Setup GSM 07.10 multiplexing using the kernel n_gsm line discpline
driver, and use the virtual tty devices as Aux and Modem channels.
The driver supports rts/cts on the underlying serial device. This is
enabled with OFONO_QUECTED_RTSCTS udev environment, e.g.:
KERNEL=="ttymxc0", ENV{OFONO_DRIVER}="quectel", \
ENV{OFONO_QUECTEL_RTSCTS}="on"
---
Changes since v1:
* work around kernel dead-lock in n_gsm tty line discipline
* clearify explanatory comment in cfun_query()
* add error handling to cfun_query()
* move hard-coding of gsm tty paths from udevng to quectel
plugins/quectel.c | 275 ++++++++++++++++++++++++++++++++++++++++------
plugins/udevng.c | 24 +++-
2 files changed, 267 insertions(+), 32 deletions(-)
diff --git a/plugins/quectel.c b/plugins/quectel.c
index 6e93f45a..8914cf45 100644
--- a/plugins/quectel.c
+++ b/plugins/quectel.c
@@ -25,7 +25,13 @@
#include <errno.h>
#include <stdlib.h>
+#include <stdbool.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#include <sys/ioctl.h>
+#include <linux/tty.h>
+#include <linux/gsmmux.h>
#include <ell/ell.h>
#include <gatchat.h>
#include <gattty.h>
@@ -47,11 +53,28 @@ static const char *cfun_prefix[] = { "+CFUN:", NULL };
static const char *cpin_prefix[] = { "+CPIN:", NULL };
static const char *none_prefix[] = { NULL };
+static const uint8_t gsm0710_terminate[] = {
+ 0xf9, /* open flag */
+ 0x03, /* channel 0 */
+ 0xef, /* UIH frame */
+ 0x05, /* 2 data bytes */
+ 0xc3, /* terminate 1 */
+ 0x01, /* terminate 2 */
+ 0xf2, /* crc */
+ 0xf9, /* close flag */
+};
+
struct quectel_data {
GAtChat *modem;
GAtChat *aux;
guint cpin_ready;
- gboolean have_sim;
+ bool have_sim;
+
+ /* used by quectel uart driver */
+ GAtChat *uart;
+ struct l_timeout *mux_ready_timer;
+ int mux_ready_count;
+ int initial_ldisc;
};
static void quectel_debug(const char *str, void *user_data)
@@ -86,9 +109,67 @@ static void quectel_remove(struct ofono_modem *modem)
ofono_modem_set_data(modem, NULL);
g_at_chat_unref(data->aux);
g_at_chat_unref(data->modem);
+ g_at_chat_unref(data->uart);
l_free(data);
}
+static void close_mux_cb(struct l_timeout *timeout, void *user_data)
+{
+ struct ofono_modem *modem = user_data;
+ struct quectel_data *data = ofono_modem_get_data(modem);
+ GIOChannel *device;
+ uint32_t gpio_value = 0;
+ ssize_t write_count;
+ int fd;
+
+ DBG("%p", modem);
+
+ device = g_at_chat_get_channel(data->uart);
+ fd = g_io_channel_unix_get_fd(device);
+
+ /* restore initial tty line discipline */
+ if (ioctl(fd, TIOCSETD, &data->initial_ldisc) < 0)
+ ofono_warn("Failed to restore line discipline");
+
+ /* terminate gsm 0710 multiplexing on the modem side */
+ write_count = write(fd, gsm0710_terminate, sizeof(gsm0710_terminate));
+ if (write_count != sizeof(gsm0710_terminate))
+ ofono_warn("Failed to terminate gsm multiplexing");
