Commit Graph

4 Commits

Author SHA1 Message Date
Wolfram Sang
0c739738a0 i2c: document binding for multi-master case
We need this binding because some I2C master drivers will need to adapt
their PM settings for the arbitration circuitry.

Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-01-02 22:10:32 +01:00
Wolfram Sang
99b809d7bd i2c: document generic DT bindings for timing parameters
Also, sort the properties alphabetically and make indentation
consistent. Wording largely taken from i2c-rk3x.txt, thanks guys!

Only "i2c-scl-internal-delay-ns" is new, the rest is used by two drivers
already and was documented in their driver binding documentation.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-12-14 10:39:01 +01:00
Dmitry Torokhov
3fffd12839 i2c: allow specifying separate wakeup interrupt in device tree
Instead of having each i2c driver individually parse device tree data in
case it or platform supports separate wakeup interrupt, and handle
enabling and disabling wakeup interrupts in their power management
routines, let's have i2c core do that for us.

Platforms wishing to specify separate wakeup interrupt for the device
should use named interrupt syntax in their DTSes:

	interrupt-parent = <&intc1>;
	interrupts = <5 0>, <6 0>;
	interrupt-names = "irq", "wakeup";

This patch is inspired by work done by Vignesh R <vigneshr@ti.com> for
pixcir_i2c_ts driver.

Note that the original code tried to preserve any existing wakeup
settings from userspace but was not quite right in that regard:
it would preserve wakeup flag set by userspace upon driver rebinding;
but it would re-arm the wakeup flag if it was disabled by userspace.

We think that resetting the flag upon re-binding the driver is proper
behavior as the driver is responsible for setting up and handling
wakeups.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Tested-by: Vignesh R <vigneshr@ti.com>
[wsa: updated the commit message]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-08-26 18:47:58 +02:00
Wolfram Sang
7a59b00a09 i2c: dt: describe generic bindings
Start a new file which describes the generic bindings used for I2C with
device tree. So we have a central place to look for them, increase
visibility of them, and hopefully reduce the amount of custom properties
introduced.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Vaibhav Hiremath <vaibhav.hiremath@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-08-24 14:05:17 +02:00