text: /*
   * phy-brcm-usb.c - Broadcom USB Phy Driver
   *
   * Copyright (C) 2015-2017 Broadcom
   *
   * This software is licensed under the terms of the GNU General Public
   * License version 2, as published by the Free Software Foundation, and
   * may be copied, distributed, and modified under those terms.
   *
   * 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/clk.h>
  #include <linux/delay.h>
  #include <linux/err.h>
  #include <linux/io.h>
  #include <linux/module.h>
  #include <linux/of.h>
  #include <linux/phy/phy.h>
  #include <linux/platform_device.h>
  #include <linux/interrupt.h>
  #include <linux/soc/brcmstb/brcmstb.h>
  #include <dt-bindings/phy/phy.h>
  
  #include "phy-brcm-usb-init.h"
  
  static DEFINE_MUTEX(sysfs_lock);
  
  enum brcm_usb_phy_id {
  	BRCM_USB_PHY_2_0 = 0,
  	BRCM_USB_PHY_3_0,
  	BRCM_USB_PHY_ID_MAX
  };
  
  struct value_to_name_map {
  	int value;
  	const char *name;
  };
  
  static struct value_to_name_map brcm_dr_mode_to_name[] = {
  	{ USB_CTLR_MODE_HOST, "host" },
  	{ USB_CTLR_MODE_DEVICE, "peripheral" },
  	{ USB_CTLR_MODE_DRD, "drd" },
  	{ USB_CTLR_MODE_TYPEC_PD, "typec-pd" }
  };
  
  static struct value_to_name_map brcm_dual_mode_to_name[] = {
  	{ 0, "host" },
  	{ 1, "device" },
  	{ 2, "auto" },
  };
  
  struct brcm_usb_phy {
  	struct phy *phy;
  	unsigned int id;
  	bool inited;
  };
  
  struct brcm_usb_phy_data {
  	struct  brcm_usb_init_params ini;
  	bool			has_eohci;
  	bool			has_xhci;
  	struct clk		*usb_20_clk;
  	struct clk		*usb_30_clk;
  	struct mutex		mutex;	/* serialize phy init */
  	int			init_count;
  	struct brcm_usb_phy	phys[BRCM_USB_PHY_ID_MAX];
  };
  
  static int brcm_usb_phy_init(struct phy *gphy)
  {
  	struct brcm_usb_phy *phy = phy_get_drvdata(gphy);
  	struct brcm_usb_phy_data *priv =
  		container_of(phy, struct brcm_usb_phy_data, phys[phy->id]);
  
  	/*
  	 * Use a lock to make sure a second caller waits until
  	 * the base phy is inited before using it.
  	 */
  	mutex_lock(&priv->mutex);
  	if (priv->init_count++ == 0) {
  		clk_enable(priv->usb_20_clk);
  		clk_enable(priv->usb_30_clk);
  		brcm_usb_init_common(&priv->ini);
  	}
  	mutex_unlock(&priv->mutex);
  	if (phy->id == BRCM_USB_PHY_2_0)
  		brcm_usb_init_eohci(&priv->ini);
  	else if (phy->id == BRCM_USB_PHY_3_0)
  		brcm_usb_init_xhci(&priv->ini);
  	phy->inited = true;
  	dev_dbg(&gphy->dev, "INIT, id: %d, total: %d\n", phy->id,
  		priv->init_count);
  
  	return 0;
  }
  
  static int brcm_usb_phy_exit(struct phy *gphy)
  {
  	struct brcm_usb_phy *phy = phy_get_drvdata(gphy);
  	struct brcm_usb_phy_data *priv =
  		container_of(phy, struct brcm_usb_phy_data, phys[phy->id]);
  
  	dev_dbg(&gphy->dev, "EXIT\n");
  	if (phy->id == BRCM_USB_PHY_2_0)
  		brcm_usb_uninit_eohci(&priv->ini);
  	if (phy->id == BRCM_USB_PHY_3_0)
  		brcm_usb_uninit_xhci(&priv->ini);
  
