Merge branch 'i2c/for-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

Pull i2c updates from Wolfram Sang:

 - if a host can be a client, too, the I2C core can now use it to
   emulate SMBus HostNotify support (STM32 and R-Car added this so far)

 - also for client mode, a testunit has been added. It can create rare
   situations on the bus, so host controllers can be tested

 - a binding has been added to mark the bus as "single-master". This
   allows for better timeout detections

 - new driver for Mellanox Bluefield

 - massive refactoring of the Tegra driver

 - EEPROMs recognized by the at24 driver can now have custom names

 - rest is driver updates

* 'i2c/for-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (80 commits)
  Documentation: i2c: add testunit docs to index
  i2c: tegra: Improve driver module description
  i2c: tegra: Clean up whitespaces, newlines and indentation
  i2c: tegra: Clean up and improve comments
  i2c: tegra: Clean up printk messages
  i2c: tegra: Clean up variable names
  i2c: tegra: Improve formatting of variables
  i2c: tegra: Check errors for both positive and negative values
  i2c: tegra: Factor out hardware initialization into separate function
  i2c: tegra: Factor out register polling into separate function
  i2c: tegra: Factor out packet header setup from tegra_i2c_xfer_msg()
  i2c: tegra: Factor out error recovery from tegra_i2c_xfer_msg()
  i2c: tegra: Rename wait/poll functions
  i2c: tegra: Remove "dma" variable from tegra_i2c_xfer_msg()
  i2c: tegra: Remove redundant check in tegra_i2c_issue_bus_clear()
  i2c: tegra: Remove likely/unlikely from the code
  i2c: tegra: Remove outdated barrier()
  i2c: tegra: Clean up variable types
  i2c: tegra: Reorder location of functions in the code
  i2c: tegra: Clean up probe function
  ...

Documentation/devicetree/bindings/eeprom/at24.yaml

@@ -114,6 +114,9 @@ properties:
           - const: renesas,r1ex24128
           - const: atmel,24c128
 
+  label:
+    description: Descriptive name of the EEPROM.
+
   reg:
     maxItems: 1
 

Documentation/devicetree/bindings/i2c/i2c-imx-lpi2c.yaml

@@ -9,12 +9,18 @@ title: Freescale Low Power Inter IC (LPI2C) for i.MX
 maintainers:
   - Anson Huang <Anson.Huang@nxp.com>
 
+allOf:
+  - $ref: /schemas/i2c/i2c-controller.yaml#
+
 properties:
   compatible:
-    enum:
-      - fsl,imx7ulp-lpi2c
-      - fsl,imx8qxp-lpi2c
-      - fsl,imx8qm-lpi2c
+    oneOf:
+      - enum:
+          - fsl,imx7ulp-lpi2c
+          - fsl,imx8qm-lpi2c
+      - items:
+          - const: fsl,imx8qxp-lpi2c
+          - const: fsl,imx7ulp-lpi2c
 
   reg:
     maxItems: 1
@@ -22,23 +28,34 @@ properties:
   interrupts:
     maxItems: 1
 
+  assigned-clock-parents: true
+  assigned-clock-rates: true
+  assigned-clocks: true
+  clock-frequency: true
+
+  clock-names:
+    maxItems: 1
+
   clocks:
     maxItems: 1
 
+  power-domains:
+    maxItems: 1
+
 required:
   - compatible
   - reg
   - interrupts
   - clocks
 
-additionalProperties: false
+unevaluatedProperties: false
 
 examples:
   - |
     #include <dt-bindings/clock/imx7ulp-clock.h>
     #include <dt-bindings/interrupt-controller/arm-gic.h>
 
-    lpi2c7@40a50000 {
+    i2c@40a50000 {
         compatible = "fsl,imx7ulp-lpi2c";
         reg = <0x40A50000 0x10000>;
         interrupt-parent = <&intc>;

Documentation/devicetree/bindings/i2c/i2c-imx.yaml

@@ -9,6 +9,9 @@ title: Freescale Inter IC (I2C) and High Speed Inter IC (HS-I2C) for i.MX
 maintainers:
   - Wolfram Sang <wolfram@the-dreams.de>
 
+allOf:
+  - $ref: /schemas/i2c/i2c-controller.yaml#
+
 properties:
   compatible:
     oneOf:
@@ -18,6 +21,9 @@ properties:
       - items:
           - const: fsl,imx35-i2c
           - const: fsl,imx1-i2c
+      - items:
+          - const: fsl,imx7d-i2c
+          - const: fsl,imx21-i2c
       - items:
           - enum:
               - fsl,imx25-i2c
@@ -75,7 +81,7 @@ required:
   - interrupts
   - clocks
 
-additionalProperties: false
+unevaluatedProperties: false
 
 examples:
   - |

Documentation/devicetree/bindings/i2c/i2c.txt

@@ -87,6 +87,11 @@ wants to support one of the below features, it should adapt these bindings.
 	this information to detect a stalled bus more reliably, for example.
 	Can not be combined with 'multi-master'.
 
+- smbus
+	states that additional SMBus restrictions and features apply to this bus.
+	Examples of features are SMBusHostNotify and SMBusAlert. Examples of
+	restrictions are more reserved addresses and timeout definitions.
+
 Required properties (per child device)
 --------------------------------------
 

Documentation/devicetree/bindings/i2c/ingenic,i2c.yaml

@@ -17,9 +17,13 @@ properties:
     pattern: "^i2c@[0-9a-f]+$"
 
   compatible:
-    enum:
-      - ingenic,jz4780-i2c
-      - ingenic,x1000-i2c
+    oneOf:
+      - enum:
+        - ingenic,jz4770-i2c
+        - ingenic,x1000-i2c
+      - items:
+        - const: ingenic,jz4780-i2c
+        - const: ingenic,jz4770-i2c
 
   reg:
     maxItems: 1
@@ -60,7 +64,7 @@ examples:
     #include <dt-bindings/dma/jz4780-dma.h>
     #include <dt-bindings/interrupt-controller/irq.h>
     i2c@10054000 {
-      compatible = "ingenic,jz4780-i2c";
+      compatible = "ingenic,jz4780-i2c", "ingenic,jz4770-i2c";
       #address-cells = <1>;
       #size-cells = <0>;
       reg = <0x10054000 0x1000>;

Documentation/devicetree/bindings/i2c/mellanox,i2c-mlxbf.txt

+Device tree configuration for the Mellanox I2C SMBus on BlueField SoCs
+
+Required Properties:
+
+- compatible : should be "mellanox,i2c-mlxbf1" or "mellanox,i2c-mlxbf2".
+
+- reg : address offset and length of the device registers. The
+	registers consist of the following set of resources:
+		1) Smbus block registers.
+		2) Cause master registers.
+		3) Cause slave registers.
+		4) Cause coalesce registers (if compatible isn't set
+		   to "mellanox,i2c-mlxbf1").
+
+- interrupts : interrupt number.
+
+Optional Properties:
+
+- clock-frequency : bus frequency used to configure timing registers;
+			allowed values are 100000, 400000 and 1000000;
+			those are expressed in Hz. Default is 100000.
+
+Example:
+
+i2c@2804000 {
+	compatible = "mellanox,i2c-mlxbf1";
+	reg =	<0x02804000 0x800>,
+		<0x02801200 0x020>,
+		<0x02801260 0x020>;
+	interrupts = <57>;
+	clock-frequency = <100000>;
+};
+
+i2c@2808800 {
+	compatible = "mellanox,i2c-mlxbf2";
+	reg =	<0x02808800 0x600>,
+	        <0x02808e00 0x020>,
+		<0x02808e20 0x020>,
+		<0x02808e40 0x010>;
+	interrupts = <57>;
+	clock-frequency = <400000>;
+};

Documentation/i2c/busses/i2c-i801.rst

@@ -44,6 +44,7 @@ Supported adapters:
   * Intel Tiger Lake (PCH)
   * Intel Jasper Lake (SOC)
   * Intel Emmitsburg (PCH)
+  * Intel Alder Lake (PCH)
 
