// SPDX-License-Identifier: GPL-2.0
/*
* Cadence USBSS and USBSSP DRD Driver.
*
* Copyright (C) 2018-2020 Cadence.
* Copyright (C) 2019 Texas Instruments
*
* Author: Pawel Laszczak <[email protected]>
* Roger Quadros <[email protected]>
*
*/
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/iopoll.h>
#include <linux/usb/otg.h>
#include "drd.h"
#include "core.h"
/**
* cdns_set_mode - change mode of OTG Core
* @cdns: pointer to context structure
* @mode: selected mode from cdns_role
*
* Returns 0 on success otherwise negative errno
*/
static int cdns_set_mode(struct cdns *cdns, enum usb_dr_mode mode)
{
void __iomem *override_reg;
u32 reg;
switch (mode) {
case USB_DR_MODE_PERIPHERAL:
break;
case USB_DR_MODE_HOST:
break;
case USB_DR_MODE_OTG:
dev_dbg(cdns->dev, "Set controller to OTG mode\n");
if (cdns->version == CDNSP_CONTROLLER_V2)
override_reg = &cdns->otg_cdnsp_regs->override;
else if (cdns->version == CDNS3_CONTROLLER_V1)
override_reg = &cdns->otg_v1_regs->override;
else
override_reg = &cdns->otg_v0_regs->ctrl1;
reg = readl(override_reg);
if (cdns->version != CDNS3_CONTROLLER_V0)
reg |= OVERRIDE_IDPULLUP;
else
reg |= OVERRIDE_IDPULLUP_V0;
writel(reg, override_reg);
if (cdns->version == CDNS3_CONTROLLER_V1) {
/*
* Enable work around feature built into the
* controller to address issue with RX Sensitivity
* est (EL_17) for USB2 PHY. The issue only occures
* for 0x0002450D controller version.
*/
if (cdns->phyrst_a_enable) {
reg = readl(&cdns->otg_v1_regs->phyrst_cfg);
reg |= PHYRST_CFG_PHYRST_A_ENABLE;
writel(reg, &cdns->otg_v1_regs->phyrst_cfg);
}
}
/*
* Hardware specification says: "ID_VALUE must be valid within
* 50ms after idpullup is set to '1" so driver must wait
* 50ms before reading this pin.
*/
usleep_range(50000, 60000);
break;
default:
dev_err(cdns->dev, "Unsupported mode of operation %d\n", mode);
return -EINVAL;
}
return 0;
}
int cdns_get_id(struct cdns *cdns)
{
int id;
id = readl(&cdns->otg_regs->sts) & OTGSTS_ID_VALUE;
dev_dbg(cdns->dev, "OTG ID: %d", id);
return id;
}
int cdns_get_vbus(struct cdns *cdns)
{
int vbus;
vbus = !!(readl(&cdns->otg_regs->sts) & OTGSTS_VBUS_VALID);
dev_dbg(cdns->dev, "OTG VBUS: %d", vbus);
return vbus;
}
void cdns_clear_vbus(struct cdns *cdns)
{
u32 reg;
if (cdns->version != CDNSP_CONTROLLER_V2)
return;
reg = readl(&cdns->otg_cdnsp_regs->override);
reg |= OVERRIDE_SESS_VLD_SEL;
writel(reg, &cdns->otg_cdnsp_regs->override);
}
EXPORT_SYMBOL_GPL(cdns_clear_vbus);
void cdns_set_vbus(struct cdns *cdns)
{
u32 reg;
if (cdns->version != CDNSP_CONTROLLER_V2)
return;
reg = readl(&cdns->otg_cdnsp_regs->override);
reg &= ~OVERRIDE_SESS_VLD_SEL;
writel(reg, &cdns->otg_cdnsp_regs->override);
}
EXPORT_SYMBOL_GPL(cdns_set_vbus);
bool cdns_is_host(struct cdns *cdns)
{
if (cdns->dr_mode == USB_DR_MODE_HOST)
return true;
else if (cdns_get_id(cdns) == CDNS3_ID_HOST)
return true;
return false;
}
bool cdns_is_device(struct cdns *cdns)
{
if (cdns->dr_mode == USB_DR_MODE_PERIPHERAL)
return true;
else if (cdns->dr_mode == USB_DR_MODE_OTG)
if (cdns_get_id(cdns) == CDNS3_ID_PERIPHERAL)
return true;
return false;
}
/**
* cdns_otg_disable_irq - Disable all OTG interrupts
* @cdns: Pointer to controller context structure
*/
static void cdns_otg_disable_irq(struct cdns *cdns)
{
if (cdns->version)
writel(0, &cdns->otg_irq_regs->ien);
}
/**
* cdns_otg_enable_irq - enable id and sess_valid interrupts
* @cdns: Pointer to controller context structure
*/
static void cdns_otg_enable_irq(struct cdns *cdns)
{
writel(OTGIEN_ID_CHANGE_INT | OTGIEN_VBUSVALID_RISE_INT |
OTGIEN_VBUSVALID_FALL_INT, &cdns->otg_irq_regs->ien);
}
/**
* cdns_drd_host_on - start host.
