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authorLinus Torvalds <torvalds@linux-foundation.org>2018-08-21 17:40:46 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2018-08-21 17:40:46 -0700
commit99cc7ad46b62ef20b0478147677bebd1157bd9cf (patch)
treef07f33826e6947108234707030867d969230611d /Documentation
parent0214f46b3a0383d6e33c297e7706216b6a550e4b (diff)
parent19358d4488db7e6a04e940730cc75909d7d1e0d8 (diff)
Merge branch 'i2c/for-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang: - the core has now a lockless variant of i2c_smbus_xfer. Some open coded versions of this got removed in drivers. This also enables proper SCCB support in regmap. - locking got a more precise naming. i2c_{un}lock_adapter() had to go, and we know use i2c_lock_bus() consistently with flags like I2C_LOCK_ROOT_ADAPTER and I2C_LOCK_SEGMENT to avoid ambiguity. - the gpio fault injector got a new delicate testcase - the bus recovery procedure got fixed to handle the new testcase correctly - a new quirk flag for controllers not able to handle zero length messages together with driver updates to use it - new drivers: FSI bus attached I2C masters, GENI I2C controller, Owl family S900 - and a good set of driver improvements and bugfixes * 'i2c/for-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (77 commits) i2c: rcar: implement STOP and REP_START according to docs i2c: rcar: refactor private flags i2c: core: ACPI: Make acpi_gsb_i2c_read_bytes() check i2c_transfer return value i2c: core: ACPI: Properly set status byte to 0 for multi-byte writes dt-bindings: i2c: rcar: Add r8a774a1 support dt-bindings: i2c: sh_mobile: Add r8a774a1 support i2c: imx: Simplify stopped state tracking i2c: imx: Fix race condition in dma read i2c: pasemi: remove hardcoded bus numbers on smbus i2c: designware: Add SPDX license tag i2c: designware: Convert to use struct i2c_timings i2c: core: Parse SDA hold time from firmware i2c: designware-pcidrv: Mark expected switch fall-through i2c: amd8111: Mark expected switch fall-through i2c: sh_mobile: use core to detect 'no zero length read' quirk i2c: xlr: use core to detect 'no zero length' quirk i2c: rcar: use core to detect 'no zero length' quirk i2c: stu300: use core to detect 'no zero length' quirk i2c: pmcmsp: use core to detect 'no zero length' quirk i2c: mxs: use core to detect 'no zero length' quirk ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/devicetree/bindings/eeprom/at24.txt2
-rw-r--r--Documentation/devicetree/bindings/i2c/i2c-fsi.txt40
-rw-r--r--Documentation/devicetree/bindings/i2c/i2c-owl.txt27
-rw-r--r--Documentation/devicetree/bindings/i2c/i2c-rcar.txt5
-rw-r--r--Documentation/devicetree/bindings/i2c/i2c-sh_mobile.txt4
-rw-r--r--Documentation/i2c/busses/i2c-i80111
-rw-r--r--Documentation/i2c/gpio-fault-injection49
7 files changed, 118 insertions, 20 deletions
diff --git a/Documentation/devicetree/bindings/eeprom/at24.txt b/Documentation/devicetree/bindings/eeprom/at24.txt
index 61d833abafbf..aededdbc262b 100644
--- a/Documentation/devicetree/bindings/eeprom/at24.txt
+++ b/Documentation/devicetree/bindings/eeprom/at24.txt
@@ -72,6 +72,8 @@ Optional properties:
- wp-gpios: GPIO to which the write-protect pin of the chip is connected.
+ - address-width: number of address bits (one of 8, 16).
+
Example:
eeprom@52 {
diff --git a/Documentation/devicetree/bindings/i2c/i2c-fsi.txt b/Documentation/devicetree/bindings/i2c/i2c-fsi.txt
new file mode 100644
index 000000000000..b1be2ceb7e69
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/i2c-fsi.txt
@@ -0,0 +1,40 @@
+Device-tree bindings for FSI-attached I2C master and busses
+-----------------------------------------------------------
+
+Required properties:
+ - compatible = "ibm,i2c-fsi";
+ - reg = < address size >; : The FSI CFAM address and address
+ space size.
+ - #address-cells = <1>; : Number of address cells in child
+ nodes.
+ - #size-cells = <0>; : Number of size cells in child nodes.
+ - child nodes : Nodes to describe busses off the I2C
+ master.
+
+Child node required properties:
+ - reg = < port number > : The port number on the I2C master.
+
+Child node optional properties:
+ - child nodes : Nodes to describe devices on the I2C
+ bus.
