NFC: DEP link hook implementation for pn533

Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/drivers/nfc/pn533.c b/drivers/nfc/pn533.c
index dccd965..b8b6c2a 100644 (file)
--- a/drivers/nfc/pn533.c
+++ b/drivers/nfc/pn533.c
@@ -72,6 +72,7 @@ MODULE_DEVICE_TABLE(usb, pn533_table);
 #define PN533_CMD_IN_LIST_PASSIVE_TARGET 0x4A
 #define PN533_CMD_IN_ATR 0x50
 #define PN533_CMD_IN_RELEASE 0x52
+#define PN533_CMD_IN_JUMP_FOR_DEP 0x56
 
 #define PN533_CMD_RESPONSE(cmd) (cmd + 1)
 
@@ -231,6 +232,26 @@ struct pn533_cmd_activate_response {
        u8 gt[];
 } __packed;
 
+/* PN533_CMD_IN_JUMP_FOR_DEP */
+struct pn533_cmd_jump_dep {
+       u8 active;
+       u8 baud;
+       u8 next;
+       u8 gt[];
+} __packed;
+
+struct pn533_cmd_jump_dep_response {
+       u8 status;
+       u8 tg;
+       u8 nfcid3t[10];
+       u8 didt;
+       u8 bst;
+       u8 brt;
+       u8 to;
+       u8 ppt;
+       /* optional */
+       u8 gt[];
+} __packed;
 
 struct pn533 {
        struct usb_device *udev;
@@ -1244,6 +1265,142 @@ static void pn533_deactivate_target(struct nfc_dev *nfc_dev, u32 target_idx)
        return;
 }
 
+
+static int pn533_in_dep_link_up_complete(struct pn533 *dev, void *arg,
+                                               u8 *params, int params_len)
+{
+       struct pn533_cmd_jump_dep *cmd;
+       struct pn533_cmd_jump_dep_response *resp;
+       struct nfc_target nfc_target;
+       u8 target_gt_len;
+       int rc;
+
+       if (params_len == -ENOENT) {
+               nfc_dev_dbg(&dev->interface->dev, "");
+               return 0;
+       }
+
+       if (params_len < 0) {
+               nfc_dev_err(&dev->interface->dev,
+                               "Error %d when bringing DEP link up",
+                                                               params_len);
+               return 0;
+       }
+
+       if (dev->tgt_available_prots &&
+           !(dev->tgt_available_prots & (1 << NFC_PROTO_NFC_DEP))) {
+               nfc_dev_err(&dev->interface->dev,
+                       "The target does not support DEP");
+               return -EINVAL;
+       }
+
+       resp = (struct pn533_cmd_jump_dep_response *) params;
+       cmd = (struct pn533_cmd_jump_dep *) arg;
+       rc = resp->status & PN533_CMD_RET_MASK;
+       if (rc != PN533_CMD_RET_SUCCESS) {
+               nfc_dev_err(&dev->interface->dev,
+                               "Bringing DEP link up failed %d", rc);
+               return 0;
+       }
+
+       if (!dev->tgt_available_prots) {
+               nfc_dev_dbg(&dev->interface->dev, "Creating new target");
+
+               nfc_target.supported_protocols = NFC_PROTO_NFC_DEP_MASK;
+               rc = nfc_targets_found(dev->nfc_dev, &nfc_target, 1);
+               if (rc)
+                       return 0;
+
+               dev->tgt_available_prots = 0;
+       }
+
+       dev->tgt_active_prot = NFC_PROTO_NFC_DEP;
+
+       /* ATR_RES general bytes are located at offset 17 */
+       target_gt_len = PN533_FRAME_CMD_PARAMS_LEN(dev->in_frame) - 17;
+       rc = nfc_set_remote_general_bytes(dev->nfc_dev,
+                                               resp->gt, target_gt_len);
+       if (rc == 0)
+               rc = nfc_dep_link_is_up(dev->nfc_dev,
+                                               dev->nfc_dev->targets[0].idx,
+                                               !cmd->active, NFC_RF_INITIATOR);
+
+       return 0;
+}
+
+static int pn533_dep_link_up(struct nfc_dev *nfc_dev, int target_idx,
+                                               u8 comm_mode, u8 rf_mode)
+{
+       struct pn533 *dev = nfc_get_drvdata(nfc_dev);
+       struct pn533_cmd_jump_dep *cmd;
+       u8 cmd_len, local_gt_len, *local_gt;
+       int rc;
+
+       nfc_dev_dbg(&dev->interface->dev, "%s", __func__);
+
+       if (rf_mode == NFC_RF_TARGET) {
+               nfc_dev_err(&dev->interface->dev, "Target mode not supported");
+               return -EOPNOTSUPP;
+       }
+
+
+       if (dev->poll_mod_count) {
+               nfc_dev_err(&dev->interface->dev,
+                               "Cannot bring the DEP link up while polling");
+               return -EBUSY;
+       }
+
+       if (dev->tgt_active_prot) {
+               nfc_dev_err(&dev->interface->dev,
+                               "There is already an active target");
+               return -EBUSY;
+       }
+
+       local_gt = nfc_get_local_general_bytes(dev->nfc_dev, &local_gt_len);
+       if (local_gt_len > NFC_MAX_GT_LEN)
+               return -EINVAL;
+
+       cmd_len = sizeof(struct pn533_cmd_jump_dep) + local_gt_len;
+       cmd = kzalloc(cmd_len, GFP_KERNEL);
+       if (cmd == NULL)
+               return -ENOMEM;
+
+       pn533_tx_frame_init(dev->out_frame, PN533_CMD_IN_JUMP_FOR_DEP);
+
+       cmd->active = !comm_mode;
+       cmd->baud = 0;
+       if (local_gt != NULL) {
+               cmd->next = 4; /* We have some Gi */
+               memcpy(cmd->gt, local_gt, local_gt_len);
+       } else {
+               cmd->next = 0;
+       }
+
+       memcpy(PN533_FRAME_CMD_PARAMS_PTR(dev->out_frame), cmd, cmd_len);
+       dev->out_frame->datalen += cmd_len;
+
+       pn533_tx_frame_finish(dev->out_frame);
+
+       rc = pn533_send_cmd_frame_async(dev, dev->out_frame, dev->in_frame,
+                               dev->in_maxlen, pn533_in_dep_link_up_complete,
+                               cmd, GFP_KERNEL);
+       if (rc)
+               goto out;
+
+
+out:
+       kfree(cmd);
+
+       return rc;
+}
+
+static int pn533_dep_link_down(struct nfc_dev *nfc_dev)
+{
+       pn533_deactivate_target(nfc_dev, 0);
+
+       return 0;
+}
+
 #define PN533_CMD_DATAEXCH_HEAD_LEN (sizeof(struct pn533_frame) + 3)
 #define PN533_CMD_DATAEXCH_DATA_MAXLEN 262
 
@@ -1439,6 +1596,8 @@ static int pn533_set_configuration(struct pn533 *dev, u8 cfgitem, u8 *cfgdata,
 struct nfc_ops pn533_nfc_ops = {
        .dev_up = NULL,
        .dev_down = NULL,
+       .dep_link_up = pn533_dep_link_up,
+       .dep_link_down = pn533_dep_link_down,
        .start_poll = pn533_start_poll,
        .stop_poll = pn533_stop_poll,
        .activate_target = pn533_activate_target,