1 /*
2  * Copyright (c) 2020 Intel Corporation
3  *
4  * SPDX-License-Identifier: Apache-2.0
5  */
6 
7 #define DT_DRV_COMPAT zephyr_gsm_ppp
8 
9 #include <zephyr/logging/log.h>
10 LOG_MODULE_REGISTER(modem_gsm, CONFIG_MODEM_LOG_LEVEL);
11 
12 #include <stdlib.h>
13 #include <zephyr/kernel.h>
14 #include <zephyr/device.h>
15 #include <zephyr/sys/ring_buffer.h>
16 #include <zephyr/sys/util.h>
17 #include <zephyr/net/ppp.h>
18 #include <zephyr/drivers/modem/gsm_ppp.h>
19 #include <zephyr/drivers/uart.h>
20 #include <zephyr/drivers/console/uart_mux.h>
21 
22 #include "modem_context.h"
23 #include "modem_iface_uart.h"
24 #include "modem_cmd_handler.h"
25 #include "../console/gsm_mux.h"
26 
27 #include <stdio.h>
28 
29 #define GSM_UART_NODE                   DT_INST_BUS(0)
30 #define GSM_CMD_READ_BUF                128
31 #define GSM_CMD_AT_TIMEOUT              K_SECONDS(2)
32 #define GSM_CMD_SETUP_TIMEOUT           K_SECONDS(6)
33 /* GSM_CMD_LOCK_TIMEOUT should be longer than GSM_CMD_AT_TIMEOUT & GSM_CMD_SETUP_TIMEOUT,
34  * otherwise the gsm_ppp_stop might fail to lock tx.
35  */
36 #define GSM_CMD_LOCK_TIMEOUT            K_SECONDS(10)
37 #define GSM_RECV_MAX_BUF                30
38 #define GSM_RECV_BUF_SIZE               128
39 #define GSM_ATTACH_RETRY_DELAY_MSEC     1000
40 #define GSM_REGISTER_DELAY_MSEC         1000
41 #define GSM_RETRY_DELAY                 K_SECONDS(1)
42 
43 #define GSM_RSSI_RETRY_DELAY_MSEC       2000
44 #define GSM_RSSI_RETRIES                10
45 #define GSM_RSSI_INVALID                -1000
46 
47 #if defined(CONFIG_MODEM_GSM_ENABLE_CESQ_RSSI)
48 	#define GSM_RSSI_MAXVAL          0
49 #else
50 	#define GSM_RSSI_MAXVAL         -51
51 #endif
52 
53 /* Modem network registration state */
54 enum network_state {
55 	GSM_NET_INIT = -1,
56 	GSM_NET_NOT_REGISTERED,
57 	GSM_NET_HOME_NETWORK,
58 	GSM_NET_SEARCHING,
59 	GSM_NET_REGISTRATION_DENIED,
60 	GSM_NET_UNKNOWN,
61 	GSM_NET_ROAMING,
62 };
63 
64 static struct gsm_modem {
65 	struct k_mutex lock;
66 	const struct device *dev;
67 	struct modem_context context;
68 
69 	struct modem_cmd_handler_data cmd_handler_data;
70 	uint8_t cmd_match_buf[GSM_CMD_READ_BUF];
71 	struct k_sem sem_response;
72 	struct k_sem sem_if_down;
73 
74 	struct modem_iface_uart_data gsm_data;
75 	struct k_work_delayable gsm_configure_work;
76 	char gsm_rx_rb_buf[PPP_MRU * 3];
77 
78 	uint8_t *ppp_recv_buf;
79 	size_t ppp_recv_buf_len;
80 
81 	enum gsm_ppp_state {
82 		GSM_PPP_START,
83 		GSM_PPP_WAIT_AT,
84 		GSM_PPP_AT_RDY,
85 		GSM_PPP_STATE_INIT,
86 		GSM_PPP_STATE_CONTROL_CHANNEL = GSM_PPP_STATE_INIT,
87 		GSM_PPP_STATE_PPP_CHANNEL,
88 		GSM_PPP_STATE_AT_CHANNEL,
89 		GSM_PPP_STATE_DONE,
90 		GSM_PPP_SETUP = GSM_PPP_STATE_DONE,
91 		GSM_PPP_REGISTERING,
92 		GSM_PPP_ATTACHING,
93 		GSM_PPP_ATTACHED,
94 		GSM_PPP_SETUP_DONE,
95 		GSM_PPP_STOP,
96 		GSM_PPP_STATE_ERROR,
97 	} state;
98 
99 	const struct device *ppp_dev;
100 	const struct device *at_dev;
101 	const struct device *control_dev;
102 
103 	struct net_if *iface;
104 
105 	struct k_thread rx_thread;
106 	struct k_work_q workq;
107 	struct k_work_delayable rssi_work_handle;
108 	struct gsm_ppp_modem_info minfo;
109 
110 	enum network_state net_state;
111 
112 	int retries;
113 	bool modem_info_queried : 1;
114 
115 	void *user_data;
116 
117 	gsm_modem_power_cb modem_on_cb;
118 	gsm_modem_power_cb modem_off_cb;
119 	struct net_mgmt_event_callback gsm_mgmt_cb;
120 } modem;
121 
122 NET_BUF_POOL_DEFINE(gsm_recv_pool, GSM_RECV_MAX_BUF, GSM_RECV_BUF_SIZE, 0, NULL);
123 K_KERNEL_STACK_DEFINE(gsm_rx_stack, CONFIG_MODEM_GSM_RX_STACK_SIZE);
124 K_KERNEL_STACK_DEFINE(gsm_workq_stack, CONFIG_MODEM_GSM_WORKQ_STACK_SIZE);
125 
gsm_ppp_lock(struct gsm_modem * gsm)126 static inline void gsm_ppp_lock(struct gsm_modem *gsm)
127 {
128 	(void)k_mutex_lock(&gsm->lock, K_FOREVER);
129 }
130 
gsm_ppp_unlock(struct gsm_modem * gsm)131 static inline void gsm_ppp_unlock(struct gsm_modem *gsm)
132 {
133 	(void)k_mutex_unlock(&gsm->lock);
134 }
135 
gsm_work_reschedule(struct k_work_delayable * dwork,k_timeout_t delay)136 static inline int gsm_work_reschedule(struct k_work_delayable *dwork, k_timeout_t delay)
137 {
138 	return k_work_reschedule_for_queue(&modem.workq, dwork, delay);
139 }
140 
141 #if defined(CONFIG_MODEM_GSM_ENABLE_CESQ_RSSI)
142 	/* helper macro to keep readability */
143 #define ATOI(s_, value_, desc_) modem_atoi(s_, value_, desc_, __func__)
144 
145 /**
146  * @brief  Convert string to long integer, but handle errors
147  *
148  * @param  s: string with representation of integer number
149  * @param  err_value: on error return this value instead
150  * @param  desc: name the string being converted
151  * @param  func: function where this is called (typically __func__)
152  *
153  * @retval return integer conversion on success, or err_value on error
154  */
modem_atoi(const char * s,const int err_value,const char * desc,const char * func)155 static int modem_atoi(const char *s, const int err_value,
156 				const char *desc, const char *func)
157 {
158 	int ret;
