xhci-dbgcap.c
/**
* xhci-dbgcap.c - xHCI debug capability support
*
* Copyright (C) 2017 Intel Corporation
*
* Author: Lu Baolu <baolu.lu@linux.intel.com>
*/
#include <linux/dma-mapping.h>
#include <linux/slab.h>
#include <linux/nls.h>
#include "xhci.h"
#include "xhci-trace.h"
#include "xhci-dbgcap.h"
static inline void *
dbc_dma_alloc_coherent(struct xhci_hcd *xhci, size_t size,
dma_addr_t *dma_handle, gfp_t flags)
{
void *vaddr;
vaddr = dma_alloc_coherent(xhci_to_hcd(xhci)->self.sysdev,
size, dma_handle, flags);
memset(vaddr, 0, size);
return vaddr;
}
static inline void
dbc_dma_free_coherent(struct xhci_hcd *xhci, size_t size,
void *cpu_addr, dma_addr_t dma_handle)
{
if (cpu_addr)
dma_free_coherent(xhci_to_hcd(xhci)->self.sysdev,
size, cpu_addr, dma_handle);
}
static u32 xhci_dbc_populate_strings(struct dbc_str_descs *strings)
{
struct usb_string_descriptor *s_desc;
u32 string_length;
/* Serial string: */
s_desc = (struct usb_string_descriptor *)strings->serial;
utf8s_to_utf16s(DBC_STRING_SERIAL, strlen(DBC_STRING_SERIAL),
UTF16_LITTLE_ENDIAN, (wchar_t *)s_desc->wData,
DBC_MAX_STRING_LENGTH);
s_desc->bLength = (strlen(DBC_STRING_SERIAL) + 1) * 2;
s_desc->bDescriptorType = USB_DT_STRING;
string_length = s_desc->bLength;
string_length <<= 8;
/* Product string: */
s_desc = (struct usb_string_descriptor *)strings->product;
utf8s_to_utf16s(DBC_STRING_PRODUCT, strlen(DBC_STRING_PRODUCT),
UTF16_LITTLE_ENDIAN, (wchar_t *)s_desc->wData,
DBC_MAX_STRING_LENGTH);
s_desc->bLength = (strlen(DBC_STRING_PRODUCT) + 1) * 2;
s_desc->bDescriptorType = USB_DT_STRING;
string_length += s_desc->bLength;
string_length <<= 8;
/* Manufacture string: */
s_desc = (struct usb_string_descriptor *)strings->manufacturer;
utf8s_to_utf16s(DBC_STRING_MANUFACTURER,
strlen(DBC_STRING_MANUFACTURER),
UTF16_LITTLE_ENDIAN, (wchar_t *)s_desc->wData,
DBC_MAX_STRING_LENGTH);
s_desc->bLength = (strlen(DBC_STRING_MANUFACTURER) + 1) * 2;
s_desc->bDescriptorType = USB_DT_STRING;
string_length += s_desc->bLength;
string_length <<= 8;
/* String0: */
strings->string0[0] = 4;
strings->string0[1] = USB_DT_STRING;
strings->string0[2] = 0x09;
strings->string0[3] = 0x04;
string_length += 4;
return string_length;
}
static void xhci_dbc_init_contexts(struct xhci_hcd *xhci, u32 string_length)
{
struct xhci_dbc *dbc;
struct dbc_info_context *info;
struct xhci_ep_ctx *ep_ctx;
u32 dev_info;
dma_addr_t deq, dma;
unsigned int max_burst;
dbc = xhci->dbc;
if (!dbc)
return;
/* Populate info Context: */
info = (struct dbc_info_context *)dbc->ctx->bytes;
dma = dbc->string_dma;
info->string0 = cpu_to_le64(dma);
info->manufacturer = cpu_to_le64(dma + DBC_MAX_STRING_LENGTH);
info->product = cpu_to_le64(dma + DBC_MAX_STRING_LENGTH * 2);
info->serial = cpu_to_le64(dma + DBC_MAX_STRING_LENGTH * 3);
