controller.



  - #gpio-cells: Should be 2. The syntax of the gpio specifier used by client

    nodes should have the following values.

       <[phandle of the gpio controller node]

        [gpio number within the gpio bank]

        [gpio flags]>



    Values for gpio specifier:

    - GPIO number: a value in the range 0 to 29.

    - GPIO flags: bit field of flags, as defined in <dt-bindings/gpio/gpio.h>.

      Only the following flags are supported:

        GPIO_ACTIVE_HIGH

        GPIO_ACTIVE_LOW



  Bank subnode optional properties:

  - gpio-ranges: Mapping to pin controller pins (as described in

    Documentation/devicetree/bindings/gpio/gpio.txt)



  - interrupts: Interrupt for the entire bank



  - interrupt-controller: Specifies that the node is an interrupt controller



  - #interrupt-cells: Should be 2. The syntax of the interrupt specifier used by

    client nodes should have the following values.

       <[phandle of the interurupt controller]

        [gpio number within the gpio bank]

        [irq flags]>



    Values for irq specifier:

    - GPIO number: a value in the range 0 to 29

    - IRQ flags: value to describe edge and level triggering, as defined in

      <dt-bindings/interrupt-controller/irq.h>. Only the following flags are

      supported:

        IRQ_TYPE_EDGE_RISING

        IRQ_TYPE_EDGE_FALLING

        IRQ_TYPE_EDGE_BOTH

        IRQ_TYPE_LEVEL_HIGH

        IRQ_TYPE_LEVEL_LOW







Example:



	gpios: gpio-controller@02005800 {

		#address-cells = <1>;

		#size-cells = <0>;

		compatible = "img,tz1090-gpio";

		reg = <0x02005800 0x90>;



		/* bank 0 with an interrupt */

		gpios0: bank@0 {

			#gpio-cells = <2>;

			#interrupt-cells = <2>;

			reg = <0>;

			interrupts = <13 IRQ_TYPE_LEVEL_HIGH>;

			gpio-controller;

			gpio-ranges = <&pinctrl 0 0 30>;

			interrupt-controller;

		};



		/* bank 2 without interrupt */

		gpios2: bank@2 {

			#gpio-cells = <2>;

			reg = <2>;

			gpio-controller;

			gpio-ranges = <&pinctrl 0 60 30>;

		};

	};

drivers/gpio/Kconfig

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@@ -242,6 +242,13 @@ config GPIO_TS5500 
	  blocks of the TS-5500: DIO1, DIO2 and the LCD port, and the TS-5600

	  LCD port.



config GPIO_TZ1090

	bool "Toumaz Xenif TZ1090 GPIO support"

	depends on SOC_TZ1090

	default y

	help

	  Say yes here to support Toumaz Xenif TZ1090 GPIOs.



config GPIO_XILINX

	bool "Xilinx GPIO support"

	depends on PPC_OF || MICROBLAZE || ARCH_ZYNQ

drivers/gpio/Makefile

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@@ -79,6 +79,7 @@ obj-$(CONFIG_GPIO_TPS65912) += gpio-tps65912.o 
obj-$(CONFIG_GPIO_TS5500)	+= gpio-ts5500.o

obj-$(CONFIG_GPIO_TWL4030)	+= gpio-twl4030.o

obj-$(CONFIG_GPIO_TWL6040)	+= gpio-twl6040.o

obj-$(CONFIG_GPIO_TZ1090)	+= gpio-tz1090.o

obj-$(CONFIG_GPIO_UCB1400)	+= gpio-ucb1400.o

obj-$(CONFIG_GPIO_VIPERBOARD)	+= gpio-viperboard.o

obj-$(CONFIG_GPIO_VR41XX)	+= gpio-vr41xx.o

drivers/gpio/gpio-tz1090.c

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/*

 * Toumaz Xenif TZ1090 GPIO handling.

 *

 * Copyright (C) 2008-2013 Imagination Technologies Ltd.

 *

 *  Based on ARM PXA code and others.

 *

 * 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.

