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7d0911c02f
linux/net/nfc/digital_technology.c
Thierry Escande 7d0911c02f NFC Digital: Add initiator NFC-DEP support 
This adds support for NFC-DEP protocol in initiator mode for NFC-A and
NFC-F technologies.

When a target is detected, the process flow is as follow:

For NFC-A technology:
1 - The digital stack receives a SEL_RES as the reply of the SEL_REQ
    command.
2   - If b7 of SEL_RES is set, the peer device is configure for NFC-DEP
      protocol. NFC core is notified through nfc_targets_found().
      Execution continues at step 4.
3   - Otherwise, it's a tag and the NFC core is notified. Detection
      ends.
4 - The digital stacks sends an ATR_REQ command containing a randomly
    generated NFCID3 and the general bytes obtained from the LLCP layer
    of NFC core.

For NFC-F technology:
1 - The digital stack receives a SENSF_RES as the reply of the
    SENSF_REQ command.
2   - If B1 and B2 of NFCID2 are 0x01 and 0xFE respectively, the peer
      device is configured for NFC-DEP protocol. NFC core is notified
      through nfc_targets_found(). Execution continues at step 4.
3   - Otherwise it's a type 3 tag. NFC core is notified. Detection
      ends.
4 - The digital stacks sends an ATR_REQ command containing the NFC-F
    NFCID2 as NFCID3 and the general bytes obtained from the LLCP layer
    of NFC core.

For both technologies:
5 - The digital stacks receives the ATR_RES response containing the
    NFCID3 and the general bytes of the peer device.
6 - The digital stack notifies NFC core that the DEP link is up through
    nfc_dep_link_up().
7 - The NFC core performs data exchange through tm_transceive().
8 - The digital stack sends a DEP_REQ command containing an I PDU with
    the data from NFC core.
9 - The digital stack receives a DEP_RES command
10  - If the DEP_RES response contains a supervisor PDU with timeout
      extension request (RTOX) the digital stack sends a DEP_REQ
      command containing a supervisor PDU acknowledging the RTOX
      request. The execution continues at step 9.
11  - If the DEP_RES response contains an I PDU, the response data is
      passed back to NFC core through the response callback. The
      execution continues at step 8.

Signed-off-by: Thierry Escande <thierry.escande@linux.intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2013-09-25 02:02:27 +02:00

