src/patches/linux-3.10.y-usbnet_mcs7830_rework_link_detect.patch

   1 From 4e9792dc8ab29175295c79c35f9f6fbd2d453b35 Mon Sep 17 00:00:00 2001
   2 From: Octavian Purdila <octavian.purdila@intel.com>
   3 Date: Mon, 23 Dec 2013 19:06:31 +0200
   4 Subject: [PATCH] usbnet: mcs7830: rework link state detection
   5
   6 Even with the quirks in commit dabdaf0c (mcs7830: Fix link state
   7 detection) there are still spurious link-down events for some chips
   8 where the false link-down events count go over a few hundreds.
   9
  10 This patch takes a more conservative approach and only looks at
  11 link-down events where the link-down state is not combined with other
  12 states (e.g. half/full speed, pending frames in SRAM or TX status
  13 information valid). In all other cases we assume the link is up.
  14
  15 Tested on MCS7830CV-DA (USB ID 9710:7830).
  16
  17 Cc: Ondrej Zary <linux@rainbow-software.org>
  18 Cc: Michael Leun <lkml20120218@newton.leun.net>
  19 Cc: Ming Lei <ming.lei@canonical.com>
  20 Signed-off-by: Octavian Purdila <octavian.purdila@intel.com>
  21 Signed-off-by: David S. Miller <davem@davemloft.net>
  22 ---
  23  drivers/net/usb/mcs7830.c | 19 ++++---------------
  24  1 file changed, 4 insertions(+), 15 deletions(-)
  25
  26 diff --git a/drivers/net/usb/mcs7830.c b/drivers/net/usb/mcs7830.c
  27 index 9237c45..8dd48b5 100644
  28 --- a/drivers/net/usb/mcs7830.c
  29 +++ b/drivers/net/usb/mcs7830.c
  30 @@ -117,7 +117,6 @@ enum {
  31  struct mcs7830_data {
  32         u8 multi_filter[8];
  33         u8 config;
  34 -       u8 link_counter;
  35  };
  36
  37  static const char driver_name[] = "MOSCHIP usb-ethernet driver";
  38 @@ -562,26 +561,16 @@ static void mcs7830_status(struct usbnet *dev, struct urb *urb)
  39  {
  40         u8 *buf = urb->transfer_buffer;
  41         bool link, link_changed;
  42 -       struct mcs7830_data *data = mcs7830_get_data(dev);
  43
  44         if (urb->actual_length < 16)
  45                 return;
  46
  47 -       link = !(buf[1] & 0x20);
  48 +       link = !(buf[1] == 0x20);
  49         link_changed = netif_carrier_ok(dev->net) != link;
  50         if (link_changed) {
  51 -               data->link_counter++;
  52 -               /*
  53 -                  track link state 20 times to guard against erroneous
  54 -                  link state changes reported sometimes by the chip
  55 -                */
  56 -               if (data->link_counter > 20) {
  57 -                       data->link_counter = 0;
  58 -                       usbnet_link_change(dev, link, 0);
  59 -                       netdev_dbg(dev->net, "Link Status is: %d\n", link);
  60 -               }
  61 -       } else
  62 -               data->link_counter = 0;
  63 +               usbnet_link_change(dev, link, 0);
  64 +               netdev_dbg(dev->net, "Link Status is: %d\n", link);
  65 +       }
  66  }
  67
  68  static const struct driver_info moschip_info = {
  69 --
  70 2.0.0
  71