// SPDX-License-Identifier: GPL-2.0/* * USB Serial Converter Generic functions * * Copyright (C) 2010 - 2013 Johan Hovold (jhovold@gmail.com) * Copyright (C) 1999 - 2002 Greg Kroah-Hartman (greg@kroah.com) */ #include <linux/kernel.h>#include <linux/sched/signal.h>#include <linux/errno.h>#include <linux/slab.h>#include <linux/sysrq.h>#include <linux/tty.h>#include <linux/tty_flip.h>#include <linux/module.h>#include <linux/moduleparam.h>#include <linux/usb.h>#include <linux/usb/serial.h>#include <linux/kfifo.h>#include <linux/serial.h> #ifdef CONFIG_USB_SERIAL_GENERIC static __u16 vendor = 0x05f9;static __u16 product = 0xffff; module_param(vendor, ushort, 0);MODULE_PARM_DESC(vendor, "User specified USB idVendor"); module_param(product, ushort, 0);MODULE_PARM_DESC(product, "User specified USB idProduct"); static struct usb_device_id generic_device_ids[2]; /* Initially all zeroes. */ static int usb_serial_generic_probe(struct usb_serial *serial, const struct usb_device_id *id){ struct device *dev = &serial->interface->dev; dev_info(dev, "The \"generic\" usb-serial driver is only for testing and one-off prototypes.\n"); dev_info(dev, "Tell linux-usb@vger.kernel.org to add your device to a proper driver.\n"); return 0;} static int usb_serial_generic_calc_num_ports(struct usb_serial *serial, struct usb_serial_endpoints *epds){ struct device *dev = &serial->interface->dev; int num_ports; num_ports = max(epds->num_bulk_in, epds->num_bulk_out); if (num_ports == 0) { dev_err(dev, "device has no bulk endpoints\n"); return -ENODEV; } return num_ports;} static struct usb_serial_driver usb_serial_generic_device = { .driver = { .name = "generic", }, .id_table = generic_device_ids, .probe = usb_serial_generic_probe, .calc_num_ports = usb_serial_generic_calc_num_ports, .throttle = usb_serial_generic_throttle, .unthrottle = usb_serial_generic_unthrottle, .resume = usb_serial_generic_resume,}; static struct usb_serial_driver * const serial_drivers[] = { &usb_serial_generic_device, NULL}; #endif int usb_serial_generic_register(void){ int retval = 0; #ifdef CONFIG_USB_SERIAL_GENERIC generic_device_ids[0].idVendor = vendor; generic_device_ids[0].idProduct = product; generic_device_ids[0].match_flags = USB_DEVICE_ID_MATCH_VENDOR | USB_DEVICE_ID_MATCH_PRODUCT; retval = usb_serial_register_drivers(serial_drivers, "usbserial_generic", generic_device_ids);#endif return retval;} void usb_serial_generic_deregister(void){#ifdef CONFIG_USB_SERIAL_GENERIC usb_serial_deregister_drivers(serial_drivers);#endif} int usb_serial_generic_open(struct tty_struct *tty, struct usb_serial_port *port){ int result = 0; clear_bit(USB_SERIAL_THROTTLED, &port->flags); if (port->bulk_in_size) result = usb_serial_generic_submit_read_urbs(port, GFP_KERNEL); return result;}EXPORT_SYMBOL_GPL(usb_serial_generic_open); void usb_serial_generic_close(struct usb_serial_port *port){ unsigned long flags; int i; if (port->bulk_out_size) { for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i) usb_kill_urb(port->write_urbs[i]); spin_lock_irqsave(&port->lock, flags); kfifo_reset_out(&port->write_fifo); spin_unlock_irqrestore(&port->lock, flags); } if (port->bulk_in_size) { for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i) usb_kill_urb(port->read_urbs[i]); }}EXPORT_SYMBOL_GPL(usb_serial_generic_close); int usb_serial_generic_prepare_write_buffer(struct usb_serial_port *port, void *dest, size_t size){ return kfifo_out_locked(&port->write_fifo, dest, size, &port->lock);} /** * usb_serial_generic_write_start - start