Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

Pull i2c fixes from Wolfram Sang:

 - a bigger fix for i801 to finally be able to be loaded on some
   machines again

 - smaller driver fixes

 - documentation update because of a renamed file

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: mux: reg: Provide of_match_table
  i2c: mux: refer to i2c-mux.txt
  i2c: octeon: Avoid printk after too long SMBUS message
  i2c: octeon: Missing AAK flag in case of I2C_M_RECV_LEN
  i2c: i801: Allow ACPI SystemIO OpRegion to conflict with PCI BAR

Documentation/devicetree/bindings/i2c/i2c-arb-gpio-challenge.txt

@@ -44,8 +44,8 @@ Required properties:
 - our-claim-gpio: The GPIO that we use to claim the bus.
 - their-claim-gpios: The GPIOs that the other sides use to claim the bus.
   Note that some implementations may only support a single other master.
-- Standard I2C mux properties. See mux.txt in this directory.
+- Standard I2C mux properties. See i2c-mux.txt in this directory.
-- Single I2C child bus node at reg 0. See mux.txt in this directory.
+- Single I2C child bus node at reg 0. See i2c-mux.txt in this directory.
 
 Optional properties:
 - slew-delay-us: microseconds to wait for a GPIO to go high. Default is 10 us.

Documentation/devicetree/bindings/i2c/i2c-demux-pinctrl.txt

@@ -27,7 +27,8 @@ Required properties:
 - i2c-bus-name: The name of this bus. Also needed as pinctrl-name for the I2C
 		parents.
 
-Furthermore, I2C mux properties and child nodes. See mux.txt in this directory.
+Furthermore, I2C mux properties and child nodes. See i2c-mux.txt in this
+directory.
 
 Example:
 

Documentation/devicetree/bindings/i2c/i2c-mux-gpio.txt

@@ -22,8 +22,8 @@ Required properties:
 - i2c-parent: The phandle of the I2C bus that this multiplexer's master-side
   port is connected to.
 - mux-gpios: list of gpios used to control the muxer
-* Standard I2C mux properties. See mux.txt in this directory.
+* Standard I2C mux properties. See i2c-mux.txt in this directory.
-* I2C child bus nodes. See mux.txt in this directory.
+* I2C child bus nodes. See i2c-mux.txt in this directory.
 
 Optional properties:
 - idle-state: value to set the muxer to when idle. When no value is
@@ -33,7 +33,7 @@ For each i2c child node, an I2C child bus will be created. They will
 be numbered based on their order in the device tree.
 
 Whenever an access is made to a device on a child bus, the value set
-in the revelant node's reg property will be output using the list of
+in the relevant node's reg property will be output using the list of
 GPIOs, the first in the list holding the least-significant value.
 
 If an idle state is defined, using the idle-state (optional) property,

Documentation/devicetree/bindings/i2c/i2c-mux-pinctrl.txt

@@ -28,9 +28,9 @@ Also required are:
 * Standard pinctrl properties that specify the pin mux state for each child
   bus. See ../pinctrl/pinctrl-bindings.txt.
 
-* Standard I2C mux properties. See mux.txt in this directory.
+* Standard I2C mux properties. See i2c-mux.txt in this directory.
 
-* I2C child bus nodes. See mux.txt in this directory.
+* I2C child bus nodes. See i2c-mux.txt in this directory.
 
 For each named state defined in the pinctrl-names property, an I2C child bus
 will be created. I2C child bus numbers are assigned based on the index into

Documentation/devicetree/bindings/i2c/i2c-mux-reg.txt

@@ -7,8 +7,8 @@ Required properties:
 - compatible: i2c-mux-reg
 - i2c-parent: The phandle of the I2C bus that this multiplexer's master-side
   port is connected to.
-* Standard I2C mux properties. See mux.txt in this directory.
+* Standard I2C mux properties. See i2c-mux.txt in this directory.
-* I2C child bus nodes. See mux.txt in this directory.
+* I2C child bus nodes. See i2c-mux.txt in this directory.
 
 Optional properties:
 - reg: this pair of <offset size> specifies the register to control the mux.
@@ -24,7 +24,7 @@ Optional properties:
   given, it defaults to the last value used.
 
