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authorLinus Torvalds <torvalds@linux-foundation.org>2020-10-21 19:54:05 +0200
committerLinus Torvalds <torvalds@linux-foundation.org>2020-10-21 19:54:05 +0200
commitb5df4b5c28b232d1fc0b48660f44668faebb0bcb (patch)
tree52cdd0fd3b4aa6e366384ada29524ac642e573d1 /Documentation
parentMerge tag 'ceph-for-5.10-rc1' of git://github.com/ceph/ceph-client (diff)
parentDocumentation: i2c: add testunit docs to index (diff)
downloadlinux-b5df4b5c28b232d1fc0b48660f44668faebb0bcb.tar.xz
linux-b5df4b5c28b232d1fc0b48660f44668faebb0bcb.zip
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redundant check in tegra_i2c_issue_bus_clear() i2c: tegra: Remove likely/unlikely from the code i2c: tegra: Remove outdated barrier() i2c: tegra: Clean up variable types i2c: tegra: Reorder location of functions in the code i2c: tegra: Clean up probe function ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/devicetree/bindings/eeprom/at24.yaml3
-rw-r--r--Documentation/devicetree/bindings/i2c/i2c-imx-lpi2c.yaml29
-rw-r--r--Documentation/devicetree/bindings/i2c/i2c-imx.yaml8
-rw-r--r--Documentation/devicetree/bindings/i2c/i2c.txt5
-rw-r--r--Documentation/devicetree/bindings/i2c/ingenic,i2c.yaml12
-rw-r--r--Documentation/devicetree/bindings/i2c/mellanox,i2c-mlxbf.txt42
-rw-r--r--Documentation/i2c/busses/i2c-i801.rst1
-rw-r--r--Documentation/i2c/index.rst1
-rw-r--r--Documentation/i2c/slave-testunit-backend.rst69
9 files changed, 159 insertions, 11 deletions
diff --git a/Documentation/devicetree/bindings/eeprom/at24.yaml b/Documentation/devicetree/bindings/eeprom/at24.yaml
index 4cee72d53318..6edfa705b486 100644
--- a/Documentation/devicetree/bindings/eeprom/at24.yaml
+++ b/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
diff --git a/Documentation/devicetree/bindings/i2c/i2c-imx-lpi2c.yaml b/Documentation/devicetree/bindings/i2c/i2c-imx-lpi2c.yaml
index ac0bc5dd64d6..29b9447f3b84 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-imx-lpi2c.yaml
+++ b/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>;
diff --git a/Documentation/devicetree/bindings/i2c/i2c-imx.yaml b/Documentation/devicetree/bindings/i2c/i2c-imx.yaml
index 810536953177..f23966b0d6c6 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-imx.yaml
+++ b/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:
+ - $ref: /schemas/i2c/i2c-controller.yaml#
+
properties:
compatible:
oneOf:
@@ -19,6 +22,9 @@ properties:
- const: fsl,imx35-i2c
- const: fsl,imx1-i2c
- items:
+ - const: fsl,imx7d-i2c
+ - const: fsl,imx21-i2c
+ - items:
- enum:
- fsl,imx25-i2c
- fsl,imx27-i2c
@@ -75,7 +81,7 @@ required:
- interrupts
- clocks
-additionalProperties: false
+unevaluatedProperties: false
examples:
- |
diff --git a/Documentation/devicetree/bindings/i2c/i2c.txt b/Documentation/devicetree/bindings/i2c/i2c.txt
index a21c359b9f02..df41f72afc87 100644
--- a/Documentation/devicetree/bindings/i2c/i2c.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c.txt
@@ -87,6 +87,11 @@ wants to support one of the below features, it should adapt these bindings.
this information to detect a stalled bus more reliably, for example.
Can not be combined with 'multi-master'.
+- smbus
+ states that additional SMBus restrictions and features apply to this bus.
+ Examples of features are SMBusHostNotify and SMBusAlert. Examples of
+ restrictions are more reserved addresses and timeout definitions.
+
Required properties (per child device)
--------------------------------------
diff --git a/Documentation/devicetree/bindings/i2c/ingenic,i2c.yaml b/Documentation/devicetree/bindings/i2c/ingenic,i2c.yaml
index 682ed1bbf5c6..0e7b4b8a7e48 100644
--- a/Documentation/devicetree/bindings/i2c/ingenic,i2c.yaml
+++ b/Documentation/devicetree/bindings/i2c/ingenic,i2c.yaml
@@ -17,9 +17,13 @@ properties:
pattern: "^i2c@[0-9a-f]+$"
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>;
diff --git a/Documentation/devicetree/bindings/i2c/mellanox,i2c-mlxbf.txt b/Documentation/devicetree/bindings/i2c/mellanox,i2c-mlxbf.txt
new file mode 100644
index 000000000000..566ea861aa00
--- /dev/null
+++ b/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>;
+};
diff --git a/Documentation/i2c/busses/i2c-i801.rst b/Documentation/i2c/busses/i2c-i801.rst
index faf32330c335..42bbdd6e7fd8 100644
--- a/Documentation/i2c/busses/i2c-i801.rst
+++ b/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
diff --git a/Documentation/i2c/index.rst b/Documentation/i2c/index.rst
index 8a2ad3845191..8b76217e370a 100644
--- a/Documentation/i2c/index.rst
+++ b/Documentation/i2c/index.rst
@@ -47,6 +47,7 @@ Slave I2C
slave-interface
slave-eeprom-backend
+ slave-testunit-backend
Advanced topics
===============
diff --git a/Documentation/i2c/slave-testunit-backend.rst b/Documentation/i2c/slave-testunit-backend.rst
new file mode 100644
index 000000000000..2c38e64f0bac
--- /dev/null
+++ b/Documentation/i2c/slave-testunit-backend.rst
@@ -0,0 +1,69 @@
+.. 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