NFC: st21nfcb: Add support for secure element

The st21nfcb chipset has 3 SWP (Single Wire Protocol) lines and
supports up to 3 secure elements (UICC/eSE and µSD in the future).

Some st21nfcb firmware does not support the nci command
nci_nfcee_mode_set(NCI_NFCEE_DISABLE). For this reason, we assume
2 secures elements are always present (UICC and eSE).
They will be added to the SE list once successfully activated and
they will be available only after running through enable_se
handler or when the poll in listen mode is started.

During initialization, the white_list will be always set assuming
both UICC & eSE are present.

On eSE activation, the ATR bytes are fetched to build the command
exchange timeout.

The se_io hook will allow to transfer data over SWP. 2 kind of
events may appear data is sent over:
- ST21NFCB_EVT_TRANSMIT_DATA when receiving an apdu answer
- ST21NFCB_EVT_WTX_REQUEST when the secure element needs more time
  than expected to process a command. If this timeout expires, we
  send a software reset, and then a hardware one if it still fails.

Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

5 files changed, 746 insertions, 2 deletions

diff --git a/drivers/nfc/st21nfcb/Makefile b/drivers/nfc/st21nfcb/Makefile
index f4d835dd15f2..ce659a9e5a1a 100644
--- a/drivers/nfc/st21nfcb/Makefile
+++ b/drivers/nfc/st21nfcb/Makefile
@@ -2,7 +2,7 @@
 # Makefile for ST21NFCB NCI based NFC driver
 #
 
-st21nfcb_nci-objs = ndlc.o st21nfcb.o
+st21nfcb_nci-objs = ndlc.o st21nfcb.o st21nfcb_se.o
 obj-$(CONFIG_NFC_ST21NFCB)     += st21nfcb_nci.o
 
 st21nfcb_i2c-objs = i2c.o
diff --git a/drivers/nfc/st21nfcb/st21nfcb.c b/drivers/nfc/st21nfcb/st21nfcb.c
index ea63d5877831..ca9871ab3fb3 100644
--- a/drivers/nfc/st21nfcb/st21nfcb.c
+++ b/drivers/nfc/st21nfcb/st21nfcb.c
@@ -22,6 +22,7 @@
 #include <net/nfc/nci_core.h>
 
 #include "st21nfcb.h"
+#include "st21nfcb_se.h"
 
 #define DRIVER_DESC "NCI NFC driver for ST21NFCB"
 
@@ -78,6 +79,13 @@ static struct nci_ops st21nfcb_nci_ops = {
         .close = st21nfcb_nci_close,
         .send = st21nfcb_nci_send,
         .get_rfprotocol = st21nfcb_nci_get_rfprotocol,
+        .discover_se = st21nfcb_nci_discover_se,
+        .enable_se = st21nfcb_nci_enable_se,
+        .disable_se = st21nfcb_nci_disable_se,
+        .se_io = st21nfcb_nci_se_io,
+        .hci_load_session = st21nfcb_hci_load_session,
+        .hci_event_received = st21nfcb_hci_event_received,
+        .hci_cmd_received = st21nfcb_hci_cmd_received,
 };
 
 int st21nfcb_nci_probe(struct llt_ndlc *ndlc, int phy_headroom,
@@ -114,9 +122,10 @@ int st21nfcb_nci_probe(struct llt_ndlc *ndlc, int phy_headroom,
         if (r) {
                 pr_err("Cannot register nfc device to nci core\n");
                 nci_free_device(ndlc->ndev);
+                return r;
         }
 
-        return r;
+        return st21nfcb_se_init(ndlc->ndev);
 }
 EXPORT_SYMBOL_GPL(st21nfcb_nci_probe);
 
diff --git a/drivers/nfc/st21nfcb/st21nfcb.h b/drivers/nfc/st21nfcb/st21nfcb.h
index ea58a56ad794..5ef8a58c9839 100644
--- a/drivers/nfc/st21nfcb/st21nfcb.h
+++ b/drivers/nfc/st21nfcb/st21nfcb.h
@@ -19,6 +19,7 @@
 #ifndef __LOCAL_ST21NFCB_H_
 #define __LOCAL_ST21NFCB_H_
 
+#include "st21nfcb_se.h"
 #include "ndlc.h"
 
