u-boot-brain/drivers/usb/gadget/ci_udc.c
Stephen Warren 8aac6e9c53 usb: ci_udc: set ep->req.actual after transfer
At least drivers/usb/gadget/storage_common.c expects that ep->req.actual
contain the number of bytes actually transferred. (At least in practice,
I observed it failing to work correctly unless this was the case).

However, ci_udc.c modifies ep->req.length instead. I assume that .length
 is supposed to represent the allocated buffer size, whereas .actual is
supposed to represent the actual number of bytes transferred. In the OUT
transaction case, this may happen simply because the host sends a smaller
 packet than the max possible size, which is quite legal. In the IN case,
transferring fewer bytes than requested could presumably happen as an
error.

Modify handle_ep_complete() to write to .actual rather than modifying
.length.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
2014-04-30 10:30:57 +02:00

741 lines
19 KiB
C

/*
* Copyright 2011, Marvell Semiconductor Inc.
* Lei Wen <leiwen@marvell.com>
*
* SPDX-License-Identifier: GPL-2.0+
*
* Back ported to the 8xx platform (from the 8260 platform) by
* Murray.Jensen@cmst.csiro.au, 27-Jan-01.
*/
#include <common.h>
#include <command.h>
#include <config.h>
#include <net.h>
#include <malloc.h>
#include <asm/byteorder.h>
#include <asm/errno.h>
#include <asm/io.h>
#include <asm/unaligned.h>
#include <linux/types.h>
#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>
#include <usb/ci_udc.h>
#include "../host/ehci.h"
#include "ci_udc.h"
/*
* Check if the system has too long cachelines. If the cachelines are
* longer then 128b, the driver will not be able flush/invalidate data
* cache over separate QH entries. We use 128b because one QH entry is
* 64b long and there are always two QH list entries for each endpoint.
*/
#if ARCH_DMA_MINALIGN > 128
#error This driver can not work on systems with caches longer than 128b
#endif
#ifndef DEBUG
#define DBG(x...) do {} while (0)
#else
#define DBG(x...) printf(x)
static const char *reqname(unsigned r)
{
switch (r) {
case USB_REQ_GET_STATUS: return "GET_STATUS";
case USB_REQ_CLEAR_FEATURE: return "CLEAR_FEATURE";
case USB_REQ_SET_FEATURE: return "SET_FEATURE";
case USB_REQ_SET_ADDRESS: return "SET_ADDRESS";
case USB_REQ_GET_DESCRIPTOR: return "GET_DESCRIPTOR";
case USB_REQ_SET_DESCRIPTOR: return "SET_DESCRIPTOR";
case USB_REQ_GET_CONFIGURATION: return "GET_CONFIGURATION";
case USB_REQ_SET_CONFIGURATION: return "SET_CONFIGURATION";
case USB_REQ_GET_INTERFACE: return "GET_INTERFACE";
case USB_REQ_SET_INTERFACE: return "SET_INTERFACE";
default: return "*UNKNOWN*";
}
}
#endif
static struct usb_endpoint_descriptor ep0_out_desc = {
.bLength = sizeof(struct usb_endpoint_descriptor),
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = 0,
.bmAttributes = USB_ENDPOINT_XFER_CONTROL,
};
static struct usb_endpoint_descriptor ep0_in_desc = {
.bLength = sizeof(struct usb_endpoint_descriptor),
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = USB_DIR_IN,
.bmAttributes = USB_ENDPOINT_XFER_CONTROL,
};
static int ci_pullup(struct usb_gadget *gadget, int is_on);
static int ci_ep_enable(struct usb_ep *ep,
const struct usb_endpoint_descriptor *desc);
static int ci_ep_disable(struct usb_ep *ep);
static int ci_ep_queue(struct usb_ep *ep,
struct usb_request *req, gfp_t gfp_flags);
static struct usb_request *
ci_ep_alloc_request(struct usb_ep *ep, unsigned int gfp_flags);
static void ci_ep_free_request(struct usb_ep *ep, struct usb_request *_req);
static struct usb_gadget_ops ci_udc_ops = {
.pullup = ci_pullup,
};
static struct usb_ep_ops ci_ep_ops = {
.enable = ci_ep_enable,
.disable = ci_ep_disable,
.queue = ci_ep_queue,
.alloc_request = ci_ep_alloc_request,
.free_request = ci_ep_free_request,
};
/* Init values for USB endpoints. */
static const struct usb_ep ci_ep_init[2] = {
[0] = { /* EP 0 */
.maxpacket = 64,
.name = "ep0",
.ops = &ci_ep_ops,
},
[1] = { /* EP 1..n */
.maxpacket = 512,
.name = "ep-",
.ops = &ci_ep_ops,
},
};
static struct ci_drv controller = {
.gadget = {
.name = "ci_udc",
.ops = &ci_udc_ops,
.is_dualspeed = 1,
},
};
/**
* ci_get_qh() - return queue head for endpoint
* @ep_num: Endpoint number
* @dir_in: Direction of the endpoint (IN = 1, OUT = 0)
*
* This function returns the QH associated with particular endpoint
* and it's direction.