* @cdns: Pointer to controller context structure.
*
* Returns 0 on success otherwise negative errno.
*/
int cdns_drd_host_on(struct cdns *cdns)
{
u32 val, ready_bit;
int ret;
/* Enable host mode. */
writel(OTGCMD_HOST_BUS_REQ | OTGCMD_OTG_DIS,
&cdns->otg_regs->cmd);
if (cdns->version == CDNSP_CONTROLLER_V2)
ready_bit = OTGSTS_CDNSP_XHCI_READY;
else
ready_bit = OTGSTS_CDNS3_XHCI_READY;
dev_dbg(cdns->dev, "Waiting till Host mode is turned on\n");
ret = readl_poll_timeout_atomic(&cdns->otg_regs->sts, val,
val & ready_bit, 1, 100000);
if (ret)
dev_err(cdns->dev, "timeout waiting for xhci_ready\n");
phy_set_mode(cdns->usb2_phy, PHY_MODE_USB_HOST);
phy_set_mode(cdns->usb3_phy, PHY_MODE_USB_HOST);
return ret;
}
/**
* cdns_drd_host_off - stop host.
* @cdns: Pointer to controller context structure.
*/
void cdns_drd_host_off(struct cdns *cdns)
{
u32 val;
writel(OTGCMD_HOST_BUS_DROP | OTGCMD_DEV_BUS_DROP |
OTGCMD_DEV_POWER_OFF | OTGCMD_HOST_POWER_OFF,
&cdns->otg_regs->cmd);
/* Waiting till H_IDLE state.*/
readl_poll_timeout_atomic(&cdns->otg_regs->state, val,
!(val & OTGSTATE_HOST_STATE_MASK),
1, 2000000);
phy_set_mode(cdns->usb2_phy, PHY_MODE_INVALID);
phy_set_mode(cdns->usb3_phy, PHY_MODE_INVALID);
}
/**
* cdns_drd_gadget_on - start gadget.
* @cdns: Pointer to controller context structure.
*
* Returns 0 on success otherwise negative errno
*/
int cdns_drd_gadget_on(struct cdns *cdns)
{
u32 reg = OTGCMD_OTG_DIS;
u32 ready_bit;
int ret, val;
/* switch OTG core */
writel(OTGCMD_DEV_BUS_REQ | reg, &cdns->otg_regs->cmd);
dev_dbg(cdns->dev, "Waiting till Device mode is turned on\n");
if (cdns->version == CDNSP_CONTROLLER_V2)
ready_bit = OTGSTS_CDNSP_DEV_READY;
else
ready_bit = OTGSTS_CDNS3_DEV_READY;
ret = readl_poll_timeout_atomic(&cdns->otg_regs->sts, val,
val & ready_bit, 1, 100000);
if (ret) {
dev_err(cdns->dev, "timeout waiting for dev_ready\n");
return ret;
}
phy_set_mode(cdns->usb2_phy, PHY_MODE_USB_DEVICE);
phy_set_mode(cdns->usb3_phy, PHY_MODE_USB_DEVICE);
return 0;
}
EXPORT_SYMBOL_GPL(cdns_drd_gadget_on);
/**
* cdns_drd_gadget_off - stop gadget.
* @cdns: Pointer to controller context structure.
*/
void cdns_drd_gadget_off(struct cdns *cdns)
{
u32 val;
/*
* Driver should wait at least 10us after disabling Device
* before turning-off Device (DEV_BUS_DROP).