159 	char *endptr;
160 
161 	ret = (int)strtol(s, &endptr, 10);
162 	if ((endptr == NULL) || (*endptr != '\0')) {
163 		LOG_ERR("bad %s '%s' in %s", s,
164 			 desc, func);
165 		return err_value;
166 	}
167 
168 	return ret;
169 }
170 #endif
171 
gsm_rx(struct gsm_modem * gsm)172 static void gsm_rx(struct gsm_modem *gsm)
173 {
174 	LOG_DBG("starting");
175 
176 	while (true) {
177 		modem_iface_uart_rx_wait(&gsm->context.iface, K_FOREVER);
178 
179 		/* The handler will listen AT channel */
180 		modem_cmd_handler_process(&gsm->context.cmd_handler, &gsm->context.iface);
181 	}
182 }
183 
MODEM_CMD_DEFINE(gsm_cmd_ok)184 MODEM_CMD_DEFINE(gsm_cmd_ok)
185 {
186 	(void)modem_cmd_handler_set_error(data, 0);
187 	LOG_DBG("ok");
188 	k_sem_give(&modem.sem_response);
189 	return 0;
190 }
191 
MODEM_CMD_DEFINE(gsm_cmd_error)192 MODEM_CMD_DEFINE(gsm_cmd_error)
193 {
194 	(void)modem_cmd_handler_set_error(data, -EINVAL);
195 	LOG_DBG("error");
196 	k_sem_give(&modem.sem_response);
197 	return 0;
198 }
199 
200 /* Handler: +CME Error: <err>[0] */
MODEM_CMD_DEFINE(gsm_cmd_exterror)201 MODEM_CMD_DEFINE(gsm_cmd_exterror)
202 {
203 	/* TODO: map extended error codes to values */
204 	(void)modem_cmd_handler_set_error(data, -EIO);
205 	k_sem_give(&modem.sem_response);
206 	return 0;
207 }
208 
209 static const struct modem_cmd response_cmds[] = {
210 	MODEM_CMD("OK", gsm_cmd_ok, 0U, ""),
211 	MODEM_CMD("ERROR", gsm_cmd_error, 0U, ""),
212 	MODEM_CMD("+CME ERROR: ", gsm_cmd_exterror, 1U, ""),
213 	MODEM_CMD("CONNECT", gsm_cmd_ok, 0U, ""),
214 };
215 
unquoted_atoi(const char * s,int base)216 static int unquoted_atoi(const char *s, int base)
217 {
218 	if (*s == '"') {
219 		s++;
220 	}
221 
222 	return strtol(s, NULL, base);
223 }
224 
225 /*
226  * Handler: +COPS: <mode>[0],<format>[1],<oper>[2]
227  */
MODEM_CMD_DEFINE(on_cmd_atcmdinfo_cops)228 MODEM_CMD_DEFINE(on_cmd_atcmdinfo_cops)
229 {
230 	if (argc >= 1) {
231 #if defined(CONFIG_MODEM_CELL_INFO)
232 		if (argc >= 3) {
233 			modem.context.data_operator = unquoted_atoi(argv[2], 10);
234 			LOG_INF("operator: %u",
235 				modem.context.data_operator);
236 		}
237 #endif
238 		if (unquoted_atoi(argv[0], 10) == 0) {
239 			modem.context.is_automatic_oper = true;
240 		} else {
241 			modem.context.is_automatic_oper = false;
242 		}
243 	}
244 
245 	return 0;
246 }
247 
248 /*
249  * Provide modem info if modem shell is enabled. This can be shown with
250  * "modem list" shell command.
251  */
252 
253 /* Handler: <manufacturer> */
MODEM_CMD_DEFINE(on_cmd_atcmdinfo_manufacturer)254 MODEM_CMD_DEFINE(on_cmd_atcmdinfo_manufacturer)
255 {
256 	size_t out_len;
257 
258 	out_len = net_buf_linearize(modem.minfo.mdm_manufacturer,
259 				    sizeof(modem.minfo.mdm_manufacturer) - 1,
260 				    data->rx_buf, 0, len);
261 	modem.minfo.mdm_manufacturer[out_len] = '\0';
262 	LOG_INF("Manufacturer: %s", modem.minfo.mdm_manufacturer);
263 
264 	return 0;
265 }
266 
267 /* Handler: <model> */
MODEM_CMD_DEFINE(on_cmd_atcmdinfo_model)268 MODEM_CMD_DEFINE(on_cmd_atcmdinfo_model)
269 {
270 	size_t out_len;
271 
272 	out_len = net_buf_linearize(modem.minfo.mdm_model,
273 				    sizeof(modem.minfo.mdm_model) - 1,
274 				    data->rx_buf, 0, len);
275 	modem.minfo.mdm_model[out_len] = '\0';
276 	LOG_INF("Model: %s", modem.minfo.mdm_model);
277 
278 	return 0;
279 }
280 
281 /* Handler: <rev> */
MODEM_CMD_DEFINE(on_cmd_atcmdinfo_revision)282 MODEM_CMD_DEFINE(on_cmd_atcmdinfo_revision)
283 {
284 	size_t out_len;
285 
286 	out_len = net_buf_linearize(modem.minfo.mdm_revision,
287 				    sizeof(modem.minfo.mdm_revision) - 1,
288 				    data->rx_buf, 0, len);
289 	modem.minfo.mdm_revision[out_len] = '\0';
290 	LOG_INF("Revision: %s", modem.minfo.mdm_revision);
291 
292 	return 0;
293 }
294 
295 /* Handler: <IMEI> */
MODEM_CMD_DEFINE(on_cmd_atcmdinfo_imei)296 MODEM_CMD_DEFINE(on_cmd_atcmdinfo_imei)
297 {
298 	size_t out_len;
299 
300 	out_len = net_buf_linearize(modem.minfo.mdm_imei, sizeof(modem.minfo.mdm_imei) - 1,
301 				    data->rx_buf, 0, len);
302 	modem.minfo.mdm_imei[out_len] = '\0';
303 	LOG_INF("IMEI: %s", modem.minfo.mdm_imei);
304 
305 	return 0;
306 }
307 
308 #if defined(CONFIG_MODEM_SIM_NUMBERS)
309 /* Handler: <IMSI> */
MODEM_CMD_DEFINE(on_cmd_atcmdinfo_imsi)310 MODEM_CMD_DEFINE(on_cmd_atcmdinfo_imsi)
311 {
312 	size_t out_len;
313 
314 	out_len = net_buf_linearize(modem.minfo.mdm_imsi, sizeof(modem.minfo.mdm_imsi) - 1,
315 				    data->rx_buf, 0, len);
316 	modem.minfo.mdm_imsi[out_len] = '\0';
317 	LOG_INF("IMSI: %s", modem.minfo.mdm_imsi);
318 
319 	return 0;
320 }
321 
322 /* Handler: <ICCID> */
MODEM_CMD_DEFINE(on_cmd_atcmdinfo_iccid)323 MODEM_CMD_DEFINE(on_cmd_atcmdinfo_iccid)
324 {
325 	size_t out_len;
326 
327 	out_len = net_buf_linearize(modem.minfo.mdm_iccid, sizeof(modem.minfo.mdm_iccid) - 1,
328 				    data->rx_buf, 0, len);
329 	modem.minfo.mdm_iccid[out_len] = '\0';
330 	if (modem.minfo.mdm_iccid[0] == '+') {
331 		/* Seen on U-blox SARA: "+CCID: nnnnnnnnnnnnnnnnnnnn".
332 		 * Skip over the +CCID bit, which other modems omit.