    Datasheets: Publicly available at the Intel website
 

Documentation/i2c/index.rst

@@ -47,6 +47,7 @@ Slave I2C
 
    slave-interface
    slave-eeprom-backend
+   slave-testunit-backend
 
 Advanced topics
 ===============

Documentation/i2c/slave-testunit-backend.rst

+.. SPDX-License-Identifier: GPL-2.0
+
+================================
+Linux I2C slave testunit backend
+================================
+
+by Wolfram Sang <wsa@sang-engineering.com> in 2020
+
+This backend can be used to trigger test cases for I2C bus masters which
+require a remote device with certain capabilities (and which are usually not so
+easy to obtain). Examples include multi-master testing, and SMBus Host Notify
+testing. For some tests, the I2C slave controller must be able to switch
+between master and slave mode because it needs to send data, too.
+
+Note that this is a device for testing and debugging. It should not be enabled
+in a production build. And while there is some versioning and we try hard to
+keep backward compatibility, there is no stable ABI guaranteed!
+
+Instantiating the device is regular. Example for bus 0, address 0x30:
+
+# echo "slave-testunit 0x1030" > /sys/bus/i2c/devices/i2c-0/new_device
+
+After that, you will have a write-only device listening. Reads will just return
+an 8-bit version number of the testunit. When writing, the device consists of 4
+8-bit registers and all must be written to start a testcase, i.e. you must
+always write 4 bytes to the device. The registers are:
+
+0x00 CMD   - which test to trigger
+0x01 DATAL - configuration byte 1 for the test
+0x02 DATAH - configuration byte 2 for the test
+0x03 DELAY - delay in n * 10ms until test is started
+
+Using 'i2cset' from the i2c-tools package, the generic command looks like:
+
+# i2cset -y <bus_num> <testunit_address> <CMD> <DATAL> <DATAH> <DELAY> i
+
+DELAY is a generic parameter which will delay the execution of the test in CMD.
+While a command is running (including the delay), new commands will not be
+acknowledged. You need to wait until the old one is completed.
+
+The commands are described in the following section. An invalid command will
+result in the transfer not being acknowledged.
+
+Commands
+--------
+
+0x00 NOOP (reserved for future use)
+
+0x01 READ_BYTES (also needs master mode)
+   DATAL - address to read data from (lower 7 bits, highest bit currently unused)
+   DATAH - number of bytes to read
+
+This is useful to test if your bus master driver is handling multi-master
+correctly. You can trigger the testunit to read bytes from another device on
+the bus. If the bus master under test also wants to access the bus at the same
+time, the bus will be busy. Example to read 128 bytes from device 0x50 after
+50ms of delay:
+
+# i2cset -y 0 0x30 0x01 0x50 0x80 0x05 i
+
+0x02 SMBUS_HOST_NOTIFY (also needs master mode)
+   DATAL - low byte of the status word to send
+   DATAH - high byte of the status word to send
+
+This test will send an SMBUS_HOST_NOTIFY message to the host. Note that the
+status word is currently ignored in the Linux Kernel. Example to send a
+notification after 10ms:
+
+# i2cset -y 0 0x30 0x02 0x42 0x64 0x01 i

MAINTAINERS

@@ -11159,6 +11159,12 @@ W:	http://www.melfas.com
 F:	Documentation/devicetree/bindings/input/touchscreen/melfas_mip4.txt
 F:	drivers/input/touchscreen/melfas_mip4.c
 
+MELLANOX BLUEFIELD I2C DRIVER
+M:	Khalil Blaiech <kblaiech@mellanox.com>
+L:	linux-i2c@vger.kernel.org
+S:	Supported
+F:	drivers/i2c/busses/i2c-mlxbf.c
+
 MELLANOX ETHERNET DRIVER (mlx4_en)
 M:	Tariq Toukan <tariqt@nvidia.com>
 L:	netdev@vger.kernel.org

drivers/i2c/Kconfig

@@ -101,7 +101,6 @@ source "drivers/i2c/busses/Kconfig"
 config I2C_STUB
 	tristate "I2C/SMBus Test Stub"
 	depends on m
-	default 'n'
 	help
 	  This module may be useful to developers of SMBus client drivers,
 	  especially for certain kinds of sensor chips.
@@ -126,6 +125,14 @@ config I2C_SLAVE_EEPROM
 	  This backend makes Linux behave like an I2C EEPROM. Please read
 	  Documentation/i2c/slave-eeprom-backend.rst for further details.
 
+config I2C_SLAVE_TESTUNIT
+	tristate "I2C eeprom testunit driver"
+	help
+	  This backend can be used to trigger test cases for I2C bus masters
+	  which require a remote device with certain capabilities, e.g.
+	  multi-master, SMBus Host Notify, etc. Please read
+	  Documentation/i2c/slave-testunit-backend.rst for further details.
+
 endif
 
 config I2C_DEBUG_CORE

drivers/i2c/Makefile

@@ -16,5 +16,6 @@ obj-$(CONFIG_I2C_MUX)		+= i2c-mux.o
 obj-y				+= algos/ busses/ muxes/
 obj-$(CONFIG_I2C_STUB)		+= i2c-stub.o
 obj-$(CONFIG_I2C_SLAVE_EEPROM)	+= i2c-slave-eeprom.o
+obj-$(CONFIG_I2C_SLAVE_TESTUNIT)	+= i2c-slave-testunit.o
 
 ccflags-$(CONFIG_I2C_DEBUG_CORE) := -DDEBUG

drivers/i2c/busses/Kconfig

@@ -147,6 +147,7 @@ config I2C_I801
 	    Tiger Lake (PCH)
 	    Jasper Lake (SOC)
 	    Emmitsburg (PCH)
+	    Alder Lake (PCH)
 
 	  This driver can also be built as a module.  If so, the module
 	  will be called i2c-i801.
@@ -730,6 +731,19 @@ config I2C_LPC2K
 	  This driver can also be built as a module.  If so, the module
 	  will be called i2c-lpc2k.
 
+config I2C_MLXBF
+        tristate "Mellanox BlueField I2C controller"
+        depends on ARM64
+        help
+          Enabling this option will add I2C SMBus support for Mellanox BlueField
+          system.
+
+          This driver can also be built as a module. If so, the module will be
+          called i2c-mlxbf.
+
+          This driver implements an I2C SMBus host controller and enables both
+          master and slave functions.
+
 config I2C_MESON
 	tristate "Amlogic Meson I2C controller"
 	depends on ARCH_MESON || COMPILE_TEST
@@ -840,7 +854,6 @@ config I2C_PASEMI
 config I2C_PCA_PLATFORM
 	tristate "PCA9564/PCA9665 as platform device"
 	select I2C_ALGOPCA
-	default n
 	help
 	  This driver supports a memory mapped Philips PCA9564/PCA9665
 	  parallel bus to I2C bus controller.
@@ -1026,6 +1039,7 @@ config I2C_STM32F7
 	tristate "STMicroelectronics STM32F7 I2C support"
 	depends on ARCH_STM32 || COMPILE_TEST
 	select I2C_SLAVE
+	select I2C_SMBUS
 	help
 	  Enable this option to add support for STM32 I2C controller embedded
 	  in STM32F7 SoCs.
@@ -1181,6 +1195,8 @@ config I2C_RCAR
 	tristate "Renesas R-Car I2C Controller"
 	depends on ARCH_RENESAS || COMPILE_TEST
 	select I2C_SLAVE
+	select I2C_SMBUS
+	select RESET_CONTROLLER if ARCH_RCAR_GEN3
 	help
 	  If you say yes to this option, support will be included for the
 	  R-Car I2C controller.
@@ -1240,7 +1256,6 @@ config I2C_TAOS_EVM
 	depends on TTY
 	select SERIO
 	select SERIO_SERPORT
-	default n
 	help
 	  This supports TAOS evaluation modules on serial port. In order to
 	  use this driver, you will need the inputattach tool, which is part
@@ -1324,7 +1339,6 @@ config I2C_PCA_ISA
 	tristate "PCA9564/PCA9665 on an ISA bus"
 	depends on ISA
 	select I2C_ALGOPCA
-	default n
 	help
 	  This driver supports ISA boards using the Philips PCA9564/PCA9665
 	  parallel bus to I2C bus controller.

drivers/i2c/busses/Makefile

@@ -140,6 +140,7 @@ obj-$(CONFIG_I2C_BRCMSTB)	+= i2c-brcmstb.o
 obj-$(CONFIG_I2C_CROS_EC_TUNNEL)	+= i2c-cros-ec-tunnel.o
 obj-$(CONFIG_I2C_ELEKTOR)	+= i2c-elektor.o
 obj-$(CONFIG_I2C_ICY)		+= i2c-icy.o
+obj-$(CONFIG_I2C_MLXBF)		+= i2c-mlxbf.o
 obj-$(CONFIG_I2C_MLXCPLD)	+= i2c-mlxcpld.o
 obj-$(CONFIG_I2C_OPAL)		+= i2c-opal.o
 obj-$(CONFIG_I2C_PCA_ISA)	+= i2c-pca-isa.o

drivers/i2c/busses/i2c-amd-mp2-plat.c

@@ -155,7 +155,7 @@ static int i2c_amd_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
 	struct amd_i2c_dev *i2c_dev = i2c_get_adapdata(adap);
 	int i;
 	struct i2c_msg *pmsg;
-	int err;
+	int err = 0;
 
 	/* the adapter might have been deleted while waiting for the bus lock */
 	if (unlikely(!i2c_dev->common.mp2_dev))

drivers/i2c/busses/i2c-bcm2835.c

@@ -421,11 +421,9 @@ static int bcm2835_i2c_probe(struct platform_device *pdev)
 		return PTR_ERR(i2c_dev->regs);
 
 	mclk = devm_clk_get(&pdev->dev, NULL);
-	if (IS_ERR(mclk)) {
-		if (PTR_ERR(mclk) != -EPROBE_DEFER)
-			dev_err(&pdev->dev, "Could not get clock\n");
-		return PTR_ERR(mclk);
-	}
+	if (IS_ERR(mclk))
+		return dev_err_probe(&pdev->dev, PTR_ERR(mclk),
+				     "Could not get clock\n");
 
 	i2c_dev->bus_clk = bcm2835_i2c_register_div(&pdev->dev, mclk, i2c_dev);
 

drivers/i2c/busses/i2c-efm32.c

@@ -332,21 +332,15 @@ static int efm32_i2c_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	if (!res) {
-		dev_err(&pdev->dev, "failed to determine base address\n");
-		return -ENODEV;
-	}
+	ddata->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
+	if (IS_ERR(ddata->base))
+		return PTR_ERR(ddata->base);
 
 	if (resource_size(res) < 0x42) {
 		dev_err(&pdev->dev, "memory resource too small\n");
 		return -EINVAL;
 	}
 
