tegrakernel/kernel/kernel-4.9/drivers/usb/dwc3/gadget.c

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2022-02-16 09:13:02 -06:00
/**
* gadget.c - DesignWare USB3 DRD Controller Gadget Framework Link
*
* Copyright (C) 2010-2011 Texas Instruments Incorporated - http://www.ti.com
*
* Authors: Felipe Balbi <balbi@ti.com>,
* Sebastian Andrzej Siewior <bigeasy@linutronix.de>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 of
* the License 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.
*/
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/list.h>
#include <linux/dma-mapping.h>
#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>
#include "debug.h"
#include "core.h"
#include "gadget.h"
#include "io.h"
/**
* dwc3_gadget_set_test_mode - Enables USB2 Test Modes
* @dwc: pointer to our context structure
* @mode: the mode to set (J, K SE0 NAK, Force Enable)
*
* Caller should take care of locking. This function will
* return 0 on success or -EINVAL if wrong Test Selector
* is passed
*/
int dwc3_gadget_set_test_mode(struct dwc3 *dwc, int mode)
{
u32 reg;
reg = dwc3_readl(dwc->regs, DWC3_DCTL);
reg &= ~DWC3_DCTL_TSTCTRL_MASK;
switch (mode) {
case TEST_J:
case TEST_K:
case TEST_SE0_NAK:
case TEST_PACKET:
case TEST_FORCE_EN:
reg |= mode << 1;
break;
default:
return -EINVAL;
}
dwc3_writel(dwc->regs, DWC3_DCTL, reg);
return 0;
}
/**
* dwc3_gadget_get_link_state - Gets current state of USB Link
* @dwc: pointer to our context structure
*
* Caller should take care of locking. This function will
* return the link state on success (>= 0) or -ETIMEDOUT.
*/
int dwc3_gadget_get_link_state(struct dwc3 *dwc)
{
u32 reg;
reg = dwc3_readl(dwc->regs, DWC3_DSTS);
return DWC3_DSTS_USBLNKST(reg);
}
/**
* dwc3_gadget_set_link_state - Sets USB Link to a particular State
* @dwc: pointer to our context structure
* @state: the state to put link into
*
* Caller should take care of locking. This function will
* return 0 on success or -ETIMEDOUT.
*/
int dwc3_gadget_set_link_state(struct dwc3 *dwc, enum dwc3_link_state state)
{
int retries = 10000;
u32 reg;
/*
* Wait until device controller is ready. Only applies to 1.94a and
* later RTL.
*/
if (dwc->revision >= DWC3_REVISION_194A) {
while (--retries) {
reg = dwc3_readl(dwc->regs, DWC3_DSTS);
if (reg & DWC3_DSTS_DCNRD)
udelay(5);
else
break;
}
if (retries <= 0)
return -ETIMEDOUT;
}
reg = dwc3_readl(dwc->regs, DWC3_DCTL);
reg &= ~DWC3_DCTL_ULSTCHNGREQ_MASK;
/* set requested state */
reg |= DWC3_DCTL_ULSTCHNGREQ(state);
dwc3_writel(dwc->regs, DWC3_DCTL, reg);
/*
* The following code is racy when called from dwc3_gadget_wakeup,
* and is not needed, at least on newer versions
*/
if (dwc->revision >= DWC3_REVISION_194A)
return 0;
/* wait for a change in DSTS */
retries = 10000;
while (--retries) {
reg = dwc3_readl(dwc->regs, DWC3_DSTS);
if (DWC3_DSTS_USBLNKST(reg) == state)
return 0;
udelay(5);
}
dwc3_trace(trace_dwc3_gadget,
"link state change request timed out");
return -ETIMEDOUT;
}
/**
* dwc3_ep_inc_trb() - Increment a TRB index.
* @index - Pointer to the TRB index to increment.
*
* The index should never point to the link TRB. After incrementing,
* if it is point to the link TRB, wrap around to the beginning. The
* link TRB is always at the last TRB entry.
*/
static void dwc3_ep_inc_trb(u8 *index)
{
(*index)++;
if (*index == (DWC3_TRB_NUM - 1))
*index = 0;
}
static void dwc3_ep_inc_enq(struct dwc3_ep *dep)
{
dwc3_ep_inc_trb(&dep->trb_enqueue);
}
static void dwc3_ep_inc_deq(struct dwc3_ep *dep)
{
dwc3_ep_inc_trb(&dep->trb_dequeue);
}
void dwc3_gadget_giveback(struct dwc3_ep *dep, struct dwc3_request *req,
int status)
{
struct dwc3 *dwc = dep->dwc;
unsigned int unmap_after_complete = false;
req->started = false;
list_del(&req->list);
req->trb = NULL;
if (req->request.status == -EINPROGRESS)
req->request.status = status;
/*
* NOTICE we don't want to unmap before calling ->complete() if we're
* dealing with a bounced ep0 request. If we unmap it here, we would end
* up overwritting the contents of req->buf and this could confuse the
* gadget driver.
*/
if (dwc->ep0_bounced && dep->number <= 1) {
dwc->ep0_bounced = false;
unmap_after_complete = true;
} else {
usb_gadget_unmap_request(&dwc->gadget,
&req->request, req->direction);
}
trace_dwc3_gadget_giveback(req);
spin_unlock(&dwc->lock);
usb_gadget_giveback_request(&dep->endpoint, &req->request);
spin_lock(&dwc->lock);
if (unmap_after_complete)
usb_gadget_unmap_request(&dwc->gadget,
&req->request, req->direction);
if (dep->number > 1)
pm_runtime_put(dwc->dev);
}
int dwc3_send_gadget_generic_command(struct dwc3 *dwc, unsigned cmd, u32 param)
{
u32 timeout = 500;
int status = 0;
int ret = 0;
u32 reg;
dwc3_writel(dwc->regs, DWC3_DGCMDPAR, param);
dwc3_writel(dwc->regs, DWC3_DGCMD, cmd | DWC3_DGCMD_CMDACT);
do {
reg = dwc3_readl(dwc->regs, DWC3_DGCMD);
if (!(reg & DWC3_DGCMD_CMDACT)) {
status = DWC3_DGCMD_STATUS(reg);
if (status)
ret = -EINVAL;
break;
}
} while (timeout--);
if (!timeout) {
ret = -ETIMEDOUT;
status = -ETIMEDOUT;
}
trace_dwc3_gadget_generic_cmd(cmd, param, status);
return ret;
}
static int __dwc3_gadget_wakeup(struct dwc3 *dwc);
int dwc3_send_gadget_ep_cmd(struct dwc3_ep *dep, unsigned cmd,
struct dwc3_gadget_ep_cmd_params *params)
{
struct dwc3 *dwc = dep->dwc;
u32 timeout = 1000;
u32 reg;
int cmd_status = 0;
int susphy = false;
int ret = -EINVAL;
/*
* Synopsys Databook 2.60a states, on section 6.3.2.5.[1-8], that if
* we're issuing an endpoint command, we must check if
* GUSB2PHYCFG.SUSPHY bit is set. If it is, then we need to clear it.
*
* We will also set SUSPHY bit to what it was before returning as stated
* by the same section on Synopsys databook.
*/
if (dwc->gadget.speed <= USB_SPEED_HIGH) {
reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0));
if (unlikely(reg & DWC3_GUSB2PHYCFG_SUSPHY)) {
susphy = true;
reg &= ~DWC3_GUSB2PHYCFG_SUSPHY;
dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg);
}
}
if (cmd == DWC3_DEPCMD_STARTTRANSFER) {
int needs_wakeup;
needs_wakeup = (dwc->link_state == DWC3_LINK_STATE_U1 ||
dwc->link_state == DWC3_LINK_STATE_U2 ||
dwc->link_state == DWC3_LINK_STATE_U3);
if (unlikely(needs_wakeup)) {
ret = __dwc3_gadget_wakeup(dwc);
dev_WARN_ONCE(dwc->dev, ret, "wakeup failed --> %d\n",
ret);
}
}
dwc3_writel(dep->regs, DWC3_DEPCMDPAR0, params->param0);
dwc3_writel(dep->regs, DWC3_DEPCMDPAR1, params->param1);
dwc3_writel(dep->regs, DWC3_DEPCMDPAR2, params->param2);
dwc3_writel(dep->regs, DWC3_DEPCMD, cmd | DWC3_DEPCMD_CMDACT);
do {
reg = dwc3_readl(dep->regs, DWC3_DEPCMD);
if (!(reg & DWC3_DEPCMD_CMDACT)) {
cmd_status = DWC3_DEPCMD_STATUS(reg);
switch (cmd_status) {
case 0:
ret = 0;
break;
case DEPEVT_TRANSFER_NO_RESOURCE:
ret = -EINVAL;
break;
case DEPEVT_TRANSFER_BUS_EXPIRY:
/*
* SW issues START TRANSFER command to
* isochronous ep with future frame interval. If
* future interval time has already passed when
* core receives the command, it will respond
* with an error status of 'Bus Expiry'.
*
* Instead of always returning -EINVAL, let's
* give a hint to the gadget driver that this is
* the case by returning -EAGAIN.
*/
ret = -EAGAIN;
break;
default:
dev_WARN(dwc->dev, "UNKNOWN cmd status\n");
}
break;
}
} while (--timeout);
if (timeout == 0) {
ret = -ETIMEDOUT;
cmd_status = -ETIMEDOUT;
}
trace_dwc3_gadget_ep_cmd(dep, cmd, params, cmd_status);
if (unlikely(susphy)) {
reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0));
reg |= DWC3_GUSB2PHYCFG_SUSPHY;
dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg);
}
return ret;
}
static int dwc3_send_clear_stall_ep_cmd(struct dwc3_ep *dep)
{
struct dwc3 *dwc = dep->dwc;
struct dwc3_gadget_ep_cmd_params params;
u32 cmd = DWC3_DEPCMD_CLEARSTALL;
/*
* As of core revision 2.60a the recommended programming model
* is to set the ClearPendIN bit when issuing a Clear Stall EP
* command for IN endpoints. This is to prevent an issue where
* some (non-compliant) hosts may not send ACK TPs for pending
* IN transfers due to a mishandled error condition. Synopsys
* STAR 9000614252.
*/
if (dep->direction && (dwc->revision >= DWC3_REVISION_260A) &&
(dwc->gadget.speed >= USB_SPEED_SUPER))
cmd |= DWC3_DEPCMD_CLEARPENDIN;
memset(&params, 0, sizeof(params));
return dwc3_send_gadget_ep_cmd(dep, cmd, &params);
}
static dma_addr_t dwc3_trb_dma_offset(struct dwc3_ep *dep,
struct dwc3_trb *trb)
{
u32 offset = (char *) trb - (char *) dep->trb_pool;
return dep->trb_pool_dma + offset;
}
static int dwc3_alloc_trb_pool(struct dwc3_ep *dep)
{
struct dwc3 *dwc = dep->dwc;
if (dep->trb_pool)
return 0;
dep->trb_pool = dma_alloc_coherent(dwc->dev,
sizeof(struct dwc3_trb) * DWC3_TRB_NUM,
&dep->trb_pool_dma, GFP_KERNEL);
if (!dep->trb_pool) {
dev_err(dep->dwc->dev, "failed to allocate trb pool for %s\n",
dep->name);
return -ENOMEM;
}
return 0;
}
static void dwc3_free_trb_pool(struct dwc3_ep *dep)
{
struct dwc3 *dwc = dep->dwc;
dma_free_coherent(dwc->dev, sizeof(struct dwc3_trb) * DWC3_TRB_NUM,
dep->trb_pool, dep->trb_pool_dma);
dep->trb_pool = NULL;
dep->trb_pool_dma = 0;
}
static int dwc3_gadget_set_xfer_resource(struct dwc3 *dwc, struct dwc3_ep *dep);
/**
* dwc3_gadget_start_config - Configure EP resources
* @dwc: pointer to our controller context structure
* @dep: endpoint that is being enabled
*
* The assignment of transfer resources cannot perfectly follow the
* data book due to the fact that the controller driver does not have
* all knowledge of the configuration in advance. It is given this
* information piecemeal by the composite gadget framework after every
* SET_CONFIGURATION and SET_INTERFACE. Trying to follow the databook
* programming model in this scenario can cause errors. For two
* reasons:
*
* 1) The databook says to do DEPSTARTCFG for every SET_CONFIGURATION
* and SET_INTERFACE (8.1.5). This is incorrect in the scenario of
* multiple interfaces.
