mcs7830: Implement link state detection

Add .status callback that detects link state changes.
Tested with MCS7832CV-AA chip (9710:7830, identified as rev.C by the driver).
Fixes https://bugzilla.kernel.org/show_bug.cgi?id=28532

Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 23 insertions, 2 deletions

diff --git a/drivers/net/usb/mcs7830.c b/drivers/net/usb/mcs7830.c
index add1064f755d..03c2d8d653df 100644
--- a/drivers/net/usb/mcs7830.c
+++ b/drivers/net/usb/mcs7830.c
@@ -629,11 +629,31 @@ static int mcs7830_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
         return skb->len > 0;
 }
 
+static void mcs7830_status(struct usbnet *dev, struct urb *urb)
+{
+        u8 *buf = urb->transfer_buffer;
+        bool link;
+
+        if (urb->actual_length < 16)
+                return;
+
+        link = !(buf[1] & 0x20);
+        if (netif_carrier_ok(dev->net) != link) {
+                if (link) {
+                        netif_carrier_on(dev->net);
+                        usbnet_defer_kevent(dev, EVENT_LINK_RESET);
+                } else
+                        netif_carrier_off(dev->net);
+                netdev_dbg(dev->net, "Link Status is: %d\n", link);
+        }
+}
+
 static const struct driver_info moschip_info = {
         .description    = "MOSCHIP 7830/7832/7730 usb-NET adapter",
         .bind           = mcs7830_bind,
         .rx_fixup       = mcs7830_rx_fixup,
-        .flags          = FLAG_ETHER,
+        .flags          = FLAG_ETHER | FLAG_LINK_INTR,
+        .status         = mcs7830_status,
         .in             = 1,
         .out            = 2,
 };
@@ -642,7 +662,8 @@ static const struct driver_info sitecom_info = {
         .description    = "Sitecom LN-30 usb-NET adapter",
         .bind           = mcs7830_bind,
         .rx_fixup       = mcs7830_rx_fixup,
-        .flags          = FLAG_ETHER,
+        .flags          = FLAG_ETHER | FLAG_LINK_INTR,
+        .status         = mcs7830_status,
         .in             = 1,
         .out            = 2,
 };