/**
* usb_descriptor_fillbuf - fill buffer with descriptors
* @buf: Buffer to be filled
* @buflen: Size of buf
* @src: Array of descriptor pointers, terminated by null pointer.
*
* Copies descriptors into the buffer, returning the length or a
* negative error code if they can't all be copied. Useful when
* assembling descriptors for an associated set of interfaces used
* as part of configuring a composite device; or in other cases where
* sets of descriptors need to be marshaled.
*/
int
usb_descriptor_fillbuf(void *buf, unsigned buflen,
const struct usb_descriptor_header **src)
{
u8 *dest = buf;
struct usb_interface_descriptor *interface;
struct usb_endpoint_descriptor *ep;
if (!src)
return -EINVAL;
/* fill buffer from src[] until null descriptor ptr */
for (; NULL != *src; src++) {
unsigned len = (*src)->bLength;
if (len > buflen)
return -EINVAL;
memcpy(dest, *src, len);
buflen -= len;
dest += len;
/* dump endpint descriptor to usb logger*/
switch (((*src)->bDescriptorType)) {
case USB_DT_INTERFACE:
interface = (struct usb_interface_descriptor *)*src;
USB_LOGGER(INTERFACE_DESCRIPTOR, USB_DESCRIPTOR_FILLBUF, interface->bLength, \
interface->bDescriptorType, interface->bInterfaceNumber, \
interface->bAlternateSetting, interface->bNumEndpoints,\
interface->bInterfaceClass, interface->bInterfaceSubClass, \
interface->bInterfaceProtocol, interface->iInterface);
break;
case USB_DT_ENDPOINT:
ep = (struct usb_endpoint_descriptor *)*src;
USB_LOGGER(ENDPOINT_DESCRIPTOR, USB_DESCRIPTOR_FILLBUF, ep->bLength, \
ep->bDescriptorType, ep->bEndpointAddress, \
ep->bmAttributes, ep->wMaxPacketSize, ep->bInterval);
break;
default:
USB_LOGGER(STRING, USB_DESCRIPTOR_FILLBUF, "type", (*src)->bDescriptorType);
break;
}
}
return dest - (u8 *)buf;
}
static void gs_close(struct tty_struct *tty, struct file *file)
{
struct gs_port *port = tty->driver_data;
struct gserial *gser;
spin_lock_irq(&port->port_lock);
if (port->open_count != 1) {
if (port->open_count == 0)
WARN_ON(1);
else
--port->open_count;
goto exit;
}
pr_debug("gs_close: ttyGS%d (%p,%p) ...\n", port->port_num, tty, file);
USB_LOGGER(GS_CLOSE,GS_CLOSE, port->port_num, tty, file);
/* mark port as closing but in use; we can drop port lock
* and sleep if necessary
*/
port->openclose = true;
port->open_count = 0;
gser = port->port_usb;
if (gser && gser->disconnect)
gser->disconnect(gser);
/* wait for circular write buffer to drain, disconnect, or at
* most GS_CLOSE_TIMEOUT seconds; then discard the rest
*/
if (gs_buf_data_avail(&port->port_write_buf) > 0 && gser) {
spin_unlock_irq(&port->port_lock);
wait_event_interruptible_timeout(port->drain_wait,
gs_writes_finished(port),
GS_CLOSE_TIMEOUT * HZ);
spin_lock_irq(&port->port_lock);
gser = port->port_usb;
}
/* Iff we're disconnected, there can be no I/O in flight so it's
* ok to free the circular buffer; else just scrub it. And don't
* let the push tasklet fire again until we're re-opened.
*/
if (gser == NULL)
gs_buf_free(&port->port_write_buf);
else
gs_buf_clear(&port->port_write_buf);
tty->driver_data = NULL;
port->port_tty = NULL;
port->openclose = false;
pr_debug("gs_close: ttyGS%d (%p,%p) done!\n",
port->port_num, tty, file);
wake_up_interruptible(&port->close_wait);
exit:
spin_unlock_irq(&port->port_lock);
}
/*
* gs_open sets up the link between a gs_port and its associated TTY.
* That link is broken *only* by TTY close(), and all driver methods
* know that.
