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8#include <linux/module.h>
9#include <linux/acpi.h>
10#include <linux/i2c.h>
11#include <linux/interrupt.h>
12#include <linux/nfc.h>
13#include <linux/delay.h>
14#include <linux/gpio/consumer.h>
15#include <net/nfc/nfc.h>
16#include <net/nfc/nci_core.h>
17
18#include "fdp.h"
19
20#define FDP_I2C_DRIVER_NAME "fdp_nci_i2c"
21
22#define FDP_DP_CLOCK_TYPE_NAME "clock-type"
23#define FDP_DP_CLOCK_FREQ_NAME "clock-freq"
24#define FDP_DP_FW_VSC_CFG_NAME "fw-vsc-cfg"
25
26#define FDP_FRAME_HEADROOM 2
27#define FDP_FRAME_TAILROOM 1
28
29#define FDP_NCI_I2C_MIN_PAYLOAD 5
30#define FDP_NCI_I2C_MAX_PAYLOAD 261
31
32#define FDP_POWER_OFF 0
33#define FDP_POWER_ON 1
34
35#define fdp_nci_i2c_dump_skb(dev, prefix, skb) \
36 print_hex_dump(KERN_DEBUG, prefix": ", DUMP_PREFIX_OFFSET, \
37 16, 1, (skb)->data, (skb)->len, 0)
38
39static void fdp_nci_i2c_reset(struct fdp_i2c_phy *phy)
40{
41
42 gpiod_set_value_cansleep(phy->power_gpio, FDP_POWER_OFF);
43 usleep_range(1000, 4000);
44 gpiod_set_value_cansleep(phy->power_gpio, FDP_POWER_ON);
45 usleep_range(10000, 14000);
46}
47
48static int fdp_nci_i2c_enable(void *phy_id)
49{
50 struct fdp_i2c_phy *phy = phy_id;
51
52 dev_dbg(&phy->i2c_dev->dev, "%s\n", __func__);
53 fdp_nci_i2c_reset(phy);
54
55 return 0;
56}
57
58static void fdp_nci_i2c_disable(void *phy_id)
59{
60 struct fdp_i2c_phy *phy = phy_id;
61
62 dev_dbg(&phy->i2c_dev->dev, "%s\n", __func__);
63 fdp_nci_i2c_reset(phy);
64}
65
66static void fdp_nci_i2c_add_len_lrc(struct sk_buff *skb)
67{
68 u8 lrc = 0;
69 u16 len, i;
70
71
72 len = skb->len;
73 *(u8 *)skb_push(skb, 1) = len & 0xff;
74 *(u8 *)skb_push(skb, 1) = len >> 8;
75
76
77 for (i = 0; i < len + 2; i++)
78 lrc ^= skb->data[i];
79
80 skb_put_u8(skb, lrc);
81}
82
83static void fdp_nci_i2c_remove_len_lrc(struct sk_buff *skb)
84{
85 skb_pull(skb, FDP_FRAME_HEADROOM);
86 skb_trim(skb, skb->len - FDP_FRAME_TAILROOM);
87}
88
89static int fdp_nci_i2c_write(void *phy_id, struct sk_buff *skb)
90{
91 struct fdp_i2c_phy *phy = phy_id;
92 struct i2c_client *client = phy->i2c_dev;
93 int r;
94
95 if (phy->hard_fault != 0)
96 return phy->hard_fault;
97
98 fdp_nci_i2c_add_len_lrc(skb);
99 fdp_nci_i2c_dump_skb(&client->dev, "fdp_wr", skb);
100
101 r = i2c_master_send(client, skb->data, skb->len);
102 if (r == -EREMOTEIO) {
103 usleep_range(1000, 4000);
104 r = i2c_master_send(client, skb->data, skb->len);
105 }
106
107 if (r < 0 || r != skb->len)
108 dev_dbg(&client->dev, "%s: error err=%d len=%d\n",
109 __func__, r, skb->len);
110
111 if (r >= 0) {
112 if (r != skb->len) {
113 phy->hard_fault = r;
114 r = -EREMOTEIO;
115 } else {
116 r = 0;
117 }
118 }
119
120 fdp_nci_i2c_remove_len_lrc(skb);
121
122 return r;
123}
124
125static struct nfc_phy_ops i2c_phy_ops = {
126 .write = fdp_nci_i2c_write,
127 .enable = fdp_nci_i2c_enable,
128 .disable = fdp_nci_i2c_disable,
129};
130
