1 /** ----------------------------------------------------------------------
2 *
3 * Copyright (C) 2013 ST Microelectronics S.A.
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 *
17 *
18 ----------------------------------------------------------------------*/
19
20 #include <assert.h>
21 #include <errno.h>
22 #include <fcntl.h>
23 #include <limits.h>
24 #include <linux/input.h> /* not required for all builds */
25 #include <poll.h>
26 #include <pthread.h>
27 #include <stdint.h>
28 #include <stdio.h>
29 #include <stdlib.h>
30 #include <string.h>
31 #include <sys/ioctl.h>
32 #include <unistd.h>
33
34 #include "android_logmsg.h"
35 #include "halcore.h"
36 #include "halcore_private.h"
37
38 #define ST21NFC_MAGIC 0xEA
39
40 #define ST21NFC_GET_WAKEUP _IOR(ST21NFC_MAGIC, 0x01, unsigned int)
41 #define ST21NFC_PULSE_RESET _IOR(ST21NFC_MAGIC, 0x02, unsigned int)
42 #define ST21NFC_SET_POLARITY_RISING _IOR(ST21NFC_MAGIC, 0x03, unsigned int)
43 #define ST21NFC_SET_POLARITY_FALLING _IOR(ST21NFC_MAGIC, 0x04, unsigned int)
44 #define ST21NFC_SET_POLARITY_HIGH _IOR(ST21NFC_MAGIC, 0x05, unsigned int)
45 #define ST21NFC_SET_POLARITY_LOW _IOR(ST21NFC_MAGIC, 0x06, unsigned int)
46
47 #define LINUX_DBGBUFFER_SIZE 300
48
49 static int fidI2c = 0;
50 static int cmdPipe[2] = {0, 0};
51
52 static struct pollfd event_table[2];
53 static pthread_t threadHandle = (pthread_t)NULL;
54 pthread_mutex_t i2ctransport_mtx = PTHREAD_MUTEX_INITIALIZER;
55
56 /**************************************************************************************************
57 *
58 * Private API Declaration
59 *
60 **************************************************************************************************/
61
62 static int i2cSetPolarity(int fid, bool low, bool edge);
63 static int i2cResetPulse(int fid);
64 static int i2cRead(int fid, uint8_t* pvBuffer, int length);
65 static int i2cGetGPIOState(int fid);
66 static int i2cWrite(int fd, const uint8_t* pvBuffer, int length);
67
68 /**************************************************************************************************
69 *
70 * Public API Entry-Points
71 *
72 **************************************************************************************************/
73
74 /**
75 * Worker thread for I2C data processing.
76 * On exit of this thread, destroy the HAL thread instance.
77 * @param arg Handle of the HAL layer
78 */
I2cWorkerThread(void * arg)79 static void* I2cWorkerThread(void* arg) {
80 bool closeThread = false;
81 HALHANDLE hHAL = (HALHANDLE)arg;
82 STLOG_HAL_D("echo thread started...\n");
83 bool readOk = false;
84
85 do {
86 event_table[0].fd = fidI2c;
87 event_table[0].events = POLLIN;
88 event_table[0].revents = 0;
89
90 event_table[1].fd = cmdPipe[0];
91 event_table[1].events = POLLIN;
92 event_table[1].revents = 0;
93
94 STLOG_HAL_V("echo thread go to sleep...\n");
95
96 int poll_status = poll(event_table, 2, -1);
97
98 if (-1 == poll_status) {
99 STLOG_HAL_E("error in poll call\n");
100 break;
101 }
102
103 if (event_table[0].revents & POLLIN) {
104 STLOG_HAL_V("echo thread wakeup from chip...\n");
