From 76cb841cb886eef6b3bee341a2266c76578724ad Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Mon, 6 May 2024 03:02:30 +0200 Subject: Adding upstream version 4.19.249. Signed-off-by: Daniel Baumann --- net/nfc/digital_dep.c | 1645 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1645 insertions(+) create mode 100644 net/nfc/digital_dep.c (limited to 'net/nfc/digital_dep.c') diff --git a/net/nfc/digital_dep.c b/net/nfc/digital_dep.c new file mode 100644 index 000000000..1eed0cf59 --- /dev/null +++ b/net/nfc/digital_dep.c @@ -0,0 +1,1645 @@ +/* + * 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. + * + */ + +#define pr_fmt(fmt) "digital: %s: " fmt, __func__ + +#include "digital.h" + +#define DIGITAL_NFC_DEP_N_RETRY_NACK 2 +#define DIGITAL_NFC_DEP_N_RETRY_ATN 2 + +#define DIGITAL_NFC_DEP_FRAME_DIR_OUT 0xD4 +#define DIGITAL_NFC_DEP_FRAME_DIR_IN 0xD5 + +#define DIGITAL_NFC_DEP_NFCA_SOD_SB 0xF0 + +#define DIGITAL_CMD_ATR_REQ 0x00 +#define DIGITAL_CMD_ATR_RES 0x01 +#define DIGITAL_CMD_PSL_REQ 0x04 +#define DIGITAL_CMD_PSL_RES 0x05 +#define DIGITAL_CMD_DEP_REQ 0x06 +#define DIGITAL_CMD_DEP_RES 0x07 + +#define DIGITAL_ATR_REQ_MIN_SIZE 16 +#define DIGITAL_ATR_REQ_MAX_SIZE 64 + +#define DIGITAL_ATR_RES_TO_WT(s) ((s) & 0xF) + +#define DIGITAL_DID_MAX 14 + +#define DIGITAL_PAYLOAD_SIZE_MAX 254 +#define DIGITAL_PAYLOAD_BITS_TO_PP(s) (((s) & 0x3) << 4) +#define DIGITAL_PAYLOAD_PP_TO_BITS(s) (((s) >> 4) & 0x3) +#define DIGITAL_PAYLOAD_BITS_TO_FSL(s) ((s) & 0x3) +#define DIGITAL_PAYLOAD_FSL_TO_BITS(s) ((s) & 0x3) + +#define DIGITAL_GB_BIT 0x02 + +#define DIGITAL_NFC_DEP_REQ_RES_HEADROOM 2 /* SoD: [SB (NFC-A)] + LEN */ +#define DIGITAL_NFC_DEP_REQ_RES_TAILROOM 2 /* EoD: 2-byte CRC */ + +#define DIGITAL_NFC_DEP_PFB_TYPE(pfb) ((pfb) & 0xE0) + +#define DIGITAL_NFC_DEP_PFB_TIMEOUT_BIT 0x10 +#define DIGITAL_NFC_DEP_PFB_MI_BIT 0x10 +#define DIGITAL_NFC_DEP_PFB_NACK_BIT 0x10 +#define DIGITAL_NFC_DEP_PFB_DID_BIT 0x04 + +#define DIGITAL_NFC_DEP_PFB_IS_TIMEOUT(pfb) \ + ((pfb) & DIGITAL_NFC_DEP_PFB_TIMEOUT_BIT) +#define DIGITAL_NFC_DEP_MI_BIT_SET(pfb) ((pfb) & DIGITAL_NFC_DEP_PFB_MI_BIT) +#define DIGITAL_NFC_DEP_NACK_BIT_SET(pfb) ((pfb) & DIGITAL_NFC_DEP_PFB_NACK_BIT) +#define DIGITAL_NFC_DEP_NAD_BIT_SET(pfb) ((pfb) & 0x08) +#define DIGITAL_NFC_DEP_DID_BIT_SET(pfb) ((pfb) & DIGITAL_NFC_DEP_PFB_DID_BIT) +#define DIGITAL_NFC_DEP_PFB_PNI(pfb) ((pfb) & 0x03) + +#define DIGITAL_NFC_DEP_RTOX_VALUE(data) ((data) & 0x3F) +#define DIGITAL_NFC_DEP_RTOX_MAX 59 + +#define DIGITAL_NFC_DEP_PFB_I_PDU 0x00 +#define DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU 0x40 +#define DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU 0x80 + +struct digital_atr_req { + u8 dir; + u8 cmd; + u8 nfcid3[10]; + u8 did; + u8 bs; + u8 br; + u8 pp; + u8 gb[0]; +} __packed; + +struct digital_atr_res { + u8 dir; + u8 cmd; + u8 nfcid3[10]; + u8 did; + u8 bs; + u8 br; + u8 to; + u8 pp; + u8 gb[0]; +} __packed; + +struct digital_psl_req { + u8 dir; + u8 cmd; + u8 did; + u8 brs; + u8 fsl; +} __packed; + +struct digital_psl_res { + u8 dir; + u8 cmd; + u8 did; +} __packed; + +struct digital_dep_req_res { + u8 dir; + u8 cmd; + u8 pfb; +} __packed; + +static void digital_in_recv_dep_res(struct nfc_digital_dev *ddev, void *arg, + struct sk_buff *resp); +static void digital_tg_recv_dep_req(struct nfc_digital_dev *ddev, void *arg, + struct sk_buff *resp); + +static const u8 digital_payload_bits_map[4] = { + [0] = 64, + [1] = 128, + [2] = 192, + [3] = 254 +}; + +/* Response Waiting Time for ATR_RES PDU in ms + * + * RWT(ATR_RES) = RWT(nfcdep,activation) + dRWT(nfcdep) + dT(nfcdep,initiator) + * + * with: + * RWT(nfcdep,activation) = 4096 * 2^12 / f(c) s + * dRWT(nfcdep) = 16 / f(c) s + * dT(nfcdep,initiator) = 100 ms + * f(c) = 13560000 Hz + */ +#define DIGITAL_ATR_RES_RWT 1337 + +/* Response Waiting Time for other DEP PDUs in ms + * + * max_rwt = rwt + dRWT(nfcdep) + dT(nfcdep,initiator) + * + * with: + * rwt = (256 * 16 / f(c)) * 2^wt s + * dRWT(nfcdep) = 16 / f(c) s + * dT(nfcdep,initiator) = 100 ms + * f(c) = 13560000 Hz + * 0 <= wt <= 14 (given by the target by the TO field of ATR_RES response) + */ +#define DIGITAL_NFC_DEP_IN_MAX_WT 14 +#define DIGITAL_NFC_DEP_TG_MAX_WT 14 +static const u16 digital_rwt_map[DIGITAL_NFC_DEP_IN_MAX_WT + 1] = { + 100, 101, 101, 102, 105, + 110, 119, 139, 177, 255, + 409, 719, 1337, 2575, 5049, +}; + +static u8 digital_payload_bits_to_size(u8 payload_bits) +{ + if (payload_bits >= ARRAY_SIZE(digital_payload_bits_map)) + return 0; + + return digital_payload_bits_map[payload_bits]; +} + +static u8 