/*
   * Arizona interrupt support
   *
   * Copyright 2012 Wolfson Microelectronics plc
   *
   * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
   *
   * 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/delay.h>
  #include <linux/gpio.h>
  #include <linux/interrupt.h>
  #include <linux/irq.h>
  #include <linux/irqdomain.h>
  #include <linux/module.h>
  #include <linux/pm_runtime.h>
  #include <linux/regmap.h>
  #include <linux/regulator/consumer.h>
  #include <linux/slab.h>
  
  #include <linux/mfd/arizona/core.h>
  #include <linux/mfd/arizona/registers.h>
  
  #include "arizona.h"
  
  static int arizona_map_irq(struct arizona *arizona, int irq)
  {
  	int ret;
  
  	ret = regmap_irq_get_virq(arizona->aod_irq_chip, irq);
  	if (ret < 0)
  		ret = regmap_irq_get_virq(arizona->irq_chip, irq);
  
  	return ret;
  }
  
  int arizona_request_irq(struct arizona *arizona, int irq, char *name,
  			   irq_handler_t handler, void *data)
  {
  	irq = arizona_map_irq(arizona, irq);
  	if (irq < 0)
  		return irq;
  
  	return request_threaded_irq(irq, NULL, handler, IRQF_ONESHOT,
  				    name, data);
  }
  EXPORT_SYMBOL_GPL(arizona_request_irq);
  
  void arizona_free_irq(struct arizona *arizona, int irq, void *data)
  {
  	irq = arizona_map_irq(arizona, irq);
  	if (irq < 0)
  		return;
  
  	free_irq(irq, data);
  }
  EXPORT_SYMBOL_GPL(arizona_free_irq);
  
  int arizona_set_irq_wake(struct arizona *arizona, int irq, int on)
  {
  	irq = arizona_map_irq(arizona, irq);
  	if (irq < 0)
  		return irq;
  
  	return irq_set_irq_wake(irq, on);
  }
  EXPORT_SYMBOL_GPL(arizona_set_irq_wake);
  
  static irqreturn_t arizona_boot_done(int irq, void *data)
  {
  	struct arizona *arizona = data;
  
  	dev_dbg(arizona->dev, "Boot done
  ");
  
  	return IRQ_HANDLED;
  }
  
  static irqreturn_t arizona_ctrlif_err(int irq, void *data)
  {
  	struct arizona *arizona = data;
  
  	/*
  	 * For pretty much all potential sources a register cache sync
  	 * won't help, we've just got a software bug somewhere.
  	 */
  	dev_err(arizona->dev, "Control interface error
  ");
  
  	return IRQ_HANDLED;
  }
  
  static irqreturn_t arizona_irq_thread(int irq, void *data)
  {
  	struct arizona *arizona = data;

  	bool poll;

  	unsigned int val;

  	int ret;

  
  	ret = pm_runtime_get_sync(arizona->dev);
  	if (ret < 0) {
  		dev_err(arizona->dev, "Failed to resume device: %d
  ", ret);
  		return IRQ_NONE;
  	}

  	do {
  		poll = false;
  
  		/* Always handle the AoD domain */
  		handle_nested_irq(irq_find_mapping(arizona->virq, 0));
  
  		/*
  		 * Check if one of the main interrupts is asserted and only
  		 * check that domain if it is.
  		 */
  		ret = regmap_read(arizona->regmap, ARIZONA_IRQ_PIN_STATUS,
  				  &val);
  		if (ret == 0 && val & ARIZONA_IRQ1_STS) {
  			handle_nested_irq(irq_find_mapping(arizona->virq, 1));
  		} else if (ret != 0) {
  			dev_err(arizona->dev,
  				"Failed to read main IRQ status: %d
  ", ret);
  		}

  		/*
  		 * Poll the IRQ pin status to see if we're really done
  		 * if the interrupt controller can't do it for us.
  		 */
  		if (!arizona->pdata.irq_gpio) {
  			break;
  		} else if (arizona->pdata.irq_flags & IRQF_TRIGGER_RISING &&
  			   gpio_get_value_cansleep(arizona->pdata.irq_gpio)) {
  			poll = true;
  		} else if (arizona->pdata.irq_flags & IRQF_TRIGGER_FALLING &&
  			   !gpio_get_value_cansleep(arizona->pdata.irq_gpio)) {
  			poll = true;
  		}
  	} while (poll);

  
  	pm_runtime_mark_last_busy(arizona->dev);
  	pm_runtime_put_autosuspend(arizona->dev);
  
  	return IRQ_HANDLED;
  }
  
  static void arizona_irq_enable(struct irq_data *data)
  {
  }
  
  static void arizona_irq_disable(struct irq_data *data)
  {
  }

  static int arizona_irq_set_wake(struct irq_data *data, unsigned int on)
  {
  	struct arizona *arizona = irq_data_get_irq_chip_data(data);
  
  	return irq_set_irq_wake(arizona->irq, on);
  }

  static struct irq_chip arizona_irq_chip = {
  	.name			= "arizona",
  	.irq_disable		= arizona_irq_disable,
  	.irq_enable		= arizona_irq_enable,

