[PATCH 4.9 232/271] net: ethtool: Add back transceiver type

[Greg Kroah-Hartman]

From: Florian Fainelli <f.fainelli@xxxxxxxxx>

commit 19cab8872692960535aa6d12e3a295ac51d1a648 upstream.

Commit 3f1ac7a700d0 ("net: ethtool: add new ETHTOOL_xLINKSETTINGS API")
deprecated the ethtool_cmd::transceiver field, which was fine in
premise, except that the PHY library was actually using it to report the
type of transceiver: internal or external.

Use the first word of the reserved field to put this __u8 transceiver
field back in. It is made read-only, and we don't expect the
ETHTOOL_xLINKSETTINGS API to be doing anything with this anyway, so this
is mostly for the legacy path where we do:

ethtool_get_settings()
-> dev->ethtool_ops->get_link_ksettings()
   -> convert_link_ksettings_to_legacy_settings()

to have no information loss compared to the legacy get_settings API.

Fixes: 3f1ac7a700d0 ("net: ethtool: add new ETHTOOL_xLINKSETTINGS API")
Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 include/uapi/linux/ethtool.h |    6 +++++-
 net/core/ethtool.c           |    2 ++
 2 files changed, 7 insertions(+), 1 deletion(-)

--- a/include/uapi/linux/ethtool.h
+++ b/include/uapi/linux/ethtool.h
@@ -1687,6 +1687,8 @@ enum ethtool_reset_flags {
  *	%ethtool_link_mode_bit_indices for the link modes, and other
  *	link features that the link partner advertised through
  *	autonegotiation; 0 if unknown or not applicable.  Read-only.
+ * @transceiver: Used to distinguish different possible PHY types,
+ *	reported consistently by PHYLIB.  Read-only.
  *
  * If autonegotiation is disabled, the speed and @duplex represent the
  * fixed link mode and are writable if the driver supports multiple
@@ -1738,7 +1740,9 @@ struct ethtool_link_settings {
 	__u8	eth_tp_mdix;
 	__u8	eth_tp_mdix_ctrl;
 	__s8	link_mode_masks_nwords;
-	__u32	reserved[8];
+	__u8	transceiver;
+	__u8	reserved1[3];
+	__u32	reserved[7];
 	__u32	link_mode_masks[0];
 	/* layout of link_mode_masks fields:
 	 * __u32 map_supported[link_mode_masks_nwords];
--- a/net/core/ethtool.c
+++ b/net/core/ethtool.c
@@ -514,6 +514,8 @@ convert_link_ksettings_to_legacy_setting
 		= link_ksettings->base.eth_tp_mdix;
 	legacy_settings->eth_tp_mdix_ctrl
 		= link_ksettings->base.eth_tp_mdix_ctrl;
+	legacy_settings->transceiver
+		= link_ksettings->base.transceiver;
 	return retval;
 }