1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Driver for NXP PN533 NFC Chip - I2C transport layer |
4 | * |
5 | * Copyright (C) 2011 Instituto Nokia de Tecnologia |
6 | * Copyright (C) 2012-2013 Tieto Poland |
7 | * Copyright (C) 2016 HALE electronic |
8 | */ |
9 | |
10 | #include <linux/device.h> |
11 | #include <linux/kernel.h> |
12 | #include <linux/module.h> |
13 | #include <linux/slab.h> |
14 | #include <linux/i2c.h> |
15 | #include <linux/nfc.h> |
16 | #include <linux/netdevice.h> |
17 | #include <linux/interrupt.h> |
18 | #include <net/nfc/nfc.h> |
19 | #include "pn533.h" |
20 | |
21 | #define VERSION "0.1" |
22 | |
23 | #define PN533_I2C_DRIVER_NAME "pn533_i2c" |
24 | |
25 | struct pn533_i2c_phy { |
26 | struct i2c_client *i2c_dev; |
27 | struct pn533 *priv; |
28 | |
29 | bool aborted; |
30 | |
31 | int hard_fault; /* |
32 | * < 0 if hardware error occurred (e.g. i2c err) |
33 | * and prevents normal operation. |
34 | */ |
35 | }; |
36 | |
37 | static int pn533_i2c_send_ack(struct pn533 *dev, gfp_t flags) |
38 | { |
39 | struct pn533_i2c_phy *phy = dev->phy; |
40 | struct i2c_client *client = phy->i2c_dev; |
41 | static const u8 ack[6] = {0x00, 0x00, 0xff, 0x00, 0xff, 0x00}; |
42 | /* spec 6.2.1.3: Preamble, SoPC (2), ACK Code (2), Postamble */ |
43 | |
44 | return i2c_master_send(client, buf: ack, count: 6); |
45 | } |
46 | |
47 | static int pn533_i2c_send_frame(struct pn533 *dev, |
48 | struct sk_buff *out) |
49 | { |
50 | struct pn533_i2c_phy *phy = dev->phy; |
51 | struct i2c_client *client = phy->i2c_dev; |
52 | int rc; |
53 | |
54 | if (phy->hard_fault != 0) |
55 | return phy->hard_fault; |
56 | |
57 | if (phy->priv == NULL) |
58 | phy->priv = dev; |
59 | |
60 | phy->aborted = false; |
61 | |
62 | print_hex_dump_debug("PN533_i2c TX: " , DUMP_PREFIX_NONE, 16, 1, |
63 | out->data, out->len, false); |
64 | |
65 | rc = i2c_master_send(client, buf: out->data, count: out->len); |
66 | |
67 | if (rc == -EREMOTEIO) { /* Retry, chip was in power down */ |
68 | usleep_range(min: 6000, max: 10000); |
69 | rc = i2c_master_send(client, buf: out->data, count: out->len); |
70 | } |
71 | |
72 | if (rc >= 0) { |
73 | if (rc != out->len) |
74 | rc = -EREMOTEIO; |
75 | else |
76 | rc = 0; |
77 | } |
78 | |
79 | return rc; |
80 | } |
81 | |
82 | static void pn533_i2c_abort_cmd(struct pn533 *dev, gfp_t flags) |
83 | { |
84 | struct pn533_i2c_phy *phy = dev->phy; |
85 | |
86 | phy->aborted = true; |
87 | |
88 | /* An ack will cancel the last issued command */ |
89 | pn533_i2c_send_ack(dev, flags); |
90 | |
91 | /* schedule cmd_complete_work to finish current command execution */ |
92 | pn533_recv_frame(dev: phy->priv, NULL, status: -ENOENT); |
93 | } |
94 | |
95 | static int pn533_i2c_read(struct pn533_i2c_phy *phy, struct sk_buff **skb) |
96 | { |
97 | struct i2c_client *client = phy->i2c_dev; |
98 | int len = PN533_EXT_FRAME_HEADER_LEN + |
99 | PN533_STD_FRAME_MAX_PAYLOAD_LEN + |
100 | PN533_STD_FRAME_TAIL_LEN + 1; |
101 | int r; |
102 | |
103 | *skb = alloc_skb(size: len, GFP_KERNEL); |
104 | if (*skb == NULL) |
105 | return -ENOMEM; |
106 | |
107 | r = i2c_master_recv(client, buf: skb_put(skb: *skb, len), count: len); |
108 | if (r != len) { |
109 | nfc_err(&client->dev, "cannot read. r=%d len=%d\n" , r, len); |
110 | kfree_skb(skb: *skb); |
111 | return -EREMOTEIO; |
112 | } |
113 | |
114 | if (!((*skb)->data[0] & 0x01)) { |
115 | nfc_err(&client->dev, "READY flag not set" ); |
116 | kfree_skb(skb: *skb); |
117 | return -EBUSY; |
118 | } |
119 | |
120 | /* remove READY byte */ |
121 | skb_pull(skb: *skb, len: 1); |
122 | /* trim to frame size */ |
123 | skb_trim(skb: *skb, len: phy->priv->ops->rx_frame_size((*skb)->data)); |
124 | |
125 | return 0; |
126 | } |
127 | |
128 | static irqreturn_t pn533_i2c_irq_thread_fn(int irq, void *data) |
129 | { |
130 | struct pn533_i2c_phy *phy = data; |
131 | struct sk_buff *skb = NULL; |
132 | int r; |
133 | |
134 | if (!phy || irq != phy->i2c_dev->irq) { |
135 | WARN_ON_ONCE(1); |
136 | return IRQ_NONE; |
137 | } |
138 | |
