/*
   * host.c - ChipIdea USB host controller driver
   *
   * Copyright (c) 2012 Intel Corporation
   *
   * Author: Alexander Shishkin
   *
   * 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.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, write to the Free Software
   * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
   */
  
  #include <linux/kernel.h>
  #include <linux/io.h>
  #include <linux/usb.h>
  #include <linux/usb/hcd.h>
  #include <linux/usb/chipidea.h>
  #include <linux/regulator/consumer.h>
  #include <linux/imx_gpc.h>
  
  #include "../host/ehci.h"
  
  #include "ci.h"
  #include "bits.h"
  #include "host.h"
  
  static struct hc_driver __read_mostly ci_ehci_hc_driver;
  static int (*orig_bus_suspend)(struct usb_hcd *hcd);
  static int (*orig_bus_resume)(struct usb_hcd *hcd);
  static int (*orig_hub_control)(struct usb_hcd *hcd,
  				u16 typeReq, u16 wValue, u16 wIndex,
  				char *buf, u16 wLength);
  
  struct ehci_ci_priv {
  	struct regulator *reg_vbus;
  };
  
  /* This function is used to override WKCN, WKDN, and WKOC */
  static void ci_ehci_override_wakeup_flag(struct ehci_hcd *ehci,
  		u32 __iomem *reg, u32 flags, bool set)
  {
  	u32 val = ehci_readl(ehci, reg);
  
  	if (set)
  		val |= flags;
  	else
  		val &= ~flags;
  
  	ehci_writel(ehci, val, reg);
  }
  
  static int ehci_ci_portpower(struct usb_hcd *hcd, int portnum, bool enable)
  {
  	struct ehci_hcd *ehci = hcd_to_ehci(hcd);
  	struct ehci_ci_priv *priv = (struct ehci_ci_priv *)ehci->priv;
  	struct device *dev = hcd->self.controller;
  	int ret = 0;
  	int port = HCS_N_PORTS(ehci->hcs_params);
  
  	if (priv->reg_vbus) {
  		if (port > 1) {
  			dev_warn(dev,
  				"Not support multi-port regulator control
  ");
  			return 0;
  		}
  		if (enable)
  			ret = regulator_enable(priv->reg_vbus);
  		else
  			ret = regulator_disable(priv->reg_vbus);
  		if (ret) {
  			dev_err(dev,
  				"Failed to %s vbus regulator, ret=%d
  ",
  				enable ? "enable" : "disable", ret);
  			return ret;
  		}
  	}
  	return 0;
  };
  
  static const struct ehci_driver_overrides ehci_ci_overrides = {
  	.extra_priv_size = sizeof(struct ehci_ci_priv),
  	.port_power	 = ehci_ci_portpower,
  };
  
  static int ci_imx_ehci_bus_resume(struct usb_hcd *hcd)
  {
  	struct ehci_hcd *ehci = hcd_to_ehci(hcd);
  	int port;
  
  	int ret = orig_bus_resume(hcd);
  
  	if (ret)
  		return ret;
  
  	port = HCS_N_PORTS(ehci->hcs_params);
  	while (port--) {
  		u32 __iomem *reg = &ehci->regs->port_status[port];
  		u32 portsc = ehci_readl(ehci, reg);
  		/*
  		 * Notify PHY after resume signal has finished, it is
  		 * for global suspend case.
  		 */
  		if (hcd->usb_phy
  			&& test_bit(port, &ehci->bus_suspended)
  			&& (portsc & PORT_CONNECT)
  			&& (ehci_port_speed(ehci, portsc) ==
  				USB_PORT_STAT_HIGH_SPEED))
  			/* notify the USB PHY */
  			usb_phy_notify_resume(hcd->usb_phy, USB_SPEED_HIGH);
  	}
  