*/
static struct ept_queue_head *ci_get_qh(int ep_num, int dir_in)
{
return &controller.epts[(ep_num * 2) + dir_in];
}
/**
* ci_get_qtd() - return queue item for endpoint
* @ep_num: Endpoint number
* @dir_in: Direction of the endpoint (IN = 1, OUT = 0)
*
* This function returns the QH associated with particular endpoint
* and it's direction.
*/
static struct ept_queue_item *ci_get_qtd(int ep_num, int dir_in)
{
return controller.items[(ep_num * 2) + dir_in];
}
/**
* ci_flush_qh - flush cache over queue head
* @ep_num: Endpoint number
*
* This function flushes cache over QH for particular endpoint.
*/
static void ci_flush_qh(int ep_num)
{
struct ept_queue_head *head = ci_get_qh(ep_num, 0);
const uint32_t start = (uint32_t)head;
const uint32_t end = start + 2 * sizeof(*head);
flush_dcache_range(start, end);
}
/**
* ci_invalidate_qh - invalidate cache over queue head
* @ep_num: Endpoint number
*
* This function invalidates cache over QH for particular endpoint.
*/
static void ci_invalidate_qh(int ep_num)
{
struct ept_queue_head *head = ci_get_qh(ep_num, 0);
uint32_t start = (uint32_t)head;
uint32_t end = start + 2 * sizeof(*head);
invalidate_dcache_range(start, end);
}
/**
* ci_flush_qtd - flush cache over queue item
* @ep_num: Endpoint number
*
* This function flushes cache over qTD pair for particular endpoint.
*/
static void ci_flush_qtd(int ep_num)
{
struct ept_queue_item *item = ci_get_qtd(ep_num, 0);
const uint32_t start = (uint32_t)item;
const uint32_t end_raw = start + 2 * sizeof(*item);
const uint32_t end = roundup(end_raw, ARCH_DMA_MINALIGN);
flush_dcache_range(start, end);
}
/**
* ci_invalidate_qtd - invalidate cache over queue item
* @ep_num: Endpoint number
*
* This function invalidates cache over qTD pair for particular endpoint.