*/
static int gs_open(struct tty_struct *tty, struct file *file)
{
int port_num = tty->index;
struct gs_port *port;
int status;
if (port_num < 0 || port_num >= n_ports)
return -ENXIO;
do {
mutex_lock(&ports[port_num].lock);
port = ports[port_num].port;
if (!port)
status = -ENODEV;
else {
spin_lock_irq(&port->port_lock);
/* already open? Great. */
if (port->open_count) {
status = 0;
port->open_count++;
/* currently opening/closing? wait ... */
} else if (port->openclose) {
status = -EBUSY;
/* ... else we do the work */
} else {
status = -EAGAIN;
port->openclose = true;
}
spin_unlock_irq(&port->port_lock);
}
mutex_unlock(&ports[port_num].lock);
switch (status) {
default:
/* fully handled */
return status;
case -EAGAIN:
/* must do the work */
break;
case -EBUSY:
/* wait for EAGAIN task to finish */
msleep(1);
/* REVISIT could have a waitchannel here, if
* concurrent open performance is important
*/
break;
}
} while (status != -EAGAIN);
/* Do the "real open" */
spin_lock_irq(&port->port_lock);
/* allocate circular buffer on first open */
if (port->port_write_buf.buf_buf == NULL) {
spin_unlock_irq(&port->port_lock);
status = gs_buf_alloc(&port->port_write_buf, WRITE_BUF_SIZE);
spin_lock_irq(&port->port_lock);
if (status) {
pr_debug("gs_open: ttyGS%d (%p,%p) no buffer\n",
port->port_num, tty, file);
port->openclose = false;
goto exit_unlock_port;
}
}
/* REVISIT if REMOVED (ports[].port NULL), abort the open
* to let rmmod work faster (but this way isn't wrong).
*/
/* REVISIT maybe wait for "carrier detect" */
tty->driver_data = port;
port->port_tty = tty;
port->open_count = 1;
port->openclose = false;
/* if connected, start the I/O stream */
if (port->port_usb) {
struct gserial *gser = port->port_usb;
pr_debug("gs_open: start ttyGS%d\n", port->port_num);
gs_start_io(port);
if (gser->connect)
gser->connect(gser);
}
pr_debug("gs_open: ttyGS%d (%p,%p)\n", port->port_num, tty, file);
USB_LOGGER(GS_OPEN, GS_OPEN, port->port_num, tty, file);
status = 0;
exit_unlock_port:
spin_unlock_irq(&port->port_lock);
return status;
}
/*
* RX tasklet takes data out of the RX queue and hands it up to the TTY
* layer until it refuses to take any more data (or is throttled back).
* Then it issues reads for any further data.
*
* If the RX queue becomes full enough that no usb_request is queued,
* the OUT endpoint may begin NAKing as soon as its FIFO fills up.
* So QUEUE_SIZE packets plus however many the FIFO holds (usually two)
* can be buffered before the TTY layer's buffers (currently 64 KB).
*/
static void gs_rx_push(unsigned long _port)
{
struct gs_port *port = (void *)_port;
struct tty_struct *tty;
struct list_head *queue = &port->read_queue;
bool disconnect = false;
bool do_push = false;
/* hand any queued data to the tty */
spin_lock_irq(&port->port_lock);
tty = port->port_tty;
while (!list_empty(queue)) {
struct usb_request *req;
req = list_first_entry(queue, struct usb_request, list);
/* discard data if tty was closed */
if (!tty)
goto recycle;
/* leave data queued if tty was rx throttled */
if (test_bit(TTY_THROTTLED, &tty->flags))
break;
switch (req->status) {
case -ESHUTDOWN:
disconnect = true;
pr_vdebug(PREFIX "%d: shutdown\n", port->port_num);
break;
default:
/* presumably a transient fault */
pr_warning(PREFIX "%d: unexpected RX status %d\n",
port->port_num, req->status);
/* FALLTHROUGH */
case 0:
/* normal completion */
break;
}
USB_LOGGER(GS_RX_PUSH, GS_RX_PUSH, port->port_num, req->actual, port->n_read);
#define OUTPUT_BTYE_NUM 5
{
int i,j = 0;
char* prefix[] = {"p1","p2","p3","p4","p5"};
char* suffix[] = {"s1","s2","s3","s4","s5"};
for (i = 0; i < req->actual && i < OUTPUT_BTYE_NUM; i++)
USB_LOGGER(HEX_NUM, GS_RX_PUSH, prefix[i], *((u8 *)req->buf+i));
if (req->actual >= OUTPUT_BTYE_NUM*2) {
for(i = req->actual-1, j = 1; i >= (req->actual - OUTPUT_BTYE_NUM) \
&& i >= OUTPUT_BTYE_NUM; i--,j++) {
USB_LOGGER(HEX_NUM, GS_RX_PUSH, suffix[OUTPUT_BTYE_NUM-j], \
*((u8 *)req->buf+i));
}
}
}
/* push data to (open) tty */
if (req->actual) {
char *packet = req->buf;
unsigned size = req->actual;
unsigned n;
int count;
/* we may have pushed part of this packet already... */
n = port->n_read;
if (n) {
packet += n;
size -= n;
}
count = tty_insert_flip_string(tty, packet, size);
if (count)
do_push = true;
if (count != size) {
/* stop pushing; TTY layer can't handle more */
port->n_read += count;
pr_vdebug(PREFIX "%d: rx block %d/%d\n",
port->port_num,
count, req->actual);
break;
}
port->n_read = 0;
}
recycle:
list_move(&req->list, &port->read_pool);
port->read_started--;
}
/* Push from tty to ldisc; without low_latency set this is handled by
* a workqueue, so we won't get callbacks and can hold port_lock
*/
if (tty && do_push) {
tty_flip_buffer_push(tty);
}
/* We want our data queue to become empty ASAP, keeping data
* in the tty and ldisc (not here). If we couldn't push any
* this time around, there may be trouble unless there's an
* implicit tty_unthrottle() call on its way...
