ACPI / LPSS: do delay for all LPSS devices when D3->D0

The LPSS DMA device has no context to save, though it requires the same delay
like the rest of LPSS devices when power state is changed from D3 to D0.

Do delay for the DMA device as well.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/acpi/acpi_lpss.c b/drivers/acpi/acpi_lpss.c
index 6263939..bd3e84a 100644
--- a/drivers/acpi/acpi_lpss.c
+++ b/drivers/acpi/acpi_lpss.c
@@ -574,6 +574,17 @@
 {
 	unsigned int i;
 
+	for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
+		unsigned long offset = i * sizeof(u32);
+
+		__lpss_reg_write(pdata->prv_reg_ctx[i], pdata, offset);
+		dev_dbg(dev, "restoring 0x%08x to LPSS reg at offset 0x%02lx\n",
+			pdata->prv_reg_ctx[i], offset);
+	}
+}
+
+static void acpi_lpss_d3_to_d0_delay(struct lpss_private_data *pdata)
+{
 	/*
 	 * The following delay is needed or the subsequent write operations may
 	 * fail. The LPSS devices are actually PCI devices and the PCI spec
@@ -586,14 +597,6 @@
 		delay = 0;
 
 	msleep(delay);
-
-	for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
-		unsigned long offset = i * sizeof(u32);
-
-		__lpss_reg_write(pdata->prv_reg_ctx[i], pdata, offset);
-		dev_dbg(dev, "restoring 0x%08x to LPSS reg at offset 0x%02lx\n",
-			pdata->prv_reg_ctx[i], offset);
-	}
 }
 
 #ifdef CONFIG_PM_SLEEP
@@ -621,6 +624,8 @@
 	if (ret)
 		return ret;
 
+	acpi_lpss_d3_to_d0_delay(pdata);
+
 	if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
 		acpi_lpss_restore_ctx(dev, pdata);
 
@@ -652,6 +657,8 @@
 	if (ret)
 		return ret;
 
+	acpi_lpss_d3_to_d0_delay(pdata);
+
 	if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
 		acpi_lpss_restore_ctx(dev, pdata);