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|
// SPDX-License-Identifier: GPL-2.0
/*
* Cadence USBSS DRD Driver.
*
* Copyright (C) 2018-2019 Cadence.
* Copyright (C) 2017-2018 NXP
* Copyright (C) 2019 Texas Instruments
*
* Author: Peter Chen <peter.chen@nxp.com>
* Pawel Laszczak <pawell@cadence.com>
* Roger Quadros <rogerq@ti.com>
*/
#include <linux/dma-mapping.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/pm_runtime.h>
#include "gadget.h"
#include "core.h"
#include "host-export.h"
#include "gadget-export.h"
#include "drd.h"
static int cdns3_idle_init(struct cdns3 *cdns);
static inline
struct cdns3_role_driver *cdns3_get_current_role_driver(struct cdns3 *cdns)
{
WARN_ON(!cdns->roles[cdns->role]);
return cdns->roles[cdns->role];
}
static int cdns3_role_start(struct cdns3 *cdns, enum usb_role role)
{
int ret;
if (WARN_ON(role > USB_ROLE_DEVICE))
return 0;
mutex_lock(&cdns->mutex);
cdns->role = role;
mutex_unlock(&cdns->mutex);
if (!cdns->roles[role])
return -ENXIO;
if (cdns->roles[role]->state == CDNS3_ROLE_STATE_ACTIVE)
return 0;
mutex_lock(&cdns->mutex);
ret = cdns->roles[role]->start(cdns);
if (!ret)
cdns->roles[role]->state = CDNS3_ROLE_STATE_ACTIVE;
mutex_unlock(&cdns->mutex);
return ret;
}
static void cdns3_role_stop(struct cdns3 *cdns)
{
enum usb_role role = cdns->role;
if (WARN_ON(role > USB_ROLE_DEVICE))
return;
if (cdns->roles[role]->state == CDNS3_ROLE_STATE_INACTIVE)
return;
mutex_lock(&cdns->mutex);
cdns->roles[role]->stop(cdns);
cdns->roles[role]->state = CDNS3_ROLE_STATE_INACTIVE;
mutex_unlock(&cdns->mutex);
}
static void cdns3_exit_roles(struct cdns3 *cdns)
{
cdns3_role_stop(cdns);
cdns3_drd_exit(cdns);
}
static enum usb_role cdsn3_hw_role_state_machine(struct cdns3 *cdns);
/**
* cdns3_core_init_role - initialize role of operation
* @cdns: Pointer to cdns3 structure
*
* Returns 0 on success otherwise negative errno
*/
static int cdns3_core_init_role(struct cdns3 *cdns)
{
struct device *dev = cdns->dev;
enum usb_dr_mode best_dr_mode;
enum usb_dr_mode dr_mode;
int ret = 0;
dr_mode = usb_get_dr_mode(dev);
cdns->role = USB_ROLE_NONE;
/*
* If driver can't read mode by means of usb_get_dr_mode function then
* chooses mode according with Kernel configuration. This setting
* can be restricted later depending on strap pin configuration.
*/
if (dr_mode == USB_DR_MODE_UNKNOWN) {
if (IS_ENABLED(CONFIG_USB_CDNS3_HOST) &&
IS_ENABLED(CONFIG_USB_CDNS3_GADGET))
dr_mode = USB_DR_MODE_OTG;
else if (IS_ENABLED(CONFIG_USB_CDNS3_HOST))
dr_mode = USB_DR_MODE_HOST;
else if (IS_ENABLED(CONFIG_USB_CDNS3_GADGET))
dr_mode = USB_DR_MODE_PERIPHERAL;
}
/*
* At this point cdns->dr_mode contains strap configuration.
* Driver try update this setting considering kernel configuration
*/
best_dr_mode = cdns->dr_mode;
ret = cdns3_idle_init(cdns);
if (ret)
return ret;
if (dr_mode == USB_DR_MODE_OTG) {
best_dr_mode = cdns->dr_mode;
} else if (cdns->dr_mode == USB_DR_MODE_OTG) {
best_dr_mode = dr_mode;
} else if (cdns->dr_mode != dr_mode) {
dev_err(dev, "Incorrect DRD configuration\n");
return -EINVAL;
}
dr_mode = best_dr_mode;
if (dr_mode == USB_DR_MODE_OTG || dr_mode == USB_DR_MODE_HOST) {
ret = cdns3_host_init(cdns);
if (ret) {
dev_err(dev, "Host initialization failed with %d\n",
ret);
goto err;
}
}
if (dr_mode == USB_DR_MODE_OTG || dr_mode == USB_DR_MODE_PERIPHERAL) {
ret = cdns3_gadget_init(cdns);
if (ret) {
dev_err(dev, "Device initialization failed with %d\n",
ret);
goto err;
}
}
cdns->dr_mode = dr_mode;
ret = cdns3_drd_update_mode(cdns);
if (ret)
goto err;
if (cdns->dr_mode != USB_DR_MODE_OTG) {
ret = cdns3_hw_role_switch(cdns);
if (ret)
goto err;
}
return ret;
err:
cdns3_exit_roles(cdns);
return ret;
}
/**
* cdsn3_hw_role_state_machine - role switch state machine based on hw events.
