// SPDX-License-Identifier: GPL-2.0-only

  /*
   * Intel Quark MFD PCI driver for I2C & GPIO
   *
   * Copyright(c) 2014 Intel Corporation.
   *

   * Intel Quark PCI device for I2C and GPIO controller sharing the same
   * PCI function. This PCI driver will split the 2 devices into their
   * respective drivers.
   */
  
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/pci.h>
  #include <linux/mfd/core.h>
  #include <linux/clkdev.h>
  #include <linux/clk-provider.h>
  #include <linux/dmi.h>
  #include <linux/platform_data/gpio-dwapb.h>
  #include <linux/platform_data/i2c-designware.h>
  
  /* PCI BAR for register base address */
  #define MFD_I2C_BAR		0
  #define MFD_GPIO_BAR		1

  /* ACPI _ADR value to match the child node */
  #define MFD_ACPI_MATCH_GPIO	0ULL
  #define MFD_ACPI_MATCH_I2C	1ULL

  /* The base GPIO number under GPIOLIB framework */
  #define INTEL_QUARK_MFD_GPIO_BASE	8
  
  /* The default number of South-Cluster GPIO on Quark. */
  #define INTEL_QUARK_MFD_NGPIO		8
  
  /* The DesignWare GPIO ports on Quark. */
  #define INTEL_QUARK_GPIO_NPORTS	1
  
  #define INTEL_QUARK_IORES_MEM	0
  #define INTEL_QUARK_IORES_IRQ	1
  
  #define INTEL_QUARK_I2C_CONTROLLER_CLK "i2c_designware.0"
  
  /* The Quark I2C controller source clock */
  #define INTEL_QUARK_I2C_CLK_HZ	33000000

  struct intel_quark_mfd {

  	struct device		*dev;

  	struct clk		*i2c_clk;
  	struct clk_lookup	*i2c_clk_lookup;
  };

  static const struct dmi_system_id dmi_platform_info[] = {

  	{

  		.matches = {
  			DMI_EXACT_MATCH(DMI_BOARD_NAME, "Galileo"),
  		},
  		.driver_data = (void *)100000,

  	},
  	{

  		.matches = {
  			DMI_EXACT_MATCH(DMI_BOARD_NAME, "GalileoGen2"),
  		},
  		.driver_data = (void *)400000,

  	},

  	{
  		.matches = {
  			DMI_EXACT_MATCH(DMI_BOARD_NAME, "SIMATIC IOT2000"),

  		},
  		.driver_data = (void *)400000,
  	},

  	{}

  };
  
  static struct resource intel_quark_i2c_res[] = {
  	[INTEL_QUARK_IORES_MEM] = {
  		.flags = IORESOURCE_MEM,
  	},
  	[INTEL_QUARK_IORES_IRQ] = {
  		.flags = IORESOURCE_IRQ,
  	},
  };

  static struct mfd_cell_acpi_match intel_quark_acpi_match_i2c = {
  	.adr = MFD_ACPI_MATCH_I2C,
  };

  static struct resource intel_quark_gpio_res[] = {
  	[INTEL_QUARK_IORES_MEM] = {
  		.flags = IORESOURCE_MEM,
  	},
  };

  static struct mfd_cell_acpi_match intel_quark_acpi_match_gpio = {
  	.adr = MFD_ACPI_MATCH_GPIO,
  };

  static struct mfd_cell intel_quark_mfd_cells[] = {
  	{

  		.id = MFD_GPIO_BAR,
  		.name = "gpio-dwapb",

  		.acpi_match = &intel_quark_acpi_match_gpio,

  		.num_resources = ARRAY_SIZE(intel_quark_gpio_res),
  		.resources = intel_quark_gpio_res,
  		.ignore_resource_conflicts = true,
  	},

  	{
  		.id = MFD_I2C_BAR,
  		.name = "i2c_designware",

  		.acpi_match = &intel_quark_acpi_match_i2c,

  		.num_resources = ARRAY_SIZE(intel_quark_i2c_res),
  		.resources = intel_quark_i2c_res,
  		.ignore_resource_conflicts = true,
  	},

  };
  
  static const struct pci_device_id intel_quark_mfd_ids[] = {
  	{ PCI_VDEVICE(INTEL, 0x0934), },
  	{},
  };
  MODULE_DEVICE_TABLE(pci, intel_quark_mfd_ids);

  static int intel_quark_register_i2c_clk(struct device *dev)

  {

  	struct intel_quark_mfd *quark_mfd = dev_get_drvdata(dev);

  	struct clk *i2c_clk;

  	i2c_clk = clk_register_fixed_rate(dev,

  					  INTEL_QUARK_I2C_CONTROLLER_CLK, NULL,

  					  0, INTEL_QUARK_I2C_CLK_HZ);

  	if (IS_ERR(i2c_clk))
  		return PTR_ERR(i2c_clk);

  	quark_mfd->i2c_clk = i2c_clk;

  	quark_mfd->i2c_clk_lookup = clkdev_create(i2c_clk, NULL,
  						INTEL_QUARK_I2C_CONTROLLER_CLK);

  	if (!quark_mfd->i2c_clk_lookup) {

  		clk_unregister(quark_mfd->i2c_clk);

  		dev_err(dev, "Fixed clk register failed
  ");

  		return -ENOMEM;
  	}

  	return 0;

  }

  static void intel_quark_unregister_i2c_clk(struct device *dev)

