diff options
Diffstat (limited to 'drivers/usb')
| -rw-r--r-- | drivers/usb/class/cdc-acm.c | 142 | ||||
| -rw-r--r-- | drivers/usb/class/cdc-acm.h | 5 |
2 files changed, 126 insertions, 21 deletions
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index c3201affa0b..ba86fec872b 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -159,12 +159,34 @@ static void acm_write_done(struct acm *acm, struct acm_wb *wb) spin_lock_irqsave(&acm->write_lock, flags); acm->write_ready = 1; wb->use = 0; + acm->transmitting--; spin_unlock_irqrestore(&acm->write_lock, flags); } /* * Poke write. + * + * the caller is responsible for locking */ + +static int acm_start_wb(struct acm *acm, struct acm_wb *wb) +{ + int rc; + + acm->transmitting++; + + wb->urb->transfer_buffer = wb->buf; + wb->urb->transfer_dma = wb->dmah; + wb->urb->transfer_buffer_length = wb->len; + wb->urb->dev = acm->dev; + + if ((rc = usb_submit_urb(wb->urb, GFP_ATOMIC)) < 0) { + dbg("usb_submit_urb(write bulk) failed: %d", rc); + acm_write_done(acm, wb); + } + return rc; +} + static int acm_write_start(struct acm *acm, int wbn) { unsigned long flags; @@ -182,26 +204,31 @@ static int acm_write_start(struct acm *acm, int wbn) return 0; /* A white lie */ } + wb = &acm->wb[wbn]; + if(acm_wb_is_avail(acm) <= 1) + acm->write_ready = 0; + + dbg("%s susp_count: %d", __func__, acm->susp_count); + if (acm->susp_count) { + acm->old_ready = acm->write_ready; + acm->delayed_wb = wb; + acm->write_ready = 0; + schedule_work(&acm->waker); + spin_unlock_irqrestore(&acm->write_lock, flags); + return 0; /* A white lie */ + } + usb_mark_last_busy(acm->dev); + if (!acm_wb_is_used(acm, wbn)) { spin_unlock_irqrestore(&acm->write_lock, flags); return 0; } - wb = &acm->wb[wbn]; - if(acm_wb_is_avail(acm) <= 1) - acm->write_ready = 0; + rc = acm_start_wb(acm, wb); spin_unlock_irqrestore(&acm->write_lock, flags); - wb->urb->transfer_buffer = wb->buf; - wb->urb->transfer_dma = wb->dmah; - wb->urb->transfer_buffer_length = wb->len; - wb->urb->dev = acm->dev; - - if ((rc = usb_submit_urb(wb->urb, GFP_ATOMIC)) < 0) { - dbg("usb_submit_urb(write bulk) failed: %d", rc); - acm_write_done(acm, wb); - } return rc; + } /* * attributes exported through sysfs @@ -304,6 +331,7 @@ static void acm_ctrl_irq(struct urb *urb) break; } exit: + usb_mark_last_busy(acm->dev); retval = usb_submit_urb (urb, GFP_ATOMIC); if (retval) err ("%s - usb_submit_urb failed with result %d", @@ -320,8 +348,11 @@ static void acm_read_bulk(struct urb *urb) dbg("Entering acm_read_bulk with status %d", status); - if (!ACM_READY(acm)) + if (!ACM_READY(acm)) { + dev_dbg(&acm->data->dev, "Aborting, acm not ready"); return; + } + usb_mark_last_busy(acm->dev); if (status) dev_dbg(&acm->data->dev, "bulk rx status %d\n", status); @@ -331,6 +362,7 @@ static void acm_read_bulk(struct urb *urb) if (likely(status == 0)) { spin_lock(&acm->read_lock); + acm->processing++; list_add_tail(&rcv->list, &acm->spare_read_urbs); list_add_tail(&buf->list, &acm->filled_read_bufs); spin_unlock(&acm->read_lock); @@ -343,7 +375,8 @@ static void acm_read_bulk(struct urb *urb) /* nevertheless the tasklet must be