 /* Define private flags: */
@@ -27,6 +28,7 @@
 struct st21nfcb_nci_info {
         struct llt_ndlc *ndlc;
         unsigned long flags;
+        struct st21nfcb_se_info se_info;
 };
 
 void st21nfcb_nci_remove(struct nci_dev *ndev);
diff --git a/drivers/nfc/st21nfcb/st21nfcb_se.c b/drivers/nfc/st21nfcb/st21nfcb_se.c
new file mode 100644
index 000000000000..f7977a47c047
--- /dev/null
+++ b/drivers/nfc/st21nfcb/st21nfcb_se.c
@@ -0,0 +1,672 @@
+/*
+ * NCI based Driver for STMicroelectronics NFC Chip
+ *
+ * Copyright (C) 2014  STMicroelectronics SAS. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/module.h>
+#include <linux/nfc.h>
+#include <linux/delay.h>
+#include <net/nfc/nci.h>
+#include <net/nfc/nci_core.h>
+
+#include "st21nfcb.h"
+#include "st21nfcb_se.h"
+
+struct st21nfcb_pipe_info {
+        u8 pipe_state;
+        u8 src_host_id;
+        u8 src_gate_id;
+        u8 dst_host_id;
+        u8 dst_gate_id;
+} __packed;
+
+/* Hosts */
+#define ST21NFCB_HOST_CONTROLLER_ID     0x00
+#define ST21NFCB_TERMINAL_HOST_ID       0x01
+#define ST21NFCB_UICC_HOST_ID           0x02
+#define ST21NFCB_ESE_HOST_ID            0xc0
+
+/* Gates */
+#define ST21NFCB_DEVICE_MGNT_GATE       0x01
+#define ST21NFCB_APDU_READER_GATE       0xf0
+#define ST21NFCB_CONNECTIVITY_GATE      0x41
+
+/* Pipes */
+#define ST21NFCB_DEVICE_MGNT_PIPE               0x02
+
+/* Connectivity pipe only */
+#define ST21NFCB_SE_COUNT_PIPE_UICC             0x01
+/* Connectivity + APDU Reader pipe */
+#define ST21NFCB_SE_COUNT_PIPE_EMBEDDED         0x02
+
+#define ST21NFCB_SE_TO_HOT_PLUG                 1000 /* msecs */
+#define ST21NFCB_SE_TO_PIPES                    2000
+
+#define ST21NFCB_EVT_HOT_PLUG_IS_INHIBITED(x)   (x->data[0] & 0x80)
+
+#define NCI_HCI_APDU_PARAM_ATR                     0x01
+#define NCI_HCI_ADMIN_PARAM_SESSION_IDENTITY       0x01
+#define NCI_HCI_ADMIN_PARAM_WHITELIST              0x03
+#define NCI_HCI_ADMIN_PARAM_HOST_LIST              0x04
+
+#define ST21NFCB_EVT_SE_HARD_RESET              0x20
+#define ST21NFCB_EVT_TRANSMIT_DATA              0x10
+#define ST21NFCB_EVT_WTX_REQUEST                0x11
+#define ST21NFCB_EVT_SE_SOFT_RESET              0x11
+#define ST21NFCB_EVT_SE_END_OF_APDU_TRANSFER    0x21
+#define ST21NFCB_EVT_HOT_PLUG                   0x03
+
+#define ST21NFCB_SE_MODE_OFF                    0x00
+#define ST21NFCB_SE_MODE_ON                     0x01
+
+#define ST21NFCB_EVT_CONNECTIVITY       0x10
+#define ST21NFCB_EVT_TRANSACTION        0x12
+
+#define ST21NFCB_DM_GETINFO             0x13
+#define ST21NFCB_DM_GETINFO_PIPE_LIST   0x02
+#define ST21NFCB_DM_GETINFO_PIPE_INFO   0x01
+#define ST21NFCB_DM_PIPE_CREATED        0x02
+#define ST21NFCB_DM_PIPE_OPEN           0x04
+#define ST21NFCB_DM_RF_ACTIVE           0x80
+#define ST21NFCB_DM_DISCONNECT          0x30
+
+#define ST21NFCB_DM_IS_PIPE_OPEN(p) \
+        ((p & 0x0f) == (ST21NFCB_DM_PIPE_CREATED | ST21NFCB_DM_PIPE_OPEN))
+
+#define ST21NFCB_ATR_DEFAULT_BWI        0x04
+
+/*
+ * WT = 2^BWI/10[s], convert into msecs and add a secure
+ * room by increasing by 2 this timeout
+ */
+#define ST21NFCB_BWI_TO_TIMEOUT(x)      ((1 << x) * 200)
+#define ST21NFCB_ATR_GET_Y_FROM_TD(x)   (x >> 4)
+
+/* If TA is present bit 0 is set */
+#define ST21NFCB_ATR_TA_PRESENT(x) (x & 0x01)
+/* If TB is present bit 1 is set */
+#define ST21NFCB_ATR_TB_PRESENT(x) (x & 0x02)
+
+#define ST21NFCB_NUM_DEVICES           256
+
+static DECLARE_BITMAP(dev_mask, ST21NFCB_NUM_DEVICES);
+
+/* Here are the mandatory pipe for st21nfcb */
+static struct nci_hci_gate st21nfcb_gates[] = {
+        {NCI_HCI_ADMIN_GATE, NCI_HCI_ADMIN_PIPE,
+                                        ST21NFCB_HOST_CONTROLLER_ID},
+        {NCI_HCI_LINK_MGMT_GATE, NCI_HCI_LINK_MGMT_PIPE,