writing buffered data * @port: usb-serial port * @mem_flags: flags to use for memory allocations * * Serialised using USB_SERIAL_WRITE_BUSY flag. * * Return: Zero on success or if busy, otherwise a negative errno value. */int usb_serial_generic_write_start(struct usb_serial_port *port, gfp_t mem_flags){ struct urb *urb; int count, result; unsigned long flags; int i; if (test_and_set_bit_lock(USB_SERIAL_WRITE_BUSY, &port->flags)) return 0;retry: spin_lock_irqsave(&port->lock, flags); if (!port->write_urbs_free || !kfifo_len(&port->write_fifo)) { clear_bit_unlock(USB_SERIAL_WRITE_BUSY, &port->flags); spin_unlock_irqrestore(&port->lock, flags); return 0; } i = (int)find_first_bit(&port->write_urbs_free, ARRAY_SIZE(port->write_urbs)); spin_unlock_irqrestore(&port->lock, flags); urb = port->write_urbs[i]; count = port->serial->type->prepare_write_buffer(port, urb->transfer_buffer, port->bulk_out_size); urb->transfer_buffer_length = count; usb_serial_debug_data(&port->dev, __func__, count, urb->transfer_buffer); spin_lock_irqsave(&port->lock, flags); port->tx_bytes += count; spin_unlock_irqrestore(&port->lock, flags); clear_bit(i, &port->write_urbs_free); result = usb_submit_urb(urb, mem_flags); if (result) { dev_err_console(port, "%s - error submitting urb: %d\n", __func__, result); set_bit(i, &port->write_urbs_free); spin_lock_irqsave(&port->lock, flags); port->tx_bytes -= count; spin_unlock_irqrestore(&port->lock, flags); clear_bit_unlock(USB_SERIAL_WRITE_BUSY, &port->flags); return result; } goto retry; /* try sending off another urb */}EXPORT_SYMBOL_GPL(usb_serial_generic_write_start); /** * usb_serial_generic_write - generic write function * @tty: tty for the port * @port: usb-serial port * @buf: data to write * @count: number of bytes to write * * Return: The number of characters buffered, which may be anything from * zero to @count, or a negative errno value. */int usb_serial_generic_write(struct tty_struct *tty, struct usb_serial_port *port, const unsigned char *buf, int count){ int result; if (!port->bulk_out_size) return -ENODEV; if (!count) return 0; count = kfifo_in_locked(&port->write_fifo, buf, count, &port->lock); result = usb_serial_generic_write_start(port, GFP_ATOMIC); if (result) return result; return count;}EXPORT_SYMBOL_GPL(usb_serial_generic_write); unsigned int usb_serial_generic_write_room(struct tty_struct *tty){ struct usb_serial_port *port = tty->driver_data; unsigned long flags; unsigned int room; if (!port->bulk_out_size) return 0; spin_lock_irqsave(&port->lock, flags); room = kfifo_avail(&port->write_fifo); spin_unlock_irqrestore(&port->lock, flags); dev_dbg(&port->dev, "%s - returns %u\n", __func__, room); return room;} unsigned int usb_serial_generic_chars_in_buffer(struct tty_struct *tty){ struct usb_serial_port *port = tty->driver_data; unsigned long flags; unsigned int chars; if (!port->bulk_out_size) return 0; spin_lock_irqsave(&port->lock, flags); chars = kfifo_len(&port->write_fifo) + port->tx_bytes; spin_unlock_irqrestore(&port->lock, flags); dev_dbg(&port->dev, "%s - returns %u\n", __func__, chars); return chars;}EXPORT_SYMBOL_GPL(usb_serial_generic_chars_in_buffer); void usb_serial_generic_wait_until_sent(struct tty_struct *tty, long timeout){ struct usb_serial_port *port = tty->driver_data; unsigned int bps; unsigned long period; unsigned long expire; bps = tty_get_baud_rate(tty); if (!bps) bps = 9600; /* B0 */ /* * Use a poll-period of roughly the time it takes to send one * character or at least one jiffy. */ period = max_t(unsigned