ARM: tegra: baseband: modem flashless boot and remote wakeup

Support modem reboot and re-enumeration.
Support modem remote wakeup.

Bug 814261
Bug 814271
Bug 846135

Original-Change-Id: I103722d0248bcb1565d5f5799a2e4317c2579a95
Reviewed-on: http://git-master/r/31441
Tested-by: Szming Lin <stlin@nvidia.com>
Reviewed-by: Udaykumar Rameshchan Raval <uraval@nvidia.com>
Reviewed-by: Scott Williams <scwilliams@nvidia.com>

Rebase-Id: Rd1a0b91d4708fc039648df0cd491c9a382b5fcb2

1 files changed, 238 insertions, 39 deletions

diff --git a/arch/arm/mach-tegra/board-enterprise-baseband.c b/arch/arm/mach-tegra/board-enterprise-baseband.c
index 285f01dcdb24..eefb230599ff 100644
--- a/arch/arm/mach-tegra/board-enterprise-baseband.c
+++ b/arch/arm/mach-tegra/board-enterprise-baseband.c
@@ -22,7 +22,11 @@
 #include <linux/platform_device.h>
 #include <linux/delay.h>
 #include <linux/gpio.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
 #include <linux/err.h>
+#include <linux/device.h>
+#include <linux/usb.h>
 #include <linux/platform_data/tegra_usb.h>
 #include <asm/mach-types.h>
 #include <asm/mach/arch.h>
@@ -31,24 +35,50 @@
 #include "devices.h"
 #include "gpio-names.h"
 
-/* T30 BB GPIO */
-#define MODEM_PWR_ON	TEGRA_GPIO_PE0
-#define MODEM_RESET	TEGRA_GPIO_PE1
+#define ENABLE_AUTO_SUSPEND     0
+#define ENABLE_HOST_RECOVERY    0	/* flashless only feature */
 
-/* PH450 */
-#define AP2MDM_ACK	TEGRA_GPIO_PE3
-#define MDM2AP_ACK	TEGRA_GPIO_PU5
-#define AP2MDM_ACK2	TEGRA_GPIO_PE2
-#define MDM2AP_ACK2	TEGRA_GPIO_PV0
+/* Tegra3 BB GPIO */
+#define MODEM_PWR_ON    TEGRA_GPIO_PE0
+#define MODEM_RESET     TEGRA_GPIO_PE1
+#define BB_RST_OUT      TEGRA_GPIO_PV1
+
+/* PH450 GPIO */
+#define AP2MDM_ACK      TEGRA_GPIO_PE3
+#define MDM2AP_ACK      TEGRA_GPIO_PU5
+#define AP2MDM_ACK2     TEGRA_GPIO_PE2
+#define MDM2AP_ACK2     TEGRA_GPIO_PV0
+
+struct ph450_priv {
+	unsigned int wake_gpio;
+	unsigned int wake_cnt;
+	unsigned int restart_gpio;
+	struct mutex lock;
+	unsigned int vid;
+	unsigned int pid;
+	struct usb_device *udev;
+	struct usb_interface *intf;
+	struct workqueue_struct *wq;
+	struct delayed_work reset_work;
+};
+
+static struct usb_device_id modem_list[] = {
+	{
+	 .match_flags = USB_DEVICE_ID_MATCH_VENDOR,
+	 .idVendor = 0x1983,
+	 },
+	{},
+};
 
 static int ph450_reset(void);
 static int ph450_handshake(void);
 
+static struct ph450_priv ph450_priv;
 static struct tegra_ulpi_trimmer e1219_trimmer = { 10, 1, 1, 1 };
 
 static struct tegra_ulpi_config ehci2_null_ulpi_phy_config = {
 	.trimmer = &e1219_trimmer,
-	.preinit = ph450_reset,
+	.preinit = NULL,
 	.postinit = ph450_handshake,
 };
 