+
+Examples:
+
+ i2c@1800 {
+ compatible = "ibm,i2c-fsi";
+ reg = < 0x1800 0x400 >;
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ i2c-bus@0 {
+ reg = <0>;
+ };
+
+ i2c-bus@1 {
+ reg = <1>;
+
+ eeprom@50 {
+ compatible = "vendor,dev-name";
+ };
+ };
+ };
diff --git a/Documentation/devicetree/bindings/i2c/i2c-owl.txt b/Documentation/devicetree/bindings/i2c/i2c-owl.txt
new file mode 100644
index 000000000000..b743fe444e9f
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/i2c-owl.txt
@@ -0,0 +1,27 @@
+Actions Semiconductor Owl I2C controller
+
+Required properties:
+
+- compatible : Should be "actions,s900-i2c".
+- reg : Offset and length of the register set for the device.
+- #address-cells : Should be 1.
+- #size-cells : Should be 0.
+- interrupts : A single interrupt specifier.
+- clocks : Phandle of the clock feeding the I2C controller.
+
+Optional properties:
+
+- clock-frequency : Desired I2C bus clock frequency in Hz. As only Normal and
+ Fast modes are supported, possible values are 100000 and
+ 400000.
+Examples:
+
+ i2c0: i2c@e0170000 {
+ compatible = "actions,s900-i2c";
+ reg = <0 0xe0170000 0 0x1000>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ interrupts = <GIC_SPI 25 IRQ_TYPE_LEVEL_HIGH>;
+ clocks = <&clock CLK_I2C0>;
+ clock-frequency = <100000>;
+ };
diff --git a/Documentation/devicetree/bindings/i2c/i2c-rcar.txt b/Documentation/devicetree/bindings/i2c/i2c-rcar.txt
index 7ce8fae55537..39cd21d95810 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-rcar.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-rcar.txt
@@ -4,6 +4,7 @@ Required properties:
- compatible:
"renesas,i2c-r8a7743" if the device is a part of a R8A7743 SoC.
"renesas,i2c-r8a7745" if the device is a part of a R8A7745 SoC.
+ "renesas,i2c-r8a774a1" if the device is a part of a R8A774A1 SoC.
"renesas,i2c-r8a7778" if the device is a part of a R8A7778 SoC.
"renesas,i2c-r8a7779" if the device is a part of a R8A7779 SoC.
"renesas,i2c-r8a7790" if the device is a part of a R8A7790 SoC.
@@ -16,11 +17,13 @@ Required properties:
"renesas,i2c-r8a77965" if the device is a part of a R8A77965 SoC.
"renesas,i2c-r8a77970" if the device is a part of a R8A77970 SoC.
"renesas,i2c-r8a77980" if the device is a part of a R8A77980 SoC.
+ "renesas,i2c-r8a77990" if the device is a part of a R8A77990 SoC.
"renesas,i2c-r8a77995" if the device is a part of a R8A77995 SoC.
"renesas,rcar-gen1-i2c" for a generic R-Car Gen1 compatible device.
"renesas,rcar-gen2-i2c" for a generic R-Car Gen2 or RZ/G1 compatible
device.
- "renesas,rcar-gen3-i2c" for a generic R-Car Gen3 compatible device.
+ "renesas,rcar-gen3-i2c" for a generic R-Car Gen3 or RZ/G2 compatible
+ device.
