Re: [PATCH 9/9] iio: mma8452: add devicetree property to allow all pin wirings

[Jonathan Cameron <jic23@kernel.org>]

On 04/07/15 14:55, Martin Kepplinger wrote:
> For the devices supported by the mma8452 driver, two interrupt pins are
> available to route the interrupt signals to. By default INT1 is assumed.
> 
> This adds a simple boolean DT property, for users to configure it for
> INT2, if that is the wired interrupt pin for them.
> 
> This is important for everyone to be able to use this driver, no matter
> how their chip is wired.
> 
> Since this doesn't change the default behaviour, it doesn't break anything
> for existing users.
> 
> Signed-off-by: Martin Kepplinger <martin.kepplinger@theobroma-systems.com>
> Signed-off-by: Christoph Muellner <christoph.muellner@theobroma-systems.com>
I just wonder if we can make the naming more obvious.
> ---
>  Documentation/devicetree/bindings/iio/accel/mma8452.txt |  2 ++
>  drivers/iio/accel/mma8452.c                             | 14 ++++++++------
>  2 files changed, 10 insertions(+), 6 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/iio/accel/mma8452.txt b/Documentation/devicetree/bindings/iio/accel/mma8452.txt
> index 8d98e05..0048415 100644
> --- a/Documentation/devicetree/bindings/iio/accel/mma8452.txt
> +++ b/Documentation/devicetree/bindings/iio/accel/mma8452.txt
> @@ -10,6 +10,7 @@ Optional properties:
>  
>    - interrupt-parent: should be the phandle for the interrupt controller
>    - interrupts: interrupt mapping for GPIO IRQ
> +  - int2: assume interrupt pin wired to INT2 instead of INT1
use_int2 perhaps?
>  
>  Example:
>  
> @@ -18,4 +19,5 @@ Example:
>  		reg = <0x1d>;
>  		interrupt-parent = <&gpio1>;
>  		interrupts = <5 0>;
> +		int2;
>  	};
> diff --git a/drivers/iio/accel/mma8452.c b/drivers/iio/accel/mma8452.c
> index 2491ed0..0768e66 100644
> --- a/drivers/iio/accel/mma8452.c
> +++ b/drivers/iio/accel/mma8452.c
> @@ -1072,12 +1072,14 @@ static int mma8452_probe(struct i2c_client *client,
>  		int enabled_interrupts = MMA8452_INT_TRANS |
>  					 MMA8452_INT_FF_MT;
>  
> -		/* Assume wired to INT1 pin */
> -		ret = i2c_smbus_write_byte_data(client,
> -						MMA8452_CTRL_REG5,
> -						supported_interrupts);
> -		if (ret < 0)
> -			return ret;
> +		/* Assume wired to INT1 pin, except "int2" is found in DT */
> +		if (!of_property_read_bool(client->dev.of_node, "int2")) {
> +			ret = i2c_smbus_write_byte_data(client,
> +							MMA8452_CTRL_REG5,
> +							supported_interrupts);
> +			if (ret < 0)
> +				return ret;
> +		}
>  
>  		ret = i2c_smbus_write_byte_data(client,
>  						MMA8452_CTRL_REG4,
>