@@ -66,8 +96,147 @@ static int __init tegra_null_ulpi_init(void)
 	return 0;
 }
 
+static void device_add_handler(struct usb_device *udev)
+{
+	const struct usb_device_descriptor *desc = &udev->descriptor;
+	struct usb_interface *intf = usb_ifnum_to_if(udev, 0);
+
+	if (usb_match_id(intf, modem_list)) {
+		pr_info("Add device %d <%s %s>\n", udev->devnum,
+			udev->manufacturer, udev->product);
+
+		mutex_lock(&ph450_priv.lock);
+		ph450_priv.udev = udev;
+		ph450_priv.intf = intf;
+		ph450_priv.vid = desc->idVendor;
+		ph450_priv.pid = desc->idProduct;
+		ph450_priv.wake_cnt = 0;
+		mutex_unlock(&ph450_priv.lock);
+
+		pr_info("persist_enabled: %u\n", udev->persist_enabled);
+
+#if ENABLE_AUTO_SUSPEND
+		usb_enable_autosuspend(udev);
+		pr_info("enable autosuspend for %s %s\n", udev->manufacturer,
+			udev->product);
+#endif
+	}
+}
+
+static void device_remove_handler(struct usb_device *udev)
+{
+	const struct usb_device_descriptor *desc = &udev->descriptor;
+
+	if (desc->idVendor == ph450_priv.vid
+	    && desc->idProduct == ph450_priv.pid) {
+		pr_info("Remove device %d <%s %s>\n", udev->devnum,
+			udev->manufacturer, udev->product);
+
+		mutex_lock(&ph450_priv.lock);
+		ph450_priv.udev = NULL;
+		ph450_priv.intf = NULL;
+		ph450_priv.vid = 0;
+		mutex_unlock(&ph450_priv.lock);
+
+#if ENABLE_HOST_RECOVERY
+		queue_delayed_work(ph450_priv.wq, &ph450_priv.reset_work,
+				   HZ * 10);
+#endif
+	}
+}
+
+static int usb_notify(struct notifier_block *self, unsigned long action,
+		      void *blob)
+{
+	switch (action) {
+	case USB_DEVICE_ADD:
+		device_add_handler(blob);
+		break;
+	case USB_DEVICE_REMOVE:
+		device_remove_handler(blob);
+		break;
+	}
+
+	return NOTIFY_OK;
+}
+
+static struct notifier_block usb_nb = {
+	.notifier_call = usb_notify,
+};
+
+static irqreturn_t mdm_start_thread(int irq, void *data)
+{
+	struct ph450_priv *priv = (struct ph450_priv *)data;
+
+	if (gpio_get_value(priv->restart_gpio)) {
+		pr_info("BB_RST_OUT high\n");
+		gpio_set_value(AP2MDM_ACK2, 1);
+	} else {
+		pr_info("BB_RST_OUT low\n");
+		gpio_set_value(AP2MDM_ACK2, 0);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t mdm_wake_thread(int irq, void *data)
+{
+	struct ph450_priv *priv = (struct ph450_priv *)data;
+
+	if (gpio_get_value(priv->wake_gpio) == 0) {
+		pr_info("MDM2AP_ACK2 low\n");
+
+		mutex_lock(&priv->lock);
+		if (priv->udev) {
+			usb_lock_device(priv->udev);
+			pr_info("mdm wake (%u)\n", ++(priv->wake_cnt));
+			if (usb_autopm_get_interface(priv->intf) == 0)
+				usb_autopm_put_interface_async(priv->intf);
+			usb_unlock_device(priv->udev);
+		}
+		mutex_unlock(&priv->lock);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static int ph450_reset(void)
+{
+	pr_info("modem reset\n");
+
+	gpio_set_value(AP2MDM_ACK2, 1);
+	gpio_set_value(MODEM_PWR_ON, 0);
+	gpio_set_value(MODEM_RESET, 0);
+	mdelay(200);
+	gpio_set_value(MODEM_RESET, 1);
+	mdelay(30);
+	gpio_set_value(MODEM_PWR_ON, 1);
+
+	return 0;
+}
+
+static int ph450_handshake(void)
+{
+	/* set AP2MDM_ACK2 low */
+	gpio_set_value(AP2MDM_ACK2, 0);
+
+	return 0;
+}
+
+static void ph450_reset_work_handler(struct work_struct *ws)
+{
+	struct ph450_priv *priv = container_of(ws, struct ph450_priv,
+					       reset_work.work);
+
+	mutex_lock(&priv->lock);
+	if (!priv->udev)	/* assume modem crashed */
+		ph450_reset();
+	mutex_unlock(&priv->lock);
+}
+
 static int __init ph450_init(void)
 {
+	int irq;
 	int ret;
 
 	ret = gpio_request(MODEM_PWR_ON, "mdm_power");
@@ -93,54 +262,83 @@ static int __init ph450_init(void)
 		return ret;
 	}
 