*
* 2) The databook does not mention doing more DEPXFERCFG for new
* endpoint on alt setting (8.1.6).
*
* The following simplified method is used instead:
*
* All hardware endpoints can be assigned a transfer resource and this
* setting will stay persistent until either a core reset or
* hibernation. So whenever we do a DEPSTARTCFG(0) we can go ahead and
* do DEPXFERCFG for every hardware endpoint as well. We are
* guaranteed that there are as many transfer resources as endpoints.
*
* This function is called for each endpoint when it is being enabled
* but is triggered only when called for EP0-out, which always happens
* first, and which should only happen in one of the above conditions.
*/
static int dwc3_gadget_start_config(struct dwc3 *dwc, struct dwc3_ep *dep)
{
struct dwc3_gadget_ep_cmd_params params;
u32 cmd;
int i;
int ret;
if (dep->number)
return 0;
memset(&params, 0x00, sizeof(params));
cmd = DWC3_DEPCMD_DEPSTARTCFG;
ret = dwc3_send_gadget_ep_cmd(dep, cmd, &params);
if (ret)
return ret;
for (i = 0; i < DWC3_ENDPOINTS_NUM; i++) {
struct dwc3_ep *dep = dwc->eps[i];
if (!dep)
continue;
ret = dwc3_gadget_set_xfer_resource(dwc, dep);
if (ret)
return ret;
}
return 0;
}
static int dwc3_gadget_set_ep_config(struct dwc3 *dwc, struct dwc3_ep *dep,
const struct usb_endpoint_descriptor *desc,
const struct usb_ss_ep_comp_descriptor *comp_desc,
bool modify, bool restore)
{
struct dwc3_gadget_ep_cmd_params params;
if (dev_WARN_ONCE(dwc->dev, modify && restore,
"Can't modify and restore\n"))
return -EINVAL;
memset(&params, 0x00, sizeof(params));
params.param0 = DWC3_DEPCFG_EP_TYPE(usb_endpoint_type(desc))
| DWC3_DEPCFG_MAX_PACKET_SIZE(usb_endpoint_maxp(desc));
/* Burst size is only needed in SuperSpeed mode */
if (dwc->gadget.speed >= USB_SPEED_SUPER) {
u32 burst = dep->endpoint.maxburst;
params.param0 |= DWC3_DEPCFG_BURST_SIZE(burst - 1);
}
if (modify) {
params.param0 |= DWC3_DEPCFG_ACTION_MODIFY;
} else if (restore) {
params.param0 |= DWC3_DEPCFG_ACTION_RESTORE;
params.param2 |= dep->saved_state;
} else {
params.param0 |= DWC3_DEPCFG_ACTION_INIT;
}
if (usb_endpoint_xfer_control(desc))
params.param1 = DWC3_DEPCFG_XFER_COMPLETE_EN;
if (dep->number <= 1 || usb_endpoint_xfer_isoc(desc))
params.param1 |= DWC3_DEPCFG_XFER_NOT_READY_EN;
if (usb_ss_max_streams(comp_desc) && usb_endpoint_xfer_bulk(desc)) {
params.param1 |= DWC3_DEPCFG_STREAM_CAPABLE
| DWC3_DEPCFG_STREAM_EVENT_EN;
dep->stream_capable = true;
}
if (!usb_endpoint_xfer_control(desc))
params.param1 |= DWC3_DEPCFG_XFER_IN_PROGRESS_EN;
/*
* We are doing 1:1 mapping for endpoints, meaning
* Physical Endpoints 2 maps to Logical Endpoint 2 and
* so on. We consider the direction bit as part of the physical
* endpoint number. So USB endpoint 0x81 is 0x03.
*/
params.param1 |= DWC3_DEPCFG_EP_NUMBER(dep->number);
/*
* We must use the lower 16 TX FIFOs even though
* HW might have more
*/
if (dep->direction)
params.param0 |= DWC3_DEPCFG_FIFO_NUMBER(dep->number >> 1);
if (desc->bInterval) {
params.param1 |= DWC3_DEPCFG_BINTERVAL_M1(desc->bInterval - 1);
dep->interval = 1 << (desc->bInterval - 1);
}
return dwc3_send_gadget_ep_cmd(dep, DWC3_DEPCMD_SETEPCONFIG, &params);
}
static int dwc3_gadget_set_xfer_resource(struct dwc3 *dwc, struct dwc3_ep *dep)
{
struct dwc3_gadget_ep_cmd_params params;
memset(&params, 0x00, sizeof(params));
params.param0 = DWC3_DEPXFERCFG_NUM_XFER_RES(1);
return dwc3_send_gadget_ep_cmd(dep, DWC3_DEPCMD_SETTRANSFRESOURCE,
&params);
}
/**
* __dwc3_gadget_ep_enable - Initializes a HW endpoint
* @dep: endpoint to be initialized
* @desc: USB Endpoint Descriptor
*
* Caller should take care of locking
*/
static int __dwc3_gadget_ep_enable(struct dwc3_ep *dep,
const struct usb_endpoint_descriptor *desc,
const struct usb_ss_ep_comp_descriptor *comp_desc,
bool modify, bool restore)
{
struct dwc3 *dwc = dep->dwc;
u32 reg;
int ret;
dwc3_trace(trace_dwc3_gadget, "Enabling %s", dep->name);
if (!(dep->flags & DWC3_EP_ENABLED)) {
ret = dwc3_gadget_start_config(dwc, dep);
if (ret)
return ret;
}
ret = dwc3_gadget_set_ep_config(dwc, dep, desc, comp_desc, modify,
restore);
if (ret)
return ret;
if (!(dep->flags & DWC3_EP_ENABLED)) {
struct dwc3_trb *trb_st_hw;
struct dwc3_trb *trb_link;
dep->endpoint.desc = desc;
dep->comp_desc = comp_desc;
dep->type = usb_endpoint_type(desc);
dep->flags |= DWC3_EP_ENABLED;
reg = dwc3_readl(dwc->regs, DWC3_DALEPENA);
reg |= DWC3_DALEPENA_EP(dep->number);
dwc3_writel(dwc->regs, DWC3_DALEPENA, reg);
if (usb_endpoint_xfer_control(desc))
return 0;
/* Initialize the TRB ring */
dep->trb_dequeue = 0;
dep->trb_enqueue = 0;
memset(dep->trb_pool, 0,
sizeof(struct dwc3_trb) * DWC3_TRB_NUM);
/* Link TRB. The HWO bit is never reset */
trb_st_hw = &dep->trb_pool[0];
trb_link = &dep->trb_pool[DWC3_TRB_NUM - 1];
trb_link->bpl = lower_32_bits(dwc3_trb_dma_offset(dep, trb_st_hw));
trb_link->bph = upper_32_bits(dwc3_trb_dma_offset(dep, trb_st_hw));
trb_link->ctrl |= DWC3_TRBCTL_LINK_TRB;
trb_link->ctrl |= DWC3_TRB_CTRL_HWO;
}
return 0;
}
static void dwc3_stop_active_transfer(struct dwc3 *dwc, u32 epnum, bool force);
static void dwc3_remove_requests(struct dwc3 *dwc, struct dwc3_ep *dep)
{
struct dwc3_request *req;
dwc3_stop_active_transfer(dwc, dep->number, true);
/* - giveback all requests to gadget driver */
while (!list_empty(&dep->started_list)) {
req = next_request(&dep->started_list);
dwc3_gadget_giveback(dep, req, -ESHUTDOWN);
}
while (!list_empty(&dep->pending_list)) {
req = next_request(&dep->pending_list);
dwc3_gadget_giveback(dep, req, -ESHUTDOWN);
}
}
/**
* __dwc3_gadget_ep_disable - Disables a HW endpoint
* @dep: the endpoint to disable
*
* This function also removes requests which are currently processed ny the
* hardware and those which are not yet scheduled.
* Caller should take care of locking.
*/
static int __dwc3_gadget_ep_disable(struct dwc3_ep *dep)
{
struct dwc3 *dwc = dep->dwc;
u32 reg;
dwc3_trace(trace_dwc3_gadget, "Disabling %s", dep->name);
dwc3_remove_requests(dwc, dep);
/* make sure HW endpoint isn't stalled */
if (dep->flags & DWC3_EP_STALL)
__dwc3_gadget_ep_set_halt(dep, 0, false);
reg = dwc3_readl(dwc->regs, DWC3_DALEPENA);
reg &= ~DWC3_DALEPENA_EP(dep->number);
dwc3_writel(dwc->regs, DWC3_DALEPENA, reg);
dep->stream_capable = false;
dep->endpoint.desc = NULL;
dep->comp_desc = NULL;
dep->type = 0;
dep->flags = 0;
return 0;
}
/* -------------------------------------------------------------------------- */
static int dwc3_gadget_ep0_enable(struct usb_ep *ep,
const struct usb_endpoint_descriptor *desc)
{
return -EINVAL;
}
static int dwc3_gadget_ep0_disable(struct usb_ep *ep)
{
return -EINVAL;
}
/* -------------------------------------------------------------------------- */
static int dwc3_gadget_ep_enable(struct usb_ep *ep,
const struct usb_endpoint_descriptor *desc)
{
struct dwc3_ep *dep;
struct dwc3 *dwc;
unsigned long flags;
int ret;
if (!ep || !desc || desc->bDescriptorType != USB_DT_ENDPOINT) {
pr_debug("dwc3: invalid parameters\n");
return -EINVAL;
}
if (!desc->wMaxPacketSize) {
pr_debug("dwc3: missing wMaxPacketSize\n");
return -EINVAL;
}
dep = to_dwc3_ep(ep);
dwc = dep->dwc;
if (dev_WARN_ONCE(dwc->dev, dep->flags & DWC3_EP_ENABLED,
"%s is already enabled\n",
dep->name))
return 0;
spin_lock_irqsave(&dwc->lock, flags);
ret = __dwc3_gadget_ep_enable(dep, desc, ep->comp_desc, false, false);
spin_unlock_irqrestore(&dwc->lock, flags);
return ret;
}
static int dwc3_gadget_ep_disable(struct usb_ep *ep)
{
struct dwc3_ep *dep;
struct dwc3 *dwc;
unsigned long flags;
int ret;
if (!ep) {
pr_debug("dwc3: invalid parameters\n");
return -EINVAL;
}
dep = to_dwc3_ep(ep);
dwc = dep->dwc;
if (dev_WARN_ONCE(dwc->dev, !(dep->flags & DWC3_EP_ENABLED),
"%s is already disabled\n",
dep->name))
return 0;
spin_lock_irqsave(&dwc->lock, flags);
ret = __dwc3_gadget_ep_disable(dep);
spin_unlock_irqrestore(&dwc->lock, flags);
return ret;
}
static struct usb_request *dwc3_gadget_ep_alloc_request(struct usb_ep *ep,
gfp_t gfp_flags)
{
struct dwc3_request *req;
struct dwc3_ep *dep = to_dwc3_ep(ep);
req = kzalloc(sizeof(*req), gfp_flags);
if (!req)
return NULL;
req->epnum = dep->number;
req->dep = dep;
dep->allocated_requests++;
trace_dwc3_alloc_request(req);
return &req->request;
}
static void dwc3_gadget_ep_free_request(struct usb_ep *ep,
struct usb_request *request)
{
struct dwc3_request *req = to_dwc3_request(request);
struct dwc3_ep *dep = to_dwc3_ep(ep);
dep->allocated_requests--;
trace_dwc3_free_request(req);
kfree(req);
}
static u32 dwc3_calc_trbs_left(struct dwc3_ep *dep);
/**
* dwc3_prepare_one_trb - setup one TRB from one request
* @dep: endpoint for which this request is prepared
* @req: dwc3_request pointer
*/
static void dwc3_prepare_one_trb(struct dwc3_ep *dep,
struct dwc3_request *req, dma_addr_t dma,
unsigned length, unsigned chain, unsigned node)
{
struct dwc3_trb *trb;
struct dwc3 *dwc = dep->dwc;
struct usb_gadget *gadget = &dwc->gadget;
enum usb_device_speed speed = gadget->speed;
dwc3_trace(trace_dwc3_gadget, "%s: req %p dma %08llx length %d%s",
dep->name, req, (unsigned long long) dma,
length, chain ? " chain" : "");
trb = &dep->trb_pool[dep->trb_enqueue];
if (!req->trb) {
dwc3_gadget_move_started_request(req);
req->trb = trb;
req->trb_dma = dwc3_trb_dma_offset(dep, trb);
req->first_trb_index = dep->trb_enqueue;
dep->queued_requests++;
}
dwc3_ep_inc_enq(dep);
trb->size = DWC3_TRB_SIZE_LENGTH(length);
trb->bpl = lower_32_bits(dma);
trb->bph = upper_32_bits(dma);
switch (usb_endpoint_type(dep->endpoint.desc)) {
case USB_ENDPOINT_XFER_CONTROL:
trb->ctrl = DWC3_TRBCTL_CONTROL_SETUP;
break;
case USB_ENDPOINT_XFER_ISOC:
if (!node) {
trb->ctrl = DWC3_TRBCTL_ISOCHRONOUS_FIRST;
/*
* USB Specification 2.0 Section 5.9.2 states that: "If
* there is only a single transaction in the microframe,
* only a DATA0 data packet PID is used. If there are
* two transactions per microframe, DATA1 is used for
* the first transaction data packet and DATA0 is used
* for the second transaction data packet. If there are
* three transactions per microframe, DATA2 is used for
* the first transaction data packet, DATA1 is used for
* the second, and DATA0 is used for the third."