* @cdns: Pointer to controller structure.
*
* Returns next role to be entered based on hw events.
*/
static enum usb_role cdsn3_hw_role_state_machine(struct cdns3 *cdns)
{
enum usb_role role;
int id, vbus;
if (cdns->dr_mode != USB_DR_MODE_OTG)
goto not_otg;
id = cdns3_get_id(cdns);
vbus = cdns3_get_vbus(cdns);
/*
* Role change state machine
* Inputs: ID, VBUS
* Previous state: cdns->role
* Next state: role
*/
role = cdns->role;
switch (role) {
case USB_ROLE_NONE:
/*
* Driver treats USB_ROLE_NONE synonymous to IDLE state from
* controller specification.
*/
if (!id)
role = USB_ROLE_HOST;
else if (vbus)
role = USB_ROLE_DEVICE;
break;
case USB_ROLE_HOST: /* from HOST, we can only change to NONE */
if (id)
role = USB_ROLE_NONE;
break;
case USB_ROLE_DEVICE: /* from GADGET, we can only change to NONE*/
if (!vbus)
role = USB_ROLE_NONE;
break;
}
dev_dbg(cdns->dev, "role %d -> %d\n", cdns->role, role);
return role;
not_otg:
if (cdns3_is_host(cdns))
role = USB_ROLE_HOST;
if (cdns3_is_device(cdns))
role = USB_ROLE_DEVICE;
return role;
}
static int cdns3_idle_role_start(struct cdns3 *cdns)
{
return 0;
}
static void cdns3_idle_role_stop(struct cdns3 *cdns)
{
/* Program Lane swap and bring PHY out of RESET */
phy_reset(cdns->usb3_phy);
}
static int cdns3_idle_init(struct cdns3 *cdns)
{
struct cdns3_role_driver *rdrv;
rdrv = devm_kzalloc(cdns->dev, sizeof(*rdrv), GFP_KERNEL);
if (!rdrv)
return -ENOMEM;
rdrv->start = cdns3_idle_role_start;
rdrv->stop = cdns3_idle_role_stop;
rdrv->state = CDNS3_ROLE_STATE_INACTIVE;
rdrv->suspend = NULL;
rdrv->resume = NULL;
rdrv->name = "idle";
cdns->roles[USB_ROLE_NONE] = rdrv;
return 0;
}
/**
* cdns3_hw_role_switch - switch roles based on HW state
* @cdns3: controller
*/
int cdns3_hw_role_switch(struct cdns3 *cdns)
{
enum usb_role real_role, current_role;
int ret = 0;
/* Do nothing if role based on syfs. */
if (cdns->role_override)
return 0;
pm_runtime_get_sync(cdns->dev);
current_role = cdns->role;
real_role = cdsn3_hw_role_state_machine(cdns);
/* Do nothing if nothing changed */
if (current_role == real_role)
goto exit;
cdns3_role_stop(cdns);
dev_dbg(cdns->dev, "Switching role %d -> %d", current_role, real_role);
ret = cdns3_role_start(cdns, real_role);
if (ret) {
/* Back to current role */
dev_err(cdns->dev, "set %d has failed, back to %d\n",
real_role, current_role);
ret = cdns3_role_start(cdns, current_role);
if (ret)
dev_err(cdns->dev, "back to %d failed too\n",
current_role);
}
exit:
pm_runtime_put_sync(cdns->dev);
return ret;
}
/**
* cdsn3_role_get - get current role of controller.
*
* @dev: Pointer to device structure
*
* Returns role
*/
static enum usb_role cdns3_role_get(struct device *dev)
{
struct cdns3 *cdns = dev_get_drvdata(dev);
return cdns->role;
}
/**
* cdns3_role_set - set current role of controller.