131static int fdp_nci_i2c_read(struct fdp_i2c_phy *phy, struct sk_buff **skb)
132{
133 int r, len;
134 u8 tmp[FDP_NCI_I2C_MAX_PAYLOAD], lrc, k;
135 u16 i;
136 struct i2c_client *client = phy->i2c_dev;
137
138 *skb = NULL;
139
140
141 for (k = 0; k < 2; k++) {
142
143 len = phy->next_read_size;
144
145 r = i2c_master_recv(client, tmp, len);
146 if (r != len) {
147 dev_dbg(&client->dev, "%s: i2c recv err: %d\n",
148 __func__, r);
149 goto flush;
150 }
151
152
153 for (lrc = i = 0; i < r; i++)
154 lrc ^= tmp[i];
155
156
157
158
159
160
161 if (lrc) {
162 dev_dbg(&client->dev, "%s: corrupted packet\n",
163 __func__);
164 phy->next_read_size = 5;
165 goto flush;
166 }
167
168
169 if (tmp[0] == 0 && tmp[1] == 0) {
170 phy->next_read_size = (tmp[2] << 8) + tmp[3] + 3;
171 } else {
172 phy->next_read_size = FDP_NCI_I2C_MIN_PAYLOAD;
173
174 *skb = alloc_skb(len, GFP_KERNEL);
175 if (*skb == NULL) {
176 r = -ENOMEM;
177 goto flush;
178 }
179
180 skb_put_data(*skb, tmp, len);
181 fdp_nci_i2c_dump_skb(&client->dev, "fdp_rd", *skb);
182
183 fdp_nci_i2c_remove_len_lrc(*skb);
184 }
185 }
186
187 return 0;
188
189flush:
190
191 if (i2c_master_recv(client, tmp, sizeof(tmp)) < 0)
192 r = -EREMOTEIO;
193
194 return r;
195}
196
197static irqreturn_t fdp_nci_i2c_irq_thread_fn(int irq, void *phy_id)
198{
199 struct fdp_i2c_phy *phy = phy_id;
200 struct i2c_client *client;
201 struct sk_buff *skb;
202 int r;
203
204 if (!phy || irq != phy->i2c_dev->irq) {
205 WARN_ON_ONCE(1);
206 return IRQ_NONE;
207 }
208
209 client = phy->i2c_dev;
210 dev_dbg(&client->dev, "%s\n", __func__);
211
212 r = fdp_nci_i2c_read(phy, &skb);
213
214 if (r == -EREMOTEIO)
215 return IRQ_HANDLED;
216 else if (r == -ENOMEM || r == -EBADMSG)
217 return IRQ_HANDLED;
218
219 if (skb != NULL)
220 fdp_nci_recv_frame(phy->ndev, skb);
221
222 return IRQ_HANDLED;
223}
224
225static void fdp_nci_i2c_read_device_properties(struct device *dev,
226 u8 *clock_type, u32 *clock_freq,
227 u8 **fw_vsc_cfg)
228{
229 int r;
230 u8 len;
231
232 r = device_property_read_u8(dev, FDP_DP_CLOCK_TYPE_NAME, clock_type);
233 if (r) {
234 dev_dbg(dev, "Using default clock type");
235 *clock_type = 0;
236 }
237
238 r = device_property_read_u32(dev, FDP_DP_CLOCK_FREQ_NAME, clock_freq);
239 if (r) {
240 dev_dbg(dev, "Using default clock frequency\n");
241 *clock_freq = 26000;
242 }
243
244 if (device_property_present(dev, FDP_DP_FW_VSC_CFG_NAME)) {
245 r = device_property_read_u8(dev, FDP_DP_FW_VSC_CFG_NAME,
246 &len);
247
248 if (r || len <= 0)
249 goto vsc_read_err;
250
251
252 len++;
253
254 *fw_vsc_cfg = devm_kmalloc_array(dev,
255 len, sizeof(**fw_vsc_cfg),
256 GFP_KERNEL);
257
258 r = device_property_read_u8_array(dev, FDP_DP_FW_VSC_CFG_NAME,
259 *fw_vsc_cfg, len);
260
261 if (r) {
262 devm_kfree(dev, *fw_vsc_cfg);
263 goto vsc_read_err;
264 }
265 } else {
266vsc_read_err:
267 dev_dbg(dev, "FW vendor specific commands not present\n");
268 *fw_vsc_cfg = NULL;