info->length = cpu_to_le32(string_length);
/* Populate bulk out endpoint context: */
ep_ctx = dbc_bulkout_ctx(dbc);
max_burst = DBC_CTRL_MAXBURST(readl(&dbc->regs->control));
deq = dbc_bulkout_enq(dbc);
ep_ctx->ep_info = 0;
ep_ctx->ep_info2 = dbc_epctx_info2(BULK_OUT_EP, 1024, max_burst);
ep_ctx->deq = cpu_to_le64(deq | dbc->ring_out->cycle_state);
/* Populate bulk in endpoint context: */
ep_ctx = dbc_bulkin_ctx(dbc);
deq = dbc_bulkin_enq(dbc);
ep_ctx->ep_info = 0;
ep_ctx->ep_info2 = dbc_epctx_info2(BULK_IN_EP, 1024, max_burst);
ep_ctx->deq = cpu_to_le64(deq | dbc->ring_in->cycle_state);
/* Set DbC context and info registers: */
xhci_write_64(xhci, dbc->ctx->dma, &dbc->regs->dccp);
dev_info = cpu_to_le32((DBC_VENDOR_ID << 16) | DBC_PROTOCOL);
writel(dev_info, &dbc->regs->devinfo1);
dev_info = cpu_to_le32((DBC_DEVICE_REV << 16) | DBC_PRODUCT_ID);
writel(dev_info, &dbc->regs->devinfo2);
}
static void xhci_dbc_giveback(struct dbc_request *req, int status)
__releases(&dbc->lock)
__acquires(&dbc->lock)
{
struct dbc_ep *dep = req->dep;
struct xhci_dbc *dbc = dep->dbc;
struct xhci_hcd *xhci = dbc->xhci;
struct device *dev = xhci_to_hcd(dbc->xhci)->self.sysdev;
list_del_init(&req->list_pending);
req->trb_dma = 0;
req->trb = NULL;
if (req->status == -EINPROGRESS)
req->status = status;
trace_xhci_dbc_giveback_request(req);
dma_unmap_single(dev,
req->dma,
req->length,
dbc_ep_dma_direction(dep));
/* Give back the transfer request: */
spin_unlock(&dbc->lock);
req->complete(xhci, req);
spin_lock(&dbc->lock);
}
static void xhci_dbc_flush_single_request(struct dbc_request *req)
{
union xhci_trb *trb = req->trb;
trb->generic.field[0] = 0;
trb->generic.field[1] = 0;
trb->generic.field[2] = 0;
trb->generic.field[3] &= cpu_to_le32(TRB_CYCLE);
trb->generic.field[3] |= cpu_to_le32(TRB_TYPE(TRB_TR_NOOP));
xhci_dbc_giveback(req, -ESHUTDOWN);
}
static void xhci_dbc_flush_endpoint_requests(struct dbc_ep *dep)
{
struct dbc_request *req, *tmp;
list_for_each_entry_safe(req, tmp, &dep->list_pending, list_pending)
xhci_dbc_flush_single_request(req);
}
static void xhci_dbc_flush_reqests(struct xhci_dbc *dbc)
{
xhci_dbc_flush_endpoint_requests(&dbc->eps[BULK_OUT]);
xhci_dbc_flush_endpoint_requests(&dbc->eps[BULK_IN]);
}
struct dbc_request *
dbc_alloc_request(struct dbc_ep *dep, gfp_t gfp_flags)
{
struct dbc_request *req;
req = kzalloc(sizeof(*req), gfp_flags);
if (!req)
return NULL;
req->dep = dep;
INIT_LIST_HEAD(&req->list_pending);
INIT_LIST_HEAD(&req->list_pool);
req->direction = dep->direction;
trace_xhci_dbc_alloc_request(req);
return req;
}
void
dbc_free_request(struct dbc_ep *dep, struct dbc_request *req)
{
trace_xhci_dbc_free_request(req);
kfree(req);
}
static void
xhci_dbc_queue_trb(struct xhci_ring *ring, u32 field1,
u32 field2, u32 field3, u32 field4)