*
* IOW, we should satisfy the following cases:
*
* 1) length <= maxpacket
* - DATA0
*
* 2) maxpacket < length <= (2 * maxpacket)
* - DATA1, DATA0
*
* 3) (2 * maxpacket) < length <= (3 * maxpacket)
* - DATA2, DATA1, DATA0
*/
if (speed == USB_SPEED_HIGH) {
struct usb_ep *ep = &dep->endpoint;
unsigned int mult = ep->mult - 1;
unsigned int maxp;
maxp = usb_endpoint_maxp(ep->desc) & 0x07ff;
if (length <= (2 * maxp))
mult--;
if (length <= maxp)
mult--;
trb->size |= DWC3_TRB_SIZE_PCM1(mult);
}
} else {
trb->ctrl = DWC3_TRBCTL_ISOCHRONOUS;
}
/* always enable Interrupt on Missed ISOC */
trb->ctrl |= DWC3_TRB_CTRL_ISP_IMI;
break;
case USB_ENDPOINT_XFER_BULK:
case USB_ENDPOINT_XFER_INT:
trb->ctrl = DWC3_TRBCTL_NORMAL;
break;
default:
/*
* This is only possible with faulty memory because we
* checked it already :)
*/
BUG();
}
/* always enable Continue on Short Packet */
trb->ctrl |= DWC3_TRB_CTRL_CSP;
if ((!req->request.no_interrupt && !chain) ||
(dwc3_calc_trbs_left(dep) == 0))
trb->ctrl |= DWC3_TRB_CTRL_IOC | DWC3_TRB_CTRL_ISP_IMI;
if (chain)
trb->ctrl |= DWC3_TRB_CTRL_CHN;
if (usb_endpoint_xfer_bulk(dep->endpoint.desc) && dep->stream_capable)
trb->ctrl |= DWC3_TRB_CTRL_SID_SOFN(req->request.stream_id);
trb->ctrl |= DWC3_TRB_CTRL_HWO;
trace_dwc3_prepare_trb(dep, trb);
}
/**
* dwc3_ep_prev_trb() - Returns the previous TRB in the ring
* @dep: The endpoint with the TRB ring
* @index: The index of the current TRB in the ring
*
* Returns the TRB prior to the one pointed to by the index. If the
* index is 0, we will wrap backwards, skip the link TRB, and return
* the one just before that.
*/
static struct dwc3_trb *dwc3_ep_prev_trb(struct dwc3_ep *dep, u8 index)
{
u8 tmp = index;
if (!tmp)
tmp = DWC3_TRB_NUM - 1;
return &dep->trb_pool[tmp - 1];
}
static u32 dwc3_calc_trbs_left(struct dwc3_ep *dep)
{
struct dwc3_trb *tmp;
u8 trbs_left;
/*
* If enqueue & dequeue are equal than it is either full or empty.
*
* One way to know for sure is if the TRB right before us has HWO bit
* set or not. If it has, then we're definitely full and can't fit any
* more transfers in our ring.
*/
if (dep->trb_enqueue == dep->trb_dequeue) {
tmp = dwc3_ep_prev_trb(dep, dep->trb_enqueue);
if (tmp->ctrl & DWC3_TRB_CTRL_HWO)
return 0;
return DWC3_TRB_NUM - 1;
}
trbs_left = dep->trb_dequeue - dep->trb_enqueue;
trbs_left &= (DWC3_TRB_NUM - 1);
if (dep->trb_dequeue < dep->trb_enqueue)
trbs_left--;
return trbs_left;
}
static void dwc3_prepare_one_trb_sg(struct dwc3_ep *dep,
struct dwc3_request *req)
{
struct scatterlist *sg = req->sg;
struct scatterlist *s;
unsigned int length;
dma_addr_t dma;
int i;
for_each_sg(sg, s, req->num_pending_sgs, i) {
unsigned chain = true;
length = sg_dma_len(s);
dma = sg_dma_address(s);
if (sg_is_last(s))
chain = false;
dwc3_prepare_one_trb(dep, req, dma, length,
chain, i);
if (!dwc3_calc_trbs_left(dep))
break;
}
}
static void dwc3_prepare_one_trb_linear(struct dwc3_ep *dep,
struct dwc3_request *req)
{
unsigned int length;
dma_addr_t dma;
dma = req->request.dma;
length = req->request.length;
dwc3_prepare_one_trb(dep, req, dma, length,
false, 0);
}
/*
* dwc3_prepare_trbs - setup TRBs from requests
* @dep: endpoint for which requests are being prepared
*
* The function goes through the requests list and sets up TRBs for the
* transfers. The function returns once there are no more TRBs available or
* it runs out of requests.
*/
static void dwc3_prepare_trbs(struct dwc3_ep *dep)
{
struct dwc3_request *req, *n;
BUILD_BUG_ON_NOT_POWER_OF_2(DWC3_TRB_NUM);
if (!dwc3_calc_trbs_left(dep))
return;
list_for_each_entry_safe(req, n, &dep->pending_list, list) {
if (req->num_pending_sgs > 0)
dwc3_prepare_one_trb_sg(dep, req);
else
dwc3_prepare_one_trb_linear(dep, req);
if (!dwc3_calc_trbs_left(dep))
return;
}
}
static int __dwc3_gadget_kick_transfer(struct dwc3_ep *dep, u16 cmd_param)
{
struct dwc3_gadget_ep_cmd_params params;
struct dwc3_request *req;
struct dwc3 *dwc = dep->dwc;
int starting;
int ret;
u32 cmd;
starting = !(dep->flags & DWC3_EP_BUSY);
dwc3_prepare_trbs(dep);
req = next_request(&dep->started_list);
if (!req) {
dep->flags |= DWC3_EP_PENDING_REQUEST;
return 0;
}
memset(&params, 0, sizeof(params));
if (starting) {
params.param0 = upper_32_bits(req->trb_dma);
params.param1 = lower_32_bits(req->trb_dma);
cmd = DWC3_DEPCMD_STARTTRANSFER |
DWC3_DEPCMD_PARAM(cmd_param);
} else {
cmd = DWC3_DEPCMD_UPDATETRANSFER |
DWC3_DEPCMD_PARAM(dep->resource_index);
}
ret = dwc3_send_gadget_ep_cmd(dep, cmd, &params);
if (ret < 0) {
/*
* FIXME we need to iterate over the list of requests
* here and stop, unmap, free and del each of the linked
* requests instead of what we do now.
*/
usb_gadget_unmap_request(&dwc->gadget, &req->request,
req->direction);
list_del(&req->list);
return ret;
}
dep->flags |= DWC3_EP_BUSY;
if (starting) {
dep->resource_index = dwc3_gadget_ep_get_transfer_index(dep);
WARN_ON_ONCE(!dep->resource_index);
}
return 0;
}
static void __dwc3_gadget_start_isoc(struct dwc3 *dwc,
struct dwc3_ep *dep, u32 cur_uf)
{
u32 uf;
if (list_empty(&dep->pending_list)) {
dwc3_trace(trace_dwc3_gadget,
"ISOC ep %s run out for requests",
dep->name);
dep->flags |= DWC3_EP_PENDING_REQUEST;
return;
}
/* 4 micro frames in the future */
uf = cur_uf + dep->interval * 4;
__dwc3_gadget_kick_transfer(dep, uf);
}
static void dwc3_gadget_start_isoc(struct dwc3 *dwc,
struct dwc3_ep *dep, const struct dwc3_event_depevt *event)
{
u32 cur_uf, mask;
mask = ~(dep->interval - 1);
cur_uf = event->parameters & mask;
__dwc3_gadget_start_isoc(dwc, dep, cur_uf);
}
static int __dwc3_gadget_ep_queue(struct dwc3_ep *dep, struct dwc3_request *req)
{
struct dwc3 *dwc = dep->dwc;
int ret;
if (!dep->endpoint.desc) {
dwc3_trace(trace_dwc3_gadget,
"trying to queue request %p to disabled %s",
&req->request, dep->endpoint.name);
return -ESHUTDOWN;
}
if (WARN(req->dep != dep, "request %pK belongs to '%s'\n",
&req->request, req->dep->name)) {
dwc3_trace(trace_dwc3_gadget, "request %pK belongs to '%s'",
&req->request, req->dep->name);
return -EINVAL;
}
pm_runtime_get(dwc->dev);
req->request.actual = 0;
req->request.status = -EINPROGRESS;
req->direction = dep->direction;
req->epnum = dep->number;
trace_dwc3_ep_queue(req);
ret = usb_gadget_map_request(&dwc->gadget, &req->request,
dep->direction);
if (ret)
return ret;
req->sg = req->request.sg;
req->num_pending_sgs = req->request.num_mapped_sgs;
list_add_tail(&req->list, &dep->pending_list);
/*
* NOTICE: Isochronous endpoints should NEVER be prestarted. We must
* wait for a XferNotReady event so we will know what's the current
* (micro-)frame number.
*
* Without this trick, we are very, very likely gonna get Bus Expiry
* errors which will force us issue EndTransfer command.
*/
if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
if ((dep->flags & DWC3_EP_PENDING_REQUEST) &&
list_empty(&dep->started_list)) {
dwc3_stop_active_transfer(dwc, dep->number, true);
dep->flags = DWC3_EP_ENABLED;
}
return 0;
}
if (!dwc3_calc_trbs_left(dep))
return 0;
ret = __dwc3_gadget_kick_transfer(dep, 0);
if (ret && ret != -EBUSY)
dwc3_trace(trace_dwc3_gadget,
"%s: failed to kick transfers",
dep->name);
if (ret == -EBUSY)
ret = 0;
return ret;
}
static void __dwc3_gadget_ep_zlp_complete(struct usb_ep *ep,
struct usb_request *request)
{
dwc3_gadget_ep_free_request(ep, request);
}
static int __dwc3_gadget_ep_queue_zlp(struct dwc3 *dwc, struct dwc3_ep *dep)
{
struct dwc3_request *req;
struct usb_request *request;
struct usb_ep *ep = &dep->endpoint;
dwc3_trace(trace_dwc3_gadget, "queueing ZLP");
request = dwc3_gadget_ep_alloc_request(ep, GFP_ATOMIC);
if (!request)
return -ENOMEM;
request->length = 0;
request->buf = dwc->zlp_buf;
request->complete = __dwc3_gadget_ep_zlp_complete;
req = to_dwc3_request(request);
return __dwc3_gadget_ep_queue(dep, req);
}
static int dwc3_gadget_ep_queue(struct usb_ep *ep, struct usb_request *request,
gfp_t gfp_flags)
{
struct dwc3_request *req = to_dwc3_request(request);
struct dwc3_ep *dep = to_dwc3_ep(ep);
struct dwc3 *dwc = dep->dwc;
unsigned long flags;
int ret;
spin_lock_irqsave(&dwc->lock, flags);
ret = __dwc3_gadget_ep_queue(dep, req);
/*
* Okay, here's the thing, if gadget driver has requested for a ZLP by
* setting request->zero, instead of doing magic, we will just queue an
* extra usb_request ourselves so that it gets handled the same way as
* any other request.