-	ddata->base = devm_ioremap_resource(&pdev->dev, res);
-	if (IS_ERR(ddata->base))
-		return PTR_ERR(ddata->base);
-
 	ret = platform_get_irq(pdev, 0);
 	if (ret <= 0) {
 		if (!ret)

drivers/i2c/busses/i2c-i801.c

@@ -71,6 +71,7 @@
  * Tiger Lake-H (PCH)		0x43a3	32	hard	yes	yes	yes
  * Jasper Lake (SOC)		0x4da3	32	hard	yes	yes	yes
  * Comet Lake-V (PCH)		0xa3a3	32	hard	yes	yes	yes
+ * Alder Lake-S (PCH)		0x7aa3	32	hard	yes	yes	yes
  *
  * Features supported by this driver:
  * Software PEC				no
@@ -228,6 +229,7 @@
 #define PCI_DEVICE_ID_INTEL_ELKHART_LAKE_SMBUS		0x4b23
 #define PCI_DEVICE_ID_INTEL_JASPER_LAKE_SMBUS		0x4da3
 #define PCI_DEVICE_ID_INTEL_BROXTON_SMBUS		0x5ad4
+#define PCI_DEVICE_ID_INTEL_ALDER_LAKE_S_SMBUS		0x7aa3
 #define PCI_DEVICE_ID_INTEL_LYNXPOINT_SMBUS		0x8c22
 #define PCI_DEVICE_ID_INTEL_WILDCATPOINT_SMBUS		0x8ca2
 #define PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS		0x8d22
@@ -1081,6 +1083,7 @@ static const struct pci_device_id i801_ids[] = {
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_TIGERLAKE_LP_SMBUS) },
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_TIGERLAKE_H_SMBUS) },
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_JASPER_LAKE_SMBUS) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ALDER_LAKE_S_SMBUS) },
 	{ 0, }
 };
 
@@ -1274,6 +1277,7 @@ static const struct {
 	/*
 	 * Additional individual entries were added after verification.
 	 */
+	{ "Latitude 5480",      0x29 },
 	{ "Vostro V131",        0x1d },
 };
 
@@ -1767,6 +1771,7 @@ static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
 	case PCI_DEVICE_ID_INTEL_TIGERLAKE_H_SMBUS:
 	case PCI_DEVICE_ID_INTEL_JASPER_LAKE_SMBUS:
 	case PCI_DEVICE_ID_INTEL_EBG_SMBUS:
+	case PCI_DEVICE_ID_INTEL_ALDER_LAKE_S_SMBUS:
 		priv->features |= FEATURE_BLOCK_PROC;
 		priv->features |= FEATURE_I2C_BLOCK_READ;
 		priv->features |= FEATURE_IRQ;

drivers/i2c/busses/i2c-imx.c

@@ -1159,11 +1159,9 @@ static int i2c_imx_probe(struct platform_device *pdev)
 
 	/* Get I2C clock */
 	i2c_imx->clk = devm_clk_get(&pdev->dev, NULL);
-	if (IS_ERR(i2c_imx->clk)) {
-		if (PTR_ERR(i2c_imx->clk) != -EPROBE_DEFER)
-			dev_err(&pdev->dev, "can't get I2C clock\n");
-		return PTR_ERR(i2c_imx->clk);
-	}
+	if (IS_ERR(i2c_imx->clk))
+		return dev_err_probe(&pdev->dev, PTR_ERR(i2c_imx->clk),
+				     "can't get I2C clock\n");
 
 	ret = clk_prepare_enable(i2c_imx->clk);
 	if (ret) {
@@ -1171,14 +1169,6 @@ static int i2c_imx_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	/* Request IRQ */
-	ret = devm_request_irq(&pdev->dev, irq, i2c_imx_isr, IRQF_SHARED,
-				pdev->name, i2c_imx);
-	if (ret) {
-		dev_err(&pdev->dev, "can't claim irq %d\n", irq);
-		goto clk_disable;
-	}
-
 	/* Init queue */
 	init_waitqueue_head(&i2c_imx->queue);
 
@@ -1197,6 +1187,14 @@ static int i2c_imx_probe(struct platform_device *pdev)
 	if (ret < 0)
 		goto rpm_disable;
 
+	/* Request IRQ */
+	ret = request_threaded_irq(irq, i2c_imx_isr, NULL, IRQF_SHARED,
+				   pdev->name, i2c_imx);
+	if (ret) {
+		dev_err(&pdev->dev, "can't claim irq %d\n", irq);
+		goto rpm_disable;
+	}
+
 	/* Set up clock divider */
 	i2c_imx->bitrate = I2C_MAX_STANDARD_MODE_FREQ;
 	ret = of_property_read_u32(pdev->dev.of_node,
@@ -1239,13 +1237,12 @@ static int i2c_imx_probe(struct platform_device *pdev)
 
 clk_notifier_unregister:
 	clk_notifier_unregister(i2c_imx->clk, &i2c_imx->clk_change_nb);
+	free_irq(irq, i2c_imx);
 rpm_disable:
 	pm_runtime_put_noidle(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 	pm_runtime_set_suspended(&pdev->dev);
 	pm_runtime_dont_use_autosuspend(&pdev->dev);
-
-clk_disable:
 	clk_disable_unprepare(i2c_imx->clk);
 	return ret;
 }
@@ -1253,7 +1250,7 @@ static int i2c_imx_probe(struct platform_device *pdev)
 static int i2c_imx_remove(struct platform_device *pdev)
 {
 	struct imx_i2c_struct *i2c_imx = platform_get_drvdata(pdev);
-	int ret;
+	int irq, ret;
 
 	ret = pm_runtime_get_sync(&pdev->dev);
 	if (ret < 0)
@@ -1273,6 +1270,9 @@ static int i2c_imx_remove(struct platform_device *pdev)
 	imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2SR);
 
 	clk_notifier_unregister(i2c_imx->clk, &i2c_imx->clk_change_nb);
+	irq = platform_get_irq(pdev, 0);
+	if (irq >= 0)
+		free_irq(irq, i2c_imx);
 	clk_disable_unprepare(i2c_imx->clk);
 
 	pm_runtime_put_noidle(&pdev->dev);

drivers/i2c/busses/i2c-ismt.c

@@ -77,6 +77,7 @@
 #define PCI_DEVICE_ID_INTEL_S1200_SMT1	0x0c5a
 #define PCI_DEVICE_ID_INTEL_CDF_SMT	0x18ac
 #define PCI_DEVICE_ID_INTEL_DNV_SMT	0x19ac
+#define PCI_DEVICE_ID_INTEL_EBG_SMT	0x1bff
 #define PCI_DEVICE_ID_INTEL_AVOTON_SMT	0x1f15
 
 #define ISMT_DESC_ENTRIES	2	/* number of descriptor entries */
@@ -176,14 +177,12 @@ struct ismt_priv {
 	u8 buffer[I2C_SMBUS_BLOCK_MAX + 16];	/* temp R/W data buffer */
 };
 
-/**
- * ismt_ids - PCI device IDs supported by this driver
- */
 static const struct pci_device_id ismt_ids[] = {
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_S1200_SMT0) },
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_S1200_SMT1) },
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_CDF_SMT) },
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_DNV_SMT) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_EBG_SMT) },
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_AVOTON_SMT) },
 	{ 0, }
 };
@@ -197,6 +196,8 @@ MODULE_PARM_DESC(bus_speed, "Bus Speed in kHz (0 = BIOS default)");
 
 /**
  * __ismt_desc_dump() - dump the contents of a specific descriptor
+ * @dev: the iSMT device
+ * @desc: the iSMT hardware descriptor
  */
 static void __ismt_desc_dump(struct device *dev, const struct ismt_desc *desc)
 {
@@ -628,11 +629,6 @@ static u32 ismt_func(struct i2c_adapter *adap)
 	       I2C_FUNC_SMBUS_PEC;
 }
 
-/**
- * smbus_algorithm - the adapter algorithm and supported functionality
- * @smbus_xfer: the adapter algorithm
- * @functionality: functionality supported by the adapter
- */
 static const struct i2c_algorithm smbus_algorithm = {
 	.smbus_xfer	= ismt_access,
 	.functionality	= ismt_func,

drivers/i2c/busses/i2c-jz4780.c

@@ -752,6 +752,7 @@ static const struct ingenic_i2c_config x1000_i2c_config = {
 };
 
 static const struct of_device_id jz4780_i2c_of_matches[] = {
+	{ .compatible = "ingenic,jz4770-i2c", .data = &jz4780_i2c_config },
 	{ .compatible = "ingenic,jz4780-i2c", .data = &jz4780_i2c_config },
 	{ .compatible = "ingenic,x1000-i2c", .data = &x1000_i2c_config },
 	{ /* sentinel */ }
@@ -856,7 +857,7 @@ static struct platform_driver jz4780_i2c_driver = {
 	.remove		= jz4780_i2c_remove,
 	.driver		= {
 		.name	= "jz4780-i2c",
-		.of_match_table = of_match_ptr(jz4780_i2c_of_matches),
+		.of_match_table = jz4780_i2c_of_matches,
 	},
 };
 

drivers/i2c/busses/i2c-mv64xxx.c

@@ -496,11 +496,10 @@ static irqreturn_t
 mv64xxx_i2c_intr(int irq, void *dev_id)
 {
 	struct mv64xxx_i2c_data	*drv_data = dev_id;
-	unsigned long	flags;
 	u32		status;
 	irqreturn_t	rc = IRQ_NONE;
 