 */



#include <linux/bitops.h>

#include <linux/export.h>

#include <linux/gpio.h>

#include <linux/interrupt.h>

#include <linux/io.h>

#include <linux/irq.h>

#include <linux/irqdomain.h>

#include <linux/kernel.h>

#include <linux/of_irq.h>

#include <linux/pinctrl/consumer.h>

#include <linux/platform_device.h>

#include <linux/slab.h>

#include <linux/syscore_ops.h>

#include <asm/global_lock.h>



/* Register offsets from bank base address */

#define REG_GPIO_DIR		0x00

#define REG_GPIO_IRQ_PLRT	0x20

#define REG_GPIO_IRQ_TYPE	0x30

#define REG_GPIO_IRQ_EN		0x40

#define REG_GPIO_IRQ_STS	0x50

#define REG_GPIO_BIT_EN		0x60

#define REG_GPIO_DIN		0x70

#define REG_GPIO_DOUT		0x80



/* REG_GPIO_IRQ_PLRT */

#define REG_GPIO_IRQ_PLRT_LOW	0

#define REG_GPIO_IRQ_PLRT_HIGH	1



/* REG_GPIO_IRQ_TYPE */

#define REG_GPIO_IRQ_TYPE_LEVEL	0

#define REG_GPIO_IRQ_TYPE_EDGE	1



/**

 * struct tz1090_gpio_bank - GPIO bank private data

 * @chip:	Generic GPIO chip for GPIO bank

 * @domain:	IRQ domain for GPIO bank (may be NULL)

 * @reg:	Base of registers, offset for this GPIO bank

 * @irq:	IRQ number for GPIO bank

 * @label:	Debug GPIO bank label, used for storage of chip->label

 *

 * This is the main private data for a GPIO bank. It encapsulates a gpio_chip,

 * and the callbacks for the gpio_chip can access the private data with the

 * to_bank() macro below.

 */

struct tz1090_gpio_bank {

	struct gpio_chip chip;

	struct irq_domain *domain;

	void __iomem *reg;

	int irq;

	char label[16];

};

#define to_bank(c)	container_of(c, struct tz1090_gpio_bank, chip)



/**

 * struct tz1090_gpio - Overall GPIO device private data

 * @dev:	Device (from platform device)

 * @reg:	Base of GPIO registers

 *

 * Represents the overall GPIO device. This structure is actually only

 * temporary, and used during init.

 */

struct tz1090_gpio {

	struct device *dev;

	void __iomem *reg;

};



/**

 * struct tz1090_gpio_bank_info - Temporary registration info for GPIO bank

 * @priv:	Overall GPIO device private data

 * @node:	Device tree node specific to this GPIO bank

 * @index:	Index of bank in range 0-2

 */

struct tz1090_gpio_bank_info {

	struct tz1090_gpio *priv;

	struct device_node *node;

	unsigned int index;

};



/* Convenience register accessors */

static inline void tz1090_gpio_write(struct tz1090_gpio_bank *bank,

			      unsigned int reg_offs, u32 data)

{

	iowrite32(data, bank->reg + reg_offs);

}



static inline u32 tz1090_gpio_read(struct tz1090_gpio_bank *bank,

			    unsigned int reg_offs)

{

	return ioread32(bank->reg + reg_offs);

}



/* caller must hold LOCK2 */

static inline void _tz1090_gpio_clear_bit(struct tz1090_gpio_bank *bank,

					  unsigned int reg_offs,

					  unsigned int offset)

{

	u32 value;



	value = tz1090_gpio_read(bank, reg_offs);

	value &= ~BIT(offset);

	tz1090_gpio_write(bank, reg_offs, value);

}



static void tz1090_gpio_clear_bit(struct tz1090_gpio_bank *bank,

				  unsigned int reg_offs,

				  unsigned int offset)

{

	int lstat;



	__global_lock2(lstat);

	_tz1090_gpio_clear_bit(bank, reg_offs, offset);

	__global_unlock2(lstat);

}



/* caller must hold LOCK2 */

static inline void _tz1090_gpio_set_bit(struct tz1090_gpio_bank *bank,

					unsigned int reg_offs,

					unsigned int offset)

{

	u32 value;



	value = tz1090_gpio_read(bank, reg_offs);

	value |= BIT(offset);

	tz1090_gpio_write(bank, reg_offs, value);

}



static void tz1090_gpio_set_bit(struct tz1090_gpio_bank *bank,

				unsigned int reg_offs,

				unsigned int offset)