478 lines
9.9 KiB
C
Raw Blame History

/*
* NFC Digital Protocol stack
* Copyright (c) 2013, Intel Corporation.
*
* 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 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.
*
*/
#include "digital.h"
#define DIGITAL_CMD_SENS_REQ 0x26
#define DIGITAL_CMD_ALL_REQ 0x52
#define DIGITAL_CMD_SEL_REQ_CL1 0x93
#define DIGITAL_CMD_SEL_REQ_CL2 0x95
#define DIGITAL_CMD_SEL_REQ_CL3 0x97
#define DIGITAL_SDD_REQ_SEL_PAR 0x20
#define DIGITAL_SDD_RES_CT 0x88
#define DIGITAL_SDD_RES_LEN 5
#define DIGITAL_SEL_RES_NFCID1_COMPLETE(sel_res) (!((sel_res) & 0x04))
#define DIGITAL_SEL_RES_IS_T2T(sel_res) (!((sel_res) & 0x60))
#define DIGITAL_SEL_RES_IS_NFC_DEP(sel_res) ((sel_res) & 0x40)
#define DIGITAL_SENS_RES_IS_T1T(sens_res) (((sens_res) & 0x000C) == 0x000C)
#define DIGITAL_SENS_RES_IS_VALID(sens_res) \
((!((sens_res) & 0x1F00) && (((sens_res) & 0x000C) == 0x000C)) || \
(((sens_res) & 0x1F00) && ((sens_res) & 0x000C) != 0x000C))
#define DIGITAL_MIFARE_READ_RES_LEN 16
#define DIGITAL_MIFARE_ACK_RES 0x0A
#define DIGITAL_CMD_SENSF_REQ 0x00
#define DIGITAL_CMD_SENSF_RES 0x01
#define DIGITAL_SENSF_RES_MIN_LENGTH 17
#define DIGITAL_SENSF_RES_RD_AP_B1 0x00
#define DIGITAL_SENSF_RES_RD_AP_B2 0x8F
#define DIGITAL_SENSF_REQ_RC_NONE 0
#define DIGITAL_SENSF_REQ_RC_SC 1
#define DIGITAL_SENSF_REQ_RC_AP 2
struct digital_sdd_res {
u8 nfcid1[4];
u8 bcc;
} __packed;
struct digital_sel_req {
u8 sel_cmd;
u8 b2;
u8 nfcid1[4];
u8 bcc;
} __packed;
struct digital_sensf_req {
u8 cmd;
u8 sc1;
u8 sc2;
u8 rc;
u8 tsn;
} __packed;
struct digital_sensf_res {
u8 cmd;
u8 nfcid2[8];
u8 pad0[2];
u8 pad1[3];
u8 mrti_check;
u8 mrti_update;
u8 pad2;
u8 rd[2];
} __packed;
static int digital_in_send_sdd_req(struct nfc_digital_dev *ddev,
struct nfc_target *target);
static void digital_in_recv_sel_res(struct nfc_digital_dev *ddev, void *arg,
struct sk_buff *resp)
{
struct nfc_target *target = arg;
int rc;
u8 sel_res;
u8 nfc_proto;
if (IS_ERR(resp)) {
rc = PTR_ERR(resp);
resp = NULL;
goto exit;
}
if (!DIGITAL_DRV_CAPS_IN_CRC(ddev)) {
rc = digital_skb_check_crc_a(resp);
if (rc) {
PROTOCOL_ERR("4.4.1.3");
goto exit;
}
}
if (!resp->len) {
rc = -EIO;
goto exit;
}
sel_res = resp->data[0];
if (!DIGITAL_SEL_RES_NFCID1_COMPLETE(sel_res)) {
rc = digital_in_send_sdd_req(ddev, target);
if (rc)
goto exit;
goto exit_free_skb;
}
if (DIGITAL_SEL_RES_IS_T2T(sel_res)) {
nfc_proto = NFC_PROTO_MIFARE;
} else if (DIGITAL_SEL_RES_IS_NFC_DEP(sel_res)) {
nfc_proto = NFC_PROTO_NFC_DEP;
} else {
rc = -EOPNOTSUPP;
goto exit;
}
target->sel_res = sel_res;
rc = digital_target_found(ddev, target, nfc_proto);
exit:
kfree(target);
exit_free_skb:
dev_kfree_skb(resp);
if (rc)
digital_poll_next_tech(ddev);
}
static int digital_in_send_sel_req(struct nfc_digital_dev *ddev,
struct nfc_target *target,
struct digital_sdd_res *sdd_res)
{
struct sk_buff *skb;
struct digital_sel_req *sel_req;
u8 sel_cmd;
int rc;
skb = digital_skb_alloc(ddev, sizeof(struct digital_sel_req));
if (!skb)
return -ENOMEM;
skb_put(skb, sizeof(struct digital_sel_req));
