diff options
Diffstat (limited to 'drivers/usb/serial')
| -rw-r--r-- | drivers/usb/serial/sierra.c | 52 |
1 files changed, 35 insertions, 17 deletions
diff --git a/drivers/usb/serial/sierra.c b/drivers/usb/serial/sierra.c index f75688416b6..27f41f95aef 100644 --- a/drivers/usb/serial/sierra.c +++ b/drivers/usb/serial/sierra.c @@ -1,7 +1,10 @@ /* USB Driver for Sierra Wireless - Copyright (C) 2006, 2007, 2008 Kevin Lloyd <klloyd@sierrawireless.com> + Copyright (C) 2006, 2007, 2008 Kevin Lloyd <klloyd@sierrawireless.com>, + + Copyright (C) 2008, 2009 Elina Pasheva, Matthew Safar, Rory Filer + <linux@sierrawireless.com> IMPORTANT DISCLAIMER: This driver is not commercially supported by Sierra Wireless. Use at your own risk. @@ -14,8 +17,8 @@ Whom based his on the Keyspan driver by Hugh Blemings <hugh@blemings.org> */ -#define DRIVER_VERSION "v.1.3.5" -#define DRIVER_AUTHOR "Kevin Lloyd <klloyd@sierrawireless.com>" +#define DRIVER_VERSION "v.1.3.6" +#define DRIVER_AUTHOR "Kevin Lloyd, Elina Pasheva, Matthew Safar, Rory Filer" #define DRIVER_DESC "USB Driver for Sierra Wireless USB modems" #include <linux/kernel.h> @@ -34,6 +37,11 @@ #define N_OUT_URB 64 #define IN_BUFLEN 4096 +#define MAX_TRANSFER (PAGE_SIZE - 512) +/* MAX_TRANSFER is chosen so that the VM is not stressed by + allocations > PAGE_SIZE and the number of packets in a page + is an integer 512 is the largest possible packet on EHCI */ + static int debug; static int nmea; @@ -419,50 +427,58 @@ static int sierra_write(struct tty_struct *tty, struct usb_serial_port *port, unsigned long flags; unsigned char *buffer; struct urb *urb; - int status; + size_t writesize = min((size_t)count, (size_t)MAX_TRANSFER); + int retval = 0; + + /* verify that we actually have some data to write */ + if (count == 0) + return 0; portdata = usb_get_serial_port_data(port); - dev_dbg(&port->dev, "%s: write (%d chars)\n", __func__, count); + dev_dbg(&port->dev, "%s: write (%d bytes)\n", __func__, writesize); spin_lock_irqsave(&portdata->lock, flags); + dev_dbg(&port->dev, "%s - outstanding_urbs: %d\n", __func__, + portdata->outstanding_urbs); if (portdata->outstanding_urbs > N_OUT_URB) { spin_unlock_irqrestore(&portdata->lock, flags); dev_dbg(&port->dev, "%s - write limit hit\n", __func__); return 0; } portdata->outstanding_urbs++; + dev_dbg(&port->dev, "%s - 1, outstanding_urbs: %d\n", __func__, + portdata->outstanding_urbs); spin_unlock_irqrestore(&portdata->lock, flags); - buffer = kmalloc(count, GFP_ATOMIC); + buffer = kmalloc(writesize, GFP_ATOMIC); if (!buffer) { dev_err(&port->dev, "out of memory\n"); - count = -ENOMEM; + retval = -ENOMEM; goto error_no_buffer; } urb = usb_alloc_urb(0, GFP_ATOMIC); if (!urb) { dev_err(&port->dev, "no more free urbs\n"); - count = -ENOMEM; + retval = -ENOMEM; goto error_no_urb; } - memcpy(buffer, buf, count); + memcpy(buffer, buf, writesize); - usb_serial_debug_data(debug, &port->dev, __func__, count, buffer); + usb_serial_debug_data(debug, &port->dev, __func__, writesize, buffer); usb_fill_bulk_urb(urb, serial->dev, usb_sndbulkpipe(serial->dev, port->bulk_out_endpointAddress), - buffer, count, sierra_outdat_callback, port); + buffer, writesize, sierra_outdat_callback, port); /* send it down the pipe */ - status = usb_submit_urb(urb, GFP_ATOMIC); - if (status) { + retval = usb_submit_urb(urb, GFP_ATOMIC); + if (retval) { dev_err(&port->dev, "%s - usb_submit_urb(write bulk) failed " - "with status = %d\n", __func__, status); - count = status; + "with status = %d\n", __func__, retval); goto error; } @@ -470,7 +486,7 @@ static int sierra_write(struct tty_struct *tty, struct usb_serial_port *port, * really free it when it is finished with it */ usb_free_urb(urb); - return count; + return writesize; error: usb_free_urb(urb); error_no_urb: @@ -478,8 +494,10 @@ error_no_urb: error_no_buffer: spin_lock_irqsave(&portdata->lock, flags); --portdata->outstanding_urbs; + dev_dbg(&port->dev, "%s - 2. outstanding_urbs: %d\n", __func__, + portdata->outstanding_urbs); spin_unlock_irqrestore(&portdata->lock, flags); - return count; + return retval; } static void sierra_indat_callback(struct urb *urb) |