long, (10 * HZ / bps), 1); if (timeout) period = min_t(unsigned long, period, timeout); dev_dbg(&port->dev, "%s - timeout = %u ms, period = %u ms\n", __func__, jiffies_to_msecs(timeout), jiffies_to_msecs(period)); expire = jiffies + timeout; while (!port->serial->type->tx_empty(port)) { schedule_timeout_interruptible(period); if (signal_pending(current)) break; if (timeout && time_after(jiffies, expire)) break; }}EXPORT_SYMBOL_GPL(usb_serial_generic_wait_until_sent); static int usb_serial_generic_submit_read_urb(struct usb_serial_port *port, int index, gfp_t mem_flags){ int res; if (!test_and_clear_bit(index, &port->read_urbs_free)) return 0; dev_dbg(&port->dev, "%s - urb %d\n", __func__, index); res = usb_submit_urb(port->read_urbs[index], mem_flags); if (res) { if (res != -EPERM && res != -ENODEV) { dev_err(&port->dev, "%s - usb_submit_urb failed: %d\n", __func__, res); } set_bit(index, &port->read_urbs_free); return res; } return 0;} int usb_serial_generic_submit_read_urbs(struct usb_serial_port *port, gfp_t mem_flags){ int res; int i; for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i) { res = usb_serial_generic_submit_read_urb(port, i, mem_flags); if (res) goto err; } return 0;err: for (; i >= 0; --i) usb_kill_urb(port->read_urbs[i]); return res;}EXPORT_SYMBOL_GPL(usb_serial_generic_submit_read_urbs); void usb_serial_generic_process_read_urb(struct urb *urb){ struct usb_serial_port *port = urb->context; char *ch = urb->transfer_buffer; int i; if (!urb->actual_length) return; /* * The per character mucking around with sysrq path it too slow for * stuff like 3G modems, so shortcircuit it in the 99.9999999% of * cases where the USB serial is not a console anyway. */ if (port->sysrq) { for (i = 0; i < urb->actual_length; i++, ch++) { if (!usb_serial_handle_sysrq_char(port, *ch)) tty_insert_flip_char(&port->port, *ch, TTY_NORMAL); } } else { tty_insert_flip_string(&port->port, ch, urb->actual_length); } tty_flip_buffer_push(&port->port);}EXPORT_SYMBOL_GPL(usb_serial_generic_process_read_urb); void usb_serial_generic_read_bulk_callback(struct urb *urb){ struct usb_serial_port *port = urb->context; unsigned char *data = urb->transfer_buffer; bool stopped = false; int status = urb->status; int i; for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i) { if (urb == port->read_urbs[i]) break; } dev_dbg(&port->dev, "%s - urb %d, len %d\n", __func__, i, urb->actual_length); switch (status) { case 0: usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data); port->serial->type->process_read_urb(urb); break; case -ENOENT: case -ECONNRESET: case -ESHUTDOWN: dev_dbg(&port->dev, "%s - urb stopped: %d\n", __func__, status); stopped = true; break; case -EPIPE: dev_err(&port->dev, "%s - urb stopped: %d\n", __func__, status); stopped = true; break; default: dev_dbg(&port->dev, "%s - nonzero urb status: %d\n", __func__, status); break; } /* * Make sure URB processing is done before marking as free to avoid * racing with unthrottle() on another CPU. Matches the barriers * implied by the test_and_clear_bit() in * usb_serial_generic_submit_read_urb(). */ smp_mb__before_atomic(); set_bit(i, &port->read_urbs_free); /* * Make sure URB is marked as free before checking the throttled flag * to avoid racing with unthrottle() on another CPU. Matches the * smp_mb__after_atomic() in unthrottle(). */ smp_mb__after_atomic(); if (stopped) return; if (test_bit(USB_SERIAL_THROTTLED, &port->flags)) return; usb_serial_generic_submit_read_urb(port, i, GFP_ATOMIC);}EXPORT_SYMBOL_GPL(usb_serial_generic_read_bulk_callback); void