/*
* 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 <linux/module.h>
#include "digital.h"
#define DIGITAL_PROTO_NFCA_RF_TECH \
(NFC_PROTO_JEWEL_MASK | NFC_PROTO_MIFARE_MASK | \
NFC_PROTO_NFC_DEP_MASK | NFC_PROTO_ISO14443_MASK)
#define DIGITAL_PROTO_NFCB_RF_TECH NFC_PROTO_ISO14443_B_MASK
#define DIGITAL_PROTO_NFCF_RF_TECH \
(NFC_PROTO_FELICA_MASK | NFC_PROTO_NFC_DEP_MASK)
#define DIGITAL_PROTO_ISO15693_RF_TECH NFC_PROTO_ISO15693_MASK
/* Delay between each poll frame (ms) */
#define DIGITAL_POLL_INTERVAL 10
struct digital_cmd {
struct list_head queue;
u8 type;
u8 pending;
u16 timeout;
struct sk_buff *req;
struct sk_buff *resp;
struct digital_tg_mdaa_params *mdaa_params;
nfc_digital_cmd_complete_t cmd_cb;
void *cb_context;
};
struct sk_buff *digital_skb_alloc(struct nfc_digital_dev *ddev,
unsigned int len)
{
struct sk_buff *skb;
skb = alloc_skb(len + ddev->tx_headroom + ddev->tx_tailroom,
GFP_KERNEL);
if (skb)
skb_reserve(skb, ddev->tx_headroom);
return skb;
}
void digital_skb_add_crc(struct sk_buff *skb, crc_func_t crc_func, u16 init,
u8 bitwise_inv, u8 msb_first)
{
u16 crc;
crc = crc_func(init, skb->data, skb->len);
if (bitwise_inv)
crc = ~crc;
if (msb_first)
crc = __fswab16(crc);
skb_put_u8(skb, crc & 0xFF);
skb_put_u8(skb, (crc >> 8) & 0xFF);
}
int digital_skb_check_crc(struct sk_buff *skb, crc_func_t crc_func,
u16 crc_init, u8 bitwise_inv, u8 msb_first)
{
int rc;
u16 crc;
if (skb->len <= 2)
return -EIO;
crc = crc_func(crc_init, skb->data, skb->len - 2);
if (bitwise_inv)
crc = ~crc;
if (msb_first)
crc = __swab16(crc);
rc = (skb->data[skb->len - 2] - (crc & 0xFF)) +
(skb->data[skb->len - 1] - ((crc >> 8) & 0xFF));
if (rc)
return -EIO;
skb_trim(skb, skb->len - 2);
return 0;
}
static inline void digital_switch_rf(struct nfc_digital_dev *ddev, bool on)
{
ddev->ops->switch_rf(ddev, on);
}
static inline void digital_abort_cmd(struct nfc_digital_dev *ddev)
{
ddev->ops->abort_cmd(ddev);
}
static void digital_wq_cmd_complete(struct work_struct *work)
{
struct digital_cmd *cmd;
struct nfc_digital_dev *ddev = container_of(work,
struct nfc_digital_dev,
cmd_complete_work);
mutex_lock(&ddev->cmd_lock);
cmd = list_first_entry_or_null(&ddev->cmd_queue, struct digital_cmd,
queue);
if (!cmd) {
mutex_unlock(&ddev->cmd_lock);
return;
}
list_del(&cmd->queue);
mutex_unlock(&ddev->cmd_lock);
if (!IS_ERR(cmd->resp))
print_hex_dump_debug("DIGITAL RX: ", DUMP_PREFIX_NONE, 16, 1,
cmd->resp->data, cmd->resp->len, false);
cmd->cmd_cb(ddev, cmd->cb_context, cmd->resp);
kfree(cmd->mdaa_params);
kfree(cmd);
schedule_work(&ddev->cmd_work);
}
static void digital_send_cmd_complete(struct nfc_digital_dev *ddev,
void *arg, struct sk_buff *resp)
{
struct digital_cmd *cmd = arg;
cmd->resp = resp;
schedule_work(&ddev->cmd_complete_work);
}
static void digital_wq_cmd(struct work_struct *work)
{
int rc;
struct digital_cmd *cmd;
struct digital_tg_mdaa_params *params;
struct nfc_digital_dev *ddev = container_of(work,
struct nfc_digital_dev,
cmd_work);
mutex_lock(&ddev->cmd_lock);
cmd = list_first_entry_or_null(&ddev->cmd_queue, struct digital_cmd,
queue);
if (!cmd || cmd->pending) {
mutex_unlock(&ddev->cmd_lock);
return;
}
cmd->pending = 1;
mutex_unlock(&ddev->cmd_lock);
if (cmd->req)
print_hex_dump_debug("DIGITAL TX: ", DUMP_PREFIX_NONE, 16, 1,
cmd->req->data, cmd->req->len, false);
switch (cmd->type) {
case DIGITAL_CMD_IN_SEND:
rc = ddev->ops->in_send_cmd(ddev, cmd->req, cmd->timeout,
digital_send_cmd_complete, cmd);