+                                        ST21NFCB_HOST_CONTROLLER_ID},
+        {ST21NFCB_DEVICE_MGNT_GATE, ST21NFCB_DEVICE_MGNT_PIPE,
+                                        ST21NFCB_HOST_CONTROLLER_ID},
+
+        /* Secure element pipes are created by secure element host */
+        {ST21NFCB_CONNECTIVITY_GATE, NCI_HCI_DO_NOT_OPEN_PIPE,
+                                        ST21NFCB_HOST_CONTROLLER_ID},
+        {ST21NFCB_APDU_READER_GATE, NCI_HCI_DO_NOT_OPEN_PIPE,
+                                        ST21NFCB_HOST_CONTROLLER_ID},
+};
+
+static u8 st21nfcb_se_get_bwi(struct nci_dev *ndev)
+{
+        int i;
+        u8 td;
+        struct st21nfcb_nci_info *info = nci_get_drvdata(ndev);
+
+        /* Bits 8 to 5 of the first TB for T=1 encode BWI from zero to nine */
+        for (i = 1; i < ST21NFCB_ESE_MAX_LENGTH; i++) {
+                td = ST21NFCB_ATR_GET_Y_FROM_TD(info->se_info.atr[i]);
+                if (ST21NFCB_ATR_TA_PRESENT(td))
+                        i++;
+                if (ST21NFCB_ATR_TB_PRESENT(td)) {
+                        i++;
+                        return info->se_info.atr[i] >> 4;
+                }
+        }
+        return ST21NFCB_ATR_DEFAULT_BWI;
+}
+
+static void st21nfcb_se_get_atr(struct nci_dev *ndev)
+{
+        struct st21nfcb_nci_info *info = nci_get_drvdata(ndev);
+        int r;
+        struct sk_buff *skb;
+
+        r = nci_hci_get_param(ndev, ST21NFCB_APDU_READER_GATE,
+                                NCI_HCI_APDU_PARAM_ATR, &skb);
+        if (r < 0)
+                return;
+
+        if (skb->len <= ST21NFCB_ESE_MAX_LENGTH) {
+                memcpy(info->se_info.atr, skb->data, skb->len);
+
+                info->se_info.wt_timeout =
+                        ST21NFCB_BWI_TO_TIMEOUT(st21nfcb_se_get_bwi(ndev));
+        }
+        kfree_skb(skb);
+}
+
+int st21nfcb_hci_load_session(struct nci_dev *ndev)
+{
+        int i, j, r;
+        struct sk_buff *skb_pipe_list, *skb_pipe_info;
+        struct st21nfcb_pipe_info *dm_pipe_info;
+        u8 pipe_list[] = { ST21NFCB_DM_GETINFO_PIPE_LIST,
+                        ST21NFCB_TERMINAL_HOST_ID};
+        u8 pipe_info[] = { ST21NFCB_DM_GETINFO_PIPE_INFO,
+                        ST21NFCB_TERMINAL_HOST_ID, 0};
+
+        /* On ST21NFCB device pipes number are dynamics
+         * If pipes are already created, hci_dev_up will fail.
+         * Doing a clear all pipe is a bad idea because:
+         * - It does useless EEPROM cycling
+         * - It might cause issue for secure elements support
+         * (such as removing connectivity or APDU reader pipe)
+         * A better approach on ST21NFCB is to:
+         * - get a pipe list for each host.
+         * (eg: ST21NFCB_HOST_CONTROLLER_ID for now).
+         * (TODO Later on UICC HOST and eSE HOST)
+         * - get pipe information
+         * - match retrieved pipe list in st21nfcb_gates
+         * ST21NFCB_DEVICE_MGNT_GATE is a proprietary gate
+         * with ST21NFCB_DEVICE_MGNT_PIPE.
+         * Pipe can be closed and need to be open.
+         */
+        r = nci_hci_connect_gate(ndev, ST21NFCB_HOST_CONTROLLER_ID,
+                                ST21NFCB_DEVICE_MGNT_GATE,
+                                ST21NFCB_DEVICE_MGNT_PIPE);
+        if (r < 0)
+                goto free_info;
+
+        /* Get pipe list */
+        r = nci_hci_send_cmd(ndev, ST21NFCB_DEVICE_MGNT_GATE,
+                        ST21NFCB_DM_GETINFO, pipe_list, sizeof(pipe_list),
+                        &skb_pipe_list);
+        if (r < 0)
+                goto free_info;
+
+        /* Complete the existing gate_pipe table */
+        for (i = 0; i < skb_pipe_list->len; i++) {
+                pipe_info[2] = skb_pipe_list->data[i];
