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author | Linus Torvalds <torvalds@linux-foundation.org> | 2015-09-08 16:16:26 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-09-08 16:16:26 -0700 |
commit | acceba598eda9817bc187f3a683a2d2ee7e7fbc7 (patch) | |
tree | 761b3950789d5eee179b75ecdafafc988ee42a46 /Documentation | |
parent | c19176154b464c861e49355eff636aa6896735b5 (diff) | |
parent | 5a73882fd2c3a86b502d54da532d373a1f2db15e (diff) | |
download | lwn-acceba598eda9817bc187f3a683a2d2ee7e7fbc7.tar.gz lwn-acceba598eda9817bc187f3a683a2d2ee7e7fbc7.zip |
Merge branch 'i2c/for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:
"Features:
- new drivers: Renesas EMEV2, register based MUX, NXP LPC2xxx
- core: scans DT and assigns wakeup interrupts. no driver changes needed.
- core: some refcouting issues fixed and better API for that
- core: new helper function for best effort block read emulation
- slave framework: proper DT bindings and userspace instantiation
- some bigger work for xiic, pxa, omap drivers
.. and quite a number of smaller driver fixes, cleanups, improvements"
* 'i2c/for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (65 commits)
i2c: mux: reg Change ioread endianness for readback
i2c: mux: reg: fix compilation warnings
i2c: mux: reg: simplify register size checking
i2c: muxes: fix leaked i2c adapter device node references
i2c: allow specifying separate wakeup interrupt in device tree
of/irq: export of_get_irq_byname()
i2c: xgene-slimpro: dma_mapping_error() doesn't return an error code
i2c: Replace I2C_CROS_EC_TUNNEL dependency
eeprom: at24: use i2c_smbus_read_i2c_block_data_or_emulated
i2c: core: Add support for best effort block read emulation
i2c: lpc2k: add driver
i2c: mux: Add register-based mux i2c-mux-reg
i2c: dt: describe generic bindings
i2c: slave: print warning if slave flag not set
i2c: support 10 bit and slave addresses in sysfs 'new_device'
i2c: take address space into account when checking for used addresses
i2c: apply DT flags when probing
i2c: make address check indpendent from client struct
i2c: rename address check functions
i2c: apply address offset for slaves, too
...
Diffstat (limited to 'Documentation')
13 files changed, 192 insertions, 4 deletions
diff --git a/Documentation/devicetree/bindings/i2c/ina209.txt b/Documentation/devicetree/bindings/hwmon/ina209.txt index 9dd2bee80840..9dd2bee80840 100644 --- a/Documentation/devicetree/bindings/i2c/ina209.txt +++ b/Documentation/devicetree/bindings/hwmon/ina209.txt diff --git a/Documentation/devicetree/bindings/i2c/ina2xx.txt b/Documentation/devicetree/bindings/hwmon/ina2xx.txt index a2ad85d7e747..a2ad85d7e747 100644 --- a/Documentation/devicetree/bindings/i2c/ina2xx.txt +++ b/Documentation/devicetree/bindings/hwmon/ina2xx.txt diff --git a/Documentation/devicetree/bindings/i2c/max6697.txt b/Documentation/devicetree/bindings/hwmon/max6697.txt index 5f793998e4a4..5f793998e4a4 100644 --- a/Documentation/devicetree/bindings/i2c/max6697.txt +++ b/Documentation/devicetree/bindings/hwmon/max6697.txt diff --git a/Documentation/devicetree/bindings/i2c/i2c-cadence.txt b/Documentation/devicetree/bindings/i2c/i2c-cadence.txt index 7cb0b5608f49..ebaa90c58c8e 100644 --- a/Documentation/devicetree/bindings/i2c/i2c-cadence.txt +++ b/Documentation/devicetree/bindings/i2c/i2c-cadence.txt @@ -2,7 +2,11 @@ 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'. + - compatible: Should contain one of: + * "cdns,i2c-r1p10" + Note: Use this when cadence i2c controller version 1.0 is used. + * "cdns,i2c-r1p14" + Note: Use this when cadence i2c controller version 1.4 is used. - clocks: Input clock specifier. Refer to common clock bindings. - interrupts: Interrupt specifier. Refer to interrupt bindings. - #address-cells: Should be 1. diff --git a/Documentation/devicetree/bindings/i2c/i2c-emev2.txt b/Documentation/devicetree/bindings/i2c/i2c-emev2.txt new file mode 100644 index 000000000000..5ed1ea1c7e14 --- /dev/null +++ b/Documentation/devicetree/bindings/i2c/i2c-emev2.txt @@ -0,0 +1,22 @@ +Device tree configuration for Renesas EMEV2 IIC controller + +Required properties: +- compatible : "renesas,iic-emev2" +- reg : address start and address range size of device +- interrupts : specifier for the IIC controller interrupt +- clocks : phandle to the IP core SCLK +- clock-names : must be "sclk" +- #address-cells : should be <1> +- #size-cells : should be <0> + +Example: + + iic0: i2c@e0070000 { + #address-cells = <1>; + #size-cells = <0>; + compatible = "renesas,iic-emev2"; + reg = <0xe0070000 0x28>; + interrupts = <0 32 IRQ_TYPE_EDGE_RISING>; + clocks = <&iic0_sclk>; + clock-names = "sclk"; + }; diff --git a/Documentation/devicetree/bindings/i2c/i2c-lpc2k.txt b/Documentation/devicetree/bindings/i2c/i2c-lpc2k.txt