4 files changed, 45 insertions, 7 deletions

diff --git a/drivers/i2c/busses/i2c-designware-core.c b/drivers/i2c/busses/i2c-designware-core.c
index 809f4d4e93a0..340e037b3224 100644
--- a/drivers/i2c/busses/i2c-designware-core.c
+++ b/drivers/i2c/busses/i2c-designware-core.c
@@ -507,7 +507,7 @@ static void i2c_dw_xfer_init(struct dw_i2c_dev *dev)
 	i2c_dw_disable_int(dev);
 
 	/* Enable the adapter */
-	__i2c_dw_enable(dev, true);
+	__i2c_dw_enable_and_wait(dev, true);
 
 	/* Clear and enable interrupts */
 	dw_readl(dev, DW_IC_CLR_INTR);
diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
index e6fe21a6135b..b32bf7eac3c8 100644
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -243,6 +243,7 @@ struct i801_priv {
 	struct i2c_adapter adapter;
 	unsigned long smba;
 	unsigned char original_hstcfg;
+	unsigned char original_slvcmd;
 	struct pci_dev *pci_dev;
 	unsigned int features;
 
@@ -962,13 +963,24 @@ static int i801_enable_host_notify(struct i2c_adapter *adapter)
 	if (!priv->host_notify)
 		return -ENOMEM;
 
-	outb_p(SMBSLVCMD_HST_NTFY_INTREN, SMBSLVCMD(priv));
+	if (!(SMBSLVCMD_HST_NTFY_INTREN & priv->original_slvcmd))
+		outb_p(SMBSLVCMD_HST_NTFY_INTREN | priv->original_slvcmd,
+		       SMBSLVCMD(priv));
+
 	/* clear Host Notify bit to allow a new notification */
 	outb_p(SMBSLVSTS_HST_NTFY_STS, SMBSLVSTS(priv));
 
 	return 0;
 }
 
+static void i801_disable_host_notify(struct i801_priv *priv)
+{
+	if (!(priv->features & FEATURE_HOST_NOTIFY))
+		return;
+
+	outb_p(priv->original_slvcmd, SMBSLVCMD(priv));
+}
+
 static const struct i2c_algorithm smbus_algorithm = {
 	.smbus_xfer	= i801_access,
 	.functionality	= i801_func,
@@ -1589,6 +1601,10 @@ static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
 		outb_p(inb_p(SMBAUXCTL(priv)) &
 		       ~(SMBAUXCTL_CRC | SMBAUXCTL_E32B), SMBAUXCTL(priv));
 
+	/* Remember original Host Notify setting */
+	if (priv->features & FEATURE_HOST_NOTIFY)
+		priv->original_slvcmd = inb_p(SMBSLVCMD(priv));
+
 	/* Default timeout in interrupt mode: 200 ms */
 	priv->adapter.timeout = HZ / 5;
 
@@ -1666,6 +1682,7 @@ static void i801_remove(struct pci_dev *dev)
 	pm_runtime_forbid(&dev->dev);
 	pm_runtime_get_noresume(&dev->dev);
 
+	i801_disable_host_notify(priv);
 	i801_del_mux(priv);
 	i2c_del_adapter(&priv->adapter);
 	i801_acpi_remove(priv);
@@ -1679,6 +1696,15 @@ static void i801_remove(struct pci_dev *dev)
 	 */
 }
 
+static void i801_shutdown(struct pci_dev *dev)
+{
+	struct i801_priv *priv = pci_get_drvdata(dev);
+
+	/* Restore config registers to avoid hard hang on some systems */
+	i801_disable_host_notify(priv);
+	pci_write_config_byte(dev, SMBHSTCFG, priv->original_hstcfg);
+}
+
 #ifdef CONFIG_PM
 static int i801_suspend(struct device *dev)
 {
@@ -1711,6 +1737,7 @@ static struct pci_driver i801_driver = {
 	.id_table	= i801_ids,
 	.probe		= i801_probe,
 	.remove		= i801_remove,
+	.shutdown	= i801_shutdown,
 	.driver		= {
 		.pm	= &i801_pm_ops,
 	},
diff --git a/drivers/i2c/busses/i2c-scmi.c b/drivers/i2c/busses/i2c-scmi.c
index dfc98df7b1b6..7aa7b9cb6203 100644
--- a/drivers/i2c/busses/i2c-scmi.c
+++ b/drivers/i2c/busses/i2c-scmi.c
@@ -18,6 +18,9 @@
 #define ACPI_SMBUS_HC_CLASS		"smbus"
 #define ACPI_SMBUS_HC_DEVICE_NAME	"cmi"
 
+/* SMBUS HID definition as supported by Microsoft Windows */
+#define ACPI_SMBUS_MS_HID		"SMB0001"
+
 ACPI_MODULE_NAME("smbus_cmi");
 
 struct smbus_methods_t {
@@ -51,6 +54,7 @@ static const struct smbus_methods_t ibm_smbus_methods = {
 static const struct acpi_device_id acpi_smbus_cmi_ids[] = {
 	{"SMBUS01", (kernel_ulong_t)&smbus_methods},
 	{ACPI_SMBUS_IBM_HID, (kernel_ulong_t)&ibm_smbus_methods},
+	{ACPI_SMBUS_MS_HID, (kernel_ulong_t)&smbus_methods},
 	{"", 0}
 };
 MODULE_DEVICE_TABLE(acpi, acpi_smbus_cmi_ids);
diff --git a/drivers/i2c/muxes/i2c-mux-reg.c b/drivers/i2c/muxes/i2c-mux-reg.c
index c6a90b4a9c62..91b10afc8c34 100644
--- a/drivers/i2c/muxes/i2c-mux-reg.c
+++ b/drivers/i2c/muxes/i2c-mux-reg.c
@@ -196,20 +196,25 @@ static int i2c_mux_reg_probe(struct platform_device *pdev)
 		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 		mux->data.reg_size = resource_size(res);
 		mux->data.reg = devm_ioremap_resource(&pdev->dev, res);
-		if (IS_ERR(mux->data.reg))
-			return PTR_ERR(mux->data.reg);
+		if (IS_ERR(mux->data.reg)) {
+			ret = PTR_ERR(mux->data.reg);
+			goto err_put_parent;
+		}
 	}
 
 	if (mux->data.reg_size != 4 && mux->data.reg_size != 2 &&
 	    mux->data.reg_size != 1) {
 		dev_err(&pdev->dev, "Invalid register size\n");
-		return -EINVAL;
+		ret = -EINVAL;
+		goto err_put_parent;
 	}
 
 	muxc = i2c_mux_alloc(parent, &pdev->dev, mux->data.n_values, 0, 0,
 			     i2c_mux_reg_select, NULL);
-	if (!muxc)
-		return -ENOMEM;
+	if (!muxc) {
+		ret = -ENOMEM;
+		goto err_put_parent;
+	}
 	muxc->priv = mux;
 
 	platform_set_drvdata(pdev, muxc);
@@ -235,6 +240,8 @@ static int i2c_mux_reg_probe(struct platform_device *pdev)
 
 add_adapter_failed:
 	i2c_mux_del_adapters(muxc);
+err_put_parent:
+	i2c_put_adapter(parent);
 
 	return ret;
 }