digital_payload_size_to_bits(u8 payload_size) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(digital_payload_bits_map); i++) + if (digital_payload_bits_map[i] == payload_size) + return i; + + return 0xff; +} + +static void digital_skb_push_dep_sod(struct nfc_digital_dev *ddev, + struct sk_buff *skb) +{ + skb_push(skb, sizeof(u8)); + + skb->data[0] = skb->len; + + if (ddev->curr_rf_tech == NFC_DIGITAL_RF_TECH_106A) + *(u8 *)skb_push(skb, sizeof(u8)) = DIGITAL_NFC_DEP_NFCA_SOD_SB; +} + +static int digital_skb_pull_dep_sod(struct nfc_digital_dev *ddev, + struct sk_buff *skb) +{ + u8 size; + + if (skb->len < 2) + return -EIO; + + if (ddev->curr_rf_tech == NFC_DIGITAL_RF_TECH_106A) + skb_pull(skb, sizeof(u8)); + + size = skb->data[0]; + if (size != skb->len) + return -EIO; + + skb_pull(skb, sizeof(u8)); + + return 0; +} + +static struct sk_buff * +digital_send_dep_data_prep(struct nfc_digital_dev *ddev, struct sk_buff *skb, + struct digital_dep_req_res *dep_req_res, + struct digital_data_exch *data_exch) +{ + struct sk_buff *new_skb; + + if (skb->len > ddev->remote_payload_max) { + dep_req_res->pfb |= DIGITAL_NFC_DEP_PFB_MI_BIT; + + new_skb = digital_skb_alloc(ddev, ddev->remote_payload_max); + if (!new_skb) { + kfree_skb(ddev->chaining_skb); + ddev->chaining_skb = NULL; + + return ERR_PTR(-ENOMEM); + } + + skb_put_data(new_skb, skb->data, ddev->remote_payload_max); + skb_pull(skb, ddev->remote_payload_max); + + ddev->chaining_skb = skb; + ddev->data_exch = data_exch; + } else { + ddev->chaining_skb = NULL; + new_skb = skb; + } + + return new_skb; +} + +static struct sk_buff * +digital_recv_dep_data_gather(struct nfc_digital_dev *ddev, u8 pfb, + struct sk_buff *resp, + int (*send_ack)(struct nfc_digital_dev *ddev, + struct digital_data_exch + *data_exch), + struct digital_data_exch *data_exch) +{ + struct sk_buff *new_skb; + int rc; + + if (DIGITAL_NFC_DEP_MI_BIT_SET(pfb) && (!ddev->chaining_skb)) { + ddev->chaining_skb = + nfc_alloc_recv_skb(8 * ddev->local_payload_max, + GFP_KERNEL); + if (!ddev->chaining_skb) { + rc = -ENOMEM; + goto error; + } + } + + if (ddev->chaining_skb) { + if (resp->len > skb_tailroom(ddev->chaining_skb)) { + new_skb = skb_copy_expand(ddev->chaining_skb, + skb_headroom( + ddev->chaining_skb), + 8 * ddev->local_payload_max, + GFP_KERNEL); + if (!new_skb) { + rc = -ENOMEM; + goto error; + } + + kfree_skb(ddev->chaining_skb); + ddev->chaining_skb = new_skb; + } + + skb_put_data(ddev->chaining_skb, resp->data, resp->len); + + kfree_skb(resp); + resp = NULL; + + if (DIGITAL_NFC_DEP_MI_BIT_SET(pfb)) { + rc = send_ack(ddev, data_exch); + if (rc) + goto error; + + return NULL; + } + + resp = ddev->chaining_skb; + ddev->chaining_skb = NULL; + } + + return resp; + +error: + kfree_skb(resp); + + kfree_skb(ddev->chaining_skb); + ddev->chaining_skb = NULL; + + return ERR_PTR(rc); +} + +static void digital_in_recv_psl_res(struct nfc_digital_dev *ddev, void *arg, + struct sk_buff *resp) +{ + struct nfc_target *target = arg; + struct digital_psl_res *psl_res; + int rc; + + if (IS_ERR(resp)) { + rc = PTR_ERR(resp); + resp = NULL; + goto exit; + } + + rc = ddev->skb_check_crc(resp); + if (rc) { + PROTOCOL_ERR("14.4.1.6"); + goto exit; + } + + rc = digital_skb_pull_dep_sod(ddev, resp); + if (rc) { + PROTOCOL_ERR("14.4.1.2"); + goto exit; + } + + psl_res = (struct digital_psl_res *)resp->data; + + if ((resp->len != sizeof(*psl_res)) || + (psl_res->dir != DIGITAL_NFC_DEP_FRAME_DIR_IN) || + (psl_res->cmd != DIGITAL_CMD_PSL_RES)) { + rc = -EIO; + goto exit; + } + + rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH, + NFC_DIGITAL_RF_TECH_424F); + if (rc) + goto exit; + + rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING, + NFC_DIGITAL_FRAMING_NFCF_NFC_DEP); + if (rc) + goto exit; + + if (!DIGITAL_DRV_CAPS_IN_CRC(ddev) && + (ddev->curr_rf_tech == NFC_DIGITAL_RF_TECH_106A)) { + ddev->skb_add_crc = digital_skb_add_crc_f; + ddev->skb_check_crc = digital_skb_check_crc_f; + } + + ddev->curr_rf_tech = NFC_DIGITAL_RF_TECH_424F; + + nfc_dep_link_is_up(ddev->nfc_dev, target->idx, NFC_COMM_ACTIVE, + NFC_RF_INITIATOR); + + ddev->curr_nfc_dep_pni = 0; + +exit: + dev_kfree_skb(resp); + + if (rc) + ddev->curr_protocol = 0; +} + +static int digital_in_send_psl_req(struct nfc_digital_dev *ddev, + struct nfc_target *target) +{ + struct sk_buff *skb; + struct digital_psl_req *psl_req; + int rc; + u8 payload_size, payload_bits; + + skb = digital_skb_alloc(ddev, sizeof(*psl_req)); + if (!skb) + return -ENOMEM; + + skb_put(skb, sizeof(*psl_req)); + + psl_req = (struct digital_psl_req *)skb->data; + + psl_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT; + psl_req->cmd = DIGITAL_CMD_PSL_REQ; + psl_req->did = 0; + psl_req->brs = (0x2 << 3) | 0x2; /* 424F both directions */ + + payload_size = min(ddev->local_payload_max, ddev->remote_payload_max); + payload_bits = digital_payload_size_to_bits(payload_size); + psl_req->fsl = DIGITAL_PAYLOAD_BITS_TO_FSL(payload_bits); + + ddev->local_payload_max = payload_size; + ddev->remote_payload_max = payload_size; + + digital_skb_push_dep_sod(ddev, skb); + + ddev->skb_add_crc(skb); + + rc = digital_in_send_cmd(ddev, skb, ddev->dep_rwt, + digital_in_recv_psl_res, target); + if (rc) + kfree_skb(skb); + + return rc; +} + +static void digital_in_recv_atr_res(struct nfc_digital_dev *ddev, void *arg, + struct sk_buff *resp) +{ + struct nfc_target *target = arg; + struct digital_atr_res *atr_res; + u8 gb_len, payload_bits; + u8 wt; + int rc; + + if (IS_ERR(resp)) { + rc = PTR_ERR(resp); + resp = NULL; + goto exit; + } + + rc = ddev->skb_check_crc(resp); + if (rc) { + PROTOCOL_ERR("14.4.1.6"); + goto exit; + } + + rc = digital_skb_pull_dep_sod(ddev, resp); + if (rc) { + PROTOCOL_ERR("14.4.1.2"); + goto exit; + } + + if (resp->len < sizeof(struct digital_atr_res)) { + rc = -EIO; + goto exit; + } + + gb_len = resp->len - sizeof(struct digital_atr_res); + + atr_res = (struct digital_atr_res *)resp->data; + + wt = DIGITAL_ATR_RES_TO_WT(atr_res->to); + if (wt > DIGITAL_NFC_DEP_IN_MAX_WT) + wt = DIGITAL_NFC_DEP_IN_MAX_WT; + ddev->dep_rwt = digital_rwt_map[wt]; + + payload_bits = DIGITAL_PAYLOAD_PP_TO_BITS(atr_res->pp); + ddev->remote_payload_max = digital_payload_bits_to_size(payload_bits); + + if (!ddev->remote_payload_max) { + rc = -EINVAL; + goto exit; + } + + rc = nfc_set_remote_general_bytes(ddev->nfc_dev, atr_res->gb, gb_len); + if (rc) + goto exit; + + if ((ddev->protocols & NFC_PROTO_FELICA_MASK) && + (ddev->curr_rf_tech != NFC_DIGITAL_RF_TECH_424F)) { + rc = digital_in_send_psl_req(ddev, target); + if (!rc) + goto exit; + } + + rc = nfc_dep_link_is_up(ddev->nfc_dev, target->idx, NFC_COMM_ACTIVE, + NFC_RF_INITIATOR); + + ddev->curr_nfc_dep_pni = 0; + +exit: + dev_kfree_skb(resp); + + if (rc) + ddev->curr_protocol = 0; +} + +int digital_in_send_atr_req(struct nfc_digital_dev *ddev, + struct nfc_target *target, __u8 comm_mode, __u8 *gb, + size_t gb_len) +{ + struct sk_buff *skb; + struct digital_atr_req *atr_req; + uint size; + int rc; + u8 payload_bits; + + size = DIGITAL_ATR_REQ_MIN_SIZE + gb_len; + + if (size > DIGITAL_ATR_REQ_MAX_SIZE) { + PROTOCOL_ERR("14.6.1.1"); + return -EINVAL; + } + + skb = digital_skb_alloc(ddev, size); + if (!skb) + return -ENOMEM; + + skb_put(skb, sizeof(struct digital_atr_req)); + + atr_req = (struct digital_atr_req *)skb->data; + memset(atr_req, 0, sizeof(struct digital_atr_req)); + + atr_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT; + atr_req->cmd = DIGITAL_CMD_ATR_REQ; + if (target->nfcid2_len) + memcpy(atr_req->nfcid3, target->nfcid2, NFC_NFCID2_MAXSIZE); + else + get_random_bytes(atr_req->nfcid3, NFC_NFCID3_MAXSIZE); + + atr_req->did = 0; + atr_req->bs = 0; + atr_req->br = 0; + + ddev->local_payload_max = DIGITAL_PAYLOAD_SIZE_MAX; + payload_bits = digital_payload_size_to_bits(ddev->local_payload_max); + atr_req->pp = DIGITAL_PAYLOAD_BITS_TO_PP(payload_bits); + + if (gb_len) { + atr_req->pp |= DIGITAL_GB_BIT; + skb_put_data(skb, gb, gb_len); + } + + digital_skb_push_dep_sod(ddev, skb); + + ddev->skb_add_crc(skb); + + rc = digital_in_send_cmd(ddev, skb, DIGITAL_ATR_RES_RWT, + digital_in_recv_atr_res, target); + if (rc) + kfree_skb(skb); + + return rc; +} + +static int digital_in_send_ack(struct nfc_digital_dev *ddev, + struct digital_data_exch *data_exch) +{ + struct digital_dep_req_res *dep_req; + struct sk_buff *skb; + int rc; + + skb = digital_skb_alloc(ddev, 1); + if (!skb) + return -ENOMEM; + + skb_push(skb, sizeof(struct digital_dep_req_res)); + + dep_req = (struct digital_dep_req_res *)skb->data; + + dep_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT; + dep_req->cmd = DIGITAL_CMD_DEP_REQ; + dep_req->pfb = DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU | + ddev->curr_nfc_dep_pni; + + digital_skb_push_dep_sod(ddev, skb); + + ddev->skb_add_crc(skb); + + ddev->saved_skb = pskb_copy(skb, GFP_KERNEL); + + rc = digital_in_send_cmd(ddev, skb, ddev->dep_rwt, + digital_in_recv_dep_res, data_exch); + if (rc) { + kfree_skb(skb); + kfree_skb(ddev->saved_skb); + ddev->saved_skb = NULL; + } + + return rc; +} + +static int digital_in_send_nack(struct nfc_digital_dev *ddev, + struct digital_data_exch *data_exch) +{ + struct digital_dep_req_res *dep_req; + struct sk_buff *skb; + int rc; + + skb = digital_skb_alloc(ddev, 1); + if (!skb) + return -ENOMEM; + + skb_push(skb, sizeof(struct digital_dep_req_res)); + + dep_req = (struct digital_dep_req_res *)skb->data; + + dep_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT; + dep_req->cmd = DIGITAL_CMD_DEP_REQ; + dep_req->pfb = DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU | + DIGITAL_NFC_DEP_PFB_NACK_BIT | ddev->curr_nfc_dep_pni; + + digital_skb_push_dep_sod(ddev, skb); + + ddev->skb_add_crc(skb); + + rc = digital_in_send_cmd(ddev, skb, ddev->dep_rwt, + digital_in_recv_dep_res, data_exch); + if (rc) + kfree_skb(skb); + + return rc; +} + +static int digital_in_send_atn(struct nfc_digital_dev *ddev, + struct digital_data_exch *data_exch) +{ + struct digital_dep_req_res *dep_req; + struct sk_buff *skb; + int rc; + + skb = digital_skb_alloc(ddev, 1); + if (!skb) + return -ENOMEM; + + skb_push(skb, sizeof(struct digital_dep_req_res)); + + dep_req = (struct digital_dep_req_res *)skb->data; + + dep_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT; + dep_req->cmd = DIGITAL_CMD_DEP_REQ; + dep_req->pfb = DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU; + + digital_skb_push_dep_sod(ddev, skb); + + ddev->skb_add_crc(skb); + + rc = digital_in_send_cmd(ddev, skb, ddev->dep_rwt, + digital_in_recv_dep_res, data_exch); + if (rc) + kfree_skb(skb); + + return rc; +} + +static int digital_in_send_rtox(struct nfc_digital_dev *ddev, + struct digital_data_exch *data_exch, u8 rtox) +{ + struct digital_dep_req_res *dep_req; + struct sk_buff *skb; + int rc; + u16 rwt_int; + + rwt_int = ddev->dep_rwt * rtox; + if (rwt_int > digital_rwt_map[DIGITAL_NFC_DEP_IN_MAX_WT]) + rwt_int = digital_rwt_map[DIGITAL_NFC_DEP_IN_MAX_WT]; + + skb = digital_skb_alloc(ddev, 1); + if (!skb) + return -ENOMEM; + + skb_put_u8(skb, rtox); + + skb_push(skb, sizeof(struct digital_dep_req_res)); + + dep_req = (struct digital_dep_req_res *)skb->data; + + dep_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT; + dep_req->cmd = DIGITAL_CMD_DEP_REQ; + dep_req->pfb = DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU | + DIGITAL_NFC_DEP_PFB_TIMEOUT_BIT; + + digital_skb_push_dep_sod(ddev, skb); + + ddev->skb_add_crc(skb); + + rc = digital_in_send_cmd(ddev, skb, rwt_int, + digital_in_recv_dep_res, data_exch); + if (rc) + kfree_skb(skb); + + return rc; +} + +static int digital_in_send_saved_skb(struct nfc_digital_dev *ddev, + struct digital_data_exch *data_exch) +{ + int rc; + + if (!ddev->saved_skb) + return -EINVAL; + + skb_get(ddev->saved_skb); + + rc = digital_in_send_cmd(ddev, ddev->saved_skb, ddev->dep_rwt, + digital_in_recv_dep_res, data_exch); + if (rc) + kfree_skb(ddev->saved_skb); + + return rc; +} + +static void digital_in_recv_dep_res(struct nfc_digital_dev *ddev, void *arg, + struct sk_buff *resp) +{ + struct digital_data_exch *data_exch = arg; + struct digital_dep_req_res *dep_res; + u8 pfb; + uint size; + int rc; + u8 rtox; + + if (IS_ERR(resp)) { + rc = PTR_ERR(resp); + resp = NULL; + + if ((rc == -EIO || (rc == -ETIMEDOUT && ddev->nack_count)) && + (ddev->nack_count++ < DIGITAL_NFC_DEP_N_RETRY_NACK)) { + ddev->atn_count = 0; + + rc = digital_in_send_nack(ddev, data_exch); + if (rc) + goto error; + + return; + } else if ((rc == -ETIMEDOUT) && + (ddev->atn_count++ < DIGITAL_NFC_DEP_N_RETRY_ATN)) { + ddev->nack_count = 0; + + rc = digital_in_send_atn(ddev, data_exch); + if (rc) + goto error; + + return; + } + + goto exit; + } + + rc = digital_skb_pull_dep_sod(ddev, resp); + if (rc) { + PROTOCOL_ERR("14.4.1.2"); + goto exit; + } + + rc = ddev->skb_check_crc(resp); + if (rc) { + if ((resp->len >= 4) && + (ddev->nack_count++ < DIGITAL_NFC_DEP_N_RETRY_NACK)) { + ddev->atn_count = 0; + + rc = digital_in_send_nack(ddev, data_exch); + if (rc) + goto error; + + kfree_skb(resp); + + return; + } + + PROTOCOL_ERR("14.4.1.6"); + goto error; + } + + ddev->atn_count = 0; + ddev->nack_count = 0; + + if (resp->len > ddev->local_payload_max) { + rc = -EMSGSIZE; + goto exit; + } + + size = sizeof(struct digital_dep_req_res); + dep_res = (struct digital_dep_req_res *)resp->data; + + if (resp->len < size || dep_res->dir != DIGITAL_NFC_DEP_FRAME_DIR_IN || + dep_res->cmd != DIGITAL_CMD_DEP_RES) { + rc = -EIO; + goto error; + } + + pfb = dep_res->pfb; + + if (DIGITAL_NFC_DEP_DID_BIT_SET(pfb)) { + PROTOCOL_ERR("14.8.2.1"); + rc = -EIO; + goto error; + } + + if (DIGITAL_NFC_DEP_NAD_BIT_SET(pfb)) { + rc = -EIO; + goto exit; + } + + if (size > resp->len) { + rc = -EIO; + goto