mirror of https://gitee.com/openkylin/linux.git
331 lines
7.9 KiB
C
331 lines
7.9 KiB
C
// SPDX-License-Identifier: GPL-2.0+
|
|
/*
|
|
* Driver for NXP PN532 NFC Chip - UART transport layer
|
|
*
|
|
* Copyright (C) 2018 Lemonage Software GmbH
|
|
* Author: Lars Pöschel <poeschel@lemonage.de>
|
|
* All rights reserved.
|
|
*/
|
|
|
|
#include <linux/device.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/nfc.h>
|
|
#include <linux/netdevice.h>
|
|
#include <linux/of.h>
|
|
#include <linux/serdev.h>
|
|
#include "pn533.h"
|
|
|
|
#define PN532_UART_SKB_BUFF_LEN (PN533_CMD_DATAEXCH_DATA_MAXLEN * 2)
|
|
|
|
enum send_wakeup {
|
|
PN532_SEND_NO_WAKEUP = 0,
|
|
PN532_SEND_WAKEUP,
|
|
PN532_SEND_LAST_WAKEUP,
|
|
};
|
|
|
|
|
|
struct pn532_uart_phy {
|
|
struct serdev_device *serdev;
|
|
struct sk_buff *recv_skb;
|
|
struct pn533 *priv;
|
|
/*
|
|
* send_wakeup variable is used to control if we need to send a wakeup
|
|
* request to the pn532 chip prior to our actual command. There is a
|
|
* little propability of a race condition. We decided to not mutex the
|
|
* variable as the worst that could happen is, that we send a wakeup
|
|
* to the chip that is already awake. This does not hurt. It is a
|
|
* no-op to the chip.
|
|
*/
|
|
enum send_wakeup send_wakeup;
|
|
struct timer_list cmd_timeout;
|
|
struct sk_buff *cur_out_buf;
|
|
};
|
|
|
|
static int pn532_uart_send_frame(struct pn533 *dev,
|
|
struct sk_buff *out)
|
|
{
|
|
/* wakeup sequence and dummy bytes for waiting time */
|
|
static const u8 wakeup[] = {
|
|
0x55, 0x55, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
|
|
0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
|
|
struct pn532_uart_phy *pn532 = dev->phy;
|
|
int err;
|
|
|
|
print_hex_dump_debug("PN532_uart TX: ", DUMP_PREFIX_NONE, 16, 1,
|
|
out->data, out->len, false);
|
|
|
|
pn532->cur_out_buf = out;
|
|
if (pn532->send_wakeup) {
|
|
err = serdev_device_write(pn532->serdev,
|
|
wakeup, sizeof(wakeup),
|
|
MAX_SCHEDULE_TIMEOUT);
|
|
if (err < 0)
|
|
return err;
|
|
}
|
|
|
|
if (pn532->send_wakeup == PN532_SEND_LAST_WAKEUP)
|
|
pn532->send_wakeup = PN532_SEND_NO_WAKEUP;
|
|
|
|
err = serdev_device_write(pn532->serdev, out->data, out->len,
|
|
MAX_SCHEDULE_TIMEOUT);
|
|
if (err < 0)
|
|
return err;
|
|
|
|
mod_timer(&pn532->cmd_timeout, HZ / 40 + jiffies);
|
|
return 0;
|
|
}
|
|
|
|
static int pn532_uart_send_ack(struct pn533 *dev, gfp_t flags)
|
|
{
|
|
/* spec 7.1.1.3: Preamble, SoPC (2), ACK Code (2), Postamble */
|
|
static const u8 ack[PN533_STD_FRAME_ACK_SIZE] = {
|
|
0x00, 0x00, 0xff, 0x00, 0xff, 0x00};
|
|
struct pn532_uart_phy *pn532 = dev->phy;
|
|
int err;
|
|
|
|
err = serdev_device_write(pn532->serdev, ack, sizeof(ack),
|
|
MAX_SCHEDULE_TIMEOUT);
|
|
if (err < 0)
|
|
return err;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void pn532_uart_abort_cmd(struct pn533 *dev, gfp_t flags)
|
|
{
|
|
/* An ack will cancel the last issued command */
|
|
pn532_uart_send_ack(dev, flags);
|
|