333 		 */
334 		char *p = strchr(modem.minfo.mdm_iccid, ' ');
335 
336 		if (p) {
337 			size_t iccid_len = strlen(p+1);
338 
339 			(void)memmove(modem.minfo.mdm_iccid, p+1, iccid_len+1);
340 		}
341 	}
342 	LOG_INF("ICCID: %s", modem.minfo.mdm_iccid);
343 
344 	return 0;
345 }
346 #endif /* CONFIG_MODEM_SIM_NUMBERS */
347 
MODEM_CMD_DEFINE(on_cmd_net_reg_sts)348 MODEM_CMD_DEFINE(on_cmd_net_reg_sts)
349 {
350 	modem.net_state = (enum network_state)atoi(argv[1]);
351 
352 	switch (modem.net_state) {
353 	case GSM_NET_NOT_REGISTERED:
354 		LOG_DBG("Network %s.", "not registered");
355 		break;
356 	case GSM_NET_HOME_NETWORK:
357 		LOG_DBG("Network %s.", "registered, home network");
358 		break;
359 	case GSM_NET_SEARCHING:
360 		LOG_DBG("Searching for network...");
361 		break;
362 	case GSM_NET_REGISTRATION_DENIED:
363 		LOG_DBG("Network %s.", "registration denied");
364 		break;
365 	case GSM_NET_UNKNOWN:
366 		LOG_DBG("Network %s.", "unknown");
367 		break;
368 	case GSM_NET_ROAMING:
369 		LOG_DBG("Network %s.", "registered, roaming");
370 		break;
371 	default:
372 		break;
373 	}
374 
375 	return 0;
376 }
377 
378 #if defined(CONFIG_MODEM_CELL_INFO)
379 
380 /*
381  * Handler: +CEREG: <n>[0],<stat>[1],<tac>[2],<ci>[3],<AcT>[4]
382  */
MODEM_CMD_DEFINE(on_cmd_atcmdinfo_cereg)383 MODEM_CMD_DEFINE(on_cmd_atcmdinfo_cereg)
384 {
385 	if (argc >= 4) {
386 		modem.context.data_lac = unquoted_atoi(argv[2], 16);
387 		modem.context.data_cellid = unquoted_atoi(argv[3], 16);
388 		LOG_INF("lac: %u, cellid: %u",
389 			modem.context.data_lac,
390 			modem.context.data_cellid);
391 	}
392 
393 	if (argc >= 5) {
394 		modem.context.data_act = unquoted_atoi(argv[4], 10);
395 		LOG_INF("act: %u", modem.context.data_act);
396 	}
397 
398 	return 0;
399 }
400 
401 static const struct setup_cmd query_cellinfo_cmds[] = {
402 	SETUP_CMD_NOHANDLE("AT+CEREG=2"),
403 	SETUP_CMD("AT+CEREG?", "", on_cmd_atcmdinfo_cereg, 5U, ","),
404 	SETUP_CMD_NOHANDLE("AT+COPS=3,2"),
405 	SETUP_CMD("AT+COPS?", "", on_cmd_atcmdinfo_cops, 3U, ","),
406 };
407 
gsm_query_cellinfo(struct gsm_modem * gsm)408 static int gsm_query_cellinfo(struct gsm_modem *gsm)
409 {
410 	int ret;
411 
412 	ret = modem_cmd_handler_setup_cmds_nolock(&gsm->context.iface,
413 						  &gsm->context.cmd_handler,
414 						  query_cellinfo_cmds,
415 						  ARRAY_SIZE(query_cellinfo_cmds),
416 						  &gsm->sem_response,
417 						  GSM_CMD_SETUP_TIMEOUT);
418 	if (ret < 0) {
419 		LOG_WRN("modem query for cell info returned %d", ret);
420 	}
421 
422 	return ret;
423 }
424 #endif /* CONFIG_MODEM_CELL_INFO */
425 
426 #if defined(CONFIG_MODEM_GSM_ENABLE_CESQ_RSSI)
427 /*
428  * Handler: +CESQ: <rxlev>[0],<ber>[1],<rscp>[2],<ecn0>[3],<rsrq>[4],<rsrp>[5]
429  */
MODEM_CMD_DEFINE(on_cmd_atcmdinfo_rssi_cesq)430 MODEM_CMD_DEFINE(on_cmd_atcmdinfo_rssi_cesq)
431 {
432 	int rsrp, rscp, rxlev;
433 
434 	rsrp = ATOI(argv[5], 0, "rsrp");
435 	rscp = ATOI(argv[2], 0, "rscp");
436 	rxlev = ATOI(argv[0], 0, "rxlev");
437 
438 	if ((rsrp >= 0) && (rsrp <= 97)) {
439 		modem.minfo.mdm_rssi = -140 + (rsrp - 1);
440 		LOG_DBG("RSRP: %d", modem.minfo.mdm_rssi);
441 	} else if ((rscp >= 0) && (rscp <= 96)) {
442 		modem.minfo.mdm_rssi = -120 + (rscp - 1);
443 		LOG_DBG("RSCP: %d", modem.minfo.mdm_rssi);
444 	} else if ((rxlev >= 0) && (rxlev <= 63)) {
445 		modem.minfo.mdm_rssi = -110 + (rxlev - 1);
446 		LOG_DBG("RSSI: %d", modem.minfo.mdm_rssi);
447 	} else {
448 		modem.minfo.mdm_rssi = GSM_RSSI_INVALID;
449 		LOG_DBG("RSRP/RSCP/RSSI not known");
450 	}
451 
452 	return 0;
453 }
454 #else
455 /* Handler: +CSQ: <signal_power>[0],<qual>[1] */
MODEM_CMD_DEFINE(on_cmd_atcmdinfo_rssi_csq)456 MODEM_CMD_DEFINE(on_cmd_atcmdinfo_rssi_csq)
457 {
458 	/* Expected response is "+CSQ: <signal_power>,<qual>" */
459 	if (argc > 0) {
460 		int rssi = atoi(argv[0]);
461 
462 		if ((rssi >= 0) && (rssi <= 31)) {
463 			rssi = -113 + (rssi * 2);
464 		} else {
465 			rssi = GSM_RSSI_INVALID;
466 		}
467 
468 		modem.minfo.mdm_rssi = rssi;
469 		LOG_DBG("RSSI: %d", rssi);
470 	}
471 
472 	return 0;
473 }
474 #endif
475 
476 #if defined(CONFIG_MODEM_GSM_ENABLE_CESQ_RSSI)
477 static const struct modem_cmd read_rssi_cmd =
478 	MODEM_CMD("+CESQ:", on_cmd_atcmdinfo_rssi_cesq, 6U, ",");
479 #else
480 static const struct modem_cmd read_rssi_cmd =
481 	MODEM_CMD("+CSQ:", on_cmd_atcmdinfo_rssi_csq, 2U, ",");
482 #endif
483 
484 static const struct setup_cmd setup_modem_info_cmds[] = {
485 	/* query modem info */
486 	SETUP_CMD("AT+CGMI", "", on_cmd_atcmdinfo_manufacturer, 0U, ""),
487 	SETUP_CMD("AT+CGMM", "", on_cmd_atcmdinfo_model, 0U, ""),
488 	SETUP_CMD("AT+CGMR", "", on_cmd_atcmdinfo_revision, 0U, ""),
489 	SETUP_CMD("AT+CGSN", "", on_cmd_atcmdinfo_imei, 0U, ""),
490 #if defined(CONFIG_MODEM_SIM_NUMBERS)
491 	SETUP_CMD("AT+CIMI", "", on_cmd_atcmdinfo_imsi, 0U, ""),
492 	SETUP_CMD("AT+CCID", "", on_cmd_atcmdinfo_iccid, 0U, ""),
493 #endif
494 };
495 
496 static const struct setup_cmd setup_cmds[] = {
497 	/* no echo */
498 	SETUP_CMD_NOHANDLE("ATE0"),
499 	/* hang up */
500 	SETUP_CMD_NOHANDLE("ATH"),
501 	/* extended errors in numeric form */
502 	SETUP_CMD_NOHANDLE("AT+CMEE=1"),
503 	/* disable unsolicited network registration codes */
504 	SETUP_CMD_NOHANDLE("AT+CREG=0"),
505 	/* create PDP context */
506 	SETUP_CMD_NOHANDLE("AT+CGDCONT=1,\"IP\",\"" CONFIG_MODEM_GSM_APN "\""),
507 #if IS_ENABLED(DT_PROP(GSM_UART_NODE, hw_flow_control))
508 	/* enable hardware flow control */
509 	SETUP_CMD_NOHANDLE("AT+IFC=2,2"),
510 #endif
511 };
512 
MODEM_CMD_DEFINE(on_cmd_atcmdinfo_attached)513 MODEM_CMD_DEFINE(on_cmd_atcmdinfo_attached)
