From 963a82e07d4e1f95fc423d53912ac0a7fe643b1c Mon Sep 17 00:00:00 2001 From: Olivier Guiter Date: Thu, 13 Jun 2013 13:43:28 +0000 Subject: [PATCH] NFC: pn533: Split large Tx frames in chunks On sending large frames (size > 262), we split it in multiple chunks and send them asynchronously with MI bit. Signed-off-by: Olivier Guiter Signed-off-by: Samuel Ortiz --- drivers/nfc/pn533.c | 144 +++++++++++++++++++++++++++++++++++++++----- 1 file changed, 130 insertions(+), 14 deletions(-) diff --git a/drivers/nfc/pn533.c b/drivers/nfc/pn533.c index ae0fa9ee169d..f06ef7c49f84 100644 --- a/drivers/nfc/pn533.c +++ b/drivers/nfc/pn533.c @@ -363,12 +363,14 @@ struct pn533 { struct urb *in_urb; struct sk_buff_head resp_q; + struct sk_buff_head fragment_skb; struct workqueue_struct *wq; struct work_struct cmd_work; struct work_struct cmd_complete_work; struct work_struct poll_work; - struct work_struct mi_work; + struct work_struct mi_rx_work; + struct work_struct mi_tx_work; struct work_struct tg_work; struct work_struct rf_work; @@ -378,6 +380,7 @@ struct pn533 { struct mutex cmd_lock; /* protects cmd queue */ void *cmd_complete_mi_arg; + void *cmd_complete_dep_arg; struct pn533_poll_modulations *poll_mod_active[PN533_POLL_MOD_MAX + 1]; u8 poll_mod_count; @@ -2328,7 +2331,15 @@ static int pn533_data_exchange_complete(struct pn533 *dev, void *_arg, if (mi) { dev->cmd_complete_mi_arg = arg; - queue_work(dev->wq, &dev->mi_work); + queue_work(dev->wq, &dev->mi_rx_work); + return -EINPROGRESS; + } + + /* Prepare for the next round */ + if (skb_queue_len(&dev->fragment_skb) > 0) { + dev->cmd_complete_dep_arg = arg; + queue_work(dev->wq, &dev->mi_tx_work); + return -EINPROGRESS; } @@ -2349,6 +2360,50 @@ _error: return rc; } +/* Split the Tx skb into small chunks */ +static int pn533_fill_fragment_skbs(struct pn533 *dev, struct sk_buff *skb) +{ + struct sk_buff *frag; + int frag_size; + + do { + /* Remaining size */ + if (skb->len > PN533_CMD_DATAFRAME_MAXLEN) + frag_size = PN533_CMD_DATAFRAME_MAXLEN; + else + frag_size = skb->len; + + /* Allocate and reserve */ + frag = pn533_alloc_skb(dev, frag_size); + if (!frag) { + skb_queue_purge(&dev->fragment_skb); + break; + } + + /* Reserve the TG/MI byte */ + skb_reserve(frag, 1); + + /* MI + TG */ + if (frag_size == PN533_CMD_DATAFRAME_MAXLEN) + *skb_push(frag, sizeof(u8)) = (PN533_CMD_MI_MASK | 1); + else + *skb_push(frag, sizeof(u8)) = 1; /* TG */ + + memcpy(skb_put(frag, frag_size), skb->data, frag_size); + + /* Reduce the size of incoming buffer */ + skb_pull(skb, frag_size); + + /* Add this to skb_queue */ + skb_queue_tail(&dev->fragment_skb, frag); + + } while (skb->len > 0); + + dev_kfree_skb(skb); + + return skb_queue_len(&dev->fragment_skb); +} + static int pn533_transceive(struct nfc_dev *nfc_dev, struct nfc_target *target, struct sk_buff *skb, data_exchange_cb_t cb, void *cb_context) @@ -2359,15 +2414,6 @@ static int pn533_transceive(struct nfc_dev *nfc_dev, nfc_dev_dbg(&dev->interface->dev, "%s", __func__); - if (skb->len > PN533_CMD_DATAEXCH_DATA_MAXLEN) { - /* TODO: Implement support to multi-part data exchange */ - nfc_dev_err(&dev->interface->dev, - "Data