NFC: digital: Add NFC-DEP Target-side ATN Support

When an NFC-DEP target receives an ATN PDU, its
supposed to respond with a similar ATN PDU.
When the Target receives an I PDU with the PNI
one less than the current PNI and the last PDU
sent was an ATN PDU, the Target is to resend the
last non-ATN PDU that it has sent.  This is
described in section 14.12.3.4 of the NFC Digital
Protocol Spec.

The digital layer's NFC-DEP code doesn't implement
this so add that support.

Reviewed-by: Thierry Escande <thierry.escande@linux.intel.com>
Tested-by: Thierry Escande <thierry.escande@linux.intel.com>
Signed-off-by: Mark A. Greer <mgreer@animalcreek.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
This commit is contained in:
Mark A. Greer 2014-09-23 16:38:14 -07:00 committed by Samuel Ortiz
parent 384ab1d174
commit 9b5ec0fd58

View file

@ -970,6 +970,43 @@ static int digital_tg_send_ack(struct nfc_digital_dev *ddev,
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;
memcpy(skb_put(skb, sizeof(ddev->did)), &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)
{
skb_get(ddev->saved_skb);
@ -1049,12 +1086,24 @@ static void digital_tg_recv_dep_req(struct nfc_digital_dev *ddev, void *arg,
case DIGITAL_NFC_DEP_PFB_I_PDU:
pr_debug("DIGITAL_NFC_DEP_PFB_I_PDU\n");
if (DIGITAL_NFC_DEP_PFB_PNI(pfb) != ddev->curr_nfc_dep_pni) {
if ((ddev->atn_count && (DIGITAL_NFC_DEP_PFB_PNI(pfb - 1) !=
ddev->curr_nfc_dep_pni)) ||
(DIGITAL_NFC_DEP_PFB_PNI(pfb) != ddev->curr_nfc_dep_pni)) {
PROTOCOL_ERR("14.12.3.4");
rc = -EIO;
goto exit;
}
if (ddev->atn_count) {
ddev->atn_count = 0;
rc = digital_tg_send_saved_skb(ddev);
if (rc)
goto exit;
return;
}
kfree_skb(ddev->saved_skb);
ddev->saved_skb = NULL;
@ -1077,13 +1126,26 @@ static void digital_tg_recv_dep_req(struct nfc_digital_dev *ddev, void *arg,
break;
case DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU:
if (!DIGITAL_NFC_DEP_NACK_BIT_SET(pfb)) { /* ACK */
if ((DIGITAL_NFC_DEP_PFB_PNI(pfb) !=
if ((ddev->atn_count &&
(DIGITAL_NFC_DEP_PFB_PNI(pfb - 1) !=
ddev->curr_nfc_dep_pni)) ||
(DIGITAL_NFC_DEP_PFB_PNI(pfb) !=
ddev->curr_nfc_dep_pni) ||
!ddev->chaining_skb || !ddev->saved_skb) {
rc = -EIO;
goto exit;
}
if (ddev->atn_count) {
ddev->atn_count = 0;
rc = digital_tg_send_saved_skb(ddev);
if (rc)
goto exit;
return;
}
kfree_skb(ddev->saved_skb);
ddev->saved_skb = NULL;
@ -1098,6 +1160,8 @@ static void digital_tg_recv_dep_req(struct nfc_digital_dev *ddev, void *arg,
goto exit;
}
ddev->atn_count = 0;
rc = digital_tg_send_saved_skb(ddev);
if (rc) {
kfree_skb(ddev->saved_skb);
@ -1107,9 +1171,19 @@ static void digital_tg_recv_dep_req(struct nfc_digital_dev *ddev, void *arg,
return;
case DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU:
pr_err("Received a SUPERVISOR PDU\n");
rc = -EINVAL;
goto exit;
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++;
kfree_skb(resp);
return;
}
rc = nfc_tm_data_received(ddev->nfc_dev, resp);
@ -1118,6 +1192,8 @@ static void digital_tg_recv_dep_req(struct nfc_digital_dev *ddev, void *arg,
kfree_skb(ddev->chaining_skb);
ddev->chaining_skb = NULL;
ddev->atn_count = 0;
kfree_skb(ddev->saved_skb);
ddev->saved_skb = NULL;
@ -1311,6 +1387,8 @@ static void digital_tg_send_atr_res_complete(struct nfc_digital_dev *ddev,
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