-	/* enable pull-up for MDM2AP_ACK2 */
+	ret = gpio_request(BB_RST_OUT, "bb_rst_out");
+	if (ret) {
+		gpio_free(MODEM_PWR_ON);
+		gpio_free(MODEM_RESET);
+		gpio_free(AP2MDM_ACK2);
+		gpio_free(MDM2AP_ACK2);
+		return ret;
+	}
+
+	/* enable pull-up for MDM2AP_ACK2 and BB_RST_OUT */
 	tegra_pinmux_set_pullupdown(TEGRA_PINGROUP_GPIO_PV0,
 				    TEGRA_PUPD_PULL_UP);
 
+	tegra_pinmux_set_pullupdown(TEGRA_PINGROUP_GPIO_PV1,
+				    TEGRA_PUPD_PULL_UP);
+
 	tegra_gpio_enable(MODEM_PWR_ON);
 	tegra_gpio_enable(MODEM_RESET);
 	tegra_gpio_enable(AP2MDM_ACK2);
 	tegra_gpio_enable(MDM2AP_ACK2);
+	tegra_gpio_enable(BB_RST_OUT);
 
 	gpio_direction_output(MODEM_PWR_ON, 0);
 	gpio_direction_output(MODEM_RESET, 0);
 	gpio_direction_output(AP2MDM_ACK2, 1);
 	gpio_direction_input(MDM2AP_ACK2);
+	gpio_direction_input(BB_RST_OUT);
 
-	return 0;
-}
+	/* reset modem */
+	ph450_reset();
 
-static int ph450_reset(void)
-{
-	int retry = 100; /* retry for 10 sec */
+	ph450_priv.wake_gpio = TEGRA_GPIO_PV0;
+	ph450_priv.restart_gpio = TEGRA_GPIO_PV1;
 
-	gpio_set_value(AP2MDM_ACK2, 1);
-	gpio_set_value(MODEM_PWR_ON, 0);
-	gpio_set_value(MODEM_RESET, 0);
-	mdelay(200);
-	gpio_set_value(MODEM_RESET, 1);
-	mdelay(30);
-	gpio_set_value(MODEM_PWR_ON, 1);
+	mutex_init(&(ph450_priv.lock));
 
-	while (retry) {
-		/* wait for MDM2AP_ACK2 low */
-		int val = gpio_get_value(MDM2AP_ACK2);
-		if (!val) {
-			pr_info("MDM2AP_ACK2 detected\n");
-			return 0;
-		} else {
-			pr_info(".");
-			retry--;
-			mdelay(100);
-		}
+	/* create work queue */
+	ph450_priv.wq = create_workqueue("mdm_queue");
+	INIT_DELAYED_WORK(&(ph450_priv.reset_work), ph450_reset_work_handler);
+
+	usb_register_notify(&usb_nb);
+
+	/* enable IRQ for BB_RST_OUT */
+	irq = gpio_to_irq(TEGRA_GPIO_PV1);
+
+	ret = request_threaded_irq(irq, NULL, mdm_start_thread,
+				   IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
+				   "mdm_start", &ph450_priv);
+	if (ret < 0) {
+		pr_err("%s: request_threaded_irq error\n", __func__);
+		return ret;
 	}
-	return 1;
-}
 
-static int ph450_handshake(void)
-{
-	/* set AP2MDM_ACK2 low */
-	gpio_set_value(AP2MDM_ACK2, 0);
+	ret = enable_irq_wake(irq);
+	if (ret) {
+		pr_err("%s: enable_irq_wake error\n", __func__);
+		free_irq(irq, &ph450_priv);
+		return ret;
+	}
+
+	/* enable IRQ for MDM2AP_ACK2 */
+	irq = gpio_to_irq(TEGRA_GPIO_PV0);
+
+	ret = request_threaded_irq(irq, NULL, mdm_wake_thread,
+				   IRQF_TRIGGER_FALLING, "mdm_wake",
+				   &ph450_priv);
+	if (ret < 0) {
+		pr_err("%s: request_threaded_irq error\n", __func__);
+		return ret;
+	}
+
+	ret = enable_irq_wake(irq);
+	if (ret) {
+		pr_err("%s: enable_irq_wake error\n", __func__);
+		free_irq(irq, &ph450_priv);
+		return ret;
+	}
 
 	return 0;
 }
@@ -156,5 +354,6 @@ int __init enterprise_modem_init(void)
 	}
 
 	tegra_null_ulpi_init();
+
 	return 0;
 }