[RFC,ethtool-next,6/6] ethtool: Add ability to reset transceiver modules

diff --git a/ethtool.8.in b/ethtool.8.in
index f9d901cdefca..9953289758d4 100644
--- a/ethtool.8.in
+++ b/ethtool.8.in
@@ -482,6 +482,9 @@  ethtool \- query or control network driver and hardware settings
 .B ethtool \-\-set\-module
 .I devname
 .B2 low-power on off
+.HP
+.B ethtool \-\-reset\-module
+.I devname
 .
 .\" Adjust lines (i.e. full justification) and hyphenate.
 .ad
@@ -1473,6 +1476,12 @@  Set the transceiver module's parameters.
 .A2 low-power on off
 Enable / disable forcing of low power mode by the host.
 .RE
+.TP
+.B \-\-reset\-module
+Reset the transceiver module to its initial state. Reset is performed by either
+asserting the relevant hardware signal or by writing to the module's reset bit
+in its EEPROM.
+.RE
 .SH BUGS
 Not supported (in part or whole) on all network drivers.
 .SH AUTHOR
diff --git a/ethtool.c b/ethtool.c
index 89ff03b18fbf..0ce574b62692 100644
--- a/ethtool.c
+++ b/ethtool.c
@@ -6031,6 +6031,11 @@  static const struct option args[] = {
 		.help	= "Set transceiver module settings",
 		.xhelp	= "		[ low-power on|off ]\n"
 	},
+	{
+		.opts	= "--reset-module",
+		.nlfunc	= nl_reset_module,
+		.help	= "Reset transceiver module",
+	},
 	{
 		.opts	= "-h|--help",
 		.no_dev	= true,
diff --git a/netlink/desc-ethtool.c b/netlink/desc-ethtool.c
index 3fb31b28f288..fce065fce3ae 100644
--- a/netlink/desc-ethtool.c
+++ b/netlink/desc-ethtool.c
@@ -416,6 +416,7 @@  const struct pretty_nlmsg_desc ethnl_umsg_desc[] = {
 	NLMSG_DESC(ETHTOOL_MSG_MODULE_EEPROM_GET, module_eeprom),
 	NLMSG_DESC(ETHTOOL_MSG_MODULE_GET, module),
 	NLMSG_DESC(ETHTOOL_MSG_MODULE_SET, module),
+	NLMSG_DESC(ETHTOOL_MSG_MODULE_RESET_ACT, module),
 };
 
 const unsigned int ethnl_umsg_n_desc = ARRAY_SIZE(ethnl_umsg_desc);
@@ -457,6 +458,7 @@  const struct pretty_nlmsg_desc ethnl_kmsg_desc[] = {
 	NLMSG_DESC(ETHTOOL_MSG_MODULE_EEPROM_GET_REPLY, module_eeprom),
 	NLMSG_DESC(ETHTOOL_MSG_MODULE_GET_REPLY, module),
 	NLMSG_DESC(ETHTOOL_MSG_MODULE_NTF, module),
+	NLMSG_DESC(ETHTOOL_MSG_MODULE_RESET_NTF, module),
 };
 
 const unsigned int ethnl_kmsg_n_desc = ARRAY_SIZE(ethnl_kmsg_desc);
diff --git a/netlink/extapi.h b/netlink/extapi.h
index 2ab4c6bc2f8d..6c294d9058ce 100644
--- a/netlink/extapi.h
+++ b/netlink/extapi.h
@@ -45,6 +45,7 @@  bool nl_gstats_chk(struct cmd_context *ctx);
 int nl_gstats(struct cmd_context *ctx);
 int nl_gmodule(struct cmd_context *ctx);
 int nl_smodule(struct cmd_context *ctx);
+int nl_reset_module(struct cmd_context *ctx);
 int nl_monitor(struct cmd_context *ctx);
 int nl_getmodule(struct cmd_context *ctx);
 
@@ -103,6 +104,7 @@  static inline void nl_monitor_usage(void)
 #define nl_getmodule		NULL
 #define nl_gmodule		NULL
 #define nl_smodule		NULL
+#define nl_reset_module		NULL
 
