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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
| commit | 4352b8aee98005853aa63f57d6377282de17a33f (patch) | |
| tree | 27614d7a9ef05c32d089004e104364ce42324837 /net/nfc/nci/data.c | |
| download | linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip | |
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni:
"A new driver this cycle, for the AMD AXI I3C controller.
There are also new features such as IBI wakeup support, SETAASA device
discovery and ACPI support for the the DAA methods, meaning we can now
communicate with the SPD devices on DDR5 modules.
New driver:
- AMD AXI I3C master controller
Subsystem:
- I3C Common Command Code (CCC) handling improvements, especially
around GET CCCs
- SETAASA device discovery support
- ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
well as I2C devices on I3C bus
- IBI-based wakeup support
Drivers:
- dw: SETAASA support
- mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
controller support, PIO queue management support for HCI v1.2
- renesas: improve suspend to RAM support, add runtime PM support"
* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
i3c: dw: reduce do_daa time if there's no client
i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
i3c: dw: rename "pclk" to "apb" to match dt-binding
i3c: dw: make struct dw_i3c_cmd smaller
i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
i3c: renesas: Don't register devices when ENTDAA times out
i3c: master: dw-i3c-master: fix OD timing for first broadcast
i3c: mipi-i3c-hci: Advertise IBI wakeup capability
i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
i3c: master: Reject IBI requests from non-IBI-capable devices
i3c: master: Add helper to query bus wakeup requirements
i3c: master: Report wakeup events for IBIs
i3c: master: Support IBI-based wakeup capability
i3c: master: Fix potential UAF in i3c_device_match()
i3c: master: Fix potential UAF in i3c_device_uevent()
i3c: Make dev->desc locking assumptions explicit
i3c: master: Fix use-after-free of master->this
...
Diffstat (limited to 'net/nfc/nci/data.c')
| -rw-r--r-- | net/nfc/nci/data.c | 305 |
1 files changed, 305 insertions, 0 deletions
diff --git a/net/nfc/nci/data.c b/net/nfc/nci/data.c new file mode 100644 index 000000000..4253edea5 --- /dev/null +++ b/net/nfc/nci/data.c @@ -0,0 +1,305 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * The NFC Controller Interface is the communication protocol between an + * NFC Controller (NFCC) and a Device Host (DH). + * + * Copyright (C) 2011 Texas Instruments, Inc. + * Copyright (C) 2014 Marvell International Ltd. + * + * Written by Ilan Elias <ilane@ti.com> + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__ + +#include <linux/types.h> +#include <linux/interrupt.h> +#include <linux/wait.h> +#include <linux/bitops.h> +#include <linux/skbuff.h> + +#include "../nfc.h" +#include <net/nfc/nci.h> +#include <net/nfc/nci_core.h> +#include <linux/nfc.h> + +/* Complete data exchange transaction and forward skb to nfc core */ +void nci_data_exchange_complete(struct nci_dev *ndev, struct sk_buff *skb, + __u8 conn_id, int err) +{ + const struct nci_conn_info *conn_info; + data_exchange_cb_t cb; + void *cb_context; + + conn_info = nci_get_conn_info_by_conn_id(ndev, conn_id); + if (!conn_info) { + kfree_skb(skb); + clear_bit(NCI_DATA_EXCHANGE, &ndev->flags); + return; + } + + cb = conn_info->data_exchange_cb; + cb_context = conn_info->data_exchange_cb_context; + + pr_debug("len %d, err %d\n", skb ? skb->len : 0, err); + + /* data exchange is complete, stop the data timer */ + timer_delete_sync(&ndev->data_timer); + clear_bit(NCI_DATA_EXCHANGE_TO, &ndev->flags); + + /* Claim completion atomically -- both close and rx_work may race here */ + if (!test_and_clear_bit(NCI_DATA_EXCHANGE, &ndev->flags)) { + kfree_skb(skb); + return; + } + + if (cb) { + /* forward skb to nfc core */ + cb(cb_context, skb, err); + } else if (skb) { + pr_err("no rx callback, dropping rx data...\n"); + + /* no waiting callback, free skb */ + kfree_skb(skb); + } +} + +/* ----------------- NCI TX Data ----------------- */ + +static inline void nci_push_data_hdr(struct nci_dev *ndev, + __u8 conn_id, + struct sk_buff *skb, + __u8 pbf) +{ + struct nci_data_hdr *hdr; + int plen = skb->len; + + hdr = skb_push(skb, NCI_DATA_HDR_SIZE); + hdr->conn_id = conn_id; + hdr->rfu = 0; + hdr->plen = plen; + + nci_mt_set((__u8 *)hdr, NCI_MT_DATA_PKT); + nci_pbf_set((__u8 *)hdr, pbf); +} + +int nci_conn_max_data_pkt_payload_size(struct nci_dev *ndev, __u8 conn_id) +{ + const struct nci_conn_info *conn_info; + + conn_info = nci_get_conn_info_by_conn_id(ndev, conn_id); + if (!conn_info) + return -EPROTO; + + return conn_info->max_pkt_payload_len; +} +EXPORT_SYMBOL(nci_conn_max_data_pkt_payload_size); + +static int nci_queue_tx_data_frags(struct nci_dev *ndev, + __u8 conn_id, + struct sk_buff *skb) { + const struct nci_conn_info *conn_info; + int total_len = skb->len; + const unsigned char *data = skb->data; + unsigned long flags; + struct sk_buff_head frags_q; + struct sk_buff *skb_frag; + int frag_len; + int rc = 0; + + pr_debug("conn_id 0x%x, total_len %d\n", conn_id, total_len); + + conn_info = nci_get_conn_info_by_conn_id(ndev, conn_id); + if (!conn_info) { + rc = -EPROTO; + goto exit; + } + + __skb_queue_head_init(&frags_q); + + while (total_len) { + frag_len = + min_t(int, total_len, conn_info->max_pkt_payload_len); + + skb_frag = nci_skb_alloc(ndev, + (NCI_DATA_HDR_SIZE + frag_len), + GFP_ATOMIC); + if (skb_frag == NULL) { + rc = -ENOMEM; + goto free_exit; + } + skb_reserve(skb_frag, NCI_DATA_HDR_SIZE); + + /* first, copy the data */ + skb_put_data(skb_frag, data, frag_len); + + /* second, set the header */ + nci_push_data_hdr(ndev, conn_id, skb_frag, + ((total_len == frag_len) ? + (NCI_PBF_LAST) : (NCI_PBF_CONT))); + + __skb_queue_tail(&frags_q, skb_frag); + + data += frag_len; + total_len -= frag_len; + + pr_debug("frag_len %d, remaining total_len %d\n", + frag_len, total_len); + } + + /* queue all fragments atomically */ + spin_lock_irqsave(&ndev->tx_q.lock, flags); + + while ((skb_frag = __skb_dequeue(&frags_q)) != NULL) + __skb_queue_tail(&ndev->tx_q, skb_frag); + + spin_unlock_irqrestore(&ndev->tx_q.lock, flags); + + /* free the original skb */ + kfree_skb(skb); + + goto exit; + +free_exit: + while ((skb_frag = __skb_dequeue(&frags_q)) != NULL) + kfree_skb(skb_frag); + +exit: + return rc; +} + +/* Send NCI data */ +int nci_send_data(struct nci_dev *ndev, __u8 conn_id, struct