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author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-04-09 19:45:40 +0400 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-04-09 19:45:40 +0400 |
commit | 39de65aa2c3eee901db020a4f1396998e09602a3 (patch) | |
tree | 0582450ec0b5b6b9778275b431207145d5fedfc8 /Documentation | |
parent | 97e18dc007546fce8e99098480b921a02ebb3037 (diff) | |
parent | 1fbeab0b8fd5e655ffef8a793b869eb7dffe0337 (diff) | |
download | linux-39de65aa2c3eee901db020a4f1396998e09602a3.tar.xz |
Merge branch 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:
"Here is the pull request from the i2c subsystem. It got a little
delayed because I needed to wait for a dependency to be included
(commit b424080a9e08: "reset: Add optional resets and stubs"). Plus,
I had some email problems. All done now, the highlights are:
- drivers can now deprecate their use of i2c classes. That shouldn't
be used on embedded platforms anyhow and was often blindly
copy&pasted. This mechanism gives users time to switch away and
ultimately boot faster once the use of classes for those drivers is
gone for good.
- new drivers for QUP, Cadence, efm32
- tracepoint support for I2C and SMBus
- bigger cleanups for the mv64xxx, nomadik, and designware drivers
And the usual bugfixes, cleanups, feature additions. Most stuff has
been in linux-next for a while. Just some hot fixes and new drivers
were added a bit more recently."
* 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (63 commits)
i2c: cadence: fix Kconfig dependency
i2c: Add driver for Cadence I2C controller
i2c: cadence: Document device tree bindings
Documentation: i2c: improve section about flags mangling the protocol
i2c: qup: use proper type fro clk_freq
i2c: qup: off by ones in qup_i2c_probe()
i2c: efm32: fix binding doc
MAINTAINERS: update I2C web resources
i2c: qup: New bus driver for the Qualcomm QUP I2C controller
i2c: qup: Add device tree bindings information
i2c: i2c-xiic: deprecate class based instantiation
i2c: i2c-sirf: deprecate class based instantiation
i2c: i2c-mv64xxx: deprecate class based instantiation
i2c: i2c-designware-platdrv: deprecate class based instantiation
i2c: i2c-davinci: deprecate class based instantiation
i2c: i2c-bcm2835: deprecate class based instantiation
i2c: mv64xxx: Fix reset controller handling
i2c: omap: fix usage of IS_ERR_VALUE with pm_runtime_get_sync
i2c: efm32: new bus driver
i2c: exynos5: remove unnecessary cast of void pointer
...
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/devicetree/bindings/i2c/i2c-at91.txt | 2 | ||||
-rw-r--r-- | Documentation/devicetree/bindings/i2c/i2c-cadence.txt | 24 | ||||
-rw-r--r-- | Documentation/devicetree/bindings/i2c/i2c-designware.txt | 8 | ||||
-rw-r--r-- | Documentation/devicetree/bindings/i2c/i2c-efm32.txt | 34 | ||||
-rw-r--r-- | Documentation/devicetree/bindings/i2c/i2c-mv64xxx.txt | 20 | ||||
-rw-r--r-- | Documentation/devicetree/bindings/i2c/i2c-rcar.txt | 14 | ||||
-rw-r--r-- | Documentation/devicetree/bindings/i2c/qcom,i2c-qup.txt | 40 | ||||
-rw-r--r-- | Documentation/i2c/busses/i2c-i801 | 1 | ||||
-rw-r--r-- | Documentation/i2c/functionality | 2 | ||||
-rw-r--r-- | Documentation/i2c/i2c-protocol | 35 |
10 files changed, 154 insertions, 26 deletions