139 | if (phy->hard_fault != 0) |
140 | return IRQ_HANDLED; |
141 | |
142 | r = pn533_i2c_read(phy, skb: &skb); |
143 | if (r == -EREMOTEIO) { |
144 | phy->hard_fault = r; |
145 | |
146 | pn533_recv_frame(dev: phy->priv, NULL, status: -EREMOTEIO); |
147 | |
148 | return IRQ_HANDLED; |
149 | } else if ((r == -ENOMEM) || (r == -EBADMSG) || (r == -EBUSY)) { |
150 | return IRQ_HANDLED; |
151 | } |
152 | |
153 | if (!phy->aborted) |
154 | pn533_recv_frame(dev: phy->priv, skb, status: 0); |
155 | |
156 | return IRQ_HANDLED; |
157 | } |
158 | |
159 | static const struct pn533_phy_ops i2c_phy_ops = { |
160 | .send_frame = pn533_i2c_send_frame, |
161 | .send_ack = pn533_i2c_send_ack, |
162 | .abort_cmd = pn533_i2c_abort_cmd, |
163 | }; |
164 | |
165 | |
166 | static int pn533_i2c_probe(struct i2c_client *client) |
167 | { |
168 | struct pn533_i2c_phy *phy; |
169 | struct pn533 *priv; |
170 | int r = 0; |
171 | |
172 | if (!i2c_check_functionality(adap: client->adapter, I2C_FUNC_I2C)) { |
173 | nfc_err(&client->dev, "Need I2C_FUNC_I2C\n" ); |
174 | return -ENODEV; |
175 | } |
176 | |
177 | phy = devm_kzalloc(dev: &client->dev, size: sizeof(struct pn533_i2c_phy), |
178 | GFP_KERNEL); |
179 | if (!phy) |
180 | return -ENOMEM; |
181 | |
182 | phy->i2c_dev = client; |
183 | i2c_set_clientdata(client, data: phy); |
184 | |
185 | priv = pn53x_common_init(PN533_DEVICE_PN532, |
186 | protocol_type: PN533_PROTO_REQ_ACK_RESP, |
187 | phy, phy_ops: &i2c_phy_ops, NULL, |
188 | dev: &phy->i2c_dev->dev); |
189 | |
190 | if (IS_ERR(ptr: priv)) |
191 | return PTR_ERR(ptr: priv); |
192 | |
193 | phy->priv = priv; |
194 | r = pn532_i2c_nfc_alloc(priv, PN533_NO_TYPE_B_PROTOCOLS, parent: &client->dev); |
195 | if (r) |
196 | goto nfc_alloc_err; |
197 | |
198 | r = request_threaded_irq(irq: client->irq, NULL, thread_fn: pn533_i2c_irq_thread_fn, |
199 | IRQF_TRIGGER_FALLING | |
200 | IRQF_SHARED | IRQF_ONESHOT, |
201 | PN533_I2C_DRIVER_NAME, dev: phy); |
202 | if (r < 0) { |
203 | nfc_err(&client->dev, "Unable to register IRQ handler\n" ); |
204 | goto irq_rqst_err; |
205 | } |
206 | |
207 | r = pn533_finalize_setup(dev: priv); |
208 | if (r) |
209 | goto fn_setup_err; |
210 | |
211 | r = nfc_register_device(dev: priv->nfc_dev); |
212 | if (r) |
213 | goto fn_setup_err; |
214 | |
215 | return r; |
216 | |
217 | fn_setup_err: |
218 | free_irq(client->irq, phy); |
219 | |
220 | irq_rqst_err: |
221 | nfc_free_device(dev: priv->nfc_dev); |
222 | |
223 | nfc_alloc_err: |
224 | pn53x_common_clean(priv: phy->priv); |
225 | |
226 | return r; |
227 | } |
228 | |
229 | static void pn533_i2c_remove(struct i2c_client *client) |
230 | { |
231 | struct pn533_i2c_phy *phy = i2c_get_clientdata(client); |
232 | |
233 | free_irq(client->irq, phy); |
234 | |
235 | pn53x_unregister_nfc(priv: phy->priv); |
236 | pn53x_common_clean(priv: phy->priv); |
237 | } |
238 | |
239 | static const struct of_device_id of_pn533_i2c_match[] __maybe_unused = { |
240 | { .compatible = "nxp,pn532" , }, |
241 | /* |
242 | * NOTE: The use of the compatibles with the trailing "...-i2c" is |
243 | * deprecated and will be removed. |
244 | */ |
245 | { .compatible = "nxp,pn533-i2c" , }, |
246 | { .compatible = "nxp,pn532-i2c" , }, |
247 | {}, |
248 | }; |
249 | MODULE_DEVICE_TABLE(of, of_pn533_i2c_match); |
250 | |
251 | static const struct i2c_device_id pn533_i2c_id_table[] = { |
252 | { PN533_I2C_DRIVER_NAME, 0 }, |
253 | {} |
254 | }; |
255 | MODULE_DEVICE_TABLE(i2c, pn533_i2c_id_table); |
256 | |
257 | static struct i2c_driver pn533_i2c_driver = { |
258 | .driver = { |
259 | .name = PN533_I2C_DRIVER_NAME, |
260 | .of_match_table = of_match_ptr(of_pn533_i2c_match), |
261 | }, |
262 | .probe = pn533_i2c_probe, |
263 | .id_table = pn533_i2c_id_table, |
264 | .remove = pn533_i2c_remove, |
265 | }; |
266 | |
267 | module_i2c_driver(pn533_i2c_driver); |
268 | |
269 | MODULE_AUTHOR("Michael Thalmeier <michael.thalmeier@hale.at>" ); |
270 | MODULE_DESCRIPTION("PN533 I2C driver ver " VERSION); |
271 | MODULE_VERSION(VERSION); |
272 | MODULE_LICENSE("GPL" ); |
273 | |