514 {
515 	/* Expected response is "+CGATT: 0|1" so simply look for '1' */
516 	if ((argc > 0) && (atoi(argv[0]) == 1)) {
517 		LOG_INF("Attached to packet service!");
518 	}
519 
520 	return 0;
521 }
522 
523 
524 static const struct modem_cmd read_cops_cmd =
525 	MODEM_CMD_ARGS_MAX("+COPS:", on_cmd_atcmdinfo_cops, 1U, 4U, ",");
526 
527 static const struct modem_cmd check_net_reg_cmd =
528 	MODEM_CMD("+CREG: ", on_cmd_net_reg_sts, 2U, ",");
529 
530 static const struct modem_cmd check_attached_cmd =
531 	MODEM_CMD("+CGATT:", on_cmd_atcmdinfo_attached, 1U, ",");
532 
533 static const struct setup_cmd connect_cmds[] = {
534 	/* connect to network */
535 	SETUP_CMD_NOHANDLE("ATD*99#"),
536 };
537 
gsm_query_modem_info(struct gsm_modem * gsm)538 static int gsm_query_modem_info(struct gsm_modem *gsm)
539 {
540 	int ret;
541 
542 	if (gsm->modem_info_queried) {
543 		return 0;
544 	}
545 
546 	ret = modem_cmd_handler_setup_cmds_nolock(&gsm->context.iface,
547 						  &gsm->context.cmd_handler,
548 						  setup_modem_info_cmds,
549 						  ARRAY_SIZE(setup_modem_info_cmds),
550 						  &gsm->sem_response,
551 						  GSM_CMD_SETUP_TIMEOUT);
552 
553 	if (ret < 0) {
554 		return ret;
555 	}
556 
557 	gsm->modem_info_queried = true;
558 
559 	return 0;
560 }
561 
gsm_setup_mccmno(struct gsm_modem * gsm)562 static int gsm_setup_mccmno(struct gsm_modem *gsm)
563 {
564 	int ret = 0;
565 
566 	if (CONFIG_MODEM_GSM_MANUAL_MCCMNO[0] != '\0') {
567 		/* use manual MCC/MNO entry */
568 		ret = modem_cmd_send_nolock(&gsm->context.iface,
569 					    &gsm->context.cmd_handler,
570 					    NULL, 0,
571 					    "AT+COPS=1,2,\""
572 					    CONFIG_MODEM_GSM_MANUAL_MCCMNO
573 					    "\"",
574 					    &gsm->sem_response,
575 					    GSM_CMD_AT_TIMEOUT);
576 	} else {
577 
578 /* First AT+COPS? is sent to check if automatic selection for operator
579  * is already enabled, if yes we do not send the command AT+COPS= 0,0.
580  */
581 
582 		ret = modem_cmd_send_nolock(&gsm->context.iface,
583 					    &gsm->context.cmd_handler,
584 					    &read_cops_cmd,
585 					    1, "AT+COPS?",
586 					    &gsm->sem_response,
587 					    GSM_CMD_SETUP_TIMEOUT);
588 
589 		if (ret < 0) {
590 			return ret;
591 		}
592 
593 		if (!gsm->context.is_automatic_oper) {
594 			/* register operator automatically */
595 			ret = modem_cmd_send_nolock(&gsm->context.iface,
596 						    &gsm->context.cmd_handler,
597 						    NULL, 0, "AT+COPS=0,0",
598 						    &gsm->sem_response,
599 						    GSM_CMD_AT_TIMEOUT);
600 		}
601 	}
602 
603 	if (ret < 0) {
604 		LOG_ERR("AT+COPS ret:%d", ret);
605 	}
606 
607 	return ret;
608 }
609 
ppp_net_if(void)610 static struct net_if *ppp_net_if(void)
611 {
612 	return net_if_get_first_by_type(&NET_L2_GET_NAME(PPP));
613 }
614 
set_ppp_carrier_on(struct gsm_modem * gsm)615 static void set_ppp_carrier_on(struct gsm_modem *gsm)
616 {
617 	const struct device *ppp_dev = device_get_binding(CONFIG_NET_PPP_DRV_NAME);
618 	struct net_if *iface = gsm->iface;
619 
620 	if (ppp_dev == NULL) {
621 		LOG_ERR("Cannot find PPP %s!", CONFIG_NET_PPP_DRV_NAME);
622 		return;
623 	}
624 
625 	net_if_up(iface);
626 }
627 
query_rssi(struct gsm_modem * gsm,bool lock)628 static void query_rssi(struct gsm_modem *gsm, bool lock)
629 {
630 	int ret;
631 
632 #if defined(CONFIG_MODEM_GSM_ENABLE_CESQ_RSSI)
633 	ret = modem_cmd_send_ext(&gsm->context.iface, &gsm->context.cmd_handler, &read_rssi_cmd, 1,
634 				 "AT+CESQ", &gsm->sem_response, GSM_CMD_SETUP_TIMEOUT,
635 				 lock ? 0 : MODEM_NO_TX_LOCK);
636 #else
637 	ret = modem_cmd_send_ext(&gsm->context.iface, &gsm->context.cmd_handler, &read_rssi_cmd, 1,
638 				 "AT+CSQ", &gsm->sem_response, GSM_CMD_SETUP_TIMEOUT,
639 				 lock ? 0 : MODEM_NO_TX_LOCK);
640 #endif
641 
642 	if (ret < 0) {
643 		LOG_DBG("No answer to RSSI readout, %s", "ignoring...");
644 	}
645 }
646 
query_rssi_lock(struct gsm_modem * gsm)647 static inline void query_rssi_lock(struct gsm_modem *gsm)
648 {
649 	query_rssi(gsm, true);
650 }
651 
query_rssi_nolock(struct gsm_modem * gsm)652 static inline void query_rssi_nolock(struct gsm_modem *gsm)
653 {
654 	query_rssi(gsm, false);
655 }
656 
rssi_handler(struct k_work * work)657 static void rssi_handler(struct k_work *work)
658 {
659 	struct k_work_delayable *dwork = k_work_delayable_from_work(work);
660 	struct gsm_modem *gsm = CONTAINER_OF(dwork, struct gsm_modem, rssi_work_handle);
661 
662 	gsm_ppp_lock(gsm);
663 	query_rssi_lock(gsm);
664 
665 #if defined(CONFIG_MODEM_CELL_INFO)
666 	(void)gsm_query_cellinfo(gsm);
667 #endif
668 	(void)gsm_work_reschedule(&gsm->rssi_work_handle,
669 				  K_SECONDS(CONFIG_MODEM_GSM_RSSI_POLLING_PERIOD));
670 	gsm_ppp_unlock(gsm);
671 }
672 
gsm_finalize_connection(struct k_work * work)673 static void gsm_finalize_connection(struct k_work *work)
674 {
675 	int ret = 0;
676 	struct k_work_delayable *dwork = k_work_delayable_from_work(work);
677 	struct gsm_modem *gsm = CONTAINER_OF(dwork, struct gsm_modem, gsm_configure_work);
678 
679 	gsm_ppp_lock(gsm);
680 
681 	/* If already attached, jump right to RSSI readout */
682 	if (gsm->state == GSM_PPP_ATTACHED) {
683 		goto attached;
684 	}
685 
686 	/* If attach check failed, we should not redo every setup step */
687 	if (gsm->state == GSM_PPP_ATTACHING) {
688 		goto attaching;
689 	}
690 
691 	/* If modem is searching for network, we should skip the setup step */
692 	if (gsm->state == GSM_PPP_REGISTERING) {
693 		goto registering;
694 	}
695 
696 	if (IS_ENABLED(CONFIG_GSM_MUX)) {
697 		ret = modem_cmd_send_nolock(&gsm->context.iface,