*/
usleep_range(20, 30);
writel(OTGCMD_HOST_BUS_DROP | OTGCMD_DEV_BUS_DROP |
OTGCMD_DEV_POWER_OFF | OTGCMD_HOST_POWER_OFF,
&cdns->otg_regs->cmd);
/* Waiting till DEV_IDLE state.*/
readl_poll_timeout_atomic(&cdns->otg_regs->state, val,
!(val & OTGSTATE_DEV_STATE_MASK),
1, 2000000);
phy_set_mode(cdns->usb2_phy, PHY_MODE_INVALID);
phy_set_mode(cdns->usb3_phy, PHY_MODE_INVALID);
}
EXPORT_SYMBOL_GPL(cdns_drd_gadget_off);
/**
* cdns_init_otg_mode - initialize drd controller
* @cdns: Pointer to controller context structure
*
* Returns 0 on success otherwise negative errno
*/
static int cdns_init_otg_mode(struct cdns *cdns)
{
int ret;
cdns_otg_disable_irq(cdns);
/* clear all interrupts */
writel(~0, &cdns->otg_irq_regs->ivect);
ret = cdns_set_mode(cdns, USB_DR_MODE_OTG);
if (ret)
return ret;
cdns_otg_enable_irq(cdns);
return 0;
}
/**
* cdns_drd_update_mode - initialize mode of operation
* @cdns: Pointer to controller context structure
*
* Returns 0 on success otherwise negative errno
*/
int cdns_drd_update_mode(struct cdns *cdns)
{
int ret;
switch (cdns->dr_mode) {
case USB_DR_MODE_PERIPHERAL:
ret = cdns_set_mode(cdns, USB_DR_MODE_PERIPHERAL);
break;
case USB_DR_MODE_HOST:
ret = cdns_set_mode(cdns, USB_DR_MODE_HOST);
break;
case USB_DR_MODE_OTG:
ret = cdns_init_otg_mode(cdns);
break;
default:
dev_err(cdns->dev, "Unsupported mode of operation %d\n",
cdns->dr_mode);
return -EINVAL;
}
return ret;
}
static irqreturn_t cdns_drd_thread_irq(int irq, void *data)
{
struct cdns *cdns = data;
cdns_hw_role_switch(cdns);
return IRQ_HANDLED;
}
/**
* cdns_drd_irq - interrupt handler for OTG events
*
* @irq: irq number for cdns core device
* @data: structure of cdns
*
* Returns IRQ_HANDLED or IRQ_NONE
*/
static irqreturn_t cdns_drd_irq(int irq, void *data)
{
irqreturn_t ret = IRQ_NONE;
struct cdns *cdns = data;
u32 reg;
if (cdns->dr_mode != USB_DR_MODE_OTG)
return IRQ_NONE;
if (cdns->in_lpm)
return ret;
reg = readl(&cdns->otg_irq_regs->ivect);
if (!reg)
return IRQ_NONE;
if (reg & OTGIEN_ID_CHANGE_INT) {
dev_dbg(cdns->dev, "OTG IRQ: new ID: %d\n",
cdns_get_id(cdns));
ret = IRQ_WAKE_THREAD;
}
if (reg & (OTGIEN_VBUSVALID_RISE_INT | OTGIEN_VBUSVALID_FALL_INT)) {
dev_dbg(cdns->dev, "OTG IRQ: new VBUS: %d\n",
cdns_get_vbus(cdns));
ret = IRQ_WAKE_THREAD;
}
writel(~0, &cdns->otg_irq_regs->ivect);
return ret;
}
int cdns_drd_init(struct cdns *cdns)
{
void __iomem *regs;
u32 state, reg;
int ret;
regs = devm_ioremap_resource(cdns->dev, &cdns->otg_res);
if (IS_ERR(regs))
return PTR_ERR(regs);
/* Detection of DRD version. Controller has been released
* in three versions. All are very similar and are software compatible,
* but they have same changes in register maps.
* The first register in oldest version is command register and it's
* read only. Driver should read 0 from it. On the other hand, in v1
* and v2 the first register contains device ID number which is not
* set to 0. Driver uses this fact to detect the proper version of
* controller.