  	return 0;
  }
  
  /* The below code is based on tegra ehci driver */
  static int ci_imx_ehci_hub_control(
  	struct usb_hcd	*hcd,
  	u16		typeReq,
  	u16		wValue,
  	u16		wIndex,
  	char		*buf,
  	u16		wLength
  )
  {
  	struct ehci_hcd	*ehci = hcd_to_ehci(hcd);
  	u32 __iomem	*status_reg;
  	u32		temp;
  	unsigned long	flags;
  	int		retval = 0;
  	struct device *dev = hcd->self.controller;
  	struct ci_hdrc *ci = dev_get_drvdata(dev);
  
  	status_reg = &ehci->regs->port_status[(wIndex & 0xff) - 1];
  
  	spin_lock_irqsave(&ehci->lock, flags);
  
  	if (typeReq == SetPortFeature && wValue == USB_PORT_FEAT_SUSPEND) {
  		temp = ehci_readl(ehci, status_reg);
  		if ((temp & PORT_PE) == 0 || (temp & PORT_RESET) != 0) {
  			retval = -EPIPE;
  			goto done;
  		}
  
  		temp &= ~(PORT_RWC_BITS | PORT_WKCONN_E);
  		temp |= PORT_WKDISC_E | PORT_WKOC_E;
  		ehci_writel(ehci, temp | PORT_SUSPEND, status_reg);
  
  		/*
  		 * If a transaction is in progress, there may be a delay in
  		 * suspending the port. Poll until the port is suspended.
  		 */
  		if (ehci_handshake(ehci, status_reg, PORT_SUSPEND,
  						PORT_SUSPEND, 5000))
  			ehci_err(ehci, "timeout waiting for SUSPEND
  ");
  
  		if (ci->platdata->flags & CI_HDRC_IMX_IS_HSIC) {
  			if (ci->platdata->notify_event)
  				ci->platdata->notify_event
  					(ci, CI_HDRC_IMX_HSIC_SUSPEND_EVENT);
  			ci_ehci_override_wakeup_flag(ehci, status_reg,
  				PORT_WKDISC_E | PORT_WKCONN_E, false);
  		}
  
  		spin_unlock_irqrestore(&ehci->lock, flags);
  		if (ehci_port_speed(ehci, temp) ==
  				USB_PORT_STAT_HIGH_SPEED && hcd->usb_phy) {
  			/* notify the USB PHY */
  			usb_phy_notify_suspend(hcd->usb_phy, USB_SPEED_HIGH);
  		}
  		spin_lock_irqsave(&ehci->lock, flags);
  
  		set_bit((wIndex & 0xff) - 1, &ehci->suspended_ports);
  		goto done;
  	}
  
  	/*
  	 * After resume has finished, it needs do some post resume
  	 * operation for some SoCs.
  	 */
  	else if (typeReq == ClearPortFeature &&
  					wValue == USB_PORT_FEAT_C_SUSPEND) {
  
  		/* Make sure the resume has finished, it should be finished */
  		if (ehci_handshake(ehci, status_reg, PORT_RESUME, 0, 25000))
  			ehci_err(ehci, "timeout waiting for resume
  ");
  
  		temp = ehci_readl(ehci, status_reg);
  
  		if (ehci_port_speed(ehci, temp) ==
  				USB_PORT_STAT_HIGH_SPEED && hcd->usb_phy) {
  			/* notify the USB PHY */
  			usb_phy_notify_resume(hcd->usb_phy, USB_SPEED_HIGH);
  		}
  	}
  
  	spin_unlock_irqrestore(&ehci->lock, flags);
  
  	/* Handle the hub control events here */
  	return orig_hub_control(hcd, typeReq, wValue, wIndex, buf, wLength);
  done:
  	spin_unlock_irqrestore(&ehci->lock, flags);
  	return retval;
  }
  
  static irqreturn_t host_irq(struct ci_hdrc *ci)
  {
  	return usb_hcd_irq(ci->irq, ci->hcd);
  }
  
  static int host_start(struct ci_hdrc *ci)
  {
  	struct usb_hcd *hcd;
  	struct ehci_hcd *ehci;
  	struct ehci_ci_priv *priv;
  	int ret;
  
  	if (usb_disabled())
  		return -ENODEV;
  
  	hcd = usb_create_hcd(&ci_ehci_hc_driver, ci->dev, dev_name(ci->dev));
  	if (!hcd)
  		return -ENOMEM;
  