698 					    &gsm->context.cmd_handler,
699 					    &response_cmds[0],
700 					    ARRAY_SIZE(response_cmds),
701 					    "AT", &gsm->sem_response,
702 					    GSM_CMD_AT_TIMEOUT);
703 		if (ret < 0) {
704 			LOG_ERR("%s returned %d, %s", "AT", ret, "retrying...");
705 			(void)gsm_work_reschedule(&gsm->gsm_configure_work, GSM_RETRY_DELAY);
706 			goto unlock;
707 		}
708 	}
709 	gsm->state = GSM_PPP_SETUP;
710 
711 	if (IS_ENABLED(CONFIG_MODEM_GSM_FACTORY_RESET_AT_BOOT)) {
712 		(void)modem_cmd_send_nolock(&gsm->context.iface,
713 					    &gsm->context.cmd_handler,
714 					    &response_cmds[0],
715 					    ARRAY_SIZE(response_cmds),
716 					    "AT&F", &gsm->sem_response,
717 					    GSM_CMD_AT_TIMEOUT);
718 		(void)k_sleep(K_SECONDS(1));
719 	}
720 
721 	ret = gsm_setup_mccmno(gsm);
722 	if (ret < 0) {
723 		LOG_ERR("%s returned %d, %s", "gsm_setup_mccmno", ret, "retrying...");
724 
725 		(void)gsm_work_reschedule(&gsm->gsm_configure_work, GSM_RETRY_DELAY);
726 		goto unlock;
727 	}
728 
729 	ret = modem_cmd_handler_setup_cmds_nolock(&gsm->context.iface,
730 						  &gsm->context.cmd_handler,
731 						  setup_cmds,
732 						  ARRAY_SIZE(setup_cmds),
733 						  &gsm->sem_response,
734 						  GSM_CMD_SETUP_TIMEOUT);
735 	if (ret < 0) {
736 		LOG_DBG("%s returned %d, %s", "setup_cmds", ret, "retrying...");
737 		(void)gsm_work_reschedule(&gsm->gsm_configure_work, GSM_RETRY_DELAY);
738 		goto unlock;
739 	}
740 
741 	ret = gsm_query_modem_info(gsm);
742 	if (ret < 0) {
743 		LOG_DBG("Unable to query modem information %d", ret);
744 		(void)gsm_work_reschedule(&gsm->gsm_configure_work, GSM_RETRY_DELAY);
745 		goto unlock;
746 	}
747 
748 	gsm->state = GSM_PPP_REGISTERING;
749 registering:
750 	/* Wait for cell tower registration */
751 	ret = modem_cmd_send_nolock(&gsm->context.iface,
752 				    &gsm->context.cmd_handler,
753 				    &check_net_reg_cmd, 1,
754 				    "AT+CREG?",
755 				    &gsm->sem_response,
756 				    GSM_CMD_SETUP_TIMEOUT);
757 	if ((ret < 0) || ((gsm->net_state != GSM_NET_ROAMING) &&
758 			 (gsm->net_state != GSM_NET_HOME_NETWORK))) {
759 		if (gsm->retries == 0) {
760 			gsm->retries = CONFIG_MODEM_GSM_REGISTER_TIMEOUT *
761 				(MSEC_PER_SEC / GSM_REGISTER_DELAY_MSEC);
762 		} else {
763 			gsm->retries--;
764 		}
765 
766 		(void)gsm_work_reschedule(&gsm->gsm_configure_work,
767 					  K_MSEC(GSM_REGISTER_DELAY_MSEC));
768 		goto unlock;
769 	}
770 
771 	gsm->retries = 0;
772 	gsm->state = GSM_PPP_ATTACHING;
773 attaching:
774 	/* Don't initialize PPP until we're attached to packet service */
775 	ret = modem_cmd_send_nolock(&gsm->context.iface,
776 				    &gsm->context.cmd_handler,
777 				    &check_attached_cmd, 1,
778 				    "AT+CGATT?",
779 				    &gsm->sem_response,
780 				    GSM_CMD_SETUP_TIMEOUT);
781 	if (ret < 0) {
782 		/*
783 		 * retries not set        -> trigger N attach retries
784 		 * retries set            -> decrement and retry
785 		 * retries set, becomes 0 -> trigger full retry
786 		 */
787 		if (gsm->retries == 0) {
788 			gsm->retries = CONFIG_MODEM_GSM_ATTACH_TIMEOUT *
789 				(MSEC_PER_SEC / GSM_ATTACH_RETRY_DELAY_MSEC);
790 		} else {
791 			gsm->retries--;
792 		}
793 
794 		LOG_DBG("Not attached, %s", "retrying...");
795 
796 		(void)gsm_work_reschedule(&gsm->gsm_configure_work,
797 					K_MSEC(GSM_ATTACH_RETRY_DELAY_MSEC));
798 		goto unlock;
799 	}
800 
801 	/* Attached, clear retry counter */
802 	LOG_DBG("modem attach returned %d, %s", ret, "read RSSI");
803 	gsm->state = GSM_PPP_ATTACHED;
804 	gsm->retries = GSM_RSSI_RETRIES;
805 
806  attached:
807 
808 	if (!IS_ENABLED(CONFIG_GSM_MUX)) {
809 		/* Read connection quality (RSSI) before PPP carrier is ON */
810 		query_rssi_nolock(gsm);
811 
812 		if (!((gsm->minfo.mdm_rssi) && (gsm->minfo.mdm_rssi != GSM_RSSI_INVALID) &&
813 			(gsm->minfo.mdm_rssi < GSM_RSSI_MAXVAL))) {
814 
815 			LOG_DBG("Not valid RSSI, %s", "retrying...");
816 			if (gsm->retries-- > 0) {
817 				(void)gsm_work_reschedule(&gsm->gsm_configure_work,
818 							K_MSEC(GSM_RSSI_RETRY_DELAY_MSEC));
819 				goto unlock;
820 			}
821 		}
822 #if defined(CONFIG_MODEM_CELL_INFO)
823 		(void)gsm_query_cellinfo(gsm);
824 #endif
825 	}
826 
827 	LOG_DBG("modem RSSI: %d, %s", gsm->minfo.mdm_rssi, "enable PPP");
828 
829 	ret = modem_cmd_handler_setup_cmds_nolock(&gsm->context.iface,
830 						  &gsm->context.cmd_handler,
831 						  connect_cmds,
832 						  ARRAY_SIZE(connect_cmds),
833 						  &gsm->sem_response,
834 						  GSM_CMD_SETUP_TIMEOUT);
835 	if (ret < 0) {
836 		LOG_DBG("%s returned %d, %s", "connect_cmds", ret, "retrying...");
837 		(void)gsm_work_reschedule(&gsm->gsm_configure_work, GSM_RETRY_DELAY);
838 		goto unlock;
839 	}
840 
841 	gsm->state = GSM_PPP_SETUP_DONE;
842 	set_ppp_carrier_on(gsm);
843 
844 	if (IS_ENABLED(CONFIG_GSM_MUX)) {
845 		/* Re-use the original iface for AT channel */
846 		ret = modem_iface_uart_init_dev(&gsm->context.iface,
847 						gsm->at_dev);
848 		if (ret < 0) {
849 			LOG_DBG("iface %suart error %d", "AT ", ret);
850 			gsm->state = GSM_PPP_STATE_ERROR;
851 		} else {
852 			/* Do a test and try to send AT command to modem */
853 			ret = modem_cmd_send_nolock(
854 				&gsm->context.iface,
855 				&gsm->context.cmd_handler,
856 				&response_cmds[0],
857 				ARRAY_SIZE(response_cmds),
858 				"AT", &gsm->sem_response,
859 				GSM_CMD_AT_TIMEOUT);
860 			if (ret < 0) {
861 				LOG_WRN("%s returned %d, %s", "AT", ret, "iface failed");
862 				gsm->state = GSM_PPP_STATE_ERROR;
863 			} else {
864 				LOG_INF("AT channel %d connected to %s",
865 					DLCI_AT, gsm->at_dev->name);