-	spin_lock_irqsave(&drv_data->lock, flags);
+	spin_lock(&drv_data->lock);
 
 	if (drv_data->offload_enabled)
 		rc = mv64xxx_i2c_intr_offload(drv_data);
@@ -517,7 +516,7 @@ mv64xxx_i2c_intr(int irq, void *dev_id)
 
 		rc = IRQ_HANDLED;
 	}
-	spin_unlock_irqrestore(&drv_data->lock, flags);
+	spin_unlock(&drv_data->lock);
 
 	return rc;
 }

drivers/i2c/busses/i2c-nvidia-gpu.c

@@ -125,8 +125,7 @@ static int gpu_i2c_read(struct gpu_i2c_dev *i2cd, u8 *data, u16 len)
 		put_unaligned_be16(val, data);
 		break;
 	case 3:
-		put_unaligned_be16(val >> 8, data);
-		data[2] = val;
+		put_unaligned_be24(val, data);
 		break;
 	case 4:
 		put_unaligned_be32(val, data);

drivers/i2c/busses/i2c-owl.c

@@ -165,10 +165,9 @@ static irqreturn_t owl_i2c_interrupt(int irq, void *_dev)
 {
 	struct owl_i2c_dev *i2c_dev = _dev;
 	struct i2c_msg *msg = i2c_dev->msg;
-	unsigned long flags;
 	unsigned int stat, fifostat;
 
-	spin_lock_irqsave(&i2c_dev->lock, flags);
+	spin_lock(&i2c_dev->lock);
 
 	i2c_dev->err = 0;
 
@@ -214,7 +213,7 @@ static irqreturn_t owl_i2c_interrupt(int irq, void *_dev)
 			   OWL_I2C_STAT_IRQP, true);
 
 	complete_all(&i2c_dev->msg_complete);
-	spin_unlock_irqrestore(&i2c_dev->lock, flags);
+	spin_unlock(&i2c_dev->lock);
 
 	return IRQ_HANDLED;
 }

drivers/i2c/busses/i2c-qcom-geni.c

@@ -210,9 +210,8 @@ static irqreturn_t geni_i2c_irq(int irq, void *dev)
 	u32 dma;
 	u32 val;
 	struct i2c_msg *cur;
-	unsigned long flags;
 
-	spin_lock_irqsave(&gi2c->lock, flags);
+	spin_lock(&gi2c->lock);
 	m_stat = readl_relaxed(base + SE_GENI_M_IRQ_STATUS);
 	rx_st = readl_relaxed(base + SE_GENI_RX_FIFO_STATUS);
 	dm_tx_st = readl_relaxed(base + SE_DMA_TX_IRQ_STAT);
@@ -294,7 +293,7 @@ static irqreturn_t geni_i2c_irq(int irq, void *dev)
 	    dm_rx_st & RX_DMA_DONE || dm_rx_st & RX_RESET_DONE)
 		complete(&gi2c->done);
 
-	spin_unlock_irqrestore(&gi2c->lock, flags);
+	spin_unlock(&gi2c->lock);
 
 	return IRQ_HANDLED;
 }

drivers/i2c/busses/i2c-rcar.c

@@ -19,7 +19,9 @@
 #include <linux/err.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
+#include <linux/iopoll.h>
 #include <linux/i2c.h>
+#include <linux/i2c-smbus.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/of_device.h>
@@ -105,10 +107,11 @@
 #define ID_ARBLOST	(1 << 3)
 #define ID_NACK		(1 << 4)
 /* persistent flags */
+#define ID_P_HOST_NOTIFY	BIT(28)
 #define ID_P_REP_AFTER_RD	BIT(29)
 #define ID_P_NO_RXDMA		BIT(30) /* HW forbids RXDMA sometimes */
 #define ID_P_PM_BLOCKED		BIT(31)
-#define ID_P_MASK		GENMASK(31, 29)
+#define ID_P_MASK		GENMASK(31, 28)
 
 enum rcar_i2c_type {
 	I2C_RCAR_GEN1,
@@ -140,14 +143,13 @@ struct rcar_i2c_priv {
 
 	struct reset_control *rstc;
 	int irq;
+
+	struct i2c_client *host_notify_client;
 };
 
 #define rcar_i2c_priv_to_dev(p)		((p)->adap.dev.parent)
 #define rcar_i2c_is_recv(p)		((p)->msg->flags & I2C_M_RD)
 
-#define LOOP_TIMEOUT	1024
-
-
 static void rcar_i2c_write(struct rcar_i2c_priv *priv, int reg, u32 val)
 {
 	writel(val, priv->io + reg);
@@ -221,18 +223,18 @@ static void rcar_i2c_init(struct rcar_i2c_priv *priv)
 
 static int rcar_i2c_bus_barrier(struct rcar_i2c_priv *priv)
 {
-	int i;
+	int ret;
+	u32 val;
 
-	for (i = 0; i < LOOP_TIMEOUT; i++) {
-		/* make sure that bus is not busy */
-		if (!(rcar_i2c_read(priv, ICMCR) & FSDA))
-			return 0;
-		udelay(1);
+	ret = readl_poll_timeout(priv->io + ICMCR, val, !(val & FSDA), 10,
+				 priv->adap.timeout);
+	if (ret) {
+		/* Waiting did not help, try to recover */
+		priv->recovery_icmcr = MDBS | OBPC | FSDA | FSCL;
+		ret = i2c_recover_bus(&priv->adap);
 	}
 
-	/* Waiting did not help, try to recover */
-	priv->recovery_icmcr = MDBS | OBPC | FSDA | FSCL;
-	return i2c_recover_bus(&priv->adap);
+	return ret;
 }
 
 static int rcar_i2c_clock_calculate(struct rcar_i2c_priv *priv)
@@ -760,20 +762,14 @@ static void rcar_i2c_release_dma(struct rcar_i2c_priv *priv)
 /* I2C is a special case, we need to poll the status of a reset */
 static int rcar_i2c_do_reset(struct rcar_i2c_priv *priv)
 {
-	int i, ret;
+	int ret;
 
 	ret = reset_control_reset(priv->rstc);
 	if (ret)
 		return ret;
 
-	for (i = 0; i < LOOP_TIMEOUT; i++) {
-		ret = reset_control_status(priv->rstc);
-		if (ret == 0)
-			return 0;
-		udelay(1);
-	}
-
-	return -ETIMEDOUT;
+	return read_poll_timeout_atomic(reset_control_status, ret, ret == 0, 1,
+					100, false, priv->rstc);
 }
 
 static int rcar_i2c_master_xfer(struct i2c_adapter *adap,
@@ -884,14 +880,21 @@ static int rcar_unreg_slave(struct i2c_client *slave)
 
 static u32 rcar_i2c_func(struct i2c_adapter *adap)
 {
+	struct rcar_i2c_priv *priv = i2c_get_adapdata(adap);
+
 	/*
 	 * This HW can't do:
 	 * I2C_SMBUS_QUICK (setting FSB during START didn't work)
 	 * I2C_M_NOSTART (automatically sends address after START)
 	 * I2C_M_IGNORE_NAK (automatically sends STOP after NAK)
 	 */
-	return I2C_FUNC_I2C | I2C_FUNC_SLAVE |
-		(I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
+	u32 func = I2C_FUNC_I2C | I2C_FUNC_SLAVE |
+		   (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
+
+	if (priv->flags & ID_P_HOST_NOTIFY)
+		func |= I2C_FUNC_SMBUS_HOST_NOTIFY;
+
+	return func;
 }
 
 static const struct i2c_algorithm rcar_i2c_algo = {
@@ -991,6 +994,8 @@ static int rcar_i2c_probe(struct platform_device *pdev)
 	else
 		pm_runtime_put(dev);
 
+	if (of_property_read_bool(dev->of_node, "smbus"))
+		priv->flags |= ID_P_HOST_NOTIFY;
 
 	priv->irq = platform_get_irq(pdev, 0);
 	ret = devm_request_irq(dev, priv->irq, rcar_i2c_irq, 0, dev_name(dev), priv);
@@ -1005,10 +1010,20 @@ static int rcar_i2c_probe(struct platform_device *pdev)
 	if (ret < 0)
 		goto out_pm_disable;
 
+	if (priv->flags & ID_P_HOST_NOTIFY) {
+		priv->host_notify_client = i2c_new_slave_host_notify_device(adap);
+		if (IS_ERR(priv->host_notify_client)) {
+			ret = PTR_ERR(priv->host_notify_client);
+			goto out_del_device;
+		}
+	}
+
 	dev_info(dev, "probed\n");
 
 	return 0;
 
+ out_del_device:
+	i2c_del_adapter(&priv->adap);
  out_pm_put:
 	pm_runtime_put(dev);
  out_pm_disable:
@@ -1021,6 +1036,8 @@ static int rcar_i2c_remove(struct platform_device *pdev)
 	struct rcar_i2c_priv *priv = platform_get_drvdata(pdev);
 	struct device *dev = &pdev->dev;
 
+	if (priv->host_notify_client)
+		i2c_free_slave_host_notify_device(priv->host_notify_client);
 	i2c_del_adapter(&priv->adap);
 	rcar_i2c_release_dma(priv);
 	if (priv->flags & ID_P_PM_BLOCKED)

drivers/i2c/busses/i2c-rk3x.c

@@ -1312,18 +1312,13 @@ static int rk3x_i2c_probe(struct platform_device *pdev)
 		i2c->pclk = devm_clk_get(&pdev->dev, "pclk");
 	}
 