 Whenever an access is made to a device on a child bus, the value set
-in the revelant node's reg property will be output to the register.
+in the relevant node's reg property will be output to the register.
 
 If an idle state is defined, using the idle-state (optional) property,
 whenever an access is not being made to a device on a child bus, the

drivers/i2c/busses/i2c-i801.c

@@ -245,6 +245,13 @@ struct i801_priv {
 	struct platform_device *mux_pdev;
 #endif
 	struct platform_device *tco_pdev;
+
+	/*
+	 * If set to true the host controller registers are reserved for
+	 * ACPI AML use. Protected by acpi_lock.
+	 */
+	bool acpi_reserved;
+	struct mutex acpi_lock;
 };
 
 #define FEATURE_SMBUS_PEC	(1 << 0)
@@ -718,6 +725,12 @@ static s32 i801_access(struct i2c_adapter *adap, u16 addr,
 	int ret = 0, xact = 0;
 	struct i801_priv *priv = i2c_get_adapdata(adap);
 
+	mutex_lock(&priv->acpi_lock);
+	if (priv->acpi_reserved) {
+		mutex_unlock(&priv->acpi_lock);
+		return -EBUSY;
+	}
+
 	pm_runtime_get_sync(&priv->pci_dev->dev);
 
 	hwpec = (priv->features & FEATURE_SMBUS_PEC) && (flags & I2C_CLIENT_PEC)
@@ -820,6 +833,7 @@ static s32 i801_access(struct i2c_adapter *adap, u16 addr,
 out:
 	pm_runtime_mark_last_busy(&priv->pci_dev->dev);
 	pm_runtime_put_autosuspend(&priv->pci_dev->dev);
+	mutex_unlock(&priv->acpi_lock);
 	return ret;
 }
 
@@ -1257,6 +1271,83 @@ static void i801_add_tco(struct i801_priv *priv)
 	priv->tco_pdev = pdev;
 }
 
+#ifdef CONFIG_ACPI
+static acpi_status
+i801_acpi_io_handler(u32 function, acpi_physical_address address, u32 bits,
+		     u64 *value, void *handler_context, void *region_context)
+{
+	struct i801_priv *priv = handler_context;
+	struct pci_dev *pdev = priv->pci_dev;
+	acpi_status status;
+
+	/*
+	 * Once BIOS AML code touches the OpRegion we warn and inhibit any
+	 * further access from the driver itself. This device is now owned
+	 * by the system firmware.
+	 */
+	mutex_lock(&priv->acpi_lock);
+
+	if (!priv->acpi_reserved) {
+		priv->acpi_reserved = true;
+
+		dev_warn(&pdev->dev, "BIOS is accessing SMBus registers\n");
+		dev_warn(&pdev->dev, "Driver SMBus register access inhibited\n");
+
+		/*
+		 * BIOS is accessing the host controller so prevent it from
+		 * suspending automatically from now on.
+		 */
+		pm_runtime_get_sync(&pdev->dev);
+	}
+
+	if ((function & ACPI_IO_MASK) == ACPI_READ)
+		status = acpi_os_read_port(address, (u32 *)value, bits);
+	else
+		status = acpi_os_write_port(address, (u32)*value, bits);
+
+	mutex_unlock(&priv->acpi_lock);
+
+	return status;
+}
+
+static int i801_acpi_probe(struct i801_priv *priv)
+{
+	struct acpi_device *adev;
+	acpi_status status;
+
+	adev = ACPI_COMPANION(&priv->pci_dev->dev);
+	if (adev) {
+		status = acpi_install_address_space_handler(adev->handle,
+				ACPI_ADR_SPACE_SYSTEM_IO, i801_acpi_io_handler,
+				NULL, priv);
+		if (ACPI_SUCCESS(status))
+			return 0;
+	}
+
+	return acpi_check_resource_conflict(&priv->pci_dev->resource[SMBBAR]);
+}
+
+static void i801_acpi_remove(struct i801_priv *priv)
+{
+	struct acpi_device *adev;
+
+	adev = ACPI_COMPANION(&priv->pci_dev->dev);
+	if (!adev)
+		return;
+
+	acpi_remove_address_space_handler(adev->handle,
+		ACPI_ADR_SPACE_SYSTEM_IO, i801_acpi_io_handler);
+
+	mutex_lock(&priv->acpi_lock);
+	if (priv->acpi_reserved)
+		pm_runtime_put(&priv->pci_dev->dev);
+	mutex_unlock(&priv->acpi_lock);
+}
+#else
+static inline int i801_acpi_probe(struct i801_priv *priv) { return 0; }
+static inline void i801_acpi_remove(struct i801_priv *priv) { }
+#endif
+
 static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
 {
 	unsigned char temp;
@@ -1274,6 +1365,7 @@ static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
 	priv->adapter.dev.parent = &dev->dev;
 	ACPI_COMPANION_SET(&priv->adapter.dev, ACPI_COMPANION(&dev->dev));
 	priv->adapter.retries = 3;
+	mutex_init(&priv->acpi_lock);
 