{
union xhci_trb *trb, *next;
trb = ring->enqueue;
trb->generic.field[0] = cpu_to_le32(field1);
trb->generic.field[1] = cpu_to_le32(field2);
trb->generic.field[2] = cpu_to_le32(field3);
trb->generic.field[3] = cpu_to_le32(field4);
trace_xhci_dbc_gadget_ep_queue(ring, &trb->generic);
ring->num_trbs_free--;
next = ++(ring->enqueue);
if (TRB_TYPE_LINK_LE32(next->link.control)) {
next->link.control ^= cpu_to_le32(TRB_CYCLE);
ring->enqueue = ring->enq_seg->trbs;
ring->cycle_state ^= 1;
}
}
static int xhci_dbc_queue_bulk_tx(struct dbc_ep *dep,
struct dbc_request *req)
{
u64 addr;
union xhci_trb *trb;
unsigned int num_trbs;
struct xhci_dbc *dbc = dep->dbc;
struct xhci_ring *ring = dep->ring;
u32 length, control, cycle;
num_trbs = count_trbs(req->dma, req->length);
WARN_ON(num_trbs != 1);
if (ring->num_trbs_free < num_trbs)
return -EBUSY;
addr = req->dma;
trb = ring->enqueue;
cycle = ring->cycle_state;
length = TRB_LEN(req->length);
control = TRB_TYPE(TRB_NORMAL) | TRB_IOC;
if (cycle)
control &= cpu_to_le32(~TRB_CYCLE);
else
control |= cpu_to_le32(TRB_CYCLE);
req->trb = ring->enqueue;
req->trb_dma = xhci_trb_virt_to_dma(ring->enq_seg, ring->enqueue);
xhci_dbc_queue_trb(ring,
lower_32_bits(addr),
upper_32_bits(addr),
length, control);
/*
* Add a barrier between writes of trb fields and flipping
* the cycle bit:
*/
wmb();
if (cycle)
trb->generic.field[3] |= cpu_to_le32(TRB_CYCLE);
else
trb->generic.field[3] &= cpu_to_le32(~TRB_CYCLE);
writel(DBC_DOOR_BELL_TARGET(dep->direction), &dbc->regs->doorbell);
return 0;
}
static int
dbc_ep_do_queue(struct dbc_ep *dep, struct dbc_request *req)
{
int ret;
struct device *dev;
struct xhci_dbc *dbc = dep->dbc;
struct xhci_hcd *xhci = dbc->xhci;
dev = xhci_to_hcd(xhci)->self.sysdev;
if (!req->length || !req->buf)
return -EINVAL;
req->actual = 0;
req->status = -EINPROGRESS;
req->dma = dma_map_single(dev,
req->buf,
req->length,
dbc_ep_dma_direction(dep));
if (dma_mapping_error(dev, req->dma)) {
xhci_err(xhci, "failed to map buffer\n");
return -EFAULT;
}
ret = xhci_dbc_queue_bulk_tx(dep, req);
if (ret) {
xhci_err(xhci, "failed to queue trbs\n");
dma_unmap_single(dev,
req->dma,
req->length,
dbc_ep_dma_direction(dep));
return -EFAULT;
}
list_add_tail(&req->list_pending, &dep->list_pending);
return 0;
}
int dbc_ep_queue(struct dbc_ep *dep, struct dbc_request *req,
gfp_t gfp_flags)
{
unsigned long flags;
struct xhci_dbc *dbc = dep->dbc;
int ret = -ESHUTDOWN;
spin_lock_irqsave(&dbc->lock, flags);
if (dbc->state == DS_CONFIGURED)
ret = dbc_ep_do_queue(dep, req);
spin_unlock_irqrestore(&dbc->lock, flags);
mod_delayed_work(system_wq, &dbc->event_work, 0);
trace_xhci_dbc_queue_request(req);
return ret;
}
static inline void xhci_dbc_do_eps_init(struct xhci_hcd *xhci, bool direction)
{
struct dbc_ep *dep;
