Quelle  dwc3-imx8mp.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0
/*
 * dwc3-imx8mp.c - NXP imx8mp Specific Glue layer
 *
 * Copyright (c) 2020 NXP.
 */

#include <linux/cleanup.h>
#include <linux/clk.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>

#include "core.h"

/* USB wakeup registers */
#define USB_WAKEUP_CTRL   0x00

/* Global wakeup interrupt enable, also used to clear interrupt */
#define USB_WAKEUP_EN   BIT(31)
/* Wakeup from connect or disconnect, only for superspeed */
#define USB_WAKEUP_SS_CONN  BIT(5)
/* 0 select vbus_valid, 1 select sessvld */
#define USB_WAKEUP_VBUS_SRC_SESS_VAL BIT(4)
/* Enable signal for wake up from u3 state */
#define USB_WAKEUP_U3_EN  BIT(3)
/* Enable signal for wake up from id change */
#define USB_WAKEUP_ID_EN  BIT(2)
/* Enable signal for wake up from vbus change */
#define USB_WAKEUP_VBUS_EN  BIT(1)
/* Enable signal for wake up from dp/dm change */
#define USB_WAKEUP_DPDM_EN  BIT(0)

#define USB_WAKEUP_EN_MASK  GENMASK(5, 0)

/* USB glue registers */
#define USB_CTRL0  0x00
#define USB_CTRL1  0x04

#define USB_CTRL0_PORTPWR_EN BIT(12) /* 1 - PPC enabled (default) */
#define USB_CTRL0_USB3_FIXED BIT(22) /* 1 - USB3 permanent attached */
#define USB_CTRL0_USB2_FIXED BIT(23) /* 1 - USB2 permanent attached */

#define USB_CTRL1_OC_POLARITY BIT(16) /* 0 - HIGH / 1 - LOW */
#define USB_CTRL1_PWR_POLARITY BIT(17) /* 0 - HIGH / 1 - LOW */

struct dwc3_imx8mp {
 struct device   *dev;
 struct platform_device  *dwc3;
 void __iomem   *hsio_blk_base;
 void __iomem   *glue_base;
 struct clk   *hsio_clk;
 struct clk   *suspend_clk;
 int    irq;
 bool    pm_suspended;
 bool    wakeup_pending;
};

static void imx8mp_configure_glue(struct dwc3_imx8mp *dwc3_imx)
{
 struct device *dev = dwc3_imx->dev;
 u32 value;

 if (!dwc3_imx->glue_base)
  return;

 value = readl(dwc3_imx->glue_base + USB_CTRL0);

 if (device_property_read_bool(dev, "fsl,permanently-attached"))
  value |= (USB_CTRL0_USB2_FIXED | USB_CTRL0_USB3_FIXED);
 else
  value &= ~(USB_CTRL0_USB2_FIXED | USB_CTRL0_USB3_FIXED);

 if (device_property_read_bool(dev, "fsl,disable-port-power-control"))
  value &= ~(USB_CTRL0_PORTPWR_EN);
 else
  value |= USB_CTRL0_PORTPWR_EN;

 writel(value, dwc3_imx->glue_base + USB_CTRL0);

 value = readl(dwc3_imx->glue_base + USB_CTRL1);
 if (device_property_read_bool(dev, "fsl,over-current-active-low"))
  value |= USB_CTRL1_OC_POLARITY;
 else
  value &= ~USB_CTRL1_OC_POLARITY;

 if (device_property_read_bool(dev, "fsl,power-active-low"))
  value |= USB_CTRL1_PWR_POLARITY;
 else
  value &= ~USB_CTRL1_PWR_POLARITY;

 writel(value, dwc3_imx->glue_base + USB_CTRL1);
}

static void dwc3_imx8mp_wakeup_enable(struct dwc3_imx8mp *dwc3_imx,
          pm_message_t msg)
{
 struct dwc3 *dwc3 = platform_get_drvdata(dwc3_imx->dwc3);
 u32  val;