+
+ g_at_chat_unref(data->uart);
+ data->uart = NULL;
+
+ l_timeout_remove(timeout);
+ ofono_modem_set_powered(modem, false);
+}
+
+static void close_serial(struct ofono_modem *modem)
+{
+ struct quectel_data *data = ofono_modem_get_data(modem);
+
+ DBG("%p", modem);
+
+ g_at_chat_unref(data->aux);
+ data->aux = NULL;
+
+ g_at_chat_unref(data->modem);
+ data->modem = NULL;
+
+ /*
+ * if gsm0710 multiplexing is used, the aux and modem file descriptors
+ * must be closed before closing the underlying serial device to avoid
+ * an old kernel dead-lock:
+ * https://lists.ofono.org/pipermail/ofono/2011-March/009405.html
+ *
+ * setup a timer to iterate the mainloop once to let gatchat close the
+ * virtual file descriptors unreferenced above
+ */
+ if (data->uart)
+ l_timeout_create_ms(1, close_mux_cb, modem, NULL);
+ else
+ ofono_modem_set_powered(modem, false);
+}
+
static void cpin_notify(GAtResult *result, gpointer user_data)
{
struct ofono_modem *modem = user_data;
@@ -106,7 +187,7 @@ static void cpin_notify(GAtResult *result, gpointer
user_data)
g_at_result_iter_next_unquoted_string(&iter, &sim_inserted);
if (g_strcmp0(sim_inserted, "NOT INSERTED") != 0)
- data->have_sim = TRUE;
+ data->have_sim = true;
ofono_modem_set_powered(modem, TRUE);
@@ -133,11 +214,7 @@ static void cfun_enable(gboolean ok, GAtResult *result,
gpointer user_data)
DBG("%p ok %d", modem, ok);
if (!ok) {
- g_at_chat_unref(data->aux);
- data->aux = NULL;
- g_at_chat_unref(data->modem);
- data->modem = NULL;
- ofono_modem_set_powered(modem, FALSE);
+ close_serial(modem);
return;
}
@@ -152,19 +229,23 @@ static void cfun_query(gboolean ok, GAtResult *result,
gpointer user_data)
struct ofono_modem *modem = user_data;
struct quectel_data *data = ofono_modem_get_data(modem);
GAtResultIter iter;
- int status;
+ int cfun;
DBG("%p ok %d", modem, ok);
- if (!ok)
+ if (!ok) {
+ close_serial(modem);
return;
+ }
g_at_result_iter_init(&iter, result);
- if (g_at_result_iter_next(&iter, "+CFUN:") == FALSE)
+ if (g_at_result_iter_next(&iter, "+CFUN:") == FALSE) {
+ close_serial(modem);
return;
+ }
- g_at_result_iter_next_number(&iter, &status);
+ g_at_result_iter_next_number(&iter, &cfun);
/*
* The modem firmware powers up in CFUN=1 but will respond to AT+CFUN=4
@@ -172,20 +253,18 @@ static void cfun_query(gboolean ok, GAtResult *result,
gpointer user_data)
* passes. Empirical evidence suggests that the firmware will report an
* unsolicited +CPIN: notification when it is ready to be useful.
*
- * Work around this feature by only transitioning to CFUN=4 after we've
- * received an unsolicited +CPIN: notification.
+ * Work around this feature by only transitioning to CFUN=4 if the
+ * modem is not in CFUN=1 or untill after we've received an unsolicited
+ * +CPIN: notification.