*
* @dev: pointer to device object
* @role - the previous role
* Handles below events:
* - Role switch for dual-role devices
* - USB_ROLE_GADGET <--> USB_ROLE_NONE for peripheral-only devices
*/
static int cdns3_role_set(struct device *dev, enum usb_role role)
{
struct cdns3 *cdns = dev_get_drvdata(dev);
int ret = 0;
pm_runtime_get_sync(cdns->dev);
/*
* FIXME: switch role framework should be extended to meet
* requirements. Driver assumes that role can be controlled
* by SW or HW. Temporary workaround is to use USB_ROLE_NONE to
* switch from SW to HW control.
*
* For dr_mode == USB_DR_MODE_OTG:
* if user sets USB_ROLE_HOST or USB_ROLE_DEVICE then driver
* sets role_override flag and forces that role.
* if user sets USB_ROLE_NONE, driver clears role_override and lets
* HW state machine take over.
*
* For dr_mode != USB_DR_MODE_OTG:
* Assumptions:
* 1. Restricted user control between NONE and dr_mode.
* 2. Driver doesn't need to rely on role_override flag.
* 3. Driver needs to ensure that HW state machine is never called
* if dr_mode != USB_DR_MODE_OTG.
*/
if (role == USB_ROLE_NONE)
cdns->role_override = 0;
else
cdns->role_override = 1;
/*
* HW state might have changed so driver need to trigger
* HW state machine if dr_mode == USB_DR_MODE_OTG.
*/
if (!cdns->role_override && cdns->dr_mode == USB_DR_MODE_OTG) {
cdns3_hw_role_switch(cdns);
goto pm_put;
}
if (cdns->role == role)
goto pm_put;
if (cdns->dr_mode == USB_DR_MODE_HOST) {
switch (role) {
case USB_ROLE_NONE:
case USB_ROLE_HOST:
break;
default:
ret = -EPERM;
goto pm_put;
}
}
if (cdns->dr_mode == USB_DR_MODE_PERIPHERAL) {
switch (role) {
case USB_ROLE_NONE:
case USB_ROLE_DEVICE:
break;
default:
ret = -EPERM;
goto pm_put;
}
}
cdns3_role_stop(cdns);
ret = cdns3_role_start(cdns, role);
if (ret) {
dev_err(cdns->dev, "set role %d has failed\n", role);
ret = -EPERM;
}
pm_put:
pm_runtime_put_sync(cdns->dev);
return ret;
}
static const struct usb_role_switch_desc cdns3_switch_desc = {
.set = cdns3_role_set,
.get = cdns3_role_get,
.allow_userspace_control = true,
};
/**
* cdns3_probe - probe for cdns3 core device
* @pdev: Pointer to cdns3 core platform device
*
* Returns 0 on success otherwise negative errno
*/
static int cdns3_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct resource *res;
struct cdns3 *cdns;
void __iomem *regs;
int ret;
ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
if (ret) {
dev_err(dev, "error setting dma mask: %d\n", ret);
return -ENODEV;
}
cdns = devm_kzalloc(dev, sizeof(*cdns), GFP_KERNEL);
if (!cdns)
return -ENOMEM;
cdns->dev = dev;
platform_set_drvdata(pdev, cdns);
res = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "host");
if (!res) {
dev_err(dev, "missing host IRQ\n");
return -ENODEV;
}
cdns->xhci_res[0] = *res;
res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "xhci");
if (!res) {
dev_err(dev, "couldn't get xhci resource\n");
return -ENXIO;
}
cdns->xhci_res[1] = *res;
cdns->dev_irq = platform_get_irq_byname(pdev, "peripheral");
if (cdns->dev_irq == -EPROBE_DEFER)
return cdns->dev_irq;
if (cdns->dev_irq < 0)
dev_err(dev, "couldn't get peripheral irq\n");
res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dev");
regs = devm_ioremap_resource(dev, res);
if (IS_ERR(regs))
return PTR_ERR(regs);
cdns->dev_regs = regs;
cdns->otg_irq = platform_get_irq_byname(pdev, "otg");
if (cdns->otg_irq == -EPROBE_DEFER)
return cdns->otg_irq;
if (cdns->otg_irq < 0) {
dev_err(dev, "couldn't get otg irq\n");
return cdns->otg_irq;
}
res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "otg");
if (!res) {
dev_err(dev, "couldn't get otg resource\n");
return -ENXIO;
}
cdns->otg_res = *res;
mutex_init(&cdns->mutex);
cdns->usb2_phy = devm_phy_optional_get(dev, "cdns3,usb2-phy");
if (IS_ERR(cdns->usb2_phy))
return PTR_ERR(cdns->usb2_phy);
ret = phy_init(cdns->usb2_phy);
if (ret)
return ret;
cdns->usb3_phy = devm_phy_optional_get(dev, "cdns3,usb3-phy");
if (IS_ERR(cdns->usb3_phy))
return PTR_ERR(cdns->usb3_phy);
ret = phy_init(cdns->usb3_phy);
if (ret)
goto err1;
ret = phy_power_on(cdns->usb2_phy);
if (ret)
goto err2;
ret = phy_power_on(cdns->usb3_phy);
if (ret)
goto err3;
cdns->role_sw = usb_role_switch_register(dev, &cdns3_switch_desc);
if (IS_ERR(cdns->role_sw)) {
ret = PTR_ERR(cdns->role_sw);
dev_warn(dev, "Unable to register Role Switch\n");
goto err4;
}
ret = cdns3_drd_init(cdns);
if (ret)
goto err5;
ret = cdns3_core_init_role(cdns);
if (ret)
goto err5;
device_set_wakeup_capable(dev, true);
pm_runtime_set_active(dev);
pm_runtime_enable(dev);
/*
* The controller needs less time between bus and controller suspend,
* and we also needs a small delay to avoid frequently entering low
* power mode.