105
106 uint8_t buffer[300];
107
108 do {
109 // load first four bytes:
110 int bytesRead = i2cRead(fidI2c, buffer, 3);
111
112 if (bytesRead == 3) {
113 if ((buffer[0] != 0x7E) && (buffer[1] != 0x7E)) {
114 readOk = true;
115 } else {
116 if (buffer[1] != 0x7E) {
117 STLOG_HAL_W(
118 "Idle data: 2nd byte is 0x%02x\n, reading next 2 bytes",
119 buffer[1]);
120 buffer[0] = buffer[1];
121 buffer[1] = buffer[2];
122 bytesRead = i2cRead(fidI2c, buffer + 2, 1);
123 if (bytesRead == 1) {
124 readOk = true;
125 }
126 } else if (buffer[2] != 0x7E) {
127 STLOG_HAL_W("Idle data: 3rd byte is 0x%02x\n, reading next byte",
128 buffer[2]);
129 buffer[0] = buffer[2];
130 bytesRead = i2cRead(fidI2c, buffer + 1, 2);
131 if (bytesRead == 2) {
132 readOk = true;
133 }
134 } else {
135 STLOG_HAL_W("received idle data\n");
136 }
137 }
138
139 if (readOk == true) {
140 int remaining = buffer[2];
141 bytesRead = 0;
142 if (remaining != 0) {
143 // read and pass to HALCore
144 bytesRead = i2cRead(fidI2c, buffer + 3, remaining);
145 }
146 if (bytesRead == remaining) {
147 DispHal("RX DATA", buffer, 3 + bytesRead);
148 HalSendUpstream(hHAL, buffer, 3 + bytesRead);
149 } else {
150 readOk = false;
151 STLOG_HAL_E("! didn't read expected bytes from i2c\n");
152 }
153 }
154
155 } else {
156 STLOG_HAL_E("! didn't read 3 requested bytes from i2c\n");
157 }
158
159 readOk = false;
160 memset(buffer, 0xca, sizeof(buffer));
161
162 /* read while we have data available */
163 } while (i2cGetGPIOState(fidI2c) == 1);
164 }
165
166 if (event_table[1].revents & POLLIN) {
167 STLOG_HAL_V("thread received command.. \n");
168
169 char cmd = 0;
170 read(cmdPipe[0], &cmd, 1);
171
172 switch (cmd) {
173 case 'X':
174 STLOG_HAL_D("received close command\n");
175 closeThread = true;
176 break;
177
178 case 'W': {
179 size_t length;
180 uint8_t buffer[MAX_BUFFER_SIZE];
181 STLOG_HAL_V("received write command\n");
182 read(cmdPipe[0], &length, sizeof(length));
183 if (length <= MAX_BUFFER_SIZE) {
184 read(cmdPipe[0], buffer, length);
185 i2cWrite(fidI2c, buffer, length);
186 } else {
187 STLOG_HAL_E(
188 "! received bigger data than expected!! Data not transmitted "
189 "to NFCC \n");
190 size_t bytes_read = 1;
191 // Read all the data to empty but do not use it as not expected
192 while ((bytes_read > 0) && (length > 0)) {
193 bytes_read = read(cmdPipe[0], buffer, MAX_BUFFER_SIZE);
194 length = length - bytes_read;
195 }
196 }
197 } break;
198 }
199 }
200
201 } while (!closeThread);
202
203 close(fidI2c);
204 close(cmdPipe[0]);
205 close(cmdPipe[1]);
206
207 HalDestroy(hHAL);
208 STLOG_HAL_D("thread exit\n");
209 return 0;
210 }
211
212 /**
213 * Put command into queue for worker thread to process it.
214 * @param x Command 'X' to close I2C layer or 'W' to write data down to I2C
215 * layer followed by data frame
216 * @param len Size of command or data
217 * @return
218 */
I2cWriteCmd(const uint8_t * x,size_t len)219 int I2cWriteCmd(const uint8_t* x, size_t len) {
220 return write(cmdPipe[1], x, len);
221 }
222
223 /**
224 * Initialize the I2C layer.