*/
static void ci_invalidate_qtd(int ep_num)
{
struct ept_queue_item *item = ci_get_qtd(ep_num, 0);
const uint32_t start = (uint32_t)item;
const uint32_t end_raw = start + 2 * sizeof(*item);
const uint32_t end = roundup(end_raw, ARCH_DMA_MINALIGN);
invalidate_dcache_range(start, end);
}
static struct usb_request *
ci_ep_alloc_request(struct usb_ep *ep, unsigned int gfp_flags)
{
struct ci_ep *ci_ep = container_of(ep, struct ci_ep, ep);
return &ci_ep->req;
}
static void ci_ep_free_request(struct usb_ep *ep, struct usb_request *_req)
{
return;
}
static void ep_enable(int num, int in, int maxpacket)
{
struct ci_udc *udc = (struct ci_udc *)controller.ctrl->hcor;
unsigned n;
n = readl(&udc->epctrl[num]);
if (in)
n |= (CTRL_TXE | CTRL_TXR | CTRL_TXT_BULK);
else
n |= (CTRL_RXE | CTRL_RXR | CTRL_RXT_BULK);
if (num != 0) {
struct ept_queue_head *head = ci_get_qh(num, in);
head->config = CONFIG_MAX_PKT(maxpacket) | CONFIG_ZLT;
ci_flush_qh(num);
}
writel(n, &udc->epctrl[num]);
}
static int ci_ep_enable(struct usb_ep *ep,
const struct usb_endpoint_descriptor *desc)
{
struct ci_ep *ci_ep = container_of(ep, struct ci_ep, ep);
int num, in;
num = desc->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK;
in = (desc->bEndpointAddress & USB_DIR_IN) != 0;
ci_ep->desc = desc;
if (num) {
int max = get_unaligned_le16(&desc->wMaxPacketSize);
if ((max > 64) && (controller.gadget.speed == USB_SPEED_FULL))
max = 64;
if (ep->maxpacket != max) {
DBG("%s: from %d to %d\n", __func__,
ep->maxpacket, max);
ep->maxpacket = max;
}
}
ep_enable(num, in, ep->maxpacket);
DBG("%s: num=%d maxpacket=%d\n", __func__, num, ep->maxpacket);
return 0;
}
static int ci_ep_disable(struct usb_ep *ep)
{
struct ci_ep *ci_ep = container_of(ep, struct ci_ep, ep);
ci_ep->desc = NULL;
return 0;
}
static int ci_bounce(struct ci_ep *ep, int in)
{
uint32_t addr = (uint32_t)ep->req.buf;
uint32_t ba;
/* Input buffer address is not aligned. */
if (addr & (ARCH_DMA_MINALIGN - 1))
goto align;
/* Input buffer length is not aligned. */
if (ep->req.length & (ARCH_DMA_MINALIGN - 1))
goto align;
/* The buffer is well aligned, only flush cache. */
ep->b_len = ep->req.length;
ep->b_buf = ep->req.buf;
goto flush;
align:
/* Use internal buffer for small payloads. */
if (ep->req.length <= 64) {
ep->b_len = 64;
ep->b_buf = ep->b_fast;
} else {
ep->b_len = roundup(ep->req.length, ARCH_DMA_MINALIGN);
ep->b_buf = memalign(ARCH_DMA_MINALIGN, ep->b_len);
if (!ep->b_buf)
return -ENOMEM;
}
if (in)
memcpy(ep->b_buf, ep->req.buf, ep->req.length);
flush:
ba = (uint32_t)ep->b_buf;
flush_dcache_range(ba, ba + ep->b_len);
return 0;
}
static void ci_debounce(struct ci_ep *ep, int in)
{
uint32_t addr = (uint32_t)ep->req.buf;
uint32_t ba = (uint32_t)ep->b_buf;
if (in) {
if (addr == ba)
return; /* not a bounce */
goto free;
}
invalidate_dcache_range(ba, ba + ep->b_len);
if (addr == ba)
return; /* not a bounce */
memcpy(ep->req.buf, ep->b_buf, ep->req.actual);
free:
/* Large payloads use allocated buffer, free it. */
if (ep->b_buf != ep->b_fast)
free(ep->b_buf);
}
static int ci_ep_queue(struct usb_ep *ep,
struct usb_request *req, gfp_t gfp_flags)
{
struct ci_ep *ci_ep = container_of(ep, struct ci_ep, ep);
struct ci_udc *udc = (struct ci_udc *)controller.ctrl->hcor;
struct ept_queue_item *item;
struct ept_queue_head *head;
int bit, num, len, in, ret;
num = ci_ep->desc->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK;
in = (ci_ep->desc->bEndpointAddress & USB_DIR_IN) != 0;
item = ci_get_qtd(num, in);
head = ci_get_qh(num, in);
len = req->length;
ret = ci_bounce(ci_ep, in);
if (ret)
return ret;
item->next = TERMINATE;
