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| author | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2017-01-04 20:57:22 -0800 |
|---|---|---|
| committer | Wolfram Sang <wsa@the-dreams.de> | 2017-01-12 20:06:15 +0100 |
| commit | 331c34255293cd02d395b7097008b509ba89e60e (patch) | |
| tree | 90c079b378ecb58eaa9dac6341ae9c776bc97019 /Documentation | |
| parent | 30f939feaeee23e21391cfc7b484f012eb189c3c (diff) | |
| download | linux-331c34255293cd02d395b7097008b509ba89e60e.tar.gz linux-331c34255293cd02d395b7097008b509ba89e60e.tar.bz2 linux-331c34255293cd02d395b7097008b509ba89e60e.zip | |
i2c: do not enable fall back to Host Notify by default
Falling back unconditionally to HostNotify as primary client's interrupt
breaks some drivers which alter their functionality depending on whether
interrupt is present or not, so let's introduce a board flag telling I2C
core explicitly if we want wired interrupt or HostNotify-based one:
I2C_CLIENT_HOST_NOTIFY.
For DT-based systems we introduce "host-notify" property that we convert
to I2C_CLIENT_HOST_NOTIFY board flag.
Tested-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Pali Rohár <pali.rohar@gmail.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/devicetree/bindings/i2c/i2c.txt | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/i2c/i2c.txt b/Documentation/devicetree/bindings/i2c/i2c.txt index 5fa691e6f638..cee9d5055fa2 100644 --- a/Documentation/devicetree/bindings/i2c/i2c.txt +++ b/Documentation/devicetree/bindings/i2c/i2c.txt @@ -62,6 +62,9 @@ wants to support one of the below features, it should adapt the bindings below. "irq" and "wakeup" names are recognized by I2C core, other names are left to individual drivers. +- host-notify + device uses SMBus host notify protocol instead of interrupt line. + - multi-master states that there is another master active on this bus. The OS can use this information to adapt power management to keep the arbitration awake @@ -81,6 +84,11 @@ 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. +Alternatively, devices supporting SMbus Host Notify, and connected to +adapters that support this feature, may use "host-notify" property. I2C +core will create a virtual interrupt for Host Notify and assign it 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. |