225 * @param dev NFC NCI device context, NFC callbacks for control/data, HAL handle
226 * @param callb HAL Core callback upon reception on I2C
227 * @param pHandle HAL context handle
228 */
I2cOpenLayer(void * dev,HAL_CALLBACK callb,HALHANDLE * pHandle)229 bool I2cOpenLayer(void* dev, HAL_CALLBACK callb, HALHANDLE* pHandle) {
230 uint32_t NoDbgFlag = HAL_FLAG_DEBUG;
231
232 (void)pthread_mutex_lock(&i2ctransport_mtx);
233 fidI2c = open("/dev/st21nfc", O_RDWR);
234 if (fidI2c < 0) {
235 STLOG_HAL_W("unable to open /dev/st21nfc (%s) \n", strerror(errno));
236 (void)pthread_mutex_unlock(&i2ctransport_mtx);
237 return false;
238 }
239
240 i2cSetPolarity(fidI2c, false, false);
241 i2cResetPulse(fidI2c);
242
243 if ((pipe(cmdPipe) == -1)) {
244 STLOG_HAL_W("unable to open cmdpipe\n");
245 (void)pthread_mutex_unlock(&i2ctransport_mtx);
246 return false;
247 }
248
249 *pHandle = HalCreate(dev, callb, NoDbgFlag);
250
251 if (!*pHandle) {
252 STLOG_HAL_E("failed to create NFC HAL Core \n");
253 (void)pthread_mutex_unlock(&i2ctransport_mtx);
254 return false;
255 }
256
257 (void)pthread_mutex_unlock(&i2ctransport_mtx);
258
259 return (pthread_create(&threadHandle, NULL, I2cWorkerThread, *pHandle) == 0);
260 }
261
262 /**
263 * Terminates the I2C layer.
264 */
I2cCloseLayer()265 void I2cCloseLayer() {
266 uint8_t cmd = 'X';
267 int ret;
268 ALOGD("%s: enter\n", __func__);
269
270 (void)pthread_mutex_lock(&i2ctransport_mtx);
271
272 if (threadHandle == (pthread_t)NULL) {
273 (void)pthread_mutex_unlock(&i2ctransport_mtx);
274 return;
275 }
276
277 I2cWriteCmd(&cmd, sizeof(cmd));
278 /* wait for terminate */
279 ret = pthread_join(threadHandle, (void**)NULL);
280 if (ret != 0) {
281 ALOGE("%s: failed to wait for thread (%d)", __func__, ret);
282 }
283 threadHandle = (pthread_t)NULL;
284 (void)pthread_mutex_unlock(&i2ctransport_mtx);
285 }
286
287 /**
288 * Terminates the I2C layer.
289 */
I2cResetPulse()290 void I2cResetPulse() {
291 ALOGD("%s: enter\n", __func__);
292
293 (void)pthread_mutex_lock(&i2ctransport_mtx);
294
295 i2cResetPulse(fidI2c);
296 (void)pthread_mutex_unlock(&i2ctransport_mtx);
297 }
298 /**************************************************************************************************
299 *
300 * Private API Definition
301 *
302 **************************************************************************************************/
303 /**
304 * Call the st21nfc driver to adjust wake-up polarity.
305 * @param fid File descriptor for NFC device
306 * @param low Polarity (HIGH or LOW)
307 * @param edge Polarity (RISING or FALLING)
308 * @return Result of IOCTL system call (0 if ok)
309 */
i2cSetPolarity(int fid,bool low,bool edge)310 static int i2cSetPolarity(int fid, bool low, bool edge) {
311 int result;
312 unsigned int io_code;
313
314 if (low) {
315 if (edge) {
316 io_code = ST21NFC_SET_POLARITY_FALLING;
317 } else {
318 io_code = ST21NFC_SET_POLARITY_LOW;
319 }
320
321 } else {
322 if (edge) {
323 io_code = ST21NFC_SET_POLARITY_RISING;
324 } else {
325 io_code = ST21NFC_SET_POLARITY_HIGH;
326 }
327 }
328
329 if (-1 == (result = ioctl(fid, io_code, NULL))) {
330 result = -1;
331 }
332
333 return result;
334 } /* i2cSetPolarity*/
335
336 /**
337 * Call the st21nfc driver to generate a 30ms pulse on RESET line.