struct xhci_dbc *dbc = xhci->dbc;
dep = &dbc->eps[direction];
dep->dbc = dbc;
dep->direction = direction;
dep->ring = direction ? dbc->ring_in : dbc->ring_out;
INIT_LIST_HEAD(&dep->list_pending);
}
static void xhci_dbc_eps_init(struct xhci_hcd *xhci)
{
xhci_dbc_do_eps_init(xhci, BULK_OUT);
xhci_dbc_do_eps_init(xhci, BULK_IN);
}
static void xhci_dbc_eps_exit(struct xhci_hcd *xhci)
{
struct xhci_dbc *dbc = xhci->dbc;
memset(dbc->eps, 0, sizeof(struct dbc_ep) * ARRAY_SIZE(dbc->eps));
}
static int xhci_dbc_mem_init(struct xhci_hcd *xhci, gfp_t flags)
{
int ret;
dma_addr_t deq;
u32 string_length;
struct xhci_dbc *dbc = xhci->dbc;
/* Allocate various rings for events and transfers: */
dbc->ring_evt = xhci_ring_alloc(xhci, 1, 1, TYPE_EVENT, 0, flags);
if (!dbc->ring_evt)
goto evt_fail;
dbc->ring_in = xhci_ring_alloc(xhci, 1, 1, TYPE_BULK, 0, flags);
if (!dbc->ring_in)
goto in_fail;
dbc->ring_out = xhci_ring_alloc(xhci, 1, 1, TYPE_BULK, 0, flags);
if (!dbc->ring_out)
goto out_fail;
/* Allocate and populate ERST: */
ret = xhci_alloc_erst(xhci, dbc->ring_evt, &dbc->erst, flags);
if (ret)
goto erst_fail;
/* Allocate context data structure: */
dbc->ctx = xhci_alloc_container_ctx(xhci, XHCI_CTX_TYPE_DEVICE, flags);
if (!dbc->ctx)
goto ctx_fail;
/* Allocate the string table: */
dbc->string_size = sizeof(struct dbc_str_descs);
dbc->string = dbc_dma_alloc_coherent(xhci,
dbc->string_size,
&dbc->string_dma,
flags);
if (!dbc->string)
goto string_fail;
/* Setup ERST register: */
writel(dbc->erst.erst_size, &dbc->regs->ersts);
xhci_write_64(xhci, dbc->erst.erst_dma_addr, &dbc->regs->erstba);
deq = xhci_trb_virt_to_dma(dbc->ring_evt->deq_seg,
dbc->ring_evt->dequeue);
xhci_write_64(xhci, deq, &dbc->regs->erdp);
/* Setup strings and contexts: */
string_length = xhci_dbc_populate_strings(dbc->string);
xhci_dbc_init_contexts(xhci, string_length);
mmiowb();
xhci_dbc_eps_init(xhci);
dbc->state = DS_INITIALIZED;
return 0;
string_fail:
xhci_free_container_ctx(xhci, dbc->ctx);
dbc->ctx = NULL;
ctx_fail:
xhci_free_erst(xhci, &dbc->erst);
erst_fail:
xhci_ring_free(xhci, dbc->ring_out);
dbc->ring_out = NULL;
out_fail:
xhci_ring_free(xhci, dbc->ring_in);
dbc->ring_in = NULL;
in_fail:
xhci_ring_free(xhci, dbc->ring_evt);
dbc->ring_evt = NULL;
evt_fail:
return -ENOMEM;
}
static void xhci_dbc_mem_cleanup(struct xhci_hcd *xhci)
{
struct xhci_dbc *dbc = xhci->dbc;
if (!dbc)
return;
xhci_dbc_eps_exit(xhci);
if (dbc->string) {
dbc_dma_free_coherent(xhci,
dbc->string_size,
dbc->string, dbc->string_dma);
dbc->string = NULL;
}
xhci_free_container_ctx(xhci, dbc->ctx);
dbc->ctx = NULL;
xhci_free_erst(xhci, &dbc->erst);
xhci_ring_free(xhci, dbc->ring_out);
xhci_ring_free(xhci, dbc->ring_in);
xhci_ring_free(xhci, dbc->ring_evt);
dbc->ring_in = NULL;
dbc->ring_out = NULL;
