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24#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
25
26#include <linux/delay.h>
27#include <linux/i2c.h>
28#include <linux/interrupt.h>
29#include <linux/miscdevice.h>
30#include <linux/module.h>
31#include <linux/nfc.h>
32#include <linux/of_gpio.h>
33#include <linux/of_irq.h>
34#include <linux/platform_data/nxp-nci.h>
35#include <linux/unaligned/access_ok.h>
36
37#include <net/nfc/nfc.h>
38
39#include "nxp-nci.h"
40
41#define NXP_NCI_I2C_DRIVER_NAME "nxp-nci_i2c"
42
43#define NXP_NCI_I2C_MAX_PAYLOAD 32
44
45struct nxp_nci_i2c_phy {
46 struct i2c_client *i2c_dev;
47 struct nci_dev *ndev;
48
49 unsigned int gpio_en;
50 unsigned int gpio_fw;
51
52 int hard_fault;
53
54
55
56};
57
58static int nxp_nci_i2c_set_mode(void *phy_id,
59 enum nxp_nci_mode mode)
60{
61 struct nxp_nci_i2c_phy *phy = (struct nxp_nci_i2c_phy *) phy_id;
62
63 gpio_set_value(phy->gpio_fw, (mode == NXP_NCI_MODE_FW) ? 1 : 0);
64 gpio_set_value(phy->gpio_en, (mode != NXP_NCI_MODE_COLD) ? 1 : 0);
65 usleep_range(10000, 15000);
66
67 if (mode == NXP_NCI_MODE_COLD)
68 phy->hard_fault = 0;
69
70 return 0;
71}
72
73static int nxp_nci_i2c_write(void *phy_id, struct sk_buff *skb)
74{
75 int r;
76 struct nxp_nci_i2c_phy *phy = phy_id;
77 struct i2c_client *client = phy->i2c_dev;
78
79 if (phy->hard_fault != 0)
80 return phy->hard_fault;
81
82 r = i2c_master_send(client, skb->data, skb->len);
83 if (r == -EREMOTEIO) {
84
85 usleep_range(110000, 120000);
86 r = i2c_master_send(client, skb->data, skb->len);
87 }
88
89 if (r < 0) {
90 nfc_err(&client->dev, "Error %d on I2C send\n", r);
91 } else if (r != skb->len) {
92 nfc_err(&client->dev,
93 "Invalid length sent: %u (expected %u)\n",
94 r, skb->len);
95 r = -EREMOTEIO;
96 } else {
97
98 r = 0;
99 }
100
101 return r;
102}
103
104static struct nxp_nci_phy_ops i2c_phy_ops = {
105 .set_mode = nxp_nci_i2c_set_mode,
106 .write = nxp_nci_i2c_write,
107};
108
109static int nxp_nci_i2c_fw_read(struct nxp_nci_i2c_phy *phy,
110 struct sk_buff **skb)
111{
112 struct i2c_client *client = phy->i2c_dev;
113 u16 header;
114 size_t frame_len;
115 int r;
116
117 r = i2c_master_recv(client, (u8 *) &header, NXP_NCI_FW_HDR_LEN);
118 if (r < 0) {
119 goto fw_read_exit;
120 } else if (r != NXP_NCI_FW_HDR_LEN) {
121 nfc_err(&client->dev, "Incorrect header length: %u\n", r);
122 r = -EBADMSG;
123 goto fw_read_exit;
124 }
125
126 frame_len = (get_unaligned_be16(&header) & NXP_NCI_FW_FRAME_LEN_MASK) +
127 NXP_NCI_FW_CRC_LEN;
128
129 *skb = alloc_skb(NXP_NCI_FW_HDR_LEN + frame_len, GFP_KERNEL);
130 if (*skb == NULL) {
131 r = -ENOMEM;
132 goto fw_read_exit;
133 }
134
135 memcpy(skb_put(*skb, NXP_NCI_FW_HDR_LEN), &header, NXP_NCI_FW_HDR_LEN);
136
137 r = i2c_master_recv(client, skb_put(*skb, frame_len), frame_len);
138 if (r != frame_len) {
139 nfc_err(&client->dev,
140 "Invalid frame length: %u (expected %zu)\n",
141 r, frame_len);
142 r = -EBADMSG;
143 goto fw_read_exit_free_skb;
144 }
145
146 return 0;
147
148fw_read_exit_free_skb:
149 kfree_skb(*skb);
150fw_read_exit:
151 return r;
152}
153
154static int nxp_nci_i2c_nci_read(struct nxp_nci_i2c_phy *phy,