kicked unconditionally so the queue cannot dry up */ } - tasklet_schedule(&acm->urb_task); + if (likely(!acm->susp_count)) + tasklet_schedule(&acm->urb_task); } static void acm_rx_tasklet(unsigned long _acm) @@ -354,16 +387,23 @@ static void acm_rx_tasklet(unsigned long _acm) struct acm_ru *rcv; unsigned long flags; unsigned char throttled; + dbg("Entering acm_rx_tasklet"); if (!ACM_READY(acm)) + { + dbg("acm_rx_tasklet: ACM not ready"); return; + } spin_lock_irqsave(&acm->throttle_lock, flags); throttled = acm->throttle; spin_unlock_irqrestore(&acm->throttle_lock, flags); if (throttled) + { + dbg("acm_rx_tasklet: throttled"); return; + } next_buffer: spin_lock_irqsave(&acm->read_lock, flags); @@ -403,6 +443,7 @@ urbs: while (!list_empty(&acm->spare_read_bufs)) { spin_lock_irqsave(&acm->read_lock, flags); if (list_empty(&acm->spare_read_urbs)) { + acm->processing = 0; spin_unlock_irqrestore(&acm->read_lock, flags); return; } @@ -425,18 +466,23 @@ urbs: rcv->urb->transfer_dma = buf->dma; rcv->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; - dbg("acm_rx_tasklet: sending urb 0x%p, rcv 0x%p, buf 0x%p", rcv->urb, rcv, buf); - /* This shouldn't kill the driver as unsuccessful URBs are returned to the free-urbs-pool and resubmited ASAP */ - if (usb_submit_urb(rcv->urb, GFP_ATOMIC) < 0) { + spin_lock_irqsave(&acm->read_lock, flags); + if (acm->susp_count || usb_submit_urb(rcv->urb, GFP_ATOMIC) < 0) { list_add(&buf->list, &acm->spare_read_bufs); - spin_lock_irqsave(&acm->read_lock, flags); list_add(&rcv->list, &acm->spare_read_urbs); + acm->processing = 0; spin_unlock_irqrestore(&acm->read_lock, flags); return; + } else { + spin_unlock_irqrestore(&acm->read_lock, flags); + dbg("acm_rx_tasklet: sending urb 0x%p, rcv 0x%p, buf 0x%p", rcv->urb, rcv, buf); } } + spin_lock_irqsave(&acm->read_lock, flags); + acm->processing = 0; + spin_unlock_irqrestore(&acm->read_lock, flags); } /* data interface wrote those outgoing bytes */ @@ -463,6 +509,27 @@ static void acm_softint(struct work_struct *work) tty_wakeup(acm->tty); } +static void acm_waker(struct work_struct *waker) +{ + struct acm *acm = container_of(waker, struct acm, waker); + long flags; + int rv; + + rv = usb_autopm_get_interface(acm->control); + if (rv < 0) { + err("Autopm failure in %s", __func__); + return; + } + if (acm->delayed_wb) { + acm_start_wb(acm, acm->delayed_wb); + acm->delayed_wb = NULL; + } + spin_lock_irqsave(&acm->write_lock, flags); + acm->write_ready = acm->old_ready; + spin_unlock_irqrestore(&acm->write_lock, flags); + usb_autopm_put_interface(acm->control); +} + /* * TTY handlers */ @@ -492,6 +559,8 @@ static int acm_tty_open(struct tty_struct *tty, struct file *filp) if (usb_autopm_get_interface(acm->control) < 0) goto early_bail; + else + acm->control->needs_remote_wakeup = 1; mutex_lock(&acm->mutex); if (acm->used++) { @@ -509,6 +578,7 @@ 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); INIT_LIST_HEAD(&acm->spare_read_bufs); @@ -570,12 +640,14 @@ static void acm_tty_close(struct tty_struct *tty, struct file *filp) mutex_lock(&open_mutex); if (!