338 * @param fid File descriptor for NFC device
339 * @return Result of IOCTL system call (0 if ok)
340 */
i2cResetPulse(int fid)341 static int i2cResetPulse(int fid) {
342 int result;
343
344 if (-1 == (result = ioctl(fid, ST21NFC_PULSE_RESET, NULL))) {
345 result = -1;
346 }
347 STLOG_HAL_D("! i2cResetPulse!!, result = %d", result);
348 return result;
349 } /* i2cResetPulse*/
350
351 /**
352 * Write data to st21nfc, on failure do max 3 retries.
353 * @param fid File descriptor for NFC device
354 * @param pvBuffer Data to write
355 * @param length Data size
356 * @return 0 if bytes written, -1 if error
357 */
i2cWrite(int fid,const uint8_t * pvBuffer,int length)358 static int i2cWrite(int fid, const uint8_t* pvBuffer, int length) {
359 int retries = 0;
360 int result = 0;
361 int halfsecs = 0;
362
363 redo:
364 while (retries < 3) {
365 result = write(fid, pvBuffer, length);
366
367 if (result < 0) {
368 char msg[LINUX_DBGBUFFER_SIZE];
369
370 strerror_r(errno, msg, LINUX_DBGBUFFER_SIZE);
371 STLOG_HAL_W("! i2cWrite!!, errno is '%s'", msg);
372 usleep(4000);
373 retries++;
374 } else if (result > 0) {
375 result = 0;
376 return result;
377 } else {
378 STLOG_HAL_W("write on i2c failed, retrying\n");
379 usleep(4000);
380 retries++;
381 }
382 }
383 /* If we're here, we failed to write to NFCC. Retry after 500ms because some
384 CPUs have shown such long unavailability sometimes */
385 if (halfsecs < 10) {
386 usleep(500000);
387 halfsecs++;
388 goto redo;
389 }
390 /* The CLF did not recover, give up */
391 return -1;
392 } /* i2cWrite */
393
394 /**
395 * Read data from st21nfc, on failure do max 3 retries.
396 *
397 * @param fid File descriptor for NFC device
398 * @param pvBuffer Buffer where to copy read data
399 * @param length Data size to read
400 * @return Length of read data, -1 if error
401 */
i2cRead(int fid,uint8_t * pvBuffer,int length)402 static int i2cRead(int fid, uint8_t* pvBuffer, int length) {
403 int retries = 0;
404 int result = -1;
405
406 while ((retries < 3) && (result < 0)) {
407 result = read(fid, pvBuffer, length);
408
409 if (result == -1) {
410 int e = errno;
411 if (e == EAGAIN) {
412 /* File is nonblocking, and no data is available.
413 * This is not an error condition!
414 */
415 result = 0;
416 STLOG_HAL_D(
417 "## i2cRead - got EAGAIN. No data available. return 0 bytes");
418 } else {
419 /* unexpected result */
420 char msg[LINUX_DBGBUFFER_SIZE];
421 strerror_r(e, msg, LINUX_DBGBUFFER_SIZE);
422 STLOG_HAL_W("## i2cRead returns %d errno %d (%s)", result, e, msg);
423 }
424 }
425
426 if (result < 0) {
427 if (retries < 3) {
428 /* delays are different and increasing for the three retries. */
429 static const uint8_t delayTab[] = {2, 3, 5};
430 int delay = delayTab[retries];
431
432 retries++;
433 STLOG_HAL_W("## i2cRead retry %d/3 in %d milliseconds.", retries,
434 delay);
435 usleep(delay * 1000);
436 continue;
437 }
438 }
439 }
440 return result;
441 } /* i2cRead */
442
443 /**
444 * Get the activation status of wake-up pin from st21nfc.
445 * The decision 'active' depends on selected polarity.
446 * The decision is handled inside the driver(st21nfc).
447 * @param fid File descriptor for NFC device
448 * @return
449 * Result < 0: Error condition
450 * Result > 0: Pin active
451 * Result = 0: Pin not active
452 */
i2cGetGPIOState(int fid)453 static int i2cGetGPIOState(int fid) {
454 int result;
455
456 if (-1 == (result = ioctl(fid, ST21NFC_GET_WAKEUP, NULL))) {
457 result = -1;
458 }
459
460 return result;
461 } /* i2cGetGPIOState */
462