  	dev_set_drvdata(ci->dev, ci);
  	hcd->rsrc_start = ci->hw_bank.phys;
  	hcd->rsrc_len = ci->hw_bank.size;
  	hcd->regs = ci->hw_bank.abs;
  	hcd->has_tt = 1;
  
  	hcd->power_budget = ci->platdata->power_budget;
  	hcd->tpl_support = ci->platdata->tpl_support;
  	if (ci->phy)
  		hcd->phy = ci->phy;
  	else
  		hcd->usb_phy = ci->usb_phy;
  
  	ehci = hcd_to_ehci(hcd);
  	ehci->caps = ci->hw_bank.cap;
  	ehci->has_hostpc = ci->hw_bank.lpm;
  	ehci->has_tdi_phy_lpm = ci->hw_bank.lpm;
  	ehci->imx28_write_fix = ci->imx28_write_fix;
  
  	priv = (struct ehci_ci_priv *)ehci->priv;
  	priv->reg_vbus = NULL;
  
  	if (ci->platdata->reg_vbus && !ci_otg_is_fsm_mode(ci)) {
  		if (ci->platdata->flags & CI_HDRC_IMX_VBUS_EARLY_ON) {
  			ret = regulator_enable(ci->platdata->reg_vbus);
  			if (ret) {
  				dev_err(ci->dev,
  				"Failed to enable vbus regulator, ret=%d
  ",
  									ret);
  				goto put_hcd;
  			}
  		} else {
  			priv->reg_vbus = ci->platdata->reg_vbus;
  		}
  	}
  
  	ret = usb_add_hcd(hcd, 0, 0);
  	if (ret) {
  		goto disable_reg;
  	} else {
  		struct usb_otg *otg = &ci->otg;
  
  		ci->hcd = hcd;
  
  		if (ci_otg_is_fsm_mode(ci)) {
  			hcd->self.otg_fsm = &ci->fsm;
  			otg->host = &hcd->self;
  			hcd->self.otg_port = 1;
  		}
  	}
  
  	if (ci->platdata->flags & CI_HDRC_DISABLE_STREAMING)
  		hw_write(ci, OP_USBMODE, USBMODE_CI_SDIS, USBMODE_CI_SDIS);
  
  	if (ci->platdata->notify_event &&
  		(ci->platdata->flags & CI_HDRC_IMX_IS_HSIC))
  		ci->platdata->notify_event
  			(ci, CI_HDRC_IMX_HSIC_ACTIVE_EVENT);
  
  	if (ci->platdata->flags & CI_HDRC_DISABLE_HOST_STREAMING)
  		hw_write(ci, OP_USBMODE, USBMODE_CI_SDIS, USBMODE_CI_SDIS);
  
  	ci_hdrc_ahb_config(ci);
  
  	return ret;
  
  disable_reg:
  	if (ci->platdata->reg_vbus && !ci_otg_is_fsm_mode(ci) &&
  			(ci->platdata->flags & CI_HDRC_IMX_VBUS_EARLY_ON))
  		regulator_disable(ci->platdata->reg_vbus);
  put_hcd:
  	usb_put_hcd(hcd);
  
  	return ret;
  }
  
  static void host_stop(struct ci_hdrc *ci)
  {
  	struct usb_hcd *hcd = ci->hcd;
  
  	if (hcd) {
  		usb_remove_hcd(hcd);
  		usb_put_hcd(hcd);
  		if (ci->platdata->reg_vbus && !ci_otg_is_fsm_mode(ci) &&
  			(ci->platdata->flags & CI_HDRC_IMX_VBUS_EARLY_ON))
  				regulator_disable(ci->platdata->reg_vbus);
  	}
  	ci->hcd = NULL;
  }
  
  bool ci_hdrc_host_has_device(struct ci_hdrc *ci)
  {
  	struct usb_device *roothub;
  	int i;
  