--acm->used) { if (acm->dev) { + usb_autopm_get_interface(acm->control); acm_set_control(acm, acm->ctrlout = 0); 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); @@ -987,6 +1059,7 @@ skip_normal_probe: acm->urb_task.func = acm_rx_tasklet; acm->urb_task.data = (unsigned long) acm; INIT_WORK(&acm->work, acm_softint); + INIT_WORK(&acm->waker, acm_waker); spin_lock_init(&acm->throttle_lock); spin_lock_init(&acm->write_lock); spin_lock_init(&acm->read_lock); @@ -1116,6 +1189,7 @@ alloc_fail: static void stop_data_traffic(struct acm *acm) { int i; + dbg("Entering stop_data_traffic"); tasklet_disable(&acm->urb_task); @@ -1128,6 +1202,7 @@ static void stop_data_traffic(struct acm *acm) tasklet_enable(&acm->urb_task); cancel_work_sync(&acm->work); + cancel_work_sync(&acm->waker); } static void acm_disconnect(struct usb_interface *intf) @@ -1181,8 +1256,27 @@ static void acm_disconnect(struct usb_interface *intf) static int acm_suspend(struct usb_interface *intf, pm_message_t message) { struct acm *acm = usb_get_intfdata(intf); + int cnt; + + if (acm->dev->auto_pm) { + int b; + + spin_lock_irq(&acm->read_lock); + spin_lock(&acm->write_lock); + b = acm->processing + acm->transmitting; + spin_unlock(&acm->write_lock); + spin_unlock_irq(&acm->read_lock); + if (b) + return -EBUSY; + } + + spin_lock_irq(&acm->read_lock); + spin_lock(&acm->write_lock); + cnt = acm->susp_count++; + spin_unlock(&acm->write_lock); + spin_unlock_irq(&acm->read_lock); - if (acm->susp_count++) + if (cnt) return 0; /* we treat opened interfaces differently, @@ -1201,15 +1295,21 @@ static int acm_resume(struct usb_interface *intf) { struct acm *acm = usb_get_intfdata(intf); int rv = 0; + int cnt; - if (--acm->susp_count) + spin_lock_irq(&acm->read_lock); + acm->susp_count -= 1; + cnt = acm->susp_count; + spin_unlock_irq(&acm->read_lock); + + if (cnt) return 0; mutex_lock(&acm->mutex); if (acm->used) { rv = usb_submit_urb(acm->ctrlurb, GFP_NOIO); if (rv < 0) - goto err_out; + goto err_out; tasklet_schedule(&acm->urb_task); } diff --git a/drivers/usb/class/cdc-acm.h b/drivers/usb/class/cdc-acm.h index 046e064b033..85c3aaaab7c 100644 --- a/drivers/usb/class/cdc-acm.h +++ b/drivers/usb/class/cdc-acm.h @@ -107,10 +107,14 @@ struct acm { struct list_head filled_read_bufs; int write_used; /* number of non-empty write buffers */ int write_ready; /* write urb is not running */ + int old_ready; + int processing; + int transmitting; spinlock_t write_lock; struct mutex mutex; struct usb_cdc_line_coding line; /* bits, stop, parity */ struct work_struct work; /* work queue entry for line discipline waking up */ + struct work_struct waker; struct tasklet_struct urb_task; /* rx processing */ spinlock_t throttle_lock; /* synchronize throtteling and read callback */ unsigned int ctrlin; /* input control lines (DCD, DSR, RI, break, overruns) */ @@ -123,6 +127,7 @@ struct acm { unsigned char clocal; /* termios CLOCAL */ unsigned int ctrl_caps; /* control capabilities from the class specific header */ unsigned int susp_count; /* number of suspended interfaces */ + struct acm_wb *delayed_wb; /* write queued for a device about to be woken */ }; #define CDC_DATA_INTERFACE_TYPE 0x0a |