155 struct sk_buff **skb)
156{
157 struct nci_ctrl_hdr header;
158 struct i2c_client *client = phy->i2c_dev;
159 int r;
160
161 r = i2c_master_recv(client, (u8 *) &header, NCI_CTRL_HDR_SIZE);
162 if (r < 0) {
163 goto nci_read_exit;
164 } else if (r != NCI_CTRL_HDR_SIZE) {
165 nfc_err(&client->dev, "Incorrect header length: %u\n", r);
166 r = -EBADMSG;
167 goto nci_read_exit;
168 }
169
170 *skb = alloc_skb(NCI_CTRL_HDR_SIZE + header.plen, GFP_KERNEL);
171 if (*skb == NULL) {
172 r = -ENOMEM;
173 goto nci_read_exit;
174 }
175
176 memcpy(skb_put(*skb, NCI_CTRL_HDR_SIZE), (void *) &header,
177 NCI_CTRL_HDR_SIZE);
178
179 r = i2c_master_recv(client, skb_put(*skb, header.plen), header.plen);
180 if (r != header.plen) {
181 nfc_err(&client->dev,
182 "Invalid frame payload length: %u (expected %u)\n",
183 r, header.plen);
184 r = -EBADMSG;
185 goto nci_read_exit_free_skb;
186 }
187
188 return 0;
189
190nci_read_exit_free_skb:
191 kfree_skb(*skb);
192nci_read_exit:
193 return r;
194}
195
196static irqreturn_t nxp_nci_i2c_irq_thread_fn(int irq, void *phy_id)
197{
198 struct nxp_nci_i2c_phy *phy = phy_id;
199 struct i2c_client *client;
200 struct nxp_nci_info *info;
201
202 struct sk_buff *skb = NULL;
203 int r = 0;
204
205 if (!phy || !phy->ndev)
206 goto exit_irq_none;
207
208 client = phy->i2c_dev;
209
210 if (!client || irq != client->irq)
211 goto exit_irq_none;
212
213 info = nci_get_drvdata(phy->ndev);
214
215 if (!info)
216 goto exit_irq_none;
217
218 mutex_lock(&info->info_lock);
219
220 if (phy->hard_fault != 0)
221 goto exit_irq_handled;
222
223 switch (info->mode) {
224 case NXP_NCI_MODE_NCI:
225 r = nxp_nci_i2c_nci_read(phy, &skb);
226 break;
227 case NXP_NCI_MODE_FW:
228 r = nxp_nci_i2c_fw_read(phy, &skb);
229 break;
230 case NXP_NCI_MODE_COLD:
231 r = -EREMOTEIO;
232 break;
233 }
234
235 if (r == -EREMOTEIO) {
236 phy->hard_fault = r;
237 skb = NULL;
238 } else if (r < 0) {
239 nfc_err(&client->dev, "Read failed with error %d\n", r);
240 goto exit_irq_handled;
241 }
242
243 switch (info->mode) {
244 case NXP_NCI_MODE_NCI:
245 nci_recv_frame(phy->ndev, skb);
246 break;
247 case NXP_NCI_MODE_FW:
248 nxp_nci_fw_recv_frame(phy->ndev, skb);
249 break;
250 case NXP_NCI_MODE_COLD:
251 break;
252 }
253
254exit_irq_handled:
255 mutex_unlock(&info->info_lock);
256 return IRQ_HANDLED;
257exit_irq_none:
258 WARN_ON_ONCE(1);
259 return IRQ_NONE;
260}
261
262#ifdef CONFIG_OF
263
264static int nxp_nci_i2c_parse_devtree(struct i2c_client *client)
265{
266 struct nxp_nci_i2c_phy *phy = i2c_get_clientdata(client);
267 struct device_node *pp;
268 int r;
269
270 pp = client->dev.of_node;
271 if (!pp)
272 return -ENODEV;
273
274 r = of_get_named_gpio(pp, "enable-gpios", 0);
275 if (r == -EPROBE_DEFER)
276 r = of_get_named_gpio(pp, "enable-gpios", 0);
277 if (r < 0) {
278 nfc_err(&client->dev, "Failed to get EN gpio, error: %d\n", r);
279 return r;
280 }
281 phy->gpio_en = r;
282
283 r = of_get_named_gpio(pp, "firmware-gpios", 0);
284 if (r == -EPROBE_DEFER)
285 r = of_get_named_gpio(pp, "firmware-gpios", 0);
286 if (r < 0) {
287 nfc_err(&client->dev, "Failed to get FW gpio, error: %d\n", r);
