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10#include <linux/device.h>
11#include <linux/kernel.h>
12#include <linux/module.h>
13#include <linux/nfc.h>
14#include <linux/netdevice.h>
15#include <linux/of.h>
16#include <linux/serdev.h>
17#include "pn533.h"
18
19#define PN532_UART_SKB_BUFF_LEN (PN533_CMD_DATAEXCH_DATA_MAXLEN * 2)
20
21enum send_wakeup {
22 PN532_SEND_NO_WAKEUP = 0,
23 PN532_SEND_WAKEUP,
24 PN532_SEND_LAST_WAKEUP,
25};
26
27
28struct pn532_uart_phy {
29 struct serdev_device *serdev;
30 struct sk_buff *recv_skb;
31 struct pn533 *priv;
32
33
34
35
36
37
38
39
40 enum send_wakeup send_wakeup;
41 struct timer_list cmd_timeout;
42 struct sk_buff *cur_out_buf;
43};
44
45static int pn532_uart_send_frame(struct pn533 *dev,
46 struct sk_buff *out)
47{
48
49 static const u8 wakeup[] = {
50 0x55, 0x55, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
51 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
52 struct pn532_uart_phy *pn532 = dev->phy;
53 int err;
54
55 print_hex_dump_debug("PN532_uart TX: ", DUMP_PREFIX_NONE, 16, 1,
56 out->data, out->len, false);
57
58 pn532->cur_out_buf = out;
59 if (pn532->send_wakeup) {
60 err = serdev_device_write(pn532->serdev,
61 wakeup, sizeof(wakeup),
62 MAX_SCHEDULE_TIMEOUT);
63 if (err < 0)
64 return err;
65 }
66
67 if (pn532->send_wakeup == PN532_SEND_LAST_WAKEUP)
68 pn532->send_wakeup = PN532_SEND_NO_WAKEUP;
69
70 err = serdev_device_write(pn532->serdev, out->data, out->len,
71 MAX_SCHEDULE_TIMEOUT);
72 if (err < 0)
73 return err;
74
75 mod_timer(&pn532->cmd_timeout, HZ / 40 + jiffies);
76 return 0;
77}
78
79static int pn532_uart_send_ack(struct pn533 *dev, gfp_t flags)
80{
81
82 static const u8 ack[PN533_STD_FRAME_ACK_SIZE] = {
83 0x00, 0x00, 0xff, 0x00, 0xff, 0x00};
84 struct pn532_uart_phy *pn532 = dev->phy;
85 int err;
86
87 err = serdev_device_write(pn532->serdev, ack, sizeof(ack),
88 MAX_SCHEDULE_TIMEOUT);
89 if (err < 0)
90 return err;
91
92 return 0;
93}
94
95static void pn532_uart_abort_cmd(struct pn533 *dev, gfp_t flags)
96{
97
98 pn532_uart_send_ack(dev, flags);
99
100 pn533_recv_frame(dev, NULL, -ENOENT);
101}
102
103static int pn532_dev_up(struct pn533 *dev)
104{
105 struct pn532_uart_phy *pn532 = dev->phy;
106 int ret = 0;
107
108 ret = serdev_device_open(pn532->serdev);
109 if (ret)
110 return ret;
111
112 pn532->send_wakeup = PN532_SEND_LAST_WAKEUP;
113 return ret;
114}
115
116static int pn532_dev_down(struct pn533 *dev)
117{
118 struct pn532_uart_phy *pn532 = dev->phy;
119
120 serdev_device_close(pn532->serdev);
121 pn532->send_wakeup = PN532_SEND_WAKEUP;
122
123 return 0;
124}
125
126static struct pn533_phy_ops uart_phy_ops = {
127 .send_frame = pn532_uart_send_frame,
128 .send_ack = pn532_uart_send_ack,
129 .abort_cmd = pn532_uart_abort_cmd,
130 .dev_up = pn532_dev_up,
131 .dev_down = pn532_dev_down,
132};
133
134static void pn532_cmd_timeout(struct timer_list *t)
135{
136 struct pn532_uart_phy *dev = from_timer(dev, t, cmd_timeout);
137
138 pn532_uart_send_frame(dev->priv, dev->cur_out_buf);
139}
140
141
142
143
144
145
146
147
148static int pn532_uart_rx_is_frame(struct sk_buff *skb)
149{
150 struct pn533_std_frame *std;
151 struct pn533_ext_frame *ext;
152 u16 frame_len;
153 int i;
154
155 for (i = 0; i + PN533_STD_FRAME_ACK_SIZE <= skb->len; i++) {
156 std = (struct pn533_std_frame *)&skb->data[i];
157
158 if (std->start_frame != cpu_to_be16(PN533_STD_FRAME_SOF))
159 continue;
160
161
162 switch (std->datalen) {
163 case PN533_FRAME_DATALEN_ACK:
164 if (std->datalen_checksum == 0xff) {
165 skb_pull(skb, i);
166 return 1;
167 }
168
169 break;
170 case PN533_FRAME_DATALEN_ERROR:
171 if ((std->datalen_checksum == 0xff) &&
172 (skb->len >=
173 PN533_STD_ERROR_FRAME_SIZE)) {
174 skb_pull(skb, i);
175 return 1;
176 }
177