sel_req = (struct digital_sel_req *)skb->data;
if (target->nfcid1_len <= 4)
sel_cmd = DIGITAL_CMD_SEL_REQ_CL1;
else if (target->nfcid1_len < 10)
sel_cmd = DIGITAL_CMD_SEL_REQ_CL2;
else
sel_cmd = DIGITAL_CMD_SEL_REQ_CL3;
sel_req->sel_cmd = sel_cmd;
sel_req->b2 = 0x70;
memcpy(sel_req->nfcid1, sdd_res->nfcid1, 4);
sel_req->bcc = sdd_res->bcc;
if (DIGITAL_DRV_CAPS_IN_CRC(ddev)) {
rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A);
if (rc)
goto exit;
} else {
digital_skb_add_crc_a(skb);
}
rc = digital_in_send_cmd(ddev, skb, 30, digital_in_recv_sel_res,
target);
exit:
if (rc)
kfree_skb(skb);
return rc;
}
static void digital_in_recv_sdd_res(struct nfc_digital_dev *ddev, void *arg,
struct sk_buff *resp)
{
struct nfc_target *target = arg;
struct digital_sdd_res *sdd_res;
int rc;
u8 offset, size;
u8 i, bcc;
if (IS_ERR(resp)) {
rc = PTR_ERR(resp);
resp = NULL;
goto exit;
}
if (resp->len < DIGITAL_SDD_RES_LEN) {
PROTOCOL_ERR("4.7.2.8");
rc = -EINVAL;
goto exit;
}
sdd_res = (struct digital_sdd_res *)resp->data;
for (i = 0, bcc = 0; i < 4; i++)
bcc ^= sdd_res->nfcid1[i];
if (bcc != sdd_res->bcc) {
PROTOCOL_ERR("4.7.2.6");
rc = -EINVAL;
goto exit;
}
if (sdd_res->nfcid1[0] == DIGITAL_SDD_RES_CT) {
offset = 1;
size = 3;
} else {
offset = 0;
size = 4;
}
memcpy(target->nfcid1 + target->nfcid1_len, sdd_res->nfcid1 + offset,
size);
target->nfcid1_len += size;
rc = digital_in_send_sel_req(ddev, target, sdd_res);
exit:
dev_kfree_skb(resp);
if (rc) {
kfree(target);
digital_poll_next_tech(ddev);
}
}
static int digital_in_send_sdd_req(struct nfc_digital_dev *ddev,
struct nfc_target *target)
{
int rc;
struct sk_buff *skb;
u8 sel_cmd;
rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
NFC_DIGITAL_FRAMING_NFCA_STANDARD);
if (rc)
return rc;
skb = digital_skb_alloc(ddev, 2);
if (!skb) {
PR_ERR("alloc_skb failed");
return -ENOMEM;
}
if (target->nfcid1_len == 0)
sel_cmd = DIGITAL_CMD_SEL_REQ_CL1;
else if (target->nfcid1_len == 3)
sel_cmd = DIGITAL_CMD_SEL_REQ_CL2;
else
sel_cmd = DIGITAL_CMD_SEL_REQ_CL3;
*skb_put(skb, sizeof(u8)) = sel_cmd;
*skb_put(skb, sizeof(u8)) = DIGITAL_SDD_REQ_SEL_PAR;
return digital_in_send_cmd(ddev, skb, 30, digital_in_recv_sdd_res,
target);
}
static void digital_in_recv_sens_res(struct nfc_digital_dev *ddev, void *arg,
struct sk_buff *resp)
{
struct nfc_target *target = NULL;
u16 sens_res;
int rc;
if (IS_ERR(resp)) {
rc = PTR_ERR(resp);
resp = NULL;
goto exit;
}
if (resp->len < sizeof(u16)) {
rc = -EIO;
goto exit;
}
target = kzalloc(sizeof(struct nfc_target), GFP_KERNEL);
if (!target) {
rc = -ENOMEM;
goto exit;
}
memcpy(&target->sens_res, resp->data, sizeof(u16));
sens_res = be16_to_cpu(target->sens_res);
if (!DIGITAL_SENS_RES_IS_VALID(sens_res)) {
PROTOCOL_ERR("4.6.3.3");
rc = -EINVAL;
goto exit;
}
if (DIGITAL_SENS_RES_IS_T1T(sens_res))
rc = digital_target_found(ddev, target, NFC_PROTO_JEWEL);
else
rc = digital_in_send_sdd_req(ddev, target);
exit:
dev_kfree_skb(resp);
if (rc) {
kfree(target);
digital_poll_next_tech(ddev);
}
}
int digital_in_send_sens_req(struct nfc_digital_dev *ddev, u8 rf_tech)
{
struct sk_buff *skb;