 if (!dwc3)
  return;

 val = readl(dwc3_imx->hsio_blk_base + USB_WAKEUP_CTRL);

 if ((dwc3->current_dr_role == DWC3_GCTL_PRTCAP_HOST) && dwc3->xhci) {
  val |= USB_WAKEUP_EN | USB_WAKEUP_DPDM_EN;
  if (PMSG_IS_AUTO(msg))
   val |= USB_WAKEUP_SS_CONN | USB_WAKEUP_U3_EN;
 } else {
  val |= USB_WAKEUP_EN | USB_WAKEUP_VBUS_EN |
         USB_WAKEUP_VBUS_SRC_SESS_VAL;
 }

 writel(val, dwc3_imx->hsio_blk_base + USB_WAKEUP_CTRL);
}

static void dwc3_imx8mp_wakeup_disable(struct dwc3_imx8mp *dwc3_imx)
{
 u32 val;

 val = readl(dwc3_imx->hsio_blk_base + USB_WAKEUP_CTRL);
 val &= ~(USB_WAKEUP_EN | USB_WAKEUP_EN_MASK);
 writel(val, dwc3_imx->hsio_blk_base + USB_WAKEUP_CTRL);
}

static const struct property_entry dwc3_imx8mp_properties[] = {
 PROPERTY_ENTRY_BOOL("xhci-missing-cas-quirk"),
 PROPERTY_ENTRY_BOOL("xhci-skip-phy-init-quirk"),
 {},
};

static const struct software_node dwc3_imx8mp_swnode = {
 .properties = dwc3_imx8mp_properties,
};

static irqreturn_t dwc3_imx8mp_interrupt(int irq, void *_dwc3_imx)
{
 struct dwc3_imx8mp *dwc3_imx = _dwc3_imx;
 struct dwc3  *dwc = platform_get_drvdata(dwc3_imx->dwc3);

 if (!dwc3_imx->pm_suspended)
  return IRQ_HANDLED;

 disable_irq_nosync(dwc3_imx->irq);
 dwc3_imx->wakeup_pending = true;

 if ((dwc->current_dr_role == DWC3_GCTL_PRTCAP_HOST) && dwc->xhci)
  pm_runtime_resume(&dwc->xhci->dev);
 else if (dwc->current_dr_role == DWC3_GCTL_PRTCAP_DEVICE)
  pm_runtime_get(dwc->dev);

 return IRQ_HANDLED;
}

static int dwc3_imx8mp_probe(struct platform_device *pdev)
{
 struct device  *dev = &pdev->dev;
 struct device_node *node = dev->of_node;
 struct dwc3_imx8mp *dwc3_imx;
 struct resource  *res;
 int   err, irq;

 if (!node) {
  dev_err(dev, "device node not found\n");
  return -EINVAL;
 }

 dwc3_imx = devm_kzalloc(dev, sizeof(*dwc3_imx), GFP_KERNEL);
 if (!dwc3_imx)
  return -ENOMEM;

 platform_set_drvdata(pdev, dwc3_imx);

 dwc3_imx->dev = dev;

 dwc3_imx->hsio_blk_base = devm_platform_ioremap_resource(pdev, 0);
 if (IS_ERR(dwc3_imx->hsio_blk_base))
  return PTR_ERR(dwc3_imx->hsio_blk_base);

 res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 if (!res) {
  dev_warn(dev, "Base address for glue layer missing. Continuing without, some features are missing though.");
 } else {
  dwc3_imx->glue_base = devm_ioremap_resource(dev, res);
  if (IS_ERR(dwc3_imx->glue_base))
   return PTR_ERR(dwc3_imx->glue_base);
 }

 dwc3_imx->hsio_clk = devm_clk_get_enabled(dev, "hsio");
 if (IS_ERR(dwc3_imx->hsio_clk))
  return dev_err_probe(dev, PTR_ERR(dwc3_imx->hsio_clk),
         "Failed to get hsio clk\n");