dbc->ring_evt = NULL;
}
static int xhci_do_dbc_start(struct xhci_hcd *xhci)
{
int ret;
u32 ctrl;
struct xhci_dbc *dbc = xhci->dbc;
if (dbc->state != DS_DISABLED)
return -EINVAL;
writel(0, &dbc->regs->control);
ret = xhci_handshake(&dbc->regs->control,
DBC_CTRL_DBC_ENABLE,
0, 1000);
if (ret)
return ret;
ret = xhci_dbc_mem_init(xhci, GFP_ATOMIC);
if (ret)
return ret;
ctrl = readl(&dbc->regs->control);
writel(ctrl | DBC_CTRL_DBC_ENABLE | DBC_CTRL_PORT_ENABLE,
&dbc->regs->control);
ret = xhci_handshake(&dbc->regs->control,
DBC_CTRL_DBC_ENABLE,
DBC_CTRL_DBC_ENABLE, 1000);
if (ret)
return ret;
dbc->state = DS_ENABLED;
return 0;
}
static void xhci_do_dbc_stop(struct xhci_hcd *xhci)
{
struct xhci_dbc *dbc = xhci->dbc;
if (dbc->state == DS_DISABLED)
return;
writel(0, &dbc->regs->control);
xhci_dbc_mem_cleanup(xhci);
dbc->state = DS_DISABLED;
}
static int xhci_dbc_start(struct xhci_hcd *xhci)
{
int ret;
unsigned long flags;
struct xhci_dbc *dbc = xhci->dbc;
WARN_ON(!dbc);
pm_runtime_get_sync(xhci_to_hcd(xhci)->self.controller);
spin_lock_irqsave(&dbc->lock, flags);
ret = xhci_do_dbc_start(xhci);
spin_unlock_irqrestore(&dbc->lock, flags);
if (ret) {
pm_runtime_put(xhci_to_hcd(xhci)->self.controller);
return ret;
}
return mod_delayed_work(system_wq, &dbc->event_work, 1);
}
static void xhci_dbc_stop(struct xhci_hcd *xhci)
{
unsigned long flags;
struct xhci_dbc *dbc = xhci->dbc;
struct dbc_port *port = &dbc->port;
WARN_ON(!dbc);
cancel_delayed_work_sync(&dbc->event_work);
if (port->registered)
xhci_dbc_tty_unregister_device(xhci);
spin_lock_irqsave(&dbc->lock, flags);
xhci_do_dbc_stop(xhci);
spin_unlock_irqrestore(&dbc->lock, flags);
pm_runtime_put_sync(xhci_to_hcd(xhci)->self.controller);
}
static void
dbc_handle_port_status(struct xhci_hcd *xhci, union xhci_trb *event)
{
u32 portsc;
struct xhci_dbc *dbc = xhci->dbc;
portsc = readl(&dbc->regs->portsc);
if (portsc & DBC_PORTSC_CONN_CHANGE)
xhci_info(xhci, "DbC port connect change\n");
if (portsc & DBC_PORTSC_RESET_CHANGE)
xhci_info(xhci, "DbC port reset change\n");
if (portsc & DBC_PORTSC_LINK_CHANGE)
xhci_info(xhci, "DbC port link status change\n");
if (portsc & DBC_PORTSC_CONFIG_CHANGE)
xhci_info(xhci, "DbC config error change\n");
/* Port reset change bit will be cleared in other place: */
writel(portsc & ~DBC_PORTSC_RESET_CHANGE, &dbc->regs->portsc);
}
static void dbc_handle_xfer_event(struct xhci_hcd *xhci, union xhci_trb *event)
{
struct dbc_ep *dep;
struct xhci_ring *ring;
int ep_id;
int status;
u32 comp_code;
size_t remain_length;
struct dbc_request *req = NULL, *r;
comp_code = GET_COMP_CODE(le32_to_cpu(event->generic.field[2]));
remain_length = EVENT_TRB_LEN(le32_to_cpu(event->generic.field[2]));
ep_id = TRB_TO_EP_ID(le32_to_cpu(event->generic.field[3]));
dep = (ep_id == EPID_OUT) ?