new file mode 100644 index 000000000000..4101aa621ad4 --- /dev/null +++ b/Documentation/devicetree/bindings/i2c/i2c-lpc2k.txt @@ -0,0 +1,33 @@ +NXP I2C controller for LPC2xxx/178x/18xx/43xx + +Required properties: + - compatible: must be "nxp,lpc1788-i2c" + - reg: physical address and length of the device registers + - interrupts: a single interrupt specifier + - clocks: clock for the device + - #address-cells: should be <1> + - #size-cells: should be <0> + +Optional properties: +- clock-frequency: the desired I2C bus clock frequency in Hz; in + absence of this property the default value is used (100 kHz). + +Example: +i2c0: i2c@400a1000 { + compatible = "nxp,lpc1788-i2c"; + reg = <0x400a1000 0x1000>; + interrupts = <18>; + clocks = <&ccu1 CLK_APB1_I2C0>; + #address-cells = <1>; + #size-cells = <0>; +}; + +&i2c0 { + clock-frequency = <400000>; + + lm75@48 { + compatible = "nxp,lm75"; + reg = <0x48>; + }; +}; + diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-reg.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-reg.txt new file mode 100644 index 000000000000..688783fbe696 --- /dev/null +++ b/Documentation/devicetree/bindings/i2c/i2c-mux-reg.txt @@ -0,0 +1,74 @@ +Register-based I2C Bus Mux + +This binding describes an I2C bus multiplexer that uses a single register +to route the I2C signals. + +Required properties: +- compatible: i2c-mux-reg +- i2c-parent: The phandle of the I2C bus that this multiplexer's master-side + port is connected to. +* Standard I2C mux properties. See mux.txt in this directory. +* I2C child bus nodes. See mux.txt in this directory. + +Optional properties: +- reg: this pair of <offset size> specifies the register to control the mux. + The <offset size> depends on its parent node. It can be any memory-mapped + address. The size must be either 1, 2, or 4 bytes. If reg is omitted, the + resource of this device will be used. +- little-endian: The existence indicates the register is in little endian. +- big-endian: The existence indicates the register is in big endian. + If both little-endian and big-endian are omitted, the endianness of the + CPU will be used. +- write-only: The existence indicates the register is write-only. +- idle-state: value to set the muxer to when idle. When no value is + given, it defaults to the last value used. + +Whenever an access is made to a device on a child bus, the value set +in the revelant node's reg property will be output to the register. + +If an idle state is defined, using the idle-state (optional) property, +whenever an access is not being made to a device on a child bus, the +register will be set according to the idle value. + +If an idle state is not defined, the most recently used value will be +left programmed into the register. + +Example of a mux on PCIe card, the host is a powerpc SoC (big endian): + + i2c-mux { + /* the <offset size> depends on the address translation + * of the parent device. If omitted, device resource + * will be used instead. The size is to determine + * whether iowrite32, iowrite16, or iowrite8 will be used. + */ + reg = <0x6028 0x4>; + little-endian; /* little endian register on PCIe */ + compatible = "i2c-mux-reg"; + #address-cells = <1>; + #size-cells = <0>; + i2c-parent = <&i2c1>; + i2c@0 { + reg = <0>; + #address-cells = <1>; + #size-cells = <0>; + + si5338: clock-generator@70 { + compatible = "silabs,si5338"; + reg = <0x70>; + /* other stuff */ + }; + }; + + i2c@1 { + /* data is written using iowrite32 */ + reg = <1>; + #address-cells = <1>; + #size-cells = <0>; + + si5338: clock-generator@70 { + compatible = "silabs,si5338"; + reg = <0x70>; + /* other stuff */ + }; + }; + }; diff --git a/Documentation/devicetree/bindings/i2c/i2c.txt b/Documentation/devicetree/bindings/i2c/i2c.txt new file mode 100644 index 000000000000..8a99150ac3a7 --- /dev/null +++ b/Documentation/devicetree/bindings/i2c/i2c.txt @@ -0,0 +1,45 @@ +Generic device tree bindings for I2C busses +=========================================== + +This document describes generic bindings which can be used to describe I2C +busses in a device tree. + +Required properties +------------------- + +- #address-cells - should be <1>. Read more about addresses below. +- #size-cells - should be <0>. +- compatible - name of I2C bus controller following generic names + recommended practice. + +For other required properties e.g. to describe register sets, +clocks, etc. check the binding documentation of the specific driver. + +The cells properties above define that an address of children of an I2C bus +are described by a single value. This is usually a 7 bit address. However, +flags can be attached to the address. I2C_TEN_BIT_ADDRESS is used to mark a 10 +bit address. It is needed to avoid the ambiguity between e.g. a 7 bit