  	/* If both xhci and eohci are gone, reset everything else */
  	mutex_lock(&priv->mutex);
  	if (--priv->init_count == 0) {
  		brcm_usb_uninit_common(&priv->ini);
  		clk_disable(priv->usb_20_clk);
  		clk_disable(priv->usb_30_clk);
  	}
  	mutex_unlock(&priv->mutex);
  	phy->inited = false;
  	return 0;
  }
  
  static struct phy_ops brcm_usb_phy_ops = {
  	.init		= brcm_usb_phy_init,
  	.exit		= brcm_usb_phy_exit,
  	.owner		= THIS_MODULE,
  };
  
  static struct phy *brcm_usb_phy_xlate(struct device *dev,
  				      struct of_phandle_args *args)
  {
  	struct brcm_usb_phy_data *data = dev_get_drvdata(dev);
  
  	/*
  	 * values 0 and 1 are for backward compatibility with
  	 * device tree nodes from older bootloaders.
  	 */
  	switch (args->args[0]) {
  	case 0:
  	case PHY_TYPE_USB2:
  		if (data->phys[BRCM_USB_PHY_2_0].phy)
  			return data->phys[BRCM_USB_PHY_2_0].phy;
  		dev_warn(dev, "Error, 2.0 Phy not found\n");
  		break;
  	case 1:
  	case PHY_TYPE_USB3:
  		if (data->phys[BRCM_USB_PHY_3_0].phy)
  			return data->phys[BRCM_USB_PHY_3_0].phy;
  		dev_warn(dev, "Error, 3.0 Phy not found\n");
  		break;
  	}
  	return ERR_PTR(-ENODEV);
  }
  
  static int name_to_value(struct value_to_name_map *table, int count,
  			 const char *name, int *value)
  {
  	int x;
  
  	*value = 0;
  	for (x = 0; x < count; x++) {
  		if (sysfs_streq(name, table[x].name)) {
  			*value = x;
  			return 0;
  		}
  	}
  	return -EINVAL;
  }
  
  static const char *value_to_name(struct value_to_name_map *table, int count,
  				 int value)
  {
  	if (value >= count)
  		return "unknown";
  	return table[value].name;
  }
  
  static ssize_t dr_mode_show(struct device *dev,
  			    struct device_attribute *attr,
  			    char *buf)
  {
  	struct brcm_usb_phy_data *priv = dev_get_drvdata(dev);
  
  	return sprintf(buf, "%s\n",
  		value_to_name(&brcm_dr_mode_to_name[0],
  			      ARRAY_SIZE(brcm_dr_mode_to_name),
  			      priv->ini.mode));
  }
  static DEVICE_ATTR_RO(dr_mode);
  
  static ssize_t dual_select_store(struct device *dev,
  				 struct device_attribute *attr,
  				 const char *buf, size_t len)
  {
  	struct brcm_usb_phy_data *priv = dev_get_drvdata(dev);
  	int value;
  	int res;
  
  	mutex_lock(&sysfs_lock);
  	res = name_to_value(&brcm_dual_mode_to_name[0],
  			    ARRAY_SIZE(brcm_dual_mode_to_name), buf, &value);
  	if (!res) {
  		brcm_usb_init_set_dual_select(&priv->ini, value);
  		res = len;
  	}
  	mutex_unlock(&sysfs_lock);
  	return res;
  }
  
  static ssize_t dual_select_show(struct device *dev,
  				struct device_attribute *attr,
  				char *buf)
  {
  	struct brcm_usb_phy_data *priv = dev_get_drvdata(dev);
  	int value;
  
  	mutex_lock(&sysfs_lock);
  	value = brcm_usb_init_get_dual_select(&priv->ini);
  	mutex_unlock(&sysfs_lock);
  	return sprintf(buf, "%s\n",
  		value_to_name(&brcm_dual_mode_to_name[0],
  			      ARRAY_SIZE(brcm_dual_mode_to_name),
  			      value));
  }
  static DEVICE_ATTR_RW(dual_select);
  
  static struct attribute *brcm_usb_phy_attrs[] = {
  	&dev_attr_dr_mode.attr,
  	&dev_attr_dual_select.attr,
  	NULL
  };
  
  static const struct attribute_group brcm_usb_phy_group = {
  	.attrs = brcm_usb_phy_attrs,
  };
  
  static int brcm_usb_phy_dvr_init(struct device *dev,
  				 struct brcm_usb_phy_data *priv,
  				 struct device_node *dn)
  {
  	struct phy *gphy;
  	int err;
  
