arm: tegra: xmm: device set to null in unregister

hsic_unregister is being called multiple times
during two step enumeration process of xmm.
In failure cases when enumeration does not
complete properly, kernel panic is seen because
of extra unregister-ehci device.

Bug 1016593

Change-Id: Ibaeb20ed0dab0e906741fdfad78f7d89a3672f60
Signed-off-by: Vinayak Pane <vpane@nvidia.com>
Reviewed-on: http://git-master/r/116626
Reviewed-by: Simone Willett <swillett@nvidia.com>
Tested-by: Simone Willett <swillett@nvidia.com>

6 files changed, 16 insertions, 11 deletions

diff --git a/arch/arm/mach-tegra/baseband-xmm-power.c b/arch/arm/mach-tegra/baseband-xmm-power.c
index f85d6e6c48b6..5a7cecde526b 100644
--- a/arch/arm/mach-tegra/baseband-xmm-power.c
+++ b/arch/arm/mach-tegra/baseband-xmm-power.c
@@ -66,7 +66,7 @@ static struct usb_device_id xmm_pm_ids[] = {
 	.driver_info = 0 },
 	{}
 };
-
+MODULE_DEVICE_TABLE(usb, xmm_pm_ids);
 
 static struct gpio tegra_baseband_gpios[] = {
 	{ -1, GPIOF_OUT_INIT_LOW,  "BB_RSTn" },
@@ -348,11 +348,10 @@ static int xmm_power_off(struct platform_device *device)
 
 	/* unregister usb host controller */
 	if (pdata->hsic_unregister)
-		pdata->hsic_unregister(data->hsic_device);
+		pdata->hsic_unregister(&data->hsic_device);
 	else
 		pr_err("%s: hsic_unregister is missing\n", __func__);
 
-
 	/* set IPC_HSIC_ACTIVE low */
 	gpio_set_value(pdata->modem.xmm.ipc_hsic_active, 0);
 
@@ -819,7 +818,7 @@ static void xmm_device_remove_handler(struct usb_device *udev)
 	if (usbdev == udev) {
 		pr_info("Remove device %d <%s %s>\n", udev->devnum,
 			udev->manufacturer, udev->product);
-		usbdev = 0;
+		usbdev = NULL;
 	}
 
 }
@@ -1038,7 +1037,7 @@ static int xmm_power_driver_remove(struct platform_device *device)
 
 	/* unregister usb host controller */
 	if (pdata->hsic_unregister)
-		pdata->hsic_unregister(data->hsic_device);
+		pdata->hsic_unregister(&data->hsic_device);
 	else
 		pr_err("%s: hsic_unregister is missing\n", __func__);
 
diff --git a/arch/arm/mach-tegra/baseband-xmm-power.h b/arch/arm/mach-tegra/baseband-xmm-power.h
index 0c8723fe6766..55c81833ba04 100644
--- a/arch/arm/mach-tegra/baseband-xmm-power.h
+++ b/arch/arm/mach-tegra/baseband-xmm-power.h
@@ -41,7 +41,7 @@ enum baseband_type {
 struct baseband_power_platform_data {
 	enum baseband_type baseband_type;
 	struct platform_device* (*hsic_register)(void);
-	void (*hsic_unregister)(struct platform_device *);
+	void (*hsic_unregister)(struct platform_device **);
 	union {
 		struct {
 			int mdm_reset;
diff --git a/arch/arm/mach-tegra/baseband-xmm-power2.c b/arch/arm/mach-tegra/baseband-xmm-power2.c
index 905759dca329..a79cd6fb499f 100644
--- a/arch/arm/mach-tegra/baseband-xmm-power2.c
+++ b/arch/arm/mach-tegra/baseband-xmm-power2.c
@@ -108,7 +108,7 @@ static void xmm_power2_step1(struct work_struct *work)
 
 	/* unregister usb host controller */
 	if (pdata->hsic_unregister)
-		pdata->hsic_unregister(data->hsic_device);
+		pdata->hsic_unregister(&data->hsic_device);
 	else
 		pr_err("%s: hsic_unregister is missing\n", __func__);
 
diff --git a/arch/arm/mach-tegra/board-enterprise.c b/arch/arm/mach-tegra/board-enterprise.c
index 46078a82a9b1..d918a1fb3518 100644
--- a/arch/arm/mach-tegra/board-enterprise.c
+++ b/arch/arm/mach-tegra/board-enterprise.c
@@ -832,9 +832,15 @@ error:
 	return NULL;
 }
 
-void tegra_usb_hsic_host_unregister(struct platform_device *pdev)
+void tegra_usb_hsic_host_unregister(struct platform_device **platdev)
 {
-	platform_device_unregister(pdev);
+	struct platform_device *pdev = *platdev;
+
+	if (pdev && &pdev->dev) {
+		platform_device_unregister(pdev);
+		*platdev = NULL;
+	} else
+		pr_err("%s: no platform device\n", __func__);
 }
 
 static void enterprise_usb_init(void)
diff --git a/arch/arm/mach-tegra/include/mach/tegra-bb-power.h b/arch/arm/mach-tegra/include/mach/tegra-bb-power.h
index e0b7e3de326f..96e36116f04f 100644
--- a/arch/arm/mach-tegra/include/mach/tegra-bb-power.h
+++ b/arch/arm/mach-tegra/include/mach/tegra-bb-power.h
@@ -50,7 +50,7 @@ union tegra_bb_gpio_id {
 };
 
 typedef struct platform_device* (*ehci_register_cb)(void);
-typedef void (*ehci_unregister_cb)(struct platform_device *);
+typedef void (*ehci_unregister_cb)(struct platform_device **);
 
 struct tegra_bb_pdata {
 	union tegra_bb_gpio_id *id;
diff --git a/drivers/misc/tegra-baseband/bb-m7400.c b/drivers/misc/tegra-baseband/bb-m7400.c
index adabefdb100d..edde7d1786ed 100644
--- a/drivers/misc/tegra-baseband/bb-m7400.c
+++ b/drivers/misc/tegra-baseband/bb-m7400.c
@@ -241,7 +241,7 @@ static int m7400_attrib_write(struct device *dev, int value)
 	} else {
 		/* Unregister ehci controller */
 		if (ehci_device != NULL)
-			pdata->ehci_unregister(ehci_device);
+			pdata->ehci_unregister(&ehci_device);
 
 		/* Signal AP going down */
 		m7400_apdown_handshake();