-	if (IS_ERR(i2c->clk)) {
-		ret = PTR_ERR(i2c->clk);
-		if (ret != -EPROBE_DEFER)
-			dev_err(&pdev->dev, "Can't get bus clk: %d\n", ret);
-		return ret;
-	}
-	if (IS_ERR(i2c->pclk)) {
-		ret = PTR_ERR(i2c->pclk);
-		if (ret != -EPROBE_DEFER)
-			dev_err(&pdev->dev, "Can't get periph clk: %d\n", ret);
-		return ret;
-	}
+	if (IS_ERR(i2c->clk))
+		return dev_err_probe(&pdev->dev, PTR_ERR(i2c->clk),
+				     "Can't get bus clk\n");
+
+	if (IS_ERR(i2c->pclk))
+		return dev_err_probe(&pdev->dev, PTR_ERR(i2c->pclk),
+				     "Can't get periph clk\n");
 
 	ret = clk_prepare(i2c->clk);
 	if (ret < 0) {

drivers/i2c/busses/i2c-stm32.c

@@ -26,8 +26,9 @@ struct stm32_i2c_dma *stm32_i2c_dma_request(struct device *dev,
 	dma->chan_tx = dma_request_chan(dev, "tx");
 	if (IS_ERR(dma->chan_tx)) {
 		ret = PTR_ERR(dma->chan_tx);
-		if (ret != -EPROBE_DEFER)
-			dev_err(dev, "can't request DMA tx channel\n");
+		if (ret != -ENODEV)
+			ret = dev_err_probe(dev, ret,
+					    "can't request DMA tx channel\n");
 		goto fail_al;
 	}
 
@@ -46,8 +47,9 @@ struct stm32_i2c_dma *stm32_i2c_dma_request(struct device *dev,
 	dma->chan_rx = dma_request_chan(dev, "rx");
 	if (IS_ERR(dma->chan_rx)) {
 		ret = PTR_ERR(dma->chan_rx);
-		if (ret != -EPROBE_DEFER)
-			dev_err(dev, "can't request DMA rx channel\n");
+		if (ret != -ENODEV)
+			ret = dev_err_probe(dev, ret,
+					    "can't request DMA rx channel\n");
 
 		goto fail_tx;
 	}
@@ -76,8 +78,6 @@ struct stm32_i2c_dma *stm32_i2c_dma_request(struct device *dev,
 	dma_release_channel(dma->chan_tx);
 fail_al:
 	devm_kfree(dev, dma);
-	if (ret != -EPROBE_DEFER)
-		dev_info(dev, "can't use DMA\n");
 
 	return ERR_PTR(ret);
 }

drivers/i2c/busses/i2c-stm32f4.c

@@ -797,10 +797,8 @@ static int stm32f4_i2c_probe(struct platform_device *pdev)
 
 	rst = devm_reset_control_get_exclusive(&pdev->dev, NULL);
 	if (IS_ERR(rst)) {
-		ret = PTR_ERR(rst);
-		if (ret != -EPROBE_DEFER)
-			dev_err(&pdev->dev, "Error: Missing reset ctrl\n");
-
+		ret = dev_err_probe(&pdev->dev, PTR_ERR(rst),
+				    "Error: Missing reset ctrl\n");
 		goto clk_free;
 	}
 	reset_control_assert(rst);

drivers/i2c/busses/i2c-stm32f7.c

@@ -18,6 +18,7 @@
 #include <linux/delay.h>
 #include <linux/err.h>
 #include <linux/i2c.h>
+#include <linux/i2c-smbus.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/iopoll.h>
@@ -50,6 +51,7 @@
 
 /* STM32F7 I2C control 1 */
 #define STM32F7_I2C_CR1_PECEN			BIT(23)
+#define STM32F7_I2C_CR1_SMBHEN			BIT(20)
 #define STM32F7_I2C_CR1_WUPEN			BIT(18)
 #define STM32F7_I2C_CR1_SBC			BIT(16)
 #define STM32F7_I2C_CR1_RXDMAEN			BIT(15)
@@ -150,7 +152,12 @@
 
 #define STM32F7_I2C_MAX_LEN			0xff
 #define STM32F7_I2C_DMA_LEN_MIN			0x16
-#define STM32F7_I2C_MAX_SLAVE			0x2
+enum {
+	STM32F7_SLAVE_HOSTNOTIFY,
+	STM32F7_SLAVE_7_10_BITS_ADDR,
+	STM32F7_SLAVE_7_BITS_ADDR,
+	STM32F7_I2C_MAX_SLAVE
+};
 
 #define STM32F7_I2C_DNF_DEFAULT			0
 #define STM32F7_I2C_DNF_MAX			16
@@ -301,6 +308,8 @@ struct stm32f7_i2c_msg {
  * @fmp_creg: register address for clearing Fast Mode Plus bits
  * @fmp_mask: mask for Fast Mode Plus bits in set register
  * @wakeup_src: boolean to know if the device is a wakeup source
+ * @smbus_mode: states that the controller is configured in SMBus mode
+ * @host_notify_client: SMBus host-notify client
  */
 struct stm32f7_i2c_dev {
 	struct i2c_adapter adap;
@@ -327,6 +336,8 @@ struct stm32f7_i2c_dev {
 	u32 fmp_creg;
 	u32 fmp_mask;
 	bool wakeup_src;
+	bool smbus_mode;
+	struct i2c_client *host_notify_client;
 };
 
 /*
@@ -1321,11 +1332,20 @@ static int stm32f7_i2c_get_free_slave_id(struct stm32f7_i2c_dev *i2c_dev,
 	int i;
 
 	/*
-	 * slave[0] supports 7-bit and 10-bit slave address
-	 * slave[1] supports 7-bit slave address only
+	 * slave[STM32F7_SLAVE_HOSTNOTIFY] support only SMBus Host address (0x8)
+	 * slave[STM32F7_SLAVE_7_10_BITS_ADDR] supports 7-bit and 10-bit slave address
+	 * slave[STM32F7_SLAVE_7_BITS_ADDR] supports 7-bit slave address only
 	 */
-	for (i = STM32F7_I2C_MAX_SLAVE - 1; i >= 0; i--) {
-		if (i == 1 && (slave->flags & I2C_CLIENT_TEN))
+	if (i2c_dev->smbus_mode && (slave->addr == 0x08)) {
+		if (i2c_dev->slave[STM32F7_SLAVE_HOSTNOTIFY])
+			goto fail;
+		*id = STM32F7_SLAVE_HOSTNOTIFY;
+		return 0;
+	}
+
+	for (i = STM32F7_I2C_MAX_SLAVE - 1; i > STM32F7_SLAVE_HOSTNOTIFY; i--) {
+		if ((i == STM32F7_SLAVE_7_BITS_ADDR) &&
+		    (slave->flags & I2C_CLIENT_TEN))
 			continue;
 		if (!i2c_dev->slave[i]) {
 			*id = i;
@@ -1333,6 +1353,7 @@ static int stm32f7_i2c_get_free_slave_id(struct stm32f7_i2c_dev *i2c_dev,
 		}
 	}
 
+fail:
 	dev_err(dev, "Slave 0x%x could not be registered\n", slave->addr);
 
 	return -EINVAL;
@@ -1776,7 +1797,13 @@ static int stm32f7_i2c_reg_slave(struct i2c_client *slave)
 	if (!stm32f7_i2c_is_slave_registered(i2c_dev))
 		stm32f7_i2c_enable_wakeup(i2c_dev, true);
 
-	if (id == 0) {
+	switch (id) {
+	case 0:
+		/* Slave SMBus Host */
+		i2c_dev->slave[id] = slave;
+		break;
+
+	case 1:
 		/* Configure Own Address 1 */
 		oar1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR1);
 		oar1 &= ~STM32F7_I2C_OAR1_MASK;
@@ -1789,7 +1816,9 @@ static int stm32f7_i2c_reg_slave(struct i2c_client *slave)
 		oar1 |= STM32F7_I2C_OAR1_OA1EN;
 		i2c_dev->slave[id] = slave;
 		writel_relaxed(oar1, i2c_dev->base + STM32F7_I2C_OAR1);
-	} else if (id == 1) {
+		break;
+
+	case 2:
 		/* Configure Own Address 2 */
 		oar2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR2);
 		oar2 &= ~STM32F7_I2C_OAR2_MASK;
@@ -1802,7 +1831,10 @@ static int stm32f7_i2c_reg_slave(struct i2c_client *slave)
 		oar2 |= STM32F7_I2C_OAR2_OA2EN;
 		i2c_dev->slave[id] = slave;
 		writel_relaxed(oar2, i2c_dev->base + STM32F7_I2C_OAR2);
-	} else {
+		break;
+
+	default:
+		dev_err(dev, "I2C slave id not supported\n");
 		ret = -ENODEV;
 		goto pm_free;
 	}
@@ -1843,10 +1875,10 @@ static int stm32f7_i2c_unreg_slave(struct i2c_client *slave)
 	if (ret < 0)
 		return ret;
 
-	if (id == 0) {
+	if (id == 1) {
 		mask = STM32F7_I2C_OAR1_OA1EN;
 		stm32f7_i2c_clr_bits(base + STM32F7_I2C_OAR1, mask);
-	} else {
+	} else if (id == 2) {
 		mask = STM32F7_I2C_OAR2_OA2EN;
 		stm32f7_i2c_clr_bits(base + STM32F7_I2C_OAR2, mask);
 	}
@@ -1911,14 +1943,51 @@ static int stm32f7_i2c_setup_fm_plus_bits(struct platform_device *pdev,
 					  &i2c_dev->fmp_mask);
 }
 