*/
-
- if (status != 1) {
+ if (cfun != 1)
g_at_chat_send(data->aux, "AT+CFUN=4", none_prefix, cfun_enable,
modem, NULL);
- return;
- }
-
- cfun_enable(TRUE, NULL, modem);
+ else
+ cfun_enable(TRUE, NULL, modem);
}
-static int quectel_enable(struct ofono_modem *modem)
+static int open_ttys(struct ofono_modem *modem)
{
struct quectel_data *data = ofono_modem_get_data(modem);
@@ -216,18 +295,155 @@ static int quectel_enable(struct ofono_modem *modem)
return -EINPROGRESS;
}
-static void cfun_disable(gboolean ok, GAtResult *result, gpointer user_data)
+static void mux_ready_cb(struct l_timeout *timeout, void *user_data)
{
struct ofono_modem *modem = user_data;
struct quectel_data *data = ofono_modem_get_data(modem);
+ struct stat st;
+ int i, ret;
DBG("%p", modem);
- g_at_chat_unref(data->aux);
- data->aux = NULL;
+ /* check if the last (and thus all) virtual gsm tty's are created */
+ ret = stat(ofono_modem_get_string(modem, "Modem"), &st);
+ if (ret < 0) {
+ if (data->mux_ready_count++ < 5) {
+ /* not ready yet; try again in 100 ms*/
+ l_timeout_modify_ms(timeout, 100);
+ return;
+ }
+
+ /* not ready after 500 ms; bail out */
+ close_serial(modem);
+ return;
+ }
- if (ok)
- ofono_modem_set_powered(modem, FALSE);
+ /* virtual gsm tty's are ready */
+ l_timeout_remove(timeout);
+
+ if (open_ttys(modem) != -EINPROGRESS)
+ close_serial(modem);
+
+ g_at_chat_set_slave(data->uart, data->modem);
+}
+
+static void cmux_cb(gboolean ok, GAtResult *result, gpointer user_data)
+{
+ struct ofono_modem *modem = user_data;
+ struct quectel_data *data = ofono_modem_get_data(modem);
+ struct gsm_config gsm_config;
+ GIOChannel *device;
+ int ldisc = N_GSM0710;
+ int fd;
+
+ DBG("%p", modem);
+
+ device = g_at_chat_get_channel(data->uart);
+ fd = g_io_channel_unix_get_fd(device);
+
+ /* get initial line discipline to restore after use */
+ if (ioctl(fd, TIOCGETD, &data->initial_ldisc) < 0) {
+ ofono_error("Failed to get current line discipline: %s",
strerror(errno));
+ close_serial(modem);
+ return;
+ }
+
+ /* enable gsm 0710 multiplexing line discipline */
+ if (ioctl(fd, TIOCSETD, &ldisc) < 0) {
+ ofono_error("Failed to set multiplexer line discipline: %s",
strerror(errno));
+ close_serial(modem);
+ return;
+ }
+
+ /* get n_gsm configuration */
+ if (ioctl(fd, GSMIOC_GETCONF, &gsm_config) < 0) {
+ ofono_error("Failed to get gsm config: %s", strerror(errno));
+ close_serial(modem);
+ return;
+ }
+
+ gsm_config.initiator = 1; /* cpu side is initiating multiplexing */
+ gsm_config.encapsulation = 0; /* basic transparency encoding */
+ gsm_config.mru = 127; /* 127 bytes rx mtu */
+ gsm_config.mtu = 127; /* 127 bytes tx mtu */
+ gsm_config.t1 = 10; /* 100 ms ack timer */
+ gsm_config.n2 = 3; /* 3 retries */
+ gsm_config.t2 = 30; /* 300 ms response timer */
+ gsm_config.t3 = 10; /* 100 ms wake up response timer */
+ gsm_config.i = 1; /* subset */
+
+ /* set the new configuration */
+ if (ioctl(fd, GSMIOC_SETCONF, &gsm_config) < 0) {
+ ofono_error("Failed to set gsm config: %s", strerror(errno));
+ close_serial(modem);
+ return;
+ }
+
+ /*
+ * the kernel does not yet support mapping the underlying serial device
+ * to its virtual gsm ttys, so hard-code gsmtty1 gsmtty2 for now
+ */
+ ofono_modem_set_string(modem, "Aux", "/dev/gsmtty1");
+ ofono_modem_set_string(modem, "Modem", "/dev/gsmtty2");
