From 10077d4a6674f535abdbe25cdecb1202af7948f1 Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Thu, 11 Jun 2009 12:36:09 +0100 Subject: [PATCH] tty: cdc_acm add krefs Now we have a port structure begin using the fields and kref counts Signed-off-by: Alan Cox Signed-off-by: Linus Torvalds --- drivers/usb/class/cdc-acm.c | 164 +++++++++++++++++++++--------------- drivers/usb/class/cdc-acm.h | 2 - 2 files changed, 98 insertions(+), 68 deletions(-) diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index 41d4ca527f82..b4e73aa759d6 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -62,7 +62,7 @@ #include #include #include -#include +#include #include #include #include @@ -87,7 +87,7 @@ static struct acm *acm_table[ACM_TTY_MINORS]; static DEFINE_MUTEX(open_mutex); -#define ACM_READY(acm) (acm && acm->dev && acm->used) +#define ACM_READY(acm) (acm && acm->dev && acm->port.count) static const struct tty_port_operations acm_port_ops = { }; @@ -265,6 +265,7 @@ static void acm_ctrl_irq(struct urb *urb) { struct acm *acm = urb->context; struct usb_cdc_notification *dr = urb->transfer_buffer; + struct tty_struct *tty; unsigned char *data; int newctrl; int retval; @@ -297,12 +298,16 @@ static void acm_ctrl_irq(struct urb *urb) break; case USB_CDC_NOTIFY_SERIAL_STATE: - + tty = tty_port_tty_get(&acm->port); newctrl = get_unaligned_le16(data); - if (acm->tty && !acm->clocal && (acm->ctrlin & ~newctrl & ACM_CTRL_DCD)) { - dbg("calling hangup"); - tty_hangup(acm->tty); + if (tty) { + if (!acm->clocal && + (acm->ctrlin & ~newctrl & ACM_CTRL_DCD)) { + dbg("calling hangup"); + tty_hangup(tty); + } + tty_kref_put(tty); } acm->ctrlin = newctrl; @@ -374,15 +379,14 @@ static void acm_rx_tasklet(unsigned long _acm) { struct acm *acm = (void *)_acm; struct acm_rb *buf; - struct tty_struct *tty = acm->tty; + struct tty_struct *tty; struct acm_ru *rcv; unsigned long flags; unsigned char throttled; dbg("Entering acm_rx_tasklet"); - if (!ACM_READY(acm)) - { + if (!ACM_READY(acm)) { dbg("acm_rx_tasklet: ACM not ready"); return; } @@ -390,12 +394,13 @@ static void acm_rx_tasklet(unsigned long _acm) spin_lock_irqsave(&acm->throttle_lock, flags); throttled = acm->throttle; spin_unlock_irqrestore(&acm->throttle_lock, flags); - if (throttled) - { + if (throttled) { dbg("acm_rx_tasklet: throttled"); return; } + tty = tty_port_tty_get(&acm->port); + next_buffer: spin_lock_irqsave(&acm->read_lock, flags); if (list_empty(&acm->filled_read_bufs)) { @@ -409,20 +414,22 @@ next_buffer: dbg("acm_rx_tasklet: procesing buf 0x%p, size = %d", buf, buf->size); - tty_buffer_request_room(tty, buf->size); - spin_lock_irqsave(&acm->throttle_lock, flags); - throttled = acm->throttle; - spin_unlock_irqrestore(&acm->throttle_lock, flags); - if (!throttled) - tty_insert_flip_string(tty, buf->base, buf->size); - tty_flip_buffer_push(tty); - - if (throttled) { - dbg("Throttling noticed"); - spin_lock_irqsave(&acm->read_lock, flags); - list_add(&buf->list, &acm->filled_read_bufs); - spin_unlock_irqrestore(&acm->read_lock, flags); - return; + if (tty) { + spin_lock_irqsave(&acm->throttle_lock, flags); + throttled = acm->throttle; + spin_unlock_irqrestore(&acm->throttle_lock, flags); + if (!throttled) { + tty_buffer_request_room(tty, buf->size); + tty_insert_flip_string(tty, buf->base, buf->size); + tty_flip_buffer_push(tty); + } else { + tty_kref_put(tty); + dbg("Throttling noticed"); + spin_lock_irqsave(&acm->read_lock, flags); + list_add(&buf->list, &acm->filled_read_bufs); + spin_unlock_irqrestore(&acm->read_lock, flags); + return; + } } spin_lock_irqsave(&acm->read_lock, flags); @@ -431,6 +438,8 @@ next_buffer: goto next_buffer; urbs: + tty_kref_put(tty); + while (!list_empty(&acm->spare_read_bufs)) { spin_lock_irqsave(&acm->read_lock, flags); if (list_empty(&acm->spare_read_urbs)) { @@ -502,11 +511,14 @@ static void acm_write_bulk(struct urb *urb) static void acm_softint(struct work_struct *work) { struct acm *acm = container_of(work, struct acm, work); + struct tty_struct *tty; dev_vdbg(&acm->data->dev, "tx work\n"); if (!ACM_READY(acm)) return; - tty_wakeup(acm->tty); + tty = tty_port_tty_get(&acm->port); + tty_wakeup(tty); + tty_kref_put(tty); } static void acm_waker(struct work_struct *waker) @@ -546,8 +558,9 @@ static int acm_tty_open(struct tty_struct *tty, struct file *filp) rv = 0; set_bit(TTY_NO_WRITE_SPLIT, &tty->flags); + tty->driver_data = acm; - acm->tty = tty; + tty_port_tty_set(&acm->port, tty); if (usb_autopm_get_interface(acm->control) < 0) goto early_bail; @@ -555,11 +568,10 @@ static int acm_tty_open(struct tty_struct *tty, struct file *filp) acm->control->needs_remote_wakeup = 1; mutex_lock(&acm->mutex); - if (acm->used++) { + if (acm->port.count++) { usb_autopm_put_interface(acm->control); goto done; - } - + } acm->ctrlurb->dev = acm->dev; if (usb_submit_urb(acm->ctrlurb, GFP_KERNEL)) { @@ -570,6 +582,7 @@ static int acm_tty_open(struct tty_struct *tty, struct file *filp) if (0 > acm_set_control(acm, acm->ctrlout = ACM_CTRL_DTR | ACM_CTRL_RTS) && (acm->ctrl_caps & USB_CDC_CAP_LINE)) goto full_bailout; + usb_autopm_put_interface(acm->control); INIT_LIST_HEAD(&acm->spare_read_urbs); @@ -585,7 +598,7 @@ static int acm_tty_open(struct tty_struct *tty, struct file *filp) acm->throttle = 0; tasklet_schedule(&acm->urb_task); - + rv = tty_port_block_til_ready(&acm->port, tty, filp); done: mutex_unlock(&acm->mutex); err_out: @@ -596,16 +609,17 @@ full_bailout: usb_kill_urb(acm->ctrlurb); bail_out: usb_autopm_put_interface(acm->control); - acm->used--; + acm->port.count--; mutex_unlock(&acm->mutex); early_bail: mutex_unlock(&open_mutex); + tty_port_tty_set(&acm->port, NULL); return -EIO; } static void acm_tty_unregister(struct acm *acm) { - int i,nr; + int i, nr; nr = acm->rx_buflimit; tty_unregister_device(acm_tty_driver, acm->minor); @@ -622,37 +636,51 @@ static void acm_tty_unregister(struct acm *acm) static int acm_tty_chars_in_buffer(struct tty_struct *tty); +static void acm_port_down(struct acm *acm, int drain) +{ + int i, nr = acm->rx_buflimit; + mutex_lock(&open_mutex); + if (acm->dev) { + usb_autopm_get_interface(acm->control); + acm_set_control(acm, acm->ctrlout = 0); + /* try letting the last writes drain naturally */ + if (drain) { + wait_event_interruptible_timeout(acm->drain_wait, + (ACM_NW == acm_wb_is_avail(acm)) || !acm->dev, + ACM_CLOSE_TIMEOUT * HZ); + } + usb_kill_urb(acm->ctrlurb); + for (i = 0; i < ACM_NW; i++) + usb_kill_urb(acm->wb[i].urb); + for (i = 0; i < nr; i++) + usb_kill_urb(acm->ru[i].urb); + acm->control->needs_remote_wakeup = 0; + usb_autopm_put_interface(acm->control); + } + mutex_unlock(&open_mutex); +} + +static void acm_tty_hangup(struct tty_struct *tty) +{ + struct acm *acm = tty->driver_data; + tty_port_hangup(&acm->port); + acm_port_down(acm, 0); +} + static void acm_tty_close(struct tty_struct *tty, struct file *filp) { struct acm *acm = tty->driver_data; - int i,nr; - if (!acm || !acm->used) + /* Perform the closing process and see if we need to do the hardware + shutdown */ + if (tty_port_close_start(&acm->port, tty, filp) == 0) return; - - nr = acm->rx_buflimit; + acm_port_down(acm, 0); + tty_port_close_end(&acm->port, tty); mutex_lock(&open_mutex); - if (!