address +of 0x50 and a 10 bit address of 0x050 which, in theory, can be on the same bus. +Another flag is I2C_OWN_SLAVE_ADDRESS to mark addresses on which we listen to +be devices ourselves. + +Optional properties +------------------- + +These properties may not be supported by all drivers. However, if a driver +wants to support one of the below features, it should adapt the bindings below. + +- clock-frequency - frequency of bus clock in Hz. +- wakeup-source - device can be used as a wakeup source. + +- interrupts - interrupts used by the device. +- interrupt-names - "irq" and "wakeup" names are recognized by I2C core, + other names are left to individual drivers. + +Binding may contain optional "interrupts" property, describing interrupts +used by the device. I2C core will assign "irq" interrupt (or the very first +interrupt if not using interrupt names) as primary interrupt for the slave. + +Also, if device is marked as a wakeup source, I2C core will set up "wakeup" +interrupt for the device. If "wakeup" interrupt name is not present in the +binding, then primary interrupt will be used as wakeup interrupt. diff --git a/Documentation/devicetree/bindings/i2c/trivial-devices.txt b/Documentation/devicetree/bindings/i2c/trivial-devices.txt index 00f8652e193a..d77d412cbc68 100644 --- a/Documentation/devicetree/bindings/i2c/trivial-devices.txt +++ b/Documentation/devicetree/bindings/i2c/trivial-devices.txt @@ -95,6 +95,8 @@ stm,m41t00 Serial Access TIMEKEEPER stm,m41t62 Serial real-time clock (RTC) with alarm stm,m41t80 M41T80 - SERIAL ACCESS RTC WITH ALARMS taos,tsl2550 Ambient Light Sensor with SMBUS/Two Wire Serial Interface +ti,ads7828 8-Channels, 12-bit ADC +ti,ads7830 8-Channels, 8-bit ADC ti,tsc2003 I2C Touch-Screen Controller ti,tmp102 Low Power Digital Temperature Sensor with SMBUS/Two Wire Serial Interface ti,tmp103 Low Power Digital Temperature Sensor with SMBUS/Two Wire Serial Interface diff --git a/Documentation/devicetree/bindings/i2c/ti,bq32k.txt b/Documentation/devicetree/bindings/rtc/ti,bq32k.txt index e204906b9ad3..e204906b9ad3 100644 --- a/Documentation/devicetree/bindings/i2c/ti,bq32k.txt +++ b/Documentation/devicetree/bindings/rtc/ti,bq32k.txt diff --git a/Documentation/i2c/busses/i2c-parport b/Documentation/i2c/busses/i2c-parport index 0e2d17b460fd..c3dbb3bfd814 100644 --- a/Documentation/i2c/busses/i2c-parport +++ b/Documentation/i2c/busses/i2c-parport @@ -20,6 +20,7 @@ It currently supports the following devices: * (type=5) Analog Devices evaluation boards: ADM1025, ADM1030, ADM1031 * (type=6) Barco LPT->DVI (K5800236) adapter * (type=7) One For All JP1 parallel port adapter + * (type=8) VCT-jig These devices use different pinout configurations, so you have to tell the driver what you have, using the type module parameter. There is no diff --git a/Documentation/i2c/slave-interface b/Documentation/i2c/slave-interface index 2dee4e2d62df..61ed05cd9531 100644 --- a/Documentation/i2c/slave-interface +++ b/Documentation/i2c/slave-interface @@ -31,10 +31,13 @@ User manual =========== I2C slave backends behave like standard I2C clients. So, you can instantiate -them as described in the document 'instantiating-devices'. A quick example for -instantiating the slave-eeprom driver from userspace at address 0x64 on bus 1: +them as described in the document 'instantiating-devices'. The only difference +is that i2c slave backends have their own address space. So, you have to add +0x1000 to the address you would originally request. An example for +instantiating the slave-eeprom driver from userspace at the 7 bit address 0x64 +on bus 1: - # echo slave-24c02 0x64 > /sys/bus/i2c/devices/i2c-1/new_device + # echo slave-24c02 0x1064 > /sys/bus/i2c/devices/i2c-1/new_device Each backend should come with separate documentation to describe its specific behaviour and setup. diff --git a/Documentation/i2c/ten-bit-addresses b/Documentation/i2c/ten-bit-addresses index cdfe13901b99..7b2d11e53a49 100644 --- a/Documentation/i2c/ten-bit-addresses +++ b/Documentation/i2c/ten-bit-addresses @@ -2,6 +2,10 @@ The I2C protocol knows about two kinds of device addresses: normal 7 bit addresses, and an extended set of 10 bit addresses. The sets of addresses do not intersect: the 7 bit address 0x10 is not the same as the 10 bit address 0x10 (though a single device could respond to both of them). +To avoid ambiguity, the user sees 10 bit addresses mapped to a different +address space, namely 0xa000-0xa3ff. The leading 0xa (= 10) represents the +10 bit mode. This is used for creating device names in sysfs. It is also +needed when instantiating 10 bit devices via the new_device file in sysfs. I2C messages to and from 10-bit address devices have a different format. See the I2C specification for the details. |