get_out_ep(xhci) : get_in_ep(xhci);
ring = dep->ring;
switch (comp_code) {
case COMP_SUCCESS:
remain_length = 0;
/* FALLTHROUGH */
case COMP_SHORT_PACKET:
status = 0;
break;
case COMP_TRB_ERROR:
case COMP_BABBLE_DETECTED_ERROR:
case COMP_USB_TRANSACTION_ERROR:
case COMP_STALL_ERROR:
xhci_warn(xhci, "tx error %d detected\n", comp_code);
status = -comp_code;
break;
default:
xhci_err(xhci, "unknown tx error %d\n", comp_code);
status = -comp_code;
break;
}
/* Match the pending request: */
list_for_each_entry(r, &dep->list_pending, list_pending) {
if (r->trb_dma == event->trans_event.buffer) {
req = r;
break;
}
}
if (!req) {
xhci_warn(xhci, "no matched request\n");
return;
}
trace_xhci_dbc_handle_transfer(ring, &req->trb->generic);
ring->num_trbs_free++;
req->actual = req->length - remain_length;
xhci_dbc_giveback(req, status);
}
static enum evtreturn xhci_dbc_do_handle_events(struct xhci_dbc *dbc)
{
dma_addr_t deq;
struct dbc_ep *dep;
union xhci_trb *evt;
u32 ctrl, portsc;
struct xhci_hcd *xhci = dbc->xhci;
bool update_erdp = false;
/* DbC state machine: */
switch (dbc->state) {
case DS_DISABLED:
case DS_INITIALIZED:
return EVT_ERR;
case DS_ENABLED:
portsc = readl(&dbc->regs->portsc);
if (portsc & DBC_PORTSC_CONN_STATUS) {
dbc->state = DS_CONNECTED;
xhci_info(xhci, "DbC connected\n");
}
return EVT_DONE;
case DS_CONNECTED:
ctrl = readl(&dbc->regs->control);
if (ctrl & DBC_CTRL_DBC_RUN) {
dbc->state = DS_CONFIGURED;
xhci_info(xhci, "DbC configured\n");
portsc = readl(&dbc->regs->portsc);
writel(portsc, &dbc->regs->portsc);
return EVT_GSER;
}
return EVT_DONE;
case DS_CONFIGURED:
/* Handle cable unplug event: */
portsc = readl(&dbc->regs->portsc);
if (!(portsc & DBC_PORTSC_PORT_ENABLED) &&
!(portsc & DBC_PORTSC_CONN_STATUS)) {
xhci_info(xhci, "DbC cable unplugged\n");
dbc->state = DS_ENABLED;
xhci_dbc_flush_reqests(dbc);
return EVT_DISC;
}
/* Handle debug port reset event: */
if (portsc & DBC_PORTSC_RESET_CHANGE) {
xhci_info(xhci, "DbC port reset\n");
writel(portsc, &dbc->regs->portsc);
dbc->state = DS_ENABLED;
xhci_dbc_flush_reqests(dbc);
return EVT_DISC;
}
/* Handle endpoint stall event: */
ctrl = readl(&dbc->regs->control);
if ((ctrl & DBC_CTRL_HALT_IN_TR) ||
(ctrl & DBC_CTRL_HALT_OUT_TR)) {
xhci_info(xhci, "DbC Endpoint stall\n");
dbc->state = DS_STALLED;
if (ctrl & DBC_CTRL_HALT_IN_TR) {
dep = get_in_ep(xhci);
xhci_dbc_flush_endpoint_requests(dep);
}
if (ctrl & DBC_CTRL_HALT_OUT_TR) {
dep = get_out_ep(xhci);
xhci_dbc_flush_endpoint_requests(dep);
}
return EVT_DONE;
}
