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author | Linus Torvalds <torvalds@linux-foundation.org> | 2015-09-09 02:16:26 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-09-09 02:16:26 +0300 |
commit | acceba598eda9817bc187f3a683a2d2ee7e7fbc7 (patch) | |
tree | 761b3950789d5eee179b75ecdafafc988ee42a46 /Documentation/devicetree/bindings/i2c/i2c.txt | |
parent | c19176154b464c861e49355eff636aa6896735b5 (diff) | |
parent | 5a73882fd2c3a86b502d54da532d373a1f2db15e (diff) | |
download | linux-acceba598eda9817bc187f3a683a2d2ee7e7fbc7.tar.xz |
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/devicetree/bindings/i2c/i2c.txt')
-rw-r--r-- | Documentation/devicetree/bindings/i2c/i2c.txt | 45 |
1 files changed, 45 insertions, 0 deletions
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. |