 dwc3_imx->suspend_clk = devm_clk_get_enabled(dev, "suspend");
 if (IS_ERR(dwc3_imx->suspend_clk))
  return dev_err_probe(dev, PTR_ERR(dwc3_imx->suspend_clk),
         "Failed to get suspend clk\n");

 irq = platform_get_irq(pdev, 0);
 if (irq < 0)
  return irq;
 dwc3_imx->irq = irq;

 struct device_node *dwc3_np __free(device_node) = of_get_compatible_child(node,
            "snps,dwc3");
 if (!dwc3_np)
  return dev_err_probe(dev, -ENODEV, "failed to find dwc3 core child\n");

 imx8mp_configure_glue(dwc3_imx);

 pm_runtime_set_active(dev);
 pm_runtime_enable(dev);
 err = pm_runtime_get_sync(dev);
 if (err < 0)
  goto disable_rpm;

 err = device_add_software_node(dev, &dwc3_imx8mp_swnode);
 if (err) {
  err = -ENODEV;
  dev_err(dev, "failed to add software node\n");
  goto disable_rpm;
 }

 err = of_platform_populate(node, NULL, NULL, dev);
 if (err) {
  dev_err(&pdev->dev, "failed to create dwc3 core\n");
  goto remove_swnode;
 }

 dwc3_imx->dwc3 = of_find_device_by_node(dwc3_np);
 if (!dwc3_imx->dwc3) {
  dev_err(dev, "failed to get dwc3 platform device\n");
  err = -ENODEV;
  goto depopulate;
 }

 err = devm_request_threaded_irq(dev, irq, NULL, dwc3_imx8mp_interrupt,
     IRQF_ONESHOT, dev_name(dev), dwc3_imx);
 if (err) {
  dev_err(dev, "failed to request IRQ #%d --> %d\n", irq, err);
  goto put_dwc3;
 }

 device_set_wakeup_capable(dev, true);
 pm_runtime_put(dev);

 return 0;

put_dwc3:
 put_device(&dwc3_imx->dwc3->dev);
depopulate:
 of_platform_depopulate(dev);
remove_swnode:
 device_remove_software_node(dev);
disable_rpm:
 pm_runtime_disable(dev);
 pm_runtime_put_noidle(dev);

 return err;
}

static void dwc3_imx8mp_remove(struct platform_device *pdev)
{
 struct dwc3_imx8mp *dwc3_imx = platform_get_drvdata(pdev);
 struct device *dev = &pdev->dev;

 put_device(&dwc3_imx->dwc3->dev);

 pm_runtime_get_sync(dev);
 of_platform_depopulate(dev);
 device_remove_software_node(dev);

 pm_runtime_disable(dev);
 pm_runtime_put_noidle(dev);
}

static int dwc3_imx8mp_suspend(struct dwc3_imx8mp *dwc3_imx, pm_message_t msg)
{
 if (dwc3_imx->pm_suspended)
  return 0;

 /* Wakeup enable */
 if (PMSG_IS_AUTO(msg) || device_may_wakeup(dwc3_imx->dev))
  dwc3_imx8mp_wakeup_enable(dwc3_imx, msg);

 dwc3_imx->pm_suspended = true;

 return 0;
}

static int dwc3_imx8mp_resume(struct dwc3_imx8mp *dwc3_imx, pm_message_t msg)
{
 struct dwc3 *dwc = platform_get_drvdata(dwc3_imx->dwc3);
 int ret = 0;

 if (!dwc3_imx->pm_suspended)
  return 0;

 /* Wakeup disable */
 dwc3_imx8mp_wakeup_disable(dwc3_imx);
 dwc3_imx->pm_suspended = false;