866 			}
867 		}
868 
869 		modem_cmd_handler_tx_unlock(&gsm->context.cmd_handler);
870 		if (gsm->state != GSM_PPP_STATE_ERROR) {
871 			(void)gsm_work_reschedule(&gsm->rssi_work_handle,
872 						K_SECONDS(CONFIG_MODEM_GSM_RSSI_POLLING_PERIOD));
873 		}
874 	}
875 
876 unlock:
877 	gsm_ppp_unlock(gsm);
878 }
879 
mux_enable(struct gsm_modem * gsm)880 static int mux_enable(struct gsm_modem *gsm)
881 {
882 	int ret;
883 
884 	/* Turn on muxing */
885 	if (IS_ENABLED(CONFIG_MODEM_GSM_SIMCOM)) {
886 		ret = modem_cmd_send_nolock(
887 			&gsm->context.iface,
888 			&gsm->context.cmd_handler,
889 			&response_cmds[0],
890 			ARRAY_SIZE(response_cmds),
891 #if defined(SIMCOM_LTE)
892 			/* FIXME */
893 			/* Some SIMCOM modems can set the channels */
894 			/* Control channel always at DLCI 0 */
895 			"AT+CMUXSRVPORT=0,0;"
896 			/* PPP should be at DLCI 1 */
897 			"+CMUXSRVPORT=" STRINGIFY(DLCI_PPP) ",1;"
898 			/* AT should be at DLCI 2 */
899 			"+CMUXSRVPORT=" STRINGIFY(DLCI_AT) ",1;"
900 #else
901 			"AT"
902 #endif
903 			"+CMUX=0,0,5,"
904 			STRINGIFY(CONFIG_GSM_MUX_MRU_DEFAULT_LEN),
905 			&gsm->sem_response,
906 			GSM_CMD_AT_TIMEOUT);
907 	} else if (IS_ENABLED(CONFIG_MODEM_GSM_QUECTEL)) {
908 		ret = modem_cmd_send_nolock(&gsm->context.iface,
909 				    &gsm->context.cmd_handler,
910 				    &response_cmds[0],
911 				    ARRAY_SIZE(response_cmds),
912 				    "AT+CMUX=0,0,5,"
913 				    STRINGIFY(CONFIG_GSM_MUX_MRU_DEFAULT_LEN),
914 				    &gsm->sem_response,
915 				    GSM_CMD_AT_TIMEOUT);
916 
917 		/* Arbitrary delay for Quectel modems to initialize the CMUX,
918 		 * without this the AT cmd will fail.
919 		 */
920 		(void)k_sleep(K_SECONDS(1));
921 	} else {
922 		/* Generic GSM modem */
923 		ret = modem_cmd_send_nolock(&gsm->context.iface,
924 				     &gsm->context.cmd_handler,
925 				     &response_cmds[0],
926 				     ARRAY_SIZE(response_cmds),
927 				     "AT+CMUX=0", &gsm->sem_response,
928 				     GSM_CMD_AT_TIMEOUT);
929 	}
930 
931 	if (ret < 0) {
932 		LOG_ERR("AT+CMUX ret:%d", ret);
933 	}
934 
935 	return ret;
936 }
937 
mux_setup_next(struct gsm_modem * gsm)938 static void mux_setup_next(struct gsm_modem *gsm)
939 {
940 	(void)gsm_work_reschedule(&gsm->gsm_configure_work, K_MSEC(1));
941 }
942 
mux_attach_cb(const struct device * mux,int dlci_address,bool connected,void * user_data)943 static void mux_attach_cb(const struct device *mux, int dlci_address,
944 			  bool connected, void *user_data)
945 {
946 	LOG_DBG("DLCI %d to %s %s", dlci_address, mux->name,
947 		connected ? "connected" : "disconnected");
948 
949 	if (connected) {
950 		uart_irq_rx_enable(mux);
951 		uart_irq_tx_enable(mux);
952 	}
953 
954 	mux_setup_next(user_data);
955 }
956 
mux_attach(const struct device * mux,const struct device * uart,int dlci_address,void * user_data)957 static int mux_attach(const struct device *mux, const struct device *uart,
958 		      int dlci_address, void *user_data)
959 {
960 	int ret = uart_mux_attach(mux, uart, dlci_address, mux_attach_cb,
961 				  user_data);
962 	if (ret < 0) {
963 		LOG_ERR("Cannot attach DLCI %d (%s) to %s (%d)", dlci_address,
964 			mux->name, uart->name, ret);
965 		return ret;
966 	}
967 
968 	return 0;
969 }
970 
mux_setup(struct k_work * work)971 static void mux_setup(struct k_work *work)
972 {
973 	struct k_work_delayable *dwork = k_work_delayable_from_work(work);
974 	struct gsm_modem *gsm = CONTAINER_OF(dwork, struct gsm_modem,
975 					     gsm_configure_work);
976 	const struct device *const uart = DEVICE_DT_GET(GSM_UART_NODE);
977 	int ret;
978 
979 	gsm_ppp_lock(gsm);
980 
981 	switch (gsm->state) {
982 	case GSM_PPP_STATE_CONTROL_CHANNEL:
983 		/* We need to call this to reactivate mux ISR. Note: This is only called
984 		 * after re-initing gsm_ppp.
985 		 */
986 		if (gsm->ppp_dev != NULL) {
987 			uart_mux_enable(gsm->ppp_dev);
988 		}
989 
990 		/* Get UART device. There is one dev / DLCI */
991 		if (gsm->control_dev == NULL) {
992 			gsm->control_dev = uart_mux_alloc();
993 			if (gsm->control_dev == NULL) {
994 				LOG_DBG("Cannot get UART mux for %s channel",
995 					"control");
996 				goto fail;
997 			}
998 		}
999 
1000 		ret = mux_attach(gsm->control_dev, uart, DLCI_CONTROL, gsm);
1001 		if (ret < 0) {
1002 			goto fail;
1003 		}
1004 
1005 		gsm->state = GSM_PPP_STATE_PPP_CHANNEL;
1006 		goto unlock;
1007 
1008 	case GSM_PPP_STATE_PPP_CHANNEL:
1009 		if (gsm->ppp_dev == NULL) {
1010 			gsm->ppp_dev = uart_mux_alloc();
1011 			if (gsm->ppp_dev == NULL) {
1012 				LOG_DBG("Cannot get UART mux for %s channel",
1013 					"PPP");
1014 				goto fail;
1015 			}
1016 		}
1017 
1018 		ret = mux_attach(gsm->ppp_dev, uart, DLCI_PPP, gsm);
1019 		if (ret < 0) {
1020 			goto fail;
1021 		}
1022 
1023 		gsm->state = GSM_PPP_STATE_AT_CHANNEL;
1024 		goto unlock;
1025 
1026 	case GSM_PPP_STATE_AT_CHANNEL:
1027 		if (gsm->at_dev == NULL) {
1028 			gsm->at_dev = uart_mux_alloc();
1029 			if (gsm->at_dev == NULL) {
1030 				LOG_DBG("Cannot get UART mux for %s channel",
1031 					"AT");
1032 				goto fail;
1033 			}
1034 		}
1035 
1036 		ret = mux_attach(gsm->at_dev, uart, DLCI_AT, gsm);
1037 		if (ret < 0) {
1038 			goto fail;
1039 		}
1040 
1041 		gsm->state = GSM_PPP_STATE_DONE;
1042 		goto unlock;
1043 
1044 	case GSM_PPP_STATE_DONE:
1045 		/* At least the SIMCOM modem expects that the Internet
1046 		 * connection is created in PPP channel. We will need
1047 		 * to attach the AT channel to context iface after the
1048 		 * PPP connection is established in order to give AT commands
1049 		 * to the modem.
