diff options
| -rw-r--r-- | drivers/usb/class/cdc-acm.c | 112 | ||||
| -rw-r--r-- | drivers/usb/class/cdc-acm.h | 3 |
2 files changed, 86 insertions, 29 deletions
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index cdabe76960bc..eb854dd4ed5b 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -36,6 +36,7 @@ #include <linux/errno.h> #include <linux/init.h> #include <linux/slab.h> +#include <linux/log2.h> #include <linux/tty.h> #include <linux/serial.h> #include <linux/tty_driver.h> @@ -283,39 +284,13 @@ static DEVICE_ATTR(iCountryCodeRelDate, S_IRUGO, show_country_rel_date, NULL); * Interrupt handlers for various ACM device responses */ -/* control interface reports status changes with "interrupt" transfers */ -static void acm_ctrl_irq(struct urb *urb) +static void acm_process_notification(struct acm *acm, unsigned char *buf) { - struct acm *acm = urb->context; - struct usb_cdc_notification *dr = urb->transfer_buffer; - unsigned char *data; int newctrl; int difference; - int retval; - int status = urb->status; - - switch (status) { - case 0: - /* success */ - break; - case -ECONNRESET: - case -ENOENT: - case -ESHUTDOWN: - /* this urb is terminated, clean up */ - dev_dbg(&acm->control->dev, - "%s - urb shutting down with status: %d\n", - __func__, status); - return; - default: - dev_dbg(&acm->control->dev, - "%s - nonzero urb status received: %d\n", - __func__, status); - goto exit; - } + struct usb_cdc_notification *dr = (struct usb_cdc_notification *)buf; + unsigned char *data = buf + sizeof(struct usb_cdc_notification); - usb_mark_last_busy(acm->dev); - - data = (unsigned char *)(dr + 1); switch (dr->bNotificationType) { case USB_CDC_NOTIFY_NETWORK_CONNECTION: dev_dbg(&acm->control->dev, @@ -368,9 +343,83 @@ static void acm_ctrl_irq(struct urb *urb) "%s - unknown notification %d received: index %d len %d\n", __func__, dr->bNotificationType, dr->wIndex, dr->wLength); + } +} +/* control interface reports status changes with "interrupt" transfers */ +static void acm_ctrl_irq(struct urb *urb) +{ + struct acm *acm = urb->context; + struct usb_cdc_notification *dr = urb->transfer_buffer; + unsigned int current_size = urb->actual_length; + unsigned int expected_size, copy_size, alloc_size; + int retval; + int status = urb->status; + + switch (status) { + case 0: + /* success */ break; + case -ECONNRESET: + case -ENOENT: + case -ESHUTDOWN: + /* this urb is terminated, clean up */ + acm->nb_index = 0; + dev_dbg(&acm->control->dev, + "%s - urb shutting down with status: %d\n", + __func__, status); + return; + default: + dev_dbg(&acm->control->dev, + "%s - nonzero urb status received: %d\n", + __func__, status); + goto exit; + } + + usb_mark_last_busy(acm->dev); + + if (acm->nb_index) + dr = (struct usb_cdc_notification *)acm->notification_buffer; + + /* size = notification-header + (optional) data */ + expected_size = sizeof(struct usb_cdc_notification) + + le16_to_cpu(dr->wLength); + + if (current_size < expected_size) { + /* notification is transmitted fragmented, reassemble */ + if (acm->nb_size < expected_size) { + if (acm->nb_size) { + kfree(acm->notification_buffer); + acm->nb_size = 0; + } + alloc_size = roundup_pow_of_two(expected_size); + /* + * kmalloc ensures a valid notification_buffer after a + * use of kfree in case the previous allocation was too + * small. Final freeing is done on disconnect. + */ + acm->notification_buffer = + kmalloc(alloc_size, GFP_ATOMIC); + if (!acm->notification_buffer) + goto exit; + acm->nb_size = alloc_size; + } + + copy_size = min(current_size, + expected_size - acm->nb_index); + + memcpy(&acm->notification_buffer[acm->nb_index], + urb->transfer_buffer, copy_size); + acm->nb_index += copy_size; + current_size = acm->nb_index; } + + if (current_size >= expected_size) { + /* notification complete */ + acm_process_notification(acm, (unsigned char *)dr); + acm->nb_index = 0; + } + exit: retval = usb_submit_urb(urb, GFP_ATOMIC); if (retval && retval != -EPERM) @@ -1483,6 +1532,9 @@ skip_countries: epctrl->bInterval ? epctrl->bInterval : 16); acm->ctrlurb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; acm->ctrlurb->transfer_dma = acm->ctrl_dma; + acm->notification_buffer = NULL; + acm->nb_index = 0; + acm->nb_size = 0; dev_info(&intf->dev, "ttyACM%d: USB ACM device\n", minor); @@ -1575,6 +1627,8 @@ static void acm_disconnect(struct usb_interface *intf) usb_free_coherent(acm->dev, acm->ctrlsize, acm->ctrl_buffer, acm->ctrl_dma); acm_read_buffers_free(acm); + kfree(acm->notification_buffer); + if (!acm->combined_interfaces) usb_driver_release_interface(&acm_driver, intf == acm->control ? acm->data : acm->control); diff --git a/drivers/usb/class/cdc-acm.h b/drivers/usb/class/cdc-acm.h index c980f11cdf56..b51913836409 100644 --- a/drivers/usb/class/cdc-acm.h +++ b/drivers/usb/class/cdc-acm.h @@ -98,6 +98,9 @@ struct acm { struct acm_wb *putbuffer; /* for acm_tty_put_char() */ int rx_buflimit; spinlock_t read_lock; + u8 *notification_buffer; /* to reassemble fragmented notifications */ + unsigned int nb_index; + unsigned int nb_size; int write_used; /* number of non-empty write buffers */ int transmitting; spinlock_t write_lock; |