item->info = INFO_BYTES(len) | INFO_IOC | INFO_ACTIVE;
item->page0 = (uint32_t)ci_ep->b_buf;
item->page1 = ((uint32_t)ci_ep->b_buf & 0xfffff000) + 0x1000;
item->page2 = ((uint32_t)ci_ep->b_buf & 0xfffff000) + 0x2000;
item->page3 = ((uint32_t)ci_ep->b_buf & 0xfffff000) + 0x3000;
item->page4 = ((uint32_t)ci_ep->b_buf & 0xfffff000) + 0x4000;
ci_flush_qtd(num);
head->next = (unsigned) item;
head->info = 0;
DBG("ept%d %s queue len %x, buffer %p\n",
num, in ? "in" : "out", len, ci_ep->b_buf);
ci_flush_qh(num);
if (in)
bit = EPT_TX(num);
else
bit = EPT_RX(num);
writel(bit, &udc->epprime);
return 0;
}
static void handle_ep_complete(struct ci_ep *ep)
{
struct ept_queue_item *item;
int num, in, len;
num = ep->desc->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK;
in = (ep->desc->bEndpointAddress & USB_DIR_IN) != 0;
if (num == 0)
ep->desc = &ep0_out_desc;
item = ci_get_qtd(num, in);
ci_invalidate_qtd(num);
if (item->info & 0xff)
printf("EP%d/%s FAIL info=%x pg0=%x\n",
num, in ? "in" : "out", item->info, item->page0);
len = (item->info >> 16) & 0x7fff;
ep->req.actual = ep->req.length - len;
ci_debounce(ep, in);
DBG("ept%d %s complete %x\n",
num, in ? "in" : "out", len);
ep->req.complete(&ep->ep, &ep->req);
if (num == 0) {
ep->req.length = 0;
usb_ep_queue(&ep->ep, &ep->req, 0);
ep->desc = &ep0_in_desc;
}
}
#define SETUP(type, request) (((type) << 8) | (request))
static void handle_setup(void)
{
struct usb_request *req = &controller.ep[0].req;
struct ci_udc *udc = (struct ci_udc *)controller.ctrl->hcor;
struct ept_queue_head *head;
struct usb_ctrlrequest r;
int status = 0;
int num, in, _num, _in, i;
char *buf;
head = ci_get_qh(0, 0); /* EP0 OUT */
ci_invalidate_qh(0);
memcpy(&r, head->setup_data, sizeof(struct usb_ctrlrequest));
writel(EPT_RX(0), &udc->epstat);
DBG("handle setup %s, %x, %x index %x value %x\n", reqname(r.bRequest),
r.bRequestType, r.bRequest, r.wIndex, r.wValue);
switch (SETUP(r.bRequestType, r.bRequest)) {
case SETUP(USB_RECIP_ENDPOINT, USB_REQ_CLEAR_FEATURE):
_num = r.wIndex & 15;
_in = !!(r.wIndex & 0x80);
if ((r.wValue == 0) && (r.wLength == 0)) {
req->length = 0;
for (i = 0; i < NUM_ENDPOINTS; i++) {
struct ci_ep *ep = &controller.ep[i];
if (!ep->desc)
continue;
num = ep->desc->bEndpointAddress
& USB_ENDPOINT_NUMBER_MASK;
in = (ep->desc->bEndpointAddress
& USB_DIR_IN) != 0;
if ((num == _num) && (in == _in)) {
ep_enable(num, in, ep->ep.maxpacket);
usb_ep_queue(controller.gadget.ep0,
req, 0);
break;
}
}
}
return;
case SETUP(USB_RECIP_DEVICE, USB_REQ_SET_ADDRESS):
/*
* write address delayed (will take effect
* after the next IN txn)
*/
writel((r.wValue << 25) | (1 << 24), &udc->devaddr);
req->length = 0;
usb_ep_queue(controller.gadget.ep0, req, 0);
return;
case SETUP(USB_DIR_IN | USB_RECIP_DEVICE, USB_REQ_GET_STATUS):
req->length = 2;
buf = (char *)req->buf;
buf[0] = 1 << USB_DEVICE_SELF_POWERED;
buf[1] = 0;
usb_ep_queue(controller.gadget.ep0, req, 0);
return;
}
/* pass request up to the gadget driver */
if (controller.driver)
status = controller.driver->setup(&controller.gadget, &r);
else
status = -ENODEV;
if (!status)
return;
DBG("STALL reqname %s type %x value %x, index %x\n",
reqname(r.bRequest), r.bRequestType, r.wValue, r.wIndex);
writel((1<<16) | (1 << 0), &udc->epctrl[0]);
}
static void stop_activity(void)
{
int i, num, in;
struct ept_queue_head *head;
struct ci_udc *udc = (struct ci_udc *)controller.ctrl->hcor;
writel(readl(&udc->epcomp), &udc->epcomp);
writel(readl(&udc->epstat), &udc->epstat);
writel(0xffffffff, &udc->epflush);
/* error out any pending reqs */
for (i = 0; i < NUM_ENDPOINTS; i++) {