1050 		 */
1051 		ret = modem_iface_uart_init_dev(&gsm->context.iface,
1052 						gsm->ppp_dev);
1053 		if (ret < 0) {
1054 			LOG_DBG("iface %suart error %d", "PPP ", ret);
1055 			goto fail;
1056 		}
1057 
1058 		LOG_INF("PPP channel %d connected to %s",
1059 			DLCI_PPP, gsm->ppp_dev->name);
1060 
1061 		k_work_init_delayable(&gsm->gsm_configure_work, gsm_finalize_connection);
1062 		(void)gsm_work_reschedule(&gsm->gsm_configure_work, K_NO_WAIT);
1063 		goto unlock;
1064 	default:
1065 		__ASSERT(0, "%s while in state: %d", "mux_setup", gsm->state);
1066 		/* In case CONFIG_ASSERT is off, goto fail */
1067 		goto fail;
1068 	}
1069 
1070 fail:
1071 	gsm->state = GSM_PPP_STATE_ERROR;
1072 unlock:
1073 	gsm_ppp_unlock(gsm);
1074 }
1075 
gsm_configure(struct k_work * work)1076 static void gsm_configure(struct k_work *work)
1077 {
1078 	struct k_work_delayable *dwork = k_work_delayable_from_work(work);
1079 	struct gsm_modem *gsm = CONTAINER_OF(dwork, struct gsm_modem,
1080 					     gsm_configure_work);
1081 	int ret = -1;
1082 
1083 	gsm_ppp_lock(gsm);
1084 
1085 	if (gsm->state == GSM_PPP_WAIT_AT) {
1086 		goto wait_at;
1087 	}
1088 
1089 	if (gsm->state == GSM_PPP_START) {
1090 		LOG_DBG("Starting modem %p configuration", gsm);
1091 
1092 		if (gsm->modem_on_cb != NULL) {
1093 			gsm->modem_on_cb(gsm->dev, gsm->user_data);
1094 		}
1095 
1096 		gsm->state = GSM_PPP_WAIT_AT;
1097 	}
1098 
1099 wait_at:
1100 	ret = modem_cmd_send_nolock(&gsm->context.iface,
1101 				    &gsm->context.cmd_handler,
1102 				    &response_cmds[0],
1103 				    ARRAY_SIZE(response_cmds),
1104 				    "AT", &gsm->sem_response,
1105 				    GSM_CMD_AT_TIMEOUT);
1106 	if (ret < 0) {
1107 		LOG_DBG("modem not ready %d", ret);
1108 		goto retry;
1109 	}
1110 
1111 	gsm->state = GSM_PPP_AT_RDY;
1112 
1113 	if (IS_ENABLED(CONFIG_GSM_MUX)) {
1114 		if (mux_enable(gsm) == 0) {
1115 			LOG_DBG("GSM muxing %s", "enabled");
1116 		} else {
1117 			LOG_DBG("GSM muxing %s", "disabled");
1118 			goto retry;
1119 		}
1120 
1121 		gsm->state = GSM_PPP_STATE_INIT;
1122 
1123 		k_work_init_delayable(&gsm->gsm_configure_work, mux_setup);
1124 	} else {
1125 		k_work_init_delayable(&gsm->gsm_configure_work, gsm_finalize_connection);
1126 	}
1127 
1128 retry:
1129 	(void)gsm_work_reschedule(&gsm->gsm_configure_work, K_NO_WAIT);
1130 	gsm_ppp_unlock(gsm);
1131 }
1132 
gsm_ppp_start(const struct device * dev)1133 void gsm_ppp_start(const struct device *dev)
1134 {
1135 	int ret;
1136 	struct gsm_modem *gsm = dev->data;
1137 
1138 	gsm_ppp_lock(gsm);
1139 
1140 	if (gsm->state != GSM_PPP_STOP) {
1141 		LOG_ERR("gsm_ppp is already %s", "started");
1142 		goto unlock;
1143 	}
1144 
1145 	gsm->state = GSM_PPP_START;
1146 
1147 	/* Re-init underlying UART comms */
1148 	ret = modem_iface_uart_init_dev(&gsm->context.iface, DEVICE_DT_GET(GSM_UART_NODE));
1149 	if (ret < 0) {
1150 		LOG_ERR("modem_iface_uart_init returned %d", ret);
1151 		gsm->state = GSM_PPP_STATE_ERROR;
1152 		goto unlock;
1153 	}
1154 
1155 	k_work_init_delayable(&gsm->gsm_configure_work, gsm_configure);
1156 	(void)gsm_work_reschedule(&gsm->gsm_configure_work, K_NO_WAIT);
1157 
1158 unlock:
1159 	gsm_ppp_unlock(gsm);
1160 }
1161 
gsm_ppp_stop(const struct device * dev)1162 void gsm_ppp_stop(const struct device *dev)
1163 {
1164 	struct gsm_modem *gsm = dev->data;
1165 	struct net_if *iface = gsm->iface;
1166 	struct k_work_sync work_sync;
1167 
1168 	if (gsm->state == GSM_PPP_STOP) {
1169 		LOG_ERR("gsm_ppp is already %s", "stopped");
1170 		return;
1171 	}
1172 
1173 	(void)k_work_cancel_delayable_sync(&gsm->gsm_configure_work, &work_sync);
1174 	if (IS_ENABLED(CONFIG_GSM_MUX)) {
1175 		(void)k_work_cancel_delayable_sync(&gsm->rssi_work_handle, &work_sync);
1176 	}
1177 
1178 	gsm_ppp_lock(gsm);
1179 
1180 	/* wait for the interface to be properly down */
1181 	if (net_if_is_up(iface)) {
1182 		net_if_down(ppp_net_if());
1183 		(void)k_sem_take(&gsm->sem_if_down, K_FOREVER);
1184 	}
1185 
1186 	if (IS_ENABLED(CONFIG_GSM_MUX)) {
1187 		if (gsm->ppp_dev != NULL) {
1188 			uart_mux_disable(gsm->ppp_dev);
1189 		}
1190 
1191 		if (modem_cmd_handler_tx_lock(&gsm->context.cmd_handler,
1192 								GSM_CMD_LOCK_TIMEOUT) < 0) {
1193 			LOG_WRN("Failed locking modem cmds!");
1194 		}
1195 	}
1196 
1197 	if (gsm->modem_off_cb != NULL) {
1198 		gsm->modem_off_cb(gsm->dev, gsm->user_data);
1199 	}
1200 
1201 	gsm->state = GSM_PPP_STOP;
1202 	gsm->net_state = GSM_NET_INIT;
1203 	gsm_ppp_unlock(gsm);
1204 }
1205 
gsm_ppp_register_modem_power_callback(const struct device * dev,gsm_modem_power_cb modem_on,gsm_modem_power_cb modem_off,void * user_data)1206 void gsm_ppp_register_modem_power_callback(const struct device *dev,
1207 					   gsm_modem_power_cb modem_on,
1208 					   gsm_modem_power_cb modem_off,
1209 					   void *user_data)
1210 {
1211 	struct gsm_modem *gsm = dev->data;
1212 
