6 files changed, 189 insertions, 19 deletions

diff --git a/include/uapi/linux/nfc.h b/include/uapi/linux/nfc.h
index d908d17..0e63cee 100644
--- a/include/uapi/linux/nfc.h
+++ b/include/uapi/linux/nfc.h
@@ -60,6 +60,13 @@
  *      target mode.
  * @NFC_EVENT_DEVICE_DEACTIVATED: event emitted when the adapter is deactivated
  *      from target mode.
+ * @NFC_CMD_LLC_GET_PARAMS: request LTO, RW, and MIUX parameters for a device
+ * @NFC_CMD_LLC_SET_PARAMS: set one or more of LTO, RW, and MIUX parameters for
+ *	a device. LTO must be set before the link is up otherwise -EINPROGRESS
+ *	is returned. RW and MIUX can be set at anytime and will be passed in
+ *	subsequent CONNECT and CC messages.
+ *	If one of the passed parameters is wrong none is set and -EINVAL is
+ *	returned.
  */
 enum nfc_commands {
 	NFC_CMD_UNSPEC,
@@ -77,6 +84,8 @@ enum nfc_commands {
 	NFC_EVENT_TARGET_LOST,
 	NFC_EVENT_TM_ACTIVATED,
 	NFC_EVENT_TM_DEACTIVATED,
+	NFC_CMD_LLC_GET_PARAMS,
+	NFC_CMD_LLC_SET_PARAMS,
 /* private: internal use only */
 	__NFC_CMD_AFTER_LAST
 };
@@ -102,6 +111,9 @@ enum nfc_commands {
  * @NFC_ATTR_RF_MODE: Initiator or target
  * @NFC_ATTR_IM_PROTOCOLS: Initiator mode protocols to poll for
  * @NFC_ATTR_TM_PROTOCOLS: Target mode protocols to listen for
+ * @NFC_ATTR_LLC_PARAM_LTO: Link TimeOut parameter
+ * @NFC_ATTR_LLC_PARAM_RW: Receive Window size parameter
+ * @NFC_ATTR_LLC_PARAM_MIUX: MIU eXtension parameter
  */
 enum nfc_attrs {
 	NFC_ATTR_UNSPEC,
@@ -119,6 +131,9 @@ enum nfc_attrs {
 	NFC_ATTR_DEVICE_POWERED,
 	NFC_ATTR_IM_PROTOCOLS,
 	NFC_ATTR_TM_PROTOCOLS,
+	NFC_ATTR_LLC_PARAM_LTO,
+	NFC_ATTR_LLC_PARAM_RW,
+	NFC_ATTR_LLC_PARAM_MIUX,
 /* private: internal use only */
 	__NFC_ATTR_AFTER_LAST
 };
diff --git a/net/nfc/llcp/commands.c b/net/nfc/llcp/commands.c
index 7941535..ed2d173 100644
--- a/net/nfc/llcp/commands.c
+++ b/net/nfc/llcp/commands.c
@@ -316,8 +316,7 @@ int nfc_llcp_send_connect(struct nfc_llcp_sock *sock)
 	struct sk_buff *skb;
 	u8 *service_name_tlv = NULL, service_name_tlv_length;
 	u8 *miux_tlv = NULL, miux_tlv_length;
-	u8 *rw_tlv = NULL, rw_tlv_length, rw;
-	__be16 miux;
+	u8 *rw_tlv = NULL, rw_tlv_length;
 	int err;
 	u16 size = 0;
 
@@ -335,13 +334,11 @@ int nfc_llcp_send_connect(struct nfc_llcp_sock *sock)
 		size += service_name_tlv_length;
 	}
 
-	miux = cpu_to_be16(LLCP_MAX_MIUX);
-	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
+	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&local->miux, 0,
 				      &miux_tlv_length);
 	size += miux_tlv_length;
 
-	rw = LLCP_MAX_RW;
-	rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
+	rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &local->rw, 0, &rw_tlv_length);
 	size += rw_tlv_length;
 
 	pr_debug("SKB size %d SN length %zu\n", size, sock->service_name_len);
@@ -378,8 +375,7 @@ int nfc_llcp_send_cc(struct nfc_llcp_sock *sock)
 	struct nfc_llcp_local *local;
 	struct sk_buff *skb;
 	u8 *miux_tlv = NULL, miux_tlv_length;
-	u8 *rw_tlv = NULL, rw_tlv_length, rw;
-	__be16 miux;
+	u8 *rw_tlv = NULL, rw_tlv_length;
 	int err;
 	u16 size = 0;
 
@@ -389,13 +385,11 @@ int nfc_llcp_send_cc(struct nfc_llcp_sock *sock)
 	if (local == NULL)
 		return -ENODEV;
 
-	miux = cpu_to_be16(LLCP_MAX_MIUX);
-	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
+	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&local->miux, 0,
 				      &miux_tlv_length);
 	size += miux_tlv_length;
 