error; + } + + skb_pull(resp, size); + + switch (DIGITAL_NFC_DEP_PFB_TYPE(pfb)) { + case DIGITAL_NFC_DEP_PFB_I_PDU: + if (DIGITAL_NFC_DEP_PFB_PNI(pfb) != ddev->curr_nfc_dep_pni) { + PROTOCOL_ERR("14.12.3.3"); + rc = -EIO; + goto error; + } + + ddev->curr_nfc_dep_pni = + DIGITAL_NFC_DEP_PFB_PNI(ddev->curr_nfc_dep_pni + 1); + + kfree_skb(ddev->saved_skb); + ddev->saved_skb = NULL; + + resp = digital_recv_dep_data_gather(ddev, pfb, resp, + digital_in_send_ack, + data_exch); + if (IS_ERR(resp)) { + rc = PTR_ERR(resp); + resp = NULL; + goto error; + } + + /* If resp is NULL then we're still chaining so return and + * wait for the next part of the PDU. Else, the PDU is + * complete so pass it up. + */ + if (!resp) + return; + + rc = 0; + break; + + case DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU: + if (DIGITAL_NFC_DEP_NACK_BIT_SET(pfb)) { + PROTOCOL_ERR("14.12.4.5"); + rc = -EIO; + goto exit; + } + + if (DIGITAL_NFC_DEP_PFB_PNI(pfb) != ddev->curr_nfc_dep_pni) { + PROTOCOL_ERR("14.12.3.3"); + rc = -EIO; + goto exit; + } + + ddev->curr_nfc_dep_pni = + DIGITAL_NFC_DEP_PFB_PNI(ddev->curr_nfc_dep_pni + 1); + + if (!ddev->chaining_skb) { + PROTOCOL_ERR("14.12.4.3"); + rc = -EIO; + goto exit; + } + + /* The initiator has received a valid ACK. Free the last sent + * PDU and keep on sending chained skb. + */ + kfree_skb(ddev->saved_skb); + ddev->saved_skb = NULL; + + rc = digital_in_send_dep_req(ddev, NULL, + ddev->chaining_skb, + ddev->data_exch); + if (rc) + goto error; + + goto free_resp; + + case DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU: + if (!DIGITAL_NFC_DEP_PFB_IS_TIMEOUT(pfb)) { /* ATN */ + rc = digital_in_send_saved_skb(ddev, data_exch); + if (rc) + goto error; + + goto free_resp; + } + + if (ddev->atn_count || ddev->nack_count) { + PROTOCOL_ERR("14.12.4.4"); + rc = -EIO; + goto error; + } + + rtox = DIGITAL_NFC_DEP_RTOX_VALUE(resp->data[0]); + if (!rtox || rtox > DIGITAL_NFC_DEP_RTOX_MAX) { + PROTOCOL_ERR("14.8.4.1"); + rc = -EIO; + goto error; + } + + rc = digital_in_send_rtox(ddev, data_exch, rtox); + if (rc) + goto error; + + goto free_resp; + } + +exit: + data_exch->cb(data_exch->cb_context, resp, rc); + +error: + kfree(data_exch); + + kfree_skb(ddev->chaining_skb); + ddev->chaining_skb = NULL; + + kfree_skb(ddev->saved_skb); + ddev->saved_skb = NULL; + + if (rc) + kfree_skb(resp); + + return; + +free_resp: + dev_kfree_skb(resp); +} + +int digital_in_send_dep_req(struct nfc_digital_dev *ddev, + struct nfc_target *target, struct sk_buff *skb, + struct digital_data_exch *data_exch) +{ + struct digital_dep_req_res *dep_req; + struct sk_buff *chaining_skb, *tmp_skb; + int rc; + + skb_push(skb, sizeof(struct digital_dep_req_res)); + + dep_req = (struct digital_dep_req_res *)skb->data; + + dep_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT; + dep_req->cmd = DIGITAL_CMD_DEP_REQ; + dep_req->pfb = ddev->curr_nfc_dep_pni; + + ddev->atn_count = 0; + ddev->nack_count = 0; + + chaining_skb = ddev->chaining_skb; + + tmp_skb = digital_send_dep_data_prep(ddev, skb, dep_req, data_exch); + if (IS_ERR(tmp_skb)) + return PTR_ERR(tmp_skb); + + digital_skb_push_dep_sod(ddev, tmp_skb); + + ddev->skb_add_crc(tmp_skb); + + ddev->saved_skb = pskb_copy(tmp_skb, GFP_KERNEL); + + rc = digital_in_send_cmd(ddev, tmp_skb, ddev->dep_rwt, + digital_in_recv_dep_res, data_exch); + if (rc) { + if (tmp_skb != skb) + kfree_skb(tmp_skb); + + kfree_skb(chaining_skb); + ddev->chaining_skb = NULL; + + kfree_skb(ddev->saved_skb); + ddev->saved_skb = NULL; + } + + return rc; +} + +static void digital_tg_set_rf_tech(struct nfc_digital_dev *ddev, u8 rf_tech) +{ + ddev->curr_rf_tech = rf_tech; + + ddev->skb_add_crc = digital_skb_add_crc_none; + ddev->skb_check_crc = digital_skb_check_crc_none; + + if (DIGITAL_DRV_CAPS_TG_CRC(ddev)) + return; + + switch (ddev->curr_rf_tech) { + case NFC_DIGITAL_RF_TECH_106A: + ddev->skb_add_crc = digital_skb_add_crc_a; + ddev->skb_check_crc = digital_skb_check_crc_a; + break; + + case NFC_DIGITAL_RF_TECH_212F: + case NFC_DIGITAL_RF_TECH_424F: + ddev->skb_add_crc = digital_skb_add_crc_f; + ddev->skb_check_crc = digital_skb_check_crc_f; + break; + + default: + break; + } +} + +static int digital_tg_send_ack(struct nfc_digital_dev *ddev, + struct digital_data_exch *data_exch) +{ + struct digital_dep_req_res *dep_res; + struct sk_buff *skb; + int rc; + + skb = digital_skb_alloc(ddev, 1); + if (!skb) + return -ENOMEM; + + skb_push(skb, sizeof(struct digital_dep_req_res)); + + dep_res = (struct digital_dep_req_res *)skb->data; + + dep_res->dir = DIGITAL_NFC_DEP_FRAME_DIR_IN; + dep_res->cmd = DIGITAL_CMD_DEP_RES; + dep_res->pfb = DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU | + ddev->curr_nfc_dep_pni; + + if (ddev->did) { + dep_res->pfb |= DIGITAL_NFC_DEP_PFB_DID_BIT; + + skb_put_data(skb, &ddev->did, sizeof(ddev->did)); + } + + ddev->curr_nfc_dep_pni = + DIGITAL_NFC_DEP_PFB_PNI(ddev->curr_nfc_dep_pni + 1); + + digital_skb_push_dep_sod(ddev, skb); + + ddev->skb_add_crc(skb); + + ddev->saved_skb = pskb_copy(skb, GFP_KERNEL); + + rc = digital_tg_send_cmd(ddev, skb, 1500, digital_tg_recv_dep_req, + data_exch); + if (rc) { + kfree_skb(skb); + kfree_skb(ddev->saved_skb); + ddev->saved_skb = NULL; + } + + return rc; +} + +static int digital_tg_send_atn(struct nfc_digital_dev *ddev) +{ + struct digital_dep_req_res *dep_res; + struct sk_buff *skb; + int rc; + + skb = digital_skb_alloc(ddev, 1); + if (!skb) + return -ENOMEM; + + skb_push(skb, sizeof(struct digital_dep_req_res)); + + dep_res = (struct digital_dep_req_res *)skb->data; + + dep_res->dir = DIGITAL_NFC_DEP_FRAME_DIR_IN; + dep_res->cmd = DIGITAL_CMD_DEP_RES; + dep_res->pfb = DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU; + + if (ddev->did) { + dep_res->pfb |= DIGITAL_NFC_DEP_PFB_DID_BIT; + + skb_put_data(skb, &ddev->did, sizeof(ddev->did)); + } + + digital_skb_push_dep_sod(ddev, skb); + + ddev->skb_add_crc(skb); + + rc = digital_tg_send_cmd(ddev, skb, 1500, digital_tg_recv_dep_req, + NULL); + if (rc) + kfree_skb(skb); + + return rc; +} + +static int digital_tg_send_saved_skb(struct nfc_digital_dev *ddev) +{ + int rc; + + if (!ddev->saved_skb) + return -EINVAL; + + skb_get(ddev->saved_skb); + + rc = digital_tg_send_cmd(ddev, ddev->saved_skb, 1500, + digital_tg_recv_dep_req, NULL); + if (rc) + kfree_skb(ddev->saved_skb); + + return rc; +} + +static void digital_tg_recv_dep_req(struct nfc_digital_dev *ddev, void *arg, + struct sk_buff *resp) +{ + int rc; + struct digital_dep_req_res *dep_req; + u8 pfb; + size_t size; + + if (IS_ERR(resp)) { + rc = PTR_ERR(resp); + resp = NULL; + goto exit; + } + + rc = ddev->skb_check_crc(resp); + if (rc) { + PROTOCOL_ERR("14.4.1.6"); + goto exit; + } + + rc = digital_skb_pull_dep_sod(ddev, resp); + if (rc) { + PROTOCOL_ERR("14.4.1.2"); + goto exit; + } + + if (resp->len > ddev->local_payload_max) { + rc = -EMSGSIZE; + goto exit; + } + + size = sizeof(struct digital_dep_req_res); + dep_req = (struct digital_dep_req_res *)resp->data; + + if (resp->len < size || dep_req->dir != DIGITAL_NFC_DEP_FRAME_DIR_OUT || + dep_req->cmd != DIGITAL_CMD_DEP_REQ) { + rc = -EIO; + goto exit; + } + + pfb = dep_req->pfb; + + if (DIGITAL_NFC_DEP_DID_BIT_SET(pfb)) { + if (ddev->did && (ddev->did == resp->data[3])) { + size++; + } else { + rc = -EIO; + goto exit; + } + } else if (ddev->did) { + rc = -EIO; + goto exit; + } + + if (DIGITAL_NFC_DEP_NAD_BIT_SET(pfb)) { + rc = -EIO; + goto exit; + } + + if (size > resp->len) { + rc = -EIO; + goto exit; + } + + skb_pull(resp, size); + + switch (DIGITAL_NFC_DEP_PFB_TYPE(pfb)) { + case DIGITAL_NFC_DEP_PFB_I_PDU: + pr_debug("DIGITAL_NFC_DEP_PFB_I_PDU\n"); + + if (ddev->atn_count) { + /* The target has received (and replied to) at least one + * ATN DEP_REQ. + */ + ddev->atn_count = 0; + + /* pni of resp PDU equal to the target current pni - 1 + * means resp is the previous DEP_REQ PDU received from + * the initiator so the target replies with saved_skb + * which is the previous DEP_RES saved in + * digital_tg_send_dep_res(). + */ + if (DIGITAL_NFC_DEP_PFB_PNI(pfb) == + DIGITAL_NFC_DEP_PFB_PNI(ddev->curr_nfc_dep_pni - 1)) { + rc = digital_tg_send_saved_skb(ddev); + if (rc) + goto exit; + + goto free_resp; + } + + /* atn_count > 0 and PDU pni != curr_nfc_dep_pni - 1 + * means the target probably did not received the last + * DEP_REQ PDU sent by the initiator. The target + * fallbacks to normal processing then. + */ + } + + if (DIGITAL_NFC_DEP_PFB_PNI(pfb) != ddev->curr_nfc_dep_pni) { + PROTOCOL_ERR("14.12.3.4"); + rc = -EIO; + goto exit; + } + + kfree_skb(ddev->saved_skb); + ddev->saved_skb = NULL; + + resp = digital_recv_dep_data_gather(ddev, pfb, resp, + digital_tg_send_ack, NULL); + if (IS_ERR(resp)) { + rc = PTR_ERR(resp); + resp = NULL; + goto exit; + } + + /* If resp is NULL then we're still chaining so return and + * wait for the next part of the PDU. Else, the PDU is + * complete so pass it up. + */ + if (!resp) + return; + + rc = 0; + break; + case DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU: + if (DIGITAL_NFC_DEP_NACK_BIT_SET(pfb)) { /* NACK */ + if (DIGITAL_NFC_DEP_PFB_PNI(pfb + 1) != + ddev->curr_nfc_dep_pni) { + rc = -EIO; + goto exit; + } + + ddev->atn_count = 0; + + rc = digital_tg_send_saved_skb(ddev); + if (rc) + goto exit; + + goto free_resp; + } + + /* ACK */ + if (ddev->atn_count) { + /* The target has previously recevied one or more ATN + * PDUs. + */ + ddev->atn_count = 0; + + /* If the ACK PNI is equal to the target PNI - 1 means + * that the initiator did not receive the previous PDU + * sent by the target so re-send it. + */ + if (DIGITAL_NFC_DEP_PFB_PNI(pfb + 1) == + ddev->curr_nfc_dep_pni) { + rc = digital_tg_send_saved_skb(ddev); + if (rc) + goto exit; + + goto free_resp; + } + + /* Otherwise, the target did not receive the previous + * ACK PDU from the initiator. Fallback to normal + * processing of chained PDU then. + */ + } + + /* Keep on sending chained PDU */ + if (!ddev->chaining_skb || + DIGITAL_NFC_DEP_PFB_PNI(pfb) != + ddev->curr_nfc_dep_pni) { + rc = -EIO; + goto exit; + } + + kfree_skb(ddev->saved_skb); + ddev->saved_skb = NULL; + + rc = digital_tg_send_dep_res(ddev, ddev->chaining_skb); + if (rc) + goto exit; + + goto free_resp; + case DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU: + if (DIGITAL_NFC_DEP_PFB_IS_TIMEOUT(pfb)) { + rc = -EINVAL; + goto exit; + } + + rc = digital_tg_send_atn(ddev); + if (rc) + goto exit; + + ddev->atn_count++; + + goto free_resp; + } + + rc = nfc_tm_data_received(ddev->nfc_dev, resp); + if (rc) + resp = NULL; + +exit: + kfree_skb(ddev->chaining_skb); + ddev->chaining_skb = NULL; + + ddev->atn_count = 0; + + kfree_skb(ddev->saved_skb); + ddev->saved_skb = NULL; + + if (rc) + kfree_skb(resp); + + return; + +free_resp: + dev_kfree_skb(resp); +} + +int digital_tg_send_dep_res(struct nfc_digital_dev *ddev, struct sk_buff *skb) +{ + struct digital_dep_req_res *dep_res; + struct sk_buff *chaining_skb, *tmp_skb; + int rc; + + skb_push(skb, sizeof(struct digital_dep_req_res)); + + dep_res = (struct digital_dep_req_res *)skb->data; + + dep_res->dir = DIGITAL_NFC_DEP_FRAME_DIR_IN; + dep_res->cmd = DIGITAL_CMD_DEP_RES; + dep_res->pfb = ddev->curr_nfc_dep_pni; + + if (ddev->did) { + dep_res->pfb |= DIGITAL_NFC_DEP_PFB_DID_BIT; + + skb_put_data(skb, &ddev->did, sizeof(ddev->did)); + } + + ddev->curr_nfc_dep_pni = + DIGITAL_NFC_DEP_PFB_PNI(ddev->curr_nfc_dep_pni + 1); + + chaining_skb = ddev->chaining_skb; + + tmp_skb = digital_send_dep_data_prep(ddev, skb, dep_res, NULL); + if (IS_ERR(tmp_skb)) + return PTR_ERR(tmp_skb); + + digital_skb_push_dep_sod(ddev, tmp_skb); + + ddev->skb_add_crc(tmp_skb); + + ddev->saved_skb = pskb_copy(tmp_skb, GFP_KERNEL); + + rc = digital_tg_send_cmd(ddev, tmp_skb, 1500, digital_tg_recv_dep_req, + NULL); + if (rc) { + if (tmp_skb != skb) + kfree_skb(tmp_skb); + + kfree_skb(chaining_skb); + ddev->chaining_skb = NULL; + + kfree_skb(ddev->saved_skb); + ddev->saved_skb = NULL; + } + + return rc; +} + +static void digital_tg_send_psl_res_complete(struct nfc_digital_dev *ddev, + void *arg, struct sk_buff *resp) +{ + u8 rf_tech = (unsigned long)arg; + + if (IS_ERR(resp)) + return; + + digital_tg_set_rf_tech(ddev, rf_tech); + + digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH, rf_tech); + + digital_tg_listen(ddev, 1500, digital_tg_recv_dep_req, NULL); + + dev_kfree_skb(resp); +} + +static int digital_tg_send_psl_res(struct nfc_digital_dev *ddev, u8 did, + u8 rf_tech) +{ + struct digital_psl_res *psl_res; + struct sk_buff *skb; + int rc; + + skb = digital_skb_alloc(ddev, sizeof(struct digital_psl_res)); + if (!skb) + return -ENOMEM; + + skb_put(skb, sizeof(struct digital_psl_res)); + + psl_res = (struct digital_psl_res *)skb->data; + + psl_res->dir = DIGITAL_NFC_DEP_FRAME_DIR_IN; + psl_res->cmd = DIGITAL_CMD_PSL_RES; + psl_res->did = did; + + digital_skb_push_dep_sod(ddev, skb); + + ddev->skb_add_crc(skb); + + ddev->curr_nfc_dep_pni = 0; + + rc = digital_tg_send_cmd(ddev, skb, 0, digital_tg_send_psl_res_complete, + (void *)(unsigned long)rf_tech); + if (rc) + kfree_skb(skb); + + return rc; +} + +static void digital_tg_recv_psl_req(struct nfc_digital_dev *ddev, void *arg, + struct sk_buff *resp) +{ + int rc; + struct digital_psl_req *psl_req; + u8 rf_tech; + u8 dsi, payload_size, payload_bits; + + if (IS_ERR(resp)) { + rc = PTR_ERR(resp); + resp = NULL; + goto exit; + } + + rc = ddev->skb_check_crc(resp); + if (rc) { + PROTOCOL_ERR("14.4.1.6"); + goto exit; + } + + rc = digital_skb_pull_dep_sod(ddev, resp); + if (rc) { + PROTOCOL_ERR("14.4.1.2"); + goto exit; + } + + psl_req = (struct digital_psl_req *)resp->data; + + if (resp->len != sizeof(struct digital_psl_req) || + psl_req->dir != DIGITAL_NFC_DEP_FRAME_DIR_OUT || + psl_req->cmd != DIGITAL_CMD_PSL_REQ) { + rc = -EIO; + goto exit; + } + + dsi = (psl_req->brs >> 3) & 0x07; + switch (dsi) { + case 0: + rf_tech = NFC_DIGITAL_RF_TECH_106A; + break; + case 1: + rf_tech = NFC_DIGITAL_RF_TECH_212F; + break; + case 2: + rf_tech = NFC_DIGITAL_RF_TECH_424F; + break; + default: + pr_err("Unsupported dsi value %d\n", dsi); + goto exit; + } + + payload_bits = DIGITAL_PAYLOAD_FSL_TO_BITS(psl_req->fsl); + payload_size = digital_payload_bits_to_size(payload_bits); + + if (!payload_size || (payload_size > min(ddev->local_payload_max, + ddev->remote_payload_max))) { + rc = -EINVAL; + goto exit; + } + + ddev->local_payload_max = payload_size; + ddev->remote_payload_max = payload_size; + + rc = digital_tg_send_psl_res(ddev, psl_req->did, rf_tech); + +exit: + kfree_skb(resp); +} + +static void digital_tg_send_atr_res_complete(struct nfc_digital_dev *ddev, + void *arg, struct sk_buff *resp) +{ + int offset; + + if (IS_ERR(resp)) { + digital_poll_next_tech(ddev); + return; + } + + offset = 2; + if (resp->data[0] == DIGITAL_NFC_DEP_NFCA_SOD_SB) + offset++; + + ddev->atn_count = 0; + + if (resp->data[offset] == DIGITAL_CMD_PSL_REQ) + digital_tg_recv_psl_req(ddev, arg, resp); + else + digital_tg_recv_dep_req(ddev, arg, resp); +} + +static int digital_tg_send_atr_res(struct nfc_digital_dev *ddev, + struct digital_atr_req *atr_req) +{ + struct digital_atr_res *atr_res; + struct sk_buff *skb; + u8 *gb, payload_bits; + size_t gb_len; + int rc; + + gb = nfc_get_local_general_bytes(ddev->nfc_dev, &gb_len); + if (!gb) + gb_len = 0; + + skb = digital_skb_alloc(ddev, sizeof(struct digital_atr_res) + gb_len); + if (!skb) + return -ENOMEM; + + skb_put(skb, sizeof(struct digital_atr_res)); + atr_res = (struct digital_atr_res *)skb->data; + + memset(atr_res, 0, sizeof(struct digital_atr_res)); + + atr_res->dir = DIGITAL_NFC_DEP_FRAME_DIR_IN; + atr_res->cmd = DIGITAL_CMD_ATR_RES; + memcpy(atr_res->nfcid3, atr_req->nfcid3, sizeof(atr_req->nfcid3)); + atr_res->to = DIGITAL_NFC_DEP_TG_MAX_WT; + + ddev->local_payload_max = DIGITAL_PAYLOAD_SIZE_MAX; + payload_bits = digital_payload_size_to_bits(ddev->local_payload_max); + atr_res->pp = DIGITAL_PAYLOAD_BITS_TO_PP(payload_bits); + + if (gb_len) { + skb_put(skb, gb_len); + + atr_res->pp |= DIGITAL_GB_BIT; + memcpy(atr_res->gb, gb, gb_len); + } + + digital_skb_push_dep_sod(ddev, skb); + + ddev->skb_add_crc(skb); + + ddev->curr_nfc_dep_pni = 0; + + rc = digital_tg_send_cmd(ddev, skb, 999, + digital_tg_send_atr_res_complete, NULL); + if (rc) + kfree_skb(skb); + + return rc; +} + +void digital_tg_recv_atr_req(struct nfc_digital_dev *ddev, void *arg, + struct sk_buff *resp) +{ + int rc; + struct digital_atr_req *atr_req; + size_t gb_len, min_size; + u8 poll_tech_count, payload_bits; + + if (IS_ERR(resp)) { + rc = PTR_ERR(resp); + resp = NULL; + goto exit; + } + + if (!resp->len) { + rc = -EIO; + goto exit; + } + + if (resp->data[0] == DIGITAL_NFC_DEP_NFCA_SOD_SB) { + min_size = DIGITAL_ATR_REQ_MIN_SIZE + 2; + digital_tg_set_rf_tech(ddev, NFC_DIGITAL_RF_TECH_106A); + } else { + min_size = DIGITAL_ATR_REQ_MIN_SIZE + 1; + digital_tg_set_rf_tech(ddev, NFC_DIGITAL_RF_TECH_212F); + } + + if (resp->len < min_size) { + rc = -EIO; + goto exit; + } + + ddev->curr_protocol = NFC_PROTO_NFC_DEP_MASK; + + rc = ddev->skb_check_crc(resp); + if (rc) { + PROTOCOL_ERR("14.4.1.6"); + goto exit; + } + + rc = digital_skb_pull_dep_sod(ddev, resp); + if (rc) { + PROTOCOL_ERR("14.4.1.2"); + goto exit; + } + + atr_req = (struct digital_atr_req *)resp->data; + + if (atr_req->dir != DIGITAL_NFC_DEP_FRAME_DIR_OUT || + atr_req->cmd != DIGITAL_CMD_ATR_REQ || + atr_req->did > DIGITAL_DID_MAX) { + rc = -EINVAL; + goto exit; + } + + payload_bits = DIGITAL_PAYLOAD_PP_TO_BITS(atr_req->pp); + ddev->remote_payload_max = digital_payload_bits_to_size(payload_bits); + + if (!ddev->remote_payload_max) { + rc = -EINVAL; + goto exit; + } + + ddev->did = atr_req->did; + + rc = digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING, + NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED); + if (rc) + goto exit; + + rc = digital_tg_send_atr_res(ddev, atr_req); + if (rc) + goto exit; + + gb_len = resp->len - sizeof(struct digital_atr_req); + + poll_tech_count = ddev->poll_tech_count; + ddev->poll_tech_count = 0; + + rc = nfc_tm_activated(ddev->nfc_dev, NFC_PROTO_NFC_DEP_MASK, + NFC_COMM_PASSIVE, atr_req->gb, gb_len); + if (rc) { + ddev->poll_tech_count = poll_tech_count; + goto exit; + } + + rc = 0; +exit: + if (rc) + digital_poll_next_tech(ddev); + + dev_kfree_skb(resp); +} -- cgit v1.2.3