+static int stm32f7_i2c_enable_smbus_host(struct stm32f7_i2c_dev *i2c_dev)
+{
+	struct i2c_adapter *adap = &i2c_dev->adap;
+	void __iomem *base = i2c_dev->base;
+	struct i2c_client *client;
+
+	client = i2c_new_slave_host_notify_device(adap);
+	if (IS_ERR(client))
+		return PTR_ERR(client);
+
+	i2c_dev->host_notify_client = client;
+
+	/* Enable SMBus Host address */
+	stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, STM32F7_I2C_CR1_SMBHEN);
+
+	return 0;
+}
+
+static void stm32f7_i2c_disable_smbus_host(struct stm32f7_i2c_dev *i2c_dev)
+{
+	void __iomem *base = i2c_dev->base;
+
+	if (i2c_dev->host_notify_client) {
+		/* Disable SMBus Host address */
+		stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR1,
+				     STM32F7_I2C_CR1_SMBHEN);
+		i2c_free_slave_host_notify_device(i2c_dev->host_notify_client);
+	}
+}
+
 static u32 stm32f7_i2c_func(struct i2c_adapter *adap)
 {
-	return I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR | I2C_FUNC_SLAVE |
-		I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
-		I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
-		I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
-		I2C_FUNC_SMBUS_PROC_CALL | I2C_FUNC_SMBUS_PEC |
-		I2C_FUNC_SMBUS_I2C_BLOCK;
+	struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(adap);
+
+	u32 func = I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR | I2C_FUNC_SLAVE |
+		   I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
+		   I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
+		   I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
+		   I2C_FUNC_SMBUS_PROC_CALL | I2C_FUNC_SMBUS_PEC |
+		   I2C_FUNC_SMBUS_I2C_BLOCK;
+
+	if (i2c_dev->smbus_mode)
+		func |= I2C_FUNC_SMBUS_HOST_NOTIFY;
+
+	return func;
 }
 
 static const struct i2c_algorithm stm32f7_i2c_algo = {
@@ -1968,11 +2037,9 @@ static int stm32f7_i2c_probe(struct platform_device *pdev)
 						    "wakeup-source");
 
 	i2c_dev->clk = devm_clk_get(&pdev->dev, NULL);
-	if (IS_ERR(i2c_dev->clk)) {
-		if (PTR_ERR(i2c_dev->clk) != -EPROBE_DEFER)
-			dev_err(&pdev->dev, "Failed to get controller clock\n");
-		return PTR_ERR(i2c_dev->clk);
-	}
+	if (IS_ERR(i2c_dev->clk))
+		return dev_err_probe(&pdev->dev, PTR_ERR(i2c_dev->clk),
+				     "Failed to get controller clock\n");
 
 	ret = clk_prepare_enable(i2c_dev->clk);
 	if (ret) {
@@ -1982,10 +2049,8 @@ static int stm32f7_i2c_probe(struct platform_device *pdev)
 
 	rst = devm_reset_control_get(&pdev->dev, NULL);
 	if (IS_ERR(rst)) {
-		ret = PTR_ERR(rst);
-		if (ret != -EPROBE_DEFER)
-			dev_err(&pdev->dev, "Error: Missing reset ctrl\n");
-
+		ret = dev_err_probe(&pdev->dev, PTR_ERR(rst),
+				    "Error: Missing reset ctrl\n");
 		goto clk_free;
 	}
 	reset_control_assert(rst);
@@ -2052,14 +2117,13 @@ static int stm32f7_i2c_probe(struct platform_device *pdev)
 	i2c_dev->dma = stm32_i2c_dma_request(i2c_dev->dev, phy_addr,
 					     STM32F7_I2C_TXDR,
 					     STM32F7_I2C_RXDR);
-	if (PTR_ERR(i2c_dev->dma) == -ENODEV)
-		i2c_dev->dma = NULL;
-	else if (IS_ERR(i2c_dev->dma)) {
+	if (IS_ERR(i2c_dev->dma)) {
 		ret = PTR_ERR(i2c_dev->dma);
-		if (ret != -EPROBE_DEFER)
-			dev_err(&pdev->dev,
-				"Failed to request dma error %i\n", ret);
-		goto fmp_clear;
+		/* DMA support is optional, only report other errors */
+		if (ret != -ENODEV)
+			goto fmp_clear;
+		dev_dbg(i2c_dev->dev, "No DMA option: fallback using interrupts\n");
+		i2c_dev->dma = NULL;
 	}
 
 	if (i2c_dev->wakeup_src) {
@@ -2084,10 +2148,22 @@ static int stm32f7_i2c_probe(struct platform_device *pdev)
 
 	stm32f7_i2c_hw_config(i2c_dev);
 
+	i2c_dev->smbus_mode = of_property_read_bool(pdev->dev.of_node, "smbus");
+
 	ret = i2c_add_adapter(adap);
 	if (ret)
 		goto pm_disable;
 
+	if (i2c_dev->smbus_mode) {
+		ret = stm32f7_i2c_enable_smbus_host(i2c_dev);
+		if (ret) {
+			dev_err(i2c_dev->dev,
+				"failed to enable SMBus Host-Notify protocol (%d)\n",
+				ret);
+			goto i2c_adapter_remove;
+		}
+	}
+
 	dev_info(i2c_dev->dev, "STM32F7 I2C-%d bus adapter\n", adap->nr);
 
 	pm_runtime_mark_last_busy(i2c_dev->dev);
@@ -2095,6 +2171,9 @@ static int stm32f7_i2c_probe(struct platform_device *pdev)
 
 	return 0;
 
+i2c_adapter_remove:
+	i2c_del_adapter(adap);
+
 pm_disable:
 	pm_runtime_put_noidle(i2c_dev->dev);
 	pm_runtime_disable(i2c_dev->dev);
@@ -2126,6 +2205,8 @@ static int stm32f7_i2c_remove(struct platform_device *pdev)
 {
 	struct stm32f7_i2c_dev *i2c_dev = platform_get_drvdata(pdev);
 
+	stm32f7_i2c_disable_smbus_host(i2c_dev);
+
 	i2c_del_adapter(&i2c_dev->adap);
 	pm_runtime_get_sync(i2c_dev->dev);
 

drivers/i2c/busses/i2c-xiic.c

@@ -46,34 +46,36 @@ enum xiic_endian {
 
 /**
  * struct xiic_i2c - Internal representation of the XIIC I2C bus
- * @dev:	Pointer to device structure
- * @base:	Memory base of the HW registers
- * @wait:	Wait queue for callers
- * @adap:	Kernel adapter representation
- * @tx_msg:	Messages from above to be sent
- * @lock:	Mutual exclusion
- * @tx_pos:	Current pos in TX message
- * @nmsgs:	Number of messages in tx_msg
- * @state:	See STATE_
- * @rx_msg:	Current RX message
- * @rx_pos:	Position within current RX message
+ * @dev: Pointer to device structure
+ * @base: Memory base of the HW registers
+ * @wait: Wait queue for callers
+ * @adap: Kernel adapter representation
+ * @tx_msg: Messages from above to be sent
+ * @lock: Mutual exclusion
+ * @tx_pos: Current pos in TX message
+ * @nmsgs: Number of messages in tx_msg
+ * @rx_msg: Current RX message
+ * @rx_pos: Position within current RX message
  * @endianness: big/little-endian byte order
- * @clk:	Pointer to AXI4-lite input clock
+ * @clk: Pointer to AXI4-lite input clock
+ * @state: See STATE_
+ * @singlemaster: Indicates bus is single master
  */
 struct xiic_i2c {
-	struct device		*dev;
-	void __iomem		*base;
-	wait_queue_head_t	wait;
-	struct i2c_adapter	adap;
-	struct i2c_msg		*tx_msg;
-	struct mutex		lock;
-	unsigned int		tx_pos;
-	unsigned int		nmsgs;
-	enum xilinx_i2c_state	state;
-	struct i2c_msg		*rx_msg;
-	int			rx_pos;
-	enum xiic_endian	endianness;
+	struct device *dev;
+	void __iomem *base;
+	wait_queue_head_t wait;
+	struct i2c_adapter adap;
+	struct i2c_msg *tx_msg;
+	struct mutex lock;
+	unsigned int tx_pos;
+	unsigned int nmsgs;
+	struct i2c_msg *rx_msg;
+	int rx_pos;
+	enum xiic_endian endianness;
 	struct clk *clk;
+	enum xilinx_i2c_state state;
+	bool singlemaster;
 };
 
 
@@ -526,6 +528,15 @@ static int xiic_busy(struct xiic_i2c *i2c)
 	if (i2c->tx_msg)
 		return -EBUSY;
 
+	/* In single master mode bus can only be busy, when in use by this
+	 * driver. If the register indicates bus being busy for some reason we
+	 * should ignore it, since bus will never be released and i2c will be
+	 * stuck forever.
+	 */
+	if (i2c->singlemaster) {
+		return 0;
+	}
+
 	/* for instance if previous transfer was terminated due to TX error
 	 * it might be that the bus is on it's way to become available
 	 * give it at most 3 ms to wake
@@ -811,6 +822,9 @@ static int xiic_i2c_probe(struct platform_device *pdev)
 		goto err_clk_dis;
 	}
 
