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

…nel/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  i2c: tegra: Remove outdated barrier()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

@@ -9,36 +9,53 @@ title: Freescale Low Power Inter IC (LPI2C) for i.MX
 maintainers:
   - Anson Huang <[email protected]>
 
+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
 
   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 <[email protected]>
 
+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

@@ -0,0 +1,42 @@
+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

@@ -0,0 +1,69 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+================================
+Linux I2C slave testunit backend
+================================
+
+by Wolfram Sang <[email protected]> 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 <[email protected]>
+L:	[email protected]
+S:	Supported
+F:	drivers/i2c/busses/i2c-mlxbf.c
+
 MELLANOX ETHERNET DRIVER (mlx4_en)
 M:	Tariq Toukan <[email protected]>
 L:	[email protected]

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))