+
+ /* wait for gsmtty devices to appear */
+ if (!l_timeout_create_ms(100, mux_ready_cb, modem, NULL)) {
+ close_serial(modem);
+ return;
+ }
+}
+
+static int open_serial(struct ofono_modem *modem)
+{
+ struct quectel_data *data = ofono_modem_get_data(modem);
+ const char *rts_cts;
+
+ DBG("%p", modem);
+
+ rts_cts = ofono_modem_get_string(modem, "RtsCts");
+
+ data->uart = at_util_open_device(modem, "Device", quectel_debug,
+ "UART: ",
+ "Baud", "115200",
+ "Parity", "none",
+ "StopBits", "1",
+ "DataBits", "8",
+ "XonXoff", "off",
+ "Local", "on",
+ "Read", "on",
+ "RtsCts", rts_cts,
+ NULL);
+ if (data->uart == NULL)
+ return -EINVAL;
+
+ g_at_chat_send(data->uart, "ATE0", none_prefix, NULL, NULL,
+ NULL);
+
+ /* setup multiplexing */
+ g_at_chat_send(data->uart, "AT+CMUX=0,0,5,127,10,3,30,10,2", NULL,
+ cmux_cb, modem, NULL);
+
+ return -EINPROGRESS;
+}
+
+static int quectel_enable(struct ofono_modem *modem)
+{
+ DBG("%p", modem);
+
+ if (ofono_modem_get_string(modem, "Device"))
+ return open_serial(modem);
+ else
+ return open_ttys(modem);
+}
+
+static void cfun_disable(gboolean ok, GAtResult *result, gpointer user_data)
+{
+ struct ofono_modem *modem = user_data;
+ struct quectel_data *data = ofono_modem_get_data(modem);
+
+ DBG("%p", modem);
+
+ close_serial(modem);
}
static int quectel_disable(struct ofono_modem *modem)
@@ -239,14 +455,11 @@ static int quectel_disable(struct ofono_modem *modem)
g_at_chat_cancel_all(data->modem);
g_at_chat_unregister_all(data->modem);
- g_at_chat_unref(data->modem);
- data->modem = NULL;
-
g_at_chat_cancel_all(data->aux);
g_at_chat_unregister_all(data->aux);
- g_at_chat_send(data->aux, "AT+CFUN=0", cfun_prefix,
- cfun_disable, modem, NULL);
+ g_at_chat_send(data->aux, "AT+CFUN=0", cfun_prefix, cfun_disable, modem,
+ NULL);
return -EINPROGRESS;
}
@@ -292,7 +505,7 @@ static void quectel_pre_sim(struct ofono_modem *modem)
sim = ofono_sim_create(modem, OFONO_VENDOR_QUECTEL, "atmodem",
data->aux);
- if (sim && data->have_sim == TRUE)
+ if (sim && data->have_sim == true)
ofono_sim_inserted_notify(sim, TRUE);
}
diff --git a/plugins/udevng.c b/plugins/udevng.c
index 4b420dc0..567196bc 100644
--- a/plugins/udevng.c
+++ b/plugins/udevng.c
@@ -837,7 +837,7 @@ static gboolean setup_samsung(struct modem_info *modem)
return TRUE;
}
-static gboolean setup_quectel(struct modem_info *modem)
+static gboolean setup_quectel_usb(struct modem_info *modem)
{
const char *aux = NULL, *mdm = NULL;
GSList *list;
@@ -877,6 +877,28 @@ static gboolean setup_quectel(struct modem_info *modem)
return TRUE;
}
+static gboolean setup_quectel_serial(struct modem_info *modem)
+{
+ struct serial_device_info* info;
+ const char *value;
+
+ info = modem->serial;
+ value = udev_device_get_property_value(info->dev,
"OFONO_QUECTEL_RTSCTS");
+
+ ofono_modem_set_string(modem->modem, "RtsCts", value ? value : "off");
+ ofono_modem_set_string(modem->modem, "Device", info->devnode);
+
+ return TRUE;
+}
+
+static gboolean setup_quectel(struct modem_info *modem)
+{
+ if (modem->serial)
+ return setup_quectel_serial(modem);
+ else
+ return setup_quectel_usb(modem);
+}
+
static gboolean setup_quectelqmi(struct modem_info *modem)
{
const char *qmi = NULL, *net = NULL, *gps = NULL, *aux = NULL;
--
2.22.0
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