diff options
Diffstat (limited to 'drivers/usb/class/cdc-acm.c')
-rw-r--r-- | drivers/usb/class/cdc-acm.c | 338 |
1 files changed, 192 insertions, 146 deletions
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index a8078d0..9543b19 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -58,12 +58,62 @@ static struct usb_driver acm_driver; static struct tty_driver *acm_tty_driver; static struct acm *acm_table[ACM_TTY_MINORS]; -static DEFINE_MUTEX(open_mutex); +static DEFINE_MUTEX(acm_table_lock); -#define ACM_READY(acm) (acm && acm->dev && acm->port.count) +/* + * acm_table accessors + */ -static const struct tty_port_operations acm_port_ops = { -}; +/* + * Look up an ACM structure by index. If found and not disconnected, increment + * its refcount and return it with its mutex held. + */ +static struct acm *acm_get_by_index(unsigned index) +{ + struct acm *acm; + + mutex_lock(&acm_table_lock); + acm = acm_table[index]; + if (acm) { + mutex_lock(&acm->mutex); + if (acm->disconnected) { + mutex_unlock(&acm->mutex); + acm = NULL; + } else { + tty_port_get(&acm->port); + mutex_unlock(&acm->mutex); + } + } + mutex_unlock(&acm_table_lock); + return acm; +} + +/* + * Try to find an available minor number and if found, associate it with 'acm'. + */ +static int acm_alloc_minor(struct acm *acm) +{ + int minor; + + mutex_lock(&acm_table_lock); + for (minor = 0; minor < ACM_TTY_MINORS; minor++) { + if (!acm_table[minor]) { + acm_table[minor] = acm; + break; + } + } + mutex_unlock(&acm_table_lock); + + return minor; +} + +/* Release the minor number associated with 'acm'. */ +static void acm_release_minor(struct acm *acm) +{ + mutex_lock(&acm_table_lock); + acm_table[acm->minor] = NULL; + mutex_unlock(&acm_table_lock); +} /* * Functions for ACM control messages. @@ -267,9 +317,6 @@ static void acm_ctrl_irq(struct urb *urb) goto exit; } - if (!ACM_READY(acm)) - goto exit; - usb_mark_last_busy(acm->dev); data = (unsigned char *)(dr + 1); @@ -429,8 +476,7 @@ static void acm_write_bulk(struct urb *urb) spin_lock_irqsave(&acm->write_lock, flags); acm_write_done(acm, wb); spin_unlock_irqrestore(&acm->write_lock, flags); - if (ACM_READY(acm)) - schedule_work(&acm->work); + schedule_work(&acm->work); } static void acm_softint(struct work_struct *work) @@ -440,8 +486,6 @@ static void acm_softint(struct work_struct *work) dev_vdbg(&acm->data->dev, "%s\n", __func__); - if (!ACM_READY(acm)) - return; tty = tty_port_tty_get(&acm->port); if (!tty) return; @@ -453,93 +497,122 @@ static void acm_softint(struct work_struct *work) * TTY handlers */ -static int acm_tty_open(struct tty_struct *tty, struct file *filp) +static int acm_tty_install(struct tty_driver *driver, struct tty_struct *tty) { struct acm *acm; - int rv = -ENODEV; - - mutex_lock(&open_mutex); + int retval; - acm = acm_table[tty->index]; - if (!acm || !acm->dev) - goto out; - else - rv = 0; + dev_dbg(tty->dev, "%s\n", __func__); - dev_dbg(&acm->control->dev, "%s\n", __func__); + acm = acm_get_by_index(tty->index); + if (!acm) + return -ENODEV; - set_bit(TTY_NO_WRITE_SPLIT, &tty->flags); + retval = tty_init_termios(tty); + if (retval) + goto error_init_termios; tty->driver_data = acm; - tty_port_tty_set(&acm->port, tty); - if (usb_autopm_get_interface(acm->control) < 0) - goto early_bail; - else - acm->control->needs_remote_wakeup = 1; + /* Final install (we use the default method) */ + tty_driver_kref_get(driver); + tty->count++; + driver->ttys[tty->index] = tty; + + return 0; + +error_init_termios: + tty_port_put(&acm->port); + return retval; +} + +static int acm_tty_open(struct tty_struct *tty, struct file *filp) +{ + struct acm *acm = tty->driver_data; + + dev_dbg(tty->dev, "%s\n", __func__); + + return tty_port_open(&acm->port, tty, filp); +} + +static int acm_port_activate(struct tty_port *port, struct tty_struct *tty) +{ + struct acm *acm = container_of(port, struct acm, port); + int retval = -ENODEV; + + dev_dbg(&acm->control->dev, "%s\n", __func__); mutex_lock(&acm->mutex); - if (acm->port.count++) { - mutex_unlock(&acm->mutex); - usb_autopm_put_interface(acm->control); - goto out; - } + if (acm->disconnected) + goto disconnected; + + retval = usb_autopm_get_interface(acm->control); + if (retval) + goto error_get_interface; + + /* + * FIXME: Why do we need this? Allocating 64K of physically contiguous + * memory is really nasty... + */ + set_bit(TTY_NO_WRITE_SPLIT, &tty->flags); + acm->control->needs_remote_wakeup = 1; acm->ctrlurb->dev = acm->dev; if (usb_submit_urb(acm->ctrlurb, GFP_KERNEL)) { dev_err(&acm->control->dev, "%s - usb_submit_urb(ctrl irq) failed\n", __func__); - goto bail_out; + goto error_submit_urb; } - if (0 > acm_set_control(acm, acm->ctrlout = ACM_CTRL_DTR | ACM_CTRL_RTS) && + acm->ctrlout = ACM_CTRL_DTR | ACM_CTRL_RTS; + if (acm_set_control(acm, acm->ctrlout) < 0 && (acm->ctrl_caps & USB_CDC_CAP_LINE)) - goto bail_out; + goto error_set_control; usb_autopm_put_interface(acm->control); if (acm_submit_read_urbs(acm, GFP_KERNEL)) - goto bail_out; - - set_bit(ASYNCB_INITIALIZED, &acm->port.flags); - rv = tty_port_block_til_ready(&acm->port, tty, filp); + goto error_submit_read_urbs; mutex_unlock(&acm->mutex); -out: - mutex_unlock(&open_mutex); - return rv; -bail_out: - acm->port.count--; - mutex_unlock(&acm->mutex); + return 0; + +error_submit_read_urbs: + acm->ctrlout = 0; + acm_set_control(acm, acm->ctrlout); +error_set_control: + usb_kill_urb(acm->ctrlurb); +error_submit_urb: usb_autopm_put_interface(acm->control); -early_bail: - mutex_unlock(&open_mutex); - tty_port_tty_set(&acm->port, NULL); - return -EIO; +error_get_interface: +disconnected: + mutex_unlock(&acm->mutex); + return retval; } -static void acm_tty_unregister(struct acm *acm) +static void acm_port_destruct(struct tty_port *port) { - int i; + struct acm *acm = container_of(port, struct acm, port); + + dev_dbg(&acm->control->dev, "%s\n", __func__); tty_unregister_device(acm_tty_driver, acm->minor); + acm_release_minor(acm); usb_put_intf(acm->control); - acm_table[acm->minor] = NULL; - usb_free_urb(acm->ctrlurb); - for (i = 0; i < ACM_NW; i++) - usb_free_urb(acm->wb[i].urb); - for (i = 0; i < acm->rx_buflimit; i++) - usb_free_urb(acm->read_urbs[i]); kfree(acm->country_codes); kfree(acm); } -static void acm_port_down(struct acm *acm) +static void acm_port_shutdown(struct tty_port *port) { + struct acm *acm = container_of(port, struct acm, port); int i; - if (acm->dev) { + dev_dbg(&acm->control->dev, "%s\n", __func__); + + mutex_lock(&acm->mutex); + if (!acm->disconnected) { usb_autopm_get_interface(acm->control); acm_set_control(acm, acm->ctrlout = 0); usb_kill_urb(acm->ctrlurb); @@ -550,40 +623,28 @@ static void acm_port_down(struct acm *acm) acm->control->needs_remote_wakeup = 0; usb_autopm_put_interface(acm->control); } + mutex_unlock(&acm->mutex); +} + +static void acm_tty_cleanup(struct tty_struct *tty) +{ + struct acm *acm = tty->driver_data; + dev_dbg(&acm->control->dev, "%s\n", __func__); + tty_port_put(&acm->port); } static void acm_tty_hangup(struct tty_struct *tty) { struct acm *acm = tty->driver_data; + dev_dbg(&acm->control->dev, "%s\n", __func__); tty_port_hangup(&acm->port); - mutex_lock(&open_mutex); - acm_port_down(acm); - mutex_unlock(&open_mutex); } static void acm_tty_close(struct tty_struct *tty, struct file *filp) { struct acm *acm = tty->driver_data; - - /* Perform the closing process and see if we need to do the hardware - shutdown */ - if (!acm) - return; - - mutex_lock(&open_mutex); - if (tty_port_close_start(&acm->port, tty, filp) == 0) { - if (!acm->dev) { - tty_port_tty_set(&acm->port, NULL); - acm_tty_unregister(acm); - tty->driver_data = NULL; - } - mutex_unlock(&open_mutex); - return; - } - acm_port_down(acm); - tty_port_close_end(&acm->port, tty); - tty_port_tty_set(&acm->port, NULL); - mutex_unlock(&open_mutex); + dev_dbg(&acm->control->dev, "%s\n", __func__); + tty_port_close(&acm->port, tty, filp); } static int acm_tty_write(struct tty_struct *tty, @@ -595,8 +656,6 @@ static int acm_tty_write(struct tty_struct *tty, int wbn; struct acm_wb *wb; - if (!ACM_READY(acm)) - return -EINVAL; if (!count) return 0; @@ -625,8 +684,6 @@ static int acm_tty_write(struct tty_struct *tty, static int acm_tty_write_room(struct tty_struct *tty) { struct acm *acm = tty->driver_data; - if (!ACM_READY(acm)) - return -EINVAL; /* * Do not let the line discipline to know that we have a reserve, * or it might get too enthusiastic. @@ -637,7 +694,11 @@ static int acm_tty_write_room(struct tty_struct *tty) static int acm_tty_chars_in_buffer(struct tty_struct *tty) { struct acm *acm = tty->driver_data; - if (!ACM_READY(acm)) + /* + * if the device was unplugged then any remaining characters fell out + * of the connector ;) + */ + if (acm->disconnected) return 0; /* * This is inaccurate (overcounts), but it works. @@ -649,9 +710,6 @@ static void acm_tty_throttle(struct tty_struct *tty) { struct acm *acm = tty->driver_data; - if (!ACM_READY(acm)) - return; - spin_lock_irq(&acm->read_lock); acm->throttle_req = 1; spin_unlock_irq(&acm->read_lock); @@ -662,9 +720,6 @@ static void acm_tty_unthrottle(struct tty_struct *tty) struct acm *acm = tty->driver_data; unsigned int was_throttled; - if (!ACM_READY(acm)) - return; - spin_lock_irq(&acm->read_lock); was_throttled = acm->throttled; acm->throttled = 0; @@ -679,8 +734,7 @@ static int acm_tty_break_ctl(struct tty_struct *tty, int state) { struct acm *acm = tty->driver_data; int retval; - if (!ACM_READY(acm)) - return -EINVAL; + retval = acm_send_break(acm, state ? 