int rc;
rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH,
NFC_DIGITAL_RF_TECH_106A);
if (rc)
return rc;
rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
NFC_DIGITAL_FRAMING_NFCA_SHORT);
if (rc)
return rc;
skb = digital_skb_alloc(ddev, 1);
if (!skb)
return -ENOMEM;
*skb_put(skb, sizeof(u8)) = DIGITAL_CMD_SENS_REQ;
rc = digital_in_send_cmd(ddev, skb, 30, digital_in_recv_sens_res, NULL);
if (rc)
kfree_skb(skb);
return rc;
}
int digital_in_recv_mifare_res(struct sk_buff *resp)
{
/* Successful READ command response is 16 data bytes + 2 CRC bytes long.
* Since the driver can't differentiate a ACK/NACK response from a valid
* READ response, the CRC calculation must be handled at digital level
* even if the driver supports it for this technology.
*/
if (resp->len == DIGITAL_MIFARE_READ_RES_LEN + DIGITAL_CRC_LEN) {
if (digital_skb_check_crc_a(resp)) {
PROTOCOL_ERR("9.4.1.2");
return -EIO;
}
return 0;
}
/* ACK response (i.e. successful WRITE). */
if (resp->len == 1 && resp->data[0] == DIGITAL_MIFARE_ACK_RES) {
resp->data[0] = 0;
return 0;
}
/* NACK and any other responses are treated as error. */
return -EIO;
}
static void digital_in_recv_sensf_res(struct nfc_digital_dev *ddev, void *arg,
struct sk_buff *resp)
{
int rc;
u8 proto;
struct nfc_target target;
struct digital_sensf_res *sensf_res;
if (IS_ERR(resp)) {
rc = PTR_ERR(resp);
resp = NULL;
goto exit;
}
if (resp->len < DIGITAL_SENSF_RES_MIN_LENGTH) {
rc = -EIO;
goto exit;
}
if (!DIGITAL_DRV_CAPS_IN_CRC(ddev)) {
rc = digital_skb_check_crc_f(resp);
if (rc) {
PROTOCOL_ERR("6.4.1.8");
goto exit;
}
}
skb_pull(resp, 1);
memset(&target, 0, sizeof(struct nfc_target));
sensf_res = (struct digital_sensf_res *)resp->data;
memcpy(target.sensf_res, sensf_res, resp->len);
target.sensf_res_len = resp->len;
memcpy(target.nfcid2, sensf_res->nfcid2, NFC_NFCID2_MAXSIZE);
target.nfcid2_len = NFC_NFCID2_MAXSIZE;
if (target.nfcid2[0] == DIGITAL_SENSF_NFCID2_NFC_DEP_B1 &&
target.nfcid2[1] == DIGITAL_SENSF_NFCID2_NFC_DEP_B2)
proto = NFC_PROTO_NFC_DEP;
else
proto = NFC_PROTO_FELICA;
rc = digital_target_found(ddev, &target, proto);
exit:
dev_kfree_skb(resp);
if (rc)
digital_poll_next_tech(ddev);
}
int digital_in_send_sensf_req(struct nfc_digital_dev *ddev, u8 rf_tech)
{
struct digital_sensf_req *sensf_req;
struct sk_buff *skb;
int rc;
u8 size;
rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH, rf_tech);
if (rc)
return rc;
rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
NFC_DIGITAL_FRAMING_NFCF);
if (rc)
return rc;
size = sizeof(struct digital_sensf_req);
skb = digital_skb_alloc(ddev, size);
if (!skb)
return -ENOMEM;
skb_put(skb, size);
sensf_req = (struct digital_sensf_req *)skb->data;
sensf_req->cmd = DIGITAL_CMD_SENSF_REQ;
sensf_req->sc1 = 0xFF;
sensf_req->sc2 = 0xFF;
sensf_req->rc = 0;
sensf_req->tsn = 0;
*skb_push(skb, 1) = size + 1;
if (!DIGITAL_DRV_CAPS_IN_CRC(ddev))
digital_skb_add_crc_f(skb);
rc = digital_in_send_cmd(ddev, skb, 30, digital_in_recv_sensf_res,
NULL);
if (rc)
kfree_skb(skb);
return rc;
}
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