+                r = nci_hci_send_cmd(ndev, ST21NFCB_DEVICE_MGNT_GATE,
+                                        ST21NFCB_DM_GETINFO, pipe_info,
+                                        sizeof(pipe_info), &skb_pipe_info);
+
+                if (r)
+                        continue;
+
+                /*
+                 * Match pipe ID and gate ID
+                 * Output format from ST21NFC_DM_GETINFO is:
+                 * - pipe state (1byte)
+                 * - source hid (1byte)
+                 * - source gid (1byte)
+                 * - destination hid (1byte)
+                 * - destination gid (1byte)
+                 */
+                dm_pipe_info = (struct st21nfcb_pipe_info *)skb_pipe_info->data;
+                if (dm_pipe_info->dst_gate_id == ST21NFCB_APDU_READER_GATE &&
+                    dm_pipe_info->src_host_id != ST21NFCB_ESE_HOST_ID) {
+                        pr_err("Unexpected apdu_reader pipe on host %x\n",
+                               dm_pipe_info->src_host_id);
+                        continue;
+                }
+
+                for (j = 0; (j < ARRAY_SIZE(st21nfcb_gates)) &&
+                     (st21nfcb_gates[j].gate != dm_pipe_info->dst_gate_id); j++)
+                        ;
+
+                if (j < ARRAY_SIZE(st21nfcb_gates) &&
+                    st21nfcb_gates[j].gate == dm_pipe_info->dst_gate_id &&
+                    ST21NFCB_DM_IS_PIPE_OPEN(dm_pipe_info->pipe_state)) {
+                        st21nfcb_gates[j].pipe = pipe_info[2];
+
+                        ndev->hci_dev->gate2pipe[st21nfcb_gates[j].gate] =
+                                                st21nfcb_gates[j].pipe;
+                        ndev->hci_dev->pipes[st21nfcb_gates[j].pipe].gate =
+                                                st21nfcb_gates[j].gate;
+                        ndev->hci_dev->pipes[st21nfcb_gates[j].pipe].host =
+                                                dm_pipe_info->src_host_id;
+                }
+        }
+
+        memcpy(ndev->hci_dev->init_data.gates, st21nfcb_gates,
+               sizeof(st21nfcb_gates));
+
+free_info:
+        kfree_skb(skb_pipe_info);
+        kfree_skb(skb_pipe_list);
+        return r;
+}
+EXPORT_SYMBOL_GPL(st21nfcb_hci_load_session);
+
+static void st21nfcb_hci_admin_event_received(struct nci_dev *ndev,
+                                              u8 event, struct sk_buff *skb)
+{
+        struct st21nfcb_nci_info *info = nci_get_drvdata(ndev);
+
+        switch (event) {
+        case ST21NFCB_EVT_HOT_PLUG:
+                if (info->se_info.se_active) {
+                        if (!ST21NFCB_EVT_HOT_PLUG_IS_INHIBITED(skb)) {
+                                del_timer_sync(&info->se_info.se_active_timer);
+                                info->se_info.se_active = false;
+                                complete(&info->se_info.req_completion);
+                        } else {
+                                mod_timer(&info->se_info.se_active_timer,
+                                      jiffies +
+                                      msecs_to_jiffies(ST21NFCB_SE_TO_PIPES));
+                        }
+                }
+        break;
+        }
+}
+
+static int st21nfcb_hci_apdu_reader_event_received(struct nci_dev *ndev,
+                                                   u8 event,
+                                                   struct sk_buff *skb)
+{
+        int r = 0;
+        struct st21nfcb_nci_info *info = nci_get_drvdata(ndev);
+
+        pr_debug("apdu reader gate event: %x\n", event);
+
+        switch (event) {
+        case ST21NFCB_EVT_TRANSMIT_DATA:
+                del_timer_sync(&info->se_info.bwi_timer);