  	priv->usb_20_clk = of_clk_get_by_name(dn, "sw_usb");
  	if (IS_ERR(priv->usb_20_clk)) {
  		dev_info(dev, "Clock not found in Device Tree\n");
  		priv->usb_20_clk = NULL;
  	}
  	err = clk_prepare_enable(priv->usb_20_clk);
  	if (err)
  		return err;
  
  	if (priv->has_eohci) {
  		gphy = devm_phy_create(dev, NULL, &brcm_usb_phy_ops);
  		if (IS_ERR(gphy)) {
  			dev_err(dev, "failed to create EHCI/OHCI PHY\n");
  			return PTR_ERR(gphy);
  		}
  		priv->phys[BRCM_USB_PHY_2_0].phy = gphy;
  		priv->phys[BRCM_USB_PHY_2_0].id = BRCM_USB_PHY_2_0;
  		phy_set_drvdata(gphy, &priv->phys[BRCM_USB_PHY_2_0]);
  	}
  
  	if (priv->has_xhci) {
  		gphy = devm_phy_create(dev, NULL, &brcm_usb_phy_ops);
  		if (IS_ERR(gphy)) {
  			dev_err(dev, "failed to create XHCI PHY\n");
  			return PTR_ERR(gphy);
  		}
  		priv->phys[BRCM_USB_PHY_3_0].phy = gphy;
  		priv->phys[BRCM_USB_PHY_3_0].id = BRCM_USB_PHY_3_0;
  		phy_set_drvdata(gphy, &priv->phys[BRCM_USB_PHY_3_0]);
  
  		priv->usb_30_clk = of_clk_get_by_name(dn, "sw_usb3");
  		if (IS_ERR(priv->usb_30_clk)) {
  			dev_info(dev,
  				 "USB3.0 clock not found in Device Tree\n");
  			priv->usb_30_clk = NULL;
  		}
  		err = clk_prepare_enable(priv->usb_30_clk);
  		if (err)
  			return err;
  	}
  	return 0;
  }
  
  static int brcm_usb_phy_probe(struct platform_device *pdev)
  {
  	struct resource *res;
  	struct device *dev = &pdev->dev;
  	struct brcm_usb_phy_data *priv;
  	struct phy_provider *phy_provider;
  	struct device_node *dn = pdev->dev.of_node;
  	int err;
  	const char *mode;
  
  	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
  	if (!priv)
  		return -ENOMEM;
  	platform_set_drvdata(pdev, priv);
  
  	priv->ini.family_id = brcmstb_get_family_id();
  	priv->ini.product_id = brcmstb_get_product_id();
  	brcm_usb_set_family_map(&priv->ini);
  	dev_dbg(dev, "Best mapping table is for %s\n",
  		priv->ini.family_name);
  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  	if (!res) {
  		dev_err(dev, "can't get USB_CTRL base address\n");
  		return -EINVAL;
  	}
  	priv->ini.ctrl_regs = devm_ioremap_resource(dev, res);
  	if (IS_ERR(priv->ini.ctrl_regs)) {
  		dev_err(dev, "can't map CTRL register space\n");
  		return -EINVAL;
  	}
  
  	/* The XHCI EC registers are optional */
  	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
  	if (res) {
  		priv->ini.xhci_ec_regs =
  			devm_ioremap_resource(dev, res);
  		if (IS_ERR(priv->ini.xhci_ec_regs)) {
  			dev_err(dev, "can't map XHCI EC register space\n");
  			return -EINVAL;
  		}
  	}
  
  	of_property_read_u32(dn, "brcm,ipp", &priv->ini.ipp);
  	of_property_read_u32(dn, "brcm,ioc", &priv->ini.ioc);
  
  	priv->ini.mode = USB_CTLR_MODE_HOST;
  	err = of_property_read_string(dn, "dr_mode", &mode);
  	if (err == 0) {
  		name_to_value(&brcm_dr_mode_to_name[0],
  			      ARRAY_SIZE(brcm_dr_mode_to_name),
  			mode, &priv->ini.mode);
  	}
  	if (of_property_read_bool(dn, "brcm,has-xhci"))
  		priv->has_xhci = true;
  	if (of_property_read_bool(dn, "brcm,has-eohci"))
  		priv->has_eohci = true;
  
  	err = brcm_usb_phy_dvr_init(dev, priv, dn);
  	if (err)
  		return err;
  
  	mutex_init(&priv->mutex);
  