diff --git a/Documentation/devicetree/bindings/i2c/i2c-at91.txt b/Documentation/devicetree/bindings/i2c/i2c-at91.txt index 4fade84bea16..388f0a275fba 100644 --- a/Documentation/devicetree/bindings/i2c/i2c-at91.txt +++ b/Documentation/devicetree/bindings/i2c/i2c-at91.txt @@ -12,6 +12,7 @@ Required properties : - clocks: phandles to input clocks. Optional properties: +- clock-frequency: Desired I2C bus frequency in Hz, otherwise defaults to 100000 - Child nodes conforming to i2c bus binding Examples : @@ -23,6 +24,7 @@ i2c0: i2c@fff84000 { #address-cells = <1>; #size-cells = <0>; clocks = <&twi0_clk>; + clock-frequency = <400000>; 24c512@50 { compatible = "24c512"; diff --git a/Documentation/devicetree/bindings/i2c/i2c-cadence.txt b/Documentation/devicetree/bindings/i2c/i2c-cadence.txt new file mode 100644 index 000000000000..7cb0b5608f49 --- /dev/null +++ b/Documentation/devicetree/bindings/i2c/i2c-cadence.txt @@ -0,0 +1,24 @@ +Binding for the Cadence I2C controller + +Required properties: + - reg: Physical base address and size of the controller's register area. + - compatible: Compatibility string. Must be 'cdns,i2c-r1p10'. + - clocks: Input clock specifier. Refer to common clock bindings. + - interrupts: Interrupt specifier. Refer to interrupt bindings. + - #address-cells: Should be 1. + - #size-cells: Should be 0. + +Optional properties: + - clock-frequency: Desired operating frequency, in Hz, of the bus. + - clock-names: Input clock name, should be 'pclk'. + +Example: + i2c@e0004000 { + compatible = "cdns,i2c-r1p10"; + clocks = <&clkc 38>; + interrupts = <GIC_SPI 25 IRQ_TYPE_LEVEL_HIGH>; + reg = <0xe0004000 0x1000>; + clock-frequency = <400000>; + #address-cells = <1>; + #size-cells = <0>; + }; diff --git a/Documentation/devicetree/bindings/i2c/i2c-designware.txt b/Documentation/devicetree/bindings/i2c/i2c-designware.txt index 7fd7fa25e9b0..5199b0c8cf7a 100644 --- a/Documentation/devicetree/bindings/i2c/i2c-designware.txt +++ b/Documentation/devicetree/bindings/i2c/i2c-designware.txt @@ -14,6 +14,12 @@ Optional properties : - i2c-sda-hold-time-ns : should contain the SDA hold time in nanoseconds. This option is only supported in hardware blocks version 1.11a or newer. + - i2c-scl-falling-time : should contain the SCL falling time in nanoseconds. + This value which is by default 300ns is used to compute the tLOW period. + + - i2c-sda-falling-time : should contain the SDA falling time in nanoseconds. + This value which is by default 300ns is used to compute the tHIGH period. + Example : i2c@f0000 { @@ -34,4 +40,6 @@ Example : interrupts = <12 1>; clock-frequency = <400000>; i2c-sda-hold-time-ns = <300>; + i2c-sda-falling-time-ns = <300>; + i2c-scl-falling-time-ns = <300>; }; diff --git a/Documentation/devicetree/bindings/i2c/i2c-efm32.txt b/Documentation/devicetree/bindings/i2c/i2c-efm32.txt new file mode 100644 index 000000000000..fc15ac519437 --- /dev/null +++ b/Documentation/devicetree/bindings/i2c/i2c-efm32.txt @@ -0,0 +1,34 @@ +* Energymicro efm32 i2c controller + +Required properties : + + - reg : Offset and length of the register set for the device + - compatible : should be "energymicro,efm32-i2c" + - interrupts : the interrupt number + - clocks : reference to the module clock + +Recommended properties : + + - clock-frequency : maximal I2C bus clock frequency in Hz. + - efm32,location : Decides the location of the USART I/O pins. + Allowed range : [0 .. 6] + +Example: + i2c0: i2c@4000a000 { + #address-cells = <1>; + #size-cells = <0>; + compatible = "energymicro,efm32-i2c"; + reg = <0x4000a000 0x400>; + interrupts = <9>; + clocks = <&cmu clk_HFPERCLKI2C0>; + clock-frequency = <100000>; + status = "ok"; + efm32,location = <3>; + + eeprom@50 { + compatible = "microchip,24c02"; + reg = <0x50>; + pagesize = <16>; + }; + }; + diff --git a/Documentation/devicetree/bindings/i2c/i2c-mv64xxx.txt b/Documentation/devicetree/bindings/i2c/i2c-mv64xxx.txt index 582b4652a82a..befd4fb4764f 100644 --- a/Documentation/devicetree/bindings/i2c/i2c-mv64xxx.txt +++ b/Documentation/devicetree/bindings/i2c/i2c-mv64xxx.txt @@ -4,12 +4,16 @@ Required properties : - reg : Offset and length of the register set for the device - - compatible : Should be "marvell,mv64xxx-i2c" or "allwinner,sun4i-i2c" - or "marvell,mv78230-i2c" or "marvell,mv78230-a0-i2c" - Note: Only use "marvell,mv78230-a0-i2c" for a very rare, - initial version of the SoC which had broken offload - support. Linux auto-detects this and sets it - appropriately. + - compatible : Should be either: + - "allwinner,sun4i-i2c" + - "allwinner,sun6i-a31-i2c" + - "marvell,mv64xxx-i2c" + - "marvell,mv78230-i2c" + - "marvell,mv78230-a0-i2c" + * Note: Only use "marvell,mv78230-a0-i2c" for a + very rare, initial version of the SoC which + had broken offload support. Linux + auto-detects this and sets it appropriately. - interrupts : The interrupt number Optional properties : @@ -17,6 +21,10 @@ Optional properties : - clock-frequency : Desired I2C bus clock frequency in Hz. If not set the default frequency is 100kHz + - resets : phandle to the parent reset controller. Mandatory + whenever you're using the "allwinner,sun6i-a31-i2c" + compatible. + Examples: i2c@11000 { diff --git a/Documentation/devicetree/bindings/i2c/i2c-rcar.txt b/Documentation/devicetree/bindings/i2c/i2c-rcar.txt index 897cfcd5ce92..dd8b2dd1edeb 100644 --- a/Documentation/devicetree/bindings/i2c/i2c-rcar.txt +++ b/Documentation/devicetree/bindings/i2c/i2c-rcar.txt @@ -6,6 +6,7 @@ Required properties: "renesas,i2c-r8a7778" "renesas,i2c-r8a7779" "renesas,i2c-r8a7790" + "renesas,i2c-r8a7791" - reg: physical base address of the controller and length of memory mapped region. - interrupts: interrupt specifier. @@ -13,11 +14,16 @@ Required properties: Optional properties: - clock-frequency: desired I2C bus clock frequency in Hz. The absence of this propoerty indicates the default frequency 100 kHz. +- clocks: clock specifier. Examples : -i2c0: i2c@e6500000 { - compatible = "renesas,i2c-rcar-h2"; - reg = <0 0xe6500000 0 0x428>; - interrupts = <0 174 0x4>; +i2c0: i2c@e6508000 { + #address-cells = <1>; + #size-cells = <0>; + compatible = "renesas,i2c-r8a7791"; + reg = <0 0xe6508000 0 0x40>; + interrupts = <0 287 IRQ_TYPE_LEVEL_HIGH>; + clocks = <&mstp9_clks R8A7791_CLK_I2C0>; + clock-frequency = <400000>; }; diff --git a/Documentation/devicetree/bindings/i2c/qcom,i2c-qup.txt b/Documentation/devicetree/bindings/i2c/qcom,i2c-qup.txt new file mode 100644 index 000000000000..dc71754a56af --- /dev/null +++ b/Documentation/devicetree/bindings/i2c/qcom,i2c-qup.txt @@ -0,0 +1,40 @@ +Qualcomm Universal Peripheral (QUP) I2C controller + +Required properties: + - compatible: Should be: + * "qcom,i2c-qup-v1.1.1" for 8660, 8960 and 8064. + * "qcom,i2c-qup-v2.1.1" for 8974 v1. + * "qcom,i2c-qup-v2.2.1" for 8974 v2 and later. + - reg: Should contain QUP register address and length. + - interrupts: Should contain I2C interrupt. + + - clocks: A list of phandles + clock-specifiers, one for each entry in + clock-names. + - clock-names: Should contain: + * "core" for the core clock + * "iface" for the AHB clock + + - #address-cells: Should be <1> Address cells for i2c device address + - #size-cells: Should be <0> as i2c addresses have no size component + +Optional properties: + - clock-frequency: Should specify the desired i2c bus clock frequency in Hz, + defaults to 100kHz if omitted. + +Child nodes should conform to i2c bus binding. + +Example: + + i2c@f9924000 { + compatible = "qcom,i2c-qup-v2.2.1"; + reg = <0xf9924000 0x1000>; + interrupts = <0 96 0>; + + clocks = <&gcc GCC_BLSP1_QUP2_I2C_APPS_CLK>, <&gcc GCC_BLSP1_AHB_CLK>; + clock-names = "core", "iface"; + + clock-frequency = <355000>; + + #address-cells = <1>; + #size-cells = <0>; + }; diff --git a/Documentation/i2c/busses/i2c-i801 b/Documentation/i2c/busses/i2c-i801 index aaaf069306a3..adf5e33e8312 100644 --- a/Documentation/i2c/busses/i2c-i801 +++ b/Documentation/i2c/busses/i2c-i801 @@ -26,6 +26,7 @@ Supported adapters: * Intel Wellsburg (PCH) * Intel Coleto Creek (PCH) * Intel Wildcat Point-LP (PCH) + * Intel BayTrail (SOC) Datasheets: Publicly available at the Intel website On Intel Patsburg and later chipsets, both the normal host SMBus controller diff --git a/Documentation/i2c/functionality b/Documentation/i2c/functionality index b0ff2ab596ce..4556a3eb87c4 100644 --- a/Documentation/i2c/functionality +++ b/Documentation/i2c/functionality @@ -46,7 +46,7 @@ A few combinations of the above flags are also defined for your convenience: and write_block_data commands I2C_FUNC_SMBUS_I2C_BLOCK Handles the SMBus read_i2c_block_data and write_i2c_block_data commands - I2C_FUNC_SMBUS_EMUL Handles all SMBus commands than can be + I2C_FUNC_SMBUS_EMUL Handles all SMBus commands that can be emulated by a real I2C adapter (using the transparent emulation layer) diff --git a/Documentation/i2c/i2c-protocol b/Documentation/i2c/i2c-protocol index 0b3e62d1f77a..ff6d6cee6c7e 100644 --- a/Documentation/i2c/i2c-protocol +++ b/Documentation/i2c/i2c-protocol @@ -6,8 +6,8 @@ Key to symbols S (1 bit) : Start bit P (1 bit) : Stop bit Rd/Wr (1 bit) : Read/Write bit. Rd equals 1, Wr equals 0. -A, NA (1 bit) : Accept and reverse accept bit. -Addr (7 bits): I2C 7 bit address. Note that this can be expanded as usual to +A, NA (1 bit) : Accept and reverse accept bit. +Addr (7 bits): I2C 7 bit address. Note that this can be expanded as usual to get a 10 bit I2C address. Comm (8 bits): Command byte, a data byte which often selects a register on the device. @@ -49,11 +49,20 @@ a byte read, followed by a byte write: Modified transactions ===================== -The following modifications to the I2C protocol can also be generated, -with the exception of I2C_M_NOSTART these are usually only needed to -work around device issues: +The following modifications to the I2C protocol can also be generated by +setting these flags for i2c messages. With the exception of I2C_M_NOSTART, they +are usually only needed to work around device issues: - Flag I2C_M_NOSTART: +I2C_M_IGNORE_NAK: + Normally message is interrupted immediately if there is [NA] from the + client. Setting this flag treats any [NA] as [A], and all of + message is sent. + These messages may still fail to SCL lo->hi timeout. + +I2C_M_NO_RD_ACK: + In a read message, master A/NA bit is skipped. + +I2C_M_NOSTART: In a combined transaction, no 'S Addr Wr/Rd [A]' is generated at some point. For example, setting I2C_M_NOSTART on the second partial message generates something like: @@ -67,17 +76,13 @@ work around device issues: I2C device but may also be used between direction changes by some rare devices. - Flags I2C_M_REV_DIR_ADDR +I2C_M_REV_DIR_ADDR: This toggles the Rd/Wr flag. That is, if you want to do a write, but need to emit an Rd instead of a Wr, or vice versa, you set this flag. For example: S Addr Rd [A] Data [A] Data [A] ... [A] Data [A] P - Flags I2C_M_IGNORE_NAK - Normally message is interrupted immediately if there is [NA] from the - client. Setting this flag treats any [NA] as [A], and all of - message is sent. - These messages may still fail to SCL lo->hi timeout. - - Flags I2C_M_NO_RD_ACK - In a read message, master A/NA bit is skipped. +I2C_M_STOP: + Force a stop condition (P) after the message. Some I2C related protocols + like SCCB require that. Normally, you really don't want to get interrupted + between the messages of one transfer. |