{

	int lstat;



	__global_lock2(lstat);

	_tz1090_gpio_set_bit(bank, reg_offs, offset);

	__global_unlock2(lstat);

}



/* caller must hold LOCK2 */

static inline void _tz1090_gpio_mod_bit(struct tz1090_gpio_bank *bank,

					unsigned int reg_offs,

					unsigned int offset,

					bool val)

{

	u32 value;



	value = tz1090_gpio_read(bank, reg_offs);

	value &= ~BIT(offset);

	if (val)

		value |= BIT(offset);

	tz1090_gpio_write(bank, reg_offs, value);

}



static void tz1090_gpio_mod_bit(struct tz1090_gpio_bank *bank,

				unsigned int reg_offs,

				unsigned int offset,

				bool val)

{

	int lstat;



	__global_lock2(lstat);

	_tz1090_gpio_mod_bit(bank, reg_offs, offset, val);

	__global_unlock2(lstat);

}



static inline int tz1090_gpio_read_bit(struct tz1090_gpio_bank *bank,

				       unsigned int reg_offs,

				       unsigned int offset)

{

	return tz1090_gpio_read(bank, reg_offs) & BIT(offset);

}



/* GPIO chip callbacks */



static int tz1090_gpio_direction_input(struct gpio_chip *chip,

				       unsigned int offset)

{

	struct tz1090_gpio_bank *bank = to_bank(chip);

	tz1090_gpio_set_bit(bank, REG_GPIO_DIR, offset);



	return 0;

}



static int tz1090_gpio_direction_output(struct gpio_chip *chip,

					unsigned int offset, int output_value)

{

	struct tz1090_gpio_bank *bank = to_bank(chip);

	int lstat;



	__global_lock2(lstat);

	_tz1090_gpio_mod_bit(bank, REG_GPIO_DOUT, offset, output_value);

	_tz1090_gpio_clear_bit(bank, REG_GPIO_DIR, offset);

	__global_unlock2(lstat);



	return 0;

}



/*

 * Return GPIO level

 */

static int tz1090_gpio_get(struct gpio_chip *chip, unsigned int offset)

{

	struct tz1090_gpio_bank *bank = to_bank(chip);



	return tz1090_gpio_read_bit(bank, REG_GPIO_DIN, offset);

}



/*

 * Set output GPIO level

 */

static void tz1090_gpio_set(struct gpio_chip *chip, unsigned int offset,

			    int output_value)

{

	struct tz1090_gpio_bank *bank = to_bank(chip);



	tz1090_gpio_mod_bit(bank, REG_GPIO_DOUT, offset, output_value);

}



static int tz1090_gpio_request(struct gpio_chip *chip, unsigned int offset)

{

	struct tz1090_gpio_bank *bank = to_bank(chip);

	int ret;



	ret = pinctrl_request_gpio(chip->base + offset);

	if (ret)

		return ret;



	tz1090_gpio_set_bit(bank, REG_GPIO_DIR, offset);

	tz1090_gpio_set_bit(bank, REG_GPIO_BIT_EN, offset);



	return 0;

}



static void tz1090_gpio_free(struct gpio_chip *chip, unsigned int offset)

{

	struct tz1090_gpio_bank *bank = to_bank(chip);



	pinctrl_free_gpio(chip->base + offset);



	tz1090_gpio_clear_bit(bank, REG_GPIO_BIT_EN, offset);

}



static int tz1090_gpio_to_irq(struct gpio_chip *chip, unsigned int offset)

{

	struct tz1090_gpio_bank *bank = to_bank(chip);



	if (!bank->domain)

		return -EINVAL;



	return irq_create_mapping(bank->domain, offset);

}



/* IRQ chip handlers */



/* Get TZ1090 GPIO chip from irq data provided to generic IRQ callbacks */

static inline struct tz1090_gpio_bank *irqd_to_gpio_bank(struct irq_data *data)

{

	return (struct tz1090_gpio_bank *)data->domain->host_data;

}



static void tz1090_gpio_irq_clear(struct tz1090_gpio_bank *bank,

				  unsigned int offset)

{

	tz1090_gpio_clear_bit(bank, REG_GPIO_IRQ_STS, offset);