*
* REVISIT we should probably add a timer to keep the tasklet
* from starving ... but it's not clear that case ever happens.
*/
if (!list_empty(queue) && tty) {
if (!test_bit(TTY_THROTTLED, &tty->flags)) {
if (do_push)
tasklet_schedule(&port->push);
else
pr_warning(PREFIX "%d: RX not scheduled?\n",
port->port_num);
}
}
/* If we're still connected, refill the USB RX queue. */
if (!disconnect && port->port_usb)
gs_start_rx(port);
spin_unlock_irq(&port->port_lock);
}
/*
* gs_start_tx
*
* This function finds available write requests, calls
* gs_send_packet to fill these packets with data, and
* continues until either there are no more write requests
* available or no more data to send. This function is
* run whenever data arrives or write requests are available.
*
* Context: caller owns port_lock; port_usb is non-null.
*/
static int gs_start_tx(struct gs_port *port)
/*
__releases(&port->port_lock)
__acquires(&port->port_lock)
*/
{
struct list_head *pool = &port->write_pool;
//struct usb_ep *in = port->port_usb->in;
struct usb_ep *in;
int status = 0;
bool do_tty_wake = false;
if (!port->port_usb) /* abort immediately after disconnect */
return -EINVAL;
in = port->port_usb->in;
while (!list_empty(pool)) {
struct usb_request *req;
int len;
if (port->write_started >= QUEUE_SIZE)
break;
req = list_entry(pool->next, struct usb_request, list);
len = gs_send_packet(port, req->buf, in->maxpacket);
if (len == 0) {
wake_up_interruptible(&port->drain_wait);
break;
}
do_tty_wake = true;
req->length = len;
list_del(&req->list);
req->zero = (gs_buf_data_avail(&port->port_write_buf) == 0);
pr_vdebug(PREFIX "%d: tx len=%d, 0x%02x 0x%02x 0x%02x ...\n",
port->port_num, len, *((u8 *)req->buf),
*((u8 *)req->buf+1), *((u8 *)req->buf+2));
USB_LOGGER(GS_START_TX, GS_START_TX, port->port_num, len);
#define OUTPUT_BTYE_NUM 5
{
int i,j = 0;
char* prefix[] = {"p1","p2","p3","p4","p5"};
char* suffix[] = {"s1","s2","s3","s4","s5"};
for (i = 0; i < req->actual && i < OUTPUT_BTYE_NUM; i++)
USB_LOGGER(HEX_NUM, GS_START_TX, prefix[i], *((u8 *)req->buf+i));
if (req->actual >= OUTPUT_BTYE_NUM*2) {
for(i = req->actual-1, j = 1; i >= (req->actual - OUTPUT_BTYE_NUM) \
&& i >= OUTPUT_BTYE_NUM; i--,j++) {
USB_LOGGER(HEX_NUM, GS_START_TX, suffix[OUTPUT_BTYE_NUM-j], \
*((u8 *)req->buf+i));
}
}
}
/* Drop lock while we call out of driver; completions
* could be issued while we do so. Disconnection may
* happen too; maybe immediately before we queue this!
*
* NOTE that we may keep sending data for a while after
* the TTY closed (dev->ioport->port_tty is NULL).
*/
spin_unlock(&port->port_lock);
status = usb_ep_queue(in, req, GFP_ATOMIC);
spin_lock(&port->port_lock);
if (status) {
pr_debug("%s: %s %s err %d\n",
__func__, "queue", in->name, status);
list_add(&req->list, pool);
break;
}
port->write_started++;
/* abort immediately after disconnect */
if (!port->port_usb)
break;
}
if (do_tty_wake && port->port_tty)
tty_wakeup(port->port_tty);
return status;
}