*/
if (ret == 0 && request->zero && request->length &&
(request->length % ep->maxpacket == 0))
ret = __dwc3_gadget_ep_queue_zlp(dwc, dep);
spin_unlock_irqrestore(&dwc->lock, flags);
return ret;
}
static int dwc3_gadget_ep_dequeue(struct usb_ep *ep,
struct usb_request *request)
{
struct dwc3_request *req = to_dwc3_request(request);
struct dwc3_request *r = NULL;
struct dwc3_ep *dep = to_dwc3_ep(ep);
struct dwc3 *dwc = dep->dwc;
unsigned long flags;
int ret = 0;
trace_dwc3_ep_dequeue(req);
spin_lock_irqsave(&dwc->lock, flags);
list_for_each_entry(r, &dep->pending_list, list) {
if (r == req)
break;
}
if (r != req) {
list_for_each_entry(r, &dep->started_list, list) {
if (r == req)
break;
}
if (r == req) {
/* wait until it is processed */
dwc3_stop_active_transfer(dwc, dep->number, true);
goto out1;
}
dev_err(dwc->dev, "request %pK was not queued to %s\n",
request, ep->name);
ret = -EINVAL;
goto out0;
}
out1:
/* giveback the request */
dwc3_gadget_giveback(dep, req, -ECONNRESET);
out0:
spin_unlock_irqrestore(&dwc->lock, flags);
return ret;
}
int __dwc3_gadget_ep_set_halt(struct dwc3_ep *dep, int value, int protocol)
{
struct dwc3_gadget_ep_cmd_params params;
struct dwc3 *dwc = dep->dwc;
int ret;
if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
dev_err(dwc->dev, "%s is of Isochronous type\n", dep->name);
return -EINVAL;
}
memset(&params, 0x00, sizeof(params));
if (value) {
struct dwc3_trb *trb;
unsigned transfer_in_flight;
unsigned started;
if (dep->number > 1)
trb = dwc3_ep_prev_trb(dep, dep->trb_enqueue);
else
trb = &dwc->ep0_trb[dep->trb_enqueue];
transfer_in_flight = trb->ctrl & DWC3_TRB_CTRL_HWO;
started = !list_empty(&dep->started_list);
if (!protocol && ((dep->direction && transfer_in_flight) ||
(!dep->direction && started))) {
dwc3_trace(trace_dwc3_gadget,
"%s: pending request, cannot halt",
dep->name);
return -EAGAIN;
}
ret = dwc3_send_gadget_ep_cmd(dep, DWC3_DEPCMD_SETSTALL,
&params);
if (ret)
dev_err(dwc->dev, "failed to set STALL on %s\n",
dep->name);
else
dep->flags |= DWC3_EP_STALL;
} else {
ret = dwc3_send_clear_stall_ep_cmd(dep);
if (ret)
dev_err(dwc->dev, "failed to clear STALL on %s\n",
dep->name);
else
dep->flags &= ~(DWC3_EP_STALL | DWC3_EP_WEDGE);
}
return ret;
}
static int dwc3_gadget_ep_set_halt(struct usb_ep *ep, int value)
{
struct dwc3_ep *dep = to_dwc3_ep(ep);
struct dwc3 *dwc = dep->dwc;
unsigned long flags;
int ret;
spin_lock_irqsave(&dwc->lock, flags);
ret = __dwc3_gadget_ep_set_halt(dep, value, false);
spin_unlock_irqrestore(&dwc->lock, flags);
return ret;
}
static int dwc3_gadget_ep_set_wedge(struct usb_ep *ep)
{
struct dwc3_ep *dep = to_dwc3_ep(ep);
struct dwc3 *dwc = dep->dwc;
unsigned long flags;
int ret;
spin_lock_irqsave(&dwc->lock, flags);
dep->flags |= DWC3_EP_WEDGE;
if (dep->number == 0 || dep->number == 1)
ret = __dwc3_gadget_ep0_set_halt(ep, 1);
else
ret = __dwc3_gadget_ep_set_halt(dep, 1, false);
spin_unlock_irqrestore(&dwc->lock, flags);
return ret;
}
/* -------------------------------------------------------------------------- */
static struct usb_endpoint_descriptor dwc3_gadget_ep0_desc = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bmAttributes = USB_ENDPOINT_XFER_CONTROL,
};
static const struct usb_ep_ops dwc3_gadget_ep0_ops = {
.enable = dwc3_gadget_ep0_enable,
.disable = dwc3_gadget_ep0_disable,
.alloc_request = dwc3_gadget_ep_alloc_request,
.free_request = dwc3_gadget_ep_free_request,
.queue = dwc3_gadget_ep0_queue,
.dequeue = dwc3_gadget_ep_dequeue,
.set_halt = dwc3_gadget_ep0_set_halt,
.set_wedge = dwc3_gadget_ep_set_wedge,
};
static const struct usb_ep_ops dwc3_gadget_ep_ops = {
.enable = dwc3_gadget_ep_enable,
.disable = dwc3_gadget_ep_disable,
.alloc_request = dwc3_gadget_ep_alloc_request,
.free_request = dwc3_gadget_ep_free_request,
.queue = dwc3_gadget_ep_queue,
.dequeue = dwc3_gadget_ep_dequeue,
.set_halt = dwc3_gadget_ep_set_halt,
.set_wedge = dwc3_gadget_ep_set_wedge,
};
/* -------------------------------------------------------------------------- */
static int dwc3_gadget_get_frame(struct usb_gadget *g)
{
struct dwc3 *dwc = gadget_to_dwc(g);
u32 reg;
reg = dwc3_readl(dwc->regs, DWC3_DSTS);
return DWC3_DSTS_SOFFN(reg);
}
static int __dwc3_gadget_wakeup(struct dwc3 *dwc)
{
int retries;
int ret;
u32 reg;
u8 link_state;
u8 speed;
/*
* According to the Databook Remote wakeup request should
* be issued only when the device is in early suspend state.
*
* We can check that via USB Link State bits in DSTS register.
*/
reg = dwc3_readl(dwc->regs, DWC3_DSTS);
speed = reg & DWC3_DSTS_CONNECTSPD;
if ((speed == DWC3_DSTS_SUPERSPEED) ||
(speed == DWC3_DSTS_SUPERSPEED_PLUS)) {
dwc3_trace(trace_dwc3_gadget, "no wakeup on SuperSpeed");
return 0;
}
link_state = DWC3_DSTS_USBLNKST(reg);
switch (link_state) {
case DWC3_LINK_STATE_RX_DET: /* in HS, means Early Suspend */
case DWC3_LINK_STATE_U3: /* in HS, means SUSPEND */
break;
default:
dwc3_trace(trace_dwc3_gadget,
"can't wakeup from '%s'",
dwc3_gadget_link_string(link_state));
return -EINVAL;
}
ret = dwc3_gadget_set_link_state(dwc, DWC3_LINK_STATE_RECOV);
if (ret < 0) {
dev_err(dwc->dev, "failed to put link in Recovery\n");
return ret;
}
/* Recent versions do this automatically */
if (dwc->revision < DWC3_REVISION_194A) {
/* write zeroes to Link Change Request */
reg = dwc3_readl(dwc->regs, DWC3_DCTL);
reg &= ~DWC3_DCTL_ULSTCHNGREQ_MASK;
dwc3_writel(dwc->regs, DWC3_DCTL, reg);
}
/* poll until Link State changes to ON */
retries = 20000;
while (retries--) {
reg = dwc3_readl(dwc->regs, DWC3_DSTS);
/* in HS, means ON */
if (DWC3_DSTS_USBLNKST(reg) == DWC3_LINK_STATE_U0)
break;
}
if (DWC3_DSTS_USBLNKST(reg) != DWC3_LINK_STATE_U0) {
dev_err(dwc->dev, "failed to send remote wakeup\n");
return -EINVAL;
}
return 0;
}
static int dwc3_gadget_wakeup(struct usb_gadget *g)
{
struct dwc3 *dwc = gadget_to_dwc(g);
unsigned long flags;
int ret;
spin_lock_irqsave(&dwc->lock, flags);
ret = __dwc3_gadget_wakeup(dwc);
spin_unlock_irqrestore(&dwc->lock, flags);
return ret;
}
static int dwc3_gadget_set_selfpowered(struct usb_gadget *g,
int is_selfpowered)
{
struct dwc3 *dwc = gadget_to_dwc(g);
unsigned long flags;
spin_lock_irqsave(&dwc->lock, flags);
g->is_selfpowered = !!is_selfpowered;
spin_unlock_irqrestore(&dwc->lock, flags);
return 0;
}
static int dwc3_gadget_run_stop(struct dwc3 *dwc, int is_on, int suspend)
{
u32 reg;
u32 timeout = 500;
if (pm_runtime_suspended(dwc->dev))
return 0;
reg = dwc3_readl(dwc->regs, DWC3_DCTL);
if (is_on) {
if (dwc->revision <= DWC3_REVISION_187A) {
reg &= ~DWC3_DCTL_TRGTULST_MASK;
reg |= DWC3_DCTL_TRGTULST_RX_DET;
}
if (dwc->revision >= DWC3_REVISION_194A)
reg &= ~DWC3_DCTL_KEEP_CONNECT;
reg |= DWC3_DCTL_RUN_STOP;
if (dwc->has_hibernation)
reg |= DWC3_DCTL_KEEP_CONNECT;
dwc->pullups_connected = true;
} else {
reg &= ~DWC3_DCTL_RUN_STOP;
if (dwc->has_hibernation && !suspend)
reg &= ~DWC3_DCTL_KEEP_CONNECT;
dwc->pullups_connected = false;
}
dwc3_writel(dwc->regs, DWC3_DCTL, reg);
do {
reg = dwc3_readl(dwc->regs, DWC3_DSTS);
reg &= DWC3_DSTS_DEVCTRLHLT;
} while (--timeout && !(!is_on ^ !reg));
if (!timeout)
return -ETIMEDOUT;
dwc3_trace(trace_dwc3_gadget, "gadget %s data soft-%s",
dwc->gadget_driver
? dwc->gadget_driver->function : "no-function",
is_on ? "connect" : "disconnect");
return 0;
}
static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
{
struct dwc3 *dwc = gadget_to_dwc(g);
unsigned long flags;
int ret;
is_on = !!is_on;
spin_lock_irqsave(&dwc->lock, flags);
ret = dwc3_gadget_run_stop(dwc, is_on, false);
spin_unlock_irqrestore(&dwc->lock, flags);
return ret;
}
static void dwc3_gadget_enable_irq(struct dwc3 *dwc)
{
u32 reg;
/* Enable all but Start and End of Frame IRQs */
reg = (DWC3_DEVTEN_VNDRDEVTSTRCVEDEN |
DWC3_DEVTEN_EVNTOVERFLOWEN |
DWC3_DEVTEN_CMDCMPLTEN |
DWC3_DEVTEN_ERRTICERREN |
DWC3_DEVTEN_WKUPEVTEN |
DWC3_DEVTEN_ULSTCNGEN |
DWC3_DEVTEN_CONNECTDONEEN |
DWC3_DEVTEN_USBRSTEN |
DWC3_DEVTEN_DISCONNEVTEN);
dwc3_writel(dwc->regs, DWC3_DEVTEN, reg);
}
static void dwc3_gadget_disable_irq(struct dwc3 *dwc)
{
/* mask all interrupts */
dwc3_writel(dwc->regs, DWC3_DEVTEN, 0x00);
}
static irqreturn_t dwc3_interrupt(int irq, void *_dwc);
static irqreturn_t dwc3_thread_interrupt(int irq, void *_dwc);
/**
* dwc3_gadget_setup_nump - Calculate and initialize NUMP field of DCFG
* dwc: pointer to our context structure
*
* The following looks like complex but it's actually very simple. In order to
* calculate the number of packets we can burst at once on OUT transfers, we're
* gonna use RxFIFO size.