*/
cdns->otg_v0_regs = regs;
if (!readl(&cdns->otg_v0_regs->cmd)) {
cdns->version = CDNS3_CONTROLLER_V0;
cdns->otg_v1_regs = NULL;
cdns->otg_cdnsp_regs = NULL;
cdns->otg_regs = regs;
cdns->otg_irq_regs = (struct cdns_otg_irq_regs __iomem *)
&cdns->otg_v0_regs->ien;
writel(1, &cdns->otg_v0_regs->simulate);
dev_dbg(cdns->dev, "DRD version v0 (%08x)\n",
readl(&cdns->otg_v0_regs->version));
} else {
cdns->otg_v0_regs = NULL;
cdns->otg_v1_regs = regs;
cdns->otg_cdnsp_regs = regs;
cdns->otg_regs = (void __iomem *)&cdns->otg_v1_regs->cmd;
state = readl(&cdns->otg_cdnsp_regs->did);
if (OTG_CDNSP_CHECK_DID(state)) {
cdns->otg_irq_regs = (struct cdns_otg_irq_regs __iomem *)
&cdns->otg_cdnsp_regs->ien;
cdns->version = CDNSP_CONTROLLER_V2;
} else if (OTG_CDNS3_CHECK_DID(state)) {
cdns->otg_irq_regs = (struct cdns_otg_irq_regs __iomem *)
&cdns->otg_v1_regs->ien;
writel(1, &cdns->otg_v1_regs->simulate);
if (cdns->pdata &&
(cdns->pdata->quirks & CDNS3_DRD_SUSPEND_RESIDENCY_ENABLE)) {
reg = readl(&cdns->otg_v1_regs->susp_ctrl);
reg |= SUSP_CTRL_SUSPEND_RESIDENCY_ENABLE;
writel(reg, &cdns->otg_v1_regs->susp_ctrl);
}
cdns->version = CDNS3_CONTROLLER_V1;
} else {
dev_err(cdns->dev, "not supported DID=0x%08x\n", state);
return -EINVAL;
}
dev_dbg(cdns->dev, "DRD version v1 (ID: %08x, rev: %08x)\n",
readl(&cdns->otg_v1_regs->did),
readl(&cdns->otg_v1_regs->rid));
}
state = OTGSTS_STRAP(readl(&cdns->otg_regs->sts));
/* Update dr_mode according to STRAP configuration. */
cdns->dr_mode = USB_DR_MODE_OTG;
if ((cdns->version == CDNSP_CONTROLLER_V2 &&
state == OTGSTS_CDNSP_STRAP_HOST) ||
(cdns->version != CDNSP_CONTROLLER_V2 &&
state == OTGSTS_STRAP_HOST)) {
dev_dbg(cdns->dev, "Controller strapped to HOST\n");
cdns->dr_mode = USB_DR_MODE_HOST;
} else if ((cdns->version == CDNSP_CONTROLLER_V2 &&
state == OTGSTS_CDNSP_STRAP_GADGET) ||
(cdns->version != CDNSP_CONTROLLER_V2 &&
state == OTGSTS_STRAP_GADGET)) {
dev_dbg(cdns->dev, "Controller strapped to PERIPHERAL\n");
cdns->dr_mode = USB_DR_MODE_PERIPHERAL;
}
ret = devm_request_threaded_irq(cdns->dev, cdns->otg_irq,
cdns_drd_irq,
cdns_drd_thread_irq,
IRQF_SHARED,
dev_name(cdns->dev), cdns);
if (ret) {
dev_err(cdns->dev, "couldn't get otg_irq\n");
return ret;
}
state = readl(&cdns->otg_regs->sts);
if (OTGSTS_OTG_NRDY(state)) {
dev_err(cdns->dev, "Cadence USB3 OTG device not ready\n");
return -ENODEV;
}
return 0;
}
int cdns_drd_exit(struct cdns *cdns)
{
cdns_otg_disable_irq(cdns);
return 0;
}
/* Indicate the cdns3 core was power lost before */
bool cdns_power_is_lost(struct cdns *cdns)
{
if (cdns->version == CDNS3_CONTROLLER_V0) {
if (!(readl(&cdns->otg_v0_regs->simulate) & BIT(0)))
return true;
} else {
if (!(readl(&cdns->otg_v1_regs->simulate) & BIT(0)))
return true;
}
return false;
}
EXPORT_SYMBOL_GPL(cdns_power_is_lost);
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