  	/* make sure invert settings are correct */
  	brcm_usb_init_ipp(&priv->ini);
  
  	/*
  	 * Create sysfs entries for mode.
  	 * Remove "dual_select" attribute if not in dual mode
  	 */
  	if (priv->ini.mode != USB_CTLR_MODE_DRD)
  		brcm_usb_phy_attrs[1] = NULL;
  	err = sysfs_create_group(&dev->kobj, &brcm_usb_phy_group);
  	if (err)
  		dev_warn(dev, "Error creating sysfs attributes\n");
  
  	/* start with everything off */
  	if (priv->has_xhci)
  		brcm_usb_uninit_xhci(&priv->ini);
  	if (priv->has_eohci)
  		brcm_usb_uninit_eohci(&priv->ini);
  	brcm_usb_uninit_common(&priv->ini);
  	clk_disable(priv->usb_20_clk);
  	clk_disable(priv->usb_30_clk);
  
  	phy_provider = devm_of_phy_provider_register(dev, brcm_usb_phy_xlate);
  	if (IS_ERR(phy_provider))
  		return PTR_ERR(phy_provider);
  
  	return 0;
  }
  
  #ifdef CONFIG_PM_SLEEP
  static int brcm_usb_phy_suspend(struct device *dev)
  {
  	struct brcm_usb_phy_data *priv = dev_get_drvdata(dev);
  
  	if (priv->init_count) {
  		clk_disable(priv->usb_20_clk);
  		clk_disable(priv->usb_30_clk);
  	}
  	return 0;
  }
  
  static int brcm_usb_phy_resume(struct device *dev)
  {
  	struct brcm_usb_phy_data *priv = dev_get_drvdata(dev);
  
  	clk_enable(priv->usb_20_clk);
  	clk_enable(priv->usb_30_clk);
  	brcm_usb_init_ipp(&priv->ini);
  
  	/*
  	 * Initialize anything that was previously initialized.
  	 * Uninitialize anything that wasn't previously initialized.
  	 */
  	if (priv->init_count) {
  		brcm_usb_init_common(&priv->ini);
  		if (priv->phys[BRCM_USB_PHY_2_0].inited) {
  			brcm_usb_init_eohci(&priv->ini);
  		} else if (priv->has_eohci) {
  			brcm_usb_uninit_eohci(&priv->ini);
  			clk_disable(priv->usb_20_clk);
  		}
  		if (priv->phys[BRCM_USB_PHY_3_0].inited) {
  			brcm_usb_init_xhci(&priv->ini);
  		} else if (priv->has_xhci) {
  			brcm_usb_uninit_xhci(&priv->ini);
  			clk_disable(priv->usb_30_clk);
  		}
  	} else {
  		if (priv->has_xhci)
  			brcm_usb_uninit_xhci(&priv->ini);
  		if (priv->has_eohci)
  			brcm_usb_uninit_eohci(&priv->ini);
  		brcm_usb_uninit_common(&priv->ini);
  		clk_disable(priv->usb_20_clk);
  		clk_disable(priv->usb_30_clk);
  	}
  
  	return 0;
  }
  #endif /* CONFIG_PM_SLEEP */
  
  static const struct dev_pm_ops brcm_usb_phy_pm_ops = {
  	SET_LATE_SYSTEM_SLEEP_PM_OPS(brcm_usb_phy_suspend, brcm_usb_phy_resume)
  };
  
  static const struct of_device_id brcm_usb_dt_ids[] = {
  	{ .compatible = "brcm,brcmstb-usb-phy" },
  	{ /* sentinel */ }
  };
  
  MODULE_DEVICE_TABLE(of, brcm_usb_dt_ids);
  
  static struct platform_driver brcm_usb_driver = {
  	.probe		= brcm_usb_phy_probe,
  	.driver		= {
  		.name	= "brcmstb-usb-phy",
  		.owner	= THIS_MODULE,
  		.pm = &brcm_usb_phy_pm_ops,
  		.of_match_table = brcm_usb_dt_ids,
  	},
  };
  
  module_platform_driver(brcm_usb_driver);
  
  MODULE_ALIAS("platform:brcmstb-usb-phy");
  MODULE_AUTHOR("Al Cooper <acooper@broadcom.com>");
  MODULE_DESCRIPTION("BRCM USB PHY driver");
  MODULE_LICENSE("GPL v2");
  