serial: ifx6x60: Add module parameters to manage the modem status through sysfs.

index e56ed33..50de856 100644
@@ -72,6 +72,19 @@
 #define IFX_SPI_HEADER_0		(-1)
 #define IFX_SPI_HEADER_F		(-2)
 
+
+/* Delays for powering up/resetting the modem, ms */
+#define PO_INTERLINE_DELAY	1
+#define PO_POST_DELAY		200
+
+#define IFX_COLD_RESET_REQ	1
+
+#define IFX_MDM_PWR_ON	3
+#define IFX_MDM_RST_PMU	4
+
+static unsigned long  reset_ongoing;
+static unsigned long hangup_reasons;
+
 /* forward reference */
 static void ifx_spi_handle_srdy(struct ifx_spi_device *ifx_dev);
 

@@ -81,6 +94,42 @@ static struct tty_driver *tty_drv;
 static struct ifx_spi_device *saved_ifx_dev;
 static struct lock_class_key ifx_spi_key;
 
+
+/**
+ * do_modem_power - activity required to bring up modem
+ *
+ * Toggle gpios required to bring up modem power and start modem.
+ */
+static void do_modem_power(void)
+{
+
+	reset_ongoing = 1;
+
+
+	gpio_set_value(IFX_MDM_PWR_ON, 1);
+	mdelay(PO_INTERLINE_DELAY);
+	gpio_set_value(IFX_MDM_PWR_ON, 0);
+	msleep(PO_POST_DELAY);
+}
+
+/**
+ * do_modem_reset - activity required to reset modem
+ *
+ * Toggle gpios required to reset modem.
+ */
+static void do_modem_reset(void)
+{
+
+	reset_ongoing = 1;
+
+	gpio_set_value(IFX_MDM_RST_PMU, 0);
+	mdelay(PO_INTERLINE_DELAY);
+	gpio_set_value(IFX_MDM_RST_PMU, 1);
+	msleep(PO_POST_DELAY);
+}
+
+
+
 /* GPIO/GPE settings */
 
 /**

@@ -227,6 +276,7 @@ static void ifx_spi_timeout(unsigned long arg)
 	struct ifx_spi_device *ifx_dev = (struct ifx_spi_device *)arg;
 
 	dev_warn(&ifx_dev->spi_dev->dev, "*** SPI Timeout ***");
+	hangup_reasons |= HU_TIMEOUT;
 	ifx_spi_ttyhangup(ifx_dev);
 	mrdy_set_low(ifx_dev);
 	clear_bit(IFX_SPI_STATE_TIMER_PENDING, &ifx_dev->flags);

@@ -877,6 +927,7 @@ static irqreturn_t ifx_spi_reset_interrupt(int irq, void *dev)
 		}
 	} else {
 		/* exited reset */
+		reset_ongoing = 0 ;
 		clear_bit(MR_INPROGRESS, &ifx_dev->mdm_reset_state);
 		if (solreset) {
 			set_bit(MR_COMPLETE, &ifx_dev->mdm_reset_state);

@@ -1403,6 +1454,63 @@ static int __init ifx_spi_init(void)
 module_init(ifx_spi_init);
 module_exit(ifx_spi_exit);
 
+/*
+ * Module parameters to manage the modem status through sysfs
+ */
+
+/**
+ * reset_modem - modem reset command function
+ * @val: a reference to the string where the modem reset query is given
+ * @kp: an unused reference to the kernel parameter
+ */
+
+static int reset_modem(const char *val, const struct kernel_param *kp)
+{
+	unsigned long reset_request;
+
+	if (kstrtoul(val, 10, &reset_request) < 0)
+		return -EINVAL;
+
+	if (!saved_ifx_dev) {
+		dev_dbg(&saved_ifx_dev->spi_dev->dev,
+				"%s is called before probe\n", __func__);
+		return -ENODEV;
+	}
+
+	dev_dbg(&saved_ifx_dev->spi_dev->dev,
+					"%s requested !\n", __func__);
+
+	reset_ongoing = 1;
+
+	if (reset_request == IFX_COLD_RESET_REQ) {
+		/*  Need to add these action for modem cold reset:
+		* - Set the RESET_BB_N to low (better SIM protection)
+		* - Set the EXT1P35VREN field to low  during 20ms (V1P35CNT_W  register)
+		* - set the EXT1P35VREN field to high during 10ms (V1P35CNT_W  register)
+		*/
+	}
+
+	/* Perform a complete modem reset */
+	do_modem_reset();
+	do_modem_power();
+
+	return 0;
+}
+
+static struct kernel_param_ops reset_modem_ops = {
+	.set = reset_modem,
+};
+module_param_cb(reset_modem, &reset_modem_ops, NULL, 0644);
+
+
+module_param(reset_ongoing, ulong, S_IRUGO);
+MODULE_PARM_DESC(reset_ongoing,  "modem reset status module parameter");
+
+module_param(hangup_reasons, ulong, S_IRUGO|S_IWUSR);
+MODULE_PARM_DESC(hangup_reasons, "modem hangup reasons module parameter ");
+
+
+
 MODULE_AUTHOR("Intel");
 MODULE_DESCRIPTION("IFX6x60 spi driver");
 MODULE_LICENSE("GPL");

index e8464ba..1ac36c4 100644
@@ -66,6 +66,13 @@
 #define IFX_SPI_POWER_DATA_PENDING	1
 #define IFX_SPI_POWER_SRDY		2
 
+
+/* reasons for hanging up */
+#define	HU_TIMEOUT		1	/* spi timer out */
+#define	HU_RESET			2	/* modem initiative reset */
+#define	HU_COREDUMP		4	/* modem crash coredump */
+#define	HU_RORTUR			8	/* spi transfer error:ROR or TUR */
+
 struct ifx_spi_device {
 	/* Our SPI device */
 	struct spi_device *spi_dev;