  {

  	struct intel_quark_mfd *quark_mfd = dev_get_drvdata(dev);

  	if (!quark_mfd->i2c_clk_lookup)

  		return;
  
  	clkdev_drop(quark_mfd->i2c_clk_lookup);
  	clk_unregister(quark_mfd->i2c_clk);
  }
  
  static int intel_quark_i2c_setup(struct pci_dev *pdev, struct mfd_cell *cell)
  {

  	const struct dmi_system_id *dmi_id;

  	struct dw_i2c_platform_data *pdata;
  	struct resource *res = (struct resource *)cell->resources;
  	struct device *dev = &pdev->dev;

  
  	res[INTEL_QUARK_IORES_MEM].start =
  		pci_resource_start(pdev, MFD_I2C_BAR);
  	res[INTEL_QUARK_IORES_MEM].end =
  		pci_resource_end(pdev, MFD_I2C_BAR);
  
  	res[INTEL_QUARK_IORES_IRQ].start = pdev->irq;
  	res[INTEL_QUARK_IORES_IRQ].end = pdev->irq;
  
  	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
  	if (!pdata)
  		return -ENOMEM;

  	/* Normal mode by default */
  	pdata->i2c_scl_freq = 100000;

  	dmi_id = dmi_first_match(dmi_platform_info);
  	if (dmi_id)
  		pdata->i2c_scl_freq = (uintptr_t)dmi_id->driver_data;

  
  	cell->platform_data = pdata;
  	cell->pdata_size = sizeof(*pdata);
  
  	return 0;
  }
  
  static int intel_quark_gpio_setup(struct pci_dev *pdev, struct mfd_cell *cell)
  {
  	struct dwapb_platform_data *pdata;
  	struct resource *res = (struct resource *)cell->resources;
  	struct device *dev = &pdev->dev;
  
  	res[INTEL_QUARK_IORES_MEM].start =
  		pci_resource_start(pdev, MFD_GPIO_BAR);
  	res[INTEL_QUARK_IORES_MEM].end =
  		pci_resource_end(pdev, MFD_GPIO_BAR);
  
  	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
  	if (!pdata)
  		return -ENOMEM;
  
  	/* For intel quark x1000, it has only one port: portA */
  	pdata->nports = INTEL_QUARK_GPIO_NPORTS;
  	pdata->properties = devm_kcalloc(dev, pdata->nports,
  					 sizeof(*pdata->properties),
  					 GFP_KERNEL);
  	if (!pdata->properties)
  		return -ENOMEM;
  
  	/* Set the properties for portA */

  	pdata->properties->fwnode	= NULL;

  	pdata->properties->idx		= 0;
  	pdata->properties->ngpio	= INTEL_QUARK_MFD_NGPIO;
  	pdata->properties->gpio_base	= INTEL_QUARK_MFD_GPIO_BASE;

  	pdata->properties->irq[0]	= pdev->irq;

  	pdata->properties->irq_shared	= true;
  
  	cell->platform_data = pdata;
  	cell->pdata_size = sizeof(*pdata);
  
  	return 0;
  }
  
  static int intel_quark_mfd_probe(struct pci_dev *pdev,
  				 const struct pci_device_id *id)
  {
  	struct intel_quark_mfd *quark_mfd;
  	int ret;
  
  	ret = pcim_enable_device(pdev);
  	if (ret)
  		return ret;
  
  	quark_mfd = devm_kzalloc(&pdev->dev, sizeof(*quark_mfd), GFP_KERNEL);
  	if (!quark_mfd)
  		return -ENOMEM;

  	quark_mfd->dev = &pdev->dev;

  	dev_set_drvdata(&pdev->dev, quark_mfd);

  	ret = intel_quark_register_i2c_clk(&pdev->dev);

  	if (ret)
  		return ret;

  	ret = intel_quark_i2c_setup(pdev, &intel_quark_mfd_cells[1]);

  	if (ret)

  		goto err_unregister_i2c_clk;

  	ret = intel_quark_gpio_setup(pdev, &intel_quark_mfd_cells[0]);

  	if (ret)

  		goto err_unregister_i2c_clk;

  	ret = mfd_add_devices(&pdev->dev, 0, intel_quark_mfd_cells,
  			      ARRAY_SIZE(intel_quark_mfd_cells), NULL, 0,
  			      NULL);
  	if (ret)
  		goto err_unregister_i2c_clk;
  
  	return 0;

  err_unregister_i2c_clk:

  	intel_quark_unregister_i2c_clk(&pdev->dev);

  	return ret;

  }
  
  static void intel_quark_mfd_remove(struct pci_dev *pdev)
  {

  	intel_quark_unregister_i2c_clk(&pdev->dev);

  	mfd_remove_devices(&pdev->dev);
  }
  
  static struct pci_driver intel_quark_mfd_driver = {
  	.name		= "intel_quark_mfd_i2c_gpio",
  	.id_table	= intel_quark_mfd_ids,
  	.probe		= intel_quark_mfd_probe,
  	.remove		= intel_quark_mfd_remove,
  };
  
  module_pci_driver(intel_quark_mfd_driver);
  
  MODULE_AUTHOR("Raymond Tan <raymond.tan@intel.com>");
  MODULE_DESCRIPTION("Intel Quark MFD PCI driver for I2C & GPIO");
  MODULE_LICENSE("GPL v2");