}



static void tz1090_gpio_irq_enable(struct tz1090_gpio_bank *bank,

				   unsigned int offset, bool enable)

{

	tz1090_gpio_mod_bit(bank, REG_GPIO_IRQ_EN, offset, enable);

}



static void tz1090_gpio_irq_polarity(struct tz1090_gpio_bank *bank,

				     unsigned int offset, unsigned int polarity)

{

	tz1090_gpio_mod_bit(bank, REG_GPIO_IRQ_PLRT, offset, polarity);

}



static int tz1090_gpio_valid_handler(struct irq_desc *desc)

{

	return desc->handle_irq == handle_level_irq ||

		desc->handle_irq == handle_edge_irq;

}



static void tz1090_gpio_irq_type(struct tz1090_gpio_bank *bank,

				 unsigned int offset, unsigned int type)

{

	tz1090_gpio_mod_bit(bank, REG_GPIO_IRQ_TYPE, offset, type);

}



/* set polarity to trigger on next edge, whether rising or falling */

static void tz1090_gpio_irq_next_edge(struct tz1090_gpio_bank *bank,

				      unsigned int offset)

{

	unsigned int value_p, value_i;

	int lstat;



	/*

	 * Set the GPIO's interrupt polarity to the opposite of the current

	 * input value so that the next edge triggers an interrupt.

	 */

	__global_lock2(lstat);

	value_i = ~tz1090_gpio_read(bank, REG_GPIO_DIN);

	value_p = tz1090_gpio_read(bank, REG_GPIO_IRQ_PLRT);

	value_p &= ~BIT(offset);

	value_p |= value_i & BIT(offset);

	tz1090_gpio_write(bank, REG_GPIO_IRQ_PLRT, value_p);

	__global_unlock2(lstat);

}



static void gpio_ack_irq(struct irq_data *data)

{

	struct tz1090_gpio_bank *bank = irqd_to_gpio_bank(data);



	tz1090_gpio_irq_clear(bank, data->hwirq);

}



static void gpio_mask_irq(struct irq_data *data)

{

	struct tz1090_gpio_bank *bank = irqd_to_gpio_bank(data);



	tz1090_gpio_irq_enable(bank, data->hwirq, false);

}



static void gpio_unmask_irq(struct irq_data *data)

{

	struct tz1090_gpio_bank *bank = irqd_to_gpio_bank(data);



	tz1090_gpio_irq_enable(bank, data->hwirq, true);

}



static unsigned int gpio_startup_irq(struct irq_data *data)

{

	struct tz1090_gpio_bank *bank = irqd_to_gpio_bank(data);

	irq_hw_number_t hw = data->hwirq;

	struct irq_desc *desc = irq_to_desc(data->irq);



	/*

	 * This warning indicates that the type of the irq hasn't been set

	 * before enabling the irq. This would normally be done by passing some

	 * trigger flags to request_irq().

	 */

	WARN(!tz1090_gpio_valid_handler(desc),

		"irq type not set before enabling gpio irq %d", data->irq);



	tz1090_gpio_irq_clear(bank, hw);

	tz1090_gpio_irq_enable(bank, hw, true);

	return 0;

}



static int gpio_set_irq_type(struct irq_data *data, unsigned int flow_type)

{

	struct tz1090_gpio_bank *bank = irqd_to_gpio_bank(data);

	unsigned int type;

	unsigned int polarity;



	switch (flow_type) {

	case IRQ_TYPE_EDGE_BOTH:

		type = REG_GPIO_IRQ_TYPE_EDGE;

		polarity = REG_GPIO_IRQ_PLRT_LOW;

		break;

	case IRQ_TYPE_EDGE_RISING:

		type = REG_GPIO_IRQ_TYPE_EDGE;

		polarity = REG_GPIO_IRQ_PLRT_HIGH;

		break;

	case IRQ_TYPE_EDGE_FALLING:

		type = REG_GPIO_IRQ_TYPE_EDGE;

		polarity = REG_GPIO_IRQ_PLRT_LOW;

		break;

	case IRQ_TYPE_LEVEL_HIGH:

		type = REG_GPIO_IRQ_TYPE_LEVEL;

		polarity = REG_GPIO_IRQ_PLRT_HIGH;

		break;

	case IRQ_TYPE_LEVEL_LOW:

		type = REG_GPIO_IRQ_TYPE_LEVEL;

		polarity = REG_GPIO_IRQ_PLRT_LOW;

		break;

	default:

		return -EINVAL;