/* schedule cmd_complete_work to finish current command execution */
|
|
pn533_recv_frame(dev, NULL, -ENOENT);
|
|
}
|
|
|
|
static int pn532_dev_up(struct pn533 *dev)
|
|
{
|
|
struct pn532_uart_phy *pn532 = dev->phy;
|
|
int ret = 0;
|
|
|
|
ret = serdev_device_open(pn532->serdev);
|
|
if (ret)
|
|
return ret;
|
|
|
|
pn532->send_wakeup = PN532_SEND_LAST_WAKEUP;
|
|
return ret;
|
|
}
|
|
|
|
static int pn532_dev_down(struct pn533 *dev)
|
|
{
|
|
struct pn532_uart_phy *pn532 = dev->phy;
|
|
|
|
serdev_device_close(pn532->serdev);
|
|
pn532->send_wakeup = PN532_SEND_WAKEUP;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct pn533_phy_ops uart_phy_ops = {
|
|
.send_frame = pn532_uart_send_frame,
|
|
.send_ack = pn532_uart_send_ack,
|
|
.abort_cmd = pn532_uart_abort_cmd,
|
|
.dev_up = pn532_dev_up,
|
|
.dev_down = pn532_dev_down,
|
|
};
|
|
|
|
static void pn532_cmd_timeout(struct timer_list *t)
|
|
{
|
|
struct pn532_uart_phy *dev = from_timer(dev, t, cmd_timeout);
|
|
|
|
pn532_uart_send_frame(dev->priv, dev->cur_out_buf);
|
|
}
|
|
|
|
/*
|
|
* scans the buffer if it contains a pn532 frame. It is not checked if the
|
|
* frame is really valid. This is later done with pn533_rx_frame_is_valid.
|
|
* This is useful for malformed or errornous transmitted frames. Adjusts the
|
|
* bufferposition where the frame starts, since pn533_recv_frame expects a
|
|
* well formed frame.
|
|
*/
|
|
static int pn532_uart_rx_is_frame(struct sk_buff *skb)
|
|
{
|
|
struct pn533_std_frame *std;
|
|
struct pn533_ext_frame *ext;
|
|
u16 frame_len;
|
|
int i;
|
|
|
|
for (i = 0; i + PN533_STD_FRAME_ACK_SIZE <= skb->len; i++) {
|
|
std = (struct pn533_std_frame *)&skb->data[i];
|
|
/* search start code */
|
|
if (std->start_frame != cpu_to_be16(PN533_STD_FRAME_SOF))
|
|
continue;
|
|
|
|
/* frame type */
|
|
switch (std->datalen) {
|
|
case PN533_FRAME_DATALEN_ACK:
|
|
if (std->datalen_checksum == 0xff) {
|
|
skb_pull(skb, i);
|
|
return 1;
|
|
}
|
|
|
|
break;
|
|
case PN533_FRAME_DATALEN_ERROR:
|
|
if ((std->datalen_checksum == 0xff) &&
|
|
(skb->len >=
|
|
PN533_STD_ERROR_FRAME_SIZE)) {
|
|
skb_pull(skb, i);
|
|
return 1;
|
|
}
|
|
|
|
break;
|
|
case PN533_FRAME_DATALEN_EXTENDED:
|
|
ext = (struct pn533_ext_frame *)&skb->data[i];
|
|
frame_len = be16_to_cpu(ext->datalen);
|
|
if (skb->len >= frame_len +
|
|
sizeof(struct pn533_ext_frame) +
|
|
2 /* CKS + Postamble */) {
|
|
skb_pull(skb, i);
|
|
return 1;
|
|
}
|
|
|
|
break;
|
|
default: /* normal information frame */
|
|
frame_len = std->datalen;
|
|
if (skb->len >= frame_len +
|
|
sizeof(struct pn533_std_frame) +
|
|
2 /* CKS + Postamble */) {
|
|
skb_pull(skb, i);
|
|
return 1;
|
|
}
|
|
|
|
break;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int pn532_receive_buf(struct serdev_device *serdev,
|
|
const unsigned char *data, size_t count)
|
|
{
|
|
struct pn532_uart_phy *dev = serdev_device_get_drvdata(serdev);
|
|
size_t i;
|
|
|
|
del_timer(&dev->cmd_timeout);
|
|
for (i = 0; i < count; i++) {
|
|
skb_put_u8(dev->recv_skb, *data++);
