[U-Boot] [PATCH 05/55] dm: i2c: Add a function to transfer messages

Heiko Schocher denx hs at denx.de
Fri Jul 3 08:58:09 CEST 2015


Hello Simon,

Am 03.07.2015 um 02:15 schrieb Simon Glass:
> Sometimes it is useful to be able to transfer a raw I2C message. This
> happens when the chip address needs to be set manually, or when the data to
> be sent/received is in another buffer.
>
> Add a function to provide access to this.
>
> Signed-off-by: Simon Glass <sjg at chromium.org>
> ---
>
>   drivers/i2c/i2c-uclass.c | 11 +++++++++++
>   include/i2c.h            | 13 +++++++++++++
>   2 files changed, 24 insertions(+)

Acked-by: Heiko Schocher <hs at denx.de>

bye,
Heiko
>
> diff --git a/drivers/i2c/i2c-uclass.c b/drivers/i2c/i2c-uclass.c
> index 42d6e89..50b99ea 100644
> --- a/drivers/i2c/i2c-uclass.c
> +++ b/drivers/i2c/i2c-uclass.c
> @@ -202,6 +202,17 @@ int dm_i2c_write(struct udevice *dev, uint offset, const uint8_t *buffer,
>   	}
>   }
>
> +int dm_i2c_xfer(struct udevice *dev, struct i2c_msg *msg, int nmsgs)
> +{
> +	struct udevice *bus = dev_get_parent(dev);
> +	struct dm_i2c_ops *ops = i2c_get_ops(bus);
> +
> +	if (!ops->xfer)
> +		return -ENOSYS;
> +
> +	return ops->xfer(bus, msg, nmsgs);
> +}
> +
>   int dm_i2c_reg_read(struct udevice *dev, uint offset)
>   {
>   	uint8_t val;
> diff --git a/include/i2c.h b/include/i2c.h
> index 4c0e263..d191829 100644
> --- a/include/i2c.h
> +++ b/include/i2c.h
> @@ -191,6 +191,19 @@ int dm_i2c_reg_read(struct udevice *dev, uint offset);
>   int dm_i2c_reg_write(struct udevice *dev, uint offset, unsigned int val);
>
>   /**
> + * dm_i2c_xfer() - Transfer messages over I2C
> + *
> + * This transfers a raw message. It is best to use dm_i2c_reg_read/write()
> + * instead.
> + *
> + * @dev:	Device to use for transfer
> + * @msg:	List of messages to transfer
> + * @nmsgs:	Number of messages to transfer
> + * @return 0 on success, -ve on error
> + */
> +int dm_i2c_xfer(struct udevice *dev, struct i2c_msg *msg, int nmsgs);
> +
> +/**
>    * dm_i2c_set_bus_speed() - set the speed of a bus
>    *
>    * @bus:	Bus to adjust
>

-- 
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HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany


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