	}



	tz1090_gpio_irq_type(bank, data->hwirq, type);

	if (type == REG_GPIO_IRQ_TYPE_LEVEL)

		__irq_set_handler_locked(data->irq, handle_level_irq);

	else

		__irq_set_handler_locked(data->irq, handle_edge_irq);



	if (flow_type == IRQ_TYPE_EDGE_BOTH)

		tz1090_gpio_irq_next_edge(bank, data->hwirq);

	else

		tz1090_gpio_irq_polarity(bank, data->hwirq, polarity);



	return 0;

}



#ifdef CONFIG_SUSPEND

static int gpio_set_irq_wake(struct irq_data *data, unsigned int on)

{

	struct tz1090_gpio_bank *bank = irqd_to_gpio_bank(data);



#ifdef CONFIG_PM_DEBUG

	pr_info("irq_wake irq%d state:%d\n", data->irq, on);

#endif



	/* wake on gpio block interrupt */

	return irq_set_irq_wake(bank->irq, on);

}

#else

#define gpio_set_irq_wake NULL

#endif



/* gpio virtual interrupt functions */

static struct irq_chip gpio_irq_chip = {

	.irq_startup	= gpio_startup_irq,

	.irq_ack	= gpio_ack_irq,

	.irq_mask	= gpio_mask_irq,

	.irq_unmask	= gpio_unmask_irq,

	.irq_set_type	= gpio_set_irq_type,

	.irq_set_wake	= gpio_set_irq_wake,

	.flags		= IRQCHIP_MASK_ON_SUSPEND,

};



static void tz1090_gpio_irq_handler(unsigned int irq, struct irq_desc *desc)

{

	irq_hw_number_t hw;

	unsigned int irq_stat, irq_no;

	struct tz1090_gpio_bank *bank;

	struct irq_desc *child_desc;



	bank = (struct tz1090_gpio_bank *)irq_desc_get_handler_data(desc);

	irq_stat = tz1090_gpio_read(bank, REG_GPIO_DIR) &

		   tz1090_gpio_read(bank, REG_GPIO_IRQ_STS) &

		   tz1090_gpio_read(bank, REG_GPIO_IRQ_EN) &

		   0x3FFFFFFF; /* 30 bits only */



	for (hw = 0; irq_stat; irq_stat >>= 1, ++hw) {

		if (!(irq_stat & 1))

			continue;



		irq_no = irq_linear_revmap(bank->domain, hw);

		child_desc = irq_to_desc(irq_no);



		/* Toggle edge for pin with both edges triggering enabled */

		if (irqd_get_trigger_type(&child_desc->irq_data)

				== IRQ_TYPE_EDGE_BOTH)

			tz1090_gpio_irq_next_edge(bank, hw);



		BUG_ON(!tz1090_gpio_valid_handler(child_desc));

		generic_handle_irq_desc(irq_no, child_desc);

	}

}



static int tz1090_gpio_irq_map(struct irq_domain *d, unsigned int irq,

			       irq_hw_number_t hw)

{

	irq_set_chip(irq, &gpio_irq_chip);

	return 0;

}



static const struct irq_domain_ops tz1090_gpio_irq_domain_ops = {

	.map	= tz1090_gpio_irq_map,

	.xlate	= irq_domain_xlate_twocell,

};



static int tz1090_gpio_bank_probe(struct tz1090_gpio_bank_info *info)

{

	struct device_node *np = info->node;

	struct device *dev = info->priv->dev;

	struct tz1090_gpio_bank *bank;



	bank = devm_kzalloc(dev, sizeof(*bank), GFP_KERNEL);

	if (!bank) {

		dev_err(dev, "unable to allocate driver data\n");

		return -ENOMEM;

	}



	/* Offset the main registers to the first register in this bank */

	bank->reg = info->priv->reg + info->index * 4;