--acm->used) { - if (acm->dev) { - usb_autopm_get_interface(acm->control); - acm_set_control(acm, acm->ctrlout = 0); - - /* try letting the last writes drain naturally */ - wait_event_interruptible_timeout(acm->drain_wait, - (ACM_NW == acm_wb_is_avail(acm)) - || !acm->dev, - ACM_CLOSE_TIMEOUT * HZ); - - usb_kill_urb(acm->ctrlurb); - for (i = 0; i < ACM_NW; i++) - usb_kill_urb(acm->wb[i].urb); - for (i = 0; i < nr; i++) - usb_kill_urb(acm->ru[i].urb); - acm->control->needs_remote_wakeup = 0; - usb_autopm_put_interface(acm->control); - } else - acm_tty_unregister(acm); - } + tty_port_tty_set(&acm->port, NULL); + if (!acm->dev) + acm_tty_unregister(acm); mutex_unlock(&open_mutex); } @@ -885,8 +913,8 @@ static int acm_write_buffers_alloc(struct acm *acm) return 0; } -static int acm_probe (struct usb_interface *intf, - const struct usb_device_id *id) +static int acm_probe(struct usb_interface *intf, + const struct usb_device_id *id) { struct usb_cdc_union_desc *union_header = NULL; struct usb_cdc_country_functional_desc *cfd = NULL; @@ -1232,6 +1260,7 @@ 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; /* sibling interface is already cleaning up */ if (!acm) @@ -1258,16 +1287,18 @@ static void acm_disconnect(struct usb_interface *intf) usb_driver_release_interface(&acm_driver, intf == acm->control ? acm->data : acm->control); - if (!acm->used) { + if (acm->port.count == 0) { acm_tty_unregister(acm); mutex_unlock(&open_mutex); return; } mutex_unlock(&open_mutex); - - if (acm->tty) - tty_hangup(acm->tty); + tty = tty_port_tty_get(&acm->port); + if (tty) { + tty_hangup(tty); + tty_kref_put(tty); + } } #ifdef CONFIG_PM @@ -1302,7 +1333,7 @@ static int acm_suspend(struct usb_interface *intf, pm_message_t message) */ mutex_lock(&acm->mutex); - if (acm->used) + if (acm->port.count) stop_data_traffic(acm); mutex_unlock(&acm->mutex); @@ -1324,7 +1355,7 @@ static int acm_resume(struct usb_interface *intf) return 0; mutex_lock(&acm->mutex); - if (acm->used) { + if (acm->port.count) { rv = usb_submit_urb(acm->ctrlurb, GFP_NOIO); if (rv < 0) goto err_out; @@ -1434,6 +1465,7 @@ static struct usb_driver acm_driver = { static const struct tty_operations acm_ops = { .open = acm_tty_open, .close = acm_tty_close, + .hangup = acm_tty_hangup, .write = acm_tty_write, .write_room = acm_tty_write_room, .ioctl = acm_tty_ioctl, diff --git a/drivers/usb/class/cdc-acm.h b/drivers/usb/class/cdc-acm.h index 19967cdb2691..4c3856420add 100644 --- a/drivers/usb/class/cdc-acm.h +++ b/drivers/usb/class/cdc-acm.h @@ -89,7 +89,6 @@ struct acm { struct usb_device *dev; /* the corresponding usb device */ struct usb_interface *control; /* control interface */ struct usb_interface *data; /* data interface */ - struct tty_struct *tty; /* the corresponding tty */ struct tty_port port; /* our tty port data */ struct urb *ctrlurb; /* urbs */ u8 *ctrl_buffer; /* buffers of urbs */ @@ -121,7 +120,6 @@ struct acm { unsigned int ctrlout; /* output control lines (DTR, RTS) */ unsigned int writesize; /* max packet size for the output bulk endpoint */ unsigned int readsize,ctrlsize; /* buffer sizes for freeing */ - unsigned int used; /* someone has this acm's device open */ unsigned int minor; /* acm minor number */ unsigned char throttle; /* throttled by tty layer */ unsigned char clocal; /* termios CLOCAL */