+                info->se_info.bwi_active = false;
+                info->se_info.cb(info->se_info.cb_context,
+                                 skb->data, skb->len, 0);
+        break;
+        case ST21NFCB_EVT_WTX_REQUEST:
+                mod_timer(&info->se_info.bwi_timer, jiffies +
+                          msecs_to_jiffies(info->se_info.wt_timeout));
+        break;
+        }
+
+        kfree_skb(skb);
+        return r;
+}
+
+/*
+ * Returns:
+ * <= 0: driver handled the event, skb consumed
+ *    1: driver does not handle the event, please do standard processing
+ */
+static int st21nfcb_hci_connectivity_event_received(struct nci_dev *ndev,
+                                                u8 host, u8 event,
+                                                struct sk_buff *skb)
+{
+        int r = 0;
+
+        pr_debug("connectivity gate event: %x\n", event);
+
+        switch (event) {
+        case ST21NFCB_EVT_CONNECTIVITY:
+        break;
+        case ST21NFCB_EVT_TRANSACTION:
+        break;
+        default:
+                return 1;
+        }
+        kfree_skb(skb);
+        return r;
+}
+
+void st21nfcb_hci_event_received(struct nci_dev *ndev, u8 pipe,
+                                 u8 event, struct sk_buff *skb)
+{
+        u8 gate = ndev->hci_dev->pipes[pipe].gate;
+        u8 host = ndev->hci_dev->pipes[pipe].host;
+
+        switch (gate) {
+        case NCI_HCI_ADMIN_GATE:
+                st21nfcb_hci_admin_event_received(ndev, event, skb);
+        break;
+        case ST21NFCB_APDU_READER_GATE:
+                st21nfcb_hci_apdu_reader_event_received(ndev, event, skb);
+        break;
+        case ST21NFCB_CONNECTIVITY_GATE:
+                st21nfcb_hci_connectivity_event_received(ndev, host, event,
+                                                         skb);
+        break;
+        }
+}
+EXPORT_SYMBOL_GPL(st21nfcb_hci_event_received);
+
+
+void st21nfcb_hci_cmd_received(struct nci_dev *ndev, u8 pipe, u8 cmd,
+                               struct sk_buff *skb)
+{
+        struct st21nfcb_nci_info *info = nci_get_drvdata(ndev);
+        u8 gate = ndev->hci_dev->pipes[pipe].gate;
+
+        pr_debug("cmd: %x\n", cmd);
+
+        switch (cmd) {
+        case NCI_HCI_ANY_OPEN_PIPE:
+                if (gate != ST21NFCB_APDU_READER_GATE &&
+                    ndev->hci_dev->pipes[pipe].host != ST21NFCB_UICC_HOST_ID)
+                        ndev->hci_dev->count_pipes++;
+
+                if (ndev->hci_dev->count_pipes ==
+                    ndev->hci_dev->expected_pipes) {
+                        del_timer_sync(&info->se_info.se_active_timer);
+                        info->se_info.se_active = false;
+                        ndev->hci_dev->count_pipes = 0;
+                        complete(&info->se_info.req_completion);
+                }
+        break;
+        }
+}
+EXPORT_SYMBOL_GPL(st21nfcb_hci_cmd_received);
+
+/*
+ * Remarks: On some early st21nfcb firmware, nci_nfcee_mode_set(0)
+ * is rejected
+ */
+static int st21nfcb_nci_control_se(struct nci_dev *ndev, u8 se_idx,
+                                   u8 state)
+{
+        struct st21nfcb_nci_info *info = nci_get_drvdata(ndev);
+        int r;
+        struct sk_buff *sk_host_list;
+        u8 host_id;
+
+        switch (se_idx) {
+        case ST21NFCB_UICC_HOST_ID:
+                ndev->hci_dev->count_pipes = 0;
+                ndev->hci_dev->expected_pipes = ST21NFCB_SE_COUNT_PIPE_UICC;
+                break;
+        case ST21NFCB_ESE_HOST_ID:
+                ndev->hci_dev->count_pipes = 0;
+                ndev->hci_dev->expected_pipes = ST21NFCB_SE_COUNT_PIPE_EMBEDDED;
+                break;
+        default:
+                return -EINVAL;
+        }
+
+        /*