  	if ((ci->role == CI_ROLE_HOST) && ci->hcd) {
  		roothub = ci->hcd->self.root_hub;
  		for (i = 0; i < roothub->maxchild; ++i) {
  			if (usb_hub_find_child(roothub, (i + 1)))
  				return true;
  		}
  	}
  	return false;
  }
  
  static void ci_hdrc_host_save_for_power_lost(struct ci_hdrc *ci)
  {
  	struct ehci_hcd *ehci;
  
  	if (!ci->hcd)
  		return;
  
  	ehci = hcd_to_ehci(ci->hcd);
  	/* save EHCI registers */
  	ci->pm_usbmode = ehci_readl(ehci, &ehci->regs->usbmode);
  	ci->pm_command = ehci_readl(ehci, &ehci->regs->command);
  	ci->pm_command &= ~CMD_RUN;
  	ci->pm_status  = ehci_readl(ehci, &ehci->regs->status);
  	ci->pm_intr_enable  = ehci_readl(ehci, &ehci->regs->intr_enable);
  	ci->pm_frame_index  = ehci_readl(ehci, &ehci->regs->frame_index);
  	ci->pm_segment  = ehci_readl(ehci, &ehci->regs->segment);
  	ci->pm_frame_list  = ehci_readl(ehci, &ehci->regs->frame_list);
  	ci->pm_async_next  = ehci_readl(ehci, &ehci->regs->async_next);
  	ci->pm_configured_flag  =
  			ehci_readl(ehci, &ehci->regs->configured_flag);
  	ci->pm_portsc = ehci_readl(ehci, &ehci->regs->port_status[0]);
  }
  
  static void ci_hdrc_host_restore_from_power_lost(struct ci_hdrc *ci)
  {
  	struct ehci_hcd *ehci;
  	unsigned long   flags;
  	u32 tmp;
  
  	if (!ci->hcd)
  		return;
  
  	hw_controller_reset(ci);
  
  	ehci = hcd_to_ehci(ci->hcd);
  	spin_lock_irqsave(&ehci->lock, flags);
  	/* Restore EHCI registers */
  	ehci_writel(ehci, ci->pm_usbmode, &ehci->regs->usbmode);
  	ehci_writel(ehci, ci->pm_portsc, &ehci->regs->port_status[0]);
  	ehci_writel(ehci, ci->pm_command, &ehci->regs->command);
  	ehci_writel(ehci, ci->pm_intr_enable, &ehci->regs->intr_enable);
  	ehci_writel(ehci, ci->pm_frame_index, &ehci->regs->frame_index);
  	ehci_writel(ehci, ci->pm_segment, &ehci->regs->segment);
  	ehci_writel(ehci, ci->pm_frame_list, &ehci->regs->frame_list);
  	ehci_writel(ehci, ci->pm_async_next, &ehci->regs->async_next);
  	ehci_writel(ehci, ci->pm_configured_flag,
  					&ehci->regs->configured_flag);
  	/* Restore the PHY's connect notifier setting */
  	if (ci->pm_portsc & PORTSC_HSP)
  		usb_phy_notify_connect(ci->usb_phy, USB_SPEED_HIGH);
  
  	ci_hdrc_ahb_config(ci);
  
  	tmp = ehci_readl(ehci, &ehci->regs->command);
  	tmp |= CMD_RUN;
  	ehci_writel(ehci, tmp, &ehci->regs->command);
  	spin_unlock_irqrestore(&ehci->lock, flags);
  }
  
  static void ci_hdrc_host_suspend(struct ci_hdrc *ci)
  {
  	if (ci_hdrc_host_has_device(ci))
  		imx_gpc_mf_request_on(ci->irq, 1);
  
  	ci_hdrc_host_save_for_power_lost(ci);
  }
  
  static void ci_hdrc_host_resume(struct ci_hdrc *ci, bool power_lost)
  {
  	imx_gpc_mf_request_on(ci->irq, 0);
  
  	if (power_lost)
  		ci_hdrc_host_restore_from_power_lost(ci);
  }
  
  void ci_hdrc_host_destroy(struct ci_hdrc *ci)
  {
  	if (ci->role == CI_ROLE_HOST && ci->hcd)
  		host_stop(ci);
  }
  