*
* To calculate RxFIFO size we need two numbers:
* MDWIDTH = size, in bits, of the internal memory bus
* RAM2_DEPTH = depth, in MDWIDTH, of internal RAM2 (where RxFIFO sits)
*
* Given these two numbers, the formula is simple:
*
* RxFIFO Size = (RAM2_DEPTH * MDWIDTH / 8) - 24 - 16;
*
* 24 bytes is for 3x SETUP packets
* 16 bytes is a clock domain crossing tolerance
*
* Given RxFIFO Size, NUMP = RxFIFOSize / 1024;
*/
static void dwc3_gadget_setup_nump(struct dwc3 *dwc)
{
u32 ram2_depth;
u32 mdwidth;
u32 nump;
u32 reg;
ram2_depth = DWC3_GHWPARAMS7_RAM2_DEPTH(dwc->hwparams.hwparams7);
mdwidth = DWC3_GHWPARAMS0_MDWIDTH(dwc->hwparams.hwparams0);
nump = ((ram2_depth * mdwidth / 8) - 24 - 16) / 1024;
nump = min_t(u32, nump, 16);
/* update NumP */
reg = dwc3_readl(dwc->regs, DWC3_DCFG);
reg &= ~DWC3_DCFG_NUMP_MASK;
reg |= nump << DWC3_DCFG_NUMP_SHIFT;
dwc3_writel(dwc->regs, DWC3_DCFG, reg);
}
static int __dwc3_gadget_start(struct dwc3 *dwc)
{
struct dwc3_ep *dep;
int ret = 0;
u32 reg;
reg = dwc3_readl(dwc->regs, DWC3_DCFG);
reg &= ~(DWC3_DCFG_SPEED_MASK);
/**
* WORKAROUND: DWC3 revision < 2.20a have an issue
* which would cause metastability state on Run/Stop
* bit if we try to force the IP to USB2-only mode.
*
* Because of that, we cannot configure the IP to any
* speed other than the SuperSpeed
*
* Refers to:
*
* STAR#9000525659: Clock Domain Crossing on DCTL in
* USB 2.0 Mode
*/
if (dwc->revision < DWC3_REVISION_220A) {
reg |= DWC3_DCFG_SUPERSPEED;
} else {
switch (dwc->maximum_speed) {
case USB_SPEED_LOW:
reg |= DWC3_DCFG_LOWSPEED;
break;
case USB_SPEED_FULL:
reg |= DWC3_DCFG_FULLSPEED;
break;
case USB_SPEED_HIGH:
reg |= DWC3_DCFG_HIGHSPEED;
break;
case USB_SPEED_SUPER_PLUS:
reg |= DWC3_DCFG_SUPERSPEED_PLUS;
break;
default:
dev_err(dwc->dev, "invalid dwc->maximum_speed (%d)\n",
dwc->maximum_speed);
/* fall through */
case USB_SPEED_SUPER:
reg |= DWC3_DCFG_SUPERSPEED;
break;
}
}
dwc3_writel(dwc->regs, DWC3_DCFG, reg);
/*
* We are telling dwc3 that we want to use DCFG.NUMP as ACK TP's NUMP
* field instead of letting dwc3 itself calculate that automatically.
*
* This way, we maximize the chances that we'll be able to get several
* bursts of data without going through any sort of endpoint throttling.
*/
reg = dwc3_readl(dwc->regs, DWC3_GRXTHRCFG);
reg &= ~DWC3_GRXTHRCFG_PKTCNTSEL;
dwc3_writel(dwc->regs, DWC3_GRXTHRCFG, reg);
dwc3_gadget_setup_nump(dwc);
/* Start with SuperSpeed Default */
dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(512);
dep = dwc->eps[0];
ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, false,
false);
if (ret) {
dev_err(dwc->dev, "failed to enable %s\n", dep->name);
goto err0;
}
dep = dwc->eps[1];
ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, false,
false);
if (ret) {
dev_err(dwc->dev, "failed to enable %s\n", dep->name);
goto err1;
}
/* begin to receive SETUP packets */
dwc->ep0state = EP0_SETUP_PHASE;
dwc->link_state = DWC3_LINK_STATE_SS_DIS;
dwc3_ep0_out_start(dwc);
dwc3_gadget_enable_irq(dwc);
return 0;
err1:
__dwc3_gadget_ep_disable(dwc->eps[0]);
err0:
return ret;
}
static int dwc3_gadget_start(struct usb_gadget *g,
struct usb_gadget_driver *driver)
{
struct dwc3 *dwc = gadget_to_dwc(g);
unsigned long flags;
int ret = 0;
int irq;
irq = dwc->irq_gadget;
ret = request_threaded_irq(irq, dwc3_interrupt, dwc3_thread_interrupt,
IRQF_SHARED, "dwc3", dwc->ev_buf);
if (ret) {
dev_err(dwc->dev, "failed to request irq #%d --> %d\n",
irq, ret);
goto err0;
}
spin_lock_irqsave(&dwc->lock, flags);
if (dwc->gadget_driver) {
dev_err(dwc->dev, "%s is already bound to %s\n",
dwc->gadget.name,
dwc->gadget_driver->driver.name);
ret = -EBUSY;
goto err1;
}
dwc->gadget_driver = driver;
if (pm_runtime_active(dwc->dev))
__dwc3_gadget_start(dwc);
spin_unlock_irqrestore(&dwc->lock, flags);
return 0;
err1:
spin_unlock_irqrestore(&dwc->lock, flags);
free_irq(irq, dwc);
err0:
return ret;
}
static void __dwc3_gadget_stop(struct dwc3 *dwc)
{
if (pm_runtime_suspended(dwc->dev))
return;
dwc3_gadget_disable_irq(dwc);
__dwc3_gadget_ep_disable(dwc->eps[0]);
__dwc3_gadget_ep_disable(dwc->eps[1]);
}
static int dwc3_gadget_stop(struct usb_gadget *g)
{
struct dwc3 *dwc = gadget_to_dwc(g);
unsigned long flags;
spin_lock_irqsave(&dwc->lock, flags);
__dwc3_gadget_stop(dwc);
dwc->gadget_driver = NULL;
spin_unlock_irqrestore(&dwc->lock, flags);
free_irq(dwc->irq_gadget, dwc->ev_buf);
return 0;
}
static const struct usb_gadget_ops dwc3_gadget_ops = {
.get_frame = dwc3_gadget_get_frame,
.wakeup = dwc3_gadget_wakeup,
.set_selfpowered = dwc3_gadget_set_selfpowered,
.pullup = dwc3_gadget_pullup,
.udc_start = dwc3_gadget_start,
.udc_stop = dwc3_gadget_stop,
};
/* -------------------------------------------------------------------------- */
static int dwc3_gadget_init_hw_endpoints(struct dwc3 *dwc,
u8 num, u32 direction)
{
struct dwc3_ep *dep;
u8 i;
for (i = 0; i < num; i++) {
u8 epnum = (i << 1) | (direction ? 1 : 0);
dep = kzalloc(sizeof(*dep), GFP_KERNEL);
if (!dep)
return -ENOMEM;
dep->dwc = dwc;
dep->number = epnum;
dep->direction = !!direction;
dep->regs = dwc->regs + DWC3_DEP_BASE(epnum);
dwc->eps[epnum] = dep;
snprintf(dep->name, sizeof(dep->name), "ep%d%s", epnum >> 1,
(epnum & 1) ? "in" : "out");
dep->endpoint.name = dep->name;
spin_lock_init(&dep->lock);
dwc3_trace(trace_dwc3_gadget, "initializing %s", dep->name);
if (epnum == 0 || epnum == 1) {
usb_ep_set_maxpacket_limit(&dep->endpoint, 512);
dep->endpoint.maxburst = 1;
dep->endpoint.ops = &dwc3_gadget_ep0_ops;
if (!epnum)
dwc->gadget.ep0 = &dep->endpoint;
} else {
int ret;
usb_ep_set_maxpacket_limit(&dep->endpoint, 1024);
dep->endpoint.max_streams = 15;
dep->endpoint.ops = &dwc3_gadget_ep_ops;
list_add_tail(&dep->endpoint.ep_list,
&dwc->gadget.ep_list);
ret = dwc3_alloc_trb_pool(dep);
if (ret)
return ret;
}
if (epnum == 0 || epnum == 1) {
dep->endpoint.caps.type_control = true;
} else {
dep->endpoint.caps.type_iso = true;
dep->endpoint.caps.type_bulk = true;
dep->endpoint.caps.type_int = true;
}
dep->endpoint.caps.dir_in = !!direction;
dep->endpoint.caps.dir_out = !direction;
INIT_LIST_HEAD(&dep->pending_list);
INIT_LIST_HEAD(&dep->started_list);
}
return 0;
}
static int dwc3_gadget_init_endpoints(struct dwc3 *dwc)
{
int ret;
INIT_LIST_HEAD(&dwc->gadget.ep_list);
ret = dwc3_gadget_init_hw_endpoints(dwc, dwc->num_out_eps, 0);
if (ret < 0) {
dwc3_trace(trace_dwc3_gadget,
"failed to allocate OUT endpoints");
return ret;
}
ret = dwc3_gadget_init_hw_endpoints(dwc, dwc->num_in_eps, 1);
if (ret < 0) {
dwc3_trace(trace_dwc3_gadget,
"failed to allocate IN endpoints");
return ret;
}
return 0;
}
static void dwc3_gadget_free_endpoints(struct dwc3 *dwc)
{
struct dwc3_ep *dep;
u8 epnum;
for (epnum = 0; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
dep = dwc->eps[epnum];
if (!dep)
continue;
/*
* Physical endpoints 0 and 1 are special; they form the
* bi-directional USB endpoint 0.
*
* For those two physical endpoints, we don't allocate a TRB
* pool nor do we add them the endpoints list. Due to that, we
* shouldn't do these two operations otherwise we would end up
* with all sorts of bugs when removing dwc3.ko.
*/
if (epnum != 0 && epnum != 1) {
dwc3_free_trb_pool(dep);
list_del(&dep->endpoint.ep_list);
}
kfree(dep);
}
}
/* -------------------------------------------------------------------------- */
static int __dwc3_cleanup_done_trbs(struct dwc3 *dwc, struct dwc3_ep *dep,
struct dwc3_request *req, struct dwc3_trb *trb,
const struct dwc3_event_depevt *event, int status,
int chain)
{
unsigned int count;
unsigned int s_pkt = 0;
unsigned int trb_status;
dwc3_ep_inc_deq(dep);
if (req->trb == trb)
dep->queued_requests--;
trace_dwc3_complete_trb(dep, trb);
/*
* If we're in the middle of series of chained TRBs and we
* receive a short transfer along the way, DWC3 will skip
* through all TRBs including the last TRB in the chain (the
* where CHN bit is zero. DWC3 will also avoid clearing HWO
* bit and SW has to do it manually.
*
* We're going to do that here to avoid problems of HW trying
* to use bogus TRBs for transfers.
*/
if (chain && (trb->ctrl & DWC3_TRB_CTRL_HWO))
trb->ctrl &= ~DWC3_TRB_CTRL_HWO;
if ((trb->ctrl & DWC3_TRB_CTRL_HWO) && status != -ESHUTDOWN)
return 1;
count = trb->size & DWC3_TRB_SIZE_MASK;
req->request.actual += count;
if (dep->direction) {
if (count) {
trb_status = DWC3_TRB_SIZE_TRBSTS(trb->size);
if (trb_status == DWC3_TRBSTS_MISSED_ISOC) {
dwc3_trace(trace_dwc3_gadget,
"%s: incomplete IN transfer",
dep->name);
/*
* If missed isoc occurred and there is
* no request queued then issue END
* TRANSFER, so that core generates
* next xfernotready and we will issue
* a fresh START TRANSFER.
