1 files changed, 35 insertions, 18 deletions

diff --git a/drivers/acpi/acpi_lpss.c b/drivers/acpi/acpi_lpss.c
index 93d160661f4c..f6b71afb80ea 100644
--- a/drivers/acpi/acpi_lpss.c
+++ b/drivers/acpi/acpi_lpss.c
@@ -499,14 +499,15 @@ static void acpi_lpss_set_ltr(struct device *dev, s32 val)
 /**
  * acpi_lpss_save_ctx() - Save the private registers of LPSS device
  * @dev: LPSS device
+ * @pdata: pointer to the private data of the LPSS device
  *
  * Most LPSS devices have private registers which may loose their context when
  * the device is powered down. acpi_lpss_save_ctx() saves those registers into
  * prv_reg_ctx array.
  */
-static void acpi_lpss_save_ctx(struct device *dev)
+static void acpi_lpss_save_ctx(struct device *dev,
+                               struct lpss_private_data *pdata)
 {
-        struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
         unsigned int i;
 
         for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
@@ -521,12 +522,13 @@ static void acpi_lpss_save_ctx(struct device *dev)
 /**
  * acpi_lpss_restore_ctx() - Restore the private registers of LPSS device
  * @dev: LPSS device
+ * @pdata: pointer to the private data of the LPSS device
  *
  * Restores the registers that were previously stored with acpi_lpss_save_ctx().
  */
-static void acpi_lpss_restore_ctx(struct device *dev)
+static void acpi_lpss_restore_ctx(struct device *dev,
+                                  struct lpss_private_data *pdata)
 {
-        struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
         unsigned int i;
 
         /*
@@ -549,23 +551,31 @@ static void acpi_lpss_restore_ctx(struct device *dev)
 #ifdef CONFIG_PM_SLEEP
 static int acpi_lpss_suspend_late(struct device *dev)
 {
-        int ret = pm_generic_suspend_late(dev);
+        struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
+        int ret;
 
+        ret = pm_generic_suspend_late(dev);
         if (ret)
                 return ret;
 
-        acpi_lpss_save_ctx(dev);
+        if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
+                acpi_lpss_save_ctx(dev, pdata);
+
         return acpi_dev_suspend_late(dev);
 }
 
 static int acpi_lpss_resume_early(struct device *dev)
 {
-        int ret = acpi_dev_resume_early(dev);
+        struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
+        int ret;
 
+        ret = acpi_dev_resume_early(dev);
         if (ret)
                 return ret;
 
-        acpi_lpss_restore_ctx(dev);
+        if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
+                acpi_lpss_restore_ctx(dev, pdata);
+
         return pm_generic_resume_early(dev);
 }
 #endif /* CONFIG_PM_SLEEP */
@@ -573,23 +583,31 @@ static int acpi_lpss_resume_early(struct device *dev)
 #ifdef CONFIG_PM_RUNTIME
 static int acpi_lpss_runtime_suspend(struct device *dev)
 {
-        int ret = pm_generic_runtime_suspend(dev);
+        struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
+        int ret;
 
+        ret = pm_generic_runtime_suspend(dev);
         if (ret)
                 return ret;
 
-        acpi_lpss_save_ctx(dev);
+        if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
+                acpi_lpss_save_ctx(dev, pdata);
+
         return acpi_dev_runtime_suspend(dev);
 }
 
 static int acpi_lpss_runtime_resume(struct device *dev)
 {
-        int ret = acpi_dev_runtime_resume(dev);
+        struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
+        int ret;
 
+        ret = acpi_dev_runtime_resume(dev);
         if (ret)
                 return ret;
 
-        acpi_lpss_restore_ctx(dev);
+        if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
+                acpi_lpss_restore_ctx(dev, pdata);
+
         return pm_generic_runtime_resume(dev);
 }
 #endif /* CONFIG_PM_RUNTIME */
@@ -631,22 +649,21 @@ static int acpi_lpss_platform_notify(struct notifier_block *nb,
                 return 0;
 
         pdata = acpi_driver_data(adev);
-        if (!pdata || !pdata->mmio_base)
+        if (!pdata)
                 return 0;
 
-        if (pdata->mmio_size < pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) {
+        if (pdata->mmio_base &&
+            pdata->mmio_size < pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) {
                 dev_err(&pdev->dev, "MMIO size insufficient to access LTR\n");
                 return 0;
         }
 
         switch (action) {
         case BUS_NOTIFY_BOUND_DRIVER:
-                if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
-                        pdev->dev.pm_domain = &acpi_lpss_pm_domain;
+                pdev->dev.pm_domain = &acpi_lpss_pm_domain;
                 break;
         case BUS_NOTIFY_UNBOUND_DRIVER:
-                if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
-                        pdev->dev.pm_domain = NULL;
+                pdev->dev.pm_domain = NULL;
                 break;
         case BUS_NOTIFY_ADD_DEVICE:
                 if (pdata->dev_desc->flags & LPSS_LTR)