  static int ci_ehci_bus_suspend(struct usb_hcd *hcd)
  {
  	struct ehci_hcd *ehci = hcd_to_ehci(hcd);
  	int port;
  	u32 tmp;
  	struct device *dev = hcd->self.controller;
  	struct ci_hdrc *ci = dev_get_drvdata(dev);
  
  	int ret = orig_bus_suspend(hcd);
  
  	if (ret)
  		return ret;
  
  	port = HCS_N_PORTS(ehci->hcs_params);
  	while (port--) {
  		u32 __iomem *reg = &ehci->regs->port_status[port];
  		u32 portsc = ehci_readl(ehci, reg);
  
  		if (portsc & PORT_CONNECT) {
  			/*
  			 * For chipidea, the resume signal will be ended
  			 * automatically, so for remote wakeup case, the
  			 * usbcmd.rs may not be set before the resume has
  			 * ended if other resume paths consumes too much
  			 * time (~24ms), in that case, the SOF will not
  			 * send out within 3ms after resume ends, then the
  			 * high speed device will enter full speed mode.
  			 */
  
  			tmp = ehci_readl(ehci, &ehci->regs->command);
  			tmp |= CMD_RUN;
  			ehci_writel(ehci, tmp, &ehci->regs->command);
  			/*
  			 * It needs a short delay between set RS bit and PHCD.
  			 */
  			usleep_range(150, 200);
  
  			/*
  			 * If a transaction is in progress, there may be a delay in
  			 * suspending the port. Poll until the port is suspended.
  			 */
  			if (ehci_handshake(ehci, reg, PORT_SUSPEND,
  							PORT_SUSPEND, 5000))
  				ehci_err(ehci, "timeout waiting for SUSPEND
  ");
  
  			if (ci->platdata->flags & CI_HDRC_IMX_IS_HSIC)
  				ci_ehci_override_wakeup_flag(ehci, reg,
  					PORT_WKDISC_E | PORT_WKCONN_E, false);
  
  			if (hcd->usb_phy && test_bit(port, &ehci->bus_suspended)
  				&& (ehci_port_speed(ehci, portsc) ==
  					USB_PORT_STAT_HIGH_SPEED))
  				/*
  				 * notify the USB PHY, it is for global
  				 * suspend case.
  				 */
  				usb_phy_notify_suspend(hcd->usb_phy,
  					USB_SPEED_HIGH);
  			break;
  		}
  	}
  
  	return 0;
  }
  
  int ci_hdrc_host_init(struct ci_hdrc *ci)
  {
  	struct ci_role_driver *rdrv;
  
  	if (!hw_read(ci, CAP_DCCPARAMS, DCCPARAMS_HC))
  		return -ENXIO;
  
  	rdrv = devm_kzalloc(ci->dev, sizeof(struct ci_role_driver), GFP_KERNEL);
  	if (!rdrv)
  		return -ENOMEM;
  
  	rdrv->start	= host_start;
  	rdrv->stop	= host_stop;
  	rdrv->irq	= host_irq;
  	rdrv->suspend	= ci_hdrc_host_suspend;
  	rdrv->resume	= ci_hdrc_host_resume;
  	rdrv->name	= "host";
  	ci->roles[CI_ROLE_HOST] = rdrv;
  
  	ehci_init_driver(&ci_ehci_hc_driver, &ehci_ci_overrides);
  	orig_bus_suspend = ci_ehci_hc_driver.bus_suspend;
  	orig_bus_resume = ci_ehci_hc_driver.bus_resume;
  	orig_hub_control = ci_ehci_hc_driver.hub_control;
  
  	ci_ehci_hc_driver.bus_suspend = ci_ehci_bus_suspend;
  	if (ci->platdata->flags & CI_HDRC_IMX_EHCI_QUIRK) {
  		ci_ehci_hc_driver.bus_resume = ci_imx_ehci_bus_resume;
  		ci_ehci_hc_driver.hub_control = ci_imx_ehci_hub_control;
  	}
  
  	return 0;
  }