* If there are still queued request
* then wait, do not issue either END
* or UPDATE TRANSFER, just attach next
* request in pending_list during
* giveback.If any future queued request
* is successfully transferred then we
* will issue UPDATE TRANSFER for all
* request in the pending_list.
*/
dep->flags |= DWC3_EP_MISSED_ISOC;
} else {
dev_err(dwc->dev, "incomplete IN transfer %s\n",
dep->name);
status = -ECONNRESET;
}
} else {
dep->flags &= ~DWC3_EP_MISSED_ISOC;
}
} else {
if (count && (event->status & DEPEVT_STATUS_SHORT))
s_pkt = 1;
}
if (s_pkt && !chain)
return 1;
if ((event->status & DEPEVT_STATUS_IOC) &&
(trb->ctrl & DWC3_TRB_CTRL_IOC))
return 1;
return 0;
}
static int dwc3_cleanup_done_reqs(struct dwc3 *dwc, struct dwc3_ep *dep,
const struct dwc3_event_depevt *event, int status)
{
struct dwc3_request *req, *n;
struct dwc3_trb *trb;
bool ioc = false;
int ret;
list_for_each_entry_safe(req, n, &dep->started_list, list) {
unsigned length;
unsigned actual;
int chain;
length = req->request.length;
chain = req->num_pending_sgs > 0;
if (chain) {
struct scatterlist *sg = req->sg;
struct scatterlist *s;
unsigned int pending = req->num_pending_sgs;
unsigned int i;
for_each_sg(sg, s, pending, i) {
trb = &dep->trb_pool[dep->trb_dequeue];
req->sg = sg_next(s);
req->num_pending_sgs--;
ret = __dwc3_cleanup_done_trbs(dwc, dep, req, trb,
event, status, chain);
if (ret)
break;
}
} else {
trb = &dep->trb_pool[dep->trb_dequeue];
ret = __dwc3_cleanup_done_trbs(dwc, dep, req, trb,
event, status, chain);
}
/*
* We assume here we will always receive the entire data block
* which we should receive. Meaning, if we program RX to
* receive 4K but we receive only 2K, we assume that's all we
* should receive and we simply bounce the request back to the
* gadget driver for further processing.
*/
actual = length - req->request.actual;
req->request.actual = actual;
if (ret && chain && (actual < length) && req->num_pending_sgs)
return __dwc3_gadget_kick_transfer(dep, 0);
dwc3_gadget_giveback(dep, req, status);
if (ret) {
if ((event->status & DEPEVT_STATUS_IOC) &&
(trb->ctrl & DWC3_TRB_CTRL_IOC))
ioc = true;
break;
}
}
/*
* Our endpoint might get disabled by another thread during
* dwc3_gadget_giveback(). If that happens, we're just gonna return 1
* early on so DWC3_EP_BUSY flag gets cleared
*/
if (!dep->endpoint.desc)
return 1;
if (usb_endpoint_xfer_isoc(dep->endpoint.desc) &&
list_empty(&dep->started_list)) {
if (list_empty(&dep->pending_list)) {
/*
* If there is no entry in request list then do
* not issue END TRANSFER now. Just set PENDING
* flag, so that END TRANSFER is issued when an
* entry is added into request list.
*/
dep->flags = DWC3_EP_PENDING_REQUEST;
} else {
dwc3_stop_active_transfer(dwc, dep->number, true);
dep->flags = DWC3_EP_ENABLED;
}
return 1;
}
if (usb_endpoint_xfer_isoc(dep->endpoint.desc) && ioc)
return 0;
return 1;
}
static void dwc3_endpoint_transfer_complete(struct dwc3 *dwc,
struct dwc3_ep *dep, const struct dwc3_event_depevt *event)
{
unsigned status = 0;
int clean_busy;
u32 is_xfer_complete;
is_xfer_complete = (event->endpoint_event == DWC3_DEPEVT_XFERCOMPLETE);
if (event->status & DEPEVT_STATUS_BUSERR)
status = -ECONNRESET;
clean_busy = dwc3_cleanup_done_reqs(dwc, dep, event, status);
if (clean_busy && (!dep->endpoint.desc || is_xfer_complete ||
usb_endpoint_xfer_isoc(dep->endpoint.desc)))
dep->flags &= ~DWC3_EP_BUSY;
/*
* WORKAROUND: This is the 2nd half of U1/U2 -> U0 workaround.
* See dwc3_gadget_linksts_change_interrupt() for 1st half.
*/
if (dwc->revision < DWC3_REVISION_183A) {
u32 reg;
int i;
for (i = 0; i < DWC3_ENDPOINTS_NUM; i++) {
dep = dwc->eps[i];
if (!(dep->flags & DWC3_EP_ENABLED))
continue;
if (!list_empty(&dep->started_list))
return;
}
reg = dwc3_readl(dwc->regs, DWC3_DCTL);
reg |= dwc->u1u2;
dwc3_writel(dwc->regs, DWC3_DCTL, reg);
dwc->u1u2 = 0;
}
/*
* Our endpoint might get disabled by another thread during
* dwc3_gadget_giveback(). If that happens, we're just gonna return 1
* early on so DWC3_EP_BUSY flag gets cleared
*/
if (!dep->endpoint.desc)
return;
if (!usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
int ret;
ret = __dwc3_gadget_kick_transfer(dep, 0);
if (!ret || ret == -EBUSY)
return;
}
}
static void dwc3_endpoint_interrupt(struct dwc3 *dwc,
const struct dwc3_event_depevt *event)
{
struct dwc3_ep *dep;
u8 epnum = event->endpoint_number;
dep = dwc->eps[epnum];
if (!(dep->flags & DWC3_EP_ENABLED))
return;
if (epnum == 0 || epnum == 1) {
dwc3_ep0_interrupt(dwc, event);
return;
}
switch (event->endpoint_event) {
case DWC3_DEPEVT_XFERCOMPLETE:
dep->resource_index = 0;
if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
dwc3_trace(trace_dwc3_gadget,
"%s is an Isochronous endpoint",
dep->name);
return;
}
dwc3_endpoint_transfer_complete(dwc, dep, event);
break;
case DWC3_DEPEVT_XFERINPROGRESS:
dwc3_endpoint_transfer_complete(dwc, dep, event);
break;
case DWC3_DEPEVT_XFERNOTREADY:
if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
dwc3_gadget_start_isoc(dwc, dep, event);
} else {
int active;
int ret;
active = event->status & DEPEVT_STATUS_TRANSFER_ACTIVE;
dwc3_trace(trace_dwc3_gadget, "%s: reason %s",
dep->name, active ? "Transfer Active"
: "Transfer Not Active");
ret = __dwc3_gadget_kick_transfer(dep, 0);
if (!ret || ret == -EBUSY)
return;
dwc3_trace(trace_dwc3_gadget,
"%s: failed to kick transfers",
dep->name);
}
break;
case DWC3_DEPEVT_STREAMEVT:
if (!usb_endpoint_xfer_bulk(dep->endpoint.desc)) {
dev_err(dwc->dev, "Stream event for non-Bulk %s\n",
dep->name);
return;
}
switch (event->status) {
case DEPEVT_STREAMEVT_FOUND:
dwc3_trace(trace_dwc3_gadget,
"Stream %d found and started",
event->parameters);
break;
case DEPEVT_STREAMEVT_NOTFOUND:
/* FALLTHROUGH */
default:
dwc3_trace(trace_dwc3_gadget,
"unable to find suitable stream");
}
break;
case DWC3_DEPEVT_RXTXFIFOEVT:
dwc3_trace(trace_dwc3_gadget, "%s FIFO Overrun", dep->name);
break;
case DWC3_DEPEVT_EPCMDCMPLT:
dwc3_trace(trace_dwc3_gadget, "Endpoint Command Complete");
break;
}
}
static void dwc3_disconnect_gadget(struct dwc3 *dwc)
{
if (dwc->gadget_driver && dwc->gadget_driver->disconnect) {
spin_unlock(&dwc->lock);
dwc->gadget_driver->disconnect(&dwc->gadget);
spin_lock(&dwc->lock);
}
}
static void dwc3_suspend_gadget(struct dwc3 *dwc)
{
if (dwc->gadget_driver && dwc->gadget_driver->suspend) {
spin_unlock(&dwc->lock);
dwc->gadget_driver->suspend(&dwc->gadget);
spin_lock(&dwc->lock);
}
}
static void dwc3_resume_gadget(struct dwc3 *dwc)
{
if (dwc->gadget_driver && dwc->gadget_driver->resume) {
spin_unlock(&dwc->lock);
dwc->gadget_driver->resume(&dwc->gadget);
spin_lock(&dwc->lock);
}
}
static void dwc3_reset_gadget(struct dwc3 *dwc)
{
if (!dwc->gadget_driver)
return;
if (dwc->gadget.speed != USB_SPEED_UNKNOWN) {
spin_unlock(&dwc->lock);
usb_gadget_udc_reset(&dwc->gadget, dwc->gadget_driver);
spin_lock(&dwc->lock);
}
}
static void dwc3_stop_active_transfer(struct dwc3 *dwc, u32 epnum, bool force)
{
struct dwc3_ep *dep;
struct dwc3_gadget_ep_cmd_params params;
u32 cmd;
int ret;
dep = dwc->eps[epnum];
if (!dep->resource_index)
return;
/*
* NOTICE: We are violating what the Databook says about the
* EndTransfer command. Ideally we would _always_ wait for the
* EndTransfer Command Completion IRQ, but that's causing too
* much trouble synchronizing between us and gadget driver.
*
* We have discussed this with the IP Provider and it was
* suggested to giveback all requests here, but give HW some
* extra time to synchronize with the interconnect. We're using
* an arbitrary 100us delay for that.
*
* Note also that a similar handling was tested by Synopsys
* (thanks a lot Paul) and nothing bad has come out of it.
* In short, what we're doing is:
*
* - Issue EndTransfer WITH CMDIOC bit set
* - Wait 100us
*
* As of IP version 3.10a of the DWC_usb3 IP, the controller
* supports a mode to work around the above limitation. The
* software can poll the CMDACT bit in the DEPCMD register
* after issuing a EndTransfer command. This mode is enabled
* by writing GUCTL2[14]. This polling is already done in the
* dwc3_send_gadget_ep_cmd() function so if the mode is
* enabled, the EndTransfer command will have completed upon
* returning from this function and we don't need to delay for
* 100us.
*
* This mode is NOT available on the DWC_usb31 IP.
*/
cmd = DWC3_DEPCMD_ENDTRANSFER;
cmd |= force ? DWC3_DEPCMD_HIPRI_FORCERM : 0;
cmd |= DWC3_DEPCMD_CMDIOC;
cmd |= DWC3_DEPCMD_PARAM(dep->resource_index);
memset(&params, 0, sizeof(params));
ret = dwc3_send_gadget_ep_cmd(dep, cmd, &params);
WARN_ON_ONCE(ret);
dep->resource_index = 0;
dep->flags &= ~DWC3_EP_BUSY;
if (dwc3_is_usb31(dwc) || dwc->revision < DWC3_REVISION_310A)
udelay(100);
}
static void dwc3_stop_active_transfers(struct dwc3 *dwc)
{
u32 epnum;
for (epnum = 2; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
struct dwc3_ep *dep;
dep = dwc->eps[epnum];
if (!dep)
continue;
if (!(dep->flags & DWC3_EP_ENABLED))
continue;
dwc3_remove_requests(dwc, dep);
}
}
static void dwc3_clear_stall_all_ep(struct dwc3 *dwc)
{
u32 epnum;
for (epnum = 1; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
struct dwc3_ep *dep;
int ret;
dep = dwc->eps[epnum];
if (!dep)
continue;
if (!(dep->flags & DWC3_EP_STALL))
continue;
dep->flags &= ~DWC3_EP_STALL;
ret = dwc3_send_clear_stall_ep_cmd(dep);
WARN_ON_ONCE(ret);
}
}
static void dwc3_gadget_disconnect_interrupt(struct dwc3 *dwc)
{
int reg;
reg = dwc3_readl(dwc->regs, DWC3_DCTL);
reg &= ~DWC3_DCTL_INITU1ENA;
dwc3_writel(dwc->regs, DWC3_DCTL, reg);
reg &= ~DWC3_DCTL_INITU2ENA;
dwc3_writel(dwc->regs, DWC3_DCTL, reg);
dwc3_disconnect_gadget(dwc);
dwc->gadget.speed = USB_SPEED_UNKNOWN;
dwc->setup_packet_pending = false;
usb_gadget_set_state(&dwc->gadget, USB_STATE_NOTATTACHED);
dwc->connected = false;
}
static void dwc3_gadget_reset_interrupt(struct dwc3 *dwc)
{
u32 reg;
dwc->connected = true;
/*
* WORKAROUND: DWC3 revisions <1.88a have an issue which
* would cause a missing Disconnect Event if there's a
* pending Setup Packet in the FIFO.