  	.irq_set_wake		= arizona_irq_set_wake,

  };
  
  static int arizona_irq_map(struct irq_domain *h, unsigned int virq,
  			      irq_hw_number_t hw)
  {
  	struct regmap_irq_chip_data *data = h->host_data;
  
  	irq_set_chip_data(virq, data);

  	irq_set_chip_and_handler(virq, &arizona_irq_chip, handle_simple_irq);

  	irq_set_nested_thread(virq, 1);
  
  	/* ARM needs us to explicitly flag the IRQ as valid
  	 * and will set them noprobe when we do so. */
  #ifdef CONFIG_ARM
  	set_irq_flags(virq, IRQF_VALID);
  #else
  	irq_set_noprobe(virq);
  #endif
  
  	return 0;
  }
  
  static struct irq_domain_ops arizona_domain_ops = {
  	.map	= arizona_irq_map,
  	.xlate	= irq_domain_xlate_twocell,
  };
  
  int arizona_irq_init(struct arizona *arizona)
  {
  	int flags = IRQF_ONESHOT;
  	int ret, i;
  	const struct regmap_irq_chip *aod, *irq;

  	struct irq_data *irq_data;

  	arizona->ctrlif_error = true;

  	switch (arizona->type) {

  #ifdef CONFIG_MFD_WM5102

  	case WM5102:
  		aod = &wm5102_aod;
  		irq = &wm5102_irq;

  		arizona->ctrlif_error = false;

  		break;

  #endif

  #ifdef CONFIG_MFD_WM5110
  	case WM5110:
  		aod = &wm5110_aod;

  
  		switch (arizona->rev) {
  		case 0 ... 2:
  			irq = &wm5110_irq;
  			break;
  		default:
  			irq = &wm5110_revd_irq;
  			break;
  		}

  		arizona->ctrlif_error = false;

  		break;
  #endif

  #ifdef CONFIG_MFD_WM8997
  	case WM8997:
  		aod = &wm8997_aod;
  		irq = &wm8997_irq;

  		arizona->ctrlif_error = false;

  		break;
  #endif

  	default:
  		BUG_ON("Unknown Arizona class device" == NULL);
  		return -EINVAL;
  	}

  	/* Disable all wake sources by default */
  	regmap_write(arizona->regmap, ARIZONA_WAKE_CONTROL, 0);

  	/* Read the flags from the interrupt controller if not specified */
  	if (!arizona->pdata.irq_flags) {
  		irq_data = irq_get_irq_data(arizona->irq);
  		if (!irq_data) {
  			dev_err(arizona->dev, "Invalid IRQ: %d
  ",
  				arizona->irq);
  			return -EINVAL;
  		}
  
  		arizona->pdata.irq_flags = irqd_get_trigger_type(irq_data);
  		switch (arizona->pdata.irq_flags) {
  		case IRQF_TRIGGER_LOW:
  		case IRQF_TRIGGER_HIGH:
  		case IRQF_TRIGGER_RISING:
  		case IRQF_TRIGGER_FALLING:
  			break;
  
  		case IRQ_TYPE_NONE:
  		default:
  			/* Device default */
  			arizona->pdata.irq_flags = IRQF_TRIGGER_LOW;
  			break;
  		}
  	}

  
  	if (arizona->pdata.irq_flags & (IRQF_TRIGGER_HIGH |
  					IRQF_TRIGGER_RISING)) {

  		ret = regmap_update_bits(arizona->regmap, ARIZONA_IRQ_CTRL_1,
  					 ARIZONA_IRQ_POL, 0);
  		if (ret != 0) {
  			dev_err(arizona->dev, "Couldn't set IRQ polarity: %d
  ",
  				ret);
  			goto err;
  		}

  	}

  	flags |= arizona->pdata.irq_flags;

  	/* Allocate a virtual IRQ domain to distribute to the regmap domains */
  	arizona->virq = irq_domain_add_linear(NULL, 2, &arizona_domain_ops,
  					      arizona);
  	if (!arizona->virq) {

  		dev_err(arizona->dev, "Failed to add core IRQ domain
  ");

  		ret = -EINVAL;
  		goto err;
  	}
  
  	ret = regmap_add_irq_chip(arizona->regmap,
  				  irq_create_mapping(arizona->virq, 0),