|
|
if (!pn532_uart_rx_is_frame(dev->recv_skb))
|
|
continue;
|
|
|
|
pn533_recv_frame(dev->priv, dev->recv_skb, 0);
|
|
dev->recv_skb = alloc_skb(PN532_UART_SKB_BUFF_LEN, GFP_KERNEL);
|
|
if (!dev->recv_skb)
|
|
return 0;
|
|
}
|
|
|
|
return i;
|
|
}
|
|
|
|
static struct serdev_device_ops pn532_serdev_ops = {
|
|
.receive_buf = pn532_receive_buf,
|
|
.write_wakeup = serdev_device_write_wakeup,
|
|
};
|
|
|
|
static const struct of_device_id pn532_uart_of_match[] = {
|
|
{ .compatible = "nxp,pn532", },
|
|
{},
|
|
};
|
|
MODULE_DEVICE_TABLE(of, pn532_uart_of_match);
|
|
|
|
static int pn532_uart_probe(struct serdev_device *serdev)
|
|
{
|
|
struct pn532_uart_phy *pn532;
|
|
struct pn533 *priv;
|
|
int err;
|
|
|
|
err = -ENOMEM;
|
|
pn532 = kzalloc(sizeof(*pn532), GFP_KERNEL);
|
|
if (!pn532)
|
|
goto err_exit;
|
|
|
|
pn532->recv_skb = alloc_skb(PN532_UART_SKB_BUFF_LEN, GFP_KERNEL);
|
|
if (!pn532->recv_skb)
|
|
goto err_free;
|
|
|
|
pn532->serdev = serdev;
|
|
serdev_device_set_drvdata(serdev, pn532);
|
|
serdev_device_set_client_ops(serdev, &pn532_serdev_ops);
|
|
err = serdev_device_open(serdev);
|
|
if (err) {
|
|
dev_err(&serdev->dev, "Unable to open device\n");
|
|
goto err_skb;
|
|
}
|
|
|
|
err = serdev_device_set_baudrate(serdev, 115200);
|
|
if (err != 115200) {
|
|
err = -EINVAL;
|
|
goto err_serdev;
|
|
}
|
|
|
|
serdev_device_set_flow_control(serdev, false);
|
|
pn532->send_wakeup = PN532_SEND_WAKEUP;
|
|
timer_setup(&pn532->cmd_timeout, pn532_cmd_timeout, 0);
|
|
priv = pn53x_common_init(PN533_DEVICE_PN532_AUTOPOLL,
|
|
PN533_PROTO_REQ_ACK_RESP,
|
|
pn532, &uart_phy_ops, NULL,
|
|
&pn532->serdev->dev);
|
|
if (IS_ERR(priv)) {
|
|
err = PTR_ERR(priv);
|
|
goto err_serdev;
|
|
}
|
|
|
|
pn532->priv = priv;
|
|
err = pn533_finalize_setup(pn532->priv);
|
|
if (err)
|
|
goto err_clean;
|
|
|
|
serdev_device_close(serdev);
|
|
err = pn53x_register_nfc(priv, PN533_NO_TYPE_B_PROTOCOLS, &serdev->dev);
|
|
if (err) {
|
|
pn53x_common_clean(pn532->priv);
|
|
goto err_skb;
|
|
}
|
|
|
|
return err;
|
|
|
|
err_clean:
|
|
pn53x_common_clean(pn532->priv);
|
|
err_serdev:
|
|
serdev_device_close(serdev);
|
|
err_skb:
|
|
kfree_skb(pn532->recv_skb);
|
|
err_free:
|
|
kfree(pn532);
|
|
err_exit:
|
|
return err;
|
|
}
|
|
|
|
static void pn532_uart_remove(struct serdev_device *serdev)
|
|
{
|
|
struct pn532_uart_phy *pn532 = serdev_device_get_drvdata(serdev);
|
|
|
|
pn53x_unregister_nfc(pn532->priv);
|
|
serdev_device_close(serdev);
|
|
pn53x_common_clean(pn532->priv);
|
|
kfree_skb(pn532->recv_skb);
|
|
kfree(pn532);
|
|
}
|
|
|
|
static struct serdev_device_driver pn532_uart_driver = {
|
|
.probe = pn532_uart_probe,
|
|
.remove = pn532_uart_remove,
|
|
.driver = {
|
|
.name = "pn532_uart",
|
|
.of_match_table = of_match_ptr(pn532_uart_of_match),
|
|
},
|
|
};
|
|
|
|
module_serdev_device_driver(pn532_uart_driver);
|
|
|
|
MODULE_AUTHOR("Lars Pöschel <poeschel@lemonage.de>");
|
|
MODULE_DESCRIPTION("PN532 UART driver");
|
|
MODULE_LICENSE("GPL");
|