if (i != 0)
writel(0, &udc->epctrl[i]);
if (controller.ep[i].desc) {
num = controller.ep[i].desc->bEndpointAddress
& USB_ENDPOINT_NUMBER_MASK;
in = (controller.ep[i].desc->bEndpointAddress
& USB_DIR_IN) != 0;
head = ci_get_qh(num, in);
head->info = INFO_ACTIVE;
ci_flush_qh(num);
}
}
}
void udc_irq(void)
{
struct ci_udc *udc = (struct ci_udc *)controller.ctrl->hcor;
unsigned n = readl(&udc->usbsts);
writel(n, &udc->usbsts);
int bit, i, num, in;
n &= (STS_SLI | STS_URI | STS_PCI | STS_UI | STS_UEI);
if (n == 0)
return;
if (n & STS_URI) {
DBG("-- reset --\n");
stop_activity();
}
if (n & STS_SLI)
DBG("-- suspend --\n");
if (n & STS_PCI) {
int max = 64;
int speed = USB_SPEED_FULL;
bit = (readl(&udc->portsc) >> 26) & 3;
DBG("-- portchange %x %s\n", bit, (bit == 2) ? "High" : "Full");
if (bit == 2) {
speed = USB_SPEED_HIGH;
max = 512;
}
controller.gadget.speed = speed;
for (i = 1; i < NUM_ENDPOINTS; i++) {
if (controller.ep[i].ep.maxpacket > max)
controller.ep[i].ep.maxpacket = max;
}
}
if (n & STS_UEI)
printf("<UEI %x>\n", readl(&udc->epcomp));
if ((n & STS_UI) || (n & STS_UEI)) {
n = readl(&udc->epstat);
if (n & EPT_RX(0))
handle_setup();
n = readl(&udc->epcomp);
if (n != 0)
writel(n, &udc->epcomp);
for (i = 0; i < NUM_ENDPOINTS && n; i++) {
if (controller.ep[i].desc) {
num = controller.ep[i].desc->bEndpointAddress
& USB_ENDPOINT_NUMBER_MASK;
in = (controller.ep[i].desc->bEndpointAddress
& USB_DIR_IN) != 0;
bit = (in) ? EPT_TX(num) : EPT_RX(num);
if (n & bit)
handle_ep_complete(&controller.ep[i]);
}
}
}
}
int usb_gadget_handle_interrupts(void)
{
u32 value;
struct ci_udc *udc = (struct ci_udc *)controller.ctrl->hcor;
value = readl(&udc->usbsts);
if (value)
udc_irq();
return value;
}
static int ci_pullup(struct usb_gadget *gadget, int is_on)
{
struct ci_udc *udc = (struct ci_udc *)controller.ctrl->hcor;
if (is_on) {
/* RESET */
writel(USBCMD_ITC(MICRO_8FRAME) | USBCMD_RST, &udc->usbcmd);
udelay(200);
writel((unsigned)controller.epts, &udc->epinitaddr);
/* select DEVICE mode */
writel(USBMODE_DEVICE, &udc->usbmode);
writel(0xffffffff, &udc->epflush);
/* Turn on the USB connection by enabling the pullup resistor */
writel(USBCMD_ITC(MICRO_8FRAME) | USBCMD_RUN, &udc->usbcmd);
} else {
stop_activity();
writel(USBCMD_FS2, &udc->usbcmd);
udelay(800);
if (controller.driver)
controller.driver->disconnect(gadget);
}
return 0;
}
void udc_disconnect(void)
{
struct ci_udc *udc = (struct ci_udc *)controller.ctrl->hcor;
/* disable pullup */
stop_activity();
writel(USBCMD_FS2, &udc->usbcmd);
udelay(800);
if (controller.driver)
controller.driver->disconnect(&controller.gadget);
}
static int ci_udc_probe(void)
{
struct ept_queue_head *head;
uint8_t *imem;
int i;
const int num = 2 * NUM_ENDPOINTS;
const int eplist_min_align = 4096;
const int eplist_align = roundup(eplist_min_align, ARCH_DMA_MINALIGN);
const int eplist_raw_sz = num * sizeof(struct ept_queue_head);
const int eplist_sz = roundup(eplist_raw_sz, ARCH_DMA_MINALIGN);
const int ilist_align = roundup(ARCH_DMA_MINALIGN, 32);
const int ilist_ent_raw_sz = 2 * sizeof(struct ept_queue_item);
const int ilist_ent_sz = roundup(ilist_ent_raw_sz, ARCH_DMA_MINALIGN);
const int ilist_sz = NUM_ENDPOINTS * ilist_ent_sz;
/* The QH list must be aligned to 4096 bytes. */
controller.epts = memalign(eplist_align, eplist_sz);
if (!controller.epts)
return -ENOMEM;
memset(controller.epts, 0, eplist_sz);
/*
* Each qTD item must be 32-byte aligned, each qTD touple must be
* cacheline aligned. There are two qTD items for each endpoint and
* only one of them is used for the endpoint at time, so we can group
* them together.