  				  IRQF_ONESHOT, 0, aod,

  				  &arizona->aod_irq_chip);
  	if (ret != 0) {
  		dev_err(arizona->dev, "Failed to add AOD IRQs: %d
  ", ret);
  		goto err_domain;
  	}
  
  	ret = regmap_add_irq_chip(arizona->regmap,
  				  irq_create_mapping(arizona->virq, 1),

  				  IRQF_ONESHOT, 0, irq,

  				  &arizona->irq_chip);
  	if (ret != 0) {

  		dev_err(arizona->dev, "Failed to add main IRQs: %d
  ", ret);

  		goto err_aod;
  	}
  
  	/* Make sure the boot done IRQ is unmasked for resumes */
  	i = arizona_map_irq(arizona, ARIZONA_IRQ_BOOT_DONE);
  	ret = request_threaded_irq(i, NULL, arizona_boot_done, IRQF_ONESHOT,
  				   "Boot done", arizona);
  	if (ret != 0) {
  		dev_err(arizona->dev, "Failed to request boot done %d: %d
  ",
  			arizona->irq, ret);
  		goto err_boot_done;
  	}
  
  	/* Handle control interface errors in the core */

  	if (arizona->ctrlif_error) {

  		i = arizona_map_irq(arizona, ARIZONA_IRQ_CTRLIF_ERR);
  		ret = request_threaded_irq(i, NULL, arizona_ctrlif_err,
  					   IRQF_ONESHOT,
  					   "Control interface error", arizona);
  		if (ret != 0) {
  			dev_err(arizona->dev,
  				"Failed to request CTRLIF_ERR %d: %d
  ",
  				arizona->irq, ret);
  			goto err_ctrlif;
  		}

  	}

  	/* Used to emulate edge trigger and to work around broken pinmux */
  	if (arizona->pdata.irq_gpio) {
  		if (gpio_to_irq(arizona->pdata.irq_gpio) != arizona->irq) {
  			dev_warn(arizona->dev, "IRQ %d is not GPIO %d (%d)
  ",
  				 arizona->irq, arizona->pdata.irq_gpio,
  				 gpio_to_irq(arizona->pdata.irq_gpio));
  			arizona->irq = gpio_to_irq(arizona->pdata.irq_gpio);
  		}
  
  		ret = devm_gpio_request_one(arizona->dev,
  					    arizona->pdata.irq_gpio,
  					    GPIOF_IN, "arizona IRQ");
  		if (ret != 0) {
  			dev_err(arizona->dev,
  				"Failed to request IRQ GPIO %d:: %d
  ",
  				arizona->pdata.irq_gpio, ret);
  			arizona->pdata.irq_gpio = 0;
  		}
  	}

  	ret = request_threaded_irq(arizona->irq, NULL, arizona_irq_thread,
  				   flags, "arizona", arizona);
  
  	if (ret != 0) {

  		dev_err(arizona->dev, "Failed to request primary IRQ %d: %d
  ",

  			arizona->irq, ret);
  		goto err_main_irq;
  	}
  
  	return 0;
  
  err_main_irq:

  	if (arizona->ctrlif_error)
  		free_irq(arizona_map_irq(arizona, ARIZONA_IRQ_CTRLIF_ERR),
  			 arizona);

  err_ctrlif:
  	free_irq(arizona_map_irq(arizona, ARIZONA_IRQ_BOOT_DONE), arizona);
  err_boot_done:
  	regmap_del_irq_chip(irq_create_mapping(arizona->virq, 1),
  			    arizona->irq_chip);
  err_aod:
  	regmap_del_irq_chip(irq_create_mapping(arizona->virq, 0),
  			    arizona->aod_irq_chip);
  err_domain:
  err:
  	return ret;
  }
  
  int arizona_irq_exit(struct arizona *arizona)
  {

  	if (arizona->ctrlif_error)
  		free_irq(arizona_map_irq(arizona, ARIZONA_IRQ_CTRLIF_ERR),
  			 arizona);

  	free_irq(arizona_map_irq(arizona, ARIZONA_IRQ_BOOT_DONE), arizona);
  	regmap_del_irq_chip(irq_create_mapping(arizona->virq, 1),
  			    arizona->irq_chip);
  	regmap_del_irq_chip(irq_create_mapping(arizona->virq, 0),
  			    arizona->aod_irq_chip);
  	free_irq(arizona->irq, arizona);
  
  	return 0;
  }