+	i2c->singlemaster =
+		of_property_read_bool(pdev->dev.of_node, "single-master");
+
 	/*
 	 * Detect endianness
 	 * Try to reset the TX FIFO. Then check the EMPTY flag. If it is not

drivers/i2c/i2c-slave-testunit.c

+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * I2C slave mode testunit
+ *
+ * Copyright (C) 2020 by Wolfram Sang, Sang Engineering <wsa@sang-engineering.com>
+ * Copyright (C) 2020 by Renesas Electronics Corporation
+ */
+
+#include <linux/bitops.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h> /* FIXME: is system_long_wq the best choice? */
+
+#define TU_CUR_VERSION 0x01
+
+enum testunit_cmds {
+	TU_CMD_READ_BYTES = 1,	/* save 0 for ABORT, RESET or similar */
+	TU_CMD_HOST_NOTIFY,
+	TU_NUM_CMDS
+};
+
+enum testunit_regs {
+	TU_REG_CMD,
+	TU_REG_DATAL,
+	TU_REG_DATAH,
+	TU_REG_DELAY,
+	TU_NUM_REGS
+};
+
+enum testunit_flags {
+	TU_FLAG_IN_PROCESS,
+};
+
+struct testunit_data {
+	unsigned long flags;
+	u8 regs[TU_NUM_REGS];
+	u8 reg_idx;
+	struct i2c_client *client;
+	struct delayed_work worker;
+};
+
+static void i2c_slave_testunit_work(struct work_struct *work)
+{
+	struct testunit_data *tu = container_of(work, struct testunit_data, worker.work);
+	struct i2c_msg msg;
+	u8 msgbuf[256];
+	int ret = 0;
+
+	msg.addr = I2C_CLIENT_END;
+	msg.buf = msgbuf;
+
+	switch (tu->regs[TU_REG_CMD]) {
+	case TU_CMD_READ_BYTES:
+		msg.addr = tu->regs[TU_REG_DATAL];
+		msg.flags = I2C_M_RD;
+		msg.len = tu->regs[TU_REG_DATAH];
+		break;
+
+	case TU_CMD_HOST_NOTIFY:
+		msg.addr = 0x08;
+		msg.flags = 0;
+		msg.len = 3;
+		msgbuf[0] = tu->client->addr;
+		msgbuf[1] = tu->regs[TU_REG_DATAL];
+		msgbuf[2] = tu->regs[TU_REG_DATAH];
+		break;
+
+	default:
+		break;
+	}
+
+	if (msg.addr != I2C_CLIENT_END) {
+		ret = i2c_transfer(tu->client->adapter, &msg, 1);
+		/* convert '0 msgs transferred' to errno */
+		ret = (ret == 0) ? -EIO : ret;
+	}
+
+	if (ret < 0)
+		dev_err(&tu->client->dev, "CMD%02X failed (%d)\n", tu->regs[TU_REG_CMD], ret);
+
+	clear_bit(TU_FLAG_IN_PROCESS, &tu->flags);
+}
+
+static int i2c_slave_testunit_slave_cb(struct i2c_client *client,
+				     enum i2c_slave_event event, u8 *val)
+{
+	struct testunit_data *tu = i2c_get_clientdata(client);
+	int ret = 0;
+
+	switch (event) {
+	case I2C_SLAVE_WRITE_RECEIVED:
+		if (test_bit(TU_FLAG_IN_PROCESS, &tu->flags))
+			return -EBUSY;
+
+		if (tu->reg_idx < TU_NUM_REGS)
+			tu->regs[tu->reg_idx] = *val;
+		else
+			ret = -EMSGSIZE;
+
+		if (tu->reg_idx <= TU_NUM_REGS)
+			tu->reg_idx++;
+
+		/* TU_REG_CMD always written at this point */
+		if (tu->regs[TU_REG_CMD] >= TU_NUM_CMDS)
+			ret = -EINVAL;
+
+		break;
+
+	case I2C_SLAVE_STOP:
+		if (tu->reg_idx == TU_NUM_REGS) {
+			set_bit(TU_FLAG_IN_PROCESS, &tu->flags);
+			queue_delayed_work(system_long_wq, &tu->worker,
+					   msecs_to_jiffies(10 * tu->regs[TU_REG_DELAY]));
+		}
+		fallthrough;
+
+	case I2C_SLAVE_WRITE_REQUESTED:
+		tu->reg_idx = 0;
+		break;
+
+	case I2C_SLAVE_READ_REQUESTED:
+	case I2C_SLAVE_READ_PROCESSED:
+		*val = TU_CUR_VERSION;
+		break;
+	}
+
+	return ret;
+}
+
+static int i2c_slave_testunit_probe(struct i2c_client *client)
+{
+	struct testunit_data *tu;
+
+	tu = devm_kzalloc(&client->dev, sizeof(struct testunit_data), GFP_KERNEL);
+	if (!tu)
+		return -ENOMEM;
+
+	tu->client = client;
+	i2c_set_clientdata(client, tu);
+	INIT_DELAYED_WORK(&tu->worker, i2c_slave_testunit_work);
+
+	return i2c_slave_register(client, i2c_slave_testunit_slave_cb);
+};
+
+static int i2c_slave_testunit_remove(struct i2c_client *client)
+{
+	struct testunit_data *tu = i2c_get_clientdata(client);
+
+	cancel_delayed_work_sync(&tu->worker);
+	i2c_slave_unregister(client);
+	return 0;
+}
+
+static const struct i2c_device_id i2c_slave_testunit_id[] = {
+	{ "slave-testunit", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, i2c_slave_testunit_id);
+
+static struct i2c_driver i2c_slave_testunit_driver = {
+	.driver = {
+		.name = "i2c-slave-testunit",
+	},
+	.probe_new = i2c_slave_testunit_probe,
+	.remove = i2c_slave_testunit_remove,
+	.id_table = i2c_slave_testunit_id,
+};
+module_i2c_driver(i2c_slave_testunit_driver);
+
+MODULE_AUTHOR("Wolfram Sang <wsa@sang-engineering.com>");
+MODULE_DESCRIPTION("I2C slave mode test unit");
+MODULE_LICENSE("GPL v2");

drivers/i2c/i2c-smbus.c

@@ -197,6 +197,113 @@ EXPORT_SYMBOL_GPL(i2c_handle_smbus_alert);
 
 module_i2c_driver(smbalert_driver);
 
+#if IS_ENABLED(CONFIG_I2C_SLAVE)
+#define SMBUS_HOST_NOTIFY_LEN	3
+struct i2c_slave_host_notify_status {
+	u8 index;
+	u8 addr;
+};
+
+static int i2c_slave_host_notify_cb(struct i2c_client *client,
+				    enum i2c_slave_event event, u8 *val)
+{
+	struct i2c_slave_host_notify_status *status = client->dev.platform_data;
+
+	switch (event) {
+	case I2C_SLAVE_WRITE_RECEIVED:
+		/* We only retrieve the first byte received (addr)
+		 * since there is currently no support to retrieve the data
+		 * parameter from the client.
+		 */
+		if (status->index == 0)
+			status->addr = *val;
+		if (status->index < U8_MAX)
+			status->index++;
+		break;
+	case I2C_SLAVE_STOP:
+		if (status->index == SMBUS_HOST_NOTIFY_LEN)
+			i2c_handle_smbus_host_notify(client->adapter,
+						     status->addr);
+		fallthrough;
+	case I2C_SLAVE_WRITE_REQUESTED:
+		status->index = 0;
+		break;
+	case I2C_SLAVE_READ_REQUESTED:
+	case I2C_SLAVE_READ_PROCESSED:
+		*val = 0xff;
+		break;
+	}
+
+	return 0;
+}
+
+/**
+ * i2c_new_slave_host_notify_device - get a client for SMBus host-notify support
+ * @adapter: the target adapter
+ * Context: can sleep
+ *
+ * Setup handling of the SMBus host-notify protocol on a given I2C bus segment.
+ *
+ * Handling is done by creating a device and its callback and handling data
+ * received via the SMBus host-notify address (0x8)
+ *
+ * This returns the client, which should be ultimately freed using
+ * i2c_free_slave_host_notify_device(); or an ERRPTR to indicate an error.
+ */
+struct i2c_client *i2c_new_slave_host_notify_device(struct i2c_adapter *adapter)
+{
+	struct i2c_board_info host_notify_board_info = {
+		I2C_BOARD_INFO("smbus_host_notify", 0x08),
+		.flags  = I2C_CLIENT_SLAVE,
+	};
+	struct i2c_slave_host_notify_status *status;
+	struct i2c_client *client;
+	int ret;
+
+	status = kzalloc(sizeof(struct i2c_slave_host_notify_status),
+			 GFP_KERNEL);
+	if (!status)
+		return ERR_PTR(-ENOMEM);
+
+	host_notify_board_info.platform_data = status;
+
+	client = i2c_new_client_device(adapter, &host_notify_board_info);
+	if (IS_ERR(client)) {
+		kfree(status);
+		return client;
+	}
+
+	ret = i2c_slave_register(client, i2c_slave_host_notify_cb);
+	if (ret) {
+		i2c_unregister_device(client);
+		kfree(status);
+		return ERR_PTR(ret);
+	}
+
+	return client;
+}
+EXPORT_SYMBOL_GPL(i2c_new_slave_host_notify_device);
+
+/**
+ * i2c_free_slave_host_notify_device - free the client for SMBus host-notify
+ * support
+ * @client: the client to free
+ * Context: can sleep
+ *
+ * Free the i2c_client allocated via i2c_new_slave_host_notify_device
+ */
+void i2c_free_slave_host_notify_device(struct i2c_client *client)
+{
+	if (IS_ERR_OR_NULL(client))
+		return;
+
+	i2c_slave_unregister(client);
+	kfree(client->dev.platform_data);
+	i2c_unregister_device(client);
+}
+EXPORT_SYMBOL_GPL(i2c_free_slave_host_notify_device);
+#endif
+
 /*
  * SPD is not part of SMBus but we include it here for convenience as the
  * target systems are the same.