"renesas,i2c-rcar" (deprecated)
When compatible with the generic version, nodes must list the
diff --git a/Documentation/devicetree/bindings/i2c/i2c-sh_mobile.txt b/Documentation/devicetree/bindings/i2c/i2c-sh_mobile.txt
index fc7e17802746..872673adff5a 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-sh_mobile.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-sh_mobile.txt
@@ -6,6 +6,7 @@ Required properties:
- "renesas,iic-r8a7740" (R-Mobile A1)
- "renesas,iic-r8a7743" (RZ/G1M)
- "renesas,iic-r8a7745" (RZ/G1E)
+ - "renesas,iic-r8a774a1" (RZ/G2M)
- "renesas,iic-r8a7790" (R-Car H2)
- "renesas,iic-r8a7791" (R-Car M2-W)
- "renesas,iic-r8a7792" (R-Car V2H)
@@ -17,7 +18,8 @@ Required properties:
- "renesas,iic-sh73a0" (SH-Mobile AG5)
- "renesas,rcar-gen2-iic" (generic R-Car Gen2 or RZ/G1
compatible device)
- - "renesas,rcar-gen3-iic" (generic R-Car Gen3 compatible device)
+ - "renesas,rcar-gen3-iic" (generic R-Car Gen3 or RZ/G2
+ compatible device)
- "renesas,rmobile-iic" (generic device)
When compatible with a generic R-Car version, nodes
diff --git a/Documentation/i2c/busses/i2c-i801 b/Documentation/i2c/busses/i2c-i801
index 65514c251318..d1ee484a787d 100644
--- a/Documentation/i2c/busses/i2c-i801
+++ b/Documentation/i2c/busses/i2c-i801
@@ -21,24 +21,21 @@ Supported adapters:
* Intel DH89xxCC (PCH)
* Intel Panther Point (PCH)
* Intel Lynx Point (PCH)
- * Intel Lynx Point-LP (PCH)
* Intel Avoton (SOC)
* Intel Wellsburg (PCH)
* Intel Coleto Creek (PCH)
* Intel Wildcat Point (PCH)
- * Intel Wildcat Point-LP (PCH)
* Intel BayTrail (SOC)
* Intel Braswell (SOC)
- * Intel Sunrise Point-H (PCH)
- * Intel Sunrise Point-LP (PCH)
- * Intel Kaby Lake-H (PCH)
+ * Intel Sunrise Point (PCH)
+ * Intel Kaby Lake (PCH)
* Intel DNV (SOC)
* Intel Broxton (SOC)
* Intel Lewisburg (PCH)
* Intel Gemini Lake (SOC)
- * Intel Cannon Lake-H (PCH)
- * Intel Cannon Lake-LP (PCH)
+ * Intel Cannon Lake (PCH)
* Intel Cedar Fork (PCH)
+ * Intel Ice Lake (PCH)
Datasheets: Publicly available at the Intel website
On Intel Patsburg and later chipsets, both the normal host SMBus controller
diff --git a/Documentation/i2c/gpio-fault-injection b/Documentation/i2c/gpio-fault-injection
index e0c4f775e239..a4ce62090fd5 100644
--- a/Documentation/i2c/gpio-fault-injection
+++ b/Documentation/i2c/gpio-fault-injection
@@ -34,21 +34,48 @@ I2C specification version 4, section 3.1.16) using the helpers of the Linux I2C
core (see 'struct bus_recovery_info'). However, the bus recovery will not
succeed because SDA is still pinned low until you manually release it again
with "echo 1 > sda". A test with an automatic release can be done with the
-'incomplete_transfer' file.
+following class of fault injectors.
-"incomplete_transfer"
----------------------
+Introduction to incomplete transfers
+------------------------------------
+
+The following fault injectors create situations where SDA will be held low by a
+device. Bus recovery should be able to fix these situations. But please note:
+there are I2C client devices which detect a stuck SDA on their side and release
+it on their own after a few milliseconds. Also, there might be an external
+device deglitching and monitoring the I2C bus. It could also detect a stuck SDA
+and will init a bus recovery on its own. If you want to implement bus recovery
+in a bus master driver, make sure you checked your hardware setup for such
+devices before. And always verify with a scope or logic analyzer!
+
+"incomplete_address_phase"
+--------------------------
This file is write only and you need to write the address of an existing I2C
-client device to it. Then, a transfer to this device will be started, but it
-will stop at the ACK phase after the address of the client has been
+client device to it. Then, a read transfer to this device will be started, but
+it will stop at the ACK phase after the address of the client has been
transmitted. Because the device will ACK its presence, this results in SDA
being pulled low by the device while SCL is high. So, similar to the "sda" file
above, the bus master under test should detect this condition and try a bus
recovery. This time, however, it should succeed and the device should release
-SDA after toggling SCL. Please note: there are I2C client devices which detect
-a stuck SDA on their side and release it on their own after a few milliseconds.
-Also, there are external devices deglitching and monitoring the I2C bus. They
-can also detect a stuck SDA and will init a bus recovery on their own. If you
-want to implement bus recovery in a bus master driver, make sure you checked
-your hardware setup carefully before.
+SDA after toggling SCL.
+
+"incomplete_write_byte"
+-----------------------
+
+Similar to above, this file is write only and you need to write the address of
+an existing I2C client device to it.
+
+The injector will again stop at one ACK phase, so the device will keep SDA low
+because it acknowledges data. However, there are two differences compared to
+'incomplete_address_phase':
+
+a) the message sent out will be a write message
+b) after the address byte, a 0x00 byte will be transferred. Then, stop at ACK.
+
+This is a highly delicate state, the device is set up to write any data to
+register 0x00 (if it has registers) when further clock pulses happen on SCL.
+This is why bus recovery (up to 9 clock pulses) must either check SDA or send
+additional STOP conditions to ensure the bus has been released. Otherwise
+random data will be written to a device!
+