/* Clear DbC run change bit: */
if (ctrl & DBC_CTRL_DBC_RUN_CHANGE) {
writel(ctrl, &dbc->regs->control);
ctrl = readl(&dbc->regs->control);
}
break;
case DS_STALLED:
ctrl = readl(&dbc->regs->control);
if (!(ctrl & DBC_CTRL_HALT_IN_TR) &&
!(ctrl & DBC_CTRL_HALT_OUT_TR) &&
(ctrl & DBC_CTRL_DBC_RUN)) {
dbc->state = DS_CONFIGURED;
break;
}
return EVT_DONE;
default:
xhci_err(xhci, "Unknown DbC state %d\n", dbc->state);
break;
}
/* Handle the events in the event ring: */
evt = dbc->ring_evt->dequeue;
while ((le32_to_cpu(evt->event_cmd.flags) & TRB_CYCLE) ==
dbc->ring_evt->cycle_state) {
/*
* Add a barrier between reading the cycle flag and any
* reads of the event's flags/data below:
*/
rmb();
trace_xhci_dbc_handle_event(dbc->ring_evt, &evt->generic);
switch (le32_to_cpu(evt->event_cmd.flags) & TRB_TYPE_BITMASK) {
case TRB_TYPE(TRB_PORT_STATUS):
dbc_handle_port_status(xhci, evt);
break;
case TRB_TYPE(TRB_TRANSFER):
dbc_handle_xfer_event(xhci, evt);
break;
default:
break;
}
inc_deq(xhci, dbc->ring_evt);
evt = dbc->ring_evt->dequeue;
update_erdp = true;
}
/* Update event ring dequeue pointer: */
if (update_erdp) {
deq = xhci_trb_virt_to_dma(dbc->ring_evt->deq_seg,
dbc->ring_evt->dequeue);
xhci_write_64(xhci, deq, &dbc->regs->erdp);
}
return EVT_DONE;
}
static void xhci_dbc_handle_events(struct work_struct *work)
{
int ret;
enum evtreturn evtr;
struct xhci_dbc *dbc;
unsigned long flags;
struct xhci_hcd *xhci;
dbc = container_of(to_delayed_work(work), struct xhci_dbc, event_work);
xhci = dbc->xhci;
spin_lock_irqsave(&dbc->lock, flags);
evtr = xhci_dbc_do_handle_events(dbc);
spin_unlock_irqrestore(&dbc->lock, flags);
switch (evtr) {
case EVT_GSER:
ret = xhci_dbc_tty_register_device(xhci);
if (ret) {
xhci_err(xhci, "failed to alloc tty device\n");
break;
}
xhci_info(xhci, "DbC now attached to /dev/ttyDBC0\n");
break;
case EVT_DISC:
xhci_dbc_tty_unregister_device(xhci);
break;
case EVT_DONE:
break;
default:
xhci_info(xhci, "stop handling dbc events\n");
return;
}
mod_delayed_work(system_wq, &dbc->event_work, 1);
}
static void xhci_do_dbc_exit(struct xhci_hcd *xhci)
{
unsigned long flags;
spin_lock_irqsave(&xhci->lock, flags);
kfree(xhci->dbc);
xhci->dbc = NULL;
spin_unlock_irqrestore(&xhci->lock, flags);
}
static int xhci_do_dbc_init(struct xhci_hcd *xhci)
{
u32 reg;
struct xhci_dbc *dbc;
unsigned long flags;
void __iomem *base;
int dbc_cap_offs;
base = &xhci->cap_regs->hc_capbase;
dbc_cap_offs = xhci_find_next_ext_cap(base, 0, XHCI_EXT_CAPS_DEBUG);
if (!dbc_cap_offs)
return -ENODEV;