 #endif /* ETHTOOL_ENABLE_NETLINK */
 
diff --git a/netlink/module.c b/netlink/module.c
index 59a149075f0f..ae5423ff92f6 100644
--- a/netlink/module.c
+++ b/netlink/module.c
@@ -137,3 +137,55 @@  int nl_smodule(struct cmd_context *ctx)
 	else
 		return nlctx->exit_code ?: 83;
 }
+
+/* MODULE_RESET_ACT */
+
+int module_reset_ntf_cb(const struct nlmsghdr *nlhdr, void *data)
+{
+	const struct nlattr *tb[ETHTOOL_A_MODULE_MAX + 1] = {};
+	struct nl_context *nlctx = data;
+	DECLARE_ATTR_TB_INFO(tb);
+	int ret;
+
+	ret = mnl_attr_parse(nlhdr, GENL_HDRLEN, attr_cb, &tb_info);
+	if (ret < 0)
+		return MNL_CB_OK;
+	nlctx->devname = get_dev_name(tb[ETHTOOL_A_MODULE_HEADER]);
+	if (!dev_ok(nlctx))
+		return MNL_CB_OK;
+
+	printf("\nModule reset done for %s\n", nlctx->devname);
+
+	return MNL_CB_OK;
+}
+
+int nl_reset_module(struct cmd_context *ctx)
+{
+	struct nl_context *nlctx = ctx->nlctx;
+	struct nl_msg_buff *msgbuff;
+	struct nl_socket *nlsk;
+	int ret;
+
+	if (netlink_cmd_check(ctx, ETHTOOL_MSG_MODULE_RESET_ACT, false))
+		return -EOPNOTSUPP;
+
+	nlsk = nlctx->ethnl_socket;
+	msgbuff = &nlsk->msgbuff;
+
+	ret = msg_init(nlctx, msgbuff, ETHTOOL_MSG_MODULE_RESET_ACT,
+		       NLM_F_REQUEST | NLM_F_ACK);
+	if (ret < 0)
+		return 2;
+	if (ethnla_fill_header(msgbuff, ETHTOOL_A_MODULE_HEADER,
+			       ctx->devname, 0))
+		return -EMSGSIZE;
+
+	ret = nlsock_sendmsg(nlsk, NULL);
+	if (ret < 0)
+		return 83;
+	ret = nlsock_process_reply(nlsk, nomsg_reply_cb, nlctx);
+	if (ret == 0)
+		return 0;
+	else
+		return nlctx->exit_code ?: 83;
+}
diff --git a/netlink/monitor.c b/netlink/monitor.c
index d631907817e2..e850c3d72108 100644
--- a/netlink/monitor.c
+++ b/netlink/monitor.c
@@ -75,6 +75,10 @@  static struct {
 		.cmd	= ETHTOOL_MSG_MODULE_NTF,
 		.cb	= module_reply_cb,
 	},
+	{
+		.cmd	= ETHTOOL_MSG_MODULE_RESET_NTF,
+		.cb	= module_reset_ntf_cb,
+	},
 };
 
 static void clear_filter(struct nl_context *nlctx)
diff --git a/netlink/netlink.h b/netlink/netlink.h
index f43c1bff6a58..1e49d7f2bab3 100644
--- a/netlink/netlink.h
+++ b/netlink/netlink.h
@@ -92,6 +92,7 @@  int cable_test_tdr_reply_cb(const struct nlmsghdr *nlhdr, void *data);
 int cable_test_tdr_ntf_cb(const struct nlmsghdr *nlhdr, void *data);
 int fec_reply_cb(const struct nlmsghdr *nlhdr, void *data);
 int module_reply_cb(const struct nlmsghdr *nlhdr, void *data);
+int module_reset_ntf_cb(const struct nlmsghdr *nlhdr, void *data);
 
 /* dump helpers */
 
diff --git a/shell-completion/bash/ethtool b/shell-completion/bash/ethtool
index 5db3b4f50232..8818985f1cd9 100644
--- a/shell-completion/bash/ethtool
+++ b/shell-completion/bash/ethtool
@@ -1211,6 +1211,7 @@  _ethtool()
 		[--test]=test
 		[--set-module]=set_module
 		[--show-module]=devname
+		[--reset-module]=devname
 	)
 	local -A other_funcs=(
 		[--config-ntuple]=config_nfc