-	rw = LLCP_MAX_RW;
-	rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
+	rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &local->rw, 0, &rw_tlv_length);
 	size += rw_tlv_length;
 
 	skb = llcp_allocate_pdu(sock, LLCP_PDU_CC, size);
diff --git a/net/nfc/llcp/llcp.c b/net/nfc/llcp/llcp.c
index 2e23bd3..f680453 100644
--- a/net/nfc/llcp/llcp.c
+++ b/net/nfc/llcp/llcp.c
@@ -467,10 +467,9 @@ static u8 nfc_llcp_reserve_sdp_ssap(struct nfc_llcp_local *local)
 static int nfc_llcp_build_gb(struct nfc_llcp_local *local)
 {
 	u8 *gb_cur, *version_tlv, version, version_length;
-	u8 *lto_tlv, lto, lto_length;
+	u8 *lto_tlv, lto_length;
 	u8 *wks_tlv, wks_length;
 	u8 *miux_tlv, miux_length;
-	__be16 miux;
 	u8 gb_len = 0;
 	int ret = 0;
 
@@ -479,9 +478,7 @@ static int nfc_llcp_build_gb(struct nfc_llcp_local *local)
 					 1, &version_length);
 	gb_len += version_length;
 
-	/* 1500 ms */
-	lto = 150;
-	lto_tlv = nfc_llcp_build_tlv(LLCP_TLV_LTO, &lto, 1, &lto_length);
+	lto_tlv = nfc_llcp_build_tlv(LLCP_TLV_LTO, &local->lto, 1, &lto_length);
 	gb_len += lto_length;
 
 	pr_debug("Local wks 0x%lx\n", local->local_wks);
@@ -489,8 +486,7 @@ static int nfc_llcp_build_gb(struct nfc_llcp_local *local)
 				     &wks_length);
 	gb_len += wks_length;
 
-	miux = cpu_to_be16(LLCP_MAX_MIUX);
-	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
+	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&local->miux, 0,
 				      &miux_length);
 	gb_len += miux_length;
 
@@ -1383,6 +1379,10 @@ int nfc_llcp_register_device(struct nfc_dev *ndev)
 	rwlock_init(&local->connecting_sockets.lock);
 	rwlock_init(&local->raw_sockets.lock);
 
+	local->lto = 150; /* 1500 ms */
+	local->rw = LLCP_MAX_RW;
+	local->miux = cpu_to_be16(LLCP_MAX_MIUX);
+
 	nfc_llcp_build_gb(local);
 
 	local->remote_miu = LLCP_DEFAULT_MIU;
diff --git a/net/nfc/llcp/llcp.h b/net/nfc/llcp/llcp.h
index 276da3a..0d62366 100644
--- a/net/nfc/llcp/llcp.h
+++ b/net/nfc/llcp/llcp.h
@@ -64,6 +64,9 @@ struct nfc_llcp_local {
 	u32 target_idx;
 	u8 rf_mode;
 	u8 comm_mode;
+	u8 lto;
+	u8 rw;
+	__be16 miux;
 	unsigned long local_wks;      /* Well known services */
 	unsigned long local_sdp;      /* Local services  */
 	unsigned long local_sap; /* Local SAPs, not available for discovery */
diff --git a/net/nfc/netlink.c b/net/nfc/netlink.c
index 614cfd0..3568ae1 100644
--- a/net/nfc/netlink.c
+++ b/net/nfc/netlink.c
@@ -29,6 +29,8 @@
 
 #include "nfc.h"
 
+#include "llcp/llcp.h"
+
 static struct genl_multicast_group nfc_genl_event_mcgrp = {
 	.name = NFC_GENL_MCAST_EVENT_NAME,
 };
@@ -716,6 +718,146 @@ static int nfc_genl_dep_link_down(struct sk_buff *skb, struct genl_info *info)
 	return rc;
 }
 