dbc = kzalloc(sizeof(*dbc), GFP_KERNEL);
if (!dbc)
return -ENOMEM;
dbc->regs = base + dbc_cap_offs;
/* We will avoid using DbC in xhci driver if it's in use. */
reg = readl(&dbc->regs->control);
if (reg & DBC_CTRL_DBC_ENABLE) {
kfree(dbc);
return -EBUSY;
}
spin_lock_irqsave(&xhci->lock, flags);
if (xhci->dbc) {
spin_unlock_irqrestore(&xhci->lock, flags);
kfree(dbc);
return -EBUSY;
}
xhci->dbc = dbc;
spin_unlock_irqrestore(&xhci->lock, flags);
dbc->xhci = xhci;
INIT_DELAYED_WORK(&dbc->event_work, xhci_dbc_handle_events);
spin_lock_init(&dbc->lock);
return 0;
}
static ssize_t dbc_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
const char *p;
struct xhci_dbc *dbc;
struct xhci_hcd *xhci;
xhci = hcd_to_xhci(dev_get_drvdata(dev));
dbc = xhci->dbc;
switch (dbc->state) {
case DS_DISABLED:
p = "disabled";
break;
case DS_INITIALIZED:
p = "initialized";
break;
case DS_ENABLED:
p = "enabled";
break;
case DS_CONNECTED:
p = "connected";
break;
case DS_CONFIGURED:
p = "configured";
break;
case DS_STALLED:
p = "stalled";
break;
default:
p = "unknown";
}
return sprintf(buf, "%s\n", p);
}
static ssize_t dbc_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct xhci_dbc *dbc;
struct xhci_hcd *xhci;
xhci = hcd_to_xhci(dev_get_drvdata(dev));
dbc = xhci->dbc;
if (!strncmp(buf, "enable", 6))
xhci_dbc_start(xhci);
else if (!strncmp(buf, "disable", 7))
xhci_dbc_stop(xhci);
else
return -EINVAL;
return count;
}
static DEVICE_ATTR_RW(dbc);
int xhci_dbc_init(struct xhci_hcd *xhci)
{
int ret;
struct device *dev = xhci_to_hcd(xhci)->self.controller;
ret = xhci_do_dbc_init(xhci);
if (ret)
goto init_err3;
ret = xhci_dbc_tty_register_driver(xhci);
if (ret)
goto init_err2;
ret = device_create_file(dev, &dev_attr_dbc);
if (ret)
goto init_err1;
return 0;
init_err1:
xhci_dbc_tty_unregister_driver();
init_err2:
xhci_do_dbc_exit(xhci);
init_err3:
return ret;
}
void xhci_dbc_exit(struct xhci_hcd *xhci)
{
struct device *dev = xhci_to_hcd(xhci)->self.controller;
if (!xhci->dbc)
return;
device_remove_file(dev, &dev_attr_dbc);
xhci_dbc_tty_unregister_driver();
xhci_dbc_stop(xhci);
xhci_do_dbc_exit(xhci);
}
#ifdef CONFIG_PM
int xhci_dbc_suspend(struct xhci_hcd *xhci)
{
struct xhci_dbc *dbc = xhci->dbc;
if (!dbc)
return 0;
if (dbc->state == DS_CONFIGURED)
dbc->resume_required = 1;
xhci_dbc_stop(xhci);
return 0;
}
int xhci_dbc_resume(struct xhci_hcd *xhci)
{
int ret = 0;
struct xhci_dbc *dbc = xhci->dbc;
if (!dbc)
return 0;
if (dbc->resume_required) {
dbc->resume_required = 0;
xhci_dbc_start(xhci);
}
return ret;
}
#endif /* CONFIG_PM */