288 return r;
289 }
290 phy->gpio_fw = r;
291
292 r = irq_of_parse_and_map(pp, 0);
293 if (r < 0) {
294 nfc_err(&client->dev, "Unable to get irq, error: %d\n", r);
295 return r;
296 }
297 client->irq = r;
298
299 return 0;
300}
301
302#else
303
304static int nxp_nci_i2c_parse_devtree(struct i2c_client *client)
305{
306 return -ENODEV;
307}
308
309#endif
310
311static int nxp_nci_i2c_probe(struct i2c_client *client,
312 const struct i2c_device_id *id)
313{
314 struct nxp_nci_i2c_phy *phy;
315 struct nxp_nci_nfc_platform_data *pdata;
316 int r;
317
318 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
319 nfc_err(&client->dev, "Need I2C_FUNC_I2C\n");
320 r = -ENODEV;
321 goto probe_exit;
322 }
323
324 phy = devm_kzalloc(&client->dev, sizeof(struct nxp_nci_i2c_phy),
325 GFP_KERNEL);
326 if (!phy) {
327 r = -ENOMEM;
328 goto probe_exit;
329 }
330
331 phy->i2c_dev = client;
332 i2c_set_clientdata(client, phy);
333
334 pdata = client->dev.platform_data;
335
336 if (!pdata && client->dev.of_node) {
337 r = nxp_nci_i2c_parse_devtree(client);
338 if (r < 0) {
339 nfc_err(&client->dev, "Failed to get DT data\n");
340 goto probe_exit;
341 }
342 } else if (pdata) {
343 phy->gpio_en = pdata->gpio_en;
344 phy->gpio_fw = pdata->gpio_fw;
345 client->irq = pdata->irq;
346 } else {
347 nfc_err(&client->dev, "No platform data\n");
348 r = -EINVAL;
349 goto probe_exit;
350 }
351
352 r = devm_gpio_request_one(&phy->i2c_dev->dev, phy->gpio_en,
353 GPIOF_OUT_INIT_LOW, "nxp_nci_en");
354 if (r < 0)
355 goto probe_exit;
356
357 r = devm_gpio_request_one(&phy->i2c_dev->dev, phy->gpio_fw,
358 GPIOF_OUT_INIT_LOW, "nxp_nci_fw");
359 if (r < 0)
360 goto probe_exit;
361
362 r = nxp_nci_probe(phy, &client->dev, &i2c_phy_ops,
363 NXP_NCI_I2C_MAX_PAYLOAD, &phy->ndev);
364 if (r < 0)
365 goto probe_exit;
366
367 r = request_threaded_irq(client->irq, NULL,
368 nxp_nci_i2c_irq_thread_fn,
369 IRQF_TRIGGER_RISING | IRQF_ONESHOT,
370 NXP_NCI_I2C_DRIVER_NAME, phy);
371 if (r < 0)
372 nfc_err(&client->dev, "Unable to register IRQ handler\n");
373
374probe_exit:
375 return r;
376}
377
378static int nxp_nci_i2c_remove(struct i2c_client *client)
379{
380 struct nxp_nci_i2c_phy *phy = i2c_get_clientdata(client);
381
382 nxp_nci_remove(phy->ndev);
383 free_irq(client->irq, phy);
384
385 return 0;
386}
387
388static struct i2c_device_id nxp_nci_i2c_id_table[] = {
389 {"nxp-nci_i2c", 0},
390 {}
391};
392MODULE_DEVICE_TABLE(i2c, nxp_nci_i2c_id_table);
393
394static const struct of_device_id of_nxp_nci_i2c_match[] = {
395 { .compatible = "nxp,nxp-nci-i2c", },
396 {},
397};
398MODULE_DEVICE_TABLE(of, of_nxp_nci_i2c_match);
399
400static struct i2c_driver nxp_nci_i2c_driver = {
401 .driver = {
402 .name = NXP_NCI_I2C_DRIVER_NAME,
403 .owner = THIS_MODULE,
404 .of_match_table = of_match_ptr(of_nxp_nci_i2c_match),
405 },
406 .probe = nxp_nci_i2c_probe,
407 .id_table = nxp_nci_i2c_id_table,
408 .remove = nxp_nci_i2c_remove,
409};
410
411module_i2c_driver(nxp_nci_i2c_driver);
412
413MODULE_LICENSE("GPL");
414MODULE_DESCRIPTION("I2C driver for NXP NCI NFC controllers");
415MODULE_AUTHOR("Clément Perrochaud <clement.perrochaud@nxp.com>");
416
