From ac751b7bcce99d86fa4ab281586be31a35c6619a Mon Sep 17 00:00:00 2001
From: Ryan Erickson <ryan.erickson@lairdconnect.com>
Date: Thu, 19 Aug 2021 15:32:34 -0500
Subject: [PATCH] drivers: modem: hl7800: Query IMSI

Add API to query SIM card IMSI.

Signed-off-by: Ryan Erickson <ryan.erickson@lairdconnect.com>
---
 drivers/modem/hl7800.c         | 47 ++++++++++++++++++++++++++++++++++
 include/drivers/modem/hl7800.h | 10 ++++++++
 2 files changed, 57 insertions(+)

diff --git a/drivers/modem/hl7800.c b/drivers/modem/hl7800.c
index d6fd3f99779..f8826110aee 100644
--- a/drivers/modem/hl7800.c
+++ b/drivers/modem/hl7800.c
@@ -505,6 +505,7 @@ struct hl7800_iface_ctx {
 	enum mdm_hl7800_radio_mode mdm_rat;
 	char mdm_active_bands_string[MDM_HL7800_LTE_BAND_STR_SIZE];
 	char mdm_bands_string[MDM_HL7800_LTE_BAND_STR_SIZE];
+	char mdm_imsi[MDM_HL7800_IMSI_MAX_STR_SIZE];
 	uint16_t mdm_bands_top;
 	uint32_t mdm_bands_middle;
 	uint32_t mdm_bands_bottom;
@@ -1517,6 +1518,42 @@ done:
 	return true;
 }
 
+static bool on_cmd_atcmdinfo_imsi(struct net_buf **buf, uint16_t len)
+{
+	struct net_buf *frag = NULL;
+	size_t out_len;
+
+	/* The handler for the IMSI is based on the command.
+	 *  waiting for: <IMSI>\r\n
+	 */
+	wait_for_modem_data_and_newline(buf, net_buf_frags_len(*buf),
+					MDM_HL7800_IMSI_MIN_STR_SIZE);
+
+	frag = NULL;
+	len = net_buf_findcrlf(*buf, &frag);
+	if (!frag) {
+		LOG_ERR("Unable to find IMSI end");
+		goto done;
+	}
+	if (len > MDM_HL7800_IMSI_MAX_STRLEN) {
+		LOG_WRN("IMSI too long (len:%d)", len);
+		len = MDM_HL7800_IMSI_MAX_STRLEN;
+	}
+
+	out_len = net_buf_linearize(ictx.mdm_imsi, MDM_HL7800_IMSI_MAX_STR_SIZE,
+				    *buf, 0, len);
+	ictx.mdm_imsi[out_len] = 0;
+
+	if (strstr(ictx.mdm_imsi, "ERROR") != NULL) {
+		LOG_ERR("Unable to read IMSI");
+		memset(ictx.mdm_imsi, 0, sizeof(ictx.mdm_imsi));
+	}
+
+	LOG_INF("IMSI: %s", log_strdup(ictx.mdm_imsi));
+done:
+	return true;
+}
+
 static void dns_work_cb(struct k_work *work)
 {
 #if defined(CONFIG_DNS_RESOLVER) && !defined(CONFIG_DNS_SERVER_IP_ADDRESSES)
@@ -1556,6 +1593,11 @@ char *mdm_hl7800_get_fw_version(void)
 	return ictx.mdm_revision;
 }
 
+char *mdm_hl7800_get_imsi(void)
+{
+	return ictx.mdm_imsi;
+}
+
 /* Handler: +CGCONTRDP: <cid>,<bearer_id>,<apn>,<local_addr and subnet_mask>,
  *			<gw_addr>,<DNS_prim_addr>,<DNS_sec_addr>
  */
@@ -3382,6 +3424,7 @@ static void hl7800_rx(void)
 		CMD_HANDLER("+CGDCONT: 1", atcmdinfo_pdp_context),
 		CMD_HANDLER("AT+CEREG?", network_report_query),
 		CMD_HANDLER("+KCARRIERCFG: ", operator_index_query),
+		CMD_HANDLER("AT+CIMI", atcmdinfo_imsi),
 #ifdef CONFIG_NEWLIB_LIBC
 		CMD_HANDLER("+CCLK: ", rtc_query),
 #endif
@@ -4079,6 +4122,10 @@ reboot:
 	/* query SIM ICCID */
 	SEND_AT_CMD_IGNORE_ERROR("AT+CCID?");
 
+	/* query SIM IMSI */
+	(void)send_at_cmd(NULL, "AT+CIMI", MDM_CMD_SEND_TIMEOUT,
+			  MDM_DEFAULT_AT_CMD_RETRIES, true);
+
 	/* An empty string is used here so that it doesn't conflict
 	 * with the APN used in the +CGDCONT command.
 	 */
diff --git a/include/drivers/modem/hl7800.h b/include/drivers/modem/hl7800.h
index c6cd6e13836..a1899947f7a 100644
--- a/include/drivers/modem/hl7800.h
+++ b/include/drivers/modem/hl7800.h
@@ -60,6 +60,10 @@ struct mdm_hl7800_apn {
 #define MDM_HL7800_OPERATOR_INDEX_SIZE 3
 #define MDM_HL7800_OPERATOR_INDEX_STRLEN (MDM_HL7800_OPERATOR_INDEX_SIZE - 1)
 
+#define MDM_HL7800_IMSI_MIN_STR_SIZE 15
+#define MDM_HL7800_IMSI_MAX_STR_SIZE 16
+#define MDM_HL7800_IMSI_MAX_STRLEN (MDM_HL7800_IMSI_MAX_STR_SIZE - 1)
+
 enum mdm_hl7800_radio_mode { MDM_RAT_CAT_M1 = 0, MDM_RAT_CAT_NB1 };
 
 enum mdm_hl7800_event {
@@ -208,6 +212,12 @@ char *mdm_hl7800_get_imei(void);
  */
 char *mdm_hl7800_get_fw_version(void);
 
+/**
+ * @brief Get the IMSI
+ *
+ */
+char *mdm_hl7800_get_imsi(void);
+
 /**
  * @brief Update the Access Point Name in the modem.
  *