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

@@ -85,18 +85,14 @@ static int i2c_mux_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	mux->control = devm_mux_control_get(dev, NULL);
-	if (IS_ERR(mux->control)) {
-		if (PTR_ERR(mux->control) != -EPROBE_DEFER)
-			dev_err(dev, "failed to get control-mux\n");
-		return PTR_ERR(mux->control);
-	}
+	if (IS_ERR(mux->control))
+		return dev_err_probe(dev, PTR_ERR(mux->control),
+				     "failed to get control-mux\n");
 
 	parent = mux_parent_adapter(dev);
-	if (IS_ERR(parent)) {
-		if (PTR_ERR(parent) != -EPROBE_DEFER)
-			dev_err(dev, "failed to get i2c-parent adapter\n");
-		return PTR_ERR(parent);
-	}
+	if (IS_ERR(parent))
+		return dev_err_probe(dev, PTR_ERR(parent),
+				     "failed to get i2c-parent adapter\n");
 
 	children = of_get_child_count(np);
 

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

@@ -171,13 +171,9 @@ static int i2c_mux_reg_probe(struct platform_device *pdev)
 			sizeof(mux->data));
 	} else {
 		ret = i2c_mux_reg_probe_dt(mux, pdev);
-		if (ret == -EPROBE_DEFER)
-			return ret;
-
-		if (ret < 0) {
-			dev_err(&pdev->dev, "Error parsing device tree");
-			return ret;
-		}
+		if (ret < 0)
+			return dev_err_probe(&pdev->dev, ret,
+					     "Error parsing device tree");
 	}
 
 	parent = i2c_get_adapter(mux->data.parent);

drivers/misc/eeprom/at24.c

@@ -8,6 +8,7 @@
 
 #include <linux/acpi.h>
 #include <linux/bitops.h>
+#include <linux/capability.h>
 #include <linux/delay.h>
 #include <linux/i2c.h>
 #include <linux/init.h>
@@ -89,6 +90,7 @@ struct at24_data {
 
 	struct nvmem_device *nvmem;
 	struct regulator *vcc_reg;
+	void (*read_post)(unsigned int off, char *buf, size_t count);
 
 	/*
 	 * Some chips tie up multiple I2C addresses; dummy devices reserve
@@ -121,6 +123,7 @@ MODULE_PARM_DESC(at24_write_timeout, "Time (in ms) to try writes (default 25)");
 struct at24_chip_data {
 	u32 byte_len;
 	u8 flags;
+	void (*read_post)(unsigned int off, char *buf, size_t count);
 };
 
 #define AT24_CHIP_DATA(_name, _len, _flags)				\
@@ -128,6 +131,32 @@ struct at24_chip_data {
 		.byte_len = _len, .flags = _flags,			\
 	}
 
+#define AT24_CHIP_DATA_CB(_name, _len, _flags, _read_post)		\
+	static const struct at24_chip_data _name = {			\
+		.byte_len = _len, .flags = _flags,			\
+		.read_post = _read_post,				\
+	}
+
+static void at24_read_post_vaio(unsigned int off, char *buf, size_t count)
+{
+	int i;
+
+	if (capable(CAP_SYS_ADMIN))
+		return;
+
+	/*
+	 * Hide VAIO private settings to regular users:
+	 * - BIOS passwords: bytes 0x00 to 0x0f
+	 * - UUID: bytes 0x10 to 0x1f
+	 * - Serial number: 0xc0 to 0xdf
+	 */
+	for (i = 0; i < count; i++) {
+		if ((off + i <= 0x1f) ||
+		    (off + i >= 0xc0 && off + i <= 0xdf))
+			buf[i] = 0;
+	}
+}
+
 /* needs 8 addresses as A0-A2 are ignored */
 AT24_CHIP_DATA(at24_data_24c00, 128 / 8, AT24_FLAG_TAKE8ADDR);
 /* old variants can't be handled with this generic entry! */
@@ -144,6 +173,10 @@ AT24_CHIP_DATA(at24_data_24mac602, 64 / 8,
 /* spd is a 24c02 in memory DIMMs */
 AT24_CHIP_DATA(at24_data_spd, 2048 / 8,
 	AT24_FLAG_READONLY | AT24_FLAG_IRUGO);
+/* 24c02_vaio is a 24c02 on some Sony laptops */
+AT24_CHIP_DATA_CB(at24_data_24c02_vaio, 2048 / 8,
+	AT24_FLAG_READONLY | AT24_FLAG_IRUGO,
+	at24_read_post_vaio);
 AT24_CHIP_DATA(at24_data_24c04, 4096 / 8, 0);
 AT24_CHIP_DATA(at24_data_24cs04, 16,
 	AT24_FLAG_SERIAL | AT24_FLAG_READONLY);
@@ -177,6 +210,7 @@ static const struct i2c_device_id at24_ids[] = {
 	{ "24mac402",	(kernel_ulong_t)&at24_data_24mac402 },
 	{ "24mac602",	(kernel_ulong_t)&at24_data_24mac602 },
 	{ "spd",	(kernel_ulong_t)&at24_data_spd },
+	{ "24c02-vaio",	(kernel_ulong_t)&at24_data_24c02_vaio },
 	{ "24c04",	(kernel_ulong_t)&at24_data_24c04 },
 	{ "24cs04",	(kernel_ulong_t)&at24_data_24cs04 },
 	{ "24c08",	(kernel_ulong_t)&at24_data_24c08 },
@@ -388,7 +422,7 @@ static int at24_read(void *priv, unsigned int off, void *val, size_t count)
 	struct at24_data *at24;
 	struct device *dev;
 	char *buf = val;
-	int ret;
+	int i, ret;
 
 	at24 = priv;
 	dev = at24_base_client_dev(at24);
@@ -411,22 +445,22 @@ static int at24_read(void *priv, unsigned int off, void *val, size_t count)
 	 */
 	mutex_lock(&at24->lock);
 
-	while (count) {
-		ret = at24_regmap_read(at24, buf, off, count);
+	for (i = 0; count; i += ret, count -= ret) {
+		ret = at24_regmap_read(at24, buf + i, off + i, count);
 		if (ret < 0) {
 			mutex_unlock(&at24->lock);
 			pm_runtime_put(dev);
 			return ret;
 		}
-		buf += ret;
-		off += ret;
-		count -= ret;
 	}
 
 	mutex_unlock(&at24->lock);
 
 	pm_runtime_put(dev);
 
+	if (unlikely(at24->read_post))
+		at24->read_post(off, buf, i);
+
 	return 0;
 }
 
@@ -654,6 +688,7 @@ static int at24_probe(struct i2c_client *client)
 	at24->byte_len = byte_len;
 	at24->page_size = page_size;
 	at24->flags = flags;
+	at24->read_post = cdata->read_post;
 	at24->num_addresses = num_addresses;
 	at24->offset_adj = at24_get_offset_adj(flags, byte_len);
 	at24->client[0].client = client;
@@ -678,8 +713,30 @@ static int at24_probe(struct i2c_client *client)
 			return err;
 	}
 
-	nvmem_config.name = dev_name(dev);
+	/*
+	 * If the 'label' property is not present for the AT24 EEPROM,
+	 * then nvmem_config.id is initialised to NVMEM_DEVID_AUTO,
+	 * and this will append the 'devid' to the name of the NVMEM
+	 * device. This is purely legacy and the AT24 driver has always
+	 * defaulted to this. However, if the 'label' property is
+	 * present then this means that the name is specified by the
+	 * firmware and this name should be used verbatim and so it is
+	 * not necessary to append the 'devid'.
+	 */
+	if (device_property_present(dev, "label")) {
+		nvmem_config.id = NVMEM_DEVID_NONE;
+		err = device_property_read_string(dev, "label",
+						  &nvmem_config.name);
+		if (err)
+			return err;
+	} else {
+		nvmem_config.id = NVMEM_DEVID_AUTO;
+		nvmem_config.name = dev_name(dev);
+	}
+
+	nvmem_config.type = NVMEM_TYPE_EEPROM;
 	nvmem_config.dev = dev;
+	nvmem_config.id = NVMEM_DEVID_AUTO;
 	nvmem_config.read_only = !writable;
 	nvmem_config.root_only = !(flags & AT24_FLAG_IRUGO);
 	nvmem_config.owner = THIS_MODULE;

drivers/misc/eeprom/eeprom.c

@@ -76,7 +76,7 @@ static ssize_t eeprom_read(struct file *filp, struct kobject *kobj,
 			   struct bin_attribute *bin_attr,
 			   char *buf, loff_t off, size_t count)
 {
-	struct i2c_client *client = to_i2c_client(kobj_to_dev(kobj));
+	struct i2c_client *client = kobj_to_i2c_client(kobj);
 	struct eeprom_data *data = i2c_get_clientdata(client);
 	u8 slice;
 

include/linux/i2c-smbus.h

@@ -38,6 +38,18 @@ static inline int of_i2c_setup_smbus_alert(struct i2c_adapter *adap)
 	return 0;
 }
 #endif
+#if IS_ENABLED(CONFIG_I2C_SMBUS) && IS_ENABLED(CONFIG_I2C_SLAVE)
+struct i2c_client *i2c_new_slave_host_notify_device(struct i2c_adapter *adapter);
+void i2c_free_slave_host_notify_device(struct i2c_client *client);
+#else
+static inline struct i2c_client *i2c_new_slave_host_notify_device(struct i2c_adapter *adapter)
+{
+	return ERR_PTR(-ENOSYS);
+}
+static inline void i2c_free_slave_host_notify_device(struct i2c_client *client)
+{
+}
+#endif
 
 #if IS_ENABLED(CONFIG_I2C_SMBUS) && IS_ENABLED(CONFIG_DMI)
 void i2c_register_spd(struct i2c_adapter *adap);

include/linux/i2c.h

@@ -344,7 +344,7 @@ const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id,
 
 static inline struct i2c_client *kobj_to_i2c_client(struct kobject *kobj)
 {
-	struct device * const dev = container_of(kobj, struct device, kobj);
+	struct device * const dev = kobj_to_dev(kobj);
 	return to_i2c_client(dev);
 }