+static int nfc_genl_send_params(struct sk_buff *msg,
+				struct nfc_llcp_local *local,
+				u32 portid, u32 seq)
+{
+	void *hdr;
+
+	hdr = genlmsg_put(msg, portid, seq, &nfc_genl_family, 0,
+			  NFC_CMD_LLC_GET_PARAMS);
+	if (!hdr)
+		return -EMSGSIZE;
+
+	if (nla_put_u32(msg, NFC_ATTR_DEVICE_INDEX, local->dev->idx) ||
+	    nla_put_u8(msg, NFC_ATTR_LLC_PARAM_LTO, local->lto) ||
+	    nla_put_u8(msg, NFC_ATTR_LLC_PARAM_RW, local->rw) ||
+	    nla_put_u16(msg, NFC_ATTR_LLC_PARAM_MIUX, be16_to_cpu(local->miux)))
+		goto nla_put_failure;
+
+	return genlmsg_end(msg, hdr);
+
+nla_put_failure:
+
+	genlmsg_cancel(msg, hdr);
+	return -EMSGSIZE;
+}
+
+static int nfc_genl_llc_get_params(struct sk_buff *skb, struct genl_info *info)
+{
+	struct nfc_dev *dev;
+	struct nfc_llcp_local *local;
+	int rc = 0;
+	struct sk_buff *msg = NULL;
+	u32 idx;
+
+	if (!info->attrs[NFC_ATTR_DEVICE_INDEX])
+		return -EINVAL;
+
+	idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
+
+	dev = nfc_get_device(idx);
+	if (!dev)
+		return -ENODEV;
+
+	device_lock(&dev->dev);
+
+	local = nfc_llcp_find_local(dev);
+	if (!local) {
+		rc = -ENODEV;
+		goto exit;
+	}
+
+	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+	if (!msg) {
+		rc = -ENOMEM;
+		goto exit;
+	}
+
+	rc = nfc_genl_send_params(msg, local, info->snd_portid, info->snd_seq);
+
+exit:
+	device_unlock(&dev->dev);
+
+	nfc_put_device(dev);
+
+	if (rc < 0) {
+		if (msg)
+			nlmsg_free(msg);
+
+		return rc;
+	}
+
+	return genlmsg_reply(msg, info);
+}
+
+static int nfc_genl_llc_set_params(struct sk_buff *skb, struct genl_info *info)
+{
+	struct nfc_dev *dev;
+	struct nfc_llcp_local *local;
+	u8 rw = 0;
+	u16 miux = 0;
+	u32 idx;
+	int rc = 0;
+
+	if (!info->attrs[NFC_ATTR_DEVICE_INDEX] ||
+	    (!info->attrs[NFC_ATTR_LLC_PARAM_LTO] &&
+	     !info->attrs[NFC_ATTR_LLC_PARAM_RW] &&
+	     !info->attrs[NFC_ATTR_LLC_PARAM_MIUX]))
+		return -EINVAL;
+
+	if (info->attrs[NFC_ATTR_LLC_PARAM_RW]) {
+		rw = nla_get_u8(info->attrs[NFC_ATTR_LLC_PARAM_RW]);
+
+		if (rw > LLCP_MAX_RW)
+			return -EINVAL;
+	}
+
+	if (info->attrs[NFC_ATTR_LLC_PARAM_MIUX]) {
+		miux = nla_get_u16(info->attrs[NFC_ATTR_LLC_PARAM_MIUX]);
+
+		if (miux > LLCP_MAX_MIUX)
+			return -EINVAL;
+	}
+
+	idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
+
+	dev = nfc_get_device(idx);
+	if (!dev)
+		return -ENODEV;
+
+	device_lock(&dev->dev);
+
+	local = nfc_llcp_find_local(dev);
+	if (!local) {
+		nfc_put_device(dev);
+		rc = -ENODEV;
+		goto exit;
+	}
+
+	if (info->attrs[NFC_ATTR_LLC_PARAM_LTO]) {
+		if (dev->dep_link_up) {
+			rc = -EINPROGRESS;
+			goto exit;
+		}
+
+		local->lto = nla_get_u8(info->attrs[NFC_ATTR_LLC_PARAM_LTO]);
+	}
+
+	if (info->attrs[NFC_ATTR_LLC_PARAM_RW])
+		local->rw = rw;
+
+	if (info->attrs[NFC_ATTR_LLC_PARAM_MIUX])
+		local->miux = cpu_to_be16(miux);
+
+exit:
+	device_unlock(&dev->dev);
+
+	nfc_put_device(dev);
+
+	return rc;
+}
+
 static struct genl_ops nfc_genl_ops[] = {
 	{
 		.cmd = NFC_CMD_GET_DEVICE,
@@ -760,6 +902,16 @@ static struct genl_ops nfc_genl_ops[] = {
 		.done = nfc_genl_dump_targets_done,
 		.policy = nfc_genl_policy,
 	},
+	{
+		.cmd = NFC_CMD_LLC_GET_PARAMS,
+		.doit = nfc_genl_llc_get_params,
+		.policy = nfc_genl_policy,
+	},
+	{
+		.cmd = NFC_CMD_LLC_SET_PARAMS,
+		.doit = nfc_genl_llc_set_params,
+		.policy = nfc_genl_policy,
+	},
 };
 
 
diff --git a/net/nfc/nfc.h b/net/nfc/nfc.h
index c5e42b79..87d914d 100644
--- a/net/nfc/nfc.h
+++ b/net/nfc/nfc.h
@@ -56,6 +56,7 @@ void nfc_llcp_unregister_device(struct nfc_dev *dev);
 int nfc_llcp_set_remote_gb(struct nfc_dev *dev, u8 *gb, u8 gb_len);
 u8 *nfc_llcp_general_bytes(struct nfc_dev *dev, size_t *general_bytes_len);
 int nfc_llcp_data_received(struct nfc_dev *dev, struct sk_buff *skb);
+struct nfc_llcp_local *nfc_llcp_find_local(struct nfc_dev *dev);
 int __init nfc_llcp_init(void);
 void nfc_llcp_exit(void);
 
@@ -97,6 +98,11 @@ static inline int nfc_llcp_data_received(struct nfc_dev *dev,
 	return 0;
 }
 
+static inline struct nfc_llcp_local *nfc_llcp_find_local(struct nfc_dev *dev)
+{
+	return NULL;
+}
+
 static inline int nfc_llcp_init(void)
 {
 	return 0;