0xffff : 0); if (retval < 0) dev_dbg(&acm->control->dev, "%s - send break failed\n", @@ -692,9 +746,6 @@ static int acm_tty_tiocmget(struct tty_struct *tty) { struct acm *acm = tty->driver_data; - if (!ACM_READY(acm)) - return -EINVAL; - return (acm->ctrlout & ACM_CTRL_DTR ? TIOCM_DTR : 0) | (acm->ctrlout & ACM_CTRL_RTS ? TIOCM_RTS : 0) | (acm->ctrlin & ACM_CTRL_DSR ? TIOCM_DSR : 0) | @@ -709,9 +760,6 @@ static int acm_tty_tiocmset(struct tty_struct *tty, struct acm *acm = tty->driver_data; unsigned int newctrl; - if (!ACM_READY(acm)) - return -EINVAL; - newctrl = acm->ctrlout; set = (set & TIOCM_DTR ? ACM_CTRL_DTR : 0) | (set & TIOCM_RTS ? ACM_CTRL_RTS : 0); @@ -728,11 +776,6 @@ static int acm_tty_tiocmset(struct tty_struct *tty, static int acm_tty_ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg) { - struct acm *acm = tty->driver_data; - - if (!ACM_READY(acm)) - return -EINVAL; - return -ENOIOCTLCMD; } @@ -756,9 +799,6 @@ static void acm_tty_set_termios(struct tty_struct *tty, struct usb_cdc_line_coding newline; int newctrl = acm->ctrlout; - if (!ACM_READY(acm)) - return; - newline.dwDTERate = cpu_to_le32(tty_get_baud_rate(tty)); newline.bCharFormat = termios->c_cflag & CSTOPB ? 2 : 0; newline.bParityType = termios->c_cflag & PARENB ? @@ -788,6 +828,12 @@ static void acm_tty_set_termios(struct tty_struct *tty, } } +static const struct tty_port_operations acm_port_ops = { + .shutdown = acm_port_shutdown, + .activate = acm_port_activate, + .destruct = acm_port_destruct, +}; + /* * USB probe and disconnect routines. */ @@ -1047,12 +1093,6 @@ skip_normal_probe: } made_compressed_probe: dev_dbg(&intf->dev, "interfaces are valid\n"); - for (minor = 0; minor < ACM_TTY_MINORS && acm_table[minor]; minor++); - - if (minor == ACM_TTY_MINORS) { - dev_err(&intf->dev, "no more free acm devices\n"); - return -ENODEV; - } acm = kzalloc(sizeof(struct acm), GFP_KERNEL); if (acm == NULL) { @@ -1060,6 +1100,13 @@ made_compressed_probe: goto alloc_fail; } + minor = acm_alloc_minor(acm); + if (minor == ACM_TTY_MINORS) { + dev_err(&intf->dev, "no more free acm devices\n"); + kfree(acm); + return -ENODEV; + } + ctrlsize = usb_endpoint_maxp(epctrl); readsize = usb_endpoint_maxp(epread) * (quirks == SINGLE_RX_URB ? 1 : 2); @@ -1183,6 +1230,8 @@ made_compressed_probe: i = device_create_file(&intf->dev, &dev_attr_wCountryCodes); if (i < 0) { kfree(acm->country_codes); + acm->country_codes = NULL; + acm->country_code_size = 0; goto skip_countries; } @@ -1191,6 +1240,8 @@ made_compressed_probe: if (i < 0) { device_remove_file(&intf->dev, &dev_attr_wCountryCodes); kfree(acm->country_codes); + acm->country_codes = NULL; + acm->country_code_size = 0; goto skip_countries; } } @@ -1218,8 +1269,6 @@ skip_countries: usb_get_intf(control_interface); tty_register_device(acm_tty_driver, minor, &control_interface->dev); - acm_table[minor] = acm; - return 0; alloc_fail7: for (i = 0; i < ACM_NW; i++) @@ -1234,6 +1283,7 @@ alloc_fail5: alloc_fail4: usb_free_coherent(usb_dev, ctrlsize, acm->ctrl_buffer, acm->ctrl_dma); alloc_fail2: + acm_release_minor(acm); kfree(acm); alloc_fail: return -ENOMEM; @@ -1259,12 +1309,16 @@ static void acm_disconnect(struct usb_interface *intf) struct acm *acm = usb_get_intfdata(intf); struct usb_device *usb_dev = interface_to_usbdev(intf); struct tty_struct *tty; + int i; + + dev_dbg(&intf->dev, "%s\n", __func__); /* sibling interface is already cleaning up */ if (!acm) return; - mutex_lock(&open_mutex); + mutex_lock(&acm->mutex); + acm->disconnected = true; if (acm->country_codes) { device_remove_file(&acm->control->dev, &dev_attr_wCountryCodes); @@ -1272,33 +1326,32 @@ static void acm_disconnect(struct usb_interface *intf) &dev_attr_iCountryCodeRelDate); } device_remove_file(&acm->control->dev, &dev_attr_bmCapabilities); - acm->dev = NULL; usb_set_intfdata(acm->control, NULL); usb_set_intfdata(acm->data, NULL); + mutex_unlock(&acm->mutex); + + tty = tty_port_tty_get(&acm->port); + if (tty) { + tty_vhangup(tty); + tty_kref_put(tty); + } stop_data_traffic(acm); + usb_free_urb(acm->ctrlurb); + for (i = 0; i < ACM_NW; i++) + usb_free_urb(acm->wb[i].urb); + for (i = 0; i < acm->rx_buflimit; i++) + usb_free_urb(acm->read_urbs[i]); acm_write_buffers_free(acm); - usb_free_coherent(usb_dev, acm->ctrlsize, acm->ctrl_buffer, - acm->ctrl_dma); + usb_free_coherent(usb_dev, acm->ctrlsize, acm->ctrl_buffer, acm->ctrl_dma); acm_read_buffers_free(acm); if (!acm->combined_interfaces) usb_driver_release_interface(&acm_driver, intf == acm->control ? acm->data : acm->control); - if (acm->port.count == 0) { - acm_tty_unregister(acm); - mutex_unlock(&open_mutex); - return; - } - - mutex_unlock(&open_mutex); - tty = tty_port_tty_get(&acm->port); - if (tty) { - tty_hangup(tty); - tty_kref_put(tty); - } + tty_port_put(&acm->port); } #ifdef CONFIG_PM @@ -1325,16 +1378,10 @@ static int acm_suspend(struct usb_interface *intf, pm_message_t message) if (cnt) return 0; - /* - we treat opened interfaces differently, - we must guard against open - */ - mutex_lock(&acm->mutex); - if (acm->port.count) + if (test_bit(ASYNCB_INITIALIZED, &acm->port.flags)) stop_data_traffic(acm); - mutex_unlock(&acm->mutex); return 0; } @@ -1353,8 +1400,7 @@ static int acm_resume(struct usb_interface *intf) if (cnt) return 0; - mutex_lock(&acm->mutex); - if (acm->port.count) { + if (test_bit(ASYNCB_INITIALIZED, &acm->port.flags)) { rv = usb_submit_urb(acm->ctrlurb, GFP_NOIO); spin_lock_irq(&acm->write_lock); @@ -1378,7 +1424,6 @@ static int acm_resume(struct usb_interface *intf) } err_out: - mutex_unlock(&acm->mutex); return rv; } @@ -1387,15 +1432,14 @@ static int acm_reset_resume(struct usb_interface *intf) struct acm *acm = usb_get_intfdata(intf); struct tty_struct *tty; - mutex_lock(&acm->mutex); - if (acm->port.count) { + if (test_bit(ASYNCB_INITIALIZED, &acm->port.flags)) { tty = tty_port_tty_get(&acm->port); if (tty) { tty_hangup(tty); tty_kref_put(tty); } } - mutex_unlock(&acm->mutex); + return acm_resume(intf); } @@ -1604,8 +1648,10 @@ static struct usb_driver acm_driver = { */ static const struct tty_operations acm_ops = { + .install = acm_tty_install, .open = acm_tty_open, .close = acm_tty_close, + .cleanup = acm_tty_cleanup, .hangup = acm_tty_hangup, .write = acm_tty_write, .write_room = acm_tty_write_room, |