178 break;
179 case PN533_FRAME_DATALEN_EXTENDED:
180 ext = (struct pn533_ext_frame *)&skb->data[i];
181 frame_len = be16_to_cpu(ext->datalen);
182 if (skb->len >= frame_len +
183 sizeof(struct pn533_ext_frame) +
184 2 ) {
185 skb_pull(skb, i);
186 return 1;
187 }
188
189 break;
190 default:
191 frame_len = std->datalen;
192 if (skb->len >= frame_len +
193 sizeof(struct pn533_std_frame) +
194 2 ) {
195 skb_pull(skb, i);
196 return 1;
197 }
198
199 break;
200 }
201 }
202
203 return 0;
204}
205
206static int pn532_receive_buf(struct serdev_device *serdev,
207 const unsigned char *data, size_t count)
208{
209 struct pn532_uart_phy *dev = serdev_device_get_drvdata(serdev);
210 size_t i;
211
212 del_timer(&dev->cmd_timeout);
213 for (i = 0; i < count; i++) {
214 skb_put_u8(dev->recv_skb, *data++);
215 if (!pn532_uart_rx_is_frame(dev->recv_skb))
216 continue;
217
218 pn533_recv_frame(dev->priv, dev->recv_skb, 0);
219 dev->recv_skb = alloc_skb(PN532_UART_SKB_BUFF_LEN, GFP_KERNEL);
220 if (!dev->recv_skb)
221 return 0;
222 }
223
224 return i;
225}
226
227static struct serdev_device_ops pn532_serdev_ops = {
228 .receive_buf = pn532_receive_buf,
229 .write_wakeup = serdev_device_write_wakeup,
230};
231
232static const struct of_device_id pn532_uart_of_match[] = {
233 { .compatible = "nxp,pn532", },
234 {},
235};
236MODULE_DEVICE_TABLE(of, pn532_uart_of_match);
237
238static int pn532_uart_probe(struct serdev_device *serdev)
239{
240 struct pn532_uart_phy *pn532;
241 struct pn533 *priv;
242 int err;
243
244 err = -ENOMEM;
245 pn532 = kzalloc(sizeof(*pn532), GFP_KERNEL);
246 if (!pn532)
247 goto err_exit;
248
249 pn532->recv_skb = alloc_skb(PN532_UART_SKB_BUFF_LEN, GFP_KERNEL);
250 if (!pn532->recv_skb)
251 goto err_free;
252
253 pn532->serdev = serdev;
254 serdev_device_set_drvdata(serdev, pn532);
255 serdev_device_set_client_ops(serdev, &pn532_serdev_ops);
256 err = serdev_device_open(serdev);
257 if (err) {
258 dev_err(&serdev->dev, "Unable to open device\n");
259 goto err_skb;
260 }
261
262 err = serdev_device_set_baudrate(serdev, 115200);
263 if (err != 115200) {
264 err = -EINVAL;
265 goto err_serdev;
266 }
267
268 serdev_device_set_flow_control(serdev, false);
269 pn532->send_wakeup = PN532_SEND_WAKEUP;
270 timer_setup(&pn532->cmd_timeout, pn532_cmd_timeout, 0);
271 priv = pn53x_common_init(PN533_DEVICE_PN532_AUTOPOLL,
272 PN533_PROTO_REQ_ACK_RESP,
273 pn532, &uart_phy_ops, NULL,
274 &pn532->serdev->dev);
275 if (IS_ERR(priv)) {
276 err = PTR_ERR(priv);
277 goto err_serdev;
278 }
279
280 pn532->priv = priv;
281 err = pn533_finalize_setup(pn532->priv);
282 if (err)
283 goto err_clean;
284
285 serdev_device_close(serdev);
286 err = pn53x_register_nfc(priv, PN533_NO_TYPE_B_PROTOCOLS, &serdev->dev);
287 if (err) {
288 pn53x_common_clean(pn532->priv);
289 goto err_skb;
290 }
291
292 return err;
293
294err_clean:
295 pn53x_common_clean(pn532->priv);
296err_serdev:
297 serdev_device_close(serdev);
298err_skb:
299 kfree_skb(pn532->recv_skb);
300err_free:
301 kfree(pn532);
302err_exit:
303 return err;
304}
305
306static void pn532_uart_remove(struct serdev_device *serdev)
307{
308 struct pn532_uart_phy *pn532 = serdev_device_get_drvdata(serdev);
309
310 pn53x_unregister_nfc(pn532->priv);
311 serdev_device_close(serdev);
312 pn53x_common_clean(pn532->priv);
313 kfree_skb(pn532->recv_skb);
314 kfree(pn532);
315}
316
317static struct serdev_device_driver pn532_uart_driver = {
318 .probe = pn532_uart_probe,
319 .remove = pn532_uart_remove,
320 .driver = {
321 .name = "pn532_uart",
322 .of_match_table = pn532_uart_of_match,
323 },
324};
325
326module_serdev_device_driver(pn532_uart_driver);
327
328MODULE_AUTHOR("Lars Pöschel <poeschel@lemonage.de>");
329MODULE_DESCRIPTION("PN532 UART driver");
330MODULE_LICENSE("GPL");
331