usb_serial_generic_write_bulk_callback(struct urb *urb){ unsigned long flags; struct usb_serial_port *port = urb->context; int status = urb->status; int i; for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i) { if (port->write_urbs[i] == urb) break; } spin_lock_irqsave(&port->lock, flags); port->tx_bytes -= urb->transfer_buffer_length; set_bit(i, &port->write_urbs_free); spin_unlock_irqrestore(&port->lock, flags); switch (status) { case 0: break; case -ENOENT: case -ECONNRESET: case -ESHUTDOWN: dev_dbg(&port->dev, "%s - urb stopped: %d\n", __func__, status); return; case -EPIPE: dev_err_console(port, "%s - urb stopped: %d\n", __func__, status); return; default: dev_err_console(port, "%s - nonzero urb status: %d\n", __func__, status); break; } usb_serial_generic_write_start(port, GFP_ATOMIC); usb_serial_port_softint(port);}EXPORT_SYMBOL_GPL(usb_serial_generic_write_bulk_callback); void usb_serial_generic_throttle(struct tty_struct *tty){ struct usb_serial_port *port = tty->driver_data; set_bit(USB_SERIAL_THROTTLED, &port->flags);}EXPORT_SYMBOL_GPL(usb_serial_generic_throttle); void usb_serial_generic_unthrottle(struct tty_struct *tty){ struct usb_serial_port *port = tty->driver_data; clear_bit(USB_SERIAL_THROTTLED, &port->flags); /* * Matches the smp_mb__after_atomic() in * usb_serial_generic_read_bulk_callback(). */ smp_mb__after_atomic(); usb_serial_generic_submit_read_urbs(port, GFP_KERNEL);}EXPORT_SYMBOL_GPL(usb_serial_generic_unthrottle); static bool usb_serial_generic_msr_changed(struct tty_struct *tty, unsigned long arg, struct async_icount *cprev){ struct usb_serial_port *port = tty->driver_data; struct async_icount cnow;Lines 1–500 of 656. Load more
// SPDX-License-Identifier: GPL-2.0 /* * USB Serial Converter Generic functions * * Copyright (C) 2010 - 2013 Johan Hovold (jhovold@gmail.com) * Copyright (C) 1999 - 2002 Greg Kroah-Hartman (greg@kroah.com) */ #include <linux/kernel.h> #include <linux/sched/signal.h> #include <linux/errno.h> #include <linux/slab.h> #include <linux/sysrq.h> #include <linux/tty.h> #include <linux/tty_flip.h> #include <linux/module.h> #include <linux/moduleparam.h> #include <linux/usb.h> #include <linux/usb/serial.h> #include <linux/kfifo.h> #include <linux/serial.h> #ifdef CONFIG_USB_SERIAL_GENERIC static __u16 vendor = 0x05f9; static __u16 product = 0xffff; module_param(vendor, ushort, 0); MODULE_PARM_DESC(vendor, "User specified USB idVendor"); module_param(product, ushort, 0); MODULE_PARM_DESC(product, "User specified USB idProduct"); static struct usb_device_id generic_device_ids[2]; /* Initially all zeroes. */ static int usb_serial_generic_probe(struct usb_serial *serial, const struct usb_device_id *id) { struct device *dev = &serial->interface->dev; dev_info(dev, "The \"generic\" usb-serial driver is only for testing and one-off prototypes.\n"); dev_info(dev, "Tell linux-usb@vger.kernel.org to add your device to a proper driver.\n"); return 0; } static int usb_serial_generic_calc_num_ports(struct usb_serial *serial, struct usb_serial_endpoints *epds) { struct device *dev = &serial->interface->dev; int num_ports; num_ports = max(epds->num_bulk_in, epds->num_bulk_out); if (num_ports == 0) { dev_err(dev, "device has no bulk endpoints\n"); return -ENODEV; } return num_ports; } static struct usb_serial_driver usb_serial_generic_device = { .driver = { .name = "generic", }, .id_table = generic_device_ids, .probe = usb_serial_generic_probe, .calc_num_ports = usb_serial_generic_calc_num_ports, .throttle = usb_serial_generic_throttle, .unthrottle = usb_serial_generic_unthrottle, .resume = usb_serial_generic_resume, }; static struct usb_serial_driver * const serial_drivers[] = { &usb_serial_generic_device, NULL }; #endif int usb_serial_generic_register(void) { int retval = 0; #ifdef CONFIG_USB_SERIAL_GENERIC generic_device_ids[0].idVendor = vendor; generic_device_ids[0].idProduct = product; generic_device_ids[0].match_flags = USB_DEVICE_ID_MATCH_VENDOR | USB_DEVICE_ID_MATCH_PRODUCT; retval = usb_serial_register_drivers(serial_drivers, "usbserial_generic", generic_device_ids); #endif return retval; } void usb_serial_generic_deregister(void) { #ifdef CONFIG_USB_SERIAL_GENERIC usb_serial_deregister_drivers(serial_drivers); #endif } int usb_serial_generic_open(struct tty_struct *tty, struct usb_serial_port *port) { int result = 0; clear_bit(USB_SERIAL_THROTTLED, &port->flags); if (port->bulk_in_size) result = usb_serial_generic_submit_read_urbs(port, GFP_KERNEL); return result; } EXPORT_SYMBOL_GPL(usb_serial_generic_open); void usb_serial_generic_close(struct usb_serial_port *port) { unsigned long flags; int i; if (port->bulk_out_size) { for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i) usb_kill_urb(port->write_urbs[i]); spin_lock_irqsave(&port->lock, flags); kfifo_reset_out(&port->write_fifo); spin_unlock_irqrestore(&port->lock, flags); } if (port->bulk_in_size) { for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i) usb_kill_urb(port->read_urbs[i]); } } EXPORT_SYMBOL_GPL(usb_serial_generic_close); int usb_serial_generic_prepare_write_buffer(struct usb_serial_port *port, void *dest, size_t size) { return kfifo_out_locked(&port->write_fifo, dest, size, &port->lock); } /** * usb_serial_generic_write_start - start writing buffered data * @port: usb-serial port * @mem_flags: flags to use for memory allocations * * Serialised using USB_SERIAL_WRITE_BUSY flag. * * Return: Zero on success or if busy, otherwise a negative errno value. */ int usb_serial_generic_write_start(struct usb_serial_port *port, gfp_t mem_flags) { struct urb *urb; int count, result; unsigned long flags; int i; if (test_and_set_bit_lock(USB_SERIAL_WRITE_BUSY, &port->flags)) return 0; retry: spin_lock_irqsave(&port->lock, flags); if (!port->write_urbs_free || !kfifo_len(&port->write_fifo)) { clear_bit_unlock(USB_SERIAL_WRITE_BUSY, &port->flags); spin_unlock_irqrestore(&port->lock, flags); return 0; } i = (int)find_first_bit(&port->write_urbs_free, ARRAY_SIZE(port->write_urbs)); spin_unlock_irqrestore(&port->lock, flags); urb = port->write_urbs[i]; count = port->serial->type->prepare_write_buffer(port, urb->transfer_buffer, port->bulk_out_size); urb->transfer_buffer_length = count; usb_serial_debug_data(&port->dev, __func__, count, urb->transfer_buffer); spin_lock_irqsave(&port->lock, flags); port->tx_bytes += count; spin_unlock_irqrestore(&port->lock, flags); clear_bit(i, &port->write_urbs_free); result = usb_submit_urb(urb, mem_flags); if (result) { dev_err_console(port, "%s - error submitting urb: %d\n", __func__, result); set_bit(i, &port->write_urbs_free); spin_lock_irqsave(&port->lock, flags); port->tx_bytes -= count; spin_unlock_irqrestore(&port->lock, flags); clear_bit_unlock(USB_SERIAL_WRITE_BUSY, &port->flags); return result; } goto retry; /* try sending off another urb */ } EXPORT_SYMBOL_GPL(usb_serial_generic_write_start); /** * usb_serial_generic_write - generic write function * @tty: tty for the port * @port: usb-serial port * @buf: data to write * @count: number of bytes to write * * Return: The number of characters buffered, which may be anything from * zero to @count, or a negative errno value. */ int usb_serial_generic_write(struct tty_struct *tty, struct usb_serial_port *port, const unsigned char *buf, int count) { int result; if (!port->bulk_out_size) return -ENODEV; if (!count) return 0; count = kfifo_in_locked(&port->write_fifo, buf, count, &port->lock); result = usb_serial_generic_write_start(port, GFP_ATOMIC); if (result) return result; return count; } EXPORT_SYMBOL_GPL(usb_serial_generic_write); unsigned int usb_serial_generic_write_room(struct tty_struct *tty) { struct usb_serial_port *port = tty->driver_data; unsigned long flags; unsigned int room; if (!port->bulk_out_size) return 0; spin_lock_irqsave(&port->lock, flags); room = kfifo_avail(&port->write_fifo); spin_unlock_irqrestore(&port->lock, flags); dev_dbg(&port->dev, "%s - returns %u\n", __func__, room); return room; } unsigned int usb_serial_generic_chars_in_buffer(struct tty_struct *tty) { struct usb_serial_port *port = tty->driver_data; unsigned long flags; unsigned int chars; if (!port->bulk_out_size) return 0; spin_lock_irqsave(&port->lock, flags); chars = kfifo_len(&port->write_fifo) + port->tx_bytes; spin_unlock_irqrestore(&port->lock, flags); dev_dbg(&port->dev, "%s - returns %u\n", __func__, chars); return chars; } EXPORT_SYMBOL_GPL(usb_serial_generic_chars_in_buffer); void usb_serial_generic_wait_until_sent(struct tty_struct *tty, long timeout) { struct usb_serial_port *port = tty->driver_data; unsigned int bps; unsigned long period; unsigned long expire; bps = tty_get_baud_rate(tty); if (!bps) bps = 9600; /* B0 */ /* * Use a poll-period of roughly the time it takes to send one * character or at least one jiffy. */ period = max_t(unsigned long, (10 * HZ / bps), 1); if (timeout) period = min_t(unsigned long, period, timeout); dev_dbg(&port->dev, "%s - timeout = %u ms, period = %u ms\n", __func__, jiffies_to_msecs(timeout), jiffies_to_msecs(period)); expire = jiffies + timeout; while (!port->serial->type->tx_empty(port)) { schedule_timeout_interruptible(period); if (signal_pending(current)) break; if (timeout && time_after(jiffies, expire)) break; } } EXPORT_SYMBOL_GPL(usb_serial_generic_wait_until_sent); static int usb_serial_generic_submit_read_urb(struct usb_serial_port *port, int index, gfp_t mem_flags) { int res; if (!test_and_clear_bit(index, &port->read_urbs_free)) return 0; dev_dbg(&port->dev, "%s - urb %d\n", __func__, index); res = usb_submit_urb(port->read_urbs[index], mem_flags); if (res) { if (res != -EPERM && res != -ENODEV) { dev_err(&port->dev, "%s - usb_submit_urb failed: %d\n", __func__, res); } set_bit(index, &port->read_urbs_free); return res; } return 0; } int usb_serial_generic_submit_read_urbs(struct usb_serial_port *port, gfp_t mem_flags) { int res; int i; for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i) { res = usb_serial_generic_submit_read_urb(port, i, mem_flags); if (res) goto err; } return 0; err: for (; i >= 0; --i) usb_kill_urb(port->read_urbs[i]); return res; } EXPORT_SYMBOL_GPL(usb_serial_generic_submit_read_urbs); void usb_serial_generic_process_read_urb(struct urb *urb) { struct usb_serial_port *port = urb->context; char *ch = urb->transfer_buffer; int i; if (!urb->actual_length) return; /* * The per character mucking around with sysrq path it too slow for * stuff like 3G modems, so shortcircuit it in the 99.9999999% of * cases where the USB serial is not a console anyway. */ if (port->sysrq) { for (i = 0; i < urb->actual_length; i++, ch++) { if (!usb_serial_handle_sysrq_char(port, *ch)) tty_insert_flip_char(&port->port, *ch, TTY_NORMAL); } } else { tty_insert_flip_string(&port->port, ch, urb->actual_length); } tty_flip_buffer_push(&port->port); } EXPORT_SYMBOL_GPL(usb_serial_generic_process_read_urb); void usb_serial_generic_read_bulk_callback(struct urb *urb) { struct usb_serial_port *port = urb->context; unsigned char *data = urb->transfer_buffer; bool stopped = false; int status = urb->status; int i; for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i) { if (urb == port->read_urbs[i]) break; } dev_dbg(&port->dev, "%s - urb %d, len %d\n", __func__, i, urb->actual_length); switch (status) { case 0: usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data); port->serial->type->process_read_urb(urb); break; case -ENOENT: case -ECONNRESET: case -ESHUTDOWN: dev_dbg(&port->dev, "%s - urb stopped: %d\n", __func__, status); stopped = true; break; case -EPIPE: dev_err(&port->dev, "%s - urb stopped: %d\n", __func__, status); stopped = true; break; default: dev_dbg(&port->dev, "%s - nonzero urb status: %d\n", __func__, status); break; } /* * Make sure URB processing is done before marking as free to avoid * racing with unthrottle() on another CPU. Matches the barriers * implied by the test_and_clear_bit() in * usb_serial_generic_submit_read_urb(). */ smp_mb__before_atomic(); set_bit(i, &port->read_urbs_free); /* * Make sure URB is marked as free before checking the throttled flag * to avoid racing with unthrottle() on another CPU. Matches the * smp_mb__after_atomic() in unthrottle(). */ smp_mb__after_atomic(); if (stopped) return; if (test_bit(USB_SERIAL_THROTTLED, &port->flags)) return; usb_serial_generic_submit_read_urb(port, i, GFP_ATOMIC); } EXPORT_SYMBOL_GPL(usb_serial_generic_read_bulk_callback); void usb_serial_generic_write_bulk_callback(struct urb *urb) { unsigned long flags; struct usb_serial_port *port = urb->context; int status = urb->status; int i; for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i) { if (port->write_urbs[i] == urb) break; } spin_lock_irqsave(&port->lock, flags); port->tx_bytes -= urb->transfer_buffer_length; set_bit(i, &port->write_urbs_free); spin_unlock_irqrestore(&port->lock, flags); switch (status) { case 0: break; case -ENOENT: case -ECONNRESET: case -ESHUTDOWN: dev_dbg(&port->dev, "%s - urb stopped: %d\n", __func__, status); return; case -EPIPE: dev_err_console(port, "%s - urb stopped: %d\n", __func__, status); return; default: dev_err_console(port, "%s - nonzero urb status: %d\n", __func__, status); break; } usb_serial_generic_write_start(port, GFP_ATOMIC); usb_serial_port_softint(port); } EXPORT_SYMBOL_GPL(usb_serial_generic_write_bulk_callback); void usb_serial_generic_throttle(struct tty_struct *tty) { struct usb_serial_port *port = tty->driver_data; set_bit(USB_SERIAL_THROTTLED, &port->flags); } EXPORT_SYMBOL_GPL(usb_serial_generic_throttle); void usb_serial_generic_unthrottle(struct tty_struct *tty) { struct usb_serial_port *port = tty->driver_data; clear_bit(USB_SERIAL_THROTTLED, &port->flags); /* * Matches the smp_mb__after_atomic() in * usb_serial_generic_read_bulk_callback(). */ smp_mb__after_atomic(); usb_serial_generic_submit_read_urbs(port, GFP_KERNEL); } EXPORT_SYMBOL_GPL(usb_serial_generic_unthrottle); static bool usb_serial_generic_msr_changed(struct tty_struct *tty, unsigned long arg, struct async_icount *cprev) { struct usb_serial_port *port = tty->driver_data; struct async_icount cnow;