*/
pm_runtime_set_autosuspend_delay(dev, 20);
pm_runtime_mark_last_busy(dev);
pm_runtime_use_autosuspend(dev);
dev_dbg(dev, "Cadence USB3 core: probe succeed\n");
return 0;
err5:
cdns3_drd_exit(cdns);
usb_role_switch_unregister(cdns->role_sw);
err4:
phy_power_off(cdns->usb3_phy);
err3:
phy_power_off(cdns->usb2_phy);
err2:
phy_exit(cdns->usb3_phy);
err1:
phy_exit(cdns->usb2_phy);
return ret;
}
/**
* cdns3_remove - unbind drd driver and clean up
* @pdev: Pointer to Linux platform device
*
* Returns 0 on success otherwise negative errno
*/
static int cdns3_remove(struct platform_device *pdev)
{
struct cdns3 *cdns = platform_get_drvdata(pdev);
pm_runtime_get_sync(&pdev->dev);
pm_runtime_disable(&pdev->dev);
pm_runtime_put_noidle(&pdev->dev);
cdns3_exit_roles(cdns);
usb_role_switch_unregister(cdns->role_sw);
phy_power_off(cdns->usb2_phy);
phy_power_off(cdns->usb3_phy);
phy_exit(cdns->usb2_phy);
phy_exit(cdns->usb3_phy);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int cdns3_suspend(struct device *dev)
{
struct cdns3 *cdns = dev_get_drvdata(dev);
unsigned long flags;
if (cdns->role == USB_ROLE_HOST)
return 0;
if (pm_runtime_status_suspended(dev))
pm_runtime_resume(dev);
if (cdns->roles[cdns->role]->suspend) {
spin_lock_irqsave(&cdns->gadget_dev->lock, flags);
cdns->roles[cdns->role]->suspend(cdns, false);
spin_unlock_irqrestore(&cdns->gadget_dev->lock, flags);
}
return 0;
}
static int cdns3_resume(struct device *dev)
{
struct cdns3 *cdns = dev_get_drvdata(dev);
unsigned long flags;
if (cdns->role == USB_ROLE_HOST)
return 0;
if (cdns->roles[cdns->role]->resume) {
spin_lock_irqsave(&cdns->gadget_dev->lock, flags);
cdns->roles[cdns->role]->resume(cdns, false);
spin_unlock_irqrestore(&cdns->gadget_dev->lock, flags);
}
pm_runtime_disable(dev);
pm_runtime_set_active(dev);
pm_runtime_enable(dev);
return 0;
}
#endif
static const struct dev_pm_ops cdns3_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(cdns3_suspend, cdns3_resume)
};
#ifdef CONFIG_OF
static const struct of_device_id of_cdns3_match[] = {
{ .compatible = "cdns,usb3" },
{ },
};
MODULE_DEVICE_TABLE(of, of_cdns3_match);
#endif
static struct platform_driver cdns3_driver = {
.probe = cdns3_probe,
.remove = cdns3_remove,
.driver = {
.name = "cdns-usb3",
.of_match_table = of_match_ptr(of_cdns3_match),
.pm = &cdns3_pm_ops,
},
};
module_platform_driver(cdns3_driver);
MODULE_ALIAS("platform:cdns3");
MODULE_AUTHOR("Pawel Laszczak <pawell@cadence.com>");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("Cadence USB3 DRD Controller Driver");
|