269 }
270
271 dev_dbg(dev, "Clock type: %d, clock frequency: %d, VSC: %s",
272 *clock_type, *clock_freq, *fw_vsc_cfg != NULL ? "yes" : "no");
273}
274
275static const struct acpi_gpio_params power_gpios = { 0, 0, false };
276
277static const struct acpi_gpio_mapping acpi_fdp_gpios[] = {
278 { "power-gpios", &power_gpios, 1 },
279 {},
280};
281
282static int fdp_nci_i2c_probe(struct i2c_client *client)
283{
284 struct fdp_i2c_phy *phy;
285 struct device *dev = &client->dev;
286 u8 *fw_vsc_cfg;
287 u8 clock_type;
288 u32 clock_freq;
289 int r = 0;
290
291 dev_dbg(dev, "%s\n", __func__);
292
293 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
294 nfc_err(dev, "No I2C_FUNC_I2C support\n");
295 return -ENODEV;
296 }
297
298
299 if (client->irq <= 0) {
300 nfc_err(dev, "IRQ not present\n");
301 return -ENODEV;
302 }
303
304 phy = devm_kzalloc(dev, sizeof(struct fdp_i2c_phy), GFP_KERNEL);
305 if (!phy)
306 return -ENOMEM;
307
308 phy->i2c_dev = client;
309 phy->next_read_size = FDP_NCI_I2C_MIN_PAYLOAD;
310 i2c_set_clientdata(client, phy);
311
312 r = devm_request_threaded_irq(dev, client->irq,
313 NULL, fdp_nci_i2c_irq_thread_fn,
314 IRQF_TRIGGER_RISING | IRQF_ONESHOT,
315 FDP_I2C_DRIVER_NAME, phy);
316
317 if (r < 0) {
318 nfc_err(&client->dev, "Unable to register IRQ handler\n");
319 return r;
320 }
321
322 r = devm_acpi_dev_add_driver_gpios(dev, acpi_fdp_gpios);
323 if (r)
324 dev_dbg(dev, "Unable to add GPIO mapping table\n");
325
326
327 phy->power_gpio = devm_gpiod_get(dev, "power", GPIOD_OUT_LOW);
328 if (IS_ERR(phy->power_gpio)) {
329 nfc_err(dev, "Power GPIO request failed\n");
330 return PTR_ERR(phy->power_gpio);
331 }
332
333
334 fdp_nci_i2c_read_device_properties(dev, &clock_type, &clock_freq,
335 &fw_vsc_cfg);
336
337
338 r = fdp_nci_probe(phy, &i2c_phy_ops, &phy->ndev,
339 FDP_FRAME_HEADROOM, FDP_FRAME_TAILROOM,
340 clock_type, clock_freq, fw_vsc_cfg);
341 if (r < 0) {
342 nfc_err(dev, "NCI probing error\n");
343 return r;
344 }
345
346 dev_dbg(dev, "I2C driver loaded\n");
347 return 0;
348}
349
350static int fdp_nci_i2c_remove(struct i2c_client *client)
351{
352 struct fdp_i2c_phy *phy = i2c_get_clientdata(client);
353
354 dev_dbg(&client->dev, "%s\n", __func__);
355
356 fdp_nci_remove(phy->ndev);
357 fdp_nci_i2c_disable(phy);
358
359 return 0;
360}
361
362static const struct acpi_device_id fdp_nci_i2c_acpi_match[] = {
363 {"INT339A", 0},
364 {}
365};
366MODULE_DEVICE_TABLE(acpi, fdp_nci_i2c_acpi_match);
367
368static struct i2c_driver fdp_nci_i2c_driver = {
369 .driver = {
370 .name = FDP_I2C_DRIVER_NAME,
371 .acpi_match_table = ACPI_PTR(fdp_nci_i2c_acpi_match),
372 },
373 .probe_new = fdp_nci_i2c_probe,
374 .remove = fdp_nci_i2c_remove,
375};
376module_i2c_driver(fdp_nci_i2c_driver);
377
378MODULE_LICENSE("GPL");
379MODULE_DESCRIPTION("I2C driver for Intel Fields Peak NFC controller");
380MODULE_AUTHOR("Robert Dolca <robert.dolca@intel.com>");
381