1213 	gsm_ppp_lock(gsm);
1214 
1215 	gsm->modem_on_cb = modem_on;
1216 	gsm->modem_off_cb = modem_off;
1217 
1218 	gsm->user_data = user_data;
1219 	gsm_ppp_unlock(gsm);
1220 }
1221 
gsm_ppp_modem_info(const struct device * dev)1222 const struct gsm_ppp_modem_info *gsm_ppp_modem_info(const struct device *dev)
1223 {
1224 	struct gsm_modem *gsm = dev->data;
1225 
1226 	return &gsm->minfo;
1227 }
1228 
gsm_mgmt_event_handler(struct net_mgmt_event_callback * cb,uint32_t mgmt_event,struct net_if * iface)1229 static void gsm_mgmt_event_handler(struct net_mgmt_event_callback *cb,
1230 			  uint32_t mgmt_event, struct net_if *iface)
1231 {
1232 	if ((mgmt_event & NET_EVENT_IF_DOWN) != mgmt_event) {
1233 		return;
1234 	}
1235 
1236 	/* Right now we only support 1 GSM instance */
1237 	if (iface != modem.iface) {
1238 		return;
1239 	}
1240 
1241 	if (mgmt_event == NET_EVENT_IF_DOWN) {
1242 		LOG_INF("GSM network interface down");
1243 		/* raise semaphore to indicate the interface is down */
1244 		k_sem_give(&modem.sem_if_down);
1245 		return;
1246 	}
1247 }
1248 
gsm_init(const struct device * dev)1249 static int gsm_init(const struct device *dev)
1250 {
1251 	struct gsm_modem *gsm = dev->data;
1252 	int ret;
1253 
1254 	LOG_DBG("Generic GSM modem (%p)", gsm);
1255 
1256 	(void)k_mutex_init(&gsm->lock);
1257 	gsm->dev = dev;
1258 
1259 	const struct modem_cmd_handler_config cmd_handler_config = {
1260 		.match_buf = &gsm->cmd_match_buf[0],
1261 		.match_buf_len = sizeof(gsm->cmd_match_buf),
1262 		.buf_pool = &gsm_recv_pool,
1263 		.alloc_timeout = K_NO_WAIT,
1264 		.eol = "\r",
1265 		.user_data = NULL,
1266 		.response_cmds = response_cmds,
1267 		.response_cmds_len = ARRAY_SIZE(response_cmds),
1268 		.unsol_cmds = NULL,
1269 		.unsol_cmds_len = 0,
1270 	};
1271 
1272 	(void)k_sem_init(&gsm->sem_response, 0, 1);
1273 	(void)k_sem_init(&gsm->sem_if_down, 0, 1);
1274 
1275 	ret = modem_cmd_handler_init(&gsm->context.cmd_handler, &gsm->cmd_handler_data,
1276 				     &cmd_handler_config);
1277 	if (ret < 0) {
1278 		LOG_DBG("cmd handler error %d", ret);
1279 		return ret;
1280 	}
1281 
1282 #if defined(CONFIG_MODEM_SHELL)
1283 	/* modem information storage */
1284 	gsm->context.data_manufacturer = gsm->minfo.mdm_manufacturer;
1285 	gsm->context.data_model = gsm->minfo.mdm_model;
1286 	gsm->context.data_revision = gsm->minfo.mdm_revision;
1287 	gsm->context.data_imei = gsm->minfo.mdm_imei;
1288 #if defined(CONFIG_MODEM_SIM_NUMBERS)
1289 	gsm->context.data_imsi = gsm->minfo.mdm_imsi;
1290 	gsm->context.data_iccid = gsm->minfo.mdm_iccid;
1291 #endif	/* CONFIG_MODEM_SIM_NUMBERS */
1292 	gsm->context.data_rssi = &gsm->minfo.mdm_rssi;
1293 #endif	/* CONFIG_MODEM_SHELL */
1294 
1295 	gsm->context.is_automatic_oper = false;
1296 
1297 	const struct modem_iface_uart_config uart_config = {
1298 		.rx_rb_buf = &gsm->gsm_rx_rb_buf[0],
1299 		.rx_rb_buf_len = sizeof(gsm->gsm_rx_rb_buf),
1300 		.hw_flow_control = DT_PROP(GSM_UART_NODE, hw_flow_control),
1301 		.dev = DEVICE_DT_GET(GSM_UART_NODE),
1302 	};
1303 
1304 	ret = modem_iface_uart_init(&gsm->context.iface, &gsm->gsm_data, &uart_config);
1305 	if (ret < 0) {
1306 		LOG_DBG("iface uart error %d", ret);
1307 		return ret;
1308 	}
1309 
1310 	ret = modem_context_register(&gsm->context);
1311 	if (ret < 0) {
1312 		LOG_DBG("context error %d", ret);
1313 		return ret;
1314 	}
1315 
1316 	/* Initialize to stop state so that it can be started later */
1317 	gsm->state = GSM_PPP_STOP;
1318 
1319 	gsm->net_state = GSM_NET_INIT;
1320 
1321 	LOG_DBG("iface->read %p iface->write %p",
1322 		gsm->context.iface.read, gsm->context.iface.write);
1323 
1324 	(void)k_thread_create(&gsm->rx_thread, gsm_rx_stack,
1325 			      K_KERNEL_STACK_SIZEOF(gsm_rx_stack),
1326 			      (k_thread_entry_t) gsm_rx,
1327 			      gsm, NULL, NULL, K_PRIO_COOP(7), 0, K_NO_WAIT);
1328 	(void)k_thread_name_set(&gsm->rx_thread, "gsm_rx");
1329 
1330 	/* initialize the work queue */
1331 	k_work_queue_init(&gsm->workq);
1332 	k_work_queue_start(&gsm->workq, gsm_workq_stack, K_KERNEL_STACK_SIZEOF(gsm_workq_stack),
1333 			   K_PRIO_COOP(7), NULL);
1334 	(void)k_thread_name_set(&gsm->workq.thread, "gsm_workq");
1335 
1336 	if (IS_ENABLED(CONFIG_GSM_MUX)) {
1337 		k_work_init_delayable(&gsm->rssi_work_handle, rssi_handler);
1338 	}
1339 
1340 	gsm->iface = ppp_net_if();
1341 	if (gsm->iface == NULL) {
1342 		LOG_ERR("Couldn't find ppp net_if!");
1343 		return -ENODEV;
1344 	}
1345 
1346 	net_mgmt_init_event_callback(&gsm->gsm_mgmt_cb, gsm_mgmt_event_handler,
1347 				     NET_EVENT_IF_DOWN);
1348 	net_mgmt_add_event_callback(&gsm->gsm_mgmt_cb);
1349 
1350 	if (IS_ENABLED(CONFIG_GSM_PPP_AUTOSTART)) {
1351 		gsm_ppp_start(dev);
1352 	}
1353 
1354 	return 0;
1355 }
1356 
1357 DEVICE_DT_DEFINE(DT_DRV_INST(0), gsm_init, NULL, &modem, NULL,
1358 		 POST_KERNEL, CONFIG_MODEM_GSM_INIT_PRIORITY, NULL);
1359