length greater than the max allowed: %d", - PN533_CMD_DATAEXCH_DATA_MAXLEN); - rc = -ENOSYS; - goto error; - } - if (!dev->tgt_active_prot) { nfc_dev_err(&dev->interface->dev, "Can't exchange data if there is no active target"); @@ -2395,7 +2441,20 @@ static int pn533_transceive(struct nfc_dev *nfc_dev, break; } default: - *skb_push(skb, sizeof(u8)) = 1; /*TG*/ + /* jumbo frame ? */ + if (skb->len > PN533_CMD_DATAEXCH_DATA_MAXLEN) { + rc = pn533_fill_fragment_skbs(dev, skb); + if (rc <= 0) + goto error; + + skb = skb_dequeue(&dev->fragment_skb); + if (!skb) { + rc = -EIO; + goto error; + } + } else { + *skb_push(skb, sizeof(u8)) = 1; /* TG */ + } rc = pn533_send_data_async(dev, PN533_CMD_IN_DATA_EXCHANGE, skb, pn533_data_exchange_complete, @@ -2466,7 +2525,7 @@ static int pn533_tm_send(struct nfc_dev *nfc_dev, struct sk_buff *skb) static void pn533_wq_mi_recv(struct work_struct *work) { - struct pn533 *dev = container_of(work, struct pn533, mi_work); + struct pn533 *dev = container_of(work, struct pn533, mi_rx_work); struct sk_buff *skb; int rc; @@ -2514,6 +2573,61 @@ error: queue_work(dev->wq, &dev->cmd_work); } +static void pn533_wq_mi_send(struct work_struct *work) +{ + struct pn533 *dev = container_of(work, struct pn533, mi_tx_work); + struct sk_buff *skb; + int rc; + + nfc_dev_dbg(&dev->interface->dev, "%s", __func__); + + /* Grab the first skb in the queue */ + skb = skb_dequeue(&dev->fragment_skb); + + if (skb == NULL) { /* No more data */ + /* Reset the queue for future use */ + skb_queue_head_init(&dev->fragment_skb); + goto error; + } + + switch (dev->device_type) { + case PN533_DEVICE_PASORI: + if (dev->tgt_active_prot != NFC_PROTO_FELICA) { + rc = -EIO; + break; + } + + rc = pn533_send_cmd_direct_async(dev, PN533_CMD_IN_COMM_THRU, + skb, + pn533_data_exchange_complete, + dev->cmd_complete_dep_arg); + + break; + + default: + /* Still some fragments? */ + rc = pn533_send_cmd_direct_async(dev,PN533_CMD_IN_DATA_EXCHANGE, + skb, + pn533_data_exchange_complete, + dev->cmd_complete_dep_arg); + + break; + } + + if (rc == 0) /* success */ + return; + + nfc_dev_err(&dev->interface->dev, + "Error %d when trying to perform data_exchange", rc); + + dev_kfree_skb(skb); + kfree(dev->cmd_complete_dep_arg); + +error: + pn533_send_ack(dev, GFP_KERNEL); + queue_work(dev->wq, &dev->cmd_work); +} + static int pn533_set_configuration(struct pn533 *dev, u8 cfgitem, u8 *cfgdata, u8 cfgdata_len) { @@ -2816,7 +2930,8 @@ static int pn533_probe(struct usb_interface *interface, INIT_WORK(&dev->cmd_work, pn533_wq_cmd); INIT_WORK(&dev->cmd_complete_work, pn533_wq_cmd_complete); - INIT_WORK(&dev->mi_work, pn533_wq_mi_recv); + INIT_WORK(&dev->mi_rx_work, pn533_wq_mi_recv); + INIT_WORK(&dev->mi_tx_work, pn533_wq_mi_send); INIT_WORK(&dev->tg_work, pn533_wq_tg_get_data); INIT_WORK(&dev->poll_work, pn533_wq_poll); INIT_WORK(&dev->rf_work, pn533_wq_rf); @@ -2829,6 +2944,7 @@ static int pn533_probe(struct usb_interface *interface, dev->listen_timer.function = pn533_listen_mode_timer; skb_queue_head_init(&dev->resp_q); + skb_queue_head_init(&dev->fragment_skb); INIT_LIST_HEAD(&dev->cmd_queue); -- 2.20.1