 /* Upon power loss any previous configuration is lost, restore it */
 imx8mp_configure_glue(dwc3_imx);

 if (dwc3_imx->wakeup_pending) {
  dwc3_imx->wakeup_pending = false;
  if (dwc->current_dr_role == DWC3_GCTL_PRTCAP_DEVICE) {
   pm_runtime_mark_last_busy(dwc->dev);
   pm_runtime_put_autosuspend(dwc->dev);
  } else {
   /*
 * Add wait for xhci switch from suspend
 * clock to normal clock to detect connection.
 */
   usleep_range(9000, 10000);
  }
  enable_irq(dwc3_imx->irq);
 }

 return ret;
}

static int dwc3_imx8mp_pm_suspend(struct device *dev)
{
 struct dwc3_imx8mp *dwc3_imx = dev_get_drvdata(dev);
 int ret;

 ret = dwc3_imx8mp_suspend(dwc3_imx, PMSG_SUSPEND);

 if (device_may_wakeup(dwc3_imx->dev))
  enable_irq_wake(dwc3_imx->irq);
 else
  clk_disable_unprepare(dwc3_imx->suspend_clk);

 clk_disable_unprepare(dwc3_imx->hsio_clk);
 dev_dbg(dev, "dwc3 imx8mp pm suspend.\n");

 return ret;
}

static int dwc3_imx8mp_pm_resume(struct device *dev)
{
 struct dwc3_imx8mp *dwc3_imx = dev_get_drvdata(dev);
 int ret;

 if (device_may_wakeup(dwc3_imx->dev)) {
  disable_irq_wake(dwc3_imx->irq);
 } else {
  ret = clk_prepare_enable(dwc3_imx->suspend_clk);
  if (ret)
   return ret;
 }

 ret = clk_prepare_enable(dwc3_imx->hsio_clk);
 if (ret) {
  clk_disable_unprepare(dwc3_imx->suspend_clk);
  return ret;
 }

 ret = dwc3_imx8mp_resume(dwc3_imx, PMSG_RESUME);

 pm_runtime_disable(dev);
 pm_runtime_set_active(dev);
 pm_runtime_enable(dev);

 dev_dbg(dev, "dwc3 imx8mp pm resume.\n");

 return ret;
}

static int dwc3_imx8mp_runtime_suspend(struct device *dev)
{
 struct dwc3_imx8mp *dwc3_imx = dev_get_drvdata(dev);

 dev_dbg(dev, "dwc3 imx8mp runtime suspend.\n");

 return dwc3_imx8mp_suspend(dwc3_imx, PMSG_AUTO_SUSPEND);
}

static int dwc3_imx8mp_runtime_resume(struct device *dev)
{
 struct dwc3_imx8mp *dwc3_imx = dev_get_drvdata(dev);

 dev_dbg(dev, "dwc3 imx8mp runtime resume.\n");

 return dwc3_imx8mp_resume(dwc3_imx, PMSG_AUTO_RESUME);
}

static const struct dev_pm_ops dwc3_imx8mp_dev_pm_ops = {
 SYSTEM_SLEEP_PM_OPS(dwc3_imx8mp_pm_suspend, dwc3_imx8mp_pm_resume)
 RUNTIME_PM_OPS(dwc3_imx8mp_runtime_suspend, dwc3_imx8mp_runtime_resume,
         NULL)
};

static const struct of_device_id dwc3_imx8mp_of_match[] = {
 { .compatible = "fsl,imx8mp-dwc3", },
 {},
};
MODULE_DEVICE_TABLE(of, dwc3_imx8mp_of_match);

static struct platform_driver dwc3_imx8mp_driver = {
 .probe  = dwc3_imx8mp_probe,
 .remove  = dwc3_imx8mp_remove,
 .driver  = {
  .name = "imx8mp-dwc3",
  .pm = pm_ptr(&dwc3_imx8mp_dev_pm_ops),
  .of_match_table = dwc3_imx8mp_of_match,
 },
};

module_platform_driver(dwc3_imx8mp_driver);

MODULE_ALIAS("platform:imx8mp-dwc3");
MODULE_AUTHOR("jun.li@nxp.com");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("DesignWare USB3 imx8mp Glue Layer");