*
* There's no suggested workaround on the official Bug
* report, which states that "unless the driver/application
* is doing any special handling of a disconnect event,
* there is no functional issue".
*
* Unfortunately, it turns out that we _do_ some special
* handling of a disconnect event, namely complete all
* pending transfers, notify gadget driver of the
* disconnection, and so on.
*
* Our suggested workaround is to follow the Disconnect
* Event steps here, instead, based on a setup_packet_pending
* flag. Such flag gets set whenever we have a SETUP_PENDING
* status for EP0 TRBs and gets cleared on XferComplete for the
* same endpoint.
*
* Refers to:
*
* STAR#9000466709: RTL: Device : Disconnect event not
* generated if setup packet pending in FIFO
*/
if (dwc->revision < DWC3_REVISION_188A) {
if (dwc->setup_packet_pending)
dwc3_gadget_disconnect_interrupt(dwc);
}
dwc3_reset_gadget(dwc);
reg = dwc3_readl(dwc->regs, DWC3_DCTL);
reg &= ~DWC3_DCTL_TSTCTRL_MASK;
dwc3_writel(dwc->regs, DWC3_DCTL, reg);
dwc->test_mode = false;
dwc3_stop_active_transfers(dwc);
dwc3_clear_stall_all_ep(dwc);
/* Reset device address to zero */
reg = dwc3_readl(dwc->regs, DWC3_DCFG);
reg &= ~(DWC3_DCFG_DEVADDR_MASK);
dwc3_writel(dwc->regs, DWC3_DCFG, reg);
}
static void dwc3_update_ram_clk_sel(struct dwc3 *dwc, u32 speed)
{
u32 reg;
u32 usb30_clock = DWC3_GCTL_CLK_BUS;
/*
* We change the clock only at SS but I dunno why I would want to do
* this. Maybe it becomes part of the power saving plan.
*/
if ((speed != DWC3_DSTS_SUPERSPEED) &&
(speed != DWC3_DSTS_SUPERSPEED_PLUS))
return;
/*
* RAMClkSel is reset to 0 after USB reset, so it must be reprogrammed
* each time on Connect Done.
*/
if (!usb30_clock)
return;
reg = dwc3_readl(dwc->regs, DWC3_GCTL);
reg |= DWC3_GCTL_RAMCLKSEL(usb30_clock);
dwc3_writel(dwc->regs, DWC3_GCTL, reg);
}
static void dwc3_gadget_conndone_interrupt(struct dwc3 *dwc)
{
struct dwc3_ep *dep;
int ret;
u32 reg;
u8 speed;
reg = dwc3_readl(dwc->regs, DWC3_DSTS);
speed = reg & DWC3_DSTS_CONNECTSPD;
dwc->speed = speed;
dwc3_update_ram_clk_sel(dwc, speed);
switch (speed) {
case DWC3_DSTS_SUPERSPEED_PLUS:
dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(512);
dwc->gadget.ep0->maxpacket = 512;
dwc->gadget.speed = USB_SPEED_SUPER_PLUS;
break;
case DWC3_DSTS_SUPERSPEED:
/*
* WORKAROUND: DWC3 revisions <1.90a have an issue which
* would cause a missing USB3 Reset event.
*
* In such situations, we should force a USB3 Reset
* event by calling our dwc3_gadget_reset_interrupt()
* routine.
*
* Refers to:
*
* STAR#9000483510: RTL: SS : USB3 reset event may
* not be generated always when the link enters poll
*/
if (dwc->revision < DWC3_REVISION_190A)
dwc3_gadget_reset_interrupt(dwc);
dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(512);
dwc->gadget.ep0->maxpacket = 512;
dwc->gadget.speed = USB_SPEED_SUPER;
break;
case DWC3_DSTS_HIGHSPEED:
dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(64);
dwc->gadget.ep0->maxpacket = 64;
dwc->gadget.speed = USB_SPEED_HIGH;
break;
case DWC3_DSTS_FULLSPEED:
dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(64);
dwc->gadget.ep0->maxpacket = 64;
dwc->gadget.speed = USB_SPEED_FULL;
break;
case DWC3_DSTS_LOWSPEED:
dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(8);
dwc->gadget.ep0->maxpacket = 8;
dwc->gadget.speed = USB_SPEED_LOW;
break;
}
dwc->eps[1]->endpoint.maxpacket = dwc->gadget.ep0->maxpacket;
/* Enable USB2 LPM Capability */
if ((dwc->revision > DWC3_REVISION_194A) &&
(speed != DWC3_DSTS_SUPERSPEED) &&
(speed != DWC3_DSTS_SUPERSPEED_PLUS)) {
reg = dwc3_readl(dwc->regs, DWC3_DCFG);
reg |= DWC3_DCFG_LPM_CAP;
dwc3_writel(dwc->regs, DWC3_DCFG, reg);
reg = dwc3_readl(dwc->regs, DWC3_DCTL);
reg &= ~(DWC3_DCTL_HIRD_THRES_MASK | DWC3_DCTL_L1_HIBER_EN);
reg |= DWC3_DCTL_HIRD_THRES(dwc->hird_threshold);
/*
* When dwc3 revisions >= 2.40a, LPM Erratum is enabled and
* DCFG.LPMCap is set, core responses with an ACK and the
* BESL value in the LPM token is less than or equal to LPM
* NYET threshold.
*/
WARN_ONCE(dwc->revision < DWC3_REVISION_240A
&& dwc->has_lpm_erratum,
"LPM Erratum not available on dwc3 revisisions < 2.40a\n");
if (dwc->has_lpm_erratum && dwc->revision >= DWC3_REVISION_240A)
reg |= DWC3_DCTL_LPM_ERRATA(dwc->lpm_nyet_threshold);
dwc3_writel(dwc->regs, DWC3_DCTL, reg);
} else {
reg = dwc3_readl(dwc->regs, DWC3_DCTL);
reg &= ~DWC3_DCTL_HIRD_THRES_MASK;
dwc3_writel(dwc->regs, DWC3_DCTL, reg);
}
dep = dwc->eps[0];
ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, true,
false);
if (ret) {
dev_err(dwc->dev, "failed to enable %s\n", dep->name);
return;
}
dep = dwc->eps[1];
ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, true,
false);
if (ret) {
dev_err(dwc->dev, "failed to enable %s\n", dep->name);
return;
}
/*
* Configure PHY via GUSB3PIPECTLn if required.
*
* Update GTXFIFOSIZn
*
* In both cases reset values should be sufficient.
*/
}
static void dwc3_gadget_wakeup_interrupt(struct dwc3 *dwc)
{
/*
* TODO take core out of low power mode when that's
* implemented.
*/
if (dwc->gadget_driver && dwc->gadget_driver->resume) {
spin_unlock(&dwc->lock);
dwc->gadget_driver->resume(&dwc->gadget);
spin_lock(&dwc->lock);
}
}
static void dwc3_gadget_linksts_change_interrupt(struct dwc3 *dwc,
unsigned int evtinfo)
{
enum dwc3_link_state next = evtinfo & DWC3_LINK_STATE_MASK;
unsigned int pwropt;
/*
* WORKAROUND: DWC3 < 2.50a have an issue when configured without
* Hibernation mode enabled which would show up when device detects
* host-initiated U3 exit.
*
* In that case, device will generate a Link State Change Interrupt
* from U3 to RESUME which is only necessary if Hibernation is
* configured in.
*
* There are no functional changes due to such spurious event and we
* just need to ignore it.
*
* Refers to:
*
* STAR#9000570034 RTL: SS Resume event generated in non-Hibernation
* operational mode
*/
pwropt = DWC3_GHWPARAMS1_EN_PWROPT(dwc->hwparams.hwparams1);
if ((dwc->revision < DWC3_REVISION_250A) &&
(pwropt != DWC3_GHWPARAMS1_EN_PWROPT_HIB)) {
if ((dwc->link_state == DWC3_LINK_STATE_U3) &&
(next == DWC3_LINK_STATE_RESUME)) {
dwc3_trace(trace_dwc3_gadget,
"ignoring transition U3 -> Resume");
return;
}
}
/*
* WORKAROUND: DWC3 Revisions <1.83a have an issue which, depending
* on the link partner, the USB session might do multiple entry/exit
* of low power states before a transfer takes place.
*
* Due to this problem, we might experience lower throughput. The
* suggested workaround is to disable DCTL[12:9] bits if we're
* transitioning from U1/U2 to U0 and enable those bits again
* after a transfer completes and there are no pending transfers
* on any of the enabled endpoints.
*
* This is the first half of that workaround.
*
* Refers to:
*
* STAR#9000446952: RTL: Device SS : if U1/U2 ->U0 takes >128us
* core send LGO_Ux entering U0
*/
if (dwc->revision < DWC3_REVISION_183A) {
if (next == DWC3_LINK_STATE_U0) {
u32 u1u2;
u32 reg;
switch (dwc->link_state) {
case DWC3_LINK_STATE_U1:
case DWC3_LINK_STATE_U2:
reg = dwc3_readl(dwc->regs, DWC3_DCTL);
u1u2 = reg & (DWC3_DCTL_INITU2ENA
| DWC3_DCTL_ACCEPTU2ENA
| DWC3_DCTL_INITU1ENA
| DWC3_DCTL_ACCEPTU1ENA);
if (!dwc->u1u2)
dwc->u1u2 = reg & u1u2;
reg &= ~u1u2;
dwc3_writel(dwc->regs, DWC3_DCTL, reg);
break;
default:
/* do nothing */
break;
}
}
}
switch (next) {
case DWC3_LINK_STATE_U1:
if (dwc->speed == USB_SPEED_SUPER)
dwc3_suspend_gadget(dwc);
break;
case DWC3_LINK_STATE_U2:
case DWC3_LINK_STATE_U3:
dwc3_suspend_gadget(dwc);
break;
case DWC3_LINK_STATE_RESUME:
dwc3_resume_gadget(dwc);
break;
default:
/* do nothing */
break;
}
dwc->link_state = next;
}
static void dwc3_gadget_suspend_interrupt(struct dwc3 *dwc,
unsigned int evtinfo)
{
enum dwc3_link_state next = evtinfo & DWC3_LINK_STATE_MASK;
if (dwc->link_state != next && next == DWC3_LINK_STATE_U3)
dwc3_suspend_gadget(dwc);
dwc->link_state = next;
}
static void dwc3_gadget_hibernation_interrupt(struct dwc3 *dwc,
unsigned int evtinfo)
{
unsigned int is_ss = evtinfo & BIT(4);
/**
* WORKAROUND: DWC3 revison 2.20a with hibernation support
* have a known issue which can cause USB CV TD.9.23 to fail
* randomly.
*
* Because of this issue, core could generate bogus hibernation
* events which SW needs to ignore.