 	priv->pci_dev = dev;
 	switch (dev->device) {
@@ -1336,10 +1428,8 @@ static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
 		return -ENODEV;
 	}
 
-	err = acpi_check_resource_conflict(&dev->resource[SMBBAR]);
+	if (i801_acpi_probe(priv))
-	if (err) {
 		return -ENODEV;
-	}
 
 	err = pcim_iomap_regions(dev, 1 << SMBBAR,
 				 dev_driver_string(&dev->dev));
@@ -1348,6 +1438,7 @@ static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
 			"Failed to request SMBus region 0x%lx-0x%Lx\n",
 			priv->smba,
 			(unsigned long long)pci_resource_end(dev, SMBBAR));
+		i801_acpi_remove(priv);
 		return err;
 	}
 
@@ -1412,6 +1503,7 @@ static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
 	err = i2c_add_adapter(&priv->adapter);
 	if (err) {
 		dev_err(&dev->dev, "Failed to add SMBus adapter\n");
+		i801_acpi_remove(priv);
 		return err;
 	}
 
@@ -1438,6 +1530,7 @@ static void i801_remove(struct pci_dev *dev)
 
 	i801_del_mux(priv);
 	i2c_del_adapter(&priv->adapter);
+	i801_acpi_remove(priv);
 	pci_write_config_byte(dev, SMBHSTCFG, priv->original_hstcfg);
 
 	platform_device_unregister(priv->tco_pdev);

drivers/i2c/busses/i2c-octeon.c

@@ -934,8 +934,15 @@ static int octeon_i2c_read(struct octeon_i2c *i2c, int target,
 		return result;
 
 	for (i = 0; i < length; i++) {
-		/* for the last byte TWSI_CTL_AAK must not be set */
+		/*
-		if (i + 1 == length)
+		 * For the last byte to receive TWSI_CTL_AAK must not be set.
+		 *
+		 * A special case is I2C_M_RECV_LEN where we don't know the
+		 * additional length yet. If recv_len is set we assume we're
+		 * not reading the final byte and therefore need to set
+		 * TWSI_CTL_AAK.
+		 */
+		if ((i + 1 == length) && !(recv_len && i == 0))
 			final_read = true;
 
 		/* clear iflg to allow next event */
@@ -950,12 +957,8 @@ static int octeon_i2c_read(struct octeon_i2c *i2c, int target,
 
 		data[i] = octeon_i2c_data_read(i2c);
 		if (recv_len && i == 0) {
-			if (data[i] > I2C_SMBUS_BLOCK_MAX + 1) {
+			if (data[i] > I2C_SMBUS_BLOCK_MAX + 1)
-				dev_err(i2c->dev,
-					"%s: read len > I2C_SMBUS_BLOCK_MAX %d\n",
-					__func__, data[i]);
 				return -EPROTO;
-			}
 			length += data[i];
 		}
 

drivers/i2c/muxes/i2c-mux-reg.c

@@ -260,6 +260,7 @@ static struct platform_driver i2c_mux_reg_driver = {
 	.remove	= i2c_mux_reg_remove,
 	.driver	= {
 		.name	= "i2c-mux-reg",
+		.of_match_table = of_match_ptr(i2c_mux_reg_of_match),
 	},
 };