+         * Wait for an EVT_HOT_PLUG in order to
+         * retrieve a relevant host list.
+         */
+        reinit_completion(&info->se_info.req_completion);
+        r = nci_nfcee_mode_set(ndev, se_idx, NCI_NFCEE_ENABLE);
+        if (r != NCI_STATUS_OK)
+                return r;
+
+        mod_timer(&info->se_info.se_active_timer, jiffies +
+                msecs_to_jiffies(ST21NFCB_SE_TO_HOT_PLUG));
+        info->se_info.se_active = true;
+
+        /* Ignore return value and check in any case the host_list */
+        wait_for_completion_interruptible(&info->se_info.req_completion);
+
+        /* There might be some "collision" after receiving a HOT_PLUG event
+         * This may cause the CLF to not answer to the next hci command.
+         * There is no possible synchronization to prevent this.
+         * Adding a small delay is the only way to solve the issue.
+         */
+        usleep_range(3000, 5000);
+
+        r = nci_hci_get_param(ndev, NCI_HCI_ADMIN_GATE,
+                        NCI_HCI_ADMIN_PARAM_HOST_LIST, &sk_host_list);
+        if (r != NCI_HCI_ANY_OK)
+                return r;
+
+        host_id = sk_host_list->data[sk_host_list->len - 1];
+        kfree_skb(sk_host_list);
+        if (state == ST21NFCB_SE_MODE_ON && host_id == se_idx)
+                return se_idx;
+        else if (state == ST21NFCB_SE_MODE_OFF && host_id != se_idx)
+                return se_idx;
+
+        return -1;
+}
+
+int st21nfcb_nci_disable_se(struct nci_dev *ndev, u32 se_idx)
+{
+        int r;
+
+        pr_debug("st21nfcb_nci_disable_se\n");
+
+        if (se_idx == NFC_SE_EMBEDDED) {
+                r = nci_hci_send_event(ndev, ST21NFCB_APDU_READER_GATE,
+                                ST21NFCB_EVT_SE_END_OF_APDU_TRANSFER, NULL, 0);
+                if (r < 0)
+                        return r;
+        }
+
+        return 0;
+}
+EXPORT_SYMBOL_GPL(st21nfcb_nci_disable_se);
+
+int st21nfcb_nci_enable_se(struct nci_dev *ndev, u32 se_idx)
+{
+        int r;
+
+        pr_debug("st21nfcb_nci_enable_se\n");
+
+        if (se_idx == ST21NFCB_HCI_HOST_ID_ESE) {
+                r = nci_hci_send_event(ndev, ST21NFCB_APDU_READER_GATE,
+                                ST21NFCB_EVT_SE_SOFT_RESET, NULL, 0);
+                if (r < 0)
+                        return r;
+        }
+
+        return 0;
+}
+EXPORT_SYMBOL_GPL(st21nfcb_nci_enable_se);
+
+static int st21nfcb_hci_network_init(struct nci_dev *ndev)
+{
+        struct core_conn_create_dest_spec_params dest_params;
+        struct nci_conn_info    *conn_info;
+        int r, dev_num;
+
+        r = nci_nfcee_discover(ndev, NCI_NFCEE_DISCOVERY_ACTION_ENABLE);
+        if (r != NCI_STATUS_OK)
+                goto exit;
+
+        dest_params.type = NCI_DESTINATION_SPECIFIC_PARAM_NFCEE_TYPE;
+        dest_params.length = sizeof(struct dest_spec_params);
+        dest_params.value.id = ndev->hci_dev->conn_info->id;
+        dest_params.value.protocol = NCI_NFCEE_INTERFACE_HCI_ACCESS;
+        r = nci_core_conn_create(ndev, &dest_params);
+        if (r != NCI_STATUS_OK)
+                goto exit;
+
+        conn_info = ndev->hci_dev->conn_info;
+        if (!conn_info)
+                goto exit;
+
+        memcpy(ndev->hci_dev->init_data.gates, st21nfcb_gates,
+               sizeof(st21nfcb_gates));
+
+        /*
+         * Session id must include the driver name + i2c bus addr
+         * persistent info to discriminate 2 identical chips
+         */
+        dev_num = find_first_zero_bit(dev_mask, ST21NFCB_NUM_DEVICES);
+        if (dev_num >= ST21NFCB_NUM_DEVICES)
+                return -ENODEV;
+
+        scnprintf(ndev->hci_dev->init_data.session_id,
+                  sizeof(ndev->hci_dev->init_data.session_id),