*
* Refers to:
*
* STAR#9000546576: Device Mode Hibernation: Issue in USB 2.0
* Device Fallback from SuperSpeed
*/
if (is_ss ^ (dwc->speed == USB_SPEED_SUPER))
return;
/* enter hibernation here */
}
static void dwc3_gadget_interrupt(struct dwc3 *dwc,
const struct dwc3_event_devt *event)
{
switch (event->type) {
case DWC3_DEVICE_EVENT_DISCONNECT:
dwc3_gadget_disconnect_interrupt(dwc);
break;
case DWC3_DEVICE_EVENT_RESET:
dwc3_gadget_reset_interrupt(dwc);
break;
case DWC3_DEVICE_EVENT_CONNECT_DONE:
dwc3_gadget_conndone_interrupt(dwc);
break;
case DWC3_DEVICE_EVENT_WAKEUP:
dwc3_gadget_wakeup_interrupt(dwc);
break;
case DWC3_DEVICE_EVENT_HIBER_REQ:
if (dev_WARN_ONCE(dwc->dev, !dwc->has_hibernation,
"unexpected hibernation event\n"))
break;
dwc3_gadget_hibernation_interrupt(dwc, event->event_info);
break;
case DWC3_DEVICE_EVENT_LINK_STATUS_CHANGE:
dwc3_gadget_linksts_change_interrupt(dwc, event->event_info);
break;
case DWC3_DEVICE_EVENT_EOPF:
/* It changed to be suspend event for version 2.30a and above */
if (dwc->revision < DWC3_REVISION_230A) {
dwc3_trace(trace_dwc3_gadget, "End of Periodic Frame");
} else {
dwc3_trace(trace_dwc3_gadget, "U3/L1-L2 Suspend Event");
/*
* Ignore suspend event until the gadget enters into
* USB_STATE_CONFIGURED state.
*/
if (dwc->gadget.state >= USB_STATE_CONFIGURED)
dwc3_gadget_suspend_interrupt(dwc,
event->event_info);
}
break;
case DWC3_DEVICE_EVENT_SOF:
dwc3_trace(trace_dwc3_gadget, "Start of Periodic Frame");
break;
case DWC3_DEVICE_EVENT_ERRATIC_ERROR:
dwc3_trace(trace_dwc3_gadget, "Erratic Error");
break;
case DWC3_DEVICE_EVENT_CMD_CMPL:
dwc3_trace(trace_dwc3_gadget, "Command Complete");
break;
case DWC3_DEVICE_EVENT_OVERFLOW:
dwc3_trace(trace_dwc3_gadget, "Overflow");
break;
default:
dev_WARN(dwc->dev, "UNKNOWN IRQ %d\n", event->type);
}
}
static void dwc3_process_event_entry(struct dwc3 *dwc,
const union dwc3_event *event)
{
trace_dwc3_event(event->raw);
/* Endpoint IRQ, handle it and return early */
if (event->type.is_devspec == 0) {
/* depevt */
return dwc3_endpoint_interrupt(dwc, &event->depevt);
}
switch (event->type.type) {
case DWC3_EVENT_TYPE_DEV:
dwc3_gadget_interrupt(dwc, &event->devt);
break;
/* REVISIT what to do with Carkit and I2C events ? */
default:
dev_err(dwc->dev, "UNKNOWN IRQ type %d\n", event->raw);
}
}
static irqreturn_t dwc3_process_event_buf(struct dwc3_event_buffer *evt)
{
struct dwc3 *dwc = evt->dwc;
irqreturn_t ret = IRQ_NONE;
int left;
u32 reg;
left = evt->count;
if (!(evt->flags & DWC3_EVENT_PENDING))
return IRQ_NONE;
while (left > 0) {
union dwc3_event event;
event.raw = *(u32 *) (evt->buf + evt->lpos);
dwc3_process_event_entry(dwc, &event);
/*
* FIXME we wrap around correctly to the next entry as
* almost all entries are 4 bytes in size. There is one
* entry which has 12 bytes which is a regular entry
* followed by 8 bytes data. ATM I don't know how
* things are organized if we get next to the a
* boundary so I worry about that once we try to handle
* that.
*/
evt->lpos = (evt->lpos + 4) % DWC3_EVENT_BUFFERS_SIZE;
left -= 4;
dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(0), 4);
}
evt->count = 0;
evt->flags &= ~DWC3_EVENT_PENDING;
ret = IRQ_HANDLED;
/* Unmask interrupt */
reg = dwc3_readl(dwc->regs, DWC3_GEVNTSIZ(0));
reg &= ~DWC3_GEVNTSIZ_INTMASK;
dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(0), reg);
return ret;
}
static irqreturn_t dwc3_thread_interrupt(int irq, void *_evt)
{
struct dwc3_event_buffer *evt = _evt;
struct dwc3 *dwc = evt->dwc;
unsigned long flags;
irqreturn_t ret = IRQ_NONE;
spin_lock_irqsave(&dwc->lock, flags);
ret = dwc3_process_event_buf(evt);
spin_unlock_irqrestore(&dwc->lock, flags);
return ret;
}
static irqreturn_t dwc3_check_event_buf(struct dwc3_event_buffer *evt)
{
struct dwc3 *dwc = evt->dwc;
u32 count;
u32 reg;
if (pm_runtime_suspended(dwc->dev)) {
pm_runtime_get(dwc->dev);
disable_irq_nosync(dwc->irq_gadget);
dwc->pending_events = true;
return IRQ_HANDLED;
}
/*
* With PCIe legacy interrupt, test shows that top-half irq handler can
* be called again after HW interrupt deassertion. Check if bottom-half
* irq event handler completes before caching new event to prevent
* losing events.
*/
if (evt->flags & DWC3_EVENT_PENDING)
return IRQ_HANDLED;
count = dwc3_readl(dwc->regs, DWC3_GEVNTCOUNT(0));
count &= DWC3_GEVNTCOUNT_MASK;
if (!count)
return IRQ_NONE;
evt->count = count;
evt->flags |= DWC3_EVENT_PENDING;
/* Mask interrupt */
reg = dwc3_readl(dwc->regs, DWC3_GEVNTSIZ(0));
reg |= DWC3_GEVNTSIZ_INTMASK;
dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(0), reg);
return IRQ_WAKE_THREAD;
}
static irqreturn_t dwc3_interrupt(int irq, void *_evt)
{
struct dwc3_event_buffer *evt = _evt;
return dwc3_check_event_buf(evt);
}
/**
* dwc3_gadget_init - Initializes gadget related registers
* @dwc: pointer to our controller context structure
*
* Returns 0 on success otherwise negative errno.
*/
int dwc3_gadget_init(struct dwc3 *dwc)
{
int ret, irq;
struct platform_device *dwc3_pdev = to_platform_device(dwc->dev);
irq = platform_get_irq_byname(dwc3_pdev, "peripheral");
if (irq == -EPROBE_DEFER)
return irq;
if (irq <= 0) {
irq = platform_get_irq_byname(dwc3_pdev, "dwc_usb3");
if (irq == -EPROBE_DEFER)
return irq;
if (irq <= 0) {
irq = platform_get_irq(dwc3_pdev, 0);
if (irq <= 0) {
if (irq != -EPROBE_DEFER) {
dev_err(dwc->dev,
"missing peripheral IRQ\n");
}
if (!irq)
irq = -EINVAL;
return irq;
}
}
}
dwc->irq_gadget = irq;
dwc->ctrl_req = dma_alloc_coherent(dwc->dev, sizeof(*dwc->ctrl_req),
&dwc->ctrl_req_addr, GFP_KERNEL);
if (!dwc->ctrl_req) {
dev_err(dwc->dev, "failed to allocate ctrl request\n");
ret = -ENOMEM;
goto err0;
}
dwc->ep0_trb = dma_alloc_coherent(dwc->dev, sizeof(*dwc->ep0_trb) * 2,
&dwc->ep0_trb_addr, GFP_KERNEL);
if (!dwc->ep0_trb) {
dev_err(dwc->dev, "failed to allocate ep0 trb\n");
ret = -ENOMEM;
goto err1;
}
dwc->setup_buf = kzalloc(DWC3_EP0_BOUNCE_SIZE, GFP_KERNEL);
if (!dwc->setup_buf) {
ret = -ENOMEM;
goto err2;
}
dwc->ep0_bounce = dma_alloc_coherent(dwc->dev,
DWC3_EP0_BOUNCE_SIZE, &dwc->ep0_bounce_addr,
GFP_KERNEL);
if (!dwc->ep0_bounce) {
dev_err(dwc->dev, "failed to allocate ep0 bounce buffer\n");
ret = -ENOMEM;
goto err3;
}
dwc->zlp_buf = kzalloc(DWC3_ZLP_BUF_SIZE, GFP_KERNEL);
if (!dwc->zlp_buf) {
ret = -ENOMEM;
goto err4;
}
dwc->gadget.ops = &dwc3_gadget_ops;
dwc->gadget.speed = USB_SPEED_UNKNOWN;
dwc->gadget.sg_supported = true;
dwc->gadget.name = "dwc3-gadget";
/*
* FIXME We might be setting max_speed to <SUPER, however versions
* <2.20a of dwc3 have an issue with metastability (documented
* elsewhere in this driver) which tells us we can't set max speed to
* anything lower than SUPER.
*
* Because gadget.max_speed is only used by composite.c and function
* drivers (i.e. it won't go into dwc3's registers) we are allowing this
* to happen so we avoid sending SuperSpeed Capability descriptor
* together with our BOS descriptor as that could confuse host into
* thinking we can handle super speed.
*
* Note that, in fact, we won't even support GetBOS requests when speed
* is less than super speed because we don't have means, yet, to tell
* composite.c that we are USB 2.0 + LPM ECN.
*/
if (dwc->revision < DWC3_REVISION_220A)
dwc3_trace(trace_dwc3_gadget,
"Changing max_speed on rev %08x",
dwc->revision);
dwc->gadget.max_speed = dwc->maximum_speed;
/*
* Per databook, DWC3 needs buffer size to be aligned to MaxPacketSize
* on ep out.
*/
dwc->gadget.quirk_ep_out_aligned_size = true;
/*
* REVISIT: Here we should clear all pending IRQs to be
* sure we're starting from a well known location.
*/
ret = dwc3_gadget_init_endpoints(dwc);
if (ret)
goto err5;
ret = usb_add_gadget_udc(dwc->dev, &dwc->gadget);
if (ret) {
dev_err(dwc->dev, "failed to register udc\n");
goto err5;
}
return 0;
err5:
kfree(dwc->zlp_buf);
err4:
dwc3_gadget_free_endpoints(dwc);
dma_free_coherent(dwc->dev, DWC3_EP0_BOUNCE_SIZE,
dwc->ep0_bounce, dwc->ep0_bounce_addr);
err3:
kfree(dwc->setup_buf);
err2:
dma_free_coherent(dwc->dev, sizeof(*dwc->ep0_trb) * 2,
dwc->ep0_trb, dwc->ep0_trb_addr);
err1:
dma_free_coherent(dwc->dev, sizeof(*dwc->ctrl_req),
dwc->ctrl_req, dwc->ctrl_req_addr);
err0:
return ret;
}
/* -------------------------------------------------------------------------- */
void dwc3_gadget_exit(struct dwc3 *dwc)
{
usb_del_gadget_udc(&dwc->gadget);
dwc3_gadget_free_endpoints(dwc);
dma_free_coherent(dwc->dev, DWC3_EP0_BOUNCE_SIZE,
dwc->ep0_bounce, dwc->ep0_bounce_addr);
kfree(dwc->setup_buf);
kfree(dwc->zlp_buf);
dma_free_coherent(dwc->dev, sizeof(*dwc->ep0_trb) * 2,
dwc->ep0_trb, dwc->ep0_trb_addr);
dma_free_coherent(dwc->dev, sizeof(*dwc->ctrl_req),
dwc->ctrl_req, dwc->ctrl_req_addr);
}
int dwc3_gadget_suspend(struct dwc3 *dwc)
{
if (!dwc->gadget_driver)
return 0;
dwc3_gadget_run_stop(dwc, false, false);
dwc3_disconnect_gadget(dwc);
__dwc3_gadget_stop(dwc);
synchronize_irq(dwc->irq_gadget);
return 0;
}
int dwc3_gadget_resume(struct dwc3 *dwc)
{
int ret;
if (!dwc->gadget_driver)
return 0;
ret = __dwc3_gadget_start(dwc);
if (ret < 0)
goto err0;
ret = dwc3_gadget_run_stop(dwc, true, false);
if (ret < 0)
goto err1;
return 0;
err1:
__dwc3_gadget_stop(dwc);
err0:
return ret;
}
void dwc3_gadget_process_pending_events(struct dwc3 *dwc)
{
if (dwc->pending_events) {
dwc3_interrupt(dwc->irq_gadget, dwc->ev_buf);
dwc->pending_events = false;
enable_irq(dwc->irq_gadget);
}
}