sk_buff *skb) +{ + const struct nci_conn_info *conn_info; + int rc = 0; + + pr_debug("conn_id 0x%x, plen %d\n", conn_id, skb->len); + + conn_info = nci_get_conn_info_by_conn_id(ndev, conn_id); + if (!conn_info) { + rc = -EPROTO; + goto free_exit; + } + + /* check if the packet need to be fragmented */ + if (skb->len <= conn_info->max_pkt_payload_len) { + /* no need to fragment packet */ + nci_push_data_hdr(ndev, conn_id, skb, NCI_PBF_LAST); + + skb_queue_tail(&ndev->tx_q, skb); + } else { + /* fragment packet and queue the fragments */ + rc = nci_queue_tx_data_frags(ndev, conn_id, skb); + if (rc) { + pr_err("failed to fragment tx data packet\n"); + goto free_exit; + } + } + + ndev->cur_conn_id = conn_id; + queue_work(ndev->tx_wq, &ndev->tx_work); + + goto exit; + +free_exit: + kfree_skb(skb); + +exit: + return rc; +} +EXPORT_SYMBOL(nci_send_data); + +/* ----------------- NCI RX Data ----------------- */ + +static void nci_add_rx_data_frag(struct nci_dev *ndev, + struct sk_buff *skb, + __u8 pbf, __u8 conn_id, __u8 status) +{ + int reassembly_len; + int err = 0; + + if (status) { + err = status; + goto exit; + } + + if (ndev->rx_data_reassembly) { + reassembly_len = ndev->rx_data_reassembly->len; + + /* first, make enough room for the already accumulated data */ + if (skb_cow_head(skb, reassembly_len)) { + pr_err("error adding room for accumulated rx data\n"); + + kfree_skb(skb); + skb = NULL; + + kfree_skb(ndev->rx_data_reassembly); + ndev->rx_data_reassembly = NULL; + + err = -ENOMEM; + goto exit; + } + + /* second, combine the two fragments */ + memcpy(skb_push(skb, reassembly_len), + ndev->rx_data_reassembly->data, + reassembly_len); + + /* third, free old reassembly */ + kfree_skb(ndev->rx_data_reassembly); + ndev->rx_data_reassembly = NULL; + } + + if (pbf == NCI_PBF_CONT) { + /* need to wait for next fragment, store skb and exit */ + ndev->rx_data_reassembly = skb; + return; + } + +exit: + if (ndev->nfc_dev->rf_mode == NFC_RF_TARGET) { + /* Data received in Target mode, forward to nfc core */ + err = nfc_tm_data_received(ndev->nfc_dev, skb); + if (err) + pr_err("unable to handle received data\n"); + } else { + nci_data_exchange_complete(ndev, skb, conn_id, err); + } +} + +/* Rx Data packet */ +void nci_rx_data_packet(struct nci_dev *ndev, struct sk_buff *skb) +{ + __u8 pbf = nci_pbf(skb->data); + __u8 status = 0; + __u8 conn_id = nci_conn_id(skb->data); + const struct nci_conn_info *conn_info; + + pr_debug("len %d\n", skb->len); + + pr_debug("NCI RX: MT=data, PBF=%d, conn_id=%d, plen=%d\n", + nci_pbf(skb->data), + nci_conn_id(skb->data), + nci_plen(skb->data)); + + conn_info = nci_get_conn_info_by_conn_id(ndev, nci_conn_id(skb->data)); + if (!conn_info) { + kfree_skb(skb); + return; + } + + /* strip the nci data header */ + skb_pull(skb, NCI_DATA_HDR_SIZE); + + if (ndev->target_active_prot == NFC_PROTO_MIFARE || + ndev->target_active_prot == NFC_PROTO_JEWEL || + ndev->target_active_prot == NFC_PROTO_FELICA || + ndev->target_active_prot == NFC_PROTO_ISO15693) { + /* frame I/F => remove the status byte */ + pr_debug("frame I/F => remove the status byte\n"); + status = skb->data[skb->len - 1]; + skb_trim(skb, (skb->len - 1)); + } + + nci_add_rx_data_frag(ndev, skb, pbf, conn_id, nci_to_errno(status)); +} |