+                  "%s%2x", "ST21BH", dev_num);
+
+        r = nci_hci_dev_session_init(ndev);
+        if (r != NCI_HCI_ANY_OK)
+                goto exit;
+
+        r = nci_nfcee_mode_set(ndev, ndev->hci_dev->conn_info->id,
+                               NCI_NFCEE_ENABLE);
+        if (r != NCI_STATUS_OK)
+                goto exit;
+
+        return 0;
+
+exit:
+        return r;
+}
+
+int st21nfcb_nci_discover_se(struct nci_dev *ndev)
+{
+        u8 param[2];
+        int r;
+        int se_count = 0;
+
+        pr_debug("st21nfcb_nci_discover_se\n");
+
+        r = st21nfcb_hci_network_init(ndev);
+        if (r != 0)
+                return r;
+
+        param[0] = ST21NFCB_UICC_HOST_ID;
+        param[1] = ST21NFCB_HCI_HOST_ID_ESE;
+        r = nci_hci_set_param(ndev, NCI_HCI_ADMIN_GATE,
+                                NCI_HCI_ADMIN_PARAM_WHITELIST,
+                                param, sizeof(param));
+        if (r != NCI_HCI_ANY_OK)
+                return r;
+
+        r = st21nfcb_nci_control_se(ndev, ST21NFCB_UICC_HOST_ID,
+                                ST21NFCB_SE_MODE_ON);
+        if (r == ST21NFCB_UICC_HOST_ID) {
+                nfc_add_se(ndev->nfc_dev, ST21NFCB_UICC_HOST_ID, NFC_SE_UICC);
+                se_count++;
+        }
+
+        /* Try to enable eSE in order to check availability */
+        r = st21nfcb_nci_control_se(ndev, ST21NFCB_HCI_HOST_ID_ESE,
+                                ST21NFCB_SE_MODE_ON);
+        if (r == ST21NFCB_HCI_HOST_ID_ESE) {
+                nfc_add_se(ndev->nfc_dev, ST21NFCB_HCI_HOST_ID_ESE,
+                           NFC_SE_EMBEDDED);
+                se_count++;
+                st21nfcb_se_get_atr(ndev);
+        }
+
+        return !se_count;
+}
+EXPORT_SYMBOL_GPL(st21nfcb_nci_discover_se);
+
+int st21nfcb_nci_se_io(struct nci_dev *ndev, u32 se_idx,
+                       u8 *apdu, size_t apdu_length,
+                       se_io_cb_t cb, void *cb_context)
+{
+        struct st21nfcb_nci_info *info = nci_get_drvdata(ndev);
+
+        pr_debug("\n");
+
+        switch (se_idx) {
+        case ST21NFCB_HCI_HOST_ID_ESE:
+                info->se_info.cb = cb;
+                info->se_info.cb_context = cb_context;
+                mod_timer(&info->se_info.bwi_timer, jiffies +
+                          msecs_to_jiffies(info->se_info.wt_timeout));
+                info->se_info.bwi_active = true;
+                return nci_hci_send_event(ndev, ST21NFCB_APDU_READER_GATE,
+                                        ST21NFCB_EVT_TRANSMIT_DATA, apdu,
+                                        apdu_length);
+        default:
+                return -ENODEV;
+        }
+}
+EXPORT_SYMBOL(st21nfcb_nci_se_io);
+
+static void st21nfcb_se_wt_timeout(unsigned long data)
+{
+        /*
+         * No answer from the secure element
+         * within the defined timeout.
+         * Let's send a reset request as recovery procedure.
+         * According to the situation, we first try to send a software reset
+         * to the secure element. If the next command is still not
+         * answering in time, we send to the CLF a secure element hardware
+         * reset request.
+         */
+        /* hardware reset managed through VCC_UICC_OUT power supply */
+        u8 param = 0x01;
+        struct st21nfcb_nci_info *info = (struct st21nfcb_nci_info *) data;
+
+        pr_debug("\n");
+
+        info->se_info.bwi_active = false;
+
+        if (!info->se_info.xch_error) {
+                info->se_info.xch_error = true;
+                nci_hci_send_event(info->ndlc->ndev, ST21NFCB_APDU_READER_GATE,
+                                ST21NFCB_EVT_SE_SOFT_RESET, NULL, 0);
+        } else {