*/
controller.items_mem = memalign(ilist_align, ilist_sz);
if (!controller.items_mem) {
free(controller.epts);
return -ENOMEM;
}
memset(controller.items_mem, 0, ilist_sz);
for (i = 0; i < 2 * NUM_ENDPOINTS; i++) {
/*
* Configure QH for each endpoint. The structure of the QH list
* is such that each two subsequent fields, N and N+1 where N is
* even, in the QH list represent QH for one endpoint. The Nth
* entry represents OUT configuration and the N+1th entry does
* represent IN configuration of the endpoint.
*/
head = controller.epts + i;
if (i < 2)
head->config = CONFIG_MAX_PKT(EP0_MAX_PACKET_SIZE)
| CONFIG_ZLT | CONFIG_IOS;
else
head->config = CONFIG_MAX_PKT(EP_MAX_PACKET_SIZE)
| CONFIG_ZLT;
head->next = TERMINATE;
head->info = 0;
imem = controller.items_mem + ((i >> 1) * ilist_ent_sz);
if (i & 1)
imem += sizeof(struct ept_queue_item);
controller.items[i] = (struct ept_queue_item *)imem;
if (i & 1) {
ci_flush_qh(i - 1);
ci_flush_qtd(i - 1);
}
}
INIT_LIST_HEAD(&controller.gadget.ep_list);
/* Init EP 0 */
memcpy(&controller.ep[0].ep, &ci_ep_init[0], sizeof(*ci_ep_init));
controller.ep[0].desc = &ep0_in_desc;
controller.gadget.ep0 = &controller.ep[0].ep;
INIT_LIST_HEAD(&controller.gadget.ep0->ep_list);
/* Init EP 1..n */
for (i = 1; i < NUM_ENDPOINTS; i++) {
memcpy(&controller.ep[i].ep, &ci_ep_init[1],
sizeof(*ci_ep_init));
list_add_tail(&controller.ep[i].ep.ep_list,
&controller.gadget.ep_list);
}
return 0;
}
int usb_gadget_register_driver(struct usb_gadget_driver *driver)
{
struct ci_udc *udc;
int ret;
if (!driver)
return -EINVAL;
if (!driver->bind || !driver->setup || !driver->disconnect)
return -EINVAL;
if (driver->speed != USB_SPEED_FULL && driver->speed != USB_SPEED_HIGH)
return -EINVAL;
ret = usb_lowlevel_init(0, USB_INIT_DEVICE, (void **)&controller.ctrl);
if (ret)
return ret;
ret = ci_udc_probe();
if (!ret) {
udc = (struct ci_udc *)controller.ctrl->hcor;
/* select ULPI phy */
writel(PTS(PTS_ENABLE) | PFSC, &udc->portsc);
}
ret = driver->bind(&controller.gadget);
if (ret) {
DBG("driver->bind() returned %d\n", ret);
return ret;
}
controller.driver = driver;
return 0;
}
int usb_gadget_unregister_driver(struct usb_gadget_driver *driver)
{
return 0;
}