	/* Set up GPIO chip */

	snprintf(bank->label, sizeof(bank->label), "tz1090-gpio-%u",

		 info->index);

	bank->chip.label		= bank->label;

	bank->chip.dev			= dev;

	bank->chip.direction_input	= tz1090_gpio_direction_input;

	bank->chip.direction_output	= tz1090_gpio_direction_output;

	bank->chip.get			= tz1090_gpio_get;

	bank->chip.set			= tz1090_gpio_set;

	bank->chip.free			= tz1090_gpio_free;

	bank->chip.request		= tz1090_gpio_request;

	bank->chip.to_irq		= tz1090_gpio_to_irq;

	bank->chip.of_node		= np;



	/* GPIO numbering from 0 */

	bank->chip.base			= info->index * 30;

	bank->chip.ngpio		= 30;



	/* Add the GPIO bank */

	gpiochip_add(&bank->chip);



	/* Get the GPIO bank IRQ if provided */

	bank->irq = irq_of_parse_and_map(np, 0);



	/* The interrupt is optional (it may be used by another core on chip) */

	if (bank->irq < 0) {

		dev_info(dev, "IRQ not provided for bank %u, IRQs disabled\n",

			 info->index);

		return 0;

	}



	dev_info(dev, "Setting up IRQs for GPIO bank %u\n",

		 info->index);



	/*

	 * Initialise all interrupts to disabled so we don't get

	 * spurious ones on a dirty boot and hit the BUG_ON in the

	 * handler.

	 */

	tz1090_gpio_write(bank, REG_GPIO_IRQ_EN, 0);



	/* Add a virtual IRQ for each GPIO */

	bank->domain = irq_domain_add_linear(np,

					     bank->chip.ngpio,

					     &tz1090_gpio_irq_domain_ops,

					     bank);



	/* Setup chained handler for this GPIO bank */

	irq_set_handler_data(bank->irq, bank);

	irq_set_chained_handler(bank->irq, tz1090_gpio_irq_handler);



	return 0;

}



static void tz1090_gpio_register_banks(struct tz1090_gpio *priv)

{

	struct device_node *np = priv->dev->of_node;

	struct device_node *node;



	for_each_available_child_of_node(np, node) {

		struct tz1090_gpio_bank_info info;

		u32 addr;

		int ret;



		ret = of_property_read_u32(node, "reg", &addr);

		if (ret) {

			dev_err(priv->dev, "invalid reg on %s\n",

				node->full_name);

			continue;

		}

		if (addr >= 3) {

			dev_err(priv->dev, "index %u in %s out of range\n",

				addr, node->full_name);

			continue;

		}



		info.index = addr;

		info.node = of_node_get(node);

		info.priv = priv;



		ret = tz1090_gpio_bank_probe(&info);

		if (ret) {

			dev_err(priv->dev, "failure registering %s\n",

				node->full_name);

			of_node_put(node);

			continue;

		}

	}

}



static int tz1090_gpio_probe(struct platform_device *pdev)

{

	struct device_node *np = pdev->dev.of_node;

	struct resource *res_regs;

	struct tz1090_gpio priv;



	if (!np) {

		dev_err(&pdev->dev, "must be instantiated via devicetree\n");

		return -ENOENT;

	}



	res_regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);

	if (!res_regs) {

		dev_err(&pdev->dev, "cannot find registers resource\n");

		return -ENOENT;

	}



	priv.dev = &pdev->dev;



	/* Ioremap the registers */

	priv.reg = devm_ioremap(&pdev->dev, res_regs->start,

				 res_regs->end - res_regs->start);

	if (!priv.reg) {

		dev_err(&pdev->dev, "unable to ioremap registers\n");

		return -ENOMEM;

	}



	/* Look for banks */

	tz1090_gpio_register_banks(&priv);



	return 0;

}



static struct of_device_id tz1090_gpio_of_match[] = {

	{ .compatible = "img,tz1090-gpio" },

	{ },

};



static struct platform_driver tz1090_gpio_driver = {

	.driver = {

		.name		= "tz1090-gpio",

		.owner		= THIS_MODULE,

		.of_match_table	= tz1090_gpio_of_match,

	},

	.probe		= tz1090_gpio_probe,

};



static int __init tz1090_gpio_init(void)

{

	return platform_driver_register(&tz1090_gpio_driver);

}

subsys_initcall(tz1090_gpio_init);