+                info->se_info.xch_error = false;
+                nci_hci_send_event(info->ndlc->ndev, ST21NFCB_DEVICE_MGNT_GATE,
+                                ST21NFCB_EVT_SE_HARD_RESET, &param, 1);
+        }
+        info->se_info.cb(info->se_info.cb_context, NULL, 0, -ETIME);
+}
+
+static void st21nfcb_se_activation_timeout(unsigned long data)
+{
+        struct st21nfcb_nci_info *info = (struct st21nfcb_nci_info *) data;
+
+        pr_debug("\n");
+
+        info->se_info.se_active = false;
+
+        complete(&info->se_info.req_completion);
+}
+
+int st21nfcb_se_init(struct nci_dev *ndev)
+{
+        struct st21nfcb_nci_info *info = nci_get_drvdata(ndev);
+
+        init_completion(&info->se_info.req_completion);
+        /* initialize timers */
+        init_timer(&info->se_info.bwi_timer);
+        info->se_info.bwi_timer.data = (unsigned long)info;
+        info->se_info.bwi_timer.function = st21nfcb_se_wt_timeout;
+        info->se_info.bwi_active = false;
+
+        init_timer(&info->se_info.se_active_timer);
+        info->se_info.se_active_timer.data = (unsigned long)info;
+        info->se_info.se_active_timer.function =
+                        st21nfcb_se_activation_timeout;
+        info->se_info.se_active = false;
+
+        info->se_info.xch_error = false;
+
+        info->se_info.wt_timeout =
+                ST21NFCB_BWI_TO_TIMEOUT(ST21NFCB_ATR_DEFAULT_BWI);
+
+        return 0;
+}
+EXPORT_SYMBOL(st21nfcb_se_init);
+
+void st21nfcb_se_deinit(struct nci_dev *ndev)
+{
+        struct st21nfcb_nci_info *info = nci_get_drvdata(ndev);
+
+        if (info->se_info.bwi_active)
+                del_timer_sync(&info->se_info.bwi_timer);
+        if (info->se_info.se_active)
+                del_timer_sync(&info->se_info.se_active_timer);
+
+        info->se_info.se_active = false;
+        info->se_info.bwi_active = false;
+}
+EXPORT_SYMBOL(st21nfcb_se_deinit);
+
diff --git a/drivers/nfc/st21nfcb/st21nfcb_se.h b/drivers/nfc/st21nfcb/st21nfcb_se.h
new file mode 100644
index 000000000000..52a323872bea
--- /dev/null
+++ b/drivers/nfc/st21nfcb/st21nfcb_se.h
@@ -0,0 +1,61 @@
+/*
+ * NCI based Driver for STMicroelectronics NFC Chip
+ *
+ * Copyright (C) 2014  STMicroelectronics SAS. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef __LOCAL_ST21NFCB_SE_H_
+#define __LOCAL_ST21NFCB_SE_H_
+
+/*
+ * ref ISO7816-3 chap 8.1. the initial character TS is followed by a
+ * sequence of at most 32 characters.
+ */
+#define ST21NFCB_ESE_MAX_LENGTH         33
+#define ST21NFCB_HCI_HOST_ID_ESE        0xc0
+
+struct st21nfcb_se_info {
+        u8 atr[ST21NFCB_ESE_MAX_LENGTH];
+        struct completion req_completion;
+
+        struct timer_list bwi_timer;
+        int wt_timeout; /* in msecs */
+        bool bwi_active;
+
+        struct timer_list se_active_timer;
+        bool se_active;
+
+        bool xch_error;
+
+        se_io_cb_t cb;
+        void *cb_context;
+};
+
+int st21nfcb_se_init(struct nci_dev *ndev);
+void st21nfcb_se_deinit(struct nci_dev *ndev);
+
+int st21nfcb_nci_discover_se(struct nci_dev *ndev);
+int st21nfcb_nci_enable_se(struct nci_dev *ndev, u32 se_idx);
+int st21nfcb_nci_disable_se(struct nci_dev *ndev, u32 se_idx);
+int st21nfcb_nci_se_io(struct nci_dev *ndev, u32 se_idx,
+                                        u8 *apdu, size_t apdu_length,
+                                        se_io_cb_t cb, void *cb_context);
+int st21nfcb_hci_load_session(struct nci_dev *ndev);
+void st21nfcb_hci_event_received(struct nci_dev *ndev, u8 pipe,
+                                 u8 event, struct sk_buff *skb);
+void st21nfcb_hci_cmd_received(struct nci_dev *ndev, u8 pipe, u8 cmd,
+